{
    "mode": "man",
    "parameter": "cc",
    "section": "1",
    "url": "https://www.chedong.com/phpMan.php/man/cc/1/json",
    "generated": "2026-08-12T03:01:38Z",
    "synopsis": "gcc [-c|-S|-E] [-std=standard]\n[-g] [-pg] [-Olevel]\n[-Wwarn...] [-Wpedantic]\n[-Idir...] [-Ldir...]\n[-Dmacro[=defn]...] [-Umacro]\n[-foption...] [-mmachine-option...]\n[-o outfile] [@file] infile...\nOnly the most useful options are listed here; see below for the remainder.  g++ accepts\nmostly the same options as gcc.",
    "sections": {
        "NAME": {
            "content": "gcc - GNU project C and C++ compiler\n",
            "subsections": []
        },
        "SYNOPSIS": {
            "content": "gcc [-c|-S|-E] [-std=standard]\n[-g] [-pg] [-Olevel]\n[-Wwarn...] [-Wpedantic]\n[-Idir...] [-Ldir...]\n[-Dmacro[=defn]...] [-Umacro]\n[-foption...] [-mmachine-option...]\n[-o outfile] [@file] infile...\n\nOnly the most useful options are listed here; see below for the remainder.  g++ accepts\nmostly the same options as gcc.\n",
            "subsections": []
        },
        "DESCRIPTION": {
            "content": "When you invoke GCC, it normally does preprocessing, compilation, assembly and linking.  The\n\"overall options\" allow you to stop this process at an intermediate stage.  For example, the",
            "subsections": [
                {
                    "name": "-c",
                    "content": "assembler.\n\nOther options are passed on to one or more stages of processing.  Some options control the\npreprocessor and others the compiler itself.  Yet other options control the assembler and\nlinker; most of these are not documented here, since you rarely need to use any of them.\n\nMost of the command-line options that you can use with GCC are useful for C programs; when an\noption is only useful with another language (usually C++), the explanation says so\nexplicitly.  If the description for a particular option does not mention a source language,\nyou can use that option with all supported languages.\n\nThe usual way to run GCC is to run the executable called gcc, or machine-gcc when cross-\ncompiling, or machine-gcc-version to run a specific version of GCC.  When you compile C++\nprograms, you should invoke GCC as g++ instead.\n\nThe gcc program accepts options and file names as operands.  Many options have multi-letter\nnames; therefore multiple single-letter options may not be grouped: -dv is very different\nfrom -d -v.\n\nYou can mix options and other arguments.  For the most part, the order you use doesn't\nmatter.  Order does matter when you use several options of the same kind; for example, if you\nspecify -L more than once, the directories are searched in the order specified.  Also, the\nplacement of the -l option is significant.\n\nMany options have long names starting with -f or with -W---for example,",
                    "flag": "-c"
                },
                {
                    "name": "-fmove-loop-invariants -Wformat",
                    "content": "forms; the negative form of -ffoo is -fno-foo.  This manual documents only one of these two\nforms, whichever one is not the default.\n\nSome options take one or more arguments typically separated either by a space or by the\nequals sign (=) from the option name.  Unless documented otherwise, an argument can be either\nnumeric or a string.  Numeric arguments must typically be small unsigned decimal or\nhexadecimal integers.  Hexadecimal arguments must begin with the 0x prefix.  Arguments to\noptions that specify a size threshold of some sort may be arbitrarily large decimal or\nhexadecimal integers followed by a byte size suffix designating a multiple of bytes such as\n\"kB\" and \"KiB\" for kilobyte and kibibyte, respectively, \"MB\" and \"MiB\" for megabyte and\nmebibyte, \"GB\" and \"GiB\" for gigabyte and gigibyte, and so on.  Such arguments are designated\nby byte-size in the following text.  Refer to the NIST, IEC, and other relevant national and\ninternational standards for the full listing and explanation of the binary and decimal byte\nsize prefixes.\n"
                }
            ]
        },
        "OPTIONS": {
            "content": "",
            "subsections": [
                {
                    "name": "Option Summary",
                    "content": "Here is a summary of all the options, grouped by type.  Explanations are in the following\nsections.\n\nOverall Options\n-c   -S   -E   -o  file -dumpbase dumpbase  -dumpbase-ext auxdropsuf -dumpdir dumppfx  -x\nlanguage -v  -###  --help[=class[,...]]  --target-help  --version -pass-exit-codes  -pipe\n-specs=file  -wrapper @file  -ffile-prefix-map=old=new  -fcanon-prefix-map  -fplugin=file\n-fplugin-arg-name=arg -fdump-ada-spec[-slim]  -fada-spec-parent=unit  -fdump-go-spec=file\n\nC Language Options\n-ansi   -std=standard   -aux-info  filename  -fno-asm -fno-builtin  -fno-builtin-function\n-fcond-mismatch   -ffreestanding    -fgimple     -fgnu-tm     -fgnu89-inline     -fhosted\n-flax-vector-conversions   -fms-extensions -foffload=arg  -foffload-options=arg -fopenacc\n-fopenacc-dim=geom  -fopenmp    -fopenmp-simd    -fopenmp-target-simd-clone[=device-type]\n-fpermitted-flt-eval-methods=standard        -fplan9-extensions        -fsigned-bitfields\n-funsigned-bitfields     -fsigned-char      -funsigned-char      -fstrict-flex-arrays[=n]\n-fsso-struct=endianness\n\nC++ Language Options\n-fabi-version=n    -fno-access-control   -faligned-new=n    -fargs-in-order=n   -fchar8t\n-fcheck-new   -fconstexpr-depth=n    -fconstexpr-cache-depth=n   -fconstexpr-loop-limit=n\n-fconstexpr-ops-limit=n  -fno-elide-constructors  -fno-enforce-eh-specs -fno-gnu-keywords\n-fno-implicit-templates       -fno-implicit-inline-templates       -fno-implement-inlines\n-fmodule-header[=kind]      -fmodule-only      -fmodules-ts      -fmodule-implicit-inline\n-fno-module-lazy  -fmodule-mapper=specification  -fmodule-version-ignore  -fms-extensions\n-fnew-inheriting-ctors     -fnew-ttp-matching     -fno-nonansi-builtins     -fnothrow-opt\n-fno-operator-names  -fno-optional-diags   -fpermissive  -fno-pretty-templates  -fno-rtti\n-fsized-deallocation            -ftemplate-backtrace-limit=n           -ftemplate-depth=n\n-fno-threadsafe-statics          -fuse-cxa-atexit         -fno-weak           -nostdinc++\n-fvisibility-inlines-hidden         -fvisibility-ms-compat         -fext-numeric-literals\n-flang-info-include-translate[=header]                  -flang-info-include-translate-not\n-flang-info-module-cmi[=module]    -stdlib=libstdc++,libc++    -Wabi-tag    -Wcatch-value\n-Wcatch-value=n      -Wno-class-conversion       -Wclass-memaccess      -Wcomma-subscript\n-Wconditionally-supported          -Wno-conversion-null          -Wctad-maybe-unsupported\n-Wctor-dtor-privacy              -Wdangling-reference              -Wno-delete-incomplete\n-Wdelete-non-virtual-dtor          -Wno-deprecated-array-compare        -Wdeprecated-copy\n-Wdeprecated-copy-dtor                               -Wno-deprecated-enum-enum-conversion\n-Wno-deprecated-enum-float-conversion      -Weffc++      -Wno-exceptions     -Wextra-semi\n-Wno-inaccessible-base       -Wno-inherited-variadic-ctor         -Wno-init-list-lifetime\n-Winvalid-constexpr  -Winvalid-imported-macros -Wno-invalid-offsetof  -Wno-literal-suffix\n-Wmismatched-new-delete    -Wmismatched-tags     -Wmultiple-inheritance      -Wnamespaces\n-Wnarrowing    -Wnoexcept     -Wnoexcept-type     -Wnon-virtual-dtor   -Wpessimizing-move\n-Wno-placement-new      -Wplacement-new=n     -Wrange-loop-construct     -Wredundant-move\n-Wredundant-tags  -Wreorder   -Wregister  -Wstrict-null-sentinel   -Wno-subobject-linkage\n-Wtemplates     -Wno-non-template-friend       -Wold-style-cast      -Woverloaded-virtual\n-Wno-pmf-conversions         -Wself-move         -Wsign-promo        -Wsized-deallocation\n-Wsuggest-final-methods    -Wsuggest-final-types     -Wsuggest-override    -Wno-terminate\n-Wuseless-cast     -Wno-vexing-parse    -Wvirtual-inheritance    -Wno-virtual-move-assign\n-Wvolatile  -Wzero-as-null-pointer-constant\n\nObjective-C and Objective-C++ Language Options\n-fconstant-string-class=class-name   -fgnu-runtime    -fnext-runtime   -fno-nil-receivers\n-fobjc-abi-version=n   -fobjc-call-cxx-cdtors   -fobjc-direct-dispatch  -fobjc-exceptions\n-fobjc-gc           -fobjc-nilcheck           -fobjc-std=objc1           -fno-local-ivars\n-fivar-visibility=[public|protected|private|package]  -freplace-objc-classes  -fzero-link\n-gen-decls      -Wassign-intercept       -Wno-property-assign-default       -Wno-protocol\n-Wobjc-root-class -Wselector -Wstrict-selector-match -Wundeclared-selector\n\nDiagnostic Message Formatting Options\n-fmessage-length=n   -fdiagnostics-plain-output  -fdiagnostics-show-location=[once|every-\nline]   -fdiagnostics-color=[auto|never|always]    -fdiagnostics-urls=[auto|never|always]\n-fdiagnostics-format=[text|sarif-stderr|sarif-file|json|json-stderr|json-file]\n-fno-diagnostics-show-option    -fno-diagnostics-show-caret  -fno-diagnostics-show-labels\n-fno-diagnostics-show-line-numbers  -fno-diagnostics-show-cwe  -fno-diagnostics-show-rule\n-fdiagnostics-minimum-margin-width=width                   -fdiagnostics-parseable-fixits\n-fdiagnostics-generate-patch      -fdiagnostics-show-template-tree        -fno-elide-type\n-fdiagnostics-path-format=[none|separate-events|inline-events]\n-fdiagnostics-show-path-depths  -fno-show-column -fdiagnostics-column-unit=[display|byte]\n-fdiagnostics-column-origin=origin -fdiagnostics-escape-format=[unicode|bytes]\n\nWarning Options\n-fsyntax-only  -fmax-errors=n  -Wpedantic -pedantic-errors -w   -Wextra   -Wall   -Wabi=n\n-Waddress                 -Wno-address-of-packed-member                -Waggregate-return\n-Walloc-size-larger-than=byte-size  -Walloc-zero -Walloca  -Walloca-larger-than=byte-size\n-Wno-aggressive-loop-optimizations  -Warith-conversion  -Warray-bounds   -Warray-bounds=n\n-Warray-compare       -Wno-attributes       -Wattribute-alias=n      -Wno-attribute-alias\n-Wno-attribute-warning        -Wbidi-chars=[none|unpaired|any|ucn]         -Wbool-compare\n-Wbool-operation      -Wno-builtin-declaration-mismatch      -Wno-builtin-macro-redefined\n-Wc90-c99-compat    -Wc99-c11-compat   -Wc11-c2x-compat   -Wc++-compat     -Wc++11-compat\n-Wc++14-compat          -Wc++17-compat        -Wc++20-compat        -Wno-c++11-extensions\n-Wno-c++14-extensions -Wno-c++17-extensions -Wno-c++20-extensions   -Wno-c++23-extensions\n-Wcast-align   -Wcast-align=strict   -Wcast-function-type   -Wcast-qual -Wchar-subscripts\n-Wclobbered   -Wcomment  -Wno-complain-wrong-lang  -Wconversion    -Wno-coverage-mismatch\n-Wno-cpp    -Wdangling-else     -Wdangling-pointer     -Wdangling-pointer=n   -Wdate-time\n-Wno-deprecated             -Wno-deprecated-declarations             -Wno-designated-init\n-Wdisabled-optimization     -Wno-discarded-array-qualifiers     -Wno-discarded-qualifiers\n-Wno-div-by-zero      -Wdouble-promotion     -Wduplicated-branches      -Wduplicated-cond\n-Wempty-body   -Wno-endif-labels   -Wenum-compare   -Wenum-conversion -Wenum-int-mismatch\n-Werror     -Werror=*     -Wexpansion-to-defined     -Wfatal-errors    -Wfloat-conversion\n-Wfloat-equal    -Wformat   -Wformat=2  -Wno-format-contains-nul   -Wno-format-extra-args\n-Wformat-nonliteral     -Wformat-overflow=n    -Wformat-security      -Wformat-signedness\n-Wformat-truncation=n    -Wformat-y2k     -Wframe-address   -Wframe-larger-than=byte-size\n-Wno-free-nonheap-object           -Wno-if-not-aligned            -Wno-ignored-attributes\n-Wignored-qualifiers   -Wno-incompatible-pointer-types -Wimplicit  -Wimplicit-fallthrough\n-Wimplicit-fallthrough=n      -Wno-implicit-function-declaration        -Wno-implicit-int\n-Winfinite-recursion  -Winit-self   -Winline   -Wno-int-conversion  -Wint-in-bool-context\n-Wno-int-to-pointer-cast    -Wno-invalid-memory-model    -Winvalid-pch     -Winvalid-utf8\n-Wno-unicode    -Wjump-misses-init   -Wlarger-than=byte-size    -Wlogical-not-parentheses\n-Wlogical-op   -Wlong-long     -Wno-lto-type-mismatch    -Wmain     -Wmaybe-uninitialized\n-Wmemset-elt-size             -Wmemset-transposed-args           -Wmisleading-indentation\n-Wmissing-attributes             -Wmissing-braces            -Wmissing-field-initializers\n-Wmissing-format-attribute           -Wmissing-include-dirs            -Wmissing-noreturn\n-Wno-missing-profile       -Wno-multichar        -Wmultistatement-macros        -Wnonnull\n-Wnonnull-compare     -Wnormalized=[none|id|nfc|nfkc]     -Wnull-dereference     -Wno-odr\n-Wopenacc-parallelism       -Wopenmp-simd       -Wno-overflow        -Woverlength-strings\n-Wno-override-init-side-effects           -Wpacked            -Wno-packed-bitfield-compat\n-Wpacked-not-aligned   -Wpadded  -Wparentheses   -Wno-pedantic-ms-format  -Wpointer-arith\n-Wno-pointer-compare     -Wno-pointer-to-int-cast    -Wno-pragmas     -Wno-prio-ctor-dtor\n-Wredundant-decls        -Wrestrict         -Wno-return-local-addr          -Wreturn-type\n-Wno-scalar-storage-order   -Wsequence-point  -Wshadow   -Wshadow=global   -Wshadow=local\n-Wshadow=compatible-local           -Wno-shadow-ivar            -Wno-shift-count-negative\n-Wno-shift-count-overflow  -Wshift-negative-value -Wno-shift-overflow  -Wshift-overflow=n\n-Wsign-compare      -Wsign-conversion    -Wno-sizeof-array-argument    -Wsizeof-array-div\n-Wsizeof-pointer-div  -Wsizeof-pointer-memaccess  -Wstack-protector   -Wstack-usage=byte-\nsize    -Wstrict-aliasing   -Wstrict-aliasing=n   -Wstrict-overflow   -Wstrict-overflow=n\n-Wstring-compare -Wno-stringop-overflow  -Wno-stringop-overread  -Wno-stringop-truncation\n-Wstrict-flex-arrays   -Wsuggest-attribute=[pure|const|noreturn|format|malloc]   -Wswitch\n-Wno-switch-bool      -Wswitch-default       -Wswitch-enum      -Wno-switch-outside-range\n-Wno-switch-unreachable      -Wsync-nand     -Wsystem-headers      -Wtautological-compare\n-Wtrampolines   -Wtrigraphs   -Wtrivial-auto-var-init   -Wtsan   -Wtype-limits    -Wundef\n-Wuninitialized        -Wunknown-pragmas      -Wunsuffixed-float-constants       -Wunused\n-Wunused-but-set-parameter        -Wunused-but-set-variable       -Wunused-const-variable\n-Wunused-const-variable=n   -Wunused-function    -Wunused-label   -Wunused-local-typedefs\n-Wunused-macros -Wunused-parameter  -Wno-unused-result -Wunused-value   -Wunused-variable\n-Wno-varargs         -Wvariadic-macros        -Wvector-operation-performance        -Wvla\n-Wvla-larger-than=byte-size          -Wno-vla-larger-than         -Wvolatile-register-var\n-Wwrite-strings -Wxor-used-as-pow -Wzero-length-bounds\n\nStatic Analyzer Options\n-fanalyzer  -fanalyzer-call-summaries  -fanalyzer-checker=name  -fno-analyzer-feasibility\n-fanalyzer-fine-grained        -fno-analyzer-state-merge        -fno-analyzer-state-purge\n-fno-analyzer-suppress-followups    -fanalyzer-transitivity   -fno-analyzer-undo-inlining\n-fanalyzer-verbose-edges   -fanalyzer-verbose-state-changes    -fanalyzer-verbosity=level\n-fdump-analyzer          -fdump-analyzer-callgraph         -fdump-analyzer-exploded-graph\n-fdump-analyzer-exploded-nodes                           -fdump-analyzer-exploded-nodes-2\n-fdump-analyzer-exploded-nodes-3                           -fdump-analyzer-exploded-paths\n-fdump-analyzer-feasibility       -fdump-analyzer-json        -fdump-analyzer-state-purge\n-fdump-analyzer-stderr        -fdump-analyzer-supergraph        -fdump-analyzer-untracked\n-Wno-analyzer-double-fclose                                     -Wno-analyzer-double-free\n-Wno-analyzer-exposure-through-output-file     -Wno-analyzer-exposure-through-uninit-copy\n-Wno-analyzer-fd-access-mode-mismatch -Wno-analyzer-fd-double-close -Wno-analyzer-fd-leak\n-Wno-analyzer-fd-phase-mismatch                            -Wno-analyzer-fd-type-mismatch\n-Wno-analyzer-fd-use-after-close                       -Wno-analyzer-fd-use-without-check\n-Wno-analyzer-file-leak                                    -Wno-analyzer-free-of-non-heap\n-Wno-analyzer-imprecise-fp-arithmetic                    -Wno-analyzer-infinite-recursion\n-Wno-analyzer-jump-through-null                                 -Wno-analyzer-malloc-leak\n-Wno-analyzer-mismatching-deallocation                        -Wno-analyzer-null-argument\n-Wno-analyzer-null-dereference                                -Wno-analyzer-out-of-bounds\n-Wno-analyzer-possible-null-argument              -Wno-analyzer-possible-null-dereference\n-Wno-analyzer-putenv-of-auto-var                       -Wno-analyzer-shift-count-negative\n-Wno-analyzer-shift-count-overflow                      -Wno-analyzer-stale-setjmp-buffer\n-Wno-analyzer-tainted-allocation-size                     -Wno-analyzer-tainted-assertion\n-Wno-analyzer-tainted-array-index                           -Wno-analyzer-tainted-divisor\n-Wno-analyzer-tainted-offset      -Wno-analyzer-tainted-size       -Wanalyzer-too-complex\n-Wno-analyzer-unsafe-call-within-signal-handler              -Wno-analyzer-use-after-free\n-Wno-analyzer-use-of-pointer-in-stale-stack-frame\n-Wno-analyzer-use-of-uninitialized-value               -Wno-analyzer-va-arg-type-mismatch\n-Wno-analyzer-va-list-exhausted                                -Wno-analyzer-va-list-leak\n-Wno-analyzer-va-list-use-after-va-end                       -Wno-analyzer-write-to-const\n-Wno-analyzer-write-to-string-literal\n\nC and Objective-C-only Warning Options\n-Wbad-function-cast             -Wmissing-declarations           -Wmissing-parameter-type\n-Wmissing-prototypes   -Wnested-externs  -Wold-style-declaration   -Wold-style-definition\n-Wstrict-prototypes                 -Wtraditional                -Wtraditional-conversion\n-Wdeclaration-after-statement  -Wpointer-sign\n\nDebugging Options\n-g     -glevel     -gdwarf     -gdwarf-version    -gbtf    -gctf     -gctflevel     -ggdb\n-grecord-gcc-switches     -gno-record-gcc-switches    -gstrict-dwarf    -gno-strict-dwarf\n-gas-loc-support    -gno-as-loc-support   -gas-locview-support    -gno-as-locview-support\n-gcolumn-info      -gno-column-info      -gdwarf32     -gdwarf64    -gstatement-frontiers\n-gno-statement-frontiers     -gvariable-location-views       -gno-variable-location-views\n-ginternal-reset-location-views     -gno-internal-reset-location-views    -ginline-points\n-gno-inline-points -gvms -gz[=type]  -gsplit-dwarf   -gdescribe-dies   -gno-describe-dies\n-fdebug-prefix-map=old=new     -fdebug-types-section    -fno-eliminate-unused-debug-types\n-femit-struct-debug-baseonly                                  -femit-struct-debug-reduced\n-femit-struct-debug-detailed[=spec-list]              -fno-eliminate-unused-debug-symbols\n-femit-class-debug-always  -fno-merge-debug-strings   -fno-dwarf2-cfi-asm  -fvar-tracking\n-fvar-tracking-assignments\n\nOptimization Options\n-faggressive-loop-optimizations                       -falign-functions[=n[:m:[n2[:m2]]]]\n-falign-jumps[=n[:m:[n2[:m2]]]]                          -falign-labels[=n[:m:[n2[:m2]]]]\n-falign-loops[=n[:m:[n2[:m2]]]]        -fno-allocation-dce       -fallow-store-data-races\n-fassociative-math       -fauto-profile        -fauto-profile[=path]       -fauto-inc-dec\n-fbranch-probabilities   -fcaller-saves   -fcombine-stack-adjustments    -fconserve-stack\n-fcompare-elim  -fcprop-registers  -fcrossjumping  -fcse-follow-jumps   -fcse-skip-blocks\n-fcx-fortran-rules    -fcx-limited-range    -fdata-sections     -fdce    -fdelayed-branch\n-fdelete-null-pointer-checks         -fdevirtualize          -fdevirtualize-speculatively\n-fdevirtualize-at-ltrans   -fdse  -fearly-inlining   -fipa-sra  -fexpensive-optimizations\n-ffat-lto-objects         -ffast-math          -ffinite-math-only           -ffloat-store\n-fexcess-precision=style    -ffinite-loops    -fforward-propagate     -ffp-contract=style\n-ffunction-sections     -fgcse       -fgcse-after-reload       -fgcse-las       -fgcse-lm\n-fgraphite-identity  -fgcse-sm   -fhoist-adjacent-loads  -fif-conversion -fif-conversion2\n-findirect-inlining -finline-functions  -finline-functions-called-once   -finline-limit=n\n-finline-small-functions  -fipa-modref  -fipa-cp   -fipa-cp-clone -fipa-bit-cp  -fipa-vrp\n-fipa-pta  -fipa-profile  -fipa-pure-const  -fipa-reference   -fipa-reference-addressable\n-fipa-stack-alignment     -fipa-icf     -fira-algorithm=algorithm   -flive-patching=level\n-fira-region=region  -fira-hoist-pressure -fira-loop-pressure   -fno-ira-share-save-slots\n-fno-ira-share-spill-slots                          -fisolate-erroneous-paths-dereference\n-fisolate-erroneous-paths-attribute           -fivopts            -fkeep-inline-functions\n-fkeep-static-functions          -fkeep-static-consts          -flimit-function-alignment\n-flive-range-shrinkage      -floop-block       -floop-interchange       -floop-strip-mine\n-floop-unroll-and-jam   -floop-nest-optimize  -floop-parallelize-all   -flra-remat  -flto\n-flto-compression-level  -flto-partition=alg    -fmerge-all-constants   -fmerge-constants\n-fmodulo-sched   -fmodulo-sched-allow-regmoves -fmove-loop-invariants  -fmove-loop-stores\n-fno-branch-count-reg  -fno-defer-pop    -fno-fp-int-builtin-inexact    -fno-function-cse\n-fno-guess-branch-probability  -fno-inline  -fno-math-errno  -fno-peephole -fno-peephole2\n-fno-printf-return-value     -fno-sched-interblock   -fno-sched-spec    -fno-signed-zeros\n-fno-toplevel-reorder           -fno-trapping-math           -fno-zero-initialized-in-bss\n-fomit-frame-pointer      -foptimize-sibling-calls    -fpartial-inlining     -fpeel-loops\n-fpredictive-commoning    -fprefetch-loop-arrays    -fprofile-correction    -fprofile-use\n-fprofile-use=path               -fprofile-partial-training              -fprofile-values\n-fprofile-reorder-functions      -freciprocal-math        -free        -frename-registers\n-freorder-blocks    -freorder-blocks-algorithm=algorithm   -freorder-blocks-and-partition\n-freorder-functions      -frerun-cse-after-loop       -freschedule-modulo-scheduled-loops\n-frounding-math   -fsave-optimization-record  -fsched2-use-superblocks   -fsched-pressure\n-fsched-spec-load        -fsched-spec-load-dangerous        -fsched-stalled-insns-dep[=n]\n-fsched-stalled-insns[=n]     -fsched-group-heuristic     -fsched-critical-path-heuristic\n-fsched-spec-insn-heuristic       -fsched-rank-heuristic      -fsched-last-insn-heuristic\n-fsched-dep-count-heuristic    -fschedule-fusion    -fschedule-insns    -fschedule-insns2\n-fsection-anchors -fselective-scheduling  -fselective-scheduling2  -fsel-sched-pipelining\n-fsel-sched-pipelining-outer-loops         -fsemantic-interposition         -fshrink-wrap\n-fshrink-wrap-separate            -fsignaling-nans            -fsingle-precision-constant\n-fsplit-ivs-in-unroller        -fsplit-loops       -fsplit-paths       -fsplit-wide-types\n-fsplit-wide-types-early   -fssa-backprop   -fssa-phiopt  -fstdarg-opt    -fstore-merging\n-fstrict-aliasing    -fipa-strict-aliasing   -fthread-jumps    -ftracer    -ftree-bit-ccp\n-ftree-builtin-call-dce   -ftree-ccp   -ftree-ch  -ftree-coalesce-vars   -ftree-copy-prop\n-ftree-dce      -ftree-dominator-opts     -ftree-dse      -ftree-forwprop      -ftree-fre\n-fcode-hoisting       -ftree-loop-if-convert         -ftree-loop-im        -ftree-phiprop\n-ftree-loop-distribution        -ftree-loop-distribute-patterns       -ftree-loop-ivcanon\n-ftree-loop-linear  -ftree-loop-optimize -ftree-loop-vectorize -ftree-parallelize-loops=n\n-ftree-pre  -ftree-partial-pre  -ftree-pta -ftree-reassoc  -ftree-scev-cprop  -ftree-sink\n-ftree-slsr    -ftree-sra    -ftree-switch-conversion     -ftree-tail-merge    -ftree-ter\n-ftree-vectorize      -ftree-vrp      -ftrivial-auto-var-init     -funconstrained-commons\n-funit-at-a-time     -funroll-all-loops    -funroll-loops     -funsafe-math-optimizations\n-funswitch-loops  -fipa-ra   -fvariable-expansion-in-unroller   -fvect-cost-model   -fvpt\n-fweb   -fwhole-program    -fwpa    -fuse-linker-plugin   -fzero-call-used-regs   --param\nname=value -O  -O0  -O1  -O2  -O3  -Os  -Ofast  -Og  -Oz\n\nProgram Instrumentation Options\n-p      -pg      -fprofile-arcs      --coverage     -ftest-coverage    -fprofile-abs-path\n-fprofile-dir=path   -fprofile-generate   -fprofile-generate=path  -fprofile-info-section\n-fprofile-info-section=name         -fprofile-note=path        -fprofile-prefix-path=path\n-fprofile-update=method    -fprofile-filter-files=regex     -fprofile-exclude-files=regex\n-fprofile-reproducible=[multithreaded|parallel-runs|serial]              -fsanitize=style\n-fsanitize-recover   -fsanitize-recover=style   -fsanitize-trap     -fsanitize-trap=style\n-fasan-shadow-offset=number                                 -fsanitize-sections=s1,s2,...\n-fsanitize-undefined-trap-on-error                                         -fbounds-check\n-fcf-protection=[full|branch|return|none|check]                         -fharden-compares\n-fharden-conditional-branches          -fstack-protector            -fstack-protector-all\n-fstack-protector-strong             -fstack-protector-explicit             -fstack-check\n-fstack-limit-register=reg   -fstack-limit-symbol=sym   -fno-stack-limit    -fsplit-stack\n-fvtable-verify=[std|preinit|none]   -fvtv-counts    -fvtv-debug   -finstrument-functions\n-finstrument-functions-once      -finstrument-functions-exclude-function-list=sym,sym,...\n-finstrument-functions-exclude-file-list=file,file,...  -fprofile-prefix-map=old=new\n\nPreprocessor Options\n-Aquestion=answer  -A-question[=answer]  -C   -CC  -Dmacro[=defn] -dD  -dI  -dM  -dN  -dU\n-fdebug-cpp     -fdirectives-only     -fdollars-in-identifiers     -fexec-charset=charset\n-fextended-identifiers            -finput-charset=charset            -flarge-source-files\n-fmacro-prefix-map=old=new    -fmax-include-depth=depth     -fno-canonical-system-headers\n-fpch-deps   -fpch-preprocess  -fpreprocessed   -ftabstop=width   -ftrack-macro-expansion\n-fwide-exec-charset=charset  -fworking-directory -H  -imacros file  -include file -M  -MD\n-MF  -MG  -MM  -MMD  -MP  -MQ  -MT -Mno-modules -no-integrated-cpp  -P  -pthread   -remap\n-traditional   -traditional-cpp   -trigraphs  -Umacro   -undef -Wp,option  -Xpreprocessor\noption\n\nAssembler Options\n-Wa,option  -Xassembler option\n\nLinker Options\nobject-file-name   -fuse-ld=linker   -llibrary  -nostartfiles   -nodefaultlibs    -nolibc\n-nostdlib   -nostdlib++ -e entry  --entry=entry -pie  -pthread  -r  -rdynamic -s  -static\n-static-pie    -static-libgcc    -static-libstdc++    -static-libasan     -static-libtsan\n-static-liblsan    -static-libubsan   -shared    -shared-libgcc    -symbolic   -T  script\n-Wl,option  -Xlinker option -u symbol  -z keyword\n\nDirectory Options\n-Bprefix  -Idir   -I-  -idirafter  dir  -imacros  file   -imultilib  dir  -iplugindir=dir\n-iprefix   file   -iquote   dir    -isysroot   dir    -isystem   dir   -iwithprefix   dir\n-iwithprefixbefore  dir  -Ldir   -no-canonical-prefixes   --no-sysroot-suffix   -nostdinc\n-nostdinc++  --sysroot=dir\n\nCode Generation Options\n-fcall-saved-reg    -fcall-used-reg   -ffixed-reg    -fexceptions   -fnon-call-exceptions\n-fdelete-dead-exceptions   -funwind-tables  -fasynchronous-unwind-tables  -fno-gnu-unique\n-finhibit-size-directive   -fcommon   -fno-ident -fpcc-struct-return  -fpic  -fPIC  -fpie\n-fPIE  -fno-plt -fno-jump-tables -fno-bit-tests -frecord-gcc-switches -freg-struct-return\n-fshort-enums   -fshort-wchar   -fverbose-asm    -fpack-struct[=n]   -fleading-underscore\n-ftls-model=model     -fstack-reuse=reuselevel     -ftrampolines     -ftrapv     -fwrapv\n-fvisibility=[default|internal|hidden|protected]              -fstrict-volatile-bitfields\n-fsync-libcalls\n\nDeveloper Options\n-dletters        -dumpspecs        -dumpmachine        -dumpversion      -dumpfullversion\n-fcallgraph-info[=su,da]  -fchecking   -fchecking=n  -fdbg-cnt-list    -fdbg-cnt=counter-\nvalue-list -fdisable-ipa-passname -fdisable-rtl-passname -fdisable-rtl-pass-name=range-\nlist     -fdisable-tree-passname     -fdisable-tree-pass-name=range-list    -fdump-debug\n-fdump-earlydebug     -fdump-noaddr       -fdump-unnumbered       -fdump-unnumbered-links\n-fdump-final-insns[=file]     -fdump-ipa-all      -fdump-ipa-cgraph     -fdump-ipa-inline\n-fdump-lang-all               -fdump-lang-switch               -fdump-lang-switch-options\n-fdump-lang-switch-options=filename             -fdump-passes             -fdump-rtl-pass\n-fdump-rtl-pass=filename     -fdump-statistics     -fdump-tree-all     -fdump-tree-switch\n-fdump-tree-switch-options   -fdump-tree-switch-options=filename   -fcompare-debug[=opts]\n-fcompare-debug-second -fenable-kind-pass  -fenable-kind-pass=range-list  -fira-verbose=n\n-flto-report    -flto-report-wpa    -fmem-report-wpa  -fmem-report   -fpre-ipa-mem-report\n-fpost-ipa-mem-report      -fopt-info        -fopt-info-options[=file]       -fmultiflags\n-fprofile-report      -frandom-seed=string      -fsched-verbose=n     -fsel-sched-verbose\n-fsel-sched-dump-cfg      -fsel-sched-pipelining-verbose      -fstats       -fstack-usage\n-ftime-report     -ftime-report-details    -fvar-tracking-assignments-toggle     -gtoggle\n-print-file-name=library          -print-libgcc-file-name          -print-multi-directory\n-print-multi-lib   -print-multi-os-directory -print-prog-name=program  -print-search-dirs\n-Q    -print-sysroot     -print-sysroot-headers-suffix    -save-temps     -save-temps=cwd\n-save-temps=obj  -time[=file]\n\nMachine-Dependent Options\nAArch64    Options    -mabi=name    -mbig-endian    -mlittle-endian   -mgeneral-regs-only\n-mcmodel=tiny    -mcmodel=small    -mcmodel=large    -mstrict-align     -mno-strict-align\n-momit-leaf-frame-pointer  -mtls-dialect=desc   -mtls-dialect=traditional -mtls-size=size\n-mfix-cortex-a53-835769         -mfix-cortex-a53-843419        -mlow-precision-recip-sqrt\n-mlow-precision-sqrt            -mlow-precision-div           -mpc-relative-literal-loads\n-msign-return-address=scope  -mbranch-protection=none|standard|pac-ret[+leaf  +b-key]|bti\n-mharden-sls=opts      -march=name      -mcpu=name      -mtune=name     -moverride=string\n-mverbose-cost-dump   -mstack-protector-guard=guard    -mstack-protector-guard-reg=sysreg\n-mstack-protector-guard-offset=offset -mtrack-speculation -moutline-atomics\n\nAdapteva  Epiphany  Options  -mhalf-reg-file   -mprefer-short-insn-regs -mbranch-cost=num\n-mcmove     -mnops=num     -msoft-cmpsf    -msplit-lohi     -mpost-inc      -mpost-modify\n-mstack-offset=num -mround-nearest  -mlong-calls  -mshort-calls  -msmall16 -mfp-mode=mode\n-mvect-double  -max-vect-align=num -msplit-vecmove-early  -m1reg-reg\n\nAMD GCN Options -march=gpu -mtune=gpu -mstack-size=bytes\n\nARC  Options  -mbarrel-shifter   -mjli-always  -mcpu=cpu   -mA6  -mARC600  -mA7  -mARC700\n-mdpfp  -mdpfp-compact  -mdpfp-fast  -mno-dpfp-lrsr -mea  -mno-mpy   -mmul32x16   -mmul64\n-matomic  -mnorm  -mspfp  -mspfp-compact  -mspfp-fast  -msimd  -msoft-float  -mswap -mcrc\n-mdsp-packa  -mdvbf  -mlock   -mmac-d16   -mmac-24   -mrtsc   -mswape  -mtelephony   -mxy\n-misize    -mannotate-align   -marclinux   -marclinuxprof  -mlong-calls   -mmedium-calls\n-msdata  -mirq-ctrl-saved -mrgf-banked-regs  -mlpc-width=width  -G  num  -mvolatile-cache\n-mtp-regno=regno     -malign-call     -mauto-modify-reg     -mbbit-peephole     -mno-brcc\n-mcase-vector-pcrel  -mcompact-casesi  -mno-cond-exec   -mearly-cbranchsi  -mexpand-adddi\n-mindexed-loads          -mlra          -mlra-priority-none        -mlra-priority-compact\n-mlra-priority-noncompact    -mmillicode   -mmixed-code     -mq-class     -mRcq     -mRcw\n-msize-level=level         -mtune=cpu         -mmultcost=num         -mcode-density-frame\n-munalign-prob-threshold=probability    -mmpy-option=multo   -mdiv-rem     -mcode-density\n-mll64  -mfpu=fpu  -mrf16  -mbranch-index\n\nARM     Options     -mapcs-frame      -mno-apcs-frame    -mabi=name    -mapcs-stack-check\n-mno-apcs-stack-check    -mapcs-reentrant     -mno-apcs-reentrant     -mgeneral-regs-only\n-msched-prolog     -mno-sched-prolog    -mlittle-endian    -mbig-endian   -mbe8    -mbe32\n-mfloat-abi=name -mfp16-format=name  -mthumb-interwork   -mno-thumb-interwork  -mcpu=name\n-march=name    -mfpu=name   -mtune=name    -mprint-tune-info  -mstructure-size-boundary=n\n-mabort-on-noreturn -mlong-calls  -mno-long-calls -msingle-pic-base  -mno-single-pic-base\n-mpic-register=reg -mnop-fun-dllimport -mpoke-function-name -mthumb  -marm   -mflip-thumb\n-mtpcs-frame   -mtpcs-leaf-frame -mcaller-super-interworking  -mcallee-super-interworking\n-mtp=name       -mtls-dialect=dialect       -mword-relocations       -mfix-cortex-m3-ldrd\n-mfix-cortex-a57-aes-1742098        -mfix-cortex-a72-aes-1655431       -munaligned-access\n-mneon-for-64bits       -mslow-flash-data       -masm-syntax-unified        -mrestrict-it\n-mverbose-cost-dump          -mpure-code         -mcmse         -mfix-cmse-cve-2021-35465\n-mstack-protector-guard=guard        -mstack-protector-guard-offset=offset        -mfdpic\n-mbranch-protection=none|standard|pac-ret[+leaf] [+bti]|bti[+pac-ret[+leaf]]\n\nAVR  Options  -mmcu=mcu  -mabsdata  -maccumulate-args -mbranch-cost=cost -mcall-prologues\n-mgas-isr-prologues     -mint8    -mdouble=bits     -mlong-double=bits     -mnflash=size\n-mno-interrupts    -mmain-is-OStask     -mrelax     -mrmw     -mstrict-X    -mtiny-stack\n-mfract-convert-truncate   -mshort-calls    -mskip-bug    -nodevicelib     -nodevicespecs\n-Waddr-space-convert  -Wmisspelled-isr\n\nBlackfin      Options     -mcpu=cpu[-sirevision]     -msim      -momit-leaf-frame-pointer\n-mno-omit-leaf-frame-pointer   -mspecld-anomaly    -mno-specld-anomaly    -mcsync-anomaly\n-mno-csync-anomaly    -mlow-64k    -mno-low64k    -mstack-check-l1    -mid-shared-library\n-mno-id-shared-library           -mshared-library-id=n           -mleaf-id-shared-library\n-mno-leaf-id-shared-library   -msep-data   -mno-sep-data   -mlong-calls   -mno-long-calls\n-mfast-fp  -minline-plt  -mmulticore  -mcorea  -mcoreb  -msdram -micplb\n\nC6X Options -mbig-endian  -mlittle-endian  -march=cpu -msim  -msdata=sdata-type\n\nCRIS Options -mcpu=cpu  -march=cpu -mtune=cpu  -mmax-stack-frame=n  -metrax4   -metrax100\n-mpdebug    -mcc-init    -mno-side-effects   -mstack-align   -mdata-align   -mconst-align\n-m32-bit   -m16-bit   -m8-bit   -mno-prologue-epilogue   -melf    -maout    -sim    -sim2\n-mmul-bug-workaround  -mno-mul-bug-workaround\n\nC-SKY Options -march=arch  -mcpu=cpu -mbig-endian  -EB  -mlittle-endian  -EL -mhard-float\n-msoft-float  -mfpu=fpu  -mdouble-float  -mfdivdu -mfloat-abi=name -melrw  -mistack  -mmp\n-mcp  -mcache  -msecurity  -mtrust -mdsp  -medsp  -mvdsp -mdiv  -msmart  -mhigh-registers\n-manchor  -mpushpop   -mmultiple-stld   -mconstpool  -mstack-size  -mccrt -mbranch-cost=n\n-mcse-cc  -msched-prolog -msim\n\nDarwin  Options  -allload   -allowableclient   -arch    -archerrorsfatal   -archonly\n-bindatload      -bundle      -bundleloader    -clientname     -compatibilityversion\n-currentversion  -deadstrip   -dependency-file    -dylibfile    -dylinkerinstallname\n-dynamic       -dynamiclib      -exportedsymbolslist     -filelist      -flatnamespace\n-forcecpusubtypeALL  -forceflatnamespace   -headerpadmaxinstallnames   -iframework\n-imagebase  -init  -installname  -keepprivateexterns -multimodule  -multiplydefined\n-multiplydefinedunused  -noallload    -nodeadstripinitsandterms  -nofixprebinding\n-nomultidefs        -noprebind        -noseglinkedit       -pagezerosize        -prebind\n-prebindalltwolevelmodules      -privatebundle      -readonlyrelocs      -sectalign\n-sectobjectsymbols   -whyload   -seg1addr  -sectcreate   -sectobjectsymbols    -sectorder\n-segaddr         -segsreadonlyaddr         -segsreadwriteaddr       -segaddrtable\n-segaddrtablefilename        -seglinkedit        -segprot         -segsreadonlyaddr\n-segsreadwriteaddr     -singlemodule      -static      -sublibrary     -subumbrella\n-twolevelnamespace         -umbrella         -undefined         -unexportedsymbolslist\n-weakreferencemismatches -whatsloaded  -F  -gused  -gfull  -mmacosx-version-min=version\n-mkernel  -mone-byte-bool\n\nDEC    Alpha    Options    -mno-fp-regs     -msoft-float    -mieee    -mieee-with-inexact\n-mieee-conformant  -mfp-trap-mode=mode    -mfp-rounding-mode=mode   -mtrap-precision=mode\n-mbuild-constants  -mcpu=cpu-type  -mtune=cpu-type -mbwx  -mmax  -mfix  -mcix -mfloat-vax\n-mfloat-ieee -mexplicit-relocs   -msmall-data   -mlarge-data  -msmall-text   -mlarge-text\n-mmemory-latency=time\n\neBPF  Options  -mbig-endian  -mlittle-endian  -mkernel=version -mframe-limit=bytes -mxbpf\n-mco-re -mno-co-re -mjmpext -mjmp32 -malu32 -mcpu=version\n\nFR30 Options -msmall-model  -mno-lsim\n\nFT32 Options -msim  -mlra  -mnodiv  -mft32b  -mcompress  -mnopm\n\nFRV Options -mgpr-32  -mgpr-64  -mfpr-32  -mfpr-64 -mhard-float  -msoft-float  -malloc-cc\n-mfixed-cc   -mdword   -mno-dword  -mdouble   -mno-double  -mmedia   -mno-media  -mmuladd\n-mno-muladd  -mfdpic    -minline-plt    -mgprel-ro    -multilib-library-pic   -mlinked-fp\n-mlong-calls    -malign-labels   -mlibrary-pic    -macc-4    -macc-8   -mpack   -mno-pack\n-mno-eflags  -mcond-move  -mno-cond-move  -moptimize-membar   -mno-optimize-membar  -mscc\n-mno-scc   -mcond-exec   -mno-cond-exec -mvliw-branch  -mno-vliw-branch -mmulti-cond-exec\n-mno-multi-cond-exec   -mnested-cond-exec  -mno-nested-cond-exec   -mtomcat-stats   -mTLS\n-mtls -mcpu=cpu\n\nGNU/Linux   Options   -mglibc   -muclibc   -mmusl   -mbionic   -mandroid  -tno-android-cc\n-tno-android-ld\n\nH8/300 Options -mrelax  -mh  -ms  -mn  -mexr  -mno-exr  -mint32  -malign-300\n\nHPPA Options  -march=architecture-type  -matomic-libcalls   -mbig-switch  -mcaller-copies\n-mdisable-fpregs   -mdisable-indexing  -mordered   -mfast-indirect-calls  -mgas  -mgnu-ld\n-mhp-ld  -mfixed-range=register-range   -mcoherent-ldcw   -mjump-in-delay    -mlinker-opt\n-mlong-calls       -mlong-load-store       -mno-atomic-libcalls       -mno-disable-fpregs\n-mno-disable-indexing      -mno-fast-indirect-calls      -mno-gas      -mno-jump-in-delay\n-mno-long-load-store -mno-portable-runtime  -mno-soft-float -mno-space-regs  -msoft-float\n-mpa-risc-1-0   -mpa-risc-1-1    -mpa-risc-2-0    -mportable-runtime  -mschedule=cpu-type\n-mspace-regs  -msoft-mult  -msio  -mwsio -munix=unix-std  -nolibdld  -static  -threads\n\nIA-64   Options   -mbig-endian     -mlittle-endian     -mgnu-as     -mgnu-ld     -mno-pic\n-mvolatile-asm-stop   -mregister-names   -msdata   -mno-sdata  -mconstant-gp   -mauto-pic\n-mfused-madd    -minline-float-divide-min-latency    -minline-float-divide-max-throughput\n-mno-inline-float-divide                                  -minline-int-divide-min-latency\n-minline-int-divide-max-throughput    -mno-inline-int-divide    -minline-sqrt-min-latency\n-minline-sqrt-max-throughput     -mno-inline-sqrt     -mdwarf2-asm      -mearly-stop-bits\n-mfixed-range=register-range   -mtls-size=tls-size   -mtune=cpu-type    -milp32    -mlp64\n-msched-br-data-spec   -msched-ar-data-spec  -msched-control-spec -msched-br-in-data-spec\n-msched-ar-in-data-spec              -msched-in-control-spec             -msched-spec-ldc\n-msched-spec-control-ldc                               -msched-prefer-non-data-spec-insns\n-msched-prefer-non-control-spec-insns                 -msched-stop-bits-after-every-cycle\n-msched-count-spec-in-critical-path                   -msel-sched-dont-check-control-spec\n-msched-fp-mem-deps-zero-cost                         -msched-max-memory-insns-hard-limit\n-msched-max-memory-insns=max-insns\n\nLM32     Options     -mbarrel-shift-enabled      -mdivide-enabled      -mmultiply-enabled\n-msign-extend-enabled  -muser-enabled\n\nLoongArch Options  -march=cpu-type   -mtune=cpu-type  -mabi=base-abi-type  -mfpu=fpu-type\n-msoft-float   -msingle-float   -mdouble-float   -mbranch-cost=n    -mcheck-zero-division\n-mno-check-zero-division    -mcond-move-int      -mno-cond-move-int     -mcond-move-float\n-mno-cond-move-float     -memcpy      -mno-memcpy     -mstrict-align    -mno-strict-align\n-mmax-inline-memcpy-size=n -mexplicit-relocs -mno-explicit-relocs  -mdirect-extern-access\n-mno-direct-extern-access -mcmodel=code-model -mrelax -mpass-mrelax-to-as\n\nM32R/D   Options   -m32r2    -m32rx    -m32r   -mdebug   -malign-loops   -mno-align-loops\n-missue-rate=number -mbranch-cost=number -mmodel=code-size-model-type  -msdata=sdata-type\n-mno-flush-func  -mflush-func=name -mno-flush-trap  -mflush-trap=number -G num\n\nM32C Options -mcpu=cpu  -msim  -memregs=number\n\nM680x0   Options   -march=arch    -mcpu=cpu   -mtune=tune  -m68000   -m68020   -m68020-40\n-m68020-60  -m68030  -m68040 -m68060  -mcpu32  -m5200  -m5206e   -m528x   -m5307   -m5407\n-mcfv4e   -mbitfield   -mno-bitfield   -mc68000   -mc68020  -mnobitfield  -mrtd  -mno-rtd\n-mdiv   -mno-div   -mshort  -mno-short   -mhard-float   -m68881   -msoft-float    -mpcrel\n-malign-int      -mstrict-align     -msep-data     -mno-sep-data    -mshared-library-id=n\n-mid-shared-library  -mno-id-shared-library -mxgot  -mno-xgot  -mlong-jump-table-offsets\n\nMCore   Options   -mhardlit    -mno-hardlit     -mdiv     -mno-div     -mrelax-immediates\n-mno-relax-immediates      -mwide-bitfields      -mno-wide-bitfields    -m4byte-functions\n-mno-4byte-functions  -mcallgraph-data -mno-callgraph-data  -mslow-bytes  -mno-slow-bytes\n-mno-lsim -mlittle-endian  -mbig-endian  -m210  -m340  -mstack-increment\n\nMicroBlaze  Options  -msoft-float   -mhard-float   -msmall-divides   -mcpu=cpu   -mmemcpy\n-mxl-soft-mul   -mxl-soft-div   -mxl-barrel-shift  -mxl-pattern-compare  -mxl-stack-check\n-mxl-gp-opt   -mno-clearbss   -mxl-multiply-high    -mxl-float-convert    -mxl-float-sqrt\n-mbig-endian           -mlittle-endian          -mxl-reorder          -mxl-mode-app-model\n-mpic-data-is-text-relative\n\nMIPS Options -EL  -EB  -march=arch  -mtune=arch -mips1  -mips2  -mips3   -mips4   -mips32\n-mips32r2   -mips32r3   -mips32r5  -mips32r6   -mips64   -mips64r2   -mips64r3  -mips64r5\n-mips64r6      -mips16       -mno-mips16       -mflip-mips16       -minterlink-compressed\n-mno-interlink-compressed -minterlink-mips16  -mno-interlink-mips16 -mabi=abi  -mabicalls\n-mno-abicalls  -mshared   -mno-shared   -mplt  -mno-plt  -mxgot  -mno-xgot -mgp32  -mgp64\n-mfp32    -mfpxx    -mfp64    -mhard-float    -msoft-float   -mno-float    -msingle-float\n-mdouble-float  -modd-spreg   -mno-odd-spreg  -mabs=mode   -mnan=encoding -mdsp  -mno-dsp\n-mdspr2  -mno-dspr2 -mmcu  -mmno-mcu -meva  -mno-eva -mvirt   -mno-virt  -mxpa   -mno-xpa\n-mcrc    -mno-crc   -mginv    -mno-ginv   -mmicromips    -mno-micromips  -mmsa   -mno-msa\n-mloongson-mmi   -mno-loongson-mmi  -mloongson-ext    -mno-loongson-ext   -mloongson-ext2\n-mno-loongson-ext2    -mfpu=fpu-type    -msmartmips     -mno-smartmips    -mpaired-single\n-mno-paired-single   -mdmx   -mno-mdmx  -mips3d   -mno-mips3d   -mmt    -mno-mt    -mllsc\n-mno-llsc  -mlong64  -mlong32  -msym32  -mno-sym32 -Gnum  -mlocal-sdata  -mno-local-sdata\n-mextern-sdata  -mno-extern-sdata  -mgpopt  -mno-gopt -membedded-data  -mno-embedded-data\n-muninit-const-in-rodata        -mno-uninit-const-in-rodata       -mcode-readable=setting\n-msplit-addresses      -mno-split-addresses    -mexplicit-relocs     -mno-explicit-relocs\n-mcheck-zero-division     -mno-check-zero-division    -mdivide-traps      -mdivide-breaks\n-mload-store-pairs    -mno-load-store-pairs   -munaligned-access    -mno-unaligned-access\n-mmemcpy  -mno-memcpy  -mlong-calls  -mno-long-calls -mmad  -mno-mad  -mimadd  -mno-imadd\n-mfused-madd  -mno-fused-madd  -nocpp -mfix-24k  -mno-fix-24k -mfix-r4000  -mno-fix-r4000\n-mfix-r4400  -mno-fix-r4400  -mfix-r5900   -mno-fix-r5900  -mfix-r10000   -mno-fix-r10000\n-mfix-rm7000  -mno-fix-rm7000 -mfix-vr4120  -mno-fix-vr4120 -mfix-vr4130  -mno-fix-vr4130\n-mfix-sb1      -mno-fix-sb1    -mflush-func=func     -mno-flush-func    -mbranch-cost=num\n-mbranch-likely      -mno-branch-likely     -mcompact-branches=policy     -mfp-exceptions\n-mno-fp-exceptions  -mvr4130-align   -mno-vr4130-align   -msynci   -mno-synci -mlxc1-sxc1\n-mno-lxc1-sxc1     -mmadd4     -mno-madd4     -mrelax-pic-calls      -mno-relax-pic-calls\n-mmcount-ra-address -mframe-header-opt  -mno-frame-header-opt\n\nMMIX Options -mlibfuncs  -mno-libfuncs  -mepsilon  -mno-epsilon  -mabi=gnu -mabi=mmixware\n-mzero-extend       -mknuthdiv       -mtoplevel-symbols      -melf       -mbranch-predict\n-mno-branch-predict       -mbase-addresses       -mno-base-addresses        -msingle-exit\n-mno-single-exit\n\nMN10300 Options -mmult-bug  -mno-mult-bug -mno-am33  -mam33  -mam33-2  -mam34 -mtune=cpu-\ntype -mreturn-pointer-on-d0 -mno-crt0  -mrelax  -mliw  -msetlb\n\nMoxie Options -meb  -mel  -mmul.x  -mno-crt0\n\nMSP430  Options  -msim   -masm-hex   -mmcu=  -mcpu=  -mlarge  -msmall  -mrelax -mwarn-mcu\n-mcode-region=   -mdata-region=   -msilicon-errata=    -msilicon-errata-warn=   -mhwmult=\n-minrt  -mtiny-printf  -mmax-inline-shift=\n\nNDS32 Options -mbig-endian  -mlittle-endian -mreduced-regs  -mfull-regs -mcmov  -mno-cmov\n-mext-perf    -mno-ext-perf  -mext-perf2   -mno-ext-perf2  -mext-string   -mno-ext-string\n-mv3push  -mno-v3push -m16bit   -mno-16bit  -misr-vector-size=num  -mcache-block-size=num\n-march=arch -mcmodel=code-model -mctor-dtor  -mrelax\n\nNios   II   Options   -G  num   -mgpopt=option   -mgpopt   -mno-gpopt  -mgprel-sec=regexp\n-mr0rel-sec=regexp  -mel   -meb  -mno-bypass-cache   -mbypass-cache   -mno-cache-volatile\n-mcache-volatile   -mno-fast-sw-div    -mfast-sw-div   -mhw-mul   -mno-hw-mul   -mhw-mulx\n-mno-hw-mulx       -mno-hw-div       -mhw-div      -mcustom-insn=N       -mno-custom-insn\n-mcustom-fpu-cfg=name -mhal  -msmallc  -msys-crt0=name  -msys-lib=name -march=arch  -mbmx\n-mno-bmx  -mcdx  -mno-cdx\n\nNvidia PTX Options -m64  -mmainkernel  -moptimize\n\nOpenRISC  Options  -mboard=name   -mnewlib  -mhard-mul  -mhard-div -msoft-mul  -msoft-div\n-msoft-float   -mhard-float   -mdouble-float  -munordered-float  -mcmov   -mror    -mrori\n-msext  -msfimm  -mshftimm -mcmodel=code-model\n\nPDP-11 Options -mfpu  -msoft-float  -mac0  -mno-ac0  -m40  -m45  -m10 -mint32  -mno-int16\n-mint16  -mno-int32 -msplit  -munix-asm  -mdec-asm  -mgnu-asm  -mlra\n\nPowerPC Options See RS/6000 and PowerPC Options.\n\nPRU Options -mmcu=mcu  -minrt  -mno-relax  -mloop -mabi=variant\n\nRISC-V   Options  -mbranch-cost=N-instruction  -mplt   -mno-plt  -mabi=ABI-string  -mfdiv\n-mno-fdiv -mdiv  -mno-div -misa-spec=ISA-spec-string -march=ISA-string  -mtune=processor-\nstring     -mpreferred-stack-boundary=num    -msmall-data-limit=N-bytes    -msave-restore\n-mno-save-restore      -mshorten-memrefs        -mno-shorten-memrefs       -mstrict-align\n-mno-strict-align        -mcmodel=medlow         -mcmodel=medany        -mexplicit-relocs\n-mno-explicit-relocs   -mrelax    -mno-relax   -mriscv-attribute     -mno-riscv-attribute\n-malign-data=type     -mbig-endian      -mlittle-endian     -mstack-protector-guard=guard\n-mstack-protector-guard-reg=reg     -mstack-protector-guard-offset=offset     -mcsr-check\n-mno-csr-check -minline-atomics  -mno-inline-atomics\n\nRL78  Options  -msim   -mmul=none   -mmul=g13   -mmul=g14  -mallregs -mcpu=g10  -mcpu=g13\n-mcpu=g14       -mg10       -mg13       -mg14      -m64bit-doubles        -m32bit-doubles\n-msave-mduc-in-interrupts\n\nRS/6000   and   PowerPC   Options   -mcpu=cpu-type   -mtune=cpu-type  -mcmodel=code-model\n-mpowerpc64 -maltivec  -mno-altivec -mpowerpc-gpopt  -mno-powerpc-gpopt  -mpowerpc-gfxopt\n-mno-powerpc-gfxopt -mmfcrf  -mno-mfcrf  -mpopcntb  -mno-popcntb  -mpopcntd  -mno-popcntd\n-mfprnd     -mno-fprnd    -mcmpb    -mno-cmpb    -mhard-dfp    -mno-hard-dfp   -mfull-toc\n-mminimal-toc  -mno-fp-in-toc  -mno-sum-in-toc -m64   -m32   -mxl-compat   -mno-xl-compat\n-mpe -malign-power  -malign-natural -msoft-float  -mhard-float  -mmultiple  -mno-multiple\n-mupdate      -mno-update     -mavoid-indexed-addresses      -mno-avoid-indexed-addresses\n-mfused-madd      -mno-fused-madd      -mbit-align      -mno-bit-align     -mstrict-align\n-mno-strict-align         -mrelocatable        -mno-relocatable         -mrelocatable-lib\n-mno-relocatable-lib -mtoc   -mno-toc   -mlittle   -mlittle-endian   -mbig   -mbig-endian\n-mdynamic-no-pic    -mswdiv    -msingle-pic-base   -mprioritize-restricted-insns=priority\n-msched-costly-dep=dependencetype -minsert-sched-nops=scheme -mcall-aixdesc  -mcall-eabi\n-mcall-freebsd -mcall-linux  -mcall-netbsd  -mcall-openbsd -mcall-sysv   -mcall-sysv-eabi\n-mcall-sysv-noeabi  -mtraceback=tracebacktype  -maix-struct-return  -msvr4-struct-return\n-mabi=abi-type  -msecure-plt  -mbss-plt -mlongcall  -mno-longcall  -mpltseq   -mno-pltseq\n-mblock-move-inline-limit=num                            -mblock-compare-inline-limit=num\n-mblock-compare-inline-loop-limit=num                        -mno-block-ops-unaligned-vsx\n-mstring-compare-inline-limit=num   -misel    -mno-isel   -mvrsave   -mno-vrsave  -mmulhw\n-mno-mulhw  -mdlmzb   -mno-dlmzb  -mprototype   -mno-prototype   -msim    -mmvme    -mads\n-myellowknife  -memb  -msdata -msdata=opt  -mreadonly-in-sdata  -mvxworks  -G num -mrecip\n-mrecip=opt   -mno-recip  -mrecip-precision -mno-recip-precision -mveclibabi=type  -mfriz\n-mno-friz        -mpointers-to-nested-functions         -mno-pointers-to-nested-functions\n-msave-toc-indirect     -mno-save-toc-indirect    -mpower8-fusion     -mno-mpower8-fusion\n-mpower8-vector  -mno-power8-vector -mcrypto  -mno-crypto  -mhtm  -mno-htm  -mquad-memory\n-mno-quad-memory    -mquad-memory-atomic    -mno-quad-memory-atomic   -mcompat-align-parm\n-mno-compat-align-parm       -mfloat128         -mno-float128         -mfloat128-hardware\n-mno-float128-hardware  -mgnu-attribute  -mno-gnu-attribute -mstack-protector-guard=guard\n-mstack-protector-guard-reg=reg     -mstack-protector-guard-offset=offset      -mprefixed\n-mno-prefixed   -mpcrel   -mno-pcrel   -mmma   -mno-mmma  -mrop-protect  -mno-rop-protect\n-mprivileged -mno-privileged\n\nRX  Options  -m64bit-doubles   -m32bit-doubles   -fpu   -nofpu  -mcpu=  -mbig-endian-data\n-mlittle-endian-data   -msmall-data  -msim   -mno-sim  -mas100-syntax   -mno-as100-syntax\n-mrelax     -mmax-constant-size=     -mint-register=      -mpid      -mallow-string-insns\n-mno-allow-string-insns -mjsr -mno-warn-multiple-fast-interrupts -msave-acc-in-interrupts\n\nS/390  and  zSeries  Options  -mtune=cpu-type  -march=cpu-type -mhard-float  -msoft-float\n-mhard-dfp  -mno-hard-dfp -mlong-double-64  -mlong-double-128 -mbackchain  -mno-backchain\n-mpacked-stack  -mno-packed-stack -msmall-exec  -mno-small-exec  -mmvcle  -mno-mvcle -m64\n-m31   -mdebug   -mno-debug   -mesa    -mzarch   -mhtm    -mvx    -mzvector   -mtpf-trace\n-mno-tpf-trace    -mtpf-trace-skip    -mno-tpf-trace-skip  -mfused-madd   -mno-fused-madd\n-mwarn-framesize         -mwarn-dynamicstack          -mstack-size          -mstack-guard\n-mhotpatch=halfwords,halfwords\n\nSH  Options  -m1   -m2   -m2e  -m2a-nofpu   -m2a-single-only  -m2a-single  -m2a -m3  -m3e\n-m4-nofpu  -m4-single-only  -m4-single   -m4  -m4a-nofpu   -m4a-single-only   -m4a-single\n-m4a   -m4al  -mb   -ml   -mdalign   -mrelax -mbigtable  -mfmovd  -mrenesas  -mno-renesas\n-mnomacsave -mieee  -mno-ieee   -mbitops   -misize   -minline-icinvalidate   -mpadstruct\n-mprefergot     -musermode     -multcost=number    -mdiv=strategy   -mdivsi3libfunc=name\n-mfixed-range=register-range    -maccumulate-outgoing-args    -matomic-model=atomic-model\n-mbranch-cost=num   -mzdcbranch   -mno-zdcbranch  -mcbranch-force-delay-slot -mfused-madd\n-mno-fused-madd  -mfsca  -mno-fsca  -mfsrra  -mno-fsrra -mpretend-cmove  -mtas\n\nSolaris  2  Options  -mclear-hwcap   -mno-clear-hwcap   -mimpure-text    -mno-impure-text\n-pthreads\n\nSPARC Options -mcpu=cpu-type -mtune=cpu-type -mcmodel=code-model -mmemory-model=mem-model\n-m32   -m64   -mapp-regs   -mno-app-regs  -mfaster-structs   -mno-faster-structs   -mflat\n-mno-flat    -mfpu     -mno-fpu      -mhard-float      -msoft-float     -mhard-quad-float\n-msoft-quad-float         -mstack-bias         -mno-stack-bias        -mstd-struct-return\n-mno-std-struct-return    -munaligned-doubles      -mno-unaligned-doubles     -muser-mode\n-mno-user-mode   -mv8plus    -mno-v8plus    -mvis   -mno-vis  -mvis2   -mno-vis2   -mvis3\n-mno-vis3 -mvis4  -mno-vis4  -mvis4b  -mno-vis4b -mcbcond  -mno-cbcond  -mfmaf  -mno-fmaf\n-mfsmuld  -mno-fsmuld -mpopc  -mno-popc  -msubxc   -mno-subxc  -mfix-at697f   -mfix-ut699\n-mfix-ut700  -mfix-gr712rc -mlra  -mno-lra\n\nSystem V Options -Qy  -Qn  -YP,paths  -Ym,dir\n\nV850    Options    -mlong-calls    -mno-long-calls    -mep    -mno-ep   -mprolog-function\n-mno-prolog-function   -mspace  -mtda=n   -msda=n   -mzda=n   -mapp-regs    -mno-app-regs\n-mdisable-callt   -mno-disable-callt  -mv850e2v3   -mv850e2   -mv850e1   -mv850es -mv850e\n-mv850   -mv850e3v5  -mloop  -mrelax  -mlong-jumps  -msoft-float  -mhard-float  -mgcc-abi\n-mrh850-abi -mbig-switch\n\nVAX Options -mg  -mgnu  -munix  -mlra\n\nVisium Options -mdebug  -msim  -mfpu  -mno-fpu  -mhard-float  -msoft-float -mcpu=cpu-type\n-mtune=cpu-type  -msv-mode  -muser-mode\n\nVMS Options -mvms-return-codes  -mdebug-main=prefix  -mmalloc64 -mpointer-size=size\n\nVxWorks Options -mrtp  -non-static  -Bstatic  -Bdynamic -Xbind-lazy  -Xbind-now\n\nx86      Options      -mtune=cpu-type       -march=cpu-type      -mtune-ctrl=feature-list\n-mdump-tune-features   -mno-default  -mfpmath=unit   -masm=dialect    -mno-fancy-math-387\n-mno-fp-ret-in-387    -m80387    -mhard-float    -msoft-float  -mno-wide-multiply   -mrtd\n-malign-double -mpreferred-stack-boundary=num -mincoming-stack-boundary=num -mcld  -mcx16\n-msahf  -mmovbe   -mcrc32  -mmwait  -mrecip   -mrecip=opt  -mvzeroupper   -mprefer-avx128\n-mprefer-vector-width=opt  -mmove-max=bits  -mstore-max=bits -mmmx  -msse  -msse2  -msse3\n-mssse3  -msse4.1  -msse4.2  -msse4   -mavx  -mavx2   -mavx512f   -mavx512pf   -mavx512er\n-mavx512cd   -mavx512vl  -mavx512bw  -mavx512dq  -mavx512ifma  -mavx512vbmi  -msha  -maes\n-mpclmul   -mfsgsbase   -mrdrnd    -mf16c    -mfma    -mpconfig    -mwbnoinvd   -mptwrite\n-mprefetchwt1   -mclflushopt   -mclwb   -mxsavec   -mxsaves  -msse4a   -m3dnow   -m3dnowa\n-mpopcnt  -mabm  -mbmi  -mtbm  -mfma4  -mxop  -madx   -mlzcnt   -mbmi2   -mfxsr   -mxsave\n-mxsaveopt   -mrtm   -mhle   -mlwp  -mmwaitx   -mclzero  -mpku  -mthreads  -mgfni  -mvaes\n-mwaitpkg  -mshstk  -mmanual-endbr   -mcet-switch   -mforce-indirect-call   -mavx512vbmi2\n-mavx512bf16    -menqcmd    -mvpclmulqdq     -mavx512bitalg     -mmovdiri     -mmovdir64b\n-mavx512vpopcntdq  -mavx5124fmaps   -mavx512vnni    -mavx5124vnniw    -mprfchw    -mrdpid\n-mrdseed    -msgx  -mavx512vp2intersect  -mserialize  -mtsxldtrk  -mamx-tile   -mamx-int8\n-mamx-bf16 -muintr -mhreset -mavxvnni -mavx512fp16 -mavxifma -mavxvnniint8 -mavxneconvert\n-mcmpccxadd -mamx-fp16  -mprefetchi  -mraoint  -mamx-complex  -mcldemote   -mms-bitfields\n-mno-align-stringops         -minline-all-stringops        -minline-stringops-dynamically\n-mstringop-strategy=alg         -mkl         -mwidekl          -mmemcpy-strategy=strategy\n-mmemset-strategy=strategy  -mpush-args  -maccumulate-outgoing-args  -m128bit-long-double\n-m96bit-long-double  -mlong-double-64  -mlong-double-80  -mlong-double-128  -mregparm=num\n-msseregparm  -mveclibabi=type   -mvect8-ret-in-mem  -mpc32   -mpc64   -mpc80   -mdaz-ftz\n-mstackrealign   -momit-leaf-frame-pointer     -mno-red-zone     -mno-tls-direct-seg-refs\n-mcmodel=code-model   -mabi=name   -maddress-mode=mode  -m32   -m64  -mx32  -m16  -miamcu\n-mlarge-data-threshold=num    -msse2avx     -mfentry     -mrecord-mcount     -mnop-mcount\n-m8bit-idiv     -minstrument-return=type     -mfentry-name=name     -mfentry-section=name\n-mavx256-split-unaligned-load       -mavx256-split-unaligned-store      -malign-data=type\n-mstack-protector-guard=guard                             -mstack-protector-guard-reg=reg\n-mstack-protector-guard-offset=offset               -mstack-protector-guard-symbol=symbol\n-mgeneral-regs-only  -mcall-ms2sysv-xlogues -mrelax-cmpxchg-loop -mindirect-branch=choice\n-mfunction-return=choice          -mindirect-branch-register          -mharden-sls=choice\n-mindirect-branch-cs-prefix -mneeded -mno-direct-extern-access  -munroll-only-small-loops\n-mlam=choice\n\nx86 Windows Options -mconsole  -mcygwin  -mno-cygwin  -mdll -mnop-fun-dllimport  -mthread\n-municode  -mwin32  -mwindows  -fno-set-stack-executable\n\nXstormy16 Options -msim\n\nXtensa  Options  -mconst16   -mno-const16  -mfused-madd   -mno-fused-madd  -mforce-no-pic\n-mserialize-volatile            -mno-serialize-volatile           -mtext-section-literals\n-mno-text-section-literals     -mauto-litpools      -mno-auto-litpools     -mtarget-align\n-mno-target-align -mlongcalls  -mno-longcalls -mabi=abi-type -mextra-l32r-costs=cycles\n\nzSeries Options See S/390 and zSeries Options.\n"
                },
                {
                    "name": "Options Controlling the Kind of Output",
                    "content": "Compilation can involve up to four stages: preprocessing, compilation  proper,  assembly  and\nlinking,  always  in that order.  GCC is capable of preprocessing and compiling several files\neither into several assembler input files, or  into  one  assembler  input  file;  then  each\nassembler  input  file  produces  an  object  file, and linking combines all the object files\n(those newly compiled, and those specified as input) into an executable file.\n\nFor any given input file, the file name suffix determines what kind of compilation is done:\n\nfile.c\nC source code that must be preprocessed.\n\nfile.i\nC source code that should not be preprocessed.\n\nfile.ii\nC++ source code that should not be preprocessed.\n\nfile.m\nObjective-C source code.  Note that you must link with the libobjc  library  to  make  an\nObjective-C program work.\n\nfile.mi\nObjective-C source code that should not be preprocessed.\n\nfile.mm\nfile.M\nObjective-C++  source  code.  Note that you must link with the libobjc library to make an\nObjective-C++ program work.  Note that .M refers to a literal capital M.\n\nfile.mii\nObjective-C++ source code that should not be preprocessed.\n\nfile.h\nC, C++, Objective-C or Objective-C++ header file to be turned into a  precompiled  header\n(default),  or  C, C++ header file to be turned into an Ada spec (via the -fdump-ada-spec\nswitch).\n\nfile.cc\nfile.cp\nfile.cxx\nfile.cpp\nfile.CPP\nfile.c++\nfile.C\nC++ source code that must be preprocessed.  Note that in .cxx, the last two letters  must\nboth be literally x.  Likewise, .C refers to a literal capital C.\n\nfile.mm\nfile.M\nObjective-C++ source code that must be preprocessed.\n\nfile.mii\nObjective-C++ source code that should not be preprocessed.\n\nfile.hh\nfile.H\nfile.hp\nfile.hxx\nfile.hpp\nfile.HPP\nfile.h++\nfile.tcc\nC++ header file to be turned into a precompiled header or Ada spec.\n\nfile.f\nfile.for\nfile.ftn\nFixed form Fortran source code that should not be preprocessed.\n\nfile.F\nfile.FOR\nfile.fpp\nfile.FPP\nfile.FTN\nFixed  form  Fortran  source  code  that  must  be  preprocessed  (with  the  traditional\npreprocessor).\n\nfile.f90\nfile.f95\nfile.f03\nfile.f08\nFree form Fortran source code that should not be preprocessed.\n\nfile.F90\nfile.F95\nfile.F03\nfile.F08\nFree  form  Fortran  source  code  that  must  be  preprocessed  (with  the   traditional\npreprocessor).\n\nfile.go\nGo source code.\n\nfile.d\nD source code.\n\nfile.di\nD interface file.\n\nfile.dd\nD documentation code (Ddoc).\n\nfile.ads\nAda  source  code  file  that  contains  a  library  unit declaration (a declaration of a\npackage, subprogram, or generic, or a generic instantiation), or a library unit  renaming\ndeclaration  (a  package,  generic,  or subprogram renaming declaration).  Such files are\nalso called specs.\n\nfile.adb\nAda source code file containing a library unit body (a subprogram or package body).  Such\nfiles are also called bodies.\n\nfile.s\nAssembler code.\n\nfile.S\nfile.sx\nAssembler code that must be preprocessed.\n\nother\nAn object file to be fed straight into linking.  Any file name with no recognized  suffix\nis treated this way.\n\nYou can specify the input language explicitly with the -x option:\n"
                },
                {
                    "name": "-x _",
                    "content": "Specify  explicitly  the  language for the following input files (rather than letting the\ncompiler choose a default based on the file name suffix).  This  option  applies  to  all\nfollowing input files until the next -x option.  Possible values for language are:\n\nc  c-header  cpp-output\nc++  c++-header  c++-system-header c++-user-header c++-cpp-output\nobjective-c  objective-c-header  objective-c-cpp-output\nobjective-c++ objective-c++-header objective-c++-cpp-output\nassembler  assembler-with-cpp\nada\nd\nf77  f77-cpp-input f95  f95-cpp-input\ngo\n",
                    "flag": "-x"
                },
                {
                    "name": "-x none",
                    "content": "Turn  off any specification of a language, so that subsequent files are handled according\nto their file name suffixes (as they are if -x has not been used at all).\n\nIf you only want some of the stages of compilation, you can use -x (or filename suffixes)  to\ntell  gcc  where  to start, and one of the options -c, -S, or -E to say where gcc is to stop.\nNote that some combinations (for example, -x cpp-output -E) instruct gcc  to  do  nothing  at\nall.\n",
                    "flag": "-x"
                },
                {
                    "name": "-c",
                    "content": "done.  The ultimate output is in the form of an object file for each source file.\n\nBy default, the object file name for a source file is made by replacing  the  suffix  .c,\n.i, .s, etc., with .o.\n\nUnrecognized input files, not requiring compilation or assembly, are ignored.\n",
                    "flag": "-c"
                },
                {
                    "name": "-S",
                    "content": "of an assembler code file for each non-assembler input file specified.\n\nBy default, the assembler file name for a source file is made by replacing the suffix .c,\n.i, etc., with .s.\n\nInput files that don't require compilation are ignored.\n",
                    "flag": "-S"
                },
                {
                    "name": "-E",
                    "content": "form of preprocessed source code, which is sent to the standard output.\n\nInput files that don't require preprocessing are ignored.\n",
                    "flag": "-E"
                },
                {
                    "name": "-o _",
                    "content": "Place the primary output in file file.  This applies to whatever sort of output is  being\nproduced,  whether  it  be  an  executable  file,  an  object  file, an assembler file or\npreprocessed C code.\n\nIf -o is not specified, the default is to put an executable file  in  a.out,  the  object\nfile  for source.suffix in source.o, its assembler file in source.s, a precompiled header\nfile in source.suffix.gch, and all preprocessed C source on standard output.\n\nThough -o names only the primary output, it also affects the naming of auxiliary and dump\noutputs.  See the examples below.  Unless overridden, both  auxiliary  outputs  and  dump\noutputs  are  placed  in the same directory as the primary output.  In auxiliary outputs,\nthe suffix of the input file is replaced with that of the auxiliary output file type;  in\ndump  outputs,  the  suffix  of  the  dump file is appended to the input file suffix.  In\ncompilation commands, the base name of both auxiliary and dump outputs  is  that  of  the\nprimary  output;  in  compile  and  link  commands,  the  primary  output name, minus the\nexecutable suffix, is combined with the input file name.  If both  share  the  same  base\nname,  disregarding  the  suffix,  the  result  of  the  combination  is  that base name,\notherwise, they are concatenated, separated by a dash.\n\ngcc -c foo.c ...\n\nwill use foo.o as the primary output, and place aux outputs and dumps next to  it,  e.g.,\naux file foo.dwo for -gsplit-dwarf, and dump file foo.c.???r.final for -fdump-rtl-final.\n\nIf  a  non-linker output file is explicitly specified, aux and dump files by default take\nthe same base name:\n\ngcc -c foo.c -o dir/foobar.o ...\n\nwill name aux outputs dir/foobar.* and dump outputs dir/foobar.c.*.\n\nA linker output will instead prefix aux and dump outputs:\n\ngcc foo.c bar.c -o dir/foobar ...\n\nwill generally name aux outputs dir/foobar-foo.* and dir/foobar-bar.*, and  dump  outputs\ndir/foobar-foo.c.* and dir/foobar-bar.c.*.\n\nThe  one  exception  to  the  above  is when the executable shares the base name with the\nsingle input:\n\ngcc foo.c -o dir/foo ...\n\nin which case aux outputs are named dir/foo.* and dump outputs named dir/foo.c.*.\n\nThe location and the names of auxiliary and dump outputs can be adjusted by  the  options\n-dumpbase, -dumpbase-ext, -dumpdir, -save-temps=cwd, and -save-temps=obj.\n",
                    "flag": "-o"
                },
                {
                    "name": "-dumpbase _",
                    "content": "This  option  sets the base name for auxiliary and dump output files.  It does not affect\nthe name of the primary output file.   Intermediate  outputs,  when  preserved,  are  not\nregarded as primary outputs, but as auxiliary outputs:\n\ngcc -save-temps -S foo.c\n\nsaves  the  (no  longer)  temporary  preprocessed file in foo.i, and then compiles to the\n(implied) output file foo.s, whereas:\n\ngcc -save-temps -dumpbase save-foo -c foo.c\n\npreprocesses to  in  save-foo.i,  compiles  to  save-foo.s  (now  an  intermediate,  thus\nauxiliary output), and then assembles to the (implied) output file foo.o.\n\nAbsent  this option, dump and aux files take their names from the input file, or from the\n(non-linker) output file, if one is explicitly specified: dump output files  (e.g.  those\nrequested  by  -fdump-*  options) with the input name suffix, and aux output files (those\nrequested   by   other   non-dump   options,   e.g.    \"-save-temps\",    \"-gsplit-dwarf\",\n\"-fcallgraph-info\") without it.\n\nSimilar  suffix  differentiation  of dump and aux outputs can be attained for explicitly-\ngiven -dumpbase basename.suf by also specifying -dumpbase-ext .suf.\n\nIf  dumpbase  is  explicitly  specified  with  any  directory  component,   any   dumppfx\nspecification  (e.g.  -dumpdir  or -save-temps=*) is ignored, and instead of appending to\nit, dumpbase fully overrides it:\n\ngcc foo.c -c -o dir/foo.o -dumpbase alt/foo \\\n-dumpdir pfx- -save-temps=cwd ...\n\ncreates auxiliary and dump outputs named alt/foo.*,  disregarding  dir/  in  -o,  the  ./\nprefix implied by -save-temps=cwd, and pfx- in -dumpdir.\n\nWhen  -dumpbase is specified in a command that compiles multiple inputs, or that compiles\nand then links, it may be combined with dumppfx, as specified under -dumpdir.  Then, each\ninput file is compiled using the combined dumppfx, and default values  for  dumpbase  and\nauxdropsuf are computed for each input file:\n\ngcc foo.c bar.c -c -dumpbase main ...\n\ncreates foo.o and bar.o as primary outputs, and avoids overwriting the auxiliary and dump\noutputs  by  using  the  dumpbase  as a prefix, creating auxiliary and dump outputs named\nmain-foo.*  and main-bar.*.\n\nAn empty string specified as dumpbase avoids the influence of the output basename in  the\nnaming of auxiliary and dump outputs during compilation, computing default values :\n\ngcc -c foo.c -o dir/foobar.o -dumpbase \" ...\n\nwill  name  aux outputs dir/foo.* and dump outputs dir/foo.c.*.  Note how their basenames\nare taken from the input name, but the directory still defaults to that of the output.\n\nThe empty-string dumpbase does not prevent the use of the  output  basename  for  outputs\nduring linking:\n\ngcc foo.c bar.c -o dir/foobar -dumpbase \" -flto ...\n\nThe  compilation of the source files will name auxiliary outputs dir/foo.* and dir/bar.*,\nand dump outputs dir/foo.c.* and dir/bar.c.*.  LTO recompilation during linking will  use\ndir/foobar. as the prefix for dumps and auxiliary files.\n"
                },
                {
                    "name": "-dumpbase-ext _",
                    "content": "When  forming  the  name  of  an  auxiliary  (but  not a dump) output file, drop trailing\nauxdropsuf from dumpbase before appending any suffixes.  If not  specified,  this  option\ndefaults  to  the  suffix  of a default dumpbase, i.e., the suffix of the input file when\n-dumpbase is not present in the command line, or dumpbase is combined with dumppfx.\n\ngcc foo.c -c -o dir/foo.o -dumpbase x-foo.c -dumpbase-ext .c ...\n\ncreates dir/foo.o as the main output, and generates  auxiliary  outputs  in  dir/x-foo.*,\ntaking  the location of the primary output, and dropping the .c suffix from the dumpbase.\nDump outputs retain the suffix: dir/x-foo.c.*.\n\nThis option is disregarded if it does not match  the  suffix  of  a  specified  dumpbase,\nexcept  as  an alternative to the executable suffix when appending the linker output base\nname to dumppfx, as specified below:\n\ngcc foo.c bar.c -o main.out -dumpbase-ext .out ...\n\ncreates main.out as the primary output, and avoids overwriting  the  auxiliary  and  dump\noutputs  by  using  the  executable name minus auxdropsuf as a prefix, creating auxiliary\noutputs  named  main-foo.*  and  main-bar.*  and  dump  outputs  named  main-foo.c.*  and\nmain-bar.c.*.\n"
                },
                {
                    "name": "-dumpdir _",
                    "content": "When forming the name of an auxiliary or dump output file, use dumppfx as a prefix:\n\ngcc -dumpdir pfx- -c foo.c ...\n\ncreates foo.o as the primary output, and auxiliary outputs named pfx-foo.*, combining the\ngiven  dumppfx with the default dumpbase derived from the default primary output, derived\nin turn from the input name.  Dump outputs also take the input name suffix: pfx-foo.c.*.\n\nIf dumppfx is to be used as a directory name, it must end with a directory separator:\n\ngcc -dumpdir dir/ -c foo.c -o obj/bar.o ...\n\ncreates obj/bar.o as the primary output, and auxiliary outputs named dir/bar.*, combining\nthe given dumppfx with the default dumpbase derived from the primary output  name.   Dump\noutputs also take the input name suffix: dir/bar.c.*.\n\nIt  defaults to the location of the output file, unless the output file is a special file\nlike \"/dev/null\". Options -save-temps=cwd and -save-temps=obj override this default, just\nlike an explicit -dumpdir option.  In case multiple such options are given, the last  one\nprevails:\n\ngcc -dumpdir pfx- -c foo.c -save-temps=obj ...\n\noutputs  foo.o,  with  auxiliary  outputs named foo.* because -save-temps=* overrides the\ndumppfx given by the earlier -dumpdir option.  It  does  not  matter  that  =obj  is  the\ndefault  for  -save-temps,  nor  that  the  output  directory  is  implicitly the current\ndirectory.  Dump outputs are named foo.c.*.\n\nWhen compiling from multiple input files, if -dumpbase is specified,  dumpbase,  minus  a\nauxdropsuf  suffix,  and a dash are appended to (or override, if containing any directory\ncomponents) an explicit or defaulted dumppfx, so that each of the  multiple  compilations\ngets differently-named aux and dump outputs.\n\ngcc foo.c bar.c -c -dumpdir dir/pfx- -dumpbase main ...\n\noutputs auxiliary dumps to dir/pfx-main-foo.* and dir/pfx-main-bar.*, appending dumpbase-\nto  dumppfx.   Dump  outputs  retain  the  input  file  suffix: dir/pfx-main-foo.c.*  and\ndir/pfx-main-bar.c.*, respectively.  Contrast with the single-input compilation:\n\ngcc foo.c -c -dumpdir dir/pfx- -dumpbase main ...\n\nthat, applying -dumpbase to a single source, does  not  compute  and  append  a  separate\ndumpbase per input file.  Its auxiliary and dump outputs go in dir/pfx-main.*.\n\nWhen  compiling  and  then  linking  from multiple input files, a defaulted or explicitly\nspecified dumppfx also undergoes the dumpbase- transformation above (e.g. the compilation\nof foo.c and bar.c above, but without -c).  If neither -dumpdir nor -dumpbase are  given,\nthe  linker  output  base  name, minus auxdropsuf, if specified, or the executable suffix\notherwise, plus a dash is appended to the default dumppfx instead.  Note,  however,  that\nunlike earlier cases of linking:\n\ngcc foo.c bar.c -dumpdir dir/pfx- -o main ...\n\ndoes  not  append  the  output  name  main  to  dumppfx,  because  -dumpdir is explicitly\nspecified.  The goal is that the explicitly-specified dumppfx may contain  the  specified\noutput  name  as  part  of the prefix, if desired; only an explicitly-specified -dumpbase\nwould be combined with it, in order to avoid simply discarding a meaningful option.\n\nWhen compiling and then linking from a single input file, the  linker  output  base  name\nwill  only be appended to the default dumppfx as above if it does not share the base name\nwith the single input file name.  This has been covered  in  single-input  linking  cases\nabove,  but  not  with  an  explicit  -dumpdir  that  inhibits  the  combination, even if\noverridden by -save-temps=*:\n\ngcc foo.c -dumpdir alt/pfx- -o dir/main.exe -save-temps=cwd ...\n\nAuxiliary outputs are named foo.*, and dump  outputs  foo.c.*,  in  the  current  working\ndirectory as ultimately requested by -save-temps=cwd.\n\nSumming  it  all  up  for  an  intuitive though slightly imprecise data flow: the primary\noutput name is broken into a directory part and a basename part; dumppfx is  set  to  the\nformer,  unless  overridden  by  -dumpdir  or  -save-temps=*,  and dumpbase is set to the\nlatter, unless overriden by -dumpbase.  If there are multiple  inputs  or  linking,  this\ndumpbase  may  be combined with dumppfx and taken from each input file.  Auxiliary output\nnames for each input are formed by combining dumppfx,  dumpbase  minus  suffix,  and  the\nauxiliary  output  suffix;  dump  output names are only different in that the suffix from\ndumpbase is retained.\n\nWhen it comes  to  auxiliary  and  dump  outputs  created  during  LTO  recompilation,  a\ncombination  of  dumppfx and dumpbase, as given or as derived from the linker output name\nbut not from inputs, even in cases in which this combination would not otherwise be  used\nas such, is passed down with a trailing period replacing the compiler-added dash, if any,\nas  a  -dumpdir  option  to lto-wrapper; being involved in linking, this program does not\nnormally get any -dumpbase and -dumpbase-ext, and it ignores them.\n\nWhen running sub-compilers, lto-wrapper appends LTO stage names to the received  dumppfx,\nensures  it  contains a directory component so that it overrides any -dumpdir, and passes\nthat as -dumpbase to sub-compilers.\n"
                },
                {
                    "name": "-v",
                    "content": "Also  print the version number of the compiler driver program and of the preprocessor and\nthe compiler proper.\n",
                    "flag": "-v"
                },
                {
                    "name": "-###",
                    "content": "Like -v except the commands are not executed and arguments are quoted unless they contain\nonly alphanumeric characters or \"./-\".  This is useful for shell scripts to capture  the\ndriver-generated command lines.\n"
                },
                {
                    "name": "--help",
                    "content": "Print  (on  the  standard output) a description of the command-line options understood by\ngcc.  If the -v option is also specified then --help is also passed  on  to  the  various\nprocesses  invoked by gcc, so that they can display the command-line options they accept.\nIf the -Wextra option has also been specified (prior to the --help option), then command-\nline options that have no documentation associated with them are also displayed.\n",
                    "long": "--help"
                },
                {
                    "name": "--target-help",
                    "content": "Print (on the standard output) a description of target-specific command-line options  for\neach tool.  For some targets extra target-specific information may also be printed.\n\n--help={class|[^]qualifier}[,...]\nPrint  (on  the  standard output) a description of the command-line options understood by\nthe compiler that fit into all specified classes and qualifiers.  These are the supported\nclasses:\n\noptimizers\nDisplay all of the optimization options supported by the compiler.\n\nwarnings\nDisplay all of the options controlling warning messages produced by the compiler.\n\ntarget\nDisplay target-specific options.  Unlike the --target-help  option  however,  target-\nspecific  options  of  the  linker  and assembler are not displayed.  This is because\nthose tools do not currently support the extended --help= syntax.\n\nparams\nDisplay the values recognized by the --param option.\n\nlanguage\nDisplay the options supported for language, where language is the name of one of  the\nlanguages  supported  in  this  version  of  GCC.   If  an option is supported by all\nlanguages, one needs to select common class.\n\ncommon\nDisplay the options that are common to all languages.\n\nThese are the supported qualifiers:\n\nundocumented\nDisplay only those options that are undocumented.\n\njoined\nDisplay options taking an argument that appears after  an  equal  sign  in  the  same\ncontinuous piece of text, such as: --help=target.\n\nseparate\nDisplay  options  taking  an  argument  that appears as a separate word following the\noriginal option, such as: -o output-file.\n\nThus for example to display all the undocumented target-specific  switches  supported  by\nthe compiler, use:\n\n--help=target,undocumented\n\nThe  sense  of  a  qualifier can be inverted by prefixing it with the ^ character, so for\nexample to display all binary warning options (i.e., ones that are either on or  off  and\nthat do not take an argument) that have a description, use:\n\n--help=warnings,^joined,^undocumented\n\nThe argument to --help= should not consist solely of inverted qualifiers.\n\nCombining several classes is possible, although this usually restricts the output so much\nthat  there  is nothing to display.  One case where it does work, however, is when one of\nthe classes is target.  For example, to  display  all  the  target-specific  optimization\noptions, use:\n\n--help=target,optimizers\n\nThe --help= option can be repeated on the command line.  Each successive use displays its\nrequested  class  of options, skipping those that have already been displayed.  If --help\nis also specified anywhere on the command  line  then  this  takes  precedence  over  any\n--help= option.\n\nIf  the  -Q  option  appears  on  the  command  line  before the --help= option, then the\ndescriptive text displayed by --help= is changed.  Instead of  describing  the  displayed\noptions, an indication is given as to whether the option is enabled, disabled or set to a\nspecific  value  (assuming  that  the  compiler knows this at the point where the --help=\noption is used).\n\nHere is a truncated example from the ARM port of gcc:\n\n% gcc -Q -mabi=2 --help=target -c\nThe following options are target specific:\n-mabi=                                2\n-mabort-on-noreturn                   [disabled]\n-mapcs                                [disabled]\n\nThe output is sensitive to the effects of previous command-line options, so  for  example\nit is possible to find out which optimizations are enabled at -O2 by using:\n\n-Q -O2 --help=optimizers\n\nAlternatively you can discover which binary optimizations are enabled by -O3 by using:\n\ngcc -c -Q -O3 --help=optimizers > /tmp/O3-opts\ngcc -c -Q -O2 --help=optimizers > /tmp/O2-opts\ndiff /tmp/O2-opts /tmp/O3-opts | grep enabled\n",
                    "long": "--target-help"
                },
                {
                    "name": "--version",
                    "content": "Display the version number and copyrights of the invoked GCC.\n",
                    "long": "--version"
                },
                {
                    "name": "-pass-exit-codes",
                    "content": "Normally  the gcc program exits with the code of 1 if any phase of the compiler returns a\nnon-success return code.  If  you  specify  -pass-exit-codes,  the  gcc  program  instead\nreturns  with  the  numerically  highest  error  produced by any phase returning an error\nindication.  The C, C++, and Fortran front ends return 4 if an internal compiler error is\nencountered.\n"
                },
                {
                    "name": "-pipe",
                    "content": "Use pipes rather than temporary files for communication between  the  various  stages  of\ncompilation.   This  fails  to work on some systems where the assembler is unable to read\nfrom a pipe; but the GNU assembler has no trouble.\n"
                },
                {
                    "name": "-specs=_",
                    "content": "Process file after the compiler reads in the standard specs file, in  order  to  override\nthe  defaults which the gcc driver program uses when determining what switches to pass to\ncc1, cc1plus, as, ld, etc.  More than one -specs=file can be  specified  on  the  command\nline, and they are processed in order, from left to right.\n"
                },
                {
                    "name": "-wrapper",
                    "content": "Invoke  all subcommands under a wrapper program.  The name of the wrapper program and its\nparameters are passed as a comma separated list.\n\ngcc -c t.c -wrapper gdb,--args\n\nThis invokes all subprograms of gcc under gdb --args, thus the invocation of cc1  is  gdb\n--args cc1 ....\n"
                },
                {
                    "name": "-ffile-prefix-map=_",
                    "content": "When  compiling  files  residing  in  directory old, record any references to them in the\nresult of the compilation as if the files resided in directory new  instead.   Specifying\nthis  option is equivalent to specifying all the individual -f*-prefix-map options.  This\ncan be used to make reproducible  builds  that  are  location  independent.   Directories\nreferenced by directives are not affected by these options.  See also -fmacro-prefix-map,\n-fdebug-prefix-map, -fprofile-prefix-map and -fcanon-prefix-map.\n"
                },
                {
                    "name": "-fcanon-prefix-map",
                    "content": "For  the  -f*-prefix-map  options  normally comparison of old prefix against the filename\nthat would be normally referenced in the result of the compilation is done using  textual\ncomparison  of  the prefixes, or ignoring character case for case insensitive filesystems\nand considering  slashes  and  backslashes  as  equal  on  DOS  based  filesystems.   The\n-fcanon-prefix-map  causes  such comparisons to be done on canonicalized paths of old and\nthe referenced filename.\n"
                },
                {
                    "name": "-fplugin=_",
                    "content": "Load the plugin code in file name.so, assumed to be a shared object to be dlopen'd by the\ncompiler.  The base name of the shared object file is used to identify the plugin for the\npurposes of argument parsing (See -fplugin-arg-name-key=value below).  Each plugin should\ndefine the callback functions specified in the Plugins API.\n"
                },
                {
                    "name": "-fplugin-arg-_ -_",
                    "content": "Define an argument called key with a value of value for the plugin called name.\n"
                },
                {
                    "name": "-fdump-ada-spec -slim",
                    "content": "For C and C++ source and include files, generate corresponding Ada specs.\n"
                },
                {
                    "name": "-fada-spec-parent=_",
                    "content": "In conjunction with -fdump-ada-spec[-slim] above, generate Ada specs as  child  units  of\nparent unit.\n"
                },
                {
                    "name": "-fdump-go-spec=_",
                    "content": "For  input  files  in any language, generate corresponding Go declarations in file.  This\ngenerates Go \"const\", \"type\", \"var\", and \"func\" declarations which may be a useful way to\nstart writing a Go interface to code written in some other language.\n\n@file\nRead command-line options from file.  The options read  are  inserted  in  place  of  the\noriginal  @file  option.  If file does not exist, or cannot be read, then the option will\nbe treated literally, and not removed.\n\nOptions in file are separated by whitespace.  A whitespace character may be  included  in\nan  option  by  surrounding  the  entire  option  in either single or double quotes.  Any\ncharacter (including a backslash) may be  included  by  prefixing  the  character  to  be\nincluded  with  a  backslash.   The file may itself contain additional @file options; any\nsuch options will be processed recursively.\n"
                },
                {
                    "name": "Compiling C++ Programs",
                    "content": "C++ source files conventionally use one of the suffixes .C, .cc, .cpp, .CPP,  .c++,  .cp,  or\n.cxx;  C++  header  files  often  use  .hh, .hpp, .H, or (for shared template code) .tcc; and\npreprocessed C++ files use the suffix  .ii.   GCC  recognizes  files  with  these  names  and\ncompiles  them  as C++ programs even if you call the compiler the same way as for compiling C\nprograms (usually with the name gcc).\n\nHowever, the use of gcc does not add the C++ library.  g++ is a program that  calls  GCC  and\nautomatically  specifies  linking  against the C++ library.  It treats .c, .h and .i files as\nC++ source files instead of C source files unless -x is used.  This program  is  also  useful\nwhen  precompiling  a C header file with a .h extension for use in C++ compilations.  On many\nsystems, g++ is also installed with the name c++.\n\nWhen you compile C++ programs, you may specify many of the same command-line options that you\nuse for compiling programs in any language; or command-line  options  meaningful  for  C  and\nrelated languages; or options that are meaningful only for C++ programs.\n"
                },
                {
                    "name": "Options Controlling C Dialect",
                    "content": "The  following  options  control  the dialect of C (or languages derived from C, such as C++,\nObjective-C and Objective-C++) that the compiler accepts:\n"
                },
                {
                    "name": "-ansi",
                    "content": "In C mode, this is equivalent to -std=c90. In C++ mode, it is equivalent to -std=c++98.\n\nThis turns off certain features of GCC that are incompatible with ISO C90 (when compiling\nC code), or of standard C++ (when compiling C++ code), such as  the  \"asm\"  and  \"typeof\"\nkeywords, and predefined macros such as \"unix\" and \"vax\" that identify the type of system\nyou  are  using.   It  also enables the undesirable and rarely used ISO trigraph feature.\nFor the C compiler, it disables recognition of C++ style  //  comments  as  well  as  the\n\"inline\" keyword.\n\nThe alternate keywords \"asm\", \"extension\", \"inline\" and \"typeof\" continue\nto  work  despite  -ansi.  You would not want to use them in an ISO C program, of course,\nbut it is useful to put them in header files that might be included in compilations  done\nwith  -ansi.   Alternate  predefined  macros  such  as  \"unix\" and \"vax\" are also\navailable, with or without -ansi.\n\nThe -ansi option does not cause non-ISO programs to be rejected gratuitously.  For  that,\n-Wpedantic is required in addition to -ansi.\n\nThe  macro  \"STRICTANSI\"  is  predefined when the -ansi option is used.  Some header\nfiles may notice this macro and refrain from  declaring  certain  functions  or  defining\ncertain  macros that the ISO standard doesn't call for; this is to avoid interfering with\nany programs that might use these names for other things.\n\nFunctions that are normally built in but do not have semantics defined by ISO C (such  as\n\"alloca\" and \"ffs\") are not built-in functions when -ansi is used.\n"
                },
                {
                    "name": "-std=",
                    "content": "Determine the language standard.   This option is currently only supported when compiling\nC or C++.\n\nThe compiler can accept several base standards, such as c90 or c++98, and GNU dialects of\nthose  standards,  such  as  gnu90  or  gnu++98.   When a base standard is specified, the\ncompiler accepts all programs following that standard plus  those  using  GNU  extensions\nthat  do not contradict it.  For example, -std=c90 turns off certain features of GCC that\nare incompatible with ISO C90, such as the \"asm\" and \"typeof\" keywords, but not other GNU\nextensions that do not have a meaning in ISO C90, such as omitting the middle term  of  a\n\"?:\"  expression.  On  the other hand, when a GNU dialect of a standard is specified, all\nfeatures supported by the compiler are enabled,  even  when  those  features  change  the\nmeaning  of  the  base  standard.   As  a  result, some strict-conforming programs may be\nrejected.  The particular standard is used by -Wpedantic to identify which  features  are\nGNU  extensions  given  that  version  of the standard. For example -std=gnu90 -Wpedantic\nwarns about C++ style // comments, while -std=gnu99 -Wpedantic does not.\n\nA value for this option must be provided; possible values are\n\nc90\nc89\niso9899:1990\nSupport all ISO C90 programs (certain GNU extensions that conflict with ISO  C90  are\ndisabled). Same as -ansi for C code.\n\niso9899:199409\nISO C90 as modified in amendment 1.\n\nc99\nc9x\niso9899:1999\niso9899:199x\nISO  C99.   This  standard  is  substantially  completely  supported, modulo bugs and\nfloating-point issues (mainly but not entirely relating to optional C99 features from\nAnnexes F and G).  See  <https://gcc.gnu.org/c99status.html>  for  more  information.\nThe names c9x and iso9899:199x are deprecated.\n\nc11\nc1x\niso9899:2011\nISO  C11,  the  2011  revision of the ISO C standard.  This standard is substantially\ncompletely supported, modulo bugs, floating-point issues  (mainly  but  not  entirely\nrelating  to  optional  C11 features from Annexes F and G) and the optional Annexes K\n(Bounds-checking interfaces) and L (Analyzability).  The name c1x is deprecated.\n\nc17\nc18\niso9899:2017\niso9899:2018\nISO C17, the 2017 revision of the ISO C standard (published in 2018).  This  standard\nis  same as C11 except for corrections of defects (all of which are also applied with\n-std=c11) and a new value of \"STDCVERSION\", and so  is  supported  to  the  same\nextent as C11.\n\nc2x The  next  version  of  the ISO C standard, still under development.  The support for\nthis version is experimental and incomplete.\n\ngnu90\ngnu89\nGNU dialect of ISO C90 (including some C99 features).\n\ngnu99\ngnu9x\nGNU dialect of ISO C99.  The name gnu9x is deprecated.\n\ngnu11\ngnu1x\nGNU dialect of ISO C11.  The name gnu1x is deprecated.\n\ngnu17\ngnu18\nGNU dialect of ISO C17.  This is the default for C code.\n\ngnu2x\nThe next version of the ISO C standard, still under development, plus GNU extensions.\nThe support for this version is experimental and incomplete.\n\nc++98\nc++03\nThe 1998 ISO C++ standard plus the 2003 technical  corrigendum  and  some  additional\ndefect reports. Same as -ansi for C++ code.\n\ngnu++98\ngnu++03\nGNU dialect of -std=c++98.\n\nc++11\nc++0x\nThe 2011 ISO C++ standard plus amendments.  The name c++0x is deprecated.\n\ngnu++11\ngnu++0x\nGNU dialect of -std=c++11.  The name gnu++0x is deprecated.\n\nc++14\nc++1y\nThe 2014 ISO C++ standard plus amendments.  The name c++1y is deprecated.\n\ngnu++14\ngnu++1y\nGNU dialect of -std=c++14.  The name gnu++1y is deprecated.\n\nc++17\nc++1z\nThe 2017 ISO C++ standard plus amendments.  The name c++1z is deprecated.\n\ngnu++17\ngnu++1z\nGNU  dialect  of  -std=c++17.  This is the default for C++ code.  The name gnu++1z is\ndeprecated.\n\nc++20\nc++2a\nThe 2020 ISO C++ standard plus amendments.  Support is experimental, and could change\nin incompatible ways in future releases.  The name c++2a is deprecated.\n\ngnu++20\ngnu++2a\nGNU dialect of -std=c++20.  Support is experimental, and could change in incompatible\nways in future releases.  The name gnu++2a is deprecated.\n\nc++2b\nc++23\nThe next revision of the ISO C++ standard,  planned  for  2023.   Support  is  highly\nexperimental,  and  will  almost  certainly  change  in  incompatible  ways in future\nreleases.\n\ngnu++2b\ngnu++23\nGNU dialect of -std=c++2b.  Support is highly experimental, and will almost certainly\nchange in incompatible ways in future releases.\n"
                },
                {
                    "name": "-aux-info _",
                    "content": "Output to the given filename prototyped declarations for all  functions  declared  and/or\ndefined  in a translation unit, including those in header files.  This option is silently\nignored in any language other than C.\n\nBesides declarations, the file indicates, in comments, the  origin  of  each  declaration\n(source  file and line), whether the declaration was implicit, prototyped or unprototyped\n(I, N for new or O for old, respectively, in the first character after  the  line  number\nand  the  colon),  and  whether  it  came  from  a  declaration  or a definition (C or F,\nrespectively, in the following character).   In  the  case  of  function  definitions,  a\nK&R-style  list  of  arguments  followed  by  their declarations is also provided, inside\ncomments, after the declaration.\n"
                },
                {
                    "name": "-fno-asm",
                    "content": "Do not recognize \"asm\", \"inline\" or \"typeof\" as a keyword, so that  code  can  use  these\nwords  as identifiers.  You can use the keywords \"asm\", \"inline\" and \"typeof\"\ninstead.  In C, -ansi implies -fno-asm.\n\nIn C++, \"inline\" is a standard keyword and is not affected by this switch.  You may  want\nto  use  the  -fno-gnu-keywords  flag  instead, which disables \"typeof\" but not \"asm\" and\n\"inline\".  In C99 mode (-std=c99 or -std=gnu99), this switch only affects the  \"asm\"  and\n\"typeof\"  keywords,  since  \"inline\"  is  a  standard  keyword  in  ISO C99.  In C2X mode\n(-std=c2x or -std=gnu2x), this switch only affects the \"asm\" keyword, since \"typeof\" is a\nstandard keyword in ISO C2X.\n"
                },
                {
                    "name": "-fno-builtin",
                    "content": ""
                },
                {
                    "name": "-fno-builtin-_",
                    "content": "Don't recognize built-in functions that do not begin with builtin as prefix.\n\nGCC  normally  generates  special  code  to  handle  certain  built-in   functions   more\nefficiently;  for instance, calls to \"alloca\" may become single instructions which adjust\nthe stack directly, and calls to \"memcpy\" may become inline copy  loops.   The  resulting\ncode  is  often both smaller and faster, but since the function calls no longer appear as\nsuch, you cannot set a breakpoint on those calls, nor can you change the behavior of  the\nfunctions  by  linking  with  a  different  library.   In  addition,  when  a function is\nrecognized as a built-in function, GCC may use information about that  function  to  warn\nabout  problems  with calls to that function, or to generate more efficient code, even if\nthe resulting code still contains calls to that  function.   For  example,  warnings  are\ngiven  with  -Wformat for bad calls to \"printf\" when \"printf\" is built in and \"strlen\" is\nknown not to modify global memory.\n\nWith the -fno-builtin-function option only the built-in function  function  is  disabled.\nfunction  must not begin with builtin.  If a function is named that is not built-in in\nthis  version  of  GCC,  this   option   is   ignored.    There   is   no   corresponding\n-fbuiltin-function  option;  if  you  wish  to enable built-in functions selectively when\nusing -fno-builtin or -ffreestanding, you may define macros such as:\n\n#define abs(n)          builtinabs ((n))\n#define strcpy(d, s)    builtinstrcpy ((d), (s))\n"
                },
                {
                    "name": "-fcond-mismatch",
                    "content": "Allow conditional expressions with mismatched types in the second  and  third  arguments.\nThe value of such an expression is void.  This option is not supported for C++.\n"
                },
                {
                    "name": "-ffreestanding",
                    "content": "Assert  that  compilation targets a freestanding environment.  This implies -fno-builtin.\nA freestanding environment is one in which  the  standard  library  may  not  exist,  and\nprogram  startup  may  not  necessarily  be at \"main\".  The most obvious example is an OS\nkernel.  This is equivalent to -fno-hosted.\n"
                },
                {
                    "name": "-fgimple",
                    "content": "Enable parsing of function definitions marked with \"GIMPLE\".  This is  an  experimental\nfeature that allows unit testing of GIMPLE passes.\n"
                },
                {
                    "name": "-fgnu-tm",
                    "content": "When  the option -fgnu-tm is specified, the compiler generates code for the Linux variant\nof Intel's current Transactional Memory ABI specification document (Revision 1.1,  May  6\n2009).   This is an experimental feature whose interface may change in future versions of\nGCC, as the official specification changes.  Please note that not all  architectures  are\nsupported for this feature.\n\nFor more information on GCC's support for transactional memory,\n\nNote  that  the  transactional  memory  feature is not supported with non-call exceptions\n(-fnon-call-exceptions).\n"
                },
                {
                    "name": "-fgnu89-inline",
                    "content": "The option -fgnu89-inline tells GCC to use the traditional  GNU  semantics  for  \"inline\"\nfunctions when in C99 mode.\n\nUsing  this option is roughly equivalent to adding the \"gnuinline\" function attribute to\nall inline functions.\n\nThe option -fno-gnu89-inline explicitly tells GCC to use the C99 semantics  for  \"inline\"\nwhen  in C99 or gnu99 mode (i.e., it specifies the default behavior).  This option is not\nsupported in -std=c90 or -std=gnu90 mode.\n\nThe preprocessor macros \"GNUCGNUINLINE\" and \"GNUCSTDCINLINE\" may be  used  to\ncheck which semantics are in effect for \"inline\" functions.\n"
                },
                {
                    "name": "-fhosted",
                    "content": "Assert  that compilation targets a hosted environment.  This implies -fbuiltin.  A hosted\nenvironment is one in which the entire standard library is available, and in which \"main\"\nhas a return type of \"int\".  Examples are nearly everything except  a  kernel.   This  is\nequivalent to -fno-freestanding.\n"
                },
                {
                    "name": "-flax-vector-conversions",
                    "content": "Allow  implicit  conversions  between  vectors  with differing numbers of elements and/or\nincompatible element types.  This option should not be used for new code.\n"
                },
                {
                    "name": "-fms-extensions",
                    "content": "Accept some non-standard constructs used in Microsoft header files.\n\nIn C++ code, this allows member names in structures  to  be  similar  to  previous  types\ndeclarations.\n\ntypedef int UOW;\nstruct ABC {\nUOW UOW;\n};\n\nSome cases of unnamed fields in structures and unions are only accepted with this option.\n\nNote that this option is off for all targets except for x86 targets using ms-abi.\n"
                },
                {
                    "name": "-foffload=disable",
                    "content": ""
                },
                {
                    "name": "-foffload=default",
                    "content": ""
                },
                {
                    "name": "-foffload=_",
                    "content": "Specify  for  which  OpenMP  and  OpenACC  offload targets code should be generated.  The\ndefault behavior, equivalent to -foffload=default, is to generate code for all  supported\noffload  targets.   The -foffload=disable form generates code only for the host fallback,\nwhile -foffload=target-list generates code only for the specified comma-separated list of\noffload targets.\n\nOffload targets are specified in GCC's internal target-triplet format. You  can  run  the\ncompiler   with   -v   to   show   the   list   of   configured   offload  targets  under\n\"OFFLOADTARGETNAMES\".\n"
                },
                {
                    "name": "-foffload-options=_",
                    "content": ""
                },
                {
                    "name": "-foffload-options=_",
                    "content": "With -foffload-options=options, GCC passes the specified options to the compilers for all\nenabled offloading targets.  You can specify options that apply only to a specific target\nor targets by using the -foffload-options=target-list=options form.  The target-list is a\ncomma-separated list in the same format as for the -foffload= option.\n\nTypical command lines are\n\n-foffload-options=-lgfortran -foffload-options=-lm\n-foffload-options=\"-lgfortran -lm\" -foffload-options=nvptx-none=-latomic\n-foffload-options=amdgcn-amdhsa=-march=gfx906 -foffload-options=-lm\n"
                },
                {
                    "name": "-fopenacc",
                    "content": "Enable handling of OpenACC directives \"#pragma acc\" in  C/C++  and  \"!$acc\"  in  Fortran.\nWhen  -fopenacc  is  specified,  the compiler generates accelerated code according to the\nOpenACC Application Programming Interface v2.6  <https://www.openacc.org>.   This  option\nimplies -pthread, and thus is only supported on targets that have support for -pthread.\n"
                },
                {
                    "name": "-fopenacc-dim=_",
                    "content": "Specify  default  compute  dimensions for parallel offload regions that do not explicitly\nspecify.  The geom value is a triple of ':'-separated sizes, in  order  'gang',  'worker'\nand, 'vector'.  A size can be omitted, to use a target-specific default value.\n"
                },
                {
                    "name": "-fopenmp",
                    "content": "Enable  handling  of  OpenMP directives \"#pragma omp\" in C/C++, \"[[omp::directive(...)]]\"\nand \"[[omp::sequence(...)]]\" in C++ and \"!$omp\" in Fortran.  When -fopenmp is  specified,\nthe  compiler  generates  parallel  code  according  to  the  OpenMP  Application Program\nInterface v4.5 <https://www.openmp.org>.  This option implies -pthread, and thus is  only\nsupported on targets that have support for -pthread. -fopenmp implies -fopenmp-simd.\n"
                },
                {
                    "name": "-fopenmp-simd",
                    "content": "Enable  handling  of  OpenMP's  \"simd\",  \"declare  simd\",  \"declare reduction\", \"assume\",\n\"ordered\", \"scan\", \"loop\" directives and combined or composite directives with \"simd\"  as\nconstituent    with    \"#pragma    omp\"    in    C/C++,   \"[[omp::directive(...)]]\"   and\n\"[[omp::sequence(...)]]\" in C++ and \"!$omp\" in  Fortran.   Other  OpenMP  directives  are\nignored.\n"
                },
                {
                    "name": "-fopenmp-target-simd-clone",
                    "content": ""
                },
                {
                    "name": "-fopenmp-target-simd-clone=_",
                    "content": "In  addition  to  generating  SIMD  clones  for  functions marked with the \"declare simd\"\ndirective, GCC also generates clones  for  functions  marked  with  the  OpenMP  \"declare\ntarget\" directive that are suitable for vectorization when this option is in effect.  The\ndevice-type  may  be  one  of  \"none\",  \"host\",  \"nohost\", and \"any\", which correspond to\nkeywords for the \"devicetype\" clause of  the  \"declare  target\"  directive;  clones  are\ngenerated  for  the  intersection  of  devices  specified.  -fopenmp-target-simd-clone is\nequivalent  to  -fopenmp-target-simd-clone=any   and   -fno-openmp-target-simd-clone   is\nequivalent to -fopenmp-target-simd-clone=none.\n\nAt   -O2   and   higher   (but   not   -Os   or   -Og)   this  optimization  defaults  to\n-fopenmp-target-simd-clone=nohost; otherwise it is disabled by default.\n"
                },
                {
                    "name": "-fpermitted-flt-eval-methods=_",
                    "content": "ISO/IEC TS 18661-3 defines new permissible values  for  \"FLTEVALMETHOD\"  that  indicate\nthat  operations  and  constants  with a semantic type that is an interchange or extended\nformat should be evaluated to the precision and range of that type.  These new values are\na superset of those permitted under C99/C11, which does not specify the meaning of  other\npositive  values of \"FLTEVALMETHOD\".  As such, code conforming to C11 may not have been\nwritten expecting the possibility of the new values.\n\n-fpermitted-flt-eval-methods specifies whether the compiler should allow only the  values\nof  \"FLTEVALMETHOD\"  specified  in  C99/C11, or the extended set of values specified in\nISO/IEC TS 18661-3.\n\nstyle is either \"c11\" or \"ts-18661-3\" as appropriate.\n\nThe  default  when  in  a   standards   compliant   mode   (-std=c11   or   similar)   is\n-fpermitted-flt-eval-methods=c11.   The  default  when  in  a  GNU dialect (-std=gnu11 or\nsimilar) is -fpermitted-flt-eval-methods=ts-18661-3.\n"
                },
                {
                    "name": "-fplan9-extensions",
                    "content": "Accept some non-standard constructs used in Plan 9 code.\n\nThis enables -fms-extensions, permits  passing  pointers  to  structures  with  anonymous\nfields  to  functions  that  expect  pointers  to  elements of the type of the field, and\npermits referring to anonymous fields declared using a typedef.    This is only supported\nfor C, not C++.\n"
                },
                {
                    "name": "-fsigned-bitfields",
                    "content": ""
                },
                {
                    "name": "-funsigned-bitfields",
                    "content": ""
                },
                {
                    "name": "-fno-signed-bitfields",
                    "content": ""
                },
                {
                    "name": "-fno-unsigned-bitfields",
                    "content": "These options control whether a bit-field is signed or  unsigned,  when  the  declaration\ndoes  not  use  either  \"signed\"  or \"unsigned\".  By default, such a bit-field is signed,\nbecause this is consistent: the basic integer types such as \"int\" are signed types.\n"
                },
                {
                    "name": "-fsigned-char",
                    "content": "Let the type \"char\" be signed, like \"signed char\".\n\nNote that this is equivalent  to  -fno-unsigned-char,  which  is  the  negative  form  of\n-funsigned-char.  Likewise, the option -fno-signed-char is equivalent to -funsigned-char.\n"
                },
                {
                    "name": "-funsigned-char",
                    "content": "Let the type \"char\" be unsigned, like \"unsigned char\".\n\nEach  kind  of  machine  has  a  default  for  what  \"char\" should be.  It is either like\n\"unsigned char\" by default or like \"signed char\" by default.\n\nIdeally, a portable program should always use \"signed char\" or \"unsigned  char\"  when  it\ndepends on the signedness of an object.  But many programs have been written to use plain\n\"char\" and expect it to be signed, or expect it to be unsigned, depending on the machines\nthey  were  written  for.  This option, and its inverse, let you make such a program work\nwith the opposite default.\n\nThe type \"char\" is always a distinct type from each of \"signed char\" or \"unsigned  char\",\neven though its behavior is always just like one of those two.\n"
                },
                {
                    "name": "-fstrict-flex-arrays",
                    "content": "Control  when  to  treat the trailing array of a structure as a flexible array member for\nthe purpose of accessing the elements of such an array.  The positive form is  equivalent\nto  -fstrict-flex-arrays=3,  which  is  the  strictest.  A trailing array is treated as a\nflexible array member only when it is  declared  as  a  flexible  array  member  per  C99\nstandard  onwards.   The  negative form is equivalent to -fstrict-flex-arrays=0, which is\nthe least strict.  All trailing arrays  of  structures  are  treated  as  flexible  array\nmembers.\n"
                },
                {
                    "name": "-fstrict-flex-arrays=_",
                    "content": "Control  when  to  treat the trailing array of a structure as a flexible array member for\nthe purpose of accessing the elements of such an array.  The value of level controls  the\nlevel of strictness.\n\nThe possible values of level are the same as for the \"strictflexarray\" attribute.\n\nYou can control this behavior for a specific trailing array field of a structure by using\nthe variable attribute \"strictflexarray\" attribute.\n"
                },
                {
                    "name": "-fsso-struct=_",
                    "content": "Set  the  default  scalar  storage  order  of  structures  and  unions  to  the specified\nendianness.  The accepted values are big-endian, little-endian and native for the  native\nendianness of the target (the default).  This option is not supported for C++.\n\nWarning:  the  -fsso-struct  switch  causes  GCC  to  generate  code  that  is not binary\ncompatible with code generated without it if the specified endianness is not  the  native\nendianness of the target.\n"
                },
                {
                    "name": "Options Controlling C++ Dialect",
                    "content": "This  section  describes  the command-line options that are only meaningful for C++ programs.\nYou can also use most of the GNU compiler options regardless of what language your program is\nin.  For example, you might compile a file firstClass.C like this:\n\ng++ -g -fstrict-enums -O -c firstClass.C\n\nIn this example, only -fstrict-enums is an option meant only for C++ programs;  you  can  use\nthe other options with any language supported by GCC.\n\nSome options for compiling C programs, such as -std, are also relevant for C++ programs.\n\nHere is a list of options that are only for compiling C++ programs:\n"
                },
                {
                    "name": "-fabi-version=_",
                    "content": "Use version n of the C++ ABI.  The default is version 0.\n\nVersion  0  refers  to  the version conforming most closely to the C++ ABI specification.\nTherefore, the ABI obtained using version 0 will change in different versions of  G++  as\nABI bugs are fixed.\n\nVersion 1 is the version of the C++ ABI that first appeared in G++ 3.2.\n\nVersion  2  is  the  version  of  the C++ ABI that first appeared in G++ 3.4, and was the\ndefault through G++ 4.9.\n\nVersion 3 corrects an error in mangling a constant address as a template argument.\n\nVersion 4, which first appeared in G++ 4.5, implements a  standard  mangling  for  vector\ntypes.\n\nVersion  5,  which  first  appeared  in  G++  4.6,  corrects  the  mangling  of attribute\nconst/volatile on function pointer types, decltype of a plain decl, and use of a function\nparameter in the declaration of another parameter.\n\nVersion 6, which first appeared in G++ 4.7, corrects  the  promotion  behavior  of  C++11\nscoped  enums  and  the mangling of template argument packs, const/staticcast, prefix ++\nand --, and a class scope function used as a template argument.\n\nVersion 7, which first appeared in G++ 4.8, that treats nullptrt as a builtin  type  and\ncorrects the mangling of lambdas in default argument scope.\n\nVersion  8,  which  first  appeared  in  G++  4.9,  corrects the substitution behavior of\nfunction types with function-cv-qualifiers.\n\nVersion 9, which first appeared in G++ 5.2, corrects the alignment of \"nullptrt\".\n\nVersion 10, which first appeared in G++ 6.1, adds mangling of attributes that affect type\nidentity, such as ia32 calling convention attributes (e.g. stdcall).\n\nVersion 11, which first appeared in G++ 7, corrects the mangling of sizeof... expressions\nand operator names.  For multiple entities with the same name within a function, that are\ndeclared in different  scopes,  the  mangling  now  changes  starting  with  the  twelfth\noccurrence.  It also implies -fnew-inheriting-ctors.\n\nVersion  12,  which  first  appeared in G++ 8, corrects the calling conventions for empty\nclasses on the x8664 target and for classes with only  deleted  copy/move  constructors.\nIt  accidentally  changes  the  calling  convention  for  classes  with  a  deleted  copy\nconstructor and a trivial move constructor.\n\nVersion 13, which first appeared in G++ 8.2, fixes the accidental change in version 12.\n\nVersion 14, which first appeared  in  G++  10,  corrects  the  mangling  of  the  nullptr\nexpression.\n\nVersion 15, which first appeared in G++ 10.3, corrects G++ 10 ABI tag regression.\n\nVersion  16,  which first appeared in G++ 11, changes the mangling of \"alignof\" to be\ndistinct from that of \"alignof\", and dependent operator names.\n\nVersion 17, which first appeared in G++ 12, fixes layout of  classes  that  inherit  from\naggregate classes with default member initializers in C++14 and up.\n\nVersion  18,  which  first  appeard  in  G++  13,  fixes  manglings  of lambdas that have\nadditional context.\n\nSee also -Wabi.\n"
                },
                {
                    "name": "-fabi-compat-version=_",
                    "content": "On targets that support strong aliases, G++ works around mangling changes by creating  an\nalias  with  the  correct  mangled  name when defining a symbol with an incorrect mangled\nname.  This switch specifies which ABI version to use for the alias.\n\nWith -fabi-version=0 (the default), this defaults to  13  (GCC  8.2  compatibility).   If\nanother  ABI  version is explicitly selected, this defaults to 0.  For compatibility with\nGCC versions 3.2 through 4.9, use -fabi-compat-version=2.\n\nIf this option is not provided but -Wabi=n is, that version  is  used  for  compatibility\naliases.   If this option is provided along with -Wabi (without the version), the version\nfrom this option is used for the warning.\n"
                },
                {
                    "name": "-fno-access-control",
                    "content": "Turn off all access checking.  This switch is mainly useful for working  around  bugs  in\nthe access control code.\n"
                },
                {
                    "name": "-faligned-new",
                    "content": "Enable  support  for  C++17  \"new\"  of  types  that  require  more  alignment than \"void*\n::operator new(std::sizet)\" provides.  A numeric argument such as \"-faligned-new=32\" can\nbe used to specify how much alignment (in bytes) is provided by that  function,  but  few\nusers will need to override the default of alignof(std::maxalignt).\n\nThis flag is enabled by default for -std=c++17.\n"
                },
                {
                    "name": "-fchar8_t",
                    "content": ""
                },
                {
                    "name": "-fno-char8_t",
                    "content": "Enable  support  for \"char8t\" as adopted for C++20.  This includes the addition of a new\n\"char8t\" fundamental type, changes to the types of UTF-8 string and character  literals,\nnew  signatures  for  user-defined literals, associated standard library updates, and new\n\"cppchar8t\" and \"cpplibchar8t\" feature test macros.\n\nThis option enables functions to be overloaded for ordinary and UTF-8 strings:\n\nint f(const char *);    // #1\nint f(const char8t *); // #2\nint v1 = f(\"text\");     // Calls #1\nint v2 = f(u8\"text\");   // Calls #2\n\nand introduces new signatures for user-defined literals:\n\nint operator\"\"udl1(char8t);\nint v3 = u8'x'udl1;\nint operator\"\"udl2(const char8t*, std::sizet);\nint v4 = u8\"text\"udl2;\ntemplate<typename T, T...> int operator\"\"udl3();\nint v5 = u8\"text\"udl3;\n\nThe  change  to  the  types  of  UTF-8   string   and   character   literals   introduces\nincompatibilities with ISO C++11 and later standards.  For example, the following code is\nwell-formed under ISO C++11, but is ill-formed when -fchar8t is specified.\n\nconst char *cp = u8\"xx\";// error: invalid conversion from\n//        `const char8t*' to `const char*'\nint f(const char*);\nauto v = f(u8\"xx\");     // error: invalid conversion from\n//        `const char8t*' to `const char*'\nstd::string s{u8\"xx\"};  // error: no matching function for call to\n//        `std::basicstring<char>::basicstring()'\nusing namespace std::literals;\ns = u8\"xx\"s;            // error: conversion from\n//        `basicstring<char8t>' to non-scalar\n//        type `basicstring<char>' requested\n"
                },
                {
                    "name": "-fcheck-new",
                    "content": "Check that the pointer returned by \"operator new\" is non-null before attempting to modify\nthe  storage  allocated.   This  check  is  normally unnecessary because the C++ standard\nspecifies that \"operator new\" only returns 0 if it is declared throw(), in which case the\ncompiler always checks the return value even without this option.  In  all  other  cases,\nwhen  \"operator  new\"  has  a  non-empty  exception  specification,  memory exhaustion is\nsignalled by throwing \"std::badalloc\".  See also new (nothrow).\n"
                },
                {
                    "name": "-fconcepts",
                    "content": ""
                },
                {
                    "name": "-fconcepts-ts",
                    "content": "Enable support for the C++ Concepts feature for constraining  template  arguments.   With\n-std=c++20  and above, Concepts are part of the language standard, so -fconcepts defaults\nto on.\n\nSome constructs that were allowed by the earlier C++ Extensions  for  Concepts  Technical\nSpecification,  ISO  19217 (2015), but didn't make it into the standard, can additionally\nbe enabled by -fconcepts-ts.\n"
                },
                {
                    "name": "-fconstexpr-depth=_",
                    "content": "Set the maximum nested evaluation depth for C++11 constexpr functions to n.  A  limit  is\nneeded  to  detect  endless recursion during constant expression evaluation.  The minimum\nspecified by the standard is 512.\n"
                },
                {
                    "name": "-fconstexpr-cache-depth=_",
                    "content": "Set the maximum level of nested evaluation depth for C++11 constexpr functions that  will\nbe  cached  to  n.  This is a heuristic that trades off compilation speed (when the cache\navoids repeated calculations) against memory consumption (when the cache grows very large\nfrom highly recursive evaluations).  The default is 8.  Very few users are likely to want\nto adjust it, but if your code does  heavy  constexpr  calculations  you  might  want  to\nexperiment to find which value works best for you.\n"
                },
                {
                    "name": "-fconstexpr-fp-except",
                    "content": "Annex  F of the C standard specifies that IEC559 floating point exceptions encountered at\ncompile time should not stop compilation.  C++ compilers have historically  not  followed\nthis  guidance,  instead  treating  floating  point division by zero as non-constant even\nthough it has a well defined value.  This  flag  tells  the  compiler  to  give  Annex  F\npriority over other rules saying that a particular operation is undefined.\n\nconstexpr float inf = 1./0.; // OK with -fconstexpr-fp-except\n"
                },
                {
                    "name": "-fconstexpr-loop-limit=_",
                    "content": "Set  the  maximum  number  of iterations for a loop in C++14 constexpr functions to n.  A\nlimit is needed to detect infinite loops  during  constant  expression  evaluation.   The\ndefault is 262144 (1<<18).\n"
                },
                {
                    "name": "-fconstexpr-ops-limit=_",
                    "content": "Set  the  maximum  number  of operations during a single constexpr evaluation.  Even when\nnumber of iterations of a single loop is limited with  the  above  limit,  if  there  are\nseveral  nested  loops  and  each  of them has many iterations but still smaller than the\nabove limit, or if in a body of some loop or even outside of a loop too many  expressions\nneed  to  be  evaluated,  the  resulting  constexpr  evaluation might take too long.  The\ndefault is 33554432 (1<<25).\n"
                },
                {
                    "name": "-fcontracts",
                    "content": "Enable experimental support for the C++ Contracts feature, as briefly added to  and  then\nremoved  from the C++20 working paper (N4820).  The implementation also includes proposed\nenhancements from papers P1290, P1332, and P1429.  This functionality is intended  mostly\nfor those interested in experimentation towards refining the feature to get it into shape\nfor a future C++ standard.\n\nOn  violation  of a checked contract, the violation handler is called.  Users can replace\nthe violation handler by defining\n\nvoid\nhandlecontractviolation (const std::experimental::contractviolation&);\n\nThere are different sets of additional flags that can be used together to  specify  which\ncontracts  will  be  checked  and  how,  for  N4820  contracts, P1332 contracts, or P1429\ncontracts; these sets cannot be used together.\n\n-fcontract-mode=[on|off]\nControl whether any contracts have any semantics at all.  Defaults to on.\n\n-fcontract-assumption-mode=[on|off]\n[N4820] Control whether contracts with level axiom should have the  assume  semantic.\nDefaults to on.\n\n-fcontract-build-level=[off|default|audit]\n[N4820]  Specify  which  level  of  contracts  to  generate  checks for.  Defaults to\ndefault.\n\n-fcontract-continuation-mode=[on|off]\n[N4820] Control whether to allow the program to continue executing after  a  contract\nviolation.   That  is,  do  checked contracts have the maybe semantic described below\nrather than the never semantic.  Defaults to off.\n\n-fcontract-role=<name>:<default>,<audit>,<axiom>\n[P1332] Specify the concrete semantics  for  each  contract  level  of  a  particular\ncontract role.\n\n-fcontract-semantic=[default|audit|axiom]:<semantic>\n[P1429] Specify the concrete semantic for a particular contract level.\n\n-fcontract-strict-declarations=[on|off]\nControl whether to reject adding contracts to a function after its first declaration.\nDefaults to off.\n\nThe  possible  concrete  semantics  for  that  can  be  specified with -fcontract-role or\n-fcontract-semantic are:\n\n\"ignore\"\nThis contract has no effect.\n\n\"assume\"\nThis contract is treated like C++23 \"[[assume]]\".\n\n\"checknevercontinue\"\n\"never\"\n\"abort\"\nThis contract is checked.  If it fails, the violation  handler  is  called.   If  the\nhandler returns, \"std::terminate\" is called.\n\n\"checkmaybecontinue\"\n\"maybe\"\nThis  contract  is  checked.   If  it fails, the violation handler is called.  If the\nhandler returns, execution continues normally.\n"
                },
                {
                    "name": "-fcoroutines",
                    "content": "Enable support for the C++ coroutines extension (experimental).\n"
                },
                {
                    "name": "-fno-elide-constructors",
                    "content": "The C++ standard allows an implementation to omit creating a temporary that is only  used\nto  initialize  another  object  of  the same type.  Specifying this option disables that\noptimization, and forces G++ to call the copy constructor in all cases.  This option also\ncauses G++ to call trivial member functions which otherwise would be expanded inline.\n\nIn C++17, the compiler is required to omit  these  temporaries,  but  this  option  still\naffects trivial member functions.\n"
                },
                {
                    "name": "-fno-enforce-eh-specs",
                    "content": "Don't generate code to check for violation of exception specifications at run time.  This\noption  violates the C++ standard, but may be useful for reducing code size in production\nbuilds, much like defining \"NDEBUG\".  This does not give user code  permission  to  throw\nexceptions  in  violation  of  the exception specifications; the compiler still optimizes\nbased on the specifications, so throwing an unexpected  exception  results  in  undefined\nbehavior at run time.\n"
                },
                {
                    "name": "-fextern-tls-init",
                    "content": ""
                },
                {
                    "name": "-fno-extern-tls-init",
                    "content": "The C++11 and OpenMP standards allow \"threadlocal\" and \"threadprivate\" variables to have\ndynamic  (runtime)  initialization.   To  support  this,  any use of such a variable goes\nthrough a wrapper function that performs any necessary initialization.  When the use  and\ndefinition  of  the  variable  are  in  the  same  translation unit, this overhead can be\noptimized away, but when the use is in a different translation unit there is  significant\noverhead  even  if  the  variable  doesn't  actually need dynamic initialization.  If the\nprogrammer can be sure that no use of the variable in a non-defining TU needs to  trigger\ndynamic  initialization  (either because the variable is statically initialized, or a use\nof the variable in the defining TU will be executed before any uses in another TU),  they\ncan avoid this overhead with the -fno-extern-tls-init option.\n\nOn  targets  that  support  symbol aliases, the default is -fextern-tls-init.  On targets\nthat do not support symbol aliases, the default is -fno-extern-tls-init.\n"
                },
                {
                    "name": "-ffold-simple-inlines",
                    "content": ""
                },
                {
                    "name": "-fno-fold-simple-inlines",
                    "content": "Permit the C++ frontend to fold calls to  \"std::move\",  \"std::forward\",  \"std::addressof\"\nand  \"std::asconst\".   In  contrast to inlining, this means no debug information will be\ngenerated for such calls.  Since these functions are rarely interesting  to  debug,  this\nflag is enabled by default unless -fno-inline is active.\n"
                },
                {
                    "name": "-fno-gnu-keywords",
                    "content": "Do  not recognize \"typeof\" as a keyword, so that code can use this word as an identifier.\nYou can use the keyword \"typeof\" instead.  This option is implied by the  strict  ISO\nC++ dialects: -ansi, -std=c++98, -std=c++11, etc.\n"
                },
                {
                    "name": "-fimplicit-constexpr",
                    "content": "Make  inline  functions  implicitly  constexpr,  if  they  satisfy the requirements for a\nconstexpr function.  This option can be used in C++14 mode or later.  This can result  in\ninitialization changing from dynamic to static and other optimizations.\n"
                },
                {
                    "name": "-fno-implicit-templates",
                    "content": "Never  emit code for non-inline templates that are instantiated implicitly (i.e. by use);\nonly emit code for explicit instantiations.  If you use this option, you must  take  care\nto  structure  your  code  to  include all the necessary explicit instantiations to avoid\ngetting undefined symbols at link time.\n"
                },
                {
                    "name": "-fno-implicit-inline-templates",
                    "content": "Don't emit code for implicit instantiations of inline templates, either.  The default  is\nto  handle  inlines  differently  so that compiles with and without optimization need the\nsame set of explicit instantiations.\n"
                },
                {
                    "name": "-fno-implement-inlines",
                    "content": "To save space, do not emit out-of-line copies of inline functions controlled by  \"#pragma\nimplementation\".  This causes linker errors if these functions are not inlined everywhere\nthey are called.\n"
                },
                {
                    "name": "-fmodules-ts",
                    "content": ""
                },
                {
                    "name": "-fno-modules-ts",
                    "content": "Enable  support for C++20 modules.  The -fno-modules-ts is usually not needed, as that is\nthe default.  Even though this is a C++20 feature, it is not currently implicitly enabled\nby selecting that standard version.\n"
                },
                {
                    "name": "-fmodule-header",
                    "content": ""
                },
                {
                    "name": "-fmodule-header=user",
                    "content": ""
                },
                {
                    "name": "-fmodule-header=system",
                    "content": "Compile a header file to create an importable header unit.\n"
                },
                {
                    "name": "-fmodule-implicit-inline",
                    "content": "Member functions defined in their class definitions are not implicitly inline for modular\ncode.  This is different to traditional C++ behavior, for good reasons.  However, it  may\nresult  in a difficulty during code porting.  This option makes such function definitions\nimplicitly inline.  It does however generate an ABI incompatibility, so you must  use  it\neverywhere  or  nowhere.   (Such  definitions outside of a named module remain implicitly\ninline, regardless.)\n"
                },
                {
                    "name": "-fno-module-lazy",
                    "content": "Disable lazy module importing and module mapper creation.\n"
                },
                {
                    "name": "-fmodule-mapper=",
                    "content": ""
                },
                {
                    "name": "-fmodule-mapper=|_",
                    "content": ""
                },
                {
                    "name": "-fmodule-mapper==_",
                    "content": ""
                },
                {
                    "name": "-fmodule-mapper=<>",
                    "content": ""
                },
                {
                    "name": "-fmodule-mapper=<_",
                    "content": ""
                },
                {
                    "name": "-fmodule-mapper=_",
                    "content": "An  oracle  to  query  for  module  name  to  filename  mappings.   If  unspecified   the\nCXXMODULEMAPPER  environment  variable  is  used,  and  if that is unset, an in-process\ndefault is provided.\n"
                },
                {
                    "name": "-fmodule-only",
                    "content": "Only emit the Compiled Module Interface, inhibiting any object file.\n"
                },
                {
                    "name": "-fms-extensions",
                    "content": "Disable Wpedantic warnings about constructs used in MFC, such as implicit int and getting\na pointer to member function via non-standard syntax.\n"
                },
                {
                    "name": "-fnew-inheriting-ctors",
                    "content": "Enable the P0136 adjustment to the semantics of C++11 constructor inheritance.   This  is\npart  of  C++17  but also considered to be a Defect Report against C++11 and C++14.  This\nflag is enabled by default unless -fabi-version=10 or lower is specified.\n"
                },
                {
                    "name": "-fnew-ttp-matching",
                    "content": "Enable the P0522 resolution to Core issue 150, template template parameters  and  default\narguments:  this  allows  a template with default template arguments as an argument for a\ntemplate template parameter with fewer template parameters.   This  flag  is  enabled  by\ndefault for -std=c++17.\n"
                },
                {
                    "name": "-fno-nonansi-builtins",
                    "content": "Disable  built-in  declarations  of functions that are not mandated by ANSI/ISO C.  These\ninclude \"ffs\", \"alloca\", \"exit\", \"index\", \"bzero\", \"conjf\", and other related functions.\n"
                },
                {
                    "name": "-fnothrow-opt",
                    "content": "Treat a throw() exception specification as if  it  were  a  \"noexcept\"  specification  to\nreduce  or  eliminate  the  text  size  overhead relative to a function with no exception\nspecification.   If  the  function  has  local  variables  of  types   with   non-trivial\ndestructors,  the exception specification actually makes the function smaller because the\nEH cleanups for those variables can be optimized away.  The semantic effect  is  that  an\nexception thrown out of a function with such an exception specification results in a call\nto \"terminate\" rather than \"unexpected\".\n"
                },
                {
                    "name": "-fno-operator-names",
                    "content": "Do  not  treat  the operator name keywords \"and\", \"bitand\", \"bitor\", \"compl\", \"not\", \"or\"\nand \"xor\" as synonyms as keywords.\n"
                },
                {
                    "name": "-fno-optional-diags",
                    "content": "Disable diagnostics that the standard says a compiler does not need to issue.  Currently,\nthe only such diagnostic issued by G++ is the one for a  name  having  multiple  meanings\nwithin a class.\n"
                },
                {
                    "name": "-fpermissive",
                    "content": "Downgrade some diagnostics about nonconformant code from errors to warnings.  Thus, using\n-fpermissive allows some nonconforming code to compile.\n"
                },
                {
                    "name": "-fno-pretty-templates",
                    "content": "When  an  error  message  refers to a specialization of a function template, the compiler\nnormally prints the signature of the template followed by the template arguments and  any\ntypedefs or typenames in the signature (e.g. \"void f(T) [with T = int]\" rather than \"void\nf(int)\")  so that it's clear which template is involved.  When an error message refers to\na specialization of a class template, the compiler  omits  any  template  arguments  that\nmatch  the  default  template  arguments for that template.  If either of these behaviors\nmake it harder  to  understand  the  error  message  rather  than  easier,  you  can  use\n-fno-pretty-templates to disable them.\n"
                },
                {
                    "name": "-fno-rtti",
                    "content": "Disable generation of information about every class with virtual functions for use by the\nC++  run-time  type  identification features (\"dynamiccast\" and \"typeid\").  If you don't\nuse those parts of the language, you can save some space by using this flag.   Note  that\nexception  handling  uses  the  same  information,  but  G++  generates it as needed. The\n\"dynamiccast\" operator can still be used for casts that do  not  require  run-time  type\ninformation, i.e. casts to \"void *\" or to unambiguous base classes.\n\nMixing  code  compiled  with  -frtti with that compiled with -fno-rtti may not work.  For\nexample, programs may fail to link if a class compiled with -fno-rtti is used as  a  base\nfor a class compiled with -frtti.\n"
                },
                {
                    "name": "-fsized-deallocation",
                    "content": "Enable the built-in global declarations\n\nvoid operator delete (void *, std::sizet) noexcept;\nvoid operator delete[] (void *, std::sizet) noexcept;\n\nas  introduced  in  C++14.   This  is  useful  for  user-defined replacement deallocation\nfunctions that, for example, use the size of the  object  to  make  deallocation  faster.\nEnabled by default under -std=c++14 and above.  The flag -Wsized-deallocation warns about\nplaces that might want to add a definition.\n"
                },
                {
                    "name": "-fstrict-enums",
                    "content": "Allow  the  compiler to optimize using the assumption that a value of enumerated type can\nonly be one of the values of the enumeration (as defined in the C++ standard;  basically,\na value that can be represented in the minimum number of bits needed to represent all the\nenumerators).   This assumption may not be valid if the program uses a cast to convert an\narbitrary integer value to the enumerated type.\n"
                },
                {
                    "name": "-fstrong-eval-order",
                    "content": "Evaluate member access, array subscripting, and shift expressions in left-to-right order,\nand evaluate assignment in right-to-left order, as adopted for C++17.  Enabled by default\nwith -std=c++17.  -fstrong-eval-order=some enables just the ordering of member access and\nshift expressions, and is the default without -std=c++17.\n"
                },
                {
                    "name": "-ftemplate-backtrace-limit=_",
                    "content": "Set the maximum number of template instantiation notes for a single warning or  error  to\nn.  The default value is 10.\n"
                },
                {
                    "name": "-ftemplate-depth=_",
                    "content": "Set  the  maximum instantiation depth for template classes to n.  A limit on the template\ninstantiation depth  is  needed  to  detect  endless  recursions  during  template  class\ninstantiation.  ANSI/ISO C++ conforming programs must not rely on a maximum depth greater\nthan  17  (changed  to 1024 in C++11).  The default value is 900, as the compiler can run\nout of stack space before hitting 1024 in some situations.\n"
                },
                {
                    "name": "-fno-threadsafe-statics",
                    "content": "Do not emit the extra code to use the routines specified in the C++ ABI  for  thread-safe\ninitialization of local statics.  You can use this option to reduce code size slightly in\ncode that doesn't need to be thread-safe.\n"
                },
                {
                    "name": "-fuse-cxa-atexit",
                    "content": "Register  destructors  for  objects  with static storage duration with the \"cxaatexit\"\nfunction rather than the \"atexit\" function.  This option is required for fully standards-\ncompliant handling of static destructors, but only  works  if  your  C  library  supports\n\"cxaatexit\".\n"
                },
                {
                    "name": "-fno-use-cxa-get-exception-ptr",
                    "content": "Don't    use    the    \"cxagetexceptionptr\"    runtime    routine.     This   causes\n\"std::uncaughtexception\" to be incorrect, but is necessary if the runtime routine is not\navailable.\n"
                },
                {
                    "name": "-fvisibility-inlines-hidden",
                    "content": "This switch declares that the user  does  not  attempt  to  compare  pointers  to  inline\nfunctions  or  methods  where  the  addresses of the two functions are taken in different\nshared objects.\n\nThe effect of this is that GCC may, effectively, mark inline methods with  \"attribute\n((visibility (\"hidden\")))\" so that they do not appear in the export table of a DSO and do\nnot  require a PLT indirection when used within the DSO.  Enabling this option can have a\ndramatic effect on load and link times of a DSO as it massively reduces the size  of  the\ndynamic export table when the library makes heavy use of templates.\n\nThe  behavior  of  this  switch  is  not  quite the same as marking the methods as hidden\ndirectly, because it does not affect static variables local to the function or cause  the\ncompiler to deduce that the function is defined in only one shared object.\n\nYou  may  mark  a  method  as  having a visibility explicitly to negate the effect of the\nswitch for that method.  For example, if you do want to compare pointers to a  particular\ninline  method,  you  might  mark it as having default visibility.  Marking the enclosing\nclass with explicit visibility has no effect.\n\nExplicitly instantiated inline methods are unaffected by this  option  as  their  linkage\nmight otherwise cross a shared library boundary.\n"
                },
                {
                    "name": "-fvisibility-ms-compat",
                    "content": "This  flag attempts to use visibility settings to make GCC's C++ linkage model compatible\nwith that of Microsoft Visual Studio.\n\nThe flag makes these changes to GCC's linkage model:\n\n1.  It sets the default visibility to \"hidden\", like -fvisibility=hidden.\n\n2.  Types, but not their members, are not hidden by default.\n\n3.  The  One  Definition  Rule  is  relaxed  for  types   without   explicit   visibility\nspecifications  that  are  defined in more than one shared object: those declarations\nare permitted if they are permitted when this option is not used.\n\nIn new code it is better to use -fvisibility=hidden and export  those  classes  that  are\nintended  to  be  externally  visible.   Unfortunately  it  is possible for code to rely,\nperhaps accidentally, on the Visual Studio behavior.\n\nAmong the consequences of these changes are that static data members  of  the  same  type\nwith the same name but defined in different shared objects are different, so changing one\ndoes  not  change  the  other; and that pointers to function members defined in different\nshared objects may not compare equal.  When this flag is given, it is a violation of  the\nODR to define types with the same name differently.\n"
                },
                {
                    "name": "-fno-weak",
                    "content": "Do  not  use  weak symbol support, even if it is provided by the linker.  By default, G++\nuses weak symbols if they are available.  This option exists only for testing, and should\nnot be used by end-users; it results in inferior code and has no benefits.   This  option\nmay be removed in a future release of G++.\n"
                },
                {
                    "name": "-fext-numeric-literals",
                    "content": "Accept  imaginary,  fixed-point,  or  machine-defined  literal  number  suffixes  as  GNU\nextensions.  When this option is turned off these suffixes are  treated  as  C++11  user-\ndefined  literal  numeric suffixes.  This is on by default for all pre-C++11 dialects and\nall GNU dialects: -std=c++98, -std=gnu++98, -std=gnu++11, -std=gnu++14.  This  option  is\noff by default for ISO C++11 onwards (-std=c++11, ...).\n"
                },
                {
                    "name": "-nostdinc++",
                    "content": "Do  not search for header files in the standard directories specific to C++, but do still\nsearch the other standard directories.  (This  option  is  used  when  building  the  C++\nlibrary.)\n"
                },
                {
                    "name": "-flang-info-include-translate",
                    "content": ""
                },
                {
                    "name": "-flang-info-include-translate-not",
                    "content": ""
                },
                {
                    "name": "-flang-info-include-translate=_",
                    "content": "Inform of include translation events.  The first will note accepted include translations,\nthe  second  will  note  declined  include  translations.  The header form will inform of\ninclude translations relating to that specific header.  If header is of the  form  \"user\"\nor  \"<system>\"  it will be resolved to a specific user or system header using the include\npath.\n"
                },
                {
                    "name": "-flang-info-module-cmi",
                    "content": ""
                },
                {
                    "name": "-flang-info-module-cmi=_",
                    "content": "Inform of Compiled Module  Interface  pathnames.   The  first  will  note  all  read  CMI\npathnames.   The  module  form will not reading a specific module's CMI.  module may be a\nnamed module or a header-unit (the latter indicated by either being a pathname containing\ndirectory separators or enclosed in \"<>\" or \"\").\n"
                },
                {
                    "name": "-stdlib=_",
                    "content": "When G++ is configured to support this option, it allows specification of  alternate  C++\nruntime libraries.  Two options are available: libstdc++ (the default, native C++ runtime\nfor  G++)  and  libc++ which is the C++ runtime installed on some operating systems (e.g.\nDarwin versions from Darwin11 onwards).  The option switches G++ to use the headers  from\nthe  specified library and to emit \"-lstdc++\" or \"-lc++\" respectively, when a C++ runtime\nis required for linking.\n\nIn addition, these warning options have meanings only for C++ programs:\n"
                },
                {
                    "name": "-Wabi-tag",
                    "content": "Warn when a type with an ABI tag is used in a context that does not have  that  ABI  tag.\nSee C++ Attributes for more information about ABI tags.\n"
                },
                {
                    "name": "-Wcomma-subscript",
                    "content": "Warn  about  uses of a comma expression within a subscripting expression.  This usage was\ndeprecated in C++20 and is going to be removed in C++23.   However,  a  comma  expression\nwrapped in \"( )\" is not deprecated.  Example:\n\nvoid f(int *a, int b, int c) {\na[b,c];     // deprecated in C++20, invalid in C++23\na[(b,c)];   // OK\n}\n\nIn  C++23  it  is  valid  to  have  comma  separated  expressions  in a subscript when an\noverloaded subscript operator is found  and  supports  the  right  number  and  types  of\narguments.  G++ will accept the formerly valid syntax for code that is not valid in C++23\nbut used to be valid but deprecated in C++20 with a pedantic warning that can be disabled\nwith -Wno-comma-subscript.\n\nEnabled by default with -std=c++20 unless -Wno-deprecated, and with -std=c++23 regardless\nof -Wno-deprecated.\n"
                },
                {
                    "name": "-Wctad-maybe-unsupported",
                    "content": "Warn  when  performing  class  template  argument  deduction  (CTAD)  on  a  type with no\nexplicitly written deduction guides.  This  warning  will  point  out  cases  where  CTAD\nsucceeded  only  because  the  compiler  synthesized the implicit deduction guides, which\nmight not be what the programmer intended.  Certain style guides allow CTAD only on types\nthat specifically \"opt-in\"; i.e., on types that  are  designed  to  support  CTAD.   This\nwarning can be suppressed with the following pattern:\n\nstruct allowctadt; // any name works\ntemplate <typename T> struct S {\nS(T) { }\n};\n// Guide with incomplete parameter type will never be considered.\nS(allowctadt) -> S<void>;\n"
                },
                {
                    "name": "-Wctor-dtor-privacy",
                    "content": "Warn  when  a  class  seems  unusable because all the constructors or destructors in that\nclass are private, and it has neither friends nor public static member  functions.   Also\nwarn  if  there  are  no  non-private  methods,  and  there's at least one private member\nfunction that isn't a constructor or destructor.\n"
                },
                {
                    "name": "-Wdangling-reference",
                    "content": "Warn when a reference is bound to a temporary whose lifetime has ended.  For example:\n\nint n = 1;\nconst int& r = std::max(n - 1, n + 1); // r is dangling\n\nIn the example above, two temporaries are created, one for each argument, and a reference\nto one of the temporaries is returned.  However, both temporaries are  destroyed  at  the\nend  of the full expression, so the reference \"r\" is dangling.  This warning also detects\ndangling references in member initializer lists:\n\nconst int& f(const int& i) { return i; }\nstruct S {\nconst int &r; // r is dangling\nS() : r(f(10)) { }\n};\n\nMember functions are checked as well, but only their object argument:\n\nstruct S {\nconst S& self () { return *this; }\n};\nconst S& s = S().self(); // s is dangling\n\nCertain functions are safe in this respect, for example \"std::usefacet\": they  take  and\nreturn  a  reference,  but  they  don't  return  one of its arguments, which can fool the\nwarning.  Such functions can  be  excluded  from  the  warning  by  wrapping  them  in  a\n\"#pragma\":\n\n#pragma GCC diagnostic push\n#pragma GCC diagnostic ignored \"-Wdangling-reference\"\nconst T& foo (const T&) { ... }\n#pragma GCC diagnostic pop\n\n-Wdangling-reference also warns about code like\n\nauto p = std::minmax(1, 2);\n\nwhere  \"std::minmax\"  returns  \"std::pair<const  int&,  const int&>\", and both references\ndangle after the end of the full expression that contains the call to \"std::minmax\".\n\nThis warning is enabled by -Wextra.\n"
                },
                {
                    "name": "-Wdelete-non-virtual-dtor",
                    "content": "Warn when \"delete\" is used to destroy an instance of a class that has  virtual  functions\nand non-virtual destructor. It is unsafe to delete an instance of a derived class through\na  pointer  to  a  base class if the base class does not have a virtual destructor.  This\nwarning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wdeprecated-copy",
                    "content": "Warn that the implicit declaration of a copy constructor or copy assignment  operator  is\ndeprecated if the class has a user-provided copy constructor or copy assignment operator,\nin  C++11 and up.  This warning is enabled by -Wextra.  With -Wdeprecated-copy-dtor, also\ndeprecate if the class has a user-provided destructor.\n"
                },
                {
                    "name": "-Wno-deprecated-enum-enum-conversion",
                    "content": "Disable the warning about the case when the usual arithmetic conversions are  applied  on\noperands  where  one  is  of enumeration type and the other is of a different enumeration\ntype.  This conversion was deprecated in C++20.  For example:\n\nenum E1 { e };\nenum E2 { f };\nint k = f - e;\n\n-Wdeprecated-enum-enum-conversion is enabled by default with  -std=c++20.   In  pre-C++20\ndialects, this warning can be enabled by -Wenum-conversion.\n"
                },
                {
                    "name": "-Wno-deprecated-enum-float-conversion",
                    "content": "Disable  the  warning about the case when the usual arithmetic conversions are applied on\noperands where one is of enumeration type and the other  is  of  a  floating-point  type.\nThis conversion was deprecated in C++20.  For example:\n\nenum E1 { e };\nenum E2 { f };\nbool b = e <= 3.7;\n\n-Wdeprecated-enum-float-conversion  is  enabled by default with -std=c++20.  In pre-C++20\ndialects, this warning can be enabled by -Wenum-conversion.\n"
                },
                {
                    "name": "-Wno-init-list-lifetime",
                    "content": "Do not warn about uses of \"std::initializerlist\" that are likely to result  in  dangling\npointers.   Since the underlying array for an \"initializerlist\" is handled like a normal\nC++ temporary object, it is easy to inadvertently keep a pointer to the  array  past  the\nend of the array's lifetime.  For example:\n\n*   If  a  function returns a temporary \"initializerlist\", or a local \"initializerlist\"\nvariable, the array's lifetime ends at the end of the return statement, so the  value\nreturned has a dangling pointer.\n\n*   If a new-expression creates an \"initializerlist\", the array only lives until the end\nof  the  enclosing  full-expression,  so  the  \"initializerlist\"  in  the heap has a\ndangling pointer.\n\n*   When an \"initializerlist\" variable is assigned  from  a  brace-enclosed  initializer\nlist,  the  temporary  array  created for the right side of the assignment only lives\nuntil the end of the full-expression, so at the next statement the \"initializerlist\"\nvariable has a dangling pointer.\n\n// li's initial underlying array lives as long as li\nstd::initializerlist<int> li = { 1,2,3 };\n// assignment changes li to point to a temporary array\nli = { 4, 5 };\n// now the temporary is gone and li has a dangling pointer\nint i = li.begin()[0] // undefined behavior\n\n*   When a list constructor  stores  the  \"begin\"  pointer  from  the  \"initializerlist\"\nargument,  this  doesn't  extend the lifetime of the array, so if a class variable is\nconstructed from a temporary \"initializerlist\", the pointer is left dangling by  the\nend of the variable declaration statement.\n"
                },
                {
                    "name": "-Winvalid-constexpr",
                    "content": "Warn  when  a  function  never produces a constant expression.  In C++20 and earlier, for\nevery \"constexpr\" function and function template, there must  be  at  least  one  set  of\nfunction  arguments in at least one instantiation such that an invocation of the function\nor constructor could be an evaluated subexpression of a core constant expression.   C++23\nremoved  this  restriction,  so  it's  possible to have a function or a function template\nmarked \"constexpr\" for which no invocation satisfies the requirements of a core  constant\nexpression.\n\nThis warning is enabled as a pedantic warning by default in C++20 and earlier.  In C++23,\n-Winvalid-constexpr  can be turned on, in which case it will be an ordinary warning.  For\nexample:\n\nvoid f (int& i);\nconstexpr void\ng (int& i)\n{\n// Warns by default in C++20, in C++23 only with -Winvalid-constexpr.\nf(i);\n}\n"
                },
                {
                    "name": "-Winvalid-imported-macros",
                    "content": "Verify all imported macro definitions are valid at the end of compilation.  This  is  not\nenabled  by default, as it requires additional processing to determine.  It may be useful\nwhen preparing sets of header-units to ensure consistent macros.\n"
                },
                {
                    "name": "-Wno-literal-suffix",
                    "content": "Do not warn when a string or character literal is followed by a ud-suffix which does  not\nbegin  with  an  underscore.   As  a  conforming  extension,  GCC treats such suffixes as\nseparate preprocessing tokens in order to maintain backwards compatibility with code that\nuses formatting macros from \"<inttypes.h>\".  For example:\n\n#define STDCFORMATMACROS\n#include <inttypes.h>\n#include <stdio.h>\n\nint main() {\nint64t i64 = 123;\nprintf(\"My int64: %\" PRId64\"\\n\", i64);\n}\n\nIn this case, \"PRId64\" is treated as a separate preprocessing token.\n\nThis option also controls warnings when a user-defined literal operator is declared  with\na  literal  suffix  identifier  that  doesn't  begin  with  an underscore. Literal suffix\nidentifiers that don't begin with an underscore are reserved for future standardization.\n\nThese warnings are enabled by default.\n"
                },
                {
                    "name": "-Wno-narrowing",
                    "content": "For C++11 and later  standards,  narrowing  conversions  are  diagnosed  by  default,  as\nrequired  by the standard.  A narrowing conversion from a constant produces an error, and\na narrowing conversion  from  a  non-constant  produces  a  warning,  but  -Wno-narrowing\nsuppresses  the  diagnostic.   Note  that this does not affect the meaning of well-formed\ncode; narrowing conversions are still considered ill-formed in SFINAE contexts.\n\nWith -Wnarrowing in C++98, warn when a narrowing conversion prohibited  by  C++11  occurs\nwithin { }, e.g.\n\nint i = { 2.2 }; // error: narrowing from double to int\n\nThis flag is included in -Wall and -Wc++11-compat.\n"
                },
                {
                    "name": "-Wnoexcept",
                    "content": "Warn  when  a noexcept-expression evaluates to false because of a call to a function that\ndoes not have a non-throwing exception specification (i.e. throw() or \"noexcept\") but  is\nknown by the compiler to never throw an exception.\n"
                },
                {
                    "name": "-Wnoexcept-type",
                    "content": "Warn  if  the C++17 feature making \"noexcept\" part of a function type changes the mangled\nname of a symbol relative to C++14.  Enabled by -Wabi and -Wc++17-compat.\n\nAs an example:\n\ntemplate <class T> void f(T t) { t(); };\nvoid g() noexcept;\nvoid h() { f(g); }\n\nIn C++14, \"f\" calls \"f<void(*)()>\", but in C++17 it calls \"f<void(*)()noexcept>\".\n"
                },
                {
                    "name": "-Wclass-memaccess",
                    "content": "Warn when the destination of a call to a raw memory function such as \"memset\" or \"memcpy\"\nis an object of class type, and when writing into such an object might bypass  the  class\nnon-trivial  or  deleted  constructor  or  copy  assignment, violate const-correctness or\nencapsulation, or corrupt virtual table pointers.  Modifying the representation  of  such\nobjects may violate invariants maintained by member functions of the class.  For example,\nthe  call  to  \"memset\" below is undefined because it modifies a non-trivial class object\nand is, therefore, diagnosed.  The safe way to either initialize or clear the storage  of\nobjects  of such types is by using the appropriate constructor or assignment operator, if\none is available.\n\nstd::string str = \"abc\";\nmemset (&str, 0, sizeof str);\n\nThe -Wclass-memaccess option is enabled by -Wall.  Explicitly casting the pointer to  the\nclass  object  to  \"void  *\"  or  to a type that can be safely accessed by the raw memory\nfunction suppresses the warning.\n"
                },
                {
                    "name": "-Wnon-virtual-dtor",
                    "content": "Warn when a class has virtual functions and an accessible non-virtual  destructor  itself\nor  in  an  accessible polymorphic base class, in which case it is possible but unsafe to\ndelete an instance of a derived class through a pointer  to  the  class  itself  or  base\nclass.    This   warning   is  automatically  enabled  if  -Weffc++  is  specified.   The\n-Wdelete-non-virtual-dtor option (enabled by -Wall) should be preferred because it  warns\nabout the unsafe cases without false positives.\n"
                },
                {
                    "name": "-Wregister",
                    "content": "Warn on uses of the \"register\" storage class specifier, except when it is part of the GNU\nExplicit  Register  Variables  extension.   The  use of the \"register\" keyword as storage\nclass specifier has been deprecated in C++11 and removed in C++17.   Enabled  by  default\nwith -std=c++17.\n"
                },
                {
                    "name": "-Wreorder",
                    "content": "Warn  when the order of member initializers given in the code does not match the order in\nwhich they must be executed.  For instance:\n\nstruct A {\nint i;\nint j;\nA(): j (0), i (1) { }\n};\n\nThe compiler rearranges the member initializers for \"i\" and \"j\" to match the  declaration\norder  of  the  members,  emitting  a warning to that effect.  This warning is enabled by\n-Wall.\n"
                },
                {
                    "name": "-Wno-pessimizing-move",
                    "content": "This warning warns when a call to \"std::move\" prevents copy elision.  A typical  scenario\nwhen  copy  elision  can  occur is when returning in a function with a class return type,\nwhen the expression being returned is the name of a non-volatile automatic object, and is\nnot a function parameter, and has the same type as the function return type.\n\nstruct T {\n...\n};\nT fn()\n{\nT t;\n...\nreturn std::move (t);\n}\n\nBut in this example, the \"std::move\" call prevents copy elision.\n\nThis warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wno-redundant-move",
                    "content": "This warning warns about redundant calls to \"std::move\"; that is, when a  move  operation\nwould  have  been  performed even without the \"std::move\" call.  This happens because the\ncompiler is forced to treat the object as if it were an rvalue in certain situations such\nas returning a local variable, where copy elision isn't applicable.  Consider:\n\nstruct T {\n...\n};\nT fn(T t)\n{\n...\nreturn std::move (t);\n}\n\nHere, the \"std::move\" call is redundant.  Because G++ implements Core Issue 1579, another\nexample is:\n\nstruct T { // convertible to U\n...\n};\nstruct U {\n...\n};\nU fn()\n{\nT t;\n...\nreturn std::move (t);\n}\n\nIn this example, copy elision isn't applicable because the type of the  expression  being\nreturned  and  the  function return type differ, yet G++ treats the return value as if it\nwere designated by an rvalue.\n\nThis warning is enabled by -Wextra.\n"
                },
                {
                    "name": "-Wrange-loop-construct",
                    "content": "This warning warns when a C++ range-based for-loop is creating an unnecessary copy.  This\ncan happen when the range declaration is not a reference, but probably  should  be.   For\nexample:\n\nstruct S { char arr[128]; };\nvoid fn () {\nS arr[5];\nfor (const auto x : arr) { ... }\n}\n\nIt  does  not  warn when the type being copied is a trivially-copyable type whose size is\nless than 64 bytes.\n\nThis warning also warns when a loop variable in a  range-based  for-loop  is  initialized\nwith a value of a different type resulting in a copy.  For example:\n\nvoid fn() {\nint arr[10];\nfor (const double &x : arr) { ... }\n}\n\nIn  the  example above, in every iteration of the loop a temporary value of type \"double\"\nis created and destroyed, to which the reference \"const double &\" is bound.\n\nThis warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wredundant-tags",
                    "content": "Warn about redundant class-key and enum-key in references to class types  and  enumerated\ntypes  in  contexts  where  the  key can be eliminated without causing an ambiguity.  For\nexample:\n\nstruct foo;\nstruct foo *p;   // warn that keyword struct can be eliminated\n\nOn the other hand, in this example there is no warning:\n\nstruct foo;\nvoid foo ();   // \"hides\" struct foo\nvoid bar (struct foo&);  // no warning, keyword struct is necessary\n"
                },
                {
                    "name": "-Wno-subobject-linkage",
                    "content": "Do not warn if a class type has a base or a field whose type uses the anonymous namespace\nor depends on a type with no linkage.  If a type A  depends  on  a  type  B  with  no  or\ninternal  linkage,  defining  it  in multiple translation units would be an ODR violation\nbecause the meaning of B is different in each translation unit.  If A only appears  in  a\nsingle  translation  unit,  the  best  way  to silence the warning is to give it internal\nlinkage by putting it in an anonymous namespace as well.  The compiler doesn't give  this\nwarning  for  types  defined  in the main .C file, as those are unlikely to have multiple\ndefinitions.  -Wsubobject-linkage is enabled by default.\n"
                },
                {
                    "name": "-Weffc++",
                    "content": "Warn about violations of the following style guidelines from Scott Meyers' Effective  C++\nseries of books:\n\n*   Define  a  copy  constructor and an assignment operator for classes with dynamically-\nallocated memory.\n\n*   Prefer initialization to assignment in constructors.\n\n*   Have \"operator=\" return a reference to *this.\n\n*   Don't try to return a reference when you must return an object.\n\n*   Distinguish between prefix and postfix forms of increment and decrement operators.\n\n*   Never overload \"&&\", \"||\", or \",\".\n\nThis option also enables -Wnon-virtual-dtor, which is  also  one  of  the  effective  C++\nrecommendations.   However,  the  check  is  extended  to  warn about the lack of virtual\ndestructor in accessible non-polymorphic bases classes too.\n\nWhen selecting this option, be aware that the standard library headers do not obey all of\nthese guidelines; use grep -v to filter out those warnings.\n"
                },
                {
                    "name": "-Wno-exceptions",
                    "content": "Disable the warning about the case when an  exception  handler  is  shadowed  by  another\nhandler, which can point out a wrong ordering of exception handlers.\n"
                },
                {
                    "name": "-Wstrict-null-sentinel",
                    "content": "Warn  about the use of an uncasted \"NULL\" as sentinel.  When compiling only with GCC this\nis a valid sentinel, as \"NULL\" is defined to \"null\".  Although it  is  a  null  pointer\nconstant  rather  than  a  null  pointer,  it  is  guaranteed to be of the same size as a\npointer.  But this use is not portable across different compilers.\n"
                },
                {
                    "name": "-Wno-non-template-friend",
                    "content": "Disable warnings when non-template friend functions are declared within a  template.   In\nvery  old  versions  of GCC that predate implementation of the ISO standard, declarations\nsuch as friend int foo(int), where the name of the friend is an unqualified-id, could  be\ninterpreted  as a particular specialization of a template function; the warning exists to\ndiagnose compatibility problems, and is enabled by default.\n"
                },
                {
                    "name": "-Wold-style-cast",
                    "content": "Warn if an old-style (C-style) cast to a non-void type is used within a C++ program.  The\nnew-style casts (\"dynamiccast\", \"staticcast\", \"reinterpretcast\", and \"constcast\") are\nless vulnerable to unintended effects and much easier to search for.\n"
                },
                {
                    "name": "-Woverloaded-virtual",
                    "content": ""
                },
                {
                    "name": "-Woverloaded-virtual=_",
                    "content": "Warn when a function declaration hides virtual functions from a base class.  For example,\nin:\n\nstruct A {\nvirtual void f();\n};\n\nstruct B: public A {\nvoid f(int); // does not override\n};\n\nthe \"A\" class version of \"f\" is hidden in \"B\", and code like:\n\nB* b;\nb->f();\n\nfails to compile.\n\nIn cases where the different signatures are not an accident, the simplest solution is  to\nadd  a  using-declaration  to  the  derived  class to un-hide the base function, e.g. add\n\"using A::f;\" to \"B\".\n\nThe optional level suffix controls the behavior when all the declarations in the  derived\nclass override virtual functions in the base class, even if not all of the base functions\nare overridden:\n\nstruct C {\nvirtual void f();\nvirtual void f(int);\n};\n\nstruct D: public C {\nvoid f(int); // does override\n}\n\nThis  pattern is less likely to be a mistake; if D is only used virtually, the user might\nhave decided that the base class semantics for some of the overloads are fine.\n\nAt level 1, this case does not warn; at level 2, it does.  -Woverloaded-virtual by itself\nselects level 2.  Level 1 is included in -Wall.\n"
                },
                {
                    "name": "-Wno-pmf-conversions",
                    "content": "Disable the diagnostic for converting a bound pointer  to  member  function  to  a  plain\npointer.\n"
                },
                {
                    "name": "-Wsign-promo",
                    "content": "Warn  when  overload resolution chooses a promotion from unsigned or enumerated type to a\nsigned type, over a conversion to an unsigned type of the same size.   Previous  versions\nof G++ tried to preserve unsignedness, but the standard mandates the current behavior.\n"
                },
                {
                    "name": "-Wtemplates",
                    "content": "Warn  when  a  primary  template  declaration is encountered.  Some coding rules disallow\ntemplates, and this may be used to enforce that rule.  The warning is inactive  inside  a\nsystem  header  file,  such  as  the  STL,  so  one  can still use the STL.  One may also\ninstantiate or specialize templates.\n"
                },
                {
                    "name": "-Wmismatched-new-delete",
                    "content": "Warn for mismatches between  calls  to  \"operator  new\"  or  \"operator  delete\"  and  the\ncorresponding call to the allocation or deallocation function.  This includes invocations\nof C++ \"operator delete\" with pointers returned from either mismatched forms of \"operator\nnew\", or from other functions that allocate objects for which the \"operator delete\" isn't\na  suitable  deallocator,  as well as calls to other deallocation functions with pointers\nreturned from \"operator new\" for which the deallocation function isn't suitable.\n\nFor example, the \"delete\" expression in  the  function  below  is  diagnosed  because  it\ndoesn't  match  the  array form of the \"new\" expression the pointer argument was returned\nfrom.  Similarly, the call to \"free\" is also diagnosed.\n\nvoid f ()\n{\nint *a = new int[n];\ndelete a;   // warning: mismatch in array forms of expressions\n\nchar *p = new char[n];\nfree (p);   // warning: mismatch between new and free\n}\n\nThe related option -Wmismatched-dealloc diagnoses  mismatches  involving  allocation  and\ndeallocation functions other than \"operator new\" and \"operator delete\".\n\n-Wmismatched-new-delete is included in -Wall.\n"
                },
                {
                    "name": "-Wmismatched-tags",
                    "content": "Warn  for declarations of structs, classes, and class templates and their specializations\nwith a class-key that does not match either the definition or the first declaration if no\ndefinition is provided.\n\nFor example, the declaration of \"struct Object\" in the argument list of  \"draw\"  triggers\nthe  warning.   To avoid it, either remove the redundant class-key \"struct\" or replace it\nwith \"class\" to match its definition.\n\nclass Object {\npublic:\nvirtual ~Object () = 0;\n};\nvoid draw (struct Object*);\n\nIt is not wrong to declare a class with the  class-key  \"struct\"  as  the  example  above\nshows.   The  -Wmismatched-tags  option is intended to help achieve a consistent style of\nclass declarations.  In code that is intended to be portable to  Windows-based  compilers\nthe  warning helps prevent unresolved references due to the difference in the mangling of\nsymbols declared with different class-keys.  The option can be used either on its own  or\nin conjunction with -Wredundant-tags.\n"
                },
                {
                    "name": "-Wmultiple-inheritance",
                    "content": "Warn  when  a  class  is  defined  with  multiple direct base classes.  Some coding rules\ndisallow multiple inheritance, and this may be used to enforce that rule.  The warning is\ninactive inside a system header file, such as the STL, so one can still use the STL.  One\nmay also define classes that indirectly use multiple inheritance.\n"
                },
                {
                    "name": "-Wvirtual-inheritance",
                    "content": "Warn when a class is defined with  a  virtual  direct  base  class.   Some  coding  rules\ndisallow multiple inheritance, and this may be used to enforce that rule.  The warning is\ninactive inside a system header file, such as the STL, so one can still use the STL.  One\nmay also define classes that indirectly use virtual inheritance.\n"
                },
                {
                    "name": "-Wno-virtual-move-assign",
                    "content": "Suppress  warnings  about  inheriting  from  a virtual base with a non-trivial C++11 move\nassignment operator.  This is dangerous because if the virtual base  is  reachable  along\nmore than one path, it is moved multiple times, which can mean both objects end up in the\nmoved-from  state.   If  the  move  assignment operator is written to avoid moving from a\nmoved-from object, this warning can be disabled.\n"
                },
                {
                    "name": "-Wnamespaces",
                    "content": "Warn when a namespace definition is opened.  Some coding rules disallow  namespaces,  and\nthis  may  be  used to enforce that rule.  The warning is inactive inside a system header\nfile, such as the STL, so one can still use the STL.  One may also use  using  directives\nand qualified names.\n"
                },
                {
                    "name": "-Wno-terminate",
                    "content": "Disable  the  warning  about a throw-expression that will immediately result in a call to\n\"terminate\".\n"
                },
                {
                    "name": "-Wno-vexing-parse",
                    "content": "Warn about the most vexing parse syntactic ambiguity.  This warns about the cases when  a\ndeclaration  looks  like  a  variable  definition, but the C++ language requires it to be\ninterpreted as a function declaration.  For instance:\n\nvoid f(double a) {\nint i();        // extern int i (void);\nint n(int(a));  // extern int n (int);\n}\n\nAnother example:\n\nstruct S { S(int); };\nvoid f(double a) {\nS x(int(a));   // extern struct S x (int);\nS y(int());    // extern struct S y (int (*) (void));\nS z();         // extern struct S z (void);\n}\n\nThe warning will suggest options how to deal with such an ambiguity; e.g., it can suggest\nremoving the parentheses or using braces instead.\n\nThis warning is enabled by default.\n"
                },
                {
                    "name": "-Wno-class-conversion",
                    "content": "Do not warn when a conversion function converts an object to the same  type,  to  a  base\nclass of that type, or to void; such a conversion function will never be called.\n"
                },
                {
                    "name": "-Wvolatile",
                    "content": "Warn about deprecated uses of the \"volatile\" qualifier.  This includes postfix and prefix\n\"++\"  and  \"--\" expressions of \"volatile\"-qualified types, using simple assignments where\nthe left operand is a \"volatile\"-qualified  non-class  type  for  their  value,  compound\nassignments   where   the   left   operand  is  a  \"volatile\"-qualified  non-class  type,\n\"volatile\"-qualified function  return  type,  \"volatile\"-qualified  parameter  type,  and\nstructured bindings of a \"volatile\"-qualified type.  This usage was deprecated in C++20.\n\nEnabled by default with -std=c++20.\n"
                },
                {
                    "name": "-Wzero-as-null-pointer-constant",
                    "content": "Warn when a literal 0 is used as null pointer constant.  This can be useful to facilitate\nthe conversion to \"nullptr\" in C++11.\n"
                },
                {
                    "name": "-Waligned-new",
                    "content": "Warn  about  a  new-expression  of  a  type  that  requires  greater  alignment  than the\nalignof(std::maxalignt) but uses an allocation function without an  explicit  alignment\nparameter. This option is enabled by -Wall.\n\nNormally  this  only  warns about global allocation functions, but -Waligned-new=all also\nwarns about class member allocation functions.\n"
                },
                {
                    "name": "-Wno-placement-new",
                    "content": ""
                },
                {
                    "name": "-Wplacement-new=_",
                    "content": "Warn about placement new expressions with undefined behavior,  such  as  constructing  an\nobject  in  a  buffer  that  is  smaller  than  the type of the object.  For example, the\nplacement new expression below is diagnosed because it attempts to construct an array  of\n64 integers in a buffer only 64 bytes large.\n\nchar buf [64];\nnew (buf) int[64];\n\nThis warning is enabled by default.\n\n-Wplacement-new=1\nThis  is  the default warning level of -Wplacement-new.  At this level the warning is\nnot issued for some strictly undefined constructs that GCC allows as  extensions  for\ncompatibility  with  legacy code.  For example, the following \"new\" expression is not\ndiagnosed at this level even though it has undefined behavior according  to  the  C++\nstandard because it writes past the end of the one-element array.\n\nstruct S { int n, a[1]; };\nS *s = (S *)malloc (sizeof *s + 31 * sizeof s->a[0]);\nnew (s->a)int [32]();\n\n-Wplacement-new=2\nAt  this  level,  in  addition to diagnosing all the same constructs as at level 1, a\ndiagnostic is also issued for placement new expressions that construct an  object  in\nthe  last  member  of  structure whose type is an array of a single element and whose\nsize is less than the size of the  object  being  constructed.   While  the  previous\nexample  would be diagnosed, the following construct makes use of the flexible member\narray extension to avoid the warning at level 2.\n\nstruct S { int n, a[]; };\nS *s = (S *)malloc (sizeof *s + 32 * sizeof s->a[0]);\nnew (s->a)int [32]();\n"
                },
                {
                    "name": "-Wcatch-value",
                    "content": ""
                },
                {
                    "name": "-Wcatch-value=_",
                    "content": "Warn about catch handlers that do not catch  via  reference.   With  -Wcatch-value=1  (or\n-Wcatch-value  for  short)  warn  about polymorphic class types that are caught by value.\nWith -Wcatch-value=2  warn  about  all  class  types  that  are  caught  by  value.  With\n-Wcatch-value=3  warn  about all types that are not caught by reference. -Wcatch-value is\nenabled by -Wall.\n"
                },
                {
                    "name": "-Wconditionally-supported",
                    "content": "Warn for conditionally-supported (C++11 [intro.defs]) constructs.\n"
                },
                {
                    "name": "-Wno-delete-incomplete",
                    "content": "Do not warn when deleting a  pointer  to  incomplete  type,  which  may  cause  undefined\nbehavior at runtime.  This warning is enabled by default.\n"
                },
                {
                    "name": "-Wextra-semi",
                    "content": "Warn about redundant semicolons after in-class function definitions.\n"
                },
                {
                    "name": "-Wno-inaccessible-base",
                    "content": "This  option  controls warnings when a base class is inaccessible in a class derived from\nit due to ambiguity.  The warning is enabled by  default.   Note  that  the  warning  for\nambiguous virtual bases is enabled by the -Wextra option.\n\nstruct A { int a; };\n\nstruct B : A { };\n\nstruct C : B, A { };\n"
                },
                {
                    "name": "-Wno-inherited-variadic-ctor",
                    "content": "Suppress  warnings  about  use  of  C++11  inheriting  constructors  when  the base class\ninherited from has a C variadic constructor; the warning is on  by  default  because  the\nellipsis is not inherited.\n"
                },
                {
                    "name": "-Wno-invalid-offsetof",
                    "content": "Suppress warnings from applying the \"offsetof\" macro to a non-POD type.  According to the\n2014  ISO  C++  standard, applying \"offsetof\" to a non-standard-layout type is undefined.\nIn existing C++ implementations, however, \"offsetof\" typically gives meaningful  results.\nThis  flag is for users who are aware that they are writing nonportable code and who have\ndeliberately chosen to ignore the warning about it.\n\nThe restrictions on \"offsetof\" may be relaxed in a future version of the C++ standard.\n"
                },
                {
                    "name": "-Wsized-deallocation",
                    "content": "Warn about a definition of an unsized deallocation function\n\nvoid operator delete (void *) noexcept;\nvoid operator delete[] (void *) noexcept;\n\nwithout a definition of the corresponding sized deallocation function\n\nvoid operator delete (void *, std::sizet) noexcept;\nvoid operator delete[] (void *, std::sizet) noexcept;\n\nor vice versa.  Enabled by -Wextra along with -fsized-deallocation.\n"
                },
                {
                    "name": "-Wsuggest-final-types",
                    "content": "Warn about types with virtual methods where code quality would be improved  if  the  type\nwere declared with the C++11 \"final\" specifier, or, if possible, declared in an anonymous\nnamespace.  This allows GCC to more aggressively devirtualize the polymorphic calls. This\nwarning is more effective with link-time optimization, where the  information  about  the\nclass hierarchy graph is more complete.\n"
                },
                {
                    "name": "-Wsuggest-final-methods",
                    "content": "Warn  about  virtual  methods  where  code  quality  would be improved if the method were\ndeclared with the C++11 \"final\" specifier, or, if possible, its type were declared in  an\nanonymous  namespace  or with the \"final\" specifier.  This warning is more effective with\nlink-time optimization, where the information about the class  hierarchy  graph  is  more\ncomplete.  It  is  recommended to first consider suggestions of -Wsuggest-final-types and\nthen rebuild with new annotations.\n"
                },
                {
                    "name": "-Wsuggest-override",
                    "content": "Warn about overriding virtual functions that are not marked with the \"override\" keyword.\n"
                },
                {
                    "name": "-Wuse-after-free",
                    "content": ""
                },
                {
                    "name": "-Wuse-after-free=_",
                    "content": "Warn about uses of pointers to dynamically allocated  objects  that  have  been  rendered\nindeterminate  by  a  call  to  a  deallocation  function.  The warning is enabled at all\noptimization levels but may yield different results with optimization than without.\n\n-Wuse-after-free=1\nAt level 1 the warning attempts to diagnose only unconditional uses of pointers  made\nindeterminate by a deallocation call or a successful call to \"realloc\", regardless of\nwhether  or  not the call resulted in an actual reallocatio of memory.  This includes\ndouble-\"free\" calls as  well  as  uses  in  arithmetic  and  relational  expressions.\nAlthough  undefined,  uses  of  indeterminate  pointers  in  equality (or inequality)\nexpressions are not diagnosed at this level.\n\n-Wuse-after-free=2\nAt level 2, in addition to unconditional uses, the warning also diagnoses conditional\nuses of pointers made indeterminate by a deallocation call.  As at level 2,  uses  in\nequality (or inequality) expressions are not diagnosed.  For example, the second call\nto \"free\" in the following function is diagnosed at this level:\n\nstruct A { int refcount; void *data; };\n\nvoid release (struct A *p)\n{\nint refcount = --p->refcount;\nfree (p);\nif (refcount == 0)\nfree (p->data);   // warning: p may be used after free\n}\n\n-Wuse-after-free=3\nAt  level  3,  the  warning also diagnoses uses of indeterminate pointers in equality\nexpressions.  All uses of indeterminate pointers are  undefined  but  equality  tests\nsometimes appear after calls to \"realloc\" as an attempt to determine whether the call\nresulted  in  relocating  the object to a different address.  They are diagnosed at a\nseparate level to aid legacy code gradually transition  to  safe  alternatives.   For\nexample, the equality test in the function below is diagnosed at this level:\n\nvoid adjustpointers (int, int);\n\nvoid grow (int p, int n)\n{\nint q = (int)realloc (p, n *= 2);\nif (q == p)\nreturn;\nadjustpointers ((int)q, n);\n}\n\nTo  avoid  the  warning at this level, store offsets into allocated memory instead of\npointers.  This approach  obviates  needing  to  adjust  the  stored  pointers  after\nreallocation.\n\n-Wuse-after-free=2 is included in -Wall.\n"
                },
                {
                    "name": "-Wuseless-cast",
                    "content": "Warn  when  an  expression  is  cast to its own type.  This warning does not occur when a\nclass object is converted to a non-reference type as that is a way to create a temporary:\n\nstruct S { };\nvoid g (S&&);\nvoid f (S&& arg)\n{\ng (S(arg)); // make arg prvalue so that it can bind to S&&\n}\n"
                },
                {
                    "name": "-Wno-conversion-null",
                    "content": "Do not warn for conversions between \"NULL\" and non-pointer  types.  -Wconversion-null  is\nenabled by default.\n"
                },
                {
                    "name": "Options Controlling Objective-C and Objective-C++ Dialects",
                    "content": "(NOTE: This manual does not describe the Objective-C and Objective-C++ languages themselves.\n\nThis  section describes the command-line options that are only meaningful for Objective-C and\nObjective-C++ programs.  You can also use  most  of  the  language-independent  GNU  compiler\noptions.  For example, you might compile a file someclass.m like this:\n\ngcc -g -fgnu-runtime -O -c someclass.m\n\nIn  this  example,  -fgnu-runtime  is  an option meant only for Objective-C and Objective-C++\nprograms; you can use the other options with any language supported by GCC.\n\nNote that since Objective-C is an extension of the C language, Objective-C  compilations  may\nalso use options specific to the C front-end (e.g., -Wtraditional).  Similarly, Objective-C++\ncompilations may use C++-specific options (e.g., -Wabi).\n\nHere is a list of options that are only for compiling Objective-C and Objective-C++ programs:\n"
                },
                {
                    "name": "-fconstant-string-class=_",
                    "content": "Use  class-name as the name of the class to instantiate for each literal string specified\nwith the syntax \"@\"...\"\".  The default  class  name  is  \"NXConstantString\"  if  the  GNU\nruntime  is  being  used,  and  \"NSConstantString\" if the NeXT runtime is being used (see\nbelow).  On Darwin (macOS, MacOS X) platforms, the -fconstant-cfstrings option,  if  also\npresent,  overrides the -fconstant-string-class setting and cause \"@\"...\"\" literals to be\nlaid out as constant CoreFoundation strings.  Note that -fconstant-cfstrings is an  alias\nfor the target-specific -mconstant-cfstrings equivalent.\n"
                },
                {
                    "name": "-fgnu-runtime",
                    "content": "Generate  object  code compatible with the standard GNU Objective-C runtime.  This is the\ndefault for most types of systems.\n"
                },
                {
                    "name": "-fnext-runtime",
                    "content": "Generate output compatible with the NeXT runtime.  This is  the  default  for  NeXT-based\nsystems,  including  Darwin  and Mac OS X.  The macro \"NEXTRUNTIME\" is predefined if\n(and only if) this option is used.\n"
                },
                {
                    "name": "-fno-nil-receivers",
                    "content": "Assume that  all  Objective-C  message  dispatches  (\"[receiver  message:arg]\")  in  this\ntranslation  unit  ensure that the receiver is not \"nil\".  This allows for more efficient\nentry points in the runtime to be used.  This option is  only  available  in  conjunction\nwith the NeXT runtime and ABI version 0 or 1.\n"
                },
                {
                    "name": "-fobjc-abi-version=_",
                    "content": "Use  version n of the Objective-C ABI for the selected runtime.  This option is currently\nsupported only for the NeXT runtime.  In that case, Version 0 is the traditional (32-bit)\nABI without support for properties and other Objective-C 2.0 additions.  Version 1 is the\ntraditional (32-bit) ABI with support for properties and other Objective-C 2.0 additions.\nVersion 2 is the modern (64-bit) ABI.  If nothing is specified, the default is Version  0\non 32-bit target machines, and Version 2 on 64-bit target machines.\n"
                },
                {
                    "name": "-fobjc-call-cxx-cdtors",
                    "content": "For each Objective-C class, check if any of its instance variables is a C++ object with a\nnon-trivial  default  constructor.   If  so, synthesize a special \"- (id) .cxxconstruct\"\ninstance method  which  runs  non-trivial  default  constructors  on  any  such  instance\nvariables,  in  order, and then return \"self\".  Similarly, check if any instance variable\nis a C++ object with a non-trivial destructor, and if so, synthesize a special \"-  (void)\n.cxxdestruct\" method which runs all such default destructors, in reverse order.\n\nThe  \"-  (id)  .cxxconstruct\" and \"- (void) .cxxdestruct\" methods thusly generated only\noperate on instance variables declared in the current Objective-C class,  and  not  those\ninherited  from  superclasses.   It  is  the responsibility of the Objective-C runtime to\ninvoke  all  such  methods  in  an  object's  inheritance   hierarchy.    The   \"-   (id)\n.cxxconstruct\"  methods  are  invoked  by  the  runtime  immediately  after a new object\ninstance is allocated; the \"-  (void)  .cxxdestruct\"  methods  are  invoked  immediately\nbefore the runtime deallocates an object instance.\n\nAs  of  this  writing,  only  the NeXT runtime on Mac OS X 10.4 and later has support for\ninvoking the \"- (id) .cxxconstruct\" and \"- (void) .cxxdestruct\" methods.\n"
                },
                {
                    "name": "-fobjc-direct-dispatch",
                    "content": "Allow fast jumps to the message dispatcher.  On Darwin this is accomplished via the  comm\npage.\n"
                },
                {
                    "name": "-fobjc-exceptions",
                    "content": "Enable  syntactic  support  for  structured exception handling in Objective-C, similar to\nwhat is offered by C++.  This option is required to use the  Objective-C  keywords  @try,\n@throw,  @catch,  @finally and @synchronized.  This option is available with both the GNU\nruntime and the NeXT runtime (but not available in conjunction with the NeXT  runtime  on\nMac OS X 10.2 and earlier).\n"
                },
                {
                    "name": "-fobjc-gc",
                    "content": "Enable garbage collection (GC) in Objective-C and Objective-C++ programs.  This option is\nonly  available with the NeXT runtime; the GNU runtime has a different garbage collection\nimplementation that does not require special compiler flags.\n"
                },
                {
                    "name": "-fobjc-nilcheck",
                    "content": "For the NeXT runtime with version 2 of the ABI,  check  for  a  nil  receiver  in  method\ninvocations before doing the actual method call.  This is the default and can be disabled\nusing  -fno-objc-nilcheck.   Class  methods  and super calls are never checked for nil in\nthis way no matter what this flag is set to.  Currently this flag does nothing  when  the\nGNU runtime, or an older version of the NeXT runtime ABI, is used.\n"
                },
                {
                    "name": "-fobjc-std=objc1",
                    "content": "Conform  to  the  language syntax of Objective-C 1.0, the language recognized by GCC 4.0.\nThis only affects the Objective-C additions to the C/C++ language;  it  does  not  affect\nconformance  to C/C++ standards, which is controlled by the separate C/C++ dialect option\nflags.  When this option is used with the  Objective-C  or  Objective-C++  compiler,  any\nObjective-C  syntax that is not recognized by GCC 4.0 is rejected.  This is useful if you\nneed to make sure that your Objective-C code can be compiled with older versions of GCC.\n"
                },
                {
                    "name": "-freplace-objc-classes",
                    "content": "Emit a special marker instructing ld(1) not to statically link in  the  resulting  object\nfile,  and  allow dyld(1) to load it in at run time instead.  This is used in conjunction\nwith the Fix-and-Continue debugging mode, where  the  object  file  in  question  may  be\nrecompiled  and dynamically reloaded in the course of program execution, without the need\nto restart  the  program  itself.   Currently,  Fix-and-Continue  functionality  is  only\navailable in conjunction with the NeXT runtime on Mac OS X 10.3 and later.\n"
                },
                {
                    "name": "-fzero-link",
                    "content": "When  compiling  for  the  NeXT  runtime,  the  compiler  ordinarily  replaces  calls  to\nobjcgetClass(\"...\") (when the name of the class is known at compile  time)  with  static\nclass  references that get initialized at load time, which improves run-time performance.\nSpecifying  the  -fzero-link  flag  suppresses  this  behavior  and   causes   calls   to\nobjcgetClass(\"...\")   to be retained.  This is useful in Zero-Link debugging mode, since\nit allows for individual class implementations to be modified during  program  execution.\nThe  GNU  runtime  currently always retains calls to objcgetclass(\"...\")  regardless of\ncommand-line options.\n"
                },
                {
                    "name": "-fno-local-ivars",
                    "content": "By default instance variables in Objective-C can  be  accessed  as  if  they  were  local\nvariables  from  within  the  methods of the class they're declared in.  This can lead to\nshadowing between instance variables and other variables declared either locally inside a\nclass method or globally with  the  same  name.   Specifying  the  -fno-local-ivars  flag\ndisables this behavior thus avoiding variable shadowing issues.\n"
                },
                {
                    "name": "-fivar-visibility=",
                    "content": "Set  the  default  instance  variable visibility to the specified option so that instance\nvariables declared outside the scope of any access modifier  directives  default  to  the\nspecified visibility.\n"
                },
                {
                    "name": "-gen-decls",
                    "content": "Dump  interface  declarations  for  all  classes  seen in the source file to a file named\nsourcename.decl.\n"
                },
                {
                    "name": "-Wassign-intercept",
                    "content": "Warn whenever an Objective-C assignment is being intercepted by the garbage collector.\n"
                },
                {
                    "name": "-Wno-property-assign-default",
                    "content": "Do not warn if a property for an Objective-C object has no assign semantics specified.\n"
                },
                {
                    "name": "-Wno-protocol",
                    "content": "If a class is declared to implement a protocol, a warning is issued for every  method  in\nthe  protocol  that  is not implemented by the class.  The default behavior is to issue a\nwarning for every method not explicitly implemented  in  the  class,  even  if  a  method\nimplementation  is  inherited  from the superclass.  If you use the -Wno-protocol option,\nthen methods inherited from the superclass are  considered  to  be  implemented,  and  no\nwarning is issued for them.\n"
                },
                {
                    "name": "-Wobjc-root-class",
                    "content": "Warn  if  a class interface lacks a superclass. Most classes will inherit from \"NSObject\"\n(or \"Object\") for example.  When declaring classes  intended  to  be  root  classes,  the\nwarning     can     be     suppressed     by     marking     their     interfaces    with\n\"attribute((objcrootclass))\".\n"
                },
                {
                    "name": "-Wselector",
                    "content": "Warn if multiple methods of different types  for  the  same  selector  are  found  during\ncompilation.   The  check  is  performed  on  the  list  of methods in the final stage of\ncompilation.  Additionally, a check  is  performed  for  each  selector  appearing  in  a\n@selector(...)   expression,  and a corresponding method for that selector has been found\nduring compilation.  Because these checks scan the  method  table  only  at  the  end  of\ncompilation,  these  warnings  are  not produced if the final stage of compilation is not\nreached, for example because an  error  is  found  during  compilation,  or  because  the\n-fsyntax-only option is being used.\n"
                },
                {
                    "name": "-Wstrict-selector-match",
                    "content": "Warn  if  multiple  methods  with  differing argument and/or return types are found for a\ngiven selector when attempting to send a message using this selector  to  a  receiver  of\ntype  \"id\"  or  \"Class\".   When  this  flag  is  off (which is the default behavior), the\ncompiler omits such warnings if any differences found are confined to  types  that  share\nthe same size and alignment.\n"
                },
                {
                    "name": "-Wundeclared-selector",
                    "content": "Warn  if  a  @selector(...)  expression  referring to an undeclared selector is found.  A\nselector is considered undeclared if no method with that name has  been  declared  before\nthe   @selector(...)   expression,  either  explicitly  in  an  @interface  or  @protocol\ndeclaration, or implicitly in an @implementation section.  This  option  always  performs\nits  checks  as  soon  as  a  @selector(...)  expression  is found, while -Wselector only\nperforms its checks in the final stage of compilation.  This  also  enforces  the  coding\nstyle convention that methods and selectors must be declared before being used.\n"
                },
                {
                    "name": "-print-objc-runtime-info",
                    "content": "Generate C header describing the largest structure that is passed by value, if any.\n"
                },
                {
                    "name": "Options to Control Diagnostic Messages Formatting",
                    "content": "Traditionally,  diagnostic  messages  have been formatted irrespective of the output device's\naspect (e.g. its width, ...).  You can  use  the  options  described  below  to  control  the\nformatting  algorithm  for  diagnostic messages, e.g. how many characters per line, how often\nsource location information should be reported.  Note that some language front ends  may  not\nhonor these options.\n"
                },
                {
                    "name": "-fmessage-length=_",
                    "content": "Try  to  format  error messages so that they fit on lines of about n characters.  If n is\nzero, then no line-wrapping is done; each error message appears on a single  line.   This\nis the default for all front ends.\n\nNote  -  this  option  also  affects the display of the #error and #warning pre-processor\ndirectives, and the deprecated function/type/variable attribute.   It  does  not  however\naffect the pragma GCC warning and pragma GCC error pragmas.\n"
                },
                {
                    "name": "-fdiagnostics-plain-output",
                    "content": "This  option  requests  that  diagnostic  output  look as plain as possible, which may be\nuseful when running dejagnu or other utilities that need to parse diagnostics output  and\nprefer  that  it  remain  more stable over time.  -fdiagnostics-plain-output is currently\nequivalent      to      the      following      options:      -fno-diagnostics-show-caret\n-fno-diagnostics-show-line-numbers   -fdiagnostics-color=never   -fdiagnostics-urls=never\n-fdiagnostics-path-format=separate-events In the  future,  if  GCC  changes  the  default\nappearance  of its diagnostics, the corresponding option to disable the new behavior will\nbe added to this list.\n"
                },
                {
                    "name": "-fdiagnostics-show-location=once",
                    "content": "Only meaningful in line-wrapping mode.  Instructs the  diagnostic  messages  reporter  to\nemit source location information once; that is, in case the message is too long to fit on\na  single  physical  line and has to be wrapped, the source location won't be emitted (as\nprefix) again, over and over, in subsequent continuation  lines.   This  is  the  default\nbehavior.\n"
                },
                {
                    "name": "-fdiagnostics-show-location=every-line",
                    "content": "Only  meaningful  in  line-wrapping  mode.  Instructs the diagnostic messages reporter to\nemit the same source location information (as prefix) for physical lines that result from\nthe process of breaking a message which is too long to fit on a single line.\n"
                },
                {
                    "name": "-fdiagnostics-color[=_",
                    "content": ""
                },
                {
                    "name": "-fno-diagnostics-color",
                    "content": "Use color in diagnostics.  WHEN is never, always, or auto.  The default  depends  on  how\nthe  compiler  has been configured, it can be any of the above WHEN options or also never\nif GCCCOLORS environment variable isn't present in the environment, and auto  otherwise.\nauto  makes  GCC  use  color  only  when  the  standard error is a terminal, and when not\nexecuting in an emacs shell.  The forms  -fdiagnostics-color  and  -fno-diagnostics-color\nare aliases for -fdiagnostics-color=always and -fdiagnostics-color=never, respectively.\n\nThe  colors  are  defined  by the environment variable GCCCOLORS.  Its value is a colon-\nseparated list of  capabilities  and  Select  Graphic  Rendition  (SGR)  substrings.  SGR\ncommands  are  interpreted by the terminal or terminal emulator.  (See the section in the\ndocumentation of your text terminal for permitted values and their meanings as  character\nattributes.)   These  substring  values are integers in decimal representation and can be\nconcatenated with semicolons.  Common values to concatenate include 1  for  bold,  4  for\nunderline,  5  for  blink,  7  for inverse, 39 for default foreground color, 30 to 37 for\nforeground colors, 90 to 97 for 16-color mode foreground colors, 38;5;0 to  38;5;255  for\n88-color and 256-color modes foreground colors, 49 for default background color, 40 to 47\nfor  background  colors,  100  to  107 for 16-color mode background colors, and 48;5;0 to\n48;5;255 for 88-color and 256-color modes background colors.\n\nThe default GCCCOLORS is\n\nerror=01;31:warning=01;35:note=01;36:range1=32:range2=34:locus=01:\\\nquote=01:path=01;36:fixit-insert=32:fixit-delete=31:\\\ndiff-filename=01:diff-hunk=32:diff-delete=31:diff-insert=32:\\\ntype-diff=01;32:fnname=01;32:targs=35\n\nwhere 01;31 is bold red, 01;35 is bold magenta, 01;36 is bold cyan, 32 is  green,  34  is\nblue, 01 is bold, and 31 is red.  Setting GCCCOLORS to the empty string disables colors.\nSupported capabilities are as follows.\n\n\"error=\"\nSGR substring for error: markers.\n\n\"warning=\"\nSGR substring for warning: markers.\n\n\"note=\"\nSGR substring for note: markers.\n\n\"path=\"\nSGR   substring   for   colorizing  paths  of  control-flow  events  as  printed  via\n-fdiagnostics-path-format=, such as the identifiers of individual  events  and  lines\nindicating interprocedural calls and returns.\n\n\"range1=\"\nSGR substring for first additional range.\n\n\"range2=\"\nSGR substring for second additional range.\n\n\"locus=\"\nSGR substring for location information, file:line or file:line:column etc.\n\n\"quote=\"\nSGR substring for information printed within quotes.\n\n\"fnname=\"\nSGR substring for names of C++ functions.\n\n\"targs=\"\nSGR substring for C++ function template parameter bindings.\n\n\"fixit-insert=\"\nSGR substring for fix-it hints suggesting text to be inserted or replaced.\n\n\"fixit-delete=\"\nSGR substring for fix-it hints suggesting text to be deleted.\n\n\"diff-filename=\"\nSGR substring for filename headers within generated patches.\n\n\"diff-hunk=\"\nSGR substring for the starts of hunks within generated patches.\n\n\"diff-delete=\"\nSGR substring for deleted lines within generated patches.\n\n\"diff-insert=\"\nSGR substring for inserted lines within generated patches.\n\n\"type-diff=\"\nSGR substring for highlighting mismatching types within template arguments in the C++\nfrontend.\n"
                },
                {
                    "name": "-fdiagnostics-urls[=_",
                    "content": "Use   escape   sequences   to   embed   URLs   in   diagnostics.    For   example,   when\n-fdiagnostics-show-option emits  text  showing  the  command-line  option  controlling  a\ndiagnostic, embed a URL for documentation of that option.\n\nWHEN  is  never,  always, or auto.  auto makes GCC use URL escape sequences only when the\nstandard error is a terminal, and when not executing in an emacs shell or  any  graphical\nterminal which is known to be incompatible with this feature, see below.\n\nThe  default depends on how the compiler has been configured.  It can be any of the above\nWHEN options.\n\nGCC can also be configured (via  the  --with-diagnostics-urls=auto-if-env  configure-time\noption)  so  that  the  default  is  affected  by  environment  variables.   Under such a\nconfiguration, GCC defaults to using auto if either  GCCURLS  or  TERMURLS  environment\nvariables  are  present  and  non-empty  in  the environment of the compiler, or never if\nneither are.\n\nHowever,  even  with  -fdiagnostics-urls=always  the  behavior  is  dependent  on   those\nenvironment  variables:  If  GCCURLS  is  set  to  empty  or  no,  do  not embed URLs in\ndiagnostics.  If set to st, URLs use ST escape sequences.  If set to  bel,  the  default,\nURLs  use  BEL  escape  sequences.   Any  other  non-empty value enables the feature.  If\nGCCURLS is not set, use TERMURLS as a fallback.  Note: ST is an ANSI  escape  sequence,\nstring  terminator  ESC  \\,  BEL is an ASCII character, CTRL-G that usually sounds like a\nbeep.\n\nAt this time GCC tries to detect also a few terminals that are known to not implement the\nURL feature, and have bugs or at least had bugs in some versions that are still  in  use,\nwhere  the  URL  escapes are likely to misbehave, i.e. print garbage on the screen.  That\nlist is currently xfce4-terminal, certain known to be buggy gnome-terminal versions,  the\nlinux console, and mingw.  This check can be skipped with the -fdiagnostics-urls=always.\n"
                },
                {
                    "name": "-fno-diagnostics-show-option",
                    "content": "By default, each diagnostic emitted includes text indicating the command-line option that\ndirectly  controls  the  diagnostic  (if  such  an  option  is  known  to  the diagnostic\nmachinery).  Specifying the -fno-diagnostics-show-option flag suppresses that behavior.\n"
                },
                {
                    "name": "-fno-diagnostics-show-caret",
                    "content": "By default, each diagnostic emitted includes the original  source  line  and  a  caret  ^\nindicating  the  column.   This  option  suppresses this information.  The source line is\ntruncated to n characters, if the -fmessage-length=n option is given.  When the output is\ndone to the terminal, the width is limited to the width given by the COLUMNS  environment\nvariable or, if not set, to the terminal width.\n"
                },
                {
                    "name": "-fno-diagnostics-show-labels",
                    "content": "By  default,  when  printing  source code (via -fdiagnostics-show-caret), diagnostics can\nlabel ranges of source code with pertinent information, such as the types of expressions:\n\nprintf (\"foo %s bar\", longi + longj);\n~^       ~~~~~~~~~~~~~~~\n|              |\nchar *         long int\n\nThis option suppresses the printing of these labels (in the example above,  the  vertical\nbars and the \"char *\" and \"long int\" text).\n"
                },
                {
                    "name": "-fno-diagnostics-show-cwe",
                    "content": "Diagnostic messages can optionally have an associated\nCWE  (\"https://cwe.mitre.org/index.html\")  identifier.   GCC  itself  only provides such\nmetadata  for  some  of  the  -fanalyzer  diagnostics.   GCC  plugins  may  also  provide\ndiagnostics  with  such metadata.  By default, if this information is present, it will be\nprinted with the diagnostic.  This option suppresses the printing of this metadata.\n"
                },
                {
                    "name": "-fno-diagnostics-show-rules",
                    "content": "Diagnostic messages can optionally have rules associated with them, such as from a coding\nstandard, or a specification.  GCC itself does not do this for any  of  its  diagnostics,\nbut  plugins  may  do so.  By default, if this information is present, it will be printed\nwith the diagnostic.  This option suppresses the printing of this metadata.\n"
                },
                {
                    "name": "-fno-diagnostics-show-line-numbers",
                    "content": "By default, when printing source code (via -fdiagnostics-show-caret), a  left  margin  is\nprinted, showing line numbers.  This option suppresses this left margin.\n"
                },
                {
                    "name": "-fdiagnostics-minimum-margin-width=_",
                    "content": "This   option   controls   the   minimum   width   of   the   left   margin   printed  by\n-fdiagnostics-show-line-numbers.  It defaults to 6.\n"
                },
                {
                    "name": "-fdiagnostics-parseable-fixits",
                    "content": "Emit fix-it hints in a machine-parseable format, suitable for consumption by  IDEs.   For\neach  fix-it,  a  line  will  be printed after the relevant diagnostic, starting with the\nstring \"fix-it:\".  For example:\n\nfix-it:\"test.c\":{45:3-45:21}:\"gtkwidgetshowall\"\n\nThe location is expressed as a half-open range, expressed as a count of  bytes,  starting\nat byte 1 for the initial column.  In the above example, bytes 3 through 20 of line 45 of\n\"test.c\" are to be replaced with the given string:\n\n00000000011111111112222222222\n12345678901234567890123456789\ngtkwidgetshowall (dlg);\n^^^^^^^^^^^^^^^^^^\ngtkwidgetshowall\n\nThe  filename  and  replacement  string escape backslash as \"\\\\\", tab as \"\\t\", newline as\n\"\\n\", double quotes as \"\\\"\", non-printable characters as  octal  (e.g.  vertical  tab  as\n\"\\013\").\n\nAn  empty  replacement  string indicates that the given range is to be removed.  An empty\nrange (e.g. \"45:3-45:3\") indicates that the  string  is  to  be  inserted  at  the  given\nposition.\n"
                },
                {
                    "name": "-fdiagnostics-generate-patch",
                    "content": "Print  fix-it  hints to stderr in unified diff format, after any diagnostics are printed.\nFor example:\n\n--- test.c\n+++ test.c\n@ -42,5 +42,5 @\n\nvoid showcb(GtkDialog *dlg)\n{\n-  gtkwidgetshowall(dlg);\n+  gtkwidgetshowall(dlg);\n}\n\nThe diff may or may not be colorized, following the same rules as  for  diagnostics  (see\n-fdiagnostics-color).\n"
                },
                {
                    "name": "-fdiagnostics-show-template-tree",
                    "content": "In  the  C++ frontend, when printing diagnostics showing mismatching template types, such\nas:\n\ncould not convert 'std::map<int, std::vector<double> >()'\nfrom 'map<[...],vector<double>>' to 'map<[...],vector<float>>\n\nthe -fdiagnostics-show-template-tree flag enables printing a tree-like structure  showing\nthe common and differing parts of the types, such as:\n\nmap<\n[...],\nvector<\n[double != float]>>\n\nThe parts that differ are highlighted with color (\"double\" and \"float\" in this case).\n"
                },
                {
                    "name": "-fno-elide-type",
                    "content": "By  default  when the C++ frontend prints diagnostics showing mismatching template types,\ncommon parts of the types are printed as \"[...]\" to  simplify  the  error  message.   For\nexample:\n\ncould not convert 'std::map<int, std::vector<double> >()'\nfrom 'map<[...],vector<double>>' to 'map<[...],vector<float>>\n\nSpecifying the -fno-elide-type flag suppresses that behavior.  This flag also affects the\noutput of the -fdiagnostics-show-template-tree flag.\n"
                },
                {
                    "name": "-fdiagnostics-path-format=_",
                    "content": "Specify  how  to print paths of control-flow events for diagnostics that have such a path\nassociated with them.\n\nKIND is none, separate-events, or inline-events, the default.\n\nnone means to not print diagnostic paths.\n\nseparate-events means to print a separate \"note\" diagnostic for  each  event  within  the\ndiagnostic.  For example:\n\ntest.c:29:5: error: passing NULL as argument 1 to 'PyListAppend' which requires a non-NULL parameter\ntest.c:25:10: note: (1) when 'PyListNew' fails, returning NULL\ntest.c:27:3: note: (2) when 'i < count'\ntest.c:29:5: note: (3) when calling 'PyListAppend', passing NULL from (1) as argument 1\n\ninline-events  means  to  print  the  events  \"inline\" within the source code.  This view\nattempts to consolidate the events into runs of sufficiently-close events, printing  them\nas labelled ranges within the source.\n\nFor example, the same events as above might be printed as:\n\n'test': events 1-3\n|\n|   25 |   list = PyListNew(0);\n|      |          ^~~~~~~~~~~~~\n|      |          |\n|      |          (1) when 'PyListNew' fails, returning NULL\n|   26 |\n|   27 |   for (i = 0; i < count; i++) {\n|      |   ~~~\n|      |   |\n|      |   (2) when 'i < count'\n|   28 |     item = PyLongFromLong(random());\n|   29 |     PyListAppend(list, item);\n|      |     ~~~~~~~~~~~~~~~~~~~~~~~~~\n|      |     |\n|      |     (3) when calling 'PyListAppend', passing NULL from (1) as argument 1\n|\n\nInterprocedural  control  flow  is shown by grouping the events by stack frame, and using\nindentation to show how stack frames are nested, pushed, and popped.\n\nFor example:\n\n'test': events 1-2\n|\n|  133 | {\n|      | ^\n|      | |\n|      | (1) entering 'test'\n|  134 |   boxedint *obj = makeboxedint (i);\n|      |                    ~~~~~~~~~~~~~~~~~~\n|      |                    |\n|      |                    (2) calling 'makeboxedint'\n|\n+--> 'makeboxedint': events 3-4\n|\n|  120 | {\n|      | ^\n|      | |\n|      | (3) entering 'makeboxedint'\n|  121 |   boxedint *result = (boxedint *)wrappedmalloc (sizeof (boxedint));\n|      |                                    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n|      |                                    |\n|      |                                    (4) calling 'wrappedmalloc'\n|\n+--> 'wrappedmalloc': events 5-6\n|\n|    7 | {\n|      | ^\n|      | |\n|      | (5) entering 'wrappedmalloc'\n|    8 |   return malloc (size);\n|      |          ~~~~~~~~~~~~~\n|      |          |\n|      |          (6) calling 'malloc'\n|\n<-------------+\n|\n'test': event 7\n|\n|  138 |   freeboxedint (obj);\n|      |   ^~~~~~~~~~~~~~~~~~~~\n|      |   |\n|      |   (7) calling 'freeboxedint'\n|\n(etc)\n"
                },
                {
                    "name": "-fdiagnostics-show-path-depths",
                    "content": "This option provides additional information when printing control-flow  paths  associated\nwith a diagnostic.\n\nIf this is option is provided then the stack depth will be printed for each run of events\nwithin       -fdiagnostics-path-format=inline-events.        If       provided       with\n-fdiagnostics-path-format=separate-events, then the stack depth and function  declaration\nwill be appended when printing each event.\n\nThis  is  intended  for  use  by  GCC  developers  and  plugin  developers when debugging\ndiagnostics that report interprocedural control flow.\n"
                },
                {
                    "name": "-fno-show-column",
                    "content": "Do not print column numbers in diagnostics.  This may be  necessary  if  diagnostics  are\nbeing scanned by a program that does not understand the column numbers, such as dejagnu.\n"
                },
                {
                    "name": "-fdiagnostics-column-unit=_",
                    "content": "Select  the  units  for  the column number.  This affects traditional diagnostics (in the\nabsence of -fno-show-column), as well as JSON format diagnostics if requested.\n\nThe default UNIT, display, considers the number  of  display  columns  occupied  by  each\ncharacter.  This may be larger than the number of bytes required to encode the character,\nin the case of tab characters, or it may be smaller, in the case of multibyte characters.\nFor  example, the character \"GREEK SMALL LETTER PI (U+03C0)\" occupies one display column,\nand its  UTF-8  encoding  requires  two  bytes;  the  character  \"SLIGHTLY  SMILING  FACE\n(U+1F642)\" occupies two display columns, and its UTF-8 encoding requires four bytes.\n\nSetting UNIT to byte changes the column number to the raw byte count in all cases, as was\ntraditionally output by GCC prior to version 11.1.0.\n"
                },
                {
                    "name": "-fdiagnostics-column-origin=_",
                    "content": "Select  the  origin  for  column  numbers,  i.e.  the column number assigned to the first\ncolumn.  The default value of 1 corresponds to traditional GCC behavior and  to  the  GNU\nstyle  guide.   Some  utilities  may perform better with an origin of 0; any non-negative\nvalue may be specified.\n"
                },
                {
                    "name": "-fdiagnostics-escape-format=_",
                    "content": "When GCC prints pertinent source lines for a diagnostic it normally attempts to print the\nsource bytes directly.  However, some diagnostics relate to encoding issues in the source\nfile, such as malformed UTF-8, or issues with Unicode normalization.   These  diagnostics\nare  flagged  so  that  GCC  will escape bytes that are not printable ASCII when printing\ntheir pertinent source lines.\n\nThis option controls how such bytes should be escaped.\n\nThe default FORMAT, unicode displays Unicode characters that are not printable  ASCII  in\nthe  form  <U+XXXX>,  and  bytes  that  do not correspond to a Unicode character validly-\nencoded in UTF-8-encoded will be displayed as hexadecimal in the form <XX>.\n\nFor example, a source line containing the string before followed by the Unicode character\nU+03C0 (\"GREEK SMALL LETTER PI\", with UTF-8 encoding 0xCF 0x80) followed by the byte 0xBF\n(a stray UTF-8 trailing byte), followed by the string after will be printed  for  such  a\ndiagnostic as:\n\nbefore<U+03C0><BF>after\n\nSetting FORMAT to bytes will display all non-printable-ASCII bytes in the form <XX>, thus\nshowing  the underlying encoding of non-ASCII Unicode characters.  For the example above,\nthe following will be printed:\n\nbefore<CF><80><BF>after\n"
                },
                {
                    "name": "-fdiagnostics-format=_",
                    "content": "Select a different format for printing diagnostics.  FORMAT is text, sarif-stderr, sarif-\nfile, json, json-stderr, or json-file.\n\nThe default is text.\n\nThe sarif-stderr and sarif-file formats both emit  diagnostics  in  SARIF  Version  2.1.0\nformat, either to stderr, or to a file named source.sarif, respectively.\n\nThe  json format is a synonym for json-stderr.  The json-stderr and json-file formats are\nidentical, apart from where the JSON is emitted to - with the former, the JSON is emitted\nto stderr, whereas with json-file it is written to source.gcc.json.\n\nThe emitted JSON consists of a top-level JSON array containing JSON objects  representing\nthe diagnostics.  The JSON is emitted as one line, without formatting; the examples below\nhave been formatted for clarity.\n\nDiagnostics can have child diagnostics.  For example, this error and note:\n\nmisleading-indentation.c:15:3: warning: this 'if' clause does not\nguard... [-Wmisleading-indentation]\n15 |   if (flag)\n|   ^~\nmisleading-indentation.c:17:5: note: ...this statement, but the latter\nis misleadingly indented as if it were guarded by the 'if'\n17 |     y = 2;\n|     ^\n\nmight be printed in JSON form (after formatting) like this:\n\n[\n{\n\"kind\": \"warning\",\n\"locations\": [\n{\n\"caret\": {\n\"display-column\": 3,\n\"byte-column\": 3,\n\"column\": 3,\n\"file\": \"misleading-indentation.c\",\n\"line\": 15\n},\n\"finish\": {\n\"display-column\": 4,\n\"byte-column\": 4,\n\"column\": 4,\n\"file\": \"misleading-indentation.c\",\n\"line\": 15\n}\n}\n],\n\"message\": \"this \\u2018if\\u2019 clause does not guard...\",\n\"option\": \"-Wmisleading-indentation\",\n\"optionurl\": \"https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#index-Wmisleading-indentation\",\n\"children\": [\n{\n\"kind\": \"note\",\n\"locations\": [\n{\n\"caret\": {\n\"display-column\": 5,\n\"byte-column\": 5,\n\"column\": 5,\n\"file\": \"misleading-indentation.c\",\n\"line\": 17\n}\n}\n],\n\"escape-source\": false,\n\"message\": \"...this statement, but the latter is ...\"\n}\n]\n\"escape-source\": false,\n\"column-origin\": 1,\n}\n]\n\nwhere the \"note\" is a child of the \"warning\".\n\nA  diagnostic  has  a  \"kind\".   If  this  is  \"warning\",  then  there is an \"option\" key\ndescribing the command-line option controlling the warning.\n\nA diagnostic can contain zero or more locations.  Each location has an  optional  \"label\"\nstring  and  up to three positions within it: a \"caret\" position and optional \"start\" and\n\"finish\" positions.  A position is described by a \"file\" name, a \"line\" number, and three\nnumbers indicating a column position:\n\n*   \"display-column\"  counts  display  columns,  accounting  for   tabs   and   multibyte\ncharacters.\n\n*   \"byte-column\" counts raw bytes.\n\n*   \"column\"   is   equal   to   one   of   the   previous   two,   as  dictated  by  the\n-fdiagnostics-column-unit option.\n\nAll three columns are relative to the origin  specified  by  -fdiagnostics-column-origin,\nwhich  is  typically equal to 1 but may be set, for instance, to 0 for compatibility with\nother utilities that number columns from 0.  The column origin is recorded  in  the  JSON\noutput  in  the  \"column-origin\"  tag.  In the remaining examples below, the extra column\nnumber outputs have been omitted for brevity.\n\nFor example, this error:\n\nbad-binary-ops.c:64:23: error: invalid operands to binary + (have 'S' {aka\n'struct s'} and 'T' {aka 'struct t'})\n64 |   return callee4a () + callee4b ();\n|          ~~~~~~~~~~~~ ^ ~~~~~~~~~~~~\n|          |              |\n|          |              T {aka struct t}\n|          S {aka struct s}\n\nhas three locations.  Its primary location is at the \"+\" token at column 23.  It has  two\nsecondary  locations,  describing  the left and right-hand sides of the expression, which\nhave labels.  It might be printed in JSON form as:\n\n{\n\"children\": [],\n\"kind\": \"error\",\n\"locations\": [\n{\n\"caret\": {\n\"column\": 23, \"file\": \"bad-binary-ops.c\", \"line\": 64\n}\n},\n{\n\"caret\": {\n\"column\": 10, \"file\": \"bad-binary-ops.c\", \"line\": 64\n},\n\"finish\": {\n\"column\": 21, \"file\": \"bad-binary-ops.c\", \"line\": 64\n},\n\"label\": \"S {aka struct s}\"\n},\n{\n\"caret\": {\n\"column\": 25, \"file\": \"bad-binary-ops.c\", \"line\": 64\n},\n\"finish\": {\n\"column\": 36, \"file\": \"bad-binary-ops.c\", \"line\": 64\n},\n\"label\": \"T {aka struct t}\"\n}\n],\n\"escape-source\": false,\n\"message\": \"invalid operands to binary + ...\"\n}\n\nIf a diagnostic contains fix-it hints, it has a \"fixits\" array, consisting  of  half-open\nintervals,  similar  to  the output of -fdiagnostics-parseable-fixits.  For example, this\ndiagnostic with a replacement fix-it hint:\n\ndemo.c:8:15: error: 'struct s' has no member named 'colour'; did you\nmean 'color'?\n8 |   return ptr->colour;\n|               ^~~~~~\n|               color\n\nmight be printed in JSON form as:\n\n{\n\"children\": [],\n\"fixits\": [\n{\n\"next\": {\n\"column\": 21,\n\"file\": \"demo.c\",\n\"line\": 8\n},\n\"start\": {\n\"column\": 15,\n\"file\": \"demo.c\",\n\"line\": 8\n},\n\"string\": \"color\"\n}\n],\n\"kind\": \"error\",\n\"locations\": [\n{\n\"caret\": {\n\"column\": 15,\n\"file\": \"demo.c\",\n\"line\": 8\n},\n\"finish\": {\n\"column\": 20,\n\"file\": \"demo.c\",\n\"line\": 8\n}\n}\n],\n\"escape-source\": false,\n\"message\": \"\\u2018struct s\\u2019 has no member named ...\"\n}\n\nwhere the fix-it hint suggests replacing the text from \"start\" up to  but  not  including\n\"next\"  with  \"string\"'s value.  Deletions are expressed via an empty value for \"string\",\ninsertions by having \"start\" equal \"next\".\n\nIf the diagnostic has a path of control-flow events associated with it, it has  a  \"path\"\narray  of objects representing the events.  Each event object has a \"description\" string,\na \"location\" object, along with a \"function\" string and a \"depth\" number for representing\ninterprocedural paths.  The \"function\" represents the current function at that event, and\nthe \"depth\" represents the stack depth relative to some baseline: the  higher,  the  more\nframes are within the stack.\n\nFor  example, the intraprocedural example shown for -fdiagnostics-path-format= might have\nthis JSON for its path:\n\n\"path\": [\n{\n\"depth\": 0,\n\"description\": \"when 'PyListNew' fails, returning NULL\",\n\"function\": \"test\",\n\"location\": {\n\"column\": 10,\n\"file\": \"test.c\",\n\"line\": 25\n}\n},\n{\n\"depth\": 0,\n\"description\": \"when 'i < count'\",\n\"function\": \"test\",\n\"location\": {\n\"column\": 3,\n\"file\": \"test.c\",\n\"line\": 27\n}\n},\n{\n\"depth\": 0,\n\"description\": \"when calling 'PyListAppend', passing NULL from (1) as argument 1\",\n\"function\": \"test\",\n\"location\": {\n\"column\": 5,\n\"file\": \"test.c\",\n\"line\": 29\n}\n}\n]\n\nDiagnostics have a boolean attribute \"escape-source\",  hinting  whether  non-ASCII  bytes\nshould  be  escaped  when  printing  the  pertinent  lines  of  source  code  (\"true\" for\ndiagnostics involving source encoding issues).\n"
                },
                {
                    "name": "Options to Request or Suppress Warnings",
                    "content": "Warnings are diagnostic messages that report constructions that are not inherently  erroneous\nbut that are risky or suggest there may have been an error.\n\nThe  following  language-independent  options do not enable specific warnings but control the\nkinds of diagnostics produced by GCC.\n"
                },
                {
                    "name": "-fsyntax-only",
                    "content": "Check the code for syntax errors, but don't do anything beyond that.\n"
                },
                {
                    "name": "-fmax-errors=_",
                    "content": "Limits the maximum number of error messages to n, at which point  GCC  bails  out  rather\nthan  attempting  to continue processing the source code.  If n is 0 (the default), there\nis no limit on the  number  of  error  messages  produced.   If  -Wfatal-errors  is  also\nspecified, then -Wfatal-errors takes precedence over this option.\n"
                },
                {
                    "name": "-w",
                    "content": "",
                    "flag": "-w"
                },
                {
                    "name": "-Werror",
                    "content": "Make all warnings into errors.\n"
                },
                {
                    "name": "-Werror=",
                    "content": "Make  the  specified warning into an error.  The specifier for a warning is appended; for\nexample -Werror=switch turns the warnings  controlled  by  -Wswitch  into  errors.   This\nswitch  takes  a  negative  form, to be used to negate -Werror for specific warnings; for\nexample -Wno-error=switch makes -Wswitch warnings not be errors, even when -Werror is  in\neffect.\n\nThe  warning  message for each controllable warning includes the option that controls the\nwarning.  That option can then be used with -Werror= and -Wno-error= as described  above.\n(Printing   of   the   option   in   the  warning  message  can  be  disabled  using  the\n-fno-diagnostics-show-option flag.)\n\nNote that specifying -Werror=foo automatically implies  -Wfoo.   However,  -Wno-error=foo\ndoes not imply anything.\n"
                },
                {
                    "name": "-Wfatal-errors",
                    "content": "This  option  causes the compiler to abort compilation on the first error occurred rather\nthan trying to keep going and printing further error messages.\n\nYou can request many specific warnings with options beginning with -W, for example -Wimplicit\nto request warnings on implicit declarations.  Each of these specific  warning  options  also\nhas  a  negative form beginning -Wno- to turn off warnings; for example, -Wno-implicit.  This\nmanual lists only one of the two forms, whichever is not the default.  For further  language-\nspecific  options also refer to C++ Dialect Options and Objective-C and Objective-C++ Dialect\nOptions.  Additional warnings can be produced by enabling the static analyzer;\n\nSome options, such as -Wall and -Wextra, turn on other options, such as -Wunused,  which  may\nturn on further options, such as -Wunused-value. The combined effect of positive and negative\nforms  is  that more specific options have priority over less specific ones, independently of\ntheir position in the command-line. For options of the same specificity, the last  one  takes\neffect. Options enabled or disabled via pragmas take effect as if they appeared at the end of\nthe command-line.\n\nWhen  an  unrecognized  warning  option  is  requested (e.g., -Wunknown-warning), GCC emits a\ndiagnostic stating that the option is not recognized.  However, if the -Wno-  form  is  used,\nthe behavior is slightly different: no diagnostic is produced for -Wno-unknown-warning unless\nother  diagnostics  are  being  produced.   This allows the use of new -Wno- options with old\ncompilers, but if something goes wrong, the compiler warns that  an  unrecognized  option  is\npresent.\n\nThe  effectiveness  of some warnings depends on optimizations also being enabled. For example"
                },
                {
                    "name": "-Wsuggest-final-types",
                    "content": "other  warnings  may not be issued at all unless optimization is enabled.  While optimization\nin general improves the efficacy of control and data flow sensitive warnings, in  some  cases\nit may also cause false positives.\n"
                },
                {
                    "name": "-Wpedantic",
                    "content": ""
                },
                {
                    "name": "-pedantic",
                    "content": "Issue all the warnings demanded by strict ISO C and ISO C++; reject all programs that use\nforbidden  extensions, and some other programs that do not follow ISO C and ISO C++.  For\nISO C, follows the version of the ISO C standard specified by any -std option used.\n\nValid ISO C and ISO C++ programs should compile properly  with  or  without  this  option\n(though  a rare few require -ansi or a -std option specifying the required version of ISO\nC).  However, without this option, certain GNU  extensions  and  traditional  C  and  C++\nfeatures are supported as well.  With this option, they are rejected.\n\n-Wpedantic  does not cause warning messages for use of the alternate keywords whose names\nbegin and end with .  This alternate format can also be used to  disable  warnings  for\nnon-ISO  intN  types,  i.e.  intN.   Pedantic  warnings  are  also  disabled in the\nexpression that follows \"extension\".  However, only system header  files  should  use\nthese escape routes; application programs should avoid them.\n\nSome  users  try  to use -Wpedantic to check programs for strict ISO C conformance.  They\nsoon find that it does not do quite what they want: it finds some non-ISO practices,  but\nnot  all---only  those  for  which ISO C requires a diagnostic, and some others for which\ndiagnostics have been added.\n\nA feature to report any failure to conform to ISO C might be useful  in  some  instances,\nbut  would  require  considerable  additional  work  and  would  be  quite different from\n-Wpedantic.  We don't have plans to support such a feature in the near future.\n\nWhere the standard specified with -std represents a GNU extended dialect of  C,  such  as\ngnu90 or gnu99, there is a corresponding base standard, the version of ISO C on which the\nGNU  extended  dialect  is  based.   Warnings  from  -Wpedantic  are given where they are\nrequired by the base standard.  (It does not make sense for such  warnings  to  be  given\nonly  for  features  not  in  the  specified  GNU  C dialect, since by definition the GNU\ndialects of C include all features the compiler supports with the given option, and there\nwould be nothing to warn about.)\n"
                },
                {
                    "name": "-pedantic-errors",
                    "content": "Give an error whenever the base standard (see -Wpedantic) requires a diagnostic, in  some\ncases  where  there is undefined behavior at compile-time and in some other cases that do\nnot prevent compilation of programs that are valid according to the standard. This is not\nequivalent to -Werror=pedantic, since there are errors enabled by  this  option  and  not\nenabled by the latter and vice versa.\n"
                },
                {
                    "name": "-Wall",
                    "content": "This  enables all the warnings about constructions that some users consider questionable,\nand that are easy to avoid (or modify to prevent the warning), even in  conjunction  with\nmacros.   This  also  enables  some  language-specific  warnings described in C++ Dialect\nOptions and Objective-C and Objective-C++ Dialect Options.\n\n-Wall turns on the following warning flags:\n\n-Waddress -Warray-bounds=1 (only with -O2)  -Warray-compare  -Warray-parameter=2  (C  and\nObjective-C   only)   -Wbool-compare   -Wbool-operation   -Wc++11-compat   -Wc++14-compat\n-Wcatch-value    (C++    and    Objective-C++    only)    -Wchar-subscripts     -Wcomment\n-Wdangling-pointer=2  -Wduplicate-decl-specifier  (C and Objective-C only) -Wenum-compare\n(in C/ObjC; this is on by default in C++) -Wenum-int-mismatch (C  and  Objective-C  only)\n-Wformat  -Wformat-overflow  -Wformat-truncation  -Wint-in-bool-context -Wimplicit (C and\nObjective-C only) -Wimplicit-int (C and Objective-C only) -Wimplicit-function-declaration\n(C and Objective-C only) -Winit-self  (only  for  C++)  -Wlogical-not-parentheses  -Wmain\n(only  for  C/ObjC  and  unless  -ffreestanding)  -Wmaybe-uninitialized -Wmemset-elt-size\n-Wmemset-transposed-args -Wmisleading-indentation (only for  C/C++)  -Wmismatched-dealloc\n-Wmismatched-new-delete  (only for C/C++) -Wmissing-attributes -Wmissing-braces (only for\nC/ObjC) -Wmultistatement-macros -Wnarrowing (only for  C++)  -Wnonnull  -Wnonnull-compare\n-Wopenmp-simd    -Wparentheses   -Wpessimizing-move   (only   for   C++)   -Wpointer-sign\n-Wrange-loop-construct (only for  C++)  -Wreorder  -Wrestrict  -Wreturn-type  -Wself-move\n(only   for   C++)  -Wsequence-point  -Wsign-compare  (only  in  C++)  -Wsizeof-array-div\n-Wsizeof-pointer-div  -Wsizeof-pointer-memaccess  -Wstrict-aliasing   -Wstrict-overflow=1\n-Wswitch    -Wtautological-compare    -Wtrigraphs    -Wuninitialized    -Wunknown-pragmas\n-Wunused-function  -Wunused-label  -Wunused-value  -Wunused-variable   -Wuse-after-free=2\n-Wvla-parameter (C and Objective-C only) -Wvolatile-register-var -Wzero-length-bounds\n\nNote  that  some  warning  flags  are  not  implied  by  -Wall.   Some of them warn about\nconstructions that users generally do not consider questionable, but  which  occasionally\nyou  might  wish to check for; others warn about constructions that are necessary or hard\nto avoid in some cases, and there is no simple way to modify the  code  to  suppress  the\nwarning.  Some  of  them  are  enabled  by  -Wextra  but  many  of  them  must be enabled\nindividually.\n"
                },
                {
                    "name": "-Wextra",
                    "content": "This enables some extra warning flags that are not enabled by -Wall. (This option used to\nbe called  -W.   The  older  name  is  still  supported,  but  the  newer  name  is  more\ndescriptive.)\n\n-Wclobbered  -Wcast-function-type  -Wdangling-reference (C++ only) -Wdeprecated-copy (C++\nonly)     -Wempty-body     -Wenum-conversion      (C      only)      -Wignored-qualifiers\n-Wimplicit-fallthrough=3  -Wmissing-field-initializers  -Wmissing-parameter-type (C only)\n-Wold-style-declaration (C only) -Woverride-init -Wsign-compare (C only) -Wstring-compare\n-Wredundant-move (only for C++) -Wtype-limits -Wuninitialized -Wshift-negative-value  (in\nC++11  to  C++17  and  in C99 and newer) -Wunused-parameter (only with -Wunused or -Wall)\n-Wunused-but-set-parameter (only with -Wunused or -Wall)\n\nThe option -Wextra also prints warning messages for the following cases:\n\n*   A pointer is compared against integer zero with \"<\", \"<=\", \">\", or \">=\".\n\n*   (C++  only)  An  enumerator  and  a  non-enumerator  both  appear  in  a  conditional\nexpression.\n\n*   (C++ only) Ambiguous virtual bases.\n\n*   (C++ only) Subscripting an array that has been declared \"register\".\n\n*   (C++ only) Taking the address of a variable that has been declared \"register\".\n\n*   (C++  only)  A  base  class  is  not initialized in the copy constructor of a derived\nclass.\n"
                },
                {
                    "name": "-Wabi",
                    "content": "Warn about code affected by ABI changes.  This includes code that may not  be  compatible\nwith the vendor-neutral C++ ABI as well as the psABI for the particular target.\n\nSince  G++ now defaults to updating the ABI with each major release, normally -Wabi warns\nonly about C++ ABI compatibility problems if there is a check added later  in  a  release\nseries  for  an  ABI  issue discovered since the initial release.  -Wabi warns about more\nthings if an older ABI version is selected (with -fabi-version=n).\n\n-Wabi can  also  be  used  with  an  explicit  version  number  to  warn  about  C++  ABI\ncompatibility  with  a particular -fabi-version level, e.g. -Wabi=2 to warn about changes\nrelative to -fabi-version=2.\n\nIf an explicit version number is provided and -fabi-compat-version is not specified,  the\nversion  number  from  this  option  is  used  for compatibility aliases.  If no explicit\nversion number is provided with this option, but -fabi-compat-version is specified,  that\nversion number is used for C++ ABI warnings.\n\nAlthough  an  effort  has been made to warn about all such cases, there are probably some\ncases that are not warned about, even though G++ is generating incompatible code.   There\nmay  also  be  cases where warnings are emitted even though the code that is generated is\ncompatible.\n\nYou should rewrite your code to avoid these warnings if you are concerned about the  fact\nthat  code  generated  by  G++  may not be binary compatible with code generated by other\ncompilers.\n\nKnown incompatibilities in -fabi-version=2 (which was the default from GCC  3.4  to  4.9)\ninclude:\n\n*   A  template  with  a  non-type  template  parameter  of  reference  type  was mangled\nincorrectly:\n\nextern int N;\ntemplate <int &> struct S {};\nvoid n (S<N>) {2}\n\nThis was fixed in -fabi-version=3.\n\n*   SIMD vector types declared using \"attribute ((vectorsize))\" were mangled in a non-\nstandard way that does not allow for  overloading  of  functions  taking  vectors  of\ndifferent sizes.\n\nThe mangling was changed in -fabi-version=4.\n\n*   \"attribute   ((const))\"  and  \"noreturn\"  were  mangled  as  type  qualifiers,  and\n\"decltype\" of a plain declaration was folded away.\n\nThese mangling issues were fixed in -fabi-version=5.\n\n*   Scoped enumerators passed as arguments to  a  variadic  function  are  promoted  like\nunscoped  enumerators,  causing  \"vaarg\" to complain.  On most targets this does not\nactually affect the parameter passing ABI, as there is no way  to  pass  an  argument\nsmaller than \"int\".\n\nAlso,  the  ABI  changed  the  mangling  of  template  argument  packs, \"constcast\",\n\"staticcast\", prefix increment/decrement, and a  class  scope  function  used  as  a\ntemplate argument.\n\nThese issues were corrected in -fabi-version=6.\n\n*   Lambdas  in  default argument scope were mangled incorrectly, and the ABI changed the\nmangling of \"nullptrt\".\n\nThese issues were corrected in -fabi-version=7.\n\n*   When mangling a function type with function-cv-qualifiers, the un-qualified  function\ntype was incorrectly treated as a substitution candidate.\n\nThis was fixed in -fabi-version=8, the default for GCC 5.1.\n\n*   decltype(nullptr)  incorrectly  had an alignment of 1, leading to unaligned accesses.\nNote that this did not affect the ABI of a function with a \"nullptrt\" parameter,  as\nparameters have a minimum alignment.\n\nThis was fixed in -fabi-version=9, the default for GCC 5.2.\n\n*   Target-specific  attributes  that affect the identity of a type, such as ia32 calling\nconventions on a function type (stdcall, regparm, etc.), did not affect  the  mangled\nname,  leading  to  name  collisions  when  function  pointers  were used as template\narguments.\n\nThis was fixed in -fabi-version=10, the default for GCC 6.1.\n\nThis option also enables warnings about psABI-related changes.  The known  psABI  changes\nat this point include:\n\n*   For  SysV/x86-64, unions with \"long double\" members are passed in memory as specified\nin psABI.  Prior to GCC 4.4, this was not the case.  For example:\n\nunion U {\nlong double ld;\nint i;\n};\n\n\"union U\" is now always passed in memory.\n"
                },
                {
                    "name": "-Wno-changes-meaning",
                    "content": "C++ requires that unqualified uses of a name within a class have the same meaning in  the\ncomplete scope of the class, so declaring the name after using it is ill-formed:\n\nstruct A;\nstruct B1 { A a; typedef A A; }; // warning, 'A' changes meaning\nstruct B2 { A a; struct A { }; }; // error, 'A' changes meaning\n\nBy  default,  the  B1  case  is only a warning because the two declarations have the same\ntype,  while  the  B2  case  is  an  error.   Both  diagnostics  can  be  disabled   with\n-Wno-changes-meaning.   Alternately,  the  error  case  can  be reduced to a warning with\n-Wno-error=changes-meaning or -fpermissive.\n\nBoth diagnostics are also suppressed by -fms-extensions.\n"
                },
                {
                    "name": "-Wchar-subscripts",
                    "content": "Warn if an array subscript has type  \"char\".   This  is  a  common  cause  of  error,  as\nprogrammers  often  forget  that  this  type is signed on some machines.  This warning is\nenabled by -Wall.\n"
                },
                {
                    "name": "-Wno-coverage-mismatch",
                    "content": "Warn if feedback profiles do not match when using the -fprofile-use option.  If a  source\nfile  is  changed  between  compiling with -fprofile-generate and with -fprofile-use, the\nfiles with the profile feedback can fail to match the source file and GCC cannot use  the\nprofile  feedback  information.  By default, this warning is enabled and is treated as an\nerror.    -Wno-coverage-mismatch   can   be   used   to   disable    the    warning    or\n-Wno-error=coverage-mismatch  can  be used to disable the error.  Disabling the error for\nthis warning can result in poorly optimized code and is useful only in the case  of  very\nminor  changes  such  as  bug  fixes  to an existing code-base.  Completely disabling the\nwarning is not recommended.\n"
                },
                {
                    "name": "-Wno-coverage-invalid-line-number",
                    "content": "Warn in case a function ends earlier than it begins due to  an  invalid  linenum  macros.\nThe warning is emitted only with --coverage enabled.\n\nBy    default,    this    warning    is   enabled   and   is   treated   as   an   error.\n-Wno-coverage-invalid-line-number   can   be   used   to   disable   the    warning    or\n-Wno-error=coverage-invalid-line-number can be used to disable the error.\n"
                },
                {
                    "name": "-Wno-cpp",
                    "content": "Suppress warning messages emitted by \"#warning\" directives.\n"
                },
                {
                    "name": "-Wdouble-promotion",
                    "content": "Give  a  warning  when  a value of type \"float\" is implicitly promoted to \"double\".  CPUs\nwith a 32-bit \"single-precision\" floating-point unit implement \"float\" in  hardware,  but\nemulate  \"double\"  in  software.   On  such  a machine, doing computations using \"double\"\nvalues is much more expensive because of the overhead required for software emulation.\n\nIt is easy to accidentally do computations with \"double\" because floating-point  literals\nare implicitly of type \"double\".  For example, in:\n\nfloat area(float radius)\n{\nreturn 3.14159 * radius * radius;\n}\n\nthe  compiler  performs  the  entire computation with \"double\" because the floating-point\nliteral is a \"double\".\n"
                },
                {
                    "name": "-Wduplicate-decl-specifier",
                    "content": "Warn if  a  declaration  has  duplicate  \"const\",  \"volatile\",  \"restrict\"  or  \"Atomic\"\nspecifier.  This warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wformat",
                    "content": ""
                },
                {
                    "name": "-Wformat=_",
                    "content": "Check  calls to \"printf\" and \"scanf\", etc., to make sure that the arguments supplied have\ntypes appropriate to the format string specified, and that the conversions  specified  in\nthe  format string make sense.  This includes standard functions, and others specified by\nformat attributes,  in  the  \"printf\",  \"scanf\",  \"strftime\"  and  \"strfmon\"  (an  X/Open\nextension,  not  in  the C standard) families (or other target-specific families).  Which\nfunctions are checked without format attributes having  been  specified  depends  on  the\nstandard  version  selected, and such checks of functions without the attribute specified\nare disabled by -ffreestanding or -fno-builtin.\n\nThe formats are checked against the format features supported by GNU  libc  version  2.2.\nThese  include  all  ISO  C90  and C99 features, as well as features from the Single Unix\nSpecification and some BSD and GNU extensions.  Other  library  implementations  may  not\nsupport  all these features; GCC does not support warning about features that go beyond a\nparticular library's limitations.  However, if -Wpedantic is used with -Wformat, warnings\nare given about format features not  in  the  selected  standard  version  (but  not  for\n\"strfmon\" formats, since those are not in any version of the C standard).\n\n-Wformat=1\n-Wformat\nOption  -Wformat  is  equivalent  to  -Wformat=1,  and  -Wno-format  is equivalent to\n-Wformat=0.  Since -Wformat  also  checks  for  null  format  arguments  for  several\nfunctions,  -Wformat  also  implies  -Wnonnull.  Some aspects of this level of format\nchecking   can   be    disabled    by    the    options:    -Wno-format-contains-nul,\n-Wno-format-extra-args, and -Wno-format-zero-length.  -Wformat is enabled by -Wall.\n\n-Wformat=2\nEnable  -Wformat  plus  additional  format  checks.  Currently equivalent to -Wformat\n-Wformat-nonliteral -Wformat-security -Wformat-y2k.\n"
                },
                {
                    "name": "-Wno-format-contains-nul",
                    "content": "If -Wformat is specified, do not warn about format strings that contain NUL bytes.\n"
                },
                {
                    "name": "-Wno-format-extra-args",
                    "content": "If -Wformat is specified, do not warn about excess arguments to  a  \"printf\"  or  \"scanf\"\nformat function.  The C standard specifies that such arguments are ignored.\n\nWhere  the  unused arguments lie between used arguments that are specified with $ operand\nnumber specifications, normally warnings are still given, since the implementation  could\nnot  know  what  type  to pass to \"vaarg\" to skip the unused arguments.  However, in the\ncase of \"scanf\" formats, this option suppresses the warning if the unused  arguments  are\nall  pointers,  since  the  Single Unix Specification says that such unused arguments are\nallowed.\n"
                },
                {
                    "name": "-Wformat-overflow",
                    "content": ""
                },
                {
                    "name": "-Wformat-overflow=_",
                    "content": "Warn about calls to formatted input/output functions such  as  \"sprintf\"  and  \"vsprintf\"\nthat  might overflow the destination buffer.  When the exact number of bytes written by a\nformat directive cannot be determined at compile-time it is estimated based on heuristics\nthat depend on the level argument and on optimization.  While enabling optimization  will\nin most cases improve the accuracy of the warning, it may also result in false positives.\n\n-Wformat-overflow\n-Wformat-overflow=1\nLevel 1 of -Wformat-overflow enabled by -Wformat employs a conservative approach that\nwarns  only about calls that most likely overflow the buffer.  At this level, numeric\narguments to format directives with unknown values are assumed to have the  value  of\none,  and strings of unknown length to be empty.  Numeric arguments that are known to\nbe bounded to a subrange of their type, or string arguments whose output  is  bounded\neither  by  their  directive's  precision  or by a finite set of string literals, are\nassumed to take on the value within the range that  results  in  the  most  bytes  on\noutput.  For example, the call to \"sprintf\" below is diagnosed because even with both\na  and b equal to zero, the terminating NUL character ('\\0') appended by the function\nto the destination buffer will be written past its end.  Increasing the size  of  the\nbuffer  by  a  single  byte  is sufficient to avoid the warning, though it may not be\nsufficient to avoid the overflow.\n\nvoid f (int a, int b)\n{\nchar buf [13];\nsprintf (buf, \"a = %i, b = %i\\n\", a, b);\n}\n\n-Wformat-overflow=2\nLevel 2 warns also about calls that might overflow the destination  buffer  given  an\nargument  of  sufficient  length or magnitude.  At level 2, unknown numeric arguments\nare assumed to have the minimum representable value for signed types with a precision\ngreater than 1, and  the  maximum  representable  value  otherwise.   Unknown  string\narguments  whose  length  cannot  be  assumed to be bounded either by the directive's\nprecision, or by a finite set of  string  literals  they  may  evaluate  to,  or  the\ncharacter array they may point to, are assumed to be 1 character long.\n\nAt  level  2, the call in the example above is again diagnosed, but this time because\nwith a equal to a 32-bit \"INTMIN\" the first %i directive  will  write  some  of  its\ndigits beyond the end of the destination buffer.  To make the call safe regardless of\nthe values of the two variables, the size of the destination buffer must be increased\nto  at  least  34  bytes.   GCC  includes  the  minimum  size  of  the  buffer  in an\ninformational note following the warning.\n\nAn alternative to increasing the size of the destination buffer is to  constrain  the\nrange  of formatted values.  The maximum length of string arguments can be bounded by\nspecifying the precision in the format directive.  When numeric arguments  of  format\ndirectives  can  be  assumed  to be bounded by less than the precision of their type,\nchoosing an appropriate length modifier to  the  format  specifier  will  reduce  the\nrequired buffer size.  For example, if a and b in the example above can be assumed to\nbe  within  the  precision  of  the \"short int\" type then using either the %hi format\ndirective or casting the argument to \"short\" reduces the maximum required size of the\nbuffer to 24 bytes.\n\nvoid f (int a, int b)\n{\nchar buf [23];\nsprintf (buf, \"a = %hi, b = %i\\n\", a, (short)b);\n}\n"
                },
                {
                    "name": "-Wno-format-zero-length",
                    "content": "If -Wformat is specified,  do  not  warn  about  zero-length  formats.   The  C  standard\nspecifies that zero-length formats are allowed.\n"
                },
                {
                    "name": "-Wformat-nonliteral",
                    "content": "If  -Wformat  is specified, also warn if the format string is not a string literal and so\ncannot be checked, unless the format function takes its format arguments as a \"valist\".\n"
                },
                {
                    "name": "-Wformat-security",
                    "content": "If -Wformat is specified, also  warn  about  uses  of  format  functions  that  represent\npossible  security  problems.  At present, this warns about calls to \"printf\" and \"scanf\"\nfunctions where the format string is not  a  string  literal  and  there  are  no  format\narguments,  as in \"printf (foo);\".  This may be a security hole if the format string came\nfrom  untrusted  input  and  contains  %n.   (This  is  currently  a   subset   of   what\n-Wformat-nonliteral warns about, but in future warnings may be added to -Wformat-security\nthat are not included in -Wformat-nonliteral.)\n"
                },
                {
                    "name": "-Wformat-signedness",
                    "content": "If  -Wformat  is  specified, also warn if the format string requires an unsigned argument\nand the argument is signed and vice versa.\n"
                },
                {
                    "name": "-Wformat-truncation",
                    "content": ""
                },
                {
                    "name": "-Wformat-truncation=_",
                    "content": "Warn about calls to formatted input/output functions such as \"snprintf\"  and  \"vsnprintf\"\nthat  might  result  in  output  truncation.  When the exact number of bytes written by a\nformat directive cannot be determined at compile-time it is estimated based on heuristics\nthat depend on the level argument and on optimization.  While enabling optimization  will\nin most cases improve the accuracy of the warning, it may also result in false positives.\nExcept as noted otherwise, the option uses the same logic -Wformat-overflow.\n\n-Wformat-truncation\n-Wformat-truncation=1\nLevel  1  of  -Wformat-truncation enabled by -Wformat employs a conservative approach\nthat warns only about calls to bounded functions whose return  value  is  unused  and\nthat will most likely result in output truncation.\n\n-Wformat-truncation=2\nLevel  2  warns  also about calls to bounded functions whose return value is used and\nthat might result in truncation given an argument of sufficient length or magnitude.\n"
                },
                {
                    "name": "-Wformat-y2k",
                    "content": "If -Wformat is specified, also warn about \"strftime\" formats that may yield only  a  two-\ndigit year.\n"
                },
                {
                    "name": "-Wnonnull",
                    "content": "Warn  about  passing a null pointer for arguments marked as requiring a non-null value by\nthe \"nonnull\" function attribute.\n\n-Wnonnull is included in -Wall and -Wformat.  It can be disabled  with  the  -Wno-nonnull\noption.\n"
                },
                {
                    "name": "-Wnonnull-compare",
                    "content": "Warn when comparing an argument marked with the \"nonnull\" function attribute against null\ninside the function.\n\n-Wnonnull-compare is included in -Wall.  It can be disabled with the -Wno-nonnull-compare\noption.\n"
                },
                {
                    "name": "-Wnull-dereference",
                    "content": "Warn  if  the  compiler detects paths that trigger erroneous or undefined behavior due to\ndereferencing    a    null    pointer.     This    option    is    only    active    when\n-fdelete-null-pointer-checks  is  active,  which  is  enabled  by  optimizations  in most\ntargets.  The precision of the warnings depends on the optimization options used.\n"
                },
                {
                    "name": "-Winfinite-recursion",
                    "content": "Warn about infinitely recursive calls.  The warning  is  effective  at  all  optimization\nlevels  but  requires optimization in order to detect infinite recursion in calls between\ntwo or more functions.  -Winfinite-recursion is included in -Wall.\n\nCompare with -Wanalyzer-infinite-recursion which provides a similar  diagnostic,  but  is\nimplemented in a different way (as part of -fanalyzer).\n"
                },
                {
                    "name": "-Winit-self",
                    "content": "Warn  about  uninitialized  variables  that  are  initialized with themselves.  Note this\noption can only be used with the -Wuninitialized option.\n\nFor example, GCC warns about \"i\" being uninitialized in the following snippet  only  when\n-Winit-self has been specified:\n\nint f()\n{\nint i = i;\nreturn i;\n}\n\nThis warning is enabled by -Wall in C++.\n"
                },
                {
                    "name": "-Wno-implicit-int",
                    "content": "This  option  controls warnings when a declaration does not specify a type.  This warning\nis enabled by default in C99 and later dialects of C, and also by -Wall.\n"
                },
                {
                    "name": "-Wno-implicit-function-declaration",
                    "content": "This option controls warnings when a  function  is  used  before  being  declared.   This\nwarning  is  enabled  by  default in C99 and later dialects of C, and also by -Wall.  The\nwarning is made into an error by -pedantic-errors.\n"
                },
                {
                    "name": "-Wimplicit",
                    "content": "Same as -Wimplicit-int and -Wimplicit-function-declaration.  This warning is  enabled  by\n-Wall.\n"
                },
                {
                    "name": "-Wimplicit-fallthrough",
                    "content": "-Wimplicit-fallthrough     is     the     same     as     -Wimplicit-fallthrough=3    and\n-Wno-implicit-fallthrough is the same as -Wimplicit-fallthrough=0.\n"
                },
                {
                    "name": "-Wimplicit-fallthrough=_",
                    "content": "Warn when a switch case falls through.  For example:\n\nswitch (cond)\n{\ncase 1:\na = 1;\nbreak;\ncase 2:\na = 2;\ncase 3:\na = 3;\nbreak;\n}\n\nThis warning does not warn when the last statement of a case cannot  fall  through,  e.g.\nwhen  there  is  a  return  statement  or  a  call to function declared with the noreturn\nattribute.  -Wimplicit-fallthrough= also takes into account control flow statements, such\nas ifs, and only warns when appropriate.  E.g.\n\nswitch (cond)\n{\ncase 1:\nif (i > 3) {\nbar (5);\nbreak;\n} else if (i < 1) {\nbar (0);\n} else\nreturn;\ndefault:\n...\n}\n\nSince there are occasions where a switch case fall through is desirable, GCC provides  an\nattribute,  \"attribute  ((fallthrough))\",  that  is  to  be  used  along  with a null\nstatement to suppress this warning that would normally occur:\n\nswitch (cond)\n{\ncase 1:\nbar (0);\nattribute ((fallthrough));\ndefault:\n...\n}\n\nC++17 provides a standard  way  to  suppress  the  -Wimplicit-fallthrough  warning  using\n\"[[fallthrough]];\"  instead  of  the  GNU  attribute.   In  C++11  or C++14 users can use\n\"[[gnu::fallthrough]];\", which is a GNU extension.  Instead of these  attributes,  it  is\nalso possible to add a fallthrough comment to silence the warning.  The whole body of the\nC  or  C++  style  comment  should match the given regular expressions listed below.  The\noption argument n specifies what kind of comments are accepted:\n\n*<-Wimplicit-fallthrough=0 disables the warning altogether.>\n*<-Wimplicit-fallthrough=1 matches \".*\" regular>\nexpression, any comment is used as fallthrough comment.\n\n*<-Wimplicit-fallthrough=2 case insensitively matches>\n\".*falls?[ \\t-]*thr(ough|u).*\" regular expression.\n\n*<-Wimplicit-fallthrough=3 case sensitively matches one of the>\nfollowing regular expressions:\n\n*<\"-fallthrough\">\n*<\"@fallthrough@\">\n*<\"lint -fallthrough[ \\t]*\">\n*<\"[ \\t.!]*(ELSE,? |INTENTIONAL(LY)? )?FALL(S | |-)?THR(OUGH|U)[ \\t.!]*(-[^\\n\\r]*)?\">\n*<\"[ \\t.!]*(Else,? |Intentional(ly)? )?Fall((s | |-)[Tt]|t)hr(ough|u)[\n\\t.!]*(-[^\\n\\r]*)?\">\n*<\"[ \\t.!]*([Ee]lse,? |[Ii]ntentional(ly)? )?fall(s | |-)?thr(ough|u)[\n\\t.!]*(-[^\\n\\r]*)?\">\n*<-Wimplicit-fallthrough=4 case sensitively matches one of the>\nfollowing regular expressions:\n\n*<\"-fallthrough\">\n*<\"@fallthrough@\">\n*<\"lint -fallthrough[ \\t]*\">\n*<\"[ \\t]*FALLTHR(OUGH|U)[ \\t]*\">\n*<-Wimplicit-fallthrough=5 doesn't recognize any comments as>\nfallthrough comments, only attributes disable the warning.\n\nThe comment needs to be followed after optional whitespace and other comments  by  \"case\"\nor \"default\" keywords or by a user label that precedes some \"case\" or \"default\" label.\n\nswitch (cond)\n{\ncase 1:\nbar (0);\n/* FALLTHRU */\ndefault:\n...\n}\n\nThe -Wimplicit-fallthrough=3 warning is enabled by -Wextra.\n"
                },
                {
                    "name": "-Wno-if-not-aligned",
                    "content": "Control  if  warnings  triggered by the \"warnifnotaligned\" attribute should be issued.\nThese warnings are enabled by default.\n"
                },
                {
                    "name": "-Wignored-qualifiers",
                    "content": "Warn if the return type of a function has a type qualifier such as \"const\".   For  ISO  C\nsuch  a  type  qualifier  has no effect, since the value returned by a function is not an\nlvalue.  For C++, the warning is  only  emitted  for  scalar  types  or  \"void\".   ISO  C\nprohibits  qualified  \"void\"  return  types on function definitions, so such return types\nalways receive a warning even without this option.\n\nThis warning is also enabled by -Wextra.\n"
                },
                {
                    "name": "-Wno-ignored-attributes",
                    "content": "This option controls warnings when an attribute is ignored.  This is different  from  the\n-Wattributes  option in that it warns whenever the compiler decides to drop an attribute,\nnot that the attribute is either unknown, used in a wrong place, etc.   This  warning  is\nenabled by default.\n"
                },
                {
                    "name": "-Wmain",
                    "content": "Warn  if  the  type  of  \"main\" is suspicious.  \"main\" should be a function with external\nlinkage, returning int,  taking  either  zero  arguments,  two,  or  three  arguments  of\nappropriate  types.   This  warning is enabled by default in C++ and is enabled by either\n-Wall or -Wpedantic.\n"
                },
                {
                    "name": "-Wmisleading-indentation",
                    "content": "Warn  when  the  indentation  of  the  code  does  not  reflect  the   block   structure.\nSpecifically,  a  warning  is  issued for \"if\", \"else\", \"while\", and \"for\" clauses with a\nguarded statement that does not use braces, followed by an unguarded statement  with  the\nsame indentation.\n\nIn  the  following  example,  the  call  to  \"bar\" is misleadingly indented as if it were\nguarded by the \"if\" conditional.\n\nif (somecondition ())\nfoo ();\nbar ();  /* Gotcha: this is not guarded by the \"if\".  */\n\nIn the case of mixed tabs and spaces, the warning uses the -ftabstop= option to determine\nif the statements line up (defaulting to 8).\n\nThe warning is not issued for code involving multiline preprocessor  logic  such  as  the\nfollowing example.\n\nif (flagA)\nfoo (0);\n#if SOMECONDITIONTHATDOESNOTHOLD\nif (flagB)\n#endif\nfoo (1);\n\nThe  warning  is  not  issued  after  a \"#line\" directive, since this typically indicates\nautogenerated code, and no assumptions can be made about the layout of the file that  the\ndirective references.\n\nThis warning is enabled by -Wall in C and C++.\n"
                },
                {
                    "name": "-Wmissing-attributes",
                    "content": "Warn  when  a  declaration of a function is missing one or more attributes that a related\nfunction is declared with and whose absence  may  adversely  affect  the  correctness  or\nefficiency  of  generated  code.   For example, the warning is issued for declarations of\naliases that use attributes to specify less restrictive requirements than those of  their\ntargets.   This  typically represents a potential optimization opportunity.  By contrast,\nthe  -Wattribute-alias=2  option  controls  warnings  issued  when  the  alias  is   more\nrestrictive  than  the target, which could lead to incorrect code generation.  Attributes\nconsidered include \"allocalign\", \"allocsize\", \"cold\", \"const\", \"hot\", \"leaf\", \"malloc\",\n\"nonnull\", \"noreturn\", \"nothrow\", \"pure\", \"returnsnonnull\", and \"returnstwice\".\n\nIn C++, the warning is issued when an  explicit  specialization  of  a  primary  template\ndeclared   with   attribute   \"allocalign\",  \"allocsize\",  \"assumealigned\",  \"format\",\n\"formatarg\", \"malloc\", or \"nonnull\" is declared without  it.   Attributes  \"deprecated\",\n\"error\", and \"warning\" suppress the warning..\n\nYou  can use the \"copy\" attribute to apply the same set of attributes to a declaration as\nthat on another declaration without explicitly enumerating the attributes. This attribute\ncan be applied to declarations of functions, variables, or types.\n\n-Wmissing-attributes is enabled by -Wall.\n\nFor example, since the declaration of the primary function template below  makes  use  of\nboth  attribute  \"malloc\" and \"allocsize\" the declaration of the explicit specialization\nof the template is diagnosed because it is missing one of the attributes.\n\ntemplate <class T>\nT* attribute ((malloc, allocsize (1)))\nallocate (sizet);\n\ntemplate <>\nvoid* attribute ((malloc))   // missing allocsize\nallocate<void> (sizet);\n"
                },
                {
                    "name": "-Wmissing-braces",
                    "content": "Warn if an aggregate or union initializer is  not  fully  bracketed.   In  the  following\nexample,  the  initializer  for  \"a\"  is  not  fully bracketed, but that for \"b\" is fully\nbracketed.\n\nint a[2][2] = { 0, 1, 2, 3 };\nint b[2][2] = { { 0, 1 }, { 2, 3 } };\n\nThis warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wmissing-include-dirs",
                    "content": "Warn if a user-supplied include directory does not exist.  This  option  is  disabled  by\ndefault  for  C, C++, Objective-C and Objective-C++. For Fortran, it is partially enabled\nby default by warning for -I and -J, only.\n"
                },
                {
                    "name": "-Wno-missing-profile",
                    "content": "This  option  controls  warnings  if  feedback  profiles  are  missing  when  using   the\n-fprofile-use  option.   This  option diagnoses those cases where a new function or a new\nfile is added between compiling with -fprofile-generate and with  -fprofile-use,  without\nregenerating  the  profiles.   In  these  cases,  the  profile feedback data files do not\ncontain  any  profile  feedback  information  for  the  newly  added  function  or   file\nrespectively.   Also,  in the case when profile count data (.gcda) files are removed, GCC\ncannot use any profile feedback information.  In all these cases, warnings are issued  to\ninform  you  that  a  profile generation step is due.  Ignoring the warning can result in\npoorly optimized code.  -Wno-missing-profile can be used to disable the warning, but this\nis not recommended and should be done only when non-existent profile data is justified.\n"
                },
                {
                    "name": "-Wmismatched-dealloc",
                    "content": "Warn for calls to deallocation  functions  with  pointer  arguments  returned  from  from\nallocations  functions  for  which  the  former  isn't a suitable deallocator.  A pair of\nfunctions can be associated as matching allocators and deallocators by use  of  attribute\n\"malloc\".   Unless  disabled  by the -fno-builtin option the standard functions \"calloc\",\n\"malloc\", \"realloc\", and \"free\", as well as the corresponding forms of C++ \"operator new\"\nand \"operator delete\" are implicitly associated as matching allocators and  deallocators.\nIn  the  following  example  \"mydealloc\"  is  the  deallocator for pointers returned from\n\"myalloc\".\n\nvoid mydealloc (void*);\n\nattribute ((malloc (mydealloc, 1))) void*\nmyalloc (sizet);\n\nvoid f (void)\n{\nvoid *p = myalloc (32);\n// ...use p...\nfree (p);   // warning: not a matching deallocator for myalloc\nmydealloc (p);   // ok\n}\n\nIn C++, the related option -Wmismatched-new-delete diagnoses mismatches involving  either\n\"operator new\" or \"operator delete\".\n\nOption -Wmismatched-dealloc is included in -Wall.\n"
                },
                {
                    "name": "-Wmultistatement-macros",
                    "content": "Warn about unsafe multiple statement macros that appear to be guarded by a clause such as\n\"if\",  \"else\", \"for\", \"switch\", or \"while\", in which only the first statement is actually\nguarded after the macro is expanded.\n\nFor example:\n\n#define DOIT x++; y++\nif (c)\nDOIT;\n\nwill increment \"y\" unconditionally, not just when \"c\" holds.  The can usually be fixed by\nwrapping the macro in a do-while loop:\n\n#define DOIT do { x++; y++; } while (0)\nif (c)\nDOIT;\n\nThis warning is enabled by -Wall in C and C++.\n"
                },
                {
                    "name": "-Wparentheses",
                    "content": "Warn if parentheses are omitted in certain contexts, such as when there is an  assignment\nin  a  context  where  a  truth  value  is  expected,  or when operators are nested whose\nprecedence people often get confused about.\n\nAlso warn if a comparison like \"x<=y<=z\" appears; this is equivalent to \"(x<=y ? 1  :  0)\n<= z\", which is a different interpretation from that of ordinary mathematical notation.\n\nAlso  warn  for  dangerous uses of the GNU extension to \"?:\" with omitted middle operand.\nWhen the condition in the \"?\": operator is a boolean expression,  the  omitted  value  is\nalways  1.   Often  programmers  expect  it to be a value computed inside the conditional\nexpression instead.\n\nFor C++ this also warns for some cases of unnecessary parentheses in declarations,  which\ncan indicate an attempt at a function call instead of a declaration:\n\n{\n// Declares a local variable called mymutex.\nstd::uniquelock<std::mutex> (mymutex);\n// User meant std::uniquelock<std::mutex> lock (mymutex);\n}\n\nThis warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wno-self-move",
                    "content": "This  warning warns when a value is moved to itself with \"std::move\".  Such a \"std::move\"\ntypically has no effect.\n\nstruct T {\n...\n};\nvoid fn()\n{\nT t;\n...\nt = std::move (t);\n}\n\nThis warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wsequence-point",
                    "content": "Warn about code that may have undefined semantics because of violations of sequence point\nrules in the C and C++ standards.\n\nThe C and C++ standards define the order in which expressions  in  a  C/C++  program  are\nevaluated  in  terms  of  sequence points, which represent a partial ordering between the\nexecution of parts of the program: those executed before the sequence  point,  and  those\nexecuted  after  it.  These occur after the evaluation of a full expression (one which is\nnot part of a larger expression), after the evaluation of the first operand  of  a  \"&&\",\n\"||\",  \"?  :\"  or  \",\"  (comma)  operator,  before  a  function  is called (but after the\nevaluation of its arguments and the expression denoting  the  called  function),  and  in\ncertain  other places.  Other than as expressed by the sequence point rules, the order of\nevaluation of subexpressions of an expression is not specified.  All these rules describe\nonly a partial order rather than a total order, since, for example, if two functions  are\ncalled  within one expression with no sequence point between them, the order in which the\nfunctions are called is not specified.  However, the standards committee have ruled  that\nfunction calls do not overlap.\n\nIt  is  not specified when between sequence points modifications to the values of objects\ntake effect.  Programs whose behavior depends on this have undefined behavior; the C  and\nC++  standards specify that \"Between the previous and next sequence point an object shall\nhave its stored value  modified  at  most  once  by  the  evaluation  of  an  expression.\nFurthermore,  the  prior  value shall be read only to determine the value to be stored.\".\nIf a program breaks these  rules,  the  results  on  any  particular  implementation  are\nentirely unpredictable.\n\nExamples  of  code  with undefined behavior are \"a = a++;\", \"a[n] = b[n++]\" and \"a[i++] =\ni;\".  Some more complicated cases are not diagnosed by this option, and it  may  give  an\noccasional  false  positive  result, but in general it has been found fairly effective at\ndetecting this sort of problem in programs.\n\nThe C++17 standard will define the order of evaluation of  operands  in  more  cases:  in\nparticular  it requires that the right-hand side of an assignment be evaluated before the\nleft-hand side, so the above examples are no longer  undefined.   But  this  option  will\nstill  warn  about  them,  to  help  people avoid writing code that is undefined in C and\nearlier revisions of C++.\n\nThe standard is worded confusingly, therefore there  is  some  debate  over  the  precise\nmeaning  of  the  sequence  point  rules  in  subtle  cases.  Links to discussions of the\nproblem, including proposed formal definitions, may be found on the GCC readings page, at\n<https://gcc.gnu.org/readings.html>.\n\nThis warning is enabled by -Wall for C and C++.\n"
                },
                {
                    "name": "-Wno-return-local-addr",
                    "content": "Do not warn about returning a pointer (or in C++, a reference) to a  variable  that  goes\nout of scope after the function returns.\n"
                },
                {
                    "name": "-Wreturn-type",
                    "content": "Warn whenever a function is defined with a return type that defaults to \"int\".  Also warn\nabout  any \"return\" statement with no return value in a function whose return type is not\n\"void\" (falling off the end of the  function  body  is  considered  returning  without  a\nvalue).\n\nFor C only, warn about a \"return\" statement with an expression in a function whose return\ntype  is  \"void\",  unless  the  expression  type is also \"void\".  As a GNU extension, the\nlatter case is accepted without a warning unless -Wpedantic is used.  Attempting  to  use\nthe  return  value  of  a non-\"void\" function other than \"main\" that flows off the end by\nreaching the closing curly brace that terminates the function is undefined.\n\nUnlike in C, in C++, flowing off the end of  a  non-\"void\"  function  other  than  \"main\"\nresults in undefined behavior even when the value of the function is not used.\n\nThis warning is enabled by default in C++ and by -Wall otherwise.\n"
                },
                {
                    "name": "-Wno-shift-count-negative",
                    "content": "Controls warnings if a shift count is negative.  This warning is enabled by default.\n"
                },
                {
                    "name": "-Wno-shift-count-overflow",
                    "content": "Controls warnings if a shift count is greater than or equal to the bit width of the type.\nThis warning is enabled by default.\n"
                },
                {
                    "name": "-Wshift-negative-value",
                    "content": "Warn  if  left shifting a negative value.  This warning is enabled by -Wextra in C99 (and\nnewer) and C++11 to C++17 modes.\n"
                },
                {
                    "name": "-Wno-shift-overflow",
                    "content": ""
                },
                {
                    "name": "-Wshift-overflow=_",
                    "content": "These options control warnings about left shift overflows.\n\n-Wshift-overflow=1\nThis is the warning level of -Wshift-overflow and is enabled by default  in  C99  and\nC++11 modes (and newer).  This warning level does not warn about left-shifting 1 into\nthe  sign  bit.  (However, in C, such an overflow is still rejected in contexts where\nan integer constant expression is required.)  No warning is  emitted  in  C++20  mode\n(and newer), as signed left shifts always wrap.\n\n-Wshift-overflow=2\nThis  warning  level also warns about left-shifting 1 into the sign bit, unless C++14\nmode (or newer) is active.\n"
                },
                {
                    "name": "-Wswitch",
                    "content": "Warn whenever a \"switch\" statement has an index of enumerated type and lacks a \"case\" for\none or more of the named codes of that enumeration.  (The presence of a  \"default\"  label\nprevents  this  warning.)   \"case\"  labels  outside  the  enumeration  range also provoke\nwarnings when this option is used (even if there is a \"default\" label).  This warning  is\nenabled by -Wall.\n"
                },
                {
                    "name": "-Wswitch-default",
                    "content": "Warn whenever a \"switch\" statement does not have a \"default\" case.\n"
                },
                {
                    "name": "-Wswitch-enum",
                    "content": "Warn whenever a \"switch\" statement has an index of enumerated type and lacks a \"case\" for\none  or  more  of  the  named  codes  of  that  enumeration.   \"case\"  labels outside the\nenumeration range also provoke warnings when this option is used.   The  only  difference\nbetween  -Wswitch  and  this  option is that this option gives a warning about an omitted\nenumeration code even if there is a \"default\" label.\n"
                },
                {
                    "name": "-Wno-switch-bool",
                    "content": "Do not warn when a \"switch\" statement has an index of boolean type and  the  case  values\nare  outside  the  range  of  a boolean type.  It is possible to suppress this warning by\ncasting the controlling expression to a type other than \"bool\".  For example:\n\nswitch ((int) (a == 4))\n{\n...\n}\n\nThis warning is enabled by default for C and C++ programs.\n"
                },
                {
                    "name": "-Wno-switch-outside-range",
                    "content": "This option controls warnings when a \"switch\" case has a value that  is  outside  of  its\nrespective type range.  This warning is enabled by default for C and C++ programs.\n"
                },
                {
                    "name": "-Wno-switch-unreachable",
                    "content": "Do  not  warn  when  a  \"switch\"  statement  contains  statements between the controlling\nexpression and the first case label, which will never be executed.  For example:\n\nswitch (cond)\n{\ni = 15;\n...\ncase 5:\n...\n}\n\n-Wswitch-unreachable does not warn if the statement between  the  controlling  expression\nand the first case label is just a declaration:\n\nswitch (cond)\n{\nint i;\n...\ncase 5:\ni = 5;\n...\n}\n\nThis warning is enabled by default for C and C++ programs.\n"
                },
                {
                    "name": "-Wsync-nand",
                    "content": "Warn  when  \"syncfetchandnand\"  and  \"syncnandandfetch\"  built-in functions are\nused.  These functions changed semantics in GCC 4.4.\n"
                },
                {
                    "name": "-Wtrivial-auto-var-init",
                    "content": "Warn when \"-ftrivial-auto-var-init\" cannot initialize the automatic variable.   A  common\nsituation  is  an  automatic variable that is declared between the controlling expression\nand the first case label of a \"switch\" statement.\n"
                },
                {
                    "name": "-Wunused-but-set-parameter",
                    "content": "Warn whenever a function parameter is assigned to, but otherwise unused (aside  from  its\ndeclaration).\n\nTo suppress this warning use the \"unused\" attribute.\n\nThis warning is also enabled by -Wunused together with -Wextra.\n"
                },
                {
                    "name": "-Wunused-but-set-variable",
                    "content": "Warn  whenever  a  local  variable  is  assigned to, but otherwise unused (aside from its\ndeclaration).  This warning is enabled by -Wall.\n\nTo suppress this warning use the \"unused\" attribute.\n\nThis warning is also enabled by -Wunused, which is enabled by -Wall.\n"
                },
                {
                    "name": "-Wunused-function",
                    "content": "Warn whenever a static function is declared  but  not  defined  or  a  non-inline  static\nfunction is unused.  This warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wunused-label",
                    "content": "Warn whenever a label is declared but not used.  This warning is enabled by -Wall.\n\nTo suppress this warning use the \"unused\" attribute.\n"
                },
                {
                    "name": "-Wunused-local-typedefs",
                    "content": "Warn  when  a typedef locally defined in a function is not used.  This warning is enabled\nby -Wall.\n"
                },
                {
                    "name": "-Wunused-parameter",
                    "content": "Warn whenever a function parameter is unused aside from its declaration.\n\nTo suppress this warning use the \"unused\" attribute.\n"
                },
                {
                    "name": "-Wno-unused-result",
                    "content": "Do not warn if a caller of a function marked with attribute \"warnunusedresult\" does not\nuse its return value. The default is -Wunused-result.\n"
                },
                {
                    "name": "-Wunused-variable",
                    "content": "Warn whenever a local or static variable is  unused  aside  from  its  declaration.  This\noption  implies -Wunused-const-variable=1 for C, but not for C++. This warning is enabled\nby -Wall.\n\nTo suppress this warning use the \"unused\" attribute.\n"
                },
                {
                    "name": "-Wunused-const-variable",
                    "content": ""
                },
                {
                    "name": "-Wunused-const-variable=_",
                    "content": "Warn  whenever  a  constant  static  variable  is  unused  aside  from  its  declaration.\n-Wunused-const-variable=1  is  enabled  by -Wunused-variable for C, but not for C++. In C\nthis declares variable storage, but in C++ this is not an  error  since  const  variables\ntake the place of \"#define\"s.\n\nTo suppress this warning use the \"unused\" attribute.\n\n-Wunused-const-variable=1\nThis  is the warning level that is enabled by -Wunused-variable for C.  It warns only\nabout unused static const variables defined in the main  compilation  unit,  but  not\nabout static const variables declared in any header included.\n\n-Wunused-const-variable=2\nThis  warning  level  also  warns  for  unused  constant  static variables in headers\n(excluding system headers).  This is the warning level of -Wunused-const-variable and\nmust be explicitly requested since in C++ this isn't an error and in C  it  might  be\nharder to clean up all headers included.\n"
                },
                {
                    "name": "-Wunused-value",
                    "content": "Warn whenever a statement computes a result that is explicitly not used. To suppress this\nwarning  cast  the  unused expression to \"void\". This includes an expression-statement or\nthe left-hand side of a comma expression that contains no side effects. For  example,  an\nexpression such as \"x[i,j]\" causes a warning, while \"x[(void)i,j]\" does not.\n\nThis warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wunused",
                    "content": "All the above -Wunused options combined.\n\nIn  order  to  get  a warning about an unused function parameter, you must either specify\n-Wextra  -Wunused  (note  that   -Wall   implies   -Wunused),   or   separately   specify\n-Wunused-parameter.\n"
                },
                {
                    "name": "-Wuninitialized",
                    "content": "Warn  if  an  object  with automatic or allocated storage duration is used without having\nbeen initialized.  In C++, also warn if a  non-static  reference  or  non-static  \"const\"\nmember appears in a class without constructors.\n\nIn  addition,  passing a pointer (or in C++, a reference) to an uninitialized object to a\n\"const\"-qualified argument of a built-in function  known  to  read  the  object  is  also\ndiagnosed by this warning.  (-Wmaybe-uninitialized is issued for ordinary functions.)\n\nIf  you  want to warn about code that uses the uninitialized value of the variable in its\nown initializer, use the -Winit-self option.\n\nThese warnings occur for individual uninitialized elements of structure, union  or  array\nvariables  as well as for variables that are uninitialized as a whole.  They do not occur\nfor variables  or  elements  declared  \"volatile\".   Because  these  warnings  depend  on\noptimization,  the exact variables or elements for which there are warnings depend on the\nprecise optimization options and version of GCC used.\n\nNote that there may be no warning about a variable that is used only to compute  a  value\nthat itself is never used, because such computations may be deleted by data flow analysis\nbefore the warnings are printed.\n\nIn  C++, this warning also warns about using uninitialized objects in member-initializer-\nlists.  For example, GCC warns about \"b\" being uninitialized in the following snippet:\n\nstruct A {\nint a;\nint b;\nA() : a(b) { }\n};\n"
                },
                {
                    "name": "-Wno-invalid-memory-model",
                    "content": "This option controls warnings for invocations of atomic Builtins, sync Builtins,  and\nthe  C11  atomic  generic  functions  with  a  memory consistency argument that is either\ninvalid for  the  operation  or  outside  the  range  of  values  of  the  \"memoryorder\"\nenumeration.   For  example,  since the \"atomicstore\" and \"atomicstoren\" built-ins\nare only defined for the relaxed, release, and sequentially consistent memory orders  the\nfollowing code is diagnosed:\n\nvoid store (int *i)\n{\natomicstoren (i, 0, memoryorderconsume);\n}\n\n-Winvalid-memory-model is enabled by default.\n"
                },
                {
                    "name": "-Wmaybe-uninitialized",
                    "content": "For  an  object with automatic or allocated storage duration, if there exists a path from\nthe function entry to a use of the object that is initialized, but there exist some other\npaths for which the object is not initialized, the compiler emits a warning if it  cannot\nprove the uninitialized paths are not executed at run time.\n\nIn  addition,  passing a pointer (or in C++, a reference) to an uninitialized object to a\n\"const\"-qualified function argument is also diagnosed by this warning.   (-Wuninitialized\nis issued for built-in functions known to read the object.)  Annotating the function with\nattribute \"access (none)\" indicates that the argument isn't used to access the object and\navoids the warning.\n\nThese  warnings  are  only possible in optimizing compilation, because otherwise GCC does\nnot keep track of the state of variables.\n\nThese warnings are made optional because GCC may not be able to determine when  the  code\nis  correct  in spite of appearing to have an error.  Here is one example of how this can\nhappen:\n\n{\nint x;\nswitch (y)\n{\ncase 1: x = 1;\nbreak;\ncase 2: x = 4;\nbreak;\ncase 3: x = 5;\n}\nfoo (x);\n}\n\nIf the value of \"y\" is always 1, 2 or 3, then \"x\" is always initialized, but GCC  doesn't\nknow  this. To suppress the warning, you need to provide a default case with assert(0) or\nsimilar code.\n\nThis option also warns when a non-volatile automatic variable might be changed by a  call\nto  \"longjmp\".   The  compiler  sees  only  the  calls to \"setjmp\".  It cannot know where\n\"longjmp\" will be called; in fact, a signal handler could call it at  any  point  in  the\ncode.   As  a result, you may get a warning even when there is in fact no problem because\n\"longjmp\" cannot in fact be called at the place that would cause a problem.\n\nSome spurious warnings can be avoided if you declare all the functions you use that never\nreturn as \"noreturn\".\n\nThis warning is enabled by -Wall or -Wextra.\n"
                },
                {
                    "name": "-Wunknown-pragmas",
                    "content": "Warn when a \"#pragma\" directive is encountered that is not understood by  GCC.   If  this\ncommand-line  option  is  used,  warnings  are  even issued for unknown pragmas in system\nheader files.  This is not the case if  the  warnings  are  only  enabled  by  the  -Wall\ncommand-line option.\n"
                },
                {
                    "name": "-Wno-pragmas",
                    "content": "Do  not  warn  about misuses of pragmas, such as incorrect parameters, invalid syntax, or\nconflicts between pragmas.  See also -Wunknown-pragmas.\n"
                },
                {
                    "name": "-Wno-prio-ctor-dtor",
                    "content": "Do not warn if a priority from 0 to 100 is used for constructor or destructor.   The  use\nof  constructor  and  destructor  attributes  allow  you  to  assign  a  priority  to the\nconstructor/destructor to control its order of execution before \"main\" is called or after\nit returns.  The priority values must be  greater  than  100  as  the  compiler  reserves\npriority values between 0--100 for the implementation.\n"
                },
                {
                    "name": "-Wstrict-aliasing",
                    "content": "This  option  is  only active when -fstrict-aliasing is active.  It warns about code that\nmight break the strict aliasing rules that the compiler is using for  optimization.   The\nwarning does not catch all cases, but does attempt to catch the more common pitfalls.  It\nis included in -Wall.  It is equivalent to -Wstrict-aliasing=3\n"
                },
                {
                    "name": "-Wstrict-aliasing=n",
                    "content": "This  option  is  only active when -fstrict-aliasing is active.  It warns about code that\nmight break the strict aliasing rules  that  the  compiler  is  using  for  optimization.\nHigher  levels correspond to higher accuracy (fewer false positives).  Higher levels also\ncorrespond to more effort, similar to the way -O works.  -Wstrict-aliasing is  equivalent\nto -Wstrict-aliasing=3.\n\nLevel  1:  Most aggressive, quick, least accurate.  Possibly useful when higher levels do\nnot warn but -fstrict-aliasing still breaks the code, as it has very few false negatives.\nHowever, it has many false positives.  Warns for all pointer conversions between possibly\nincompatible types, even if never dereferenced.  Runs in the front end only.\n\nLevel 2: Aggressive, quick, not too precise.  May still have many false positives (not as\nmany as level 1 though), and few false  negatives  (but  possibly  more  than  level  1).\nUnlike  level  1,  it only warns when an address is taken.  Warns about incomplete types.\nRuns in the front end only.\n\nLevel 3 (default for -Wstrict-aliasing): Should have very few  false  positives  and  few\nfalse negatives.  Slightly slower than levels 1 or 2 when optimization is enabled.  Takes\ncare  of  the  common pun+dereference pattern in the front end: \"*(int*)&somefloat\".  If\noptimization is enabled, it also runs in the back  end,  where  it  deals  with  multiple\nstatement  cases  using  flow-sensitive  points-to  information.   Only  warns  when  the\nconverted pointer is dereferenced.  Does not warn about incomplete types.\n"
                },
                {
                    "name": "-Wstrict-overflow",
                    "content": ""
                },
                {
                    "name": "-Wstrict-overflow=_",
                    "content": "This option is only active when signed overflow is undefined.  It warns about cases where\nthe compiler optimizes based on the assumption that signed overflow does not occur.  Note\nthat it does not warn about all cases where the code might overflow: it only warns  about\ncases  where the compiler implements some optimization.  Thus this warning depends on the\noptimization level.\n\nAn optimization that assumes that signed overflow does not occur is perfectly safe if the\nvalues of the variables involved are such that  overflow  never  does,  in  fact,  occur.\nTherefore this warning can easily give a false positive: a warning about code that is not\nactually  a  problem.   To  help  focus  on  important issues, several warning levels are\ndefined.  No warnings are issued for the use of undefined signed overflow when estimating\nhow many iterations a loop requires, in particular when determining whether a  loop  will\nbe executed at all.\n\n-Wstrict-overflow=1\nWarn  about  cases  that  are  both  questionable and easy to avoid.  For example the\ncompiler simplifies \"x + 1 > x\" to 1.  This level of -Wstrict-overflow is enabled  by\n-Wall; higher levels are not, and must be explicitly requested.\n\n-Wstrict-overflow=2\nAlso  warn  about  other  cases  where a comparison is simplified to a constant.  For\nexample: \"abs (x) >= 0\".  This can only be simplified when signed integer overflow is\nundefined, because \"abs (INTMIN)\" overflows to \"INTMIN\", which is less  than  zero.\n-Wstrict-overflow (with no level) is the same as -Wstrict-overflow=2.\n\n-Wstrict-overflow=3\nAlso  warn about other cases where a comparison is simplified.  For example: \"x + 1 >\n1\" is simplified to \"x > 0\".\n\n-Wstrict-overflow=4\nAlso warn about other simplifications not covered by the above cases.   For  example:\n\"(x * 10) / 5\" is simplified to \"x * 2\".\n\n-Wstrict-overflow=5\nAlso warn about cases where the compiler reduces the magnitude of a constant involved\nin  a  comparison.   For example: \"x + 2 > y\" is simplified to \"x + 1 >= y\".  This is\nreported only at the highest warning level because  this  simplification  applies  to\nmany comparisons, so this warning level gives a very large number of false positives.\n"
                },
                {
                    "name": "-Wstring-compare",
                    "content": "Warn  for calls to \"strcmp\" and \"strncmp\" whose result is determined to be either zero or\nnon-zero in tests for such equality owing to the length of  one  argument  being  greater\nthan  the  size of the array the other argument is stored in (or the bound in the case of\n\"strncmp\").  Such calls could be mistakes.  For example, the call to  \"strcmp\"  below  is\ndiagnosed  because its result is necessarily non-zero irrespective of the contents of the\narray \"a\".\n\nextern char a[4];\nvoid f (char *d)\n{\nstrcpy (d, \"string\");\n...\nif (0 == strcmp (a, d))   // cannot be true\nputs (\"a and d are the same\");\n}\n\n-Wstring-compare is enabled by -Wextra.\n"
                },
                {
                    "name": "-Wno-stringop-overflow",
                    "content": ""
                },
                {
                    "name": "-Wstringop-overflow",
                    "content": ""
                },
                {
                    "name": "-Wstringop-overflow=_",
                    "content": "Warn for calls to string manipulation functions such as \"memcpy\" and  \"strcpy\"  that  are\ndetermined to overflow the destination buffer.  The optional argument is one greater than\nthe  type  of  Object  Size Checking to perform to determine the size of the destination.\nThe argument is meaningful only for functions that operate on character  arrays  but  not\nfor  raw memory functions like \"memcpy\" which always make use of Object Size type-0.  The\noption also warns for calls that specify a size in excess of the largest possible  object\nor  at most \"SIZEMAX / 2\" bytes.  The option produces the best results with optimization\nenabled  but  can  detect  a  small  subset  of  simple  buffer  overflows  even  without\noptimization  in  calls  to  the  GCC  built-in  functions  like  \"builtinmemcpy\" that\ncorrespond to the standard functions.  In any case, the option warns about just a  subset\nof  buffer  overflows  detected  by  the  corresponding overflow checking built-ins.  For\nexample, the option issues a warning for the \"strcpy\" call below  because  it  copies  at\nleast  5  characters (the string \"blue\" including the terminating NUL) into the buffer of\nsize 4.\n\nenum Color { blue, purple, yellow };\nconst char* f (enum Color clr)\n{\nstatic char buf [4];\nconst char *str;\nswitch (clr)\n{\ncase blue: str = \"blue\"; break;\ncase purple: str = \"purple\"; break;\ncase yellow: str = \"yellow\"; break;\n}\n\nreturn strcpy (buf, str);   // warning here\n}\n\nOption -Wstringop-overflow=2 is enabled by default.\n\n-Wstringop-overflow\n-Wstringop-overflow=1\nThe -Wstringop-overflow=1 option uses type-zero Object Size Checking to determine the\nsizes of destination objects.  At this setting the option does not  warn  for  writes\npast  the end of subobjects of larger objects accessed by pointers unless the size of\nthe largest surrounding object is known.  When the destination may be one of  several\nobjects  it  is  assumed  to  be  the  largest  one  of them.  On Linux systems, when\noptimization is enabled at this setting the option warns for the same  code  as  when\nthe \"FORTIFYSOURCE\" macro is defined to a non-zero value.\n\n-Wstringop-overflow=2\nThe  -Wstringop-overflow=2 option uses type-one Object Size Checking to determine the\nsizes of destination objects.  At this setting the option warns about overflows  when\nwriting  to  members  of  the  largest  complete  objects  whose exact size is known.\nHowever, it does not warn for excessive writes to the same members of unknown objects\nreferenced by pointers since they may point to arrays containing unknown  numbers  of\nelements.  This is the default setting of the option.\n\n-Wstringop-overflow=3\nThe  -Wstringop-overflow=3 option uses type-two Object Size Checking to determine the\nsizes of destination objects.  At this setting the option warns about overflowing the\nsmallest object or data member.  This is the most restrictive setting of  the  option\nthat may result in warnings for safe code.\n\n-Wstringop-overflow=4\nThe  -Wstringop-overflow=4  option  uses type-three Object Size Checking to determine\nthe sizes of destination objects.  At this setting the option warns about overflowing\nany data members, and when the destination is one of several objects it uses the size\nof the largest  of  them  to  decide  whether  to  issue  a  warning.   Similarly  to\n-Wstringop-overflow=3  this  setting  of the option may result in warnings for benign\ncode.\n"
                },
                {
                    "name": "-Wno-stringop-overread",
                    "content": "Warn for calls to string manipulation functions such as \"memchr\", or  \"strcpy\"  that  are\ndetermined to read past the end of the source sequence.\n\nOption -Wstringop-overread is enabled by default.\n"
                },
                {
                    "name": "-Wno-stringop-truncation",
                    "content": "Do  not  warn  for  calls  to  bounded  string  manipulation functions such as \"strncat\",\n\"strncpy\", and \"stpncpy\" that  may  either  truncate  the  copied  string  or  leave  the\ndestination unchanged.\n\nIn  the  following example, the call to \"strncat\" specifies a bound that is less than the\nlength of the source string.  As a result, the copy of the source will be  truncated  and\nso  the call is diagnosed.  To avoid the warning use \"bufsize - strlen (buf) - 1)\" as the\nbound.\n\nvoid append (char *buf, sizet bufsize)\n{\nstrncat (buf, \".txt\", 3);\n}\n\nAs another example, the following call to \"strncpy\" results in copying to  \"d\"  just  the\ncharacters preceding the terminating NUL, without appending the NUL to the end.  Assuming\nthe  result  of \"strncpy\" is necessarily a NUL-terminated string is a common mistake, and\nso the call is diagnosed.  To avoid the warning when the result is  not  expected  to  be\nNUL-terminated, call \"memcpy\" instead.\n\nvoid copy (char *d, const char *s)\n{\nstrncpy (d, s, strlen (s));\n}\n\nIn  the  following  example,  the call to \"strncpy\" specifies the size of the destination\nbuffer as the bound.  If the length of the source string is equal to or greater than this\nsize the result of the copy will not be NUL-terminated.   Therefore,  the  call  is  also\ndiagnosed.   To avoid the warning, specify \"sizeof buf - 1\" as the bound and set the last\nelement of the buffer to \"NUL\".\n\nvoid copy (const char *s)\n{\nchar buf[80];\nstrncpy (buf, s, sizeof buf);\n...\n}\n\nIn situations where a character array is intended to store a sequence of  bytes  with  no\nterminating \"NUL\" such an array may be annotated with attribute \"nonstring\" to avoid this\nwarning.   Such  arrays,  however,  are  not  suitable arguments to functions that expect\n\"NUL\"-terminated strings.  To help detect accidental misuses of such  arrays  GCC  issues\nwarnings unless it can prove that the use is safe.\n"
                },
                {
                    "name": "-Wstrict-flex-arrays",
                    "content": "Warn  about  inproper  usages  of  flexible  array  members according to the level of the\n\"strictflexarray (level)\" attribute attached to the trailing array field of a structure\nif   it's   available,   otherwise   according   to   the    level    of    the    option\n-fstrict-flex-arrays=level.\n\nThis option is effective only when level is bigger than 0.  Otherwise, it will be ignored\nwith a warning.\n\nwhen  level=1, warnings will be issued for a trailing array reference of a structure that\nhave 2 or more elements if the trailing array is referenced as a flexible array member.\n\nwhen level=2, in addition to level=1, additional warnings will be issued for  a  trailing\none-element array reference of a structure if the array is referenced as a flexible array\nmember.\n\nwhen  level=3,  in addition to level=2, additional warnings will be issued for a trailing\nzero-length array reference of a structure if the array is referenced as a flexible array\nmember.\n"
                },
                {
                    "name": "-Wsuggest-attribute=",
                    "content": "Warn for cases where adding an attribute may  be  beneficial.  The  attributes  currently\nsupported are listed below.\n\n-Wsuggest-attribute=pure\n-Wsuggest-attribute=const\n-Wsuggest-attribute=noreturn\n-Wmissing-noreturn\n-Wsuggest-attribute=malloc\nWarn  about  functions  that  might  be  candidates for attributes \"pure\", \"const\" or\n\"noreturn\" or \"malloc\". The compiler  only  warns  for  functions  visible  in  other\ncompilation  units or (in the case of \"pure\" and \"const\") if it cannot prove that the\nfunction returns normally. A function returns  normally  if  it  doesn't  contain  an\ninfinite  loop  or  return abnormally by throwing, calling \"abort\" or trapping.  This\nanalysis requires option -fipa-pure-const, which is enabled  by  default  at  -O  and\nhigher.  Higher optimization levels improve the accuracy of the analysis.\n\n-Wsuggest-attribute=format\n-Wmissing-format-attribute\nWarn  about function pointers that might be candidates for \"format\" attributes.  Note\nthese are only possible candidates, not absolute ones.   GCC  guesses  that  function\npointers  with  \"format\"  attributes  that  are  used  in assignment, initialization,\nparameter passing or return statements should have a corresponding \"format\" attribute\nin the resulting type.  I.e. the left-hand side of the assignment or  initialization,\nthe  type  of  the  parameter variable, or the return type of the containing function\nrespectively should also have a \"format\" attribute to avoid the warning.\n\nGCC also warns about function definitions  that  might  be  candidates  for  \"format\"\nattributes.   Again,  these  are only possible candidates.  GCC guesses that \"format\"\nattributes might be appropriate for any function that calls a function like \"vprintf\"\nor \"vscanf\", but this might not always be the case,  and  some  functions  for  which\n\"format\" attributes are appropriate may not be detected.\n\n-Wsuggest-attribute=cold\nWarn about functions that might be candidates for \"cold\" attribute.  This is based on\nstatic  detection  and  generally  only warns about functions which always leads to a\ncall to another \"cold\" function such as  wrappers  of  C++  \"throw\"  or  fatal  error\nreporting functions leading to \"abort\".\n"
                },
                {
                    "name": "-Walloc-zero",
                    "content": "Warn  about  calls  to  allocation  functions  decorated with attribute \"allocsize\" that\nspecify  zero  bytes,  including  those  to  the  built-in   forms   of   the   functions\n\"alignedalloc\",  \"alloca\",  \"calloc\",  \"malloc\", and \"realloc\".  Because the behavior of\nthese functions when called with a zero size differs among implementations  (and  in  the\ncase  of  \"realloc\"  has  been deprecated) relying on it may result in subtle portability\nbugs and should be avoided.\n"
                },
                {
                    "name": "-Walloc-size-larger-than=_",
                    "content": "Warn about calls to functions decorated  with  attribute  \"allocsize\"  that  attempt  to\nallocate  objects  larger  than the specified number of bytes, or where the result of the\nsize computation in an integer type with infinite precision would  exceed  the  value  of\nPTRDIFFMAX  on  the target.  -Walloc-size-larger-than=PTRDIFFMAX is enabled by default.\nWarnings controlled by the option can be  disabled  either  by  specifying  byte-size  of\nSIZEMAX or more or by -Wno-alloc-size-larger-than.\n"
                },
                {
                    "name": "-Wno-alloc-size-larger-than",
                    "content": "Disable    -Walloc-size-larger-than=    warnings.     The   option   is   equivalent   to\n-Walloc-size-larger-than=SIZEMAX or larger.\n"
                },
                {
                    "name": "-Walloca",
                    "content": "This option warns on all uses of \"alloca\" in the source.\n"
                },
                {
                    "name": "-Walloca-larger-than=_",
                    "content": "This option warns on calls to \"alloca\" with an integer argument  whose  value  is  either\nzero,  or that is not bounded by a controlling predicate that limits its value to at most\nbyte-size.  It also warns for calls  to  \"alloca\"  where  the  bound  value  is  unknown.\nArguments  of  non-integer  types  are  considered  unbounded  even  if they appear to be\nconstrained to the expected range.\n\nFor example, a bounded case of \"alloca\" could be:\n\nvoid func (sizet n)\n{\nvoid *p;\nif (n <= 1000)\np = alloca (n);\nelse\np = malloc (n);\nf (p);\n}\n\nIn the above example, passing  \"-Walloca-larger-than=1000\"  would  not  issue  a  warning\nbecause  the  call  to  \"alloca\"  is  known  to  be  at  most  1000  bytes.   However, if\n\"-Walloca-larger-than=500\" were passed, the compiler would emit a warning.\n\nUnbounded uses, on the other hand, are uses of \"alloca\"  with  no  controlling  predicate\nconstraining its integer argument.  For example:\n\nvoid func ()\n{\nvoid *p = alloca (n);\nf (p);\n}\n\nIf  \"-Walloca-larger-than=500\"  were  passed, the above would trigger a warning, but this\ntime because of the lack of bounds checking.\n\nNote, that even seemingly correct code involving signed integers could cause a warning:\n\nvoid func (signed int n)\n{\nif (n < 500)\n{\np = alloca (n);\nf (p);\n}\n}\n\nIn the above example, n could be negative, causing a larger than expected argument to  be\nimplicitly cast into the \"alloca\" call.\n\nThis option also warns when \"alloca\" is used in a loop.\n\n-Walloca-larger-than=PTRDIFFMAX  is  enabled  by  default  but is usually only effective\nwhen -ftree-vrp is active (default for -O2 and above).\n\nSee also -Wvla-larger-than=byte-size.\n"
                },
                {
                    "name": "-Wno-alloca-larger-than",
                    "content": "Disable    -Walloca-larger-than=    warnings.     The    option    is    equivalent    to\n-Walloca-larger-than=SIZEMAX or larger.\n"
                },
                {
                    "name": "-Warith-conversion",
                    "content": "Do warn about implicit conversions from arithmetic operations even when conversion of the\noperands  to  the  same  type  cannot  change  their  values.  This affects warnings from\n-Wconversion, -Wfloat-conversion, and -Wsign-conversion.\n\nvoid f (char c, int i)\n{\nc = c + i; // warns with B<-Wconversion>\nc = c + 1; // only warns with B<-Warith-conversion>\n}\n"
                },
                {
                    "name": "-Warray-bounds",
                    "content": ""
                },
                {
                    "name": "-Warray-bounds=_",
                    "content": "Warn about out of bounds subscripts or offsets into arrays.  This warning is  enabled  by\n-Wall.   It  is  more effective when -ftree-vrp is active (the default for -O2 and above)\nbut a subset of instances are issued even without optimization.\n\nBy default, the trailing array of a structure will be treated as a flexible array  member\nby -Warray-bounds or -Warray-bounds=n if it is declared as either a flexible array member\nper C99 standard onwards ([]), a GCC zero-length array extension ([0]), or an one-element\narray  ([1]). As a result, out of bounds subscripts or offsets into zero-length arrays or\none-element arrays are not warned by default.\n\nYou can add the option -fstrict-flex-arrays or -fstrict-flex-arrays=level to control  how\nthis option treat trailing array of a structure as a flexible array member:\n\nwhen level<=1, no change to the default behavior.\n\nwhen  level=2, additional warnings will be issued for out of bounds subscripts or offsets\ninto one-element arrays;\n\nwhen level=3, in addition to level=2, additional warnings  will  be  issued  for  out  of\nbounds subscripts or offsets into zero-length arrays.\n\n-Warray-bounds=1\nThis  is  the default warning level of -Warray-bounds and is enabled by -Wall; higher\nlevels are not, and must be explicitly requested.\n\n-Warray-bounds=2\nThis warning level also warns about the intermediate results  of  pointer  arithmetic\nthat  may  yield out of bounds values. This warning level may give a larger number of\nfalse positives and is deactivated by default.\n"
                },
                {
                    "name": "-Warray-compare",
                    "content": "Warn about equality and relational comparisons between two operands of array type.   This\ncomparison was deprecated in C++20.  For example:\n\nint arr1[5];\nint arr2[5];\nbool same = arr1 == arr2;\n\n-Warray-compare is enabled by -Wall.\n"
                },
                {
                    "name": "-Warray-parameter",
                    "content": ""
                },
                {
                    "name": "-Warray-parameter=_",
                    "content": "Warn  about  redeclarations of functions involving arguments of array or pointer types of\ninconsistent kinds or forms, and enable the detection of out-of-bounds accesses  to  such\nparameters by warnings such as -Warray-bounds.\n\nIf the first function declaration uses the array form the bound specified in the array is\nassumed  to  be  the  minimum  number of elements expected to be provided in calls to the\nfunction and the maximum number of elements accessed by it.  Failing to provide arguments\nof sufficient size or accessing more than the maximum number of elements may be diagnosed\nby warnings such as -Warray-bounds.  At level 1  the  warning  diagnoses  inconsistencies\ninvolving array parameters declared using the \"T[static N]\" form.\n\nFor  example, the warning triggers for the following redeclarations because the first one\nallows an array of any size to be passed to \"f\" while the second  one  with  the  keyword\n\"static\" specifies that the array argument must have at least four elements.\n\nvoid f (int[static 4]);\nvoid f (int[]);           // warning (inconsistent array form)\n\nvoid g (void)\n{\nint *p = (int *)malloc (4);\nf (p);                  // warning (array too small)\n...\n}\n\nAt level 2 the warning also triggers for redeclarations involving any other inconsistency\nin  array  or  pointer  argument  forms  denoting  array  sizes.   Pointers and arrays of\nunspecified bound are considered equivalent and do not trigger a warning.\n\nvoid g (int*);\nvoid g (int[]);     // no warning\nvoid g (int[8]);    // warning (inconsistent array bound)\n\n-Warray-parameter=2 is included in -Wall.  The -Wvla-parameter option  triggers  warnings\nfor similar inconsistencies involving Variable Length Array arguments.\n"
                },
                {
                    "name": "-Wattribute-alias=_",
                    "content": ""
                },
                {
                    "name": "-Wno-attribute-alias",
                    "content": "Warn  about  declarations  using  the  \"alias\"  and  similar  attributes  whose target is\nincompatible with the type of the alias.\n\n-Wattribute-alias=1\nThe default warning level of the -Wattribute-alias option diagnoses incompatibilities\nbetween  the  type  of  the  alias  declaration  and  that  of  its   target.    Such\nincompatibilities are typically indicative of bugs.\n\n-Wattribute-alias=2\nAt  this  level  -Wattribute-alias  also  diagnoses cases where the attributes of the\nalias declaration are more restrictive than the attributes  applied  to  its  target.\nThese mismatches can potentially result in incorrect code generation.  In other cases\nthey  may  be  benign and could be resolved simply by adding the missing attribute to\nthe target.  For comparison, see  the  -Wmissing-attributes  option,  which  controls\ndiagnostics  when  the  alias declaration is less restrictive than the target, rather\nthan more restrictive.\n\nAttributes considered include \"allocalign\", \"allocsize\",  \"cold\",  \"const\",  \"hot\",\n\"leaf\",  \"malloc\",  \"nonnull\",  \"noreturn\", \"nothrow\", \"pure\", \"returnsnonnull\", and\n\"returnstwice\".\n\n-Wattribute-alias is equivalent to -Wattribute-alias=1.  This is the  default.   You  can\ndisable these warnings with either -Wno-attribute-alias or -Wattribute-alias=0.\n"
                },
                {
                    "name": "-Wbidi-chars=",
                    "content": "Warn about possibly misleading UTF-8 bidirectional control characters in comments, string\nliterals, character constants, and identifiers.  Such characters can change left-to-right\nwriting  direction into right-to-left (and vice versa), which can cause confusion between\nthe logical order and visual order.  This may be dangerous; for  instance,  it  may  seem\nthat a piece of code is not commented out, whereas it in fact is.\n\nThere   are   three   levels   of   warning   supported   by   GCC.    The   default   is\n-Wbidi-chars=unpaired,  which  warns   about   improperly   terminated   bidi   contexts.\n-Wbidi-chars=none  turns  the  warning  off.   -Wbidi-chars=any  warns  about  any use of\nbidirectional control characters.\n\nBy default, this warning does not warn about UCNs.  It is, however, possible to  turn  on\nsuch   checking   by  using  -Wbidi-chars=unpaired,ucn  or  -Wbidi-chars=any,ucn.   Using\n-Wbidi-chars=ucn is valid, and is equivalent to -Wbidi-chars=unpaired,ucn, if no previous\n-Wbidi-chars=any was specified.\n"
                },
                {
                    "name": "-Wbool-compare",
                    "content": "Warn  about  boolean  expression  compared  with  an   integer   value   different   from\n\"true\"/\"false\".  For instance, the following comparison is always false:\n\nint n = 5;\n...\nif ((n > 1) == 2) { ... }\n\nThis warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wbool-operation",
                    "content": "Warn about suspicious operations on expressions of a boolean type.  For instance, bitwise\nnegation  of  a  boolean  is  very likely a bug in the program.  For C, this warning also\nwarns about incrementing or decrementing a boolean, which rarely makes sense.   (In  C++,\ndecrementing  a  boolean  is always invalid.  Incrementing a boolean is invalid in C++17,\nand deprecated otherwise.)\n\nThis warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wduplicated-branches",
                    "content": "Warn when an if-else has identical branches.  This warning detects cases like\n\nif (p != NULL)\nreturn 0;\nelse\nreturn 0;\n\nIt doesn't warn when both branches contain just a null statement.  This warning also warn\nfor conditional operators:\n\nint i = x ? *p : *p;\n"
                },
                {
                    "name": "-Wduplicated-cond",
                    "content": "Warn about duplicated conditions in an if-else-if chain.   For  instance,  warn  for  the\nfollowing code:\n\nif (p->q != NULL) { ... }\nelse if (p->q != NULL) { ... }\n"
                },
                {
                    "name": "-Wframe-address",
                    "content": "Warn  when  the  builtinframeaddress  or  builtinreturnaddress  is called with an\nargument greater than 0.  Such  calls  may  return  indeterminate  values  or  crash  the\nprogram.  The warning is included in -Wall.\n"
                },
                {
                    "name": "-Wno-discarded-qualifiers",
                    "content": "Do  not warn if type qualifiers on pointers are being discarded.  Typically, the compiler\nwarns if a \"const char *\" variable is  passed  to  a  function  that  takes  a  \"char  *\"\nparameter.  This option can be used to suppress such a warning.\n"
                },
                {
                    "name": "-Wno-discarded-array-qualifiers",
                    "content": "Do  not  warn if type qualifiers on arrays which are pointer targets are being discarded.\nTypically, the compiler warns if a \"const int (*)[]\" variable is  passed  to  a  function\nthat takes a \"int (*)[]\" parameter.  This option can be used to suppress such a warning.\n"
                },
                {
                    "name": "-Wno-incompatible-pointer-types",
                    "content": "Do  not  warn  when  there is a conversion between pointers that have incompatible types.\nThis warning is for cases not covered  by  -Wno-pointer-sign,  which  warns  for  pointer\nargument passing or assignment with different signedness.\n"
                },
                {
                    "name": "-Wno-int-conversion",
                    "content": "Do  not  warn  about  incompatible integer to pointer and pointer to integer conversions.\nThis warning is  about  implicit  conversions;  for  explicit  conversions  the  warnings\n-Wno-int-to-pointer-cast and -Wno-pointer-to-int-cast may be used.\n"
                },
                {
                    "name": "-Wzero-length-bounds",
                    "content": "Warn  about  accesses  to  elements of zero-length array members that might overlap other\nmembers of the same object.  Declaring interior zero-length arrays is discouraged because\naccesses to them are undefined.\n\nFor example, the first two stores in function  \"bad\"  are  diagnosed  because  the  array\nelements  overlap  the  subsequent  members \"b\" and \"c\".  The third store is diagnosed by\n-Warray-bounds because it is beyond the bounds of the enclosing object.\n\nstruct X { int a[0]; int b, c; };\nstruct X x;\n\nvoid bad (void)\n{\nx.a[0] = 0;   // -Wzero-length-bounds\nx.a[1] = 1;   // -Wzero-length-bounds\nx.a[2] = 2;   // -Warray-bounds\n}\n\nOption -Wzero-length-bounds is enabled by -Warray-bounds.\n"
                },
                {
                    "name": "-Wno-div-by-zero",
                    "content": "Do not warn about compile-time integer division by zero.  Floating-point division by zero\nis not warned about, as it can be a legitimate way of obtaining infinities and NaNs.\n"
                },
                {
                    "name": "-Wsystem-headers",
                    "content": "Print warning messages for constructs found in system header files.  Warnings from system\nheaders are normally suppressed, on the assumption that they usually do not indicate real\nproblems and would only make the compiler output harder to read.  Using this command-line\noption tells GCC to emit warnings from system headers as if they occurred in  user  code.\nHowever,  note  that  using  -Wall  in  conjunction  with this option does not warn about\nunknown pragmas in system headers---for that, -Wunknown-pragmas must also be used.\n"
                },
                {
                    "name": "-Wtautological-compare",
                    "content": "Warn if a self-comparison always evaluates  to  true  or  false.   This  warning  detects\nvarious mistakes such as:\n\nint i = 1;\n...\nif (i > i) { ... }\n\nThis  warning also warns about bitwise comparisons that always evaluate to true or false,\nfor instance:\n\nif ((a & 16) == 10) { ... }\n\nwill always be false.\n\nThis warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wtrampolines",
                    "content": "Warn about trampolines generated for pointers to nested functions.   A  trampoline  is  a\nsmall  piece of data or code that is created at run time on the stack when the address of\na nested function is taken, and is used to call the nested function indirectly.  For some\ntargets, it is made up of data only and thus requires no  special  treatment.   But,  for\nmost  targets, it is made up of code and thus requires the stack to be made executable in\norder for the program to work properly.\n"
                },
                {
                    "name": "-Wfloat-equal",
                    "content": "Warn if floating-point values are used in equality comparisons.\n\nThe idea behind this is that sometimes it is convenient (for the programmer) to  consider\nfloating-point  values  as approximations to infinitely precise real numbers.  If you are\ndoing this, then you need to compute (by analyzing the code, or in some  other  way)  the\nmaximum  or  likely  maximum error that the computation introduces, and allow for it when\nperforming comparisons (and when producing output, but that's a different  problem).   In\nparticular,  instead  of  testing  for  equality, you should check to see whether the two\nvalues have ranges that overlap; and this is  done  with  the  relational  operators,  so\nequality comparisons are probably mistaken.\n"
                },
                {
                    "name": "-Wtraditional",
                    "content": "Warn  about  certain  constructs  that behave differently in traditional and ISO C.  Also\nwarn about ISO C constructs that have no traditional  C  equivalent,  and/or  problematic\nconstructs that should be avoided.\n\n*   Macro  parameters  that  appear  within  string  literals  in  the  macro  body.   In\ntraditional C macro replacement takes place within string literals, but in ISO  C  it\ndoes not.\n\n*   In   traditional   C,  some  preprocessor  directives  did  not  exist.   Traditional\npreprocessors only considered a line to be a directive if the # appeared in column  1\non  the  line.   Therefore  -Wtraditional  warns  about directives that traditional C\nunderstands but ignores because the # does not appear as the first character  on  the\nline.   It  also  suggests  you  hide  directives  like  \"#pragma\"  not understood by\ntraditional C by indenting them.  Some traditional implementations do  not  recognize\n\"#elif\", so this option suggests avoiding it altogether.\n\n*   A function-like macro that appears without arguments.\n\n*   The unary plus operator.\n\n*   The  U  integer  constant  suffix,  or  the  F or L floating-point constant suffixes.\n(Traditional C does support the L suffix on integer constants.)  Note, these suffixes\nappear in macros defined in the system headers  of  most  modern  systems,  e.g.  the\nMIN/MAX  macros  in  \"<limits.h>\".  Use of these macros in user code might normally\nlead to spurious warnings, however GCC's integrated preprocessor has  enough  context\nto avoid warning in these cases.\n\n*   A function declared external in one block and then used after the end of the block.\n\n*   A \"switch\" statement has an operand of type \"long\".\n\n*   A  non-\"static\"  function  declaration follows a \"static\" one.  This construct is not\naccepted by some traditional C compilers.\n\n*   The ISO type of an integer constant has a different  width  or  signedness  from  its\ntraditional  type.   This  warning is only issued if the base of the constant is ten.\nI.e. hexadecimal or octal values, which typically represent  bit  patterns,  are  not\nwarned about.\n\n*   Usage of ISO string concatenation is detected.\n\n*   Initialization of automatic aggregates.\n\n*   Identifier  conflicts  with  labels.   Traditional  C  lacks a separate namespace for\nlabels.\n\n*   Initialization of unions.  If the initializer is zero, the warning is omitted.   This\nis  done  under  the  assumption  that  the  zero  initializer  in  user code appears\nconditioned on e.g. \"STDC\" to avoid missing initializer warnings  and  relies  on\ndefault initialization to zero in the traditional C case.\n\n*   Conversions  by  prototypes  between fixed/floating-point values and vice versa.  The\nabsence of  these  prototypes  when  compiling  with  traditional  C  causes  serious\nproblems.  This is a subset of the possible conversion warnings; for the full set use\n-Wtraditional-conversion.\n\n*   Use  of  ISO  C style function definitions.  This warning intentionally is not issued\nfor prototype declarations or variadic functions because these ISO C features  appear\nin  your code when using libiberty's traditional C compatibility macros, \"PARAMS\" and\n\"VPARAMS\".  This warning is also bypassed for nested functions because  that  feature\nis already a GCC extension and thus not relevant to traditional C compatibility.\n"
                },
                {
                    "name": "-Wtraditional-conversion",
                    "content": "Warn  if a prototype causes a type conversion that is different from what would happen to\nthe same argument in the absence of a prototype.   This  includes  conversions  of  fixed\npoint  to  floating and vice versa, and conversions changing the width or signedness of a\nfixed-point argument except when the same as the default promotion.\n"
                },
                {
                    "name": "-Wdeclaration-after-statement",
                    "content": "Warn when a declaration is found after a statement in a  block.   This  construct,  known\nfrom  C++,  was  introduced  with  ISO  C99  and is by default allowed in GCC.  It is not\nsupported by ISO C90.\n"
                },
                {
                    "name": "-Wshadow",
                    "content": "Warn whenever a local variable or type declaration shadows another  variable,  parameter,\ntype, class member (in C++), or instance variable (in Objective-C) or whenever a built-in\nfunction  is  shadowed.  Note that in C++, the compiler warns if a local variable shadows\nan explicit typedef, but not if it shadows  a  struct/class/enum.   If  this  warning  is\nenabled,   it   includes  also  all  instances  of  local  shadowing.   This  means  that\n-Wno-shadow=local and -Wno-shadow=compatible-local are ignored  when  -Wshadow  is  used.\nSame as -Wshadow=global.\n"
                },
                {
                    "name": "-Wno-shadow-ivar",
                    "content": "Do  not  warn  whenever  a  local variable shadows an instance variable in an Objective-C\nmethod.\n"
                },
                {
                    "name": "-Wshadow=global",
                    "content": "Warn for any shadowing.  Same as -Wshadow.\n"
                },
                {
                    "name": "-Wshadow=local",
                    "content": "Warn when a local variable shadows another local variable or parameter.\n"
                },
                {
                    "name": "-Wshadow=compatible-local",
                    "content": "Warn when a local variable shadows another local variable  or  parameter  whose  type  is\ncompatible  with  that  of the shadowing variable.  In C++, type compatibility here means\nthe type of the shadowing variable can be converted to that  of  the  shadowed  variable.\nThe  creation of this flag (in addition to -Wshadow=local) is based on the idea that when\na local variable shadows another one of incompatible type, it is most likely intentional,\nnot a bug or typo, as shown in the following example:\n\nfor (SomeIterator i = SomeObj.begin(); i != SomeObj.end(); ++i)\n{\nfor (int i = 0; i < N; ++i)\n{\n...\n}\n...\n}\n\nSince the two variable \"i\" in the example above have incompatible  types,  enabling  only\n-Wshadow=compatible-local does not emit a warning.  Because their types are incompatible,\nif a programmer accidentally uses one in place of the other, type checking is expected to\ncatch  that and emit an error or warning.  Use of this flag instead of -Wshadow=local can\npossibly reduce the number of warnings triggered by  intentional  shadowing.   Note  that\nthis also means that shadowing \"const char *i\" by \"char *i\" does not emit a warning.\n\nThis warning is also enabled by -Wshadow=local.\n"
                },
                {
                    "name": "-Wlarger-than=_",
                    "content": "Warn    whenever    an    object    is    defined    whose    size   exceeds   byte-size.\n-Wlarger-than=PTRDIFFMAX is enabled by default.  Warnings controlled by the  option  can\nbe disabled either by specifying byte-size of SIZEMAX or more or by -Wno-larger-than.\n\nAlso  warn  for  calls  to bounded functions such as \"memchr\" or \"strnlen\" that specify a\nbound greater than the largest possible object, which is PTRDIFFMAX  bytes  by  default.\nThese warnings can only be disabled by -Wno-larger-than.\n"
                },
                {
                    "name": "-Wno-larger-than",
                    "content": "Disable  -Wlarger-than=  warnings.  The option is equivalent to -Wlarger-than=SIZEMAX or\nlarger.\n"
                },
                {
                    "name": "-Wframe-larger-than=_",
                    "content": "Warn if the size of  a  function  frame  exceeds  byte-size.   The  computation  done  to\ndetermine  the  stack  frame  size  is  approximate  and  not  conservative.   The actual\nrequirements may be somewhat greater than byte-size even if you do not get a warning.  In\naddition, any space allocated via \"alloca\", variable-length arrays, or related constructs\nis not included by the compiler when determining whether  or  not  to  issue  a  warning.\n-Wframe-larger-than=PTRDIFFMAX is enabled by default.  Warnings controlled by the option\ncan   be   disabled   either   by   specifying  byte-size  of  SIZEMAX  or  more  or  by\n-Wno-frame-larger-than.\n"
                },
                {
                    "name": "-Wno-frame-larger-than",
                    "content": "Disable    -Wframe-larger-than=    warnings.     The    option    is    equivalent     to\n-Wframe-larger-than=SIZEMAX or larger.\n"
                },
                {
                    "name": "-Wfree-nonheap-object",
                    "content": "Warn  when  attempting to deallocate an object that was either not allocated on the heap,\nor by using a pointer that was not returned  from  a  prior  call  to  the  corresponding\nallocation  function.  For example, because the call to \"stpcpy\" returns a pointer to the\nterminating nul character and not to the beginning of the  object,  the  call  to  \"free\"\nbelow is diagnosed.\n\nvoid f (char *p)\n{\np = stpcpy (p, \"abc\");\n// ...\nfree (p);   // warning\n}\n\n-Wfree-nonheap-object is included in -Wall.\n"
                },
                {
                    "name": "-Wstack-usage=_",
                    "content": "Warn  if  the  stack usage of a function might exceed byte-size.  The computation done to\ndetermine the stack usage is conservative.  Any space allocated via  \"alloca\",  variable-\nlength arrays, or related constructs is included by the compiler when determining whether\nor not to issue a warning.\n\nThe message is in keeping with the output of -fstack-usage.\n\n*   If the stack usage is fully static but exceeds the specified amount, it's:\n\nwarning: stack usage is 1120 bytes\n\n*   If the stack usage is (partly) dynamic but bounded, it's:\n\nwarning: stack usage might be 1648 bytes\n\n*   If the stack usage is (partly) dynamic and not bounded, it's:\n\nwarning: stack usage might be unbounded\n\n-Wstack-usage=PTRDIFFMAX  is  enabled by default.  Warnings controlled by the option can\nbe disabled either by specifying byte-size of SIZEMAX or more or by -Wno-stack-usage.\n"
                },
                {
                    "name": "-Wno-stack-usage",
                    "content": "Disable -Wstack-usage= warnings.  The option is equivalent to  -Wstack-usage=SIZEMAX  or\nlarger.\n"
                },
                {
                    "name": "-Wunsafe-loop-optimizations",
                    "content": "Warn  if  the loop cannot be optimized because the compiler cannot assume anything on the\nbounds of the loop indices.  With -funsafe-loop-optimizations warn if the compiler  makes\nsuch assumptions.\n"
                },
                {
                    "name": "-Wno-pedantic-ms-format",
                    "content": "When  used in combination with -Wformat and -pedantic without GNU extensions, this option\ndisables the warnings about non-ISO \"printf\" / \"scanf\"  format  width  specifiers  \"I32\",\n\"I64\", and \"I\" used on Windows targets, which depend on the MS runtime.\n"
                },
                {
                    "name": "-Wpointer-arith",
                    "content": "Warn  about  anything  that depends on the \"size of\" a function type or of \"void\".  GNU C\nassigns these types a size of 1, for convenience in calculations with \"void  *\"  pointers\nand  pointers  to  functions.   In  C++,  warn also when an arithmetic operation involves\n\"NULL\".  This warning is also enabled by -Wpedantic.\n"
                },
                {
                    "name": "-Wno-pointer-compare",
                    "content": "Do not warn if a pointer is compared with a zero character constant.  This usually  means\nthat the pointer was meant to be dereferenced.  For example:\n\nconst char *p = foo ();\nif (p == '\\0')\nreturn 42;\n\nNote that the code above is invalid in C++11.\n\nThis warning is enabled by default.\n"
                },
                {
                    "name": "-Wtsan",
                    "content": "Warn about unsupported features in ThreadSanitizer.\n\nThreadSanitizer   does  not  support  \"std::atomicthreadfence\"  and  can  report  false\npositives.\n\nThis warning is enabled by default.\n"
                },
                {
                    "name": "-Wtype-limits",
                    "content": "Warn if a comparison is always true or always false due to the limited range of the  data\ntype,  but  do  not  warn  for  constant  expressions.   For example, warn if an unsigned\nvariable is compared against zero with \"<\" or \">=\".  This  warning  is  also  enabled  by\n-Wextra.\n"
                },
                {
                    "name": "-Wabsolute-value",
                    "content": "Warn  for calls to standard functions that compute the absolute value of an argument when\na more appropriate standard  function  is  available.   For  example,  calling  abs(3.14)\ntriggers  the  warning  because  the appropriate function to call to compute the absolute\nvalue of a double argument is  \"fabs\".   The  option  also  triggers  warnings  when  the\nargument  in  a  call  to  such  a  function  has  an unsigned type.  This warning can be\nsuppressed with an explicit type cast and it is also enabled by -Wextra.\n"
                },
                {
                    "name": "-Wcomment",
                    "content": ""
                },
                {
                    "name": "-Wcomments",
                    "content": "Warn whenever a comment-start sequence  /*  appears  in  a  /*  comment,  or  whenever  a\nbackslash-newline appears in a // comment.  This warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wtrigraphs",
                    "content": "Warn  if  any  trigraphs  are  encountered  that might change the meaning of the program.\nTrigraphs within comments are not warned about, except  those  that  would  form  escaped\nnewlines.\n\nThis  option  is  implied  by -Wall.  If -Wall is not given, this option is still enabled\nunless trigraphs are enabled.  To get trigraph conversion without warnings, but  get  the\nother -Wall warnings, use -trigraphs -Wall -Wno-trigraphs.\n"
                },
                {
                    "name": "-Wundef",
                    "content": "Warn if an undefined identifier is evaluated in an \"#if\" directive.  Such identifiers are\nreplaced with zero.\n"
                },
                {
                    "name": "-Wexpansion-to-defined",
                    "content": "Warn  whenever  defined  is  encountered  in the expansion of a macro (including the case\nwhere the macro is expanded by an #if directive).  Such  usage  is  not  portable.   This\nwarning is also enabled by -Wpedantic and -Wextra.\n"
                },
                {
                    "name": "-Wunused-macros",
                    "content": "Warn  about  macros  defined  in the main file that are unused.  A macro is used if it is\nexpanded or tested for existence at least once.  The preprocessor also warns if the macro\nhas not been used at the time it is redefined or undefined.\n\nBuilt-in macros, macros defined on the command line, and macros defined in include  files\nare not warned about.\n\nNote:  If a macro is actually used, but only used in skipped conditional blocks, then the\npreprocessor reports it as unused.  To avoid the  warning  in  such  a  case,  you  might\nimprove  the  scope  of  the macro's definition by, for example, moving it into the first\nskipped block.  Alternatively, you could provide a dummy use with something like:\n\n#if defined themacrocausingthewarning\n#endif\n"
                },
                {
                    "name": "-Wno-endif-labels",
                    "content": "Do not warn whenever an \"#else\" or an \"#endif\" are  followed  by  text.   This  sometimes\nhappens in older programs with code of the form\n\n#if FOO\n...\n#else FOO\n...\n#endif FOO\n\nThe second and third \"FOO\" should be in comments.  This warning is on by default.\n"
                },
                {
                    "name": "-Wbad-function-cast",
                    "content": "Warn when a function call is cast to a non-matching type.  For example, warn if a call to\na function returning an integer type is cast to a pointer type.\n"
                },
                {
                    "name": "-Wc90-c99-compat",
                    "content": "Warn  about  features not present in ISO C90, but present in ISO C99.  For instance, warn\nabout use of variable length arrays, \"long long\" type, \"bool\"  type,  compound  literals,\ndesignated  initializers,  and  so on.  This option is independent of the standards mode.\nWarnings are disabled in the expression that follows \"extension\".\n"
                },
                {
                    "name": "-Wc99-c11-compat",
                    "content": "Warn about features not present in ISO C99, but present in ISO C11.  For  instance,  warn\nabout  use  of anonymous structures and unions, \"Atomic\" type qualifier, \"Threadlocal\"\nstorage-class specifier, \"Alignas\" specifier, \"Alignof\"  operator,  \"Generic\"  keyword,\nand  so  on.  This option is independent of the standards mode.  Warnings are disabled in\nthe expression that follows \"extension\".\n"
                },
                {
                    "name": "-Wc11-c2x-compat",
                    "content": "Warn about features not present in ISO C11, but present in ISO C2X.  For  instance,  warn\nabout  omitting the string in \"Staticassert\", use of [[]] syntax for attributes, use of\ndecimal floating-point types, and so on.  This option is  independent  of  the  standards\nmode.  Warnings are disabled in the expression that follows \"extension\".\n"
                },
                {
                    "name": "-Wc++-compat",
                    "content": "Warn  about  ISO C constructs that are outside of the common subset of ISO C and ISO C++,\ne.g. request for implicit conversion from \"void *\" to a pointer to non-\"void\" type.\n"
                },
                {
                    "name": "-Wc++11-compat",
                    "content": "Warn about C++ constructs whose meaning differs between ISO C++ 1998 and  ISO  C++  2011,\ne.g.,  identifiers in ISO C++ 1998 that are keywords in ISO C++ 2011.  This warning turns\non -Wnarrowing and is enabled by -Wall.\n"
                },
                {
                    "name": "-Wc++14-compat",
                    "content": "Warn about C++ constructs whose meaning differs between ISO C++ 2011 and  ISO  C++  2014.\nThis warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wc++17-compat",
                    "content": "Warn  about  C++  constructs whose meaning differs between ISO C++ 2014 and ISO C++ 2017.\nThis warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wc++20-compat",
                    "content": "Warn about C++ constructs whose meaning differs between ISO C++ 2017 and  ISO  C++  2020.\nThis warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wno-c++11-extensions",
                    "content": "Do  not  warn  about C++11 constructs in code being compiled using an older C++ standard.\nEven without this option, some C++11 constructs will only be diagnosed if  -Wpedantic  is\nused.\n"
                },
                {
                    "name": "-Wno-c++14-extensions",
                    "content": "Do  not  warn  about C++14 constructs in code being compiled using an older C++ standard.\nEven without this option, some C++14 constructs will only be diagnosed if  -Wpedantic  is\nused.\n"
                },
                {
                    "name": "-Wno-c++17-extensions",
                    "content": "Do  not  warn  about C++17 constructs in code being compiled using an older C++ standard.\nEven without this option, some C++17 constructs will only be diagnosed if  -Wpedantic  is\nused.\n"
                },
                {
                    "name": "-Wno-c++20-extensions",
                    "content": "Do  not  warn  about C++20 constructs in code being compiled using an older C++ standard.\nEven without this option, some C++20 constructs will only be diagnosed if  -Wpedantic  is\nused.\n"
                },
                {
                    "name": "-Wno-c++23-extensions",
                    "content": "Do  not  warn  about C++23 constructs in code being compiled using an older C++ standard.\nEven without this option, some C++23 constructs will only be diagnosed if  -Wpedantic  is\nused.\n"
                },
                {
                    "name": "-Wcast-qual",
                    "content": "Warn  whenever  a  pointer is cast so as to remove a type qualifier from the target type.\nFor example, warn if a \"const char *\" is cast to an ordinary \"char *\".\n\nAlso warn when making a cast that introduces a type qualifier  in  an  unsafe  way.   For\nexample, casting \"char \" to \"const char \" is unsafe, as in this example:\n\n/* p is char  value.  */\nconst char q = (const char ) p;\n/* Assignment of readonly string to const char * is OK.  */\n*q = \"string\";\n/* Now char pointer points to read-only memory.  */\np = 'b';\n"
                },
                {
                    "name": "-Wcast-align",
                    "content": "Warn  whenever  a  pointer  is  cast  such  that  the required alignment of the target is\nincreased.  For example, warn if a \"char *\" is cast to  an  \"int  *\"  on  machines  where\nintegers can only be accessed at two- or four-byte boundaries.\n"
                },
                {
                    "name": "-Wcast-align=strict",
                    "content": "Warn  whenever  a  pointer  is  cast  such  that  the required alignment of the target is\nincreased.  For example, warn if a \"char *\" is cast to  an  \"int  *\"  regardless  of  the\ntarget machine.\n"
                },
                {
                    "name": "-Wcast-function-type",
                    "content": "Warn  when  a  function  pointer  is cast to an incompatible function pointer.  In a cast\ninvolving function types with  a  variable  argument  list  only  the  types  of  initial\narguments  that  are  provided are considered.  Any parameter of pointer-type matches any\nother pointer-type.  Any benign differences in integral types are ignored, like \"int\" vs.\n\"long\" on ILP32 targets.  Likewise type qualifiers are ignored.  The function type  \"void\n(*)  (void)\"  is  special  and  matches  everything,  which  can be used to suppress this\nwarning.  In a cast involving pointer to member types this  warning  warns  whenever  the\ntype cast is changing the pointer to member type.  This warning is enabled by -Wextra.\n"
                },
                {
                    "name": "-Wwrite-strings",
                    "content": "When compiling C, give string constants the type \"const char[length]\" so that copying the\naddress  of  one  into a non-\"const\" \"char *\" pointer produces a warning.  These warnings\nhelp you find at compile time code that can try to write into a string constant, but only\nif you have been very  careful  about  using  \"const\"  in  declarations  and  prototypes.\nOtherwise,  it  is  just  a  nuisance.  This  is  why we did not make -Wall request these\nwarnings.\n\nWhen compiling C++, warn about the deprecated conversion from string  literals  to  \"char\n*\".  This warning is enabled by default for C++ programs.\n"
                },
                {
                    "name": "-Wclobbered",
                    "content": "Warn  for  variables that might be changed by \"longjmp\" or \"vfork\".  This warning is also\nenabled by -Wextra.\n"
                },
                {
                    "name": "-Wno-complain-wrong-lang",
                    "content": "By default, language front ends complain when a command-line option  is  valid,  but  not\napplicable  to that front end.  This may be disabled with -Wno-complain-wrong-lang, which\nis mostly useful when invoking a single compiler driver for multiple source files written\nin different languages, for example:\n\n$ g++ -fno-rtti a.cc b.f90\n\nThe driver g++ invokes the C++ front end to compile a.cc and the  Fortran  front  end  to\ncompile  b.f90.   The  latter  front  end  diagnoses  f951:  Warning: command-line option\n'-fno-rtti' is valid for C++/D/ObjC++ but not for Fortran, which  may  be  disabled  with\n-Wno-complain-wrong-lang.\n"
                },
                {
                    "name": "-Wconversion",
                    "content": "Warn  for  implicit conversions that may alter a value. This includes conversions between\nreal and integer, like \"abs (x)\" when \"x\" is \"double\";  conversions  between  signed  and\nunsigned, like \"unsigned ui = -1\"; and conversions to smaller types, like \"sqrtf (MPI)\".\nDo  not  warn for explicit casts like \"abs ((int) x)\" and \"ui = (unsigned) -1\", or if the\nvalue is not changed by the conversion like in \"abs (2.0)\".  Warnings  about  conversions\nbetween signed and unsigned integers can be disabled by using -Wno-sign-conversion.\n\nFor  C++,  also  warn for confusing overload resolution for user-defined conversions; and\nconversions that never use a type conversion operator: conversions to  \"void\",  the  same\ntype,  a base class or a reference to them. Warnings about conversions between signed and\nunsigned integers are disabled by default in C++ unless -Wsign-conversion  is  explicitly\nenabled.\n\nWarnings  about  conversion  from  arithmetic  on a small type back to that type are only\ngiven with -Warith-conversion.\n"
                },
                {
                    "name": "-Wdangling-else",
                    "content": "Warn about constructions where there may be confusion to which \"if\" statement  an  \"else\"\nbranch belongs.  Here is an example of such a case:\n\n{\nif (a)\nif (b)\nfoo ();\nelse\nbar ();\n}\n\nIn  C/C++, every \"else\" branch belongs to the innermost possible \"if\" statement, which in\nthis example is \"if (b)\".  This is often not what the programmer expected, as illustrated\nin the above example by indentation the programmer chose.  When there  is  the  potential\nfor  this  confusion, GCC issues a warning when this flag is specified.  To eliminate the\nwarning, add explicit braces around the innermost \"if\" statement so there is no  way  the\n\"else\" can belong to the enclosing \"if\".  The resulting code looks like this:\n\n{\nif (a)\n{\nif (b)\nfoo ();\nelse\nbar ();\n}\n}\n\nThis warning is enabled by -Wparentheses.\n"
                },
                {
                    "name": "-Wdangling-pointer",
                    "content": ""
                },
                {
                    "name": "-Wdangling-pointer=_",
                    "content": "Warn  about  uses  of  pointers  (or  C++  references)  to objects with automatic storage\nduration after their lifetime has ended.   This  includes  local  variables  declared  in\nnested  blocks, compound literals and other unnamed temporary objects.  In addition, warn\nabout storing the address of such objects in escaped pointers.  The warning is enabled at\nall optimization levels but may yield different results with optimization than without.\n\n-Wdangling-pointer=1\nAt level 1 the warning diagnoses only unconditional uses of dangling  pointers.   For\nexample\n\nint f (int c1, int c2, x)\n{\nchar *p = strchr ((char[]){ c1, c2 }, c3);\n// warning: dangling pointer to a compound literal\nreturn p ? *p : 'x';\n}\n\nIn  the  following function the store of the address of the local variable \"x\" in the\nescaped pointer *p also triggers the warning.\n\nvoid g (int p)\n{\nint x = 7;\n// warning: storing the address of a local variable in *p\n*p = &x;\n}\n\n-Wdangling-pointer=2\nAt level 2, in addition to unconditional uses the warning also diagnoses  conditional\nuses of dangling pointers.\n\nFor  example,  because the array a in the following function is out of scope when the\npointer s that was set to point is used, the warning triggers at this level.\n\nvoid f (char *s)\n{\nif (!s)\n{\nchar a[12] = \"tmpname\";\ns = a;\n}\n// warning: dangling pointer to a may be used\nstrcat (s, \".tmp\");\n...\n}\n\n-Wdangling-pointer=2 is included in -Wall.\n"
                },
                {
                    "name": "-Wdate-time",
                    "content": "Warn when macros \"TIME\", \"DATE\" or \"TIMESTAMP\" are encountered as they  might\nprevent bit-wise-identical reproducible compilations.\n"
                },
                {
                    "name": "-Wempty-body",
                    "content": "Warn if an empty body occurs in an \"if\", \"else\" or \"do while\" statement.  This warning is\nalso enabled by -Wextra.\n"
                },
                {
                    "name": "-Wno-endif-labels",
                    "content": "Do not warn about stray tokens after \"#else\" and \"#endif\".\n"
                },
                {
                    "name": "-Wenum-compare",
                    "content": "Warn  about a comparison between values of different enumerated types.  In C++ enumerated\ntype mismatches in conditional expressions are also diagnosed and the warning is  enabled\nby default.  In C this warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wenum-conversion",
                    "content": "Warn  when  a  value of enumerated type is implicitly converted to a different enumerated\ntype.  This warning is enabled by -Wextra in C.\n"
                },
                {
                    "name": "-Wenum-int-mismatch",
                    "content": "Warn about mismatches between an enumerated type and an  integer  type  in  declarations.\nFor example:\n\nenum E { l = -1, z = 0, g = 1 };\nint foo(void);\nenum E foo(void);\n\nIn C, an enumerated type is compatible with \"char\", a signed integer type, or an unsigned\ninteger  type.  However, since the choice of the underlying type of an enumerated type is\nimplementation-defined, such mismatches may  cause  portability  issues.   In  C++,  such\nmismatches are an error.  In C, this warning is enabled by -Wall and -Wc++-compat.\n"
                },
                {
                    "name": "-Wjump-misses-init",
                    "content": "Warn   if   a  \"goto\"  statement  or  a  \"switch\"  statement  jumps  forward  across  the\ninitialization of a variable, or jumps backward to a label after the  variable  has  been\ninitialized.   This  only  warns  about  variables  that  are  initialized  when they are\ndeclared.  This warning is only supported for C and Objective-C;  in  C++  this  sort  of\nbranch is an error in any case.\n\n-Wjump-misses-init   is   included   in  -Wc++-compat.   It  can  be  disabled  with  the\n-Wno-jump-misses-init option.\n"
                },
                {
                    "name": "-Wsign-compare",
                    "content": "Warn when a comparison between signed and unsigned  values  could  produce  an  incorrect\nresult  when  the  signed  value  is converted to unsigned.  In C++, this warning is also\nenabled by -Wall.  In C, it is also enabled by -Wextra.\n"
                },
                {
                    "name": "-Wsign-conversion",
                    "content": "Warn for implicit conversions that  may  change  the  sign  of  an  integer  value,  like\nassigning  a  signed integer expression to an unsigned integer variable. An explicit cast\nsilences the warning. In C, this option is enabled also by -Wconversion.\n"
                },
                {
                    "name": "-Wfloat-conversion",
                    "content": "Warn for implicit conversions that reduce the precision of a real value.   This  includes\nconversions  from real to integer, and from higher precision real to lower precision real\nvalues.  This option is also enabled by -Wconversion.\n"
                },
                {
                    "name": "-Wno-scalar-storage-order",
                    "content": "Do not warn on suspicious constructs involving reverse scalar storage order.\n"
                },
                {
                    "name": "-Wsizeof-array-div",
                    "content": "Warn about divisions of two sizeof operators when the first one is applied  to  an  array\nand  the  divisor  does  not  equal  the  size of the array element.  In such a case, the\ncomputation will not yield the number of elements in the array, which is likely what  the\nuser intended.  This warning warns e.g. about\n\nint fn ()\n{\nint arr[10];\nreturn sizeof (arr) / sizeof (short);\n}\n\nThis warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wsizeof-pointer-div",
                    "content": "Warn  for  suspicious divisions of two sizeof expressions that divide the pointer size by\nthe element size, which is the usual way to compute the array size  but  won't  work  out\ncorrectly  with pointers.  This warning warns e.g. about \"sizeof (ptr) / sizeof (ptr[0])\"\nif \"ptr\" is not an array, but a pointer.  This warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wsizeof-pointer-memaccess",
                    "content": "Warn for suspicious length parameters to certain string and memory built-in functions  if\nthe  argument  uses  \"sizeof\".   This  warning  triggers for example for \"memset (ptr, 0,\nsizeof (ptr));\" if \"ptr\" is not an array, but a pointer, and suggests a possible fix,  or\nabout  \"memcpy (&foo, ptr, sizeof (&foo));\".  -Wsizeof-pointer-memaccess also warns about\ncalls to bounded string copy functions like \"strncat\" or \"strncpy\" that  specify  as  the\nbound  a \"sizeof\" expression of the source array.  For example, in the following function\nthe call to \"strncat\" specifies the size of the source string  as  the  bound.   That  is\nalmost certainly a mistake and so the call is diagnosed.\n\nvoid makefile (const char *name)\n{\nchar path[PATHMAX];\nstrncpy (path, name, sizeof path - 1);\nstrncat (path, \".text\", sizeof \".text\");\n...\n}\n\nThe -Wsizeof-pointer-memaccess option is enabled by -Wall.\n"
                },
                {
                    "name": "-Wno-sizeof-array-argument",
                    "content": "Do  not  warn when the \"sizeof\" operator is applied to a parameter that is declared as an\narray in a function definition.  This warning  is  enabled  by  default  for  C  and  C++\nprograms.\n"
                },
                {
                    "name": "-Wmemset-elt-size",
                    "content": "Warn  for  suspicious  calls  to  the  \"memset\"  built-in function, if the first argument\nreferences an array, and the third argument is a number equal to the number of  elements,\nbut  not  equal  to  the  size  of the array in memory.  This indicates that the user has\nomitted a multiplication by the element size.  This warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wmemset-transposed-args",
                    "content": "Warn for suspicious calls to the \"memset\" built-in function where the second argument  is\nnot zero and the third argument is zero.  For example, the call \"memset (buf, sizeof buf,\n0)\" is diagnosed because \"memset (buf, 0, sizeof buf)\" was meant instead.  The diagnostic\nis  only  emitted  if  the  third  argument  is  a  literal zero.  Otherwise, if it is an\nexpression that is folded to zero, or a cast of zero to some type, it is far less  likely\nthat  the  arguments  have  been  mistakenly  transposed and no warning is emitted.  This\nwarning is enabled by -Wall.\n"
                },
                {
                    "name": "-Waddress",
                    "content": "Warn about suspicious uses of address expressions. These include comparing the address of\na function or a declared object to the null pointer constant such as in\n\nvoid f (void);\nvoid g (void)\n{\nif (!f)   // warning: expression evaluates to false\nabort ();\n}\n\ncomparisons of a pointer to a string literal, such as in\n\nvoid f (const char *x)\n{\nif (x == \"abc\")   // warning: expression evaluates to false\nputs (\"equal\");\n}\n\nand tests of the results of pointer addition or subtraction for equality to null, such as\nin\n\nvoid f (const int *p, int i)\n{\nreturn p + i == NULL;\n}\n\nSuch uses typically indicate a programmer  error:  the  address  of  most  functions  and\nobjects necessarily evaluates to true (the exception are weak symbols), so their use in a\nconditional  might  indicate  missing  parentheses  in  a  function  call  or  a  missing\ndereference in an array expression.  The subset of the warning for object pointers can be\nsuppressed by casting the pointer operand to  an  integer  type  such  as  \"intptrt\"  or\n\"uintptrt\".   Comparisons against string literals result in unspecified behavior and are\nnot portable, and suggest the intent was to call \"strcmp\".  The warning is suppressed  if\nthe suspicious expression is the result of macro expansion.  -Waddress warning is enabled\nby -Wall.\n"
                },
                {
                    "name": "-Wno-address-of-packed-member",
                    "content": "Do  not warn when the address of packed member of struct or union is taken, which usually\nresults in an unaligned pointer value.  This is enabled by default.\n"
                },
                {
                    "name": "-Wlogical-op",
                    "content": "Warn about suspicious uses of logical operators  in  expressions.   This  includes  using\nlogical  operators  in contexts where a bit-wise operator is likely to be expected.  Also\nwarns when the operands of a logical operator are the same:\n\nextern int a;\nif (a < 0 && a < 0) { ... }\n"
                },
                {
                    "name": "-Wlogical-not-parentheses",
                    "content": "Warn about logical not used on the left hand side operand of a comparison.   This  option\ndoes not warn if the right operand is considered to be a boolean expression.  Its purpose\nis to detect suspicious code like the following:\n\nint a;\n...\nif (!a > 1) { ... }\n\nIt is possible to suppress the warning by wrapping the LHS into parentheses:\n\nif ((!a) > 1) { ... }\n\nThis warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Waggregate-return",
                    "content": "Warn  if  any  functions  that  return  structures  or unions are defined or called.  (In\nlanguages where you can return an array, this also elicits a warning.)\n"
                },
                {
                    "name": "-Wno-aggressive-loop-optimizations",
                    "content": "Warn if in a loop with constant number  of  iterations  the  compiler  detects  undefined\nbehavior in some statement during one or more of the iterations.\n"
                },
                {
                    "name": "-Wno-attributes",
                    "content": "Do  not  warn  if an unexpected \"attribute\" is used, such as unrecognized attributes,\nfunction attributes applied to variables, etc.  This does not stop errors  for  incorrect\nuse of supported attributes.\n\nAdditionally,  using  -Wno-attributes=, it is possible to suppress warnings about unknown\nscoped attributes (in C++11 and C2X).  For example, -Wno-attributes=vendor::attr disables\nwarning about the following declaration:\n\n[[vendor::attr]] void f();\n\nIt is also possible to  disable  warning  about  all  attributes  in  a  namespace  using\n-Wno-attributes=vendor:: which prevents warning about both of these declarations:\n\n[[vendor::safe]] void f();\n[[vendor::unsafe]] void f2();\n\nNote that -Wno-attributes= does not imply -Wno-attributes.\n"
                },
                {
                    "name": "-Wno-builtin-declaration-mismatch",
                    "content": "Warn  if  a  built-in  function  is  declared with an incompatible signature or as a non-\nfunction, or when a built-in function declared with  a  type  that  does  not  include  a\nprototype  is  called  with arguments whose promoted types do not match those expected by\nthe function.  When -Wextra is specified, also warn when a built-in function  that  takes\narguments is declared without a prototype.  The -Wbuiltin-declaration-mismatch warning is\nenabled  by  default.   To  avoid the warning include the appropriate header to bring the\nprototypes of built-in functions into scope.\n\nFor example, the call to \"memset\" below is diagnosed by the warning because the  function\nexpects  a  value  of  type  \"sizet\"  as its argument but the type of 32 is \"int\".  With\n-Wextra, the declaration of the function is diagnosed as well.\n\nextern void* memset ();\nvoid f (void *d)\n{\nmemset (d, '\\0', 32);\n}\n"
                },
                {
                    "name": "-Wno-builtin-macro-redefined",
                    "content": "Do not warn if certain built-in macros  are  redefined.   This  suppresses  warnings  for\nredefinition of \"TIMESTAMP\", \"TIME\", \"DATE\", \"FILE\", and \"BASEFILE\".\n"
                },
                {
                    "name": "-Wstrict-prototypes",
                    "content": "Warn  if  a  function  is declared or defined without specifying the argument types.  (An\nold-style function definition is permitted without a warning if preceded by a declaration\nthat specifies the argument types.)\n"
                },
                {
                    "name": "-Wold-style-declaration",
                    "content": "Warn for obsolescent usages, according to the C Standard, in a declaration. For  example,\nwarn if storage-class specifiers like \"static\" are not the first things in a declaration.\nThis warning is also enabled by -Wextra.\n"
                },
                {
                    "name": "-Wold-style-definition",
                    "content": "Warn  if an old-style function definition is used.  A warning is given even if there is a\nprevious prototype.  A definition using () is not considered an old-style  definition  in\nC2X mode, because it is equivalent to (void) in that case, but is considered an old-style\ndefinition for older standards.\n"
                },
                {
                    "name": "-Wmissing-parameter-type",
                    "content": "A function parameter is declared without a type specifier in K&R-style functions:\n\nvoid foo(bar) { }\n\nThis warning is also enabled by -Wextra.\n"
                },
                {
                    "name": "-Wmissing-prototypes",
                    "content": "Warn  if  a  global  function  is defined without a previous prototype declaration.  This\nwarning is issued even if the definition itself provides a prototype.  Use this option to\ndetect global functions that do not have a matching prototype  declaration  in  a  header\nfile.   This  option  is  not  valid  for  C++  because all function declarations provide\nprototypes and a non-matching declaration declares an overload rather than conflict  with\nan  earlier  declaration.   Use  -Wmissing-declarations to detect missing declarations in\nC++.\n"
                },
                {
                    "name": "-Wmissing-declarations",
                    "content": "Warn if a global function is defined without a previous declaration.  Do so even  if  the\ndefinition  itself provides a prototype.  Use this option to detect global functions that\nare not declared in header files.  In C,  no  warnings  are  issued  for  functions  with\nprevious   non-prototype   declarations;   use  -Wmissing-prototypes  to  detect  missing\nprototypes.  In C++, no warnings  are  issued  for  function  templates,  or  for  inline\nfunctions, or for functions in anonymous namespaces.\n"
                },
                {
                    "name": "-Wmissing-field-initializers",
                    "content": "Warn  if  a  structure's initializer has some fields missing.  For example, the following\ncode causes such a warning, because \"x.h\" is implicitly zero:\n\nstruct s { int f, g, h; };\nstruct s x = { 3, 4 };\n\nThis option does not warn about designated initializers, so  the  following  modification\ndoes not trigger a warning:\n\nstruct s { int f, g, h; };\nstruct s x = { .f = 3, .g = 4 };\n\nIn C this option does not warn about the universal zero initializer { 0 }:\n\nstruct s { int f, g, h; };\nstruct s x = { 0 };\n\nLikewise, in C++ this option does not warn about the empty { } initializer, for example:\n\nstruct s { int f, g, h; };\ns x = { };\n\nThis warning is included in -Wextra.  To get other -Wextra warnings without this one, use\n-Wextra -Wno-missing-field-initializers.\n"
                },
                {
                    "name": "-Wno-missing-requires",
                    "content": "By  default,  the  compiler  warns  about  a  concept-id  appearing  as  a  C++20 simple-\nrequirement:\n\nbool satisfied = requires { C<T> };\n\nHere satisfied will be true if C<T> is a  valid  expression,  which  it  is  for  all  T.\nPresumably the user meant to write\n\nbool satisfied = requires { requires C<T> };\n\nso satisfied is only true if concept C is satisfied for type T.\n\nThis warning can be disabled with -Wno-missing-requires.\n"
                },
                {
                    "name": "-Wno-missing-template-keyword",
                    "content": "The  member  access tokens ., -> and :: must be followed by the \"template\" keyword if the\nparent object is dependent and the member being named is a template.\n\ntemplate <class X>\nvoid DoStuff (X x)\n{\nx.template DoSomeOtherStuff<X>(); // Good.\nx.DoMoreStuff<X>(); // Warning, x is dependent.\n}\n\nIn rare cases it is possible to get false positives. To silence this, wrap the expression\nin parentheses. For example, the following is treated as a template, even where m  and  N\nare integers:\n\nvoid NotATemplate (myclass t)\n{\nint N = 5;\n\nbool test = t.m < N > (0); // Treated as a template.\ntest = (t.m < N) > (0); // Same meaning, but not treated as a template.\n}\n\nThis warning can be disabled with -Wno-missing-template-keyword.\n"
                },
                {
                    "name": "-Wno-multichar",
                    "content": "Do  not warn if a multicharacter constant ('FOOF') is used.  Usually they indicate a typo\nin the user's code, as they have implementation-defined values, and should not be used in\nportable code.\n"
                },
                {
                    "name": "-Wnormalized=",
                    "content": "In ISO C and ISO C++, two identifiers are different if they are  different  sequences  of\ncharacters.  However, sometimes when characters outside the basic ASCII character set are\nused,  you  can  have  two  different  character  sequences that look the same.  To avoid\nconfusion, the ISO 10646 standard sets out some normalization rules  which  when  applied\nensure  that two sequences that look the same are turned into the same sequence.  GCC can\nwarn you if you are using identifiers that have not been normalized; this option controls\nthat warning.\n\nThere are four levels of warning supported by  GCC.   The  default  is  -Wnormalized=nfc,\nwhich  warns  about any identifier that is not in the ISO 10646 \"C\" normalized form, NFC.\nNFC is the recommended form for most uses.  It is equivalent to -Wnormalized.\n\nUnfortunately, there are some characters allowed in identifiers by  ISO  C  and  ISO  C++\nthat,  when  turned into NFC, are not allowed in identifiers.  That is, there's no way to\nuse these symbols in portable ISO C  or  C++  and  have  all  your  identifiers  in  NFC.\n-Wnormalized=id  suppresses  the  warning  for these characters.  It is hoped that future\nversions of the standards involved will correct this, which is why this option is not the\ndefault.\n\nYou can switch the warning  off  for  all  characters  by  writing  -Wnormalized=none  or\n-Wno-normalized.   You  should  only  do  this  if you are using some other normalization\nscheme (like \"D\"), because otherwise you  can  easily  create  bugs  that  are  literally\nimpossible to see.\n\nSome  characters  in ISO 10646 have distinct meanings but look identical in some fonts or\ndisplay methodologies,  especially  once  formatting  has  been  applied.   For  instance\n\"\\u207F\",  \"SUPERSCRIPT  LATIN SMALL LETTER N\", displays just like a regular \"n\" that has\nbeen placed in a superscript.  ISO 10646 defines the NFKC normalization scheme to convert\nall these into a standard form as well, and GCC warns if your code is not in NFKC if  you\nuse -Wnormalized=nfkc.  This warning is comparable to warning about every identifier that\ncontains  the  letter  O because it might be confused with the digit 0, and so is not the\ndefault, but may be useful as a local coding convention if  the  programming  environment\ncannot be fixed to display these characters distinctly.\n"
                },
                {
                    "name": "-Wno-attribute-warning",
                    "content": "Do not warn about usage of functions declared with \"warning\" attribute.  By default, this\nwarning  is  enabled.   -Wno-attribute-warning  can  be  used  to  disable the warning or\n-Wno-error=attribute-warning can be used to disable the error when compiled with  -Werror\nflag.\n"
                },
                {
                    "name": "-Wno-deprecated",
                    "content": "Do not warn about usage of deprecated features.\n"
                },
                {
                    "name": "-Wno-deprecated-declarations",
                    "content": "Do  not  warn about uses of functions, variables, and types marked as deprecated by using\nthe \"deprecated\" attribute.\n"
                },
                {
                    "name": "-Wno-overflow",
                    "content": "Do not warn about compile-time overflow in constant expressions.\n"
                },
                {
                    "name": "-Wno-odr",
                    "content": "Warn about One Definition Rule violations  during  link-time  optimization.   Enabled  by\ndefault.\n"
                },
                {
                    "name": "-Wopenacc-parallelism",
                    "content": "Warn about potentially suboptimal choices related to OpenACC parallelism.\n"
                },
                {
                    "name": "-Wopenmp-simd",
                    "content": "Warn  if  the vectorizer cost model overrides the OpenMP simd directive set by user.  The\n-fsimd-cost-model=unlimited option can be used to relax the cost model.\n"
                },
                {
                    "name": "-Woverride-init",
                    "content": "Warn if an initialized field without side effects is  overridden  when  using  designated\ninitializers.\n\nThis warning is included in -Wextra.  To get other -Wextra warnings without this one, use\n-Wextra -Wno-override-init.\n"
                },
                {
                    "name": "-Wno-override-init-side-effects",
                    "content": "Do not warn if an initialized field with side effects is overridden when using designated\ninitializers.  This warning is enabled by default.\n"
                },
                {
                    "name": "-Wpacked",
                    "content": "Warn if a structure is given the packed attribute, but the packed attribute has no effect\non  the  layout  or size of the structure.  Such structures may be mis-aligned for little\nbenefit.  For instance, in this code, the variable \"f.x\" in \"struct  bar\"  is  misaligned\neven though \"struct bar\" does not itself have the packed attribute:\n\nstruct foo {\nint x;\nchar a, b, c, d;\n} attribute((packed));\nstruct bar {\nchar z;\nstruct foo f;\n};\n"
                },
                {
                    "name": "-Wnopacked-bitfield-compat",
                    "content": "The  4.1,  4.2  and 4.3 series of GCC ignore the \"packed\" attribute on bit-fields of type\n\"char\".  This was fixed in GCC 4.4  but  the  change  can  lead  to  differences  in  the\nstructure  layout.   GCC  informs  you when the offset of such a field has changed in GCC\n4.4.  For example there is no longer a 4-bit padding between field \"a\" and  \"b\"  in  this\nstructure:\n\nstruct foo\n{\nchar a:4;\nchar b:8;\n} attribute ((packed));\n\nThis  warning  is  enabled  by  default.  Use -Wno-packed-bitfield-compat to disable this\nwarning.\n"
                },
                {
                    "name": "-Wpacked-not-aligned",
                    "content": "Warn if a structure field with explicitly specified alignment in a packed struct or union\nis misaligned.  For example, a warning will be issued  on  \"struct  S\",  like,  \"warning:\nalignment 1 of 'struct S' is less than 8\", in this code:\n\nstruct attribute ((aligned (8))) S8 { char a[8]; };\nstruct attribute ((packed)) S {\nstruct S8 s8;\n};\n\nThis warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wpadded",
                    "content": "Warn  if  padding is included in a structure, either to align an element of the structure\nor to align the whole structure.  Sometimes when this happens it is possible to rearrange\nthe fields of the structure to reduce the padding and so make the structure smaller.\n"
                },
                {
                    "name": "-Wredundant-decls",
                    "content": "Warn if anything is declared more than once in  the  same  scope,  even  in  cases  where\nmultiple declaration is valid and changes nothing.\n"
                },
                {
                    "name": "-Wrestrict",
                    "content": "Warn  when  an  object  referenced  by  a  \"restrict\"-qualified  parameter (or, in C++, a\n\"restrict\"-qualified parameter) is aliased by another argument, or when copies  between\nsuch  objects  overlap.  For example, the call to the \"strcpy\" function below attempts to\ntruncate the string by replacing its initial characters with  the  last  four.   However,\nbecause  the call writes the terminating NUL into \"a[4]\", the copies overlap and the call\nis diagnosed.\n\nvoid foo (void)\n{\nchar a[] = \"abcd1234\";\nstrcpy (a, a + 4);\n...\n}\n\nThe -Wrestrict option detects some instances of simple overlap even without  optimization\nbut works best at -O2 and above.  It is included in -Wall.\n"
                },
                {
                    "name": "-Wnested-externs",
                    "content": "Warn if an \"extern\" declaration is encountered within a function.\n"
                },
                {
                    "name": "-Winline",
                    "content": "Warn  if a function that is declared as inline cannot be inlined.  Even with this option,\nthe compiler does not warn about failures to inline functions declared in system headers.\n\nThe compiler uses a variety of heuristics  to  determine  whether  or  not  to  inline  a\nfunction.   For  example,  the compiler takes into account the size of the function being\ninlined and the amount of inlining that has already been done in  the  current  function.\nTherefore,  seemingly  insignificant changes in the source program can cause the warnings\nproduced by -Winline to appear or disappear.\n"
                },
                {
                    "name": "-Winterference-size",
                    "content": "Warn about use of C++17 \"std::hardwaredestructiveinterferencesize\" without  specifying\nits  value  with  --param  destructive-interference-size.   Also  warn about questionable\nvalues for that option.\n\nThis variable is intended to be used for controlling class layout, to avoid false sharing\nin concurrent code:\n\nstruct independentfields {\nalignas(std::hardwaredestructiveinterferencesize)\nstd::atomic<int> one;\nalignas(std::hardwaredestructiveinterferencesize)\nstd::atomic<int> two;\n};\n\nHere one and two are intended to be far enough apart that stores  to  one  won't  require\naccesses to the other to reload the cache line.\n\nBy  default, --param destructive-interference-size and --param constructive-interference-\nsize are set based on the current -mtune option, typically to the L1 cache line size  for\nthe  particular  target CPU, sometimes to a range if tuning for a generic target.  So all\ntranslation units that depend on ABI compatibility for the use of these variables must be\ncompiled with the same -mtune (or -mcpu).\n\nIf ABI stability is important, such as if the use is in  a  header  for  a  library,  you\nshould  probably not use the hardware interference size variables at all.  Alternatively,\nyou can force a particular value with --param.\n\nIf you are confident that your use of the variable does not affect ABI outside  a  single\nbuild of your project, you can turn off the warning with -Wno-interference-size.\n"
                },
                {
                    "name": "-Wint-in-bool-context",
                    "content": "Warn  for  suspicious  use  of  integer values where boolean values are expected, such as\nconditional expressions (?:) using non-boolean integer constants in boolean context, like\n\"if (a <= b ? 2 : 3)\".  Or left shifting of signed integers in boolean context, like \"for\n(a = 0; 1 << a; a++);\".  Likewise for all kinds of multiplications regardless of the data\ntype.  This warning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wno-int-to-pointer-cast",
                    "content": "Suppress warnings from casts to pointer type of an integer of a different size.  In  C++,\ncasting to a pointer type of smaller size is an error. Wint-to-pointer-cast is enabled by\ndefault.\n"
                },
                {
                    "name": "-Wno-pointer-to-int-cast",
                    "content": "Suppress warnings from casts from a pointer to an integer type of a different size.\n"
                },
                {
                    "name": "-Winvalid-pch",
                    "content": "Warn if a precompiled header is found in the search path but cannot be used.\n"
                },
                {
                    "name": "-Winvalid-utf8",
                    "content": "Warn  if an invalid UTF-8 character is found.  This warning is on by default for C++23 if\n-finput-charset=UTF-8 is used and turned into error with -pedantic-errors.\n"
                },
                {
                    "name": "-Wno-unicode",
                    "content": "Don't diagnose invalid forms of delimited or named escape sequences which are treated  as\nseparate tokens.  Wunicode is enabled by default.\n"
                },
                {
                    "name": "-Wlong-long",
                    "content": "Warn  if \"long long\" type is used.  This is enabled by either -Wpedantic or -Wtraditional\nin ISO C90 and C++98 modes.  To inhibit the warning messages, use -Wno-long-long.\n"
                },
                {
                    "name": "-Wvariadic-macros",
                    "content": "Warn if variadic macros are used in ISO C90 mode, or if the GNU alternate syntax is  used\nin  ISO C99 mode.  This is enabled by either -Wpedantic or -Wtraditional.  To inhibit the\nwarning messages, use -Wno-variadic-macros.\n"
                },
                {
                    "name": "-Wno-varargs",
                    "content": "Do not warn upon questionable usage of the macros used to handle variable arguments  like\n\"vastart\".  These warnings are enabled by default.\n"
                },
                {
                    "name": "-Wvector-operation-performance",
                    "content": "Warn  if  vector  operation is not implemented via SIMD capabilities of the architecture.\nMainly  useful  for  the  performance  tuning.   Vector  operation  can  be   implemented\n\"piecewise\",  which means that the scalar operation is performed on every vector element;\n\"in parallel\", which means that the vector operation  is  implemented  using  scalars  of\nwider type, which normally is more performance efficient; and \"as a single scalar\", which\nmeans that vector fits into a scalar type.\n"
                },
                {
                    "name": "-Wvla",
                    "content": "Warn  if  a  variable-length array is used in the code.  -Wno-vla prevents the -Wpedantic\nwarning of the variable-length array.\n"
                },
                {
                    "name": "-Wvla-larger-than=_",
                    "content": "If this option is used, the compiler warns for  declarations  of  variable-length  arrays\nwhose  size  is either unbounded, or bounded by an argument that allows the array size to\nexceed byte-size bytes.  This is similar to how -Walloca-larger-than=byte-size works, but\nwith variable-length arrays.\n\nNote that GCC may optimize small variable-length arrays  of  a  known  value  into  plain\narrays, so this warning may not get triggered for such arrays.\n\n-Wvla-larger-than=PTRDIFFMAX  is enabled by default but is typically only effective when\n-ftree-vrp is active (default for -O2 and above).\n\nSee also -Walloca-larger-than=byte-size.\n"
                },
                {
                    "name": "-Wno-vla-larger-than",
                    "content": "Disable    -Wvla-larger-than=    warnings.     The    option     is     equivalent     to\n-Wvla-larger-than=SIZEMAX or larger.\n"
                },
                {
                    "name": "-Wvla-parameter",
                    "content": "Warn about redeclarations of functions involving arguments of Variable Length Array types\nof  inconsistent  kinds  or  forms, and enable the detection of out-of-bounds accesses to\nsuch parameters by warnings such as -Warray-bounds.\n\nIf the first function declaration uses the VLA form the bound specified in the  array  is\nassumed  to  be  the  minimum  number of elements expected to be provided in calls to the\nfunction and the maximum number of elements accessed by it.  Failing to provide arguments\nof sufficient size or  accessing  more  than  the  maximum  number  of  elements  may  be\ndiagnosed.\n\nFor  example, the warning triggers for the following redeclarations because the first one\nallows an array of any size to be passed to \"f\" while the second one specifies  that  the\narray  argument  must  have  at  least  \"n\"  elements.  In addition, calling \"f\" with the\nassociated VLA bound parameter in excess of the actual VLA bound triggers  a  warning  as\nwell.\n\nvoid f (int n, int[n]);\n// warning: argument 2 previously declared as a VLA\nvoid f (int, int[]);\n\nvoid g (int n)\n{\nif (n > 4)\nreturn;\nint a[n];\n// warning: access to a by f may be out of bounds\nf (sizeof a, a);\n...\n}\n\n-Wvla-parameter is included in -Wall.  The -Warray-parameter option triggers warnings for\nsimilar problems involving ordinary array arguments.\n"
                },
                {
                    "name": "-Wvolatile-register-var",
                    "content": "Warn if a register variable is declared volatile.  The volatile modifier does not inhibit\nall  optimizations  that  may  eliminate reads and/or writes to register variables.  This\nwarning is enabled by -Wall.\n"
                },
                {
                    "name": "-Wxor-used-as-pow",
                    "content": "Warn about uses of \"^\", the exclusive or  operator,  where  it  appears  the  user  meant\nexponentiation.   Specifically, the warning occurs when the left-hand side is the decimal\nconstant 2 or 10 and the right-hand side is also a decimal constant.\n\nIn C and C++, \"^\" means exclusive or, whereas in some other languages (e.g. TeX and  some\nversions of BASIC) it means exponentiation.\n\nThis warning is enabled by default.  It can be silenced by converting one of the operands\nto hexadecimal.\n"
                },
                {
                    "name": "-Wdisabled-optimization",
                    "content": "Warn  if  a  requested  optimization  pass  is disabled.  This warning does not generally\nindicate that there is anything wrong with your code;  it  merely  indicates  that  GCC's\noptimizers  are  unable  to handle the code effectively.  Often, the problem is that your\ncode is too big or too complex; GCC refuses to optimize programs  when  the  optimization\nitself is likely to take inordinate amounts of time.\n"
                },
                {
                    "name": "-Wpointer-sign",
                    "content": "Warn  for  pointer argument passing or assignment with different signedness.  This option\nis only supported for C and Objective-C.  It is implied by -Wall and by -Wpedantic, which\ncan be disabled with -Wno-pointer-sign.\n"
                },
                {
                    "name": "-Wstack-protector",
                    "content": "This option is only active when -fstack-protector is active.  It  warns  about  functions\nthat are not protected against stack smashing.\n"
                },
                {
                    "name": "-Woverlength-strings",
                    "content": "Warn  about  string constants that are longer than the \"minimum maximum\" length specified\nin the C standard.  Modern compilers generally  allow  string  constants  that  are  much\nlonger  than  the standard's minimum limit, but very portable programs should avoid using\nlonger strings.\n\nThe limit applies after string constant concatenation, and does not  count  the  trailing\nNUL.   In  C90,  the limit was 509 characters; in C99, it was raised to 4095.  C++98 does\nnot specify a normative minimum maximum, so we do not diagnose overlength strings in C++.\n\nThis option is implied by -Wpedantic, and can be disabled with -Wno-overlength-strings.\n"
                },
                {
                    "name": "-Wunsuffixed-float-constants",
                    "content": "Issue a warning for any floating constant  that  does  not  have  a  suffix.   When  used\ntogether  with  -Wsystem-headers  it  warns  about such constants in system header files.\nThis can be useful when preparing code to use  with  the  \"FLOATCONSTDECIMAL64\"  pragma\nfrom the decimal floating-point extension to C99.\n"
                },
                {
                    "name": "-Wno-lto-type-mismatch",
                    "content": "During  the  link-time  optimization,  do  not  warn  about  type  mismatches  in  global\ndeclarations from different compilation units.  Requires -flto to be enabled.  Enabled by\ndefault.\n"
                },
                {
                    "name": "-Wno-designated-init",
                    "content": "Suppress warnings when a positional initializer is used to initialize  a  structure  that\nhas been marked with the \"designatedinit\" attribute.\n"
                },
                {
                    "name": "Options That Control Static Analysis",
                    "content": ""
                },
                {
                    "name": "-fanalyzer",
                    "content": "This  option  enables  an  static  analysis of program flow which looks for \"interesting\"\ninterprocedural paths through the code, and issues warnings for problems found on them.\n\nThis analysis is much more expensive than other GCC warnings.\n\nIn technical terms, it performs coverage-guided symbolic  execution  of  the  code  being\ncompiled.   It  is  neither  sound  nor  complete:  it can have false positives and false\nnegatives.  It is a bug-finding tool, rather than a tool for proving program correctness.\n\nThe analyzer is only suitable for use on C code in this release.\n\nEnabling this option effectively enables the following warnings:\n\n-Wanalyzer-allocation-size     -Wanalyzer-deref-before-check     -Wanalyzer-double-fclose\n-Wanalyzer-double-free                            -Wanalyzer-exposure-through-output-file\n-Wanalyzer-exposure-through-uninit-copy                -Wanalyzer-fd-access-mode-mismatch\n-Wanalyzer-fd-double-close         -Wanalyzer-fd-leak        -Wanalyzer-fd-phase-mismatch\n-Wanalyzer-fd-type-mismatch -Wanalyzer-fd-use-after-close -Wanalyzer-fd-use-without-check\n-Wanalyzer-file-leak    -Wanalyzer-free-of-non-heap    -Wanalyzer-imprecise-fp-arithmetic\n-Wanalyzer-infinite-recursion     -Wanalyzer-jump-through-null     -Wanalyzer-malloc-leak\n-Wanalyzer-mismatching-deallocation -Wanalyzer-null-argument  -Wanalyzer-null-dereference\n-Wanalyzer-out-of-bounds                                -Wanalyzer-possible-null-argument\n-Wanalyzer-possible-null-dereference                        -Wanalyzer-putenv-of-auto-var\n-Wanalyzer-shift-count-negative                           -Wanalyzer-shift-count-overflow\n-Wanalyzer-stale-setjmp-buffer               -Wanalyzer-unsafe-call-within-signal-handler\n-Wanalyzer-use-after-free                  -Wanalyzer-use-of-pointer-in-stale-stack-frame\n-Wanalyzer-use-of-uninitialized-value                     -Wanalyzer-va-arg-type-mismatch\n-Wanalyzer-va-list-exhausted  -Wanalyzer-va-list-leak -Wanalyzer-va-list-use-after-va-end\n-Wanalyzer-write-to-const -Wanalyzer-write-to-string-literal\n\nThis option is only available if GCC was configured with analyzer support enabled.\n"
                },
                {
                    "name": "-Wanalyzer-too-complex",
                    "content": "If -fanalyzer is enabled, the analyzer uses various heuristics to attempt to explore  the\ncontrol  flow  and  data  flow  in the program, but these can be defeated by sufficiently\ncomplicated code.\n\nBy default, the analysis silently stops if the code is too complicated for  the  analyzer\nto  fully  explore  and  it reaches an internal limit.  The -Wanalyzer-too-complex option\nwarns if this occurs.\n"
                },
                {
                    "name": "-Wno-analyzer-allocation-size",
                    "content": "This  warning   requires   -fanalyzer,   which   enables   it;   to   disable   it,   use\n-Wno-analyzer-allocation-size.\n\nThis  diagnostic  warns  for  paths  through  the  code in which a pointer to a buffer is\nassigned to point at a buffer with a size that is not a multiple of \"sizeof (*pointer)\".\n\nSee        CWE-131:       Incorrect       Calculation        of        Buffer        Size\n(\"https://cwe.mitre.org/data/definitions/131.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-deref-before-check",
                    "content": "This  warning requires -fanalyzer, which enables it; use -Wno-analyzer-deref-before-check\nto disable it.\n\nThis diagnostic warns for paths through the code in which a pointer is checked for \"NULL\"\n*after* it has already been dereferenced, suggesting that the  pointer  could  have  been\nNULL.   Such  cases suggest that the check for NULL is either redundant, or that it needs\nto be moved to before the pointer is dereferenced.\n\nThis diagnostic  also  considers  values  passed  to  a  function  argument  marked  with\n\"attribute((nonnull))\"  as requiring a non-NULL value, and thus will complain if such\nvalues are checked for \"NULL\" after returning from such a function call.\n\nThis diagnostic is unlikely to be reported when any level of optimization is enabled,  as\nGCC's optimization logic will typically consider such checks for NULL as being redundant,\nand  optimize  them  away  before the analyzer \"sees\" them.  Hence optimization should be\ndisabled when attempting to trigger this diagnostic.\n"
                },
                {
                    "name": "-Wno-analyzer-double-fclose",
                    "content": "This warning requires -fanalyzer, which enables it;  use  -Wno-analyzer-double-fclose  to\ndisable it.\n\nThis  diagnostic  warns  for paths through the code in which a \"FILE *\" can have \"fclose\"\ncalled on it more than once.\n\nSee     CWE-1341:    Multiple     Releases     of     Same     Resource     or     Handle\n(\"https://cwe.mitre.org/data/definitions/1341.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-double-free",
                    "content": "This  warning  requires  -fanalyzer,  which  enables it; use -Wno-analyzer-double-free to\ndisable it.\n\nThis diagnostic warns for  paths  through  the  code  in  which  a  pointer  can  have  a\ndeallocator  called  on  it more than once, either \"free\", or a deallocator referenced by\nattribute \"malloc\".\n\nSee  CWE-415: Double Free (\"https://cwe.mitre.org/data/definitions/415.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-exposure-through-output-file",
                    "content": "This     warning      requires      -fanalyzer,      which      enables      it;      use\n-Wno-analyzer-exposure-through-output-file to disable it.\n\nThis  diagnostic  warns for paths through the code in which a security-sensitive value is\nwritten to an output file (such as writing a password to a log file).\n\nSee        CWE-532:       Information       Exposure       Through       Log        Files\n(\"https://cwe.mitre.org/data/definitions/532.html\").\n"
                },
                {
                    "name": "-Wanalyzer-exposure-through-uninit-copy",
                    "content": "This  warning requires both -fanalyzer and the use of a plugin to specify a function that\ncopies across a  \"trust  boundary\".   Use  -Wno-analyzer-exposure-through-uninit-copy  to\ndisable it.\n\nThis  diagnostic  warns  for  \"infoleaks\" - paths through the code in which uninitialized\nvalues are copied across a security boundary (such as  code  within  an  OS  kernel  that\ncopies a partially-initialized struct on the stack to user space).\n\nSee    CWE-200:   Exposure   of   Sensitive   Information   to   an   Unauthorized  Actor\n(\"https://cwe.mitre.org/data/definitions/200.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-fd-access-mode-mismatch",
                    "content": "This     warning      requires      -fanalyzer,      which      enables      it;      use\n-Wno-analyzer-fd-access-mode-mismatch to disable it.\n\nThis  diagnostic  warns  for  paths  through  code in which a \"read\" on a write-only file\ndescriptor is attempted, or vice versa.\n\nThis diagnostic also  warns  for  code  paths  in  a  which  a  function  with  attribute\n\"fdargread  (N)\"  is called with a file descriptor opened with \"OWRONLY\" at referenced\nargument \"N\" or a function with attribute  \"fdargwrite  (N)\"  is  called  with  a  file\ndescriptor opened with \"ORDONLY\" at referenced argument N.\n"
                },
                {
                    "name": "-Wno-analyzer-fd-double-close",
                    "content": "This  warning requires -fanalyzer, which enables it; use -Wno-analyzer-fd-double-close to\ndisable it.\n\nThis diagnostic warns for paths through code in which a file  descriptor  can  be  closed\nmore than once.\n\nSee      CWE-1341:     Multiple     Releases     of     Same     Resource    or    Handle\n(\"https://cwe.mitre.org/data/definitions/1341.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-fd-leak",
                    "content": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-fd-leak to  disable\nit.\n\nThis diagnostic warns for paths through code in which an open file descriptor is leaked.\n\nSee   CWE-775:  Missing  Release  of  File  Descriptor or Handle after Effective Lifetime\n(\"https://cwe.mitre.org/data/definitions/775.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-fd-phase-mismatch",
                    "content": "This warning requires -fanalyzer, which enables it;  use  -Wno-analyzer-fd-phase-mismatch\nto disable it.\n\nThis  diagnostic  warns  for paths through code in which an operation is attempted in the\nwrong phase of a file descriptor's lifetime.  For example, it will warn  on  attempts  to\ncall \"accept\" on a stream socket that has not yet had \"listen\" successfully called on it.\n\nSee     CWE-666:    Operation    on    Resource    in    Wrong    Phase    of    Lifetime\n(\"https://cwe.mitre.org/data/definitions/666.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-fd-type-mismatch",
                    "content": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-fd-type-mismatch to\ndisable it.\n\nThis diagnostic warns for paths through code in which an operation is  attempted  on  the\nwrong  type  of  file  descriptor.   For  example, it will warn on attempts to use socket\noperations on a file descriptor obtained via \"open\", or when attempting to use  a  stream\nsocket operation on a datagram socket.\n"
                },
                {
                    "name": "-Wno-analyzer-fd-use-after-close",
                    "content": "This  warning requires -fanalyzer, which enables it; use -Wno-analyzer-fd-use-after-close\nto disable it.\n\nThis diagnostic warns for paths through code in which a read or  write  is  called  on  a\nclosed file descriptor.\n\nThis  diagnostic  also  warns  for  paths through code in which a function with attribute\n\"fdarg (N)\" or \"fdargread (N)\" or \"fdargwrite (N)\" is  called  with  a  closed  file\ndescriptor at referenced argument \"N\".\n"
                },
                {
                    "name": "-Wno-analyzer-fd-use-without-check",
                    "content": "This      warning      requires      -fanalyzer,      which      enables      it;     use\n-Wno-analyzer-fd-use-without-check to disable it.\n\nThis diagnostic warns for paths through code in which a file descriptor is  used  without\nbeing checked for validity.\n\nThis  diagnostic  also  warns  for  paths through code in which a function with attribute\n\"fdarg (N)\" or \"fdargread (N)\" or \"fdargwrite (N)\" is called with a file descriptor,\nat referenced argument \"N\", without being checked for validity.\n"
                },
                {
                    "name": "-Wno-analyzer-file-leak",
                    "content": "This warning requires  -fanalyzer,  which  enables  it;  use  -Wno-analyzer-file-leak  to\ndisable it.\n\nThis  diagnostic  warns for paths through the code in which a \"<stdio.h>\" \"FILE *\" stream\nobject is leaked.\n\nSee  CWE-775: Missing Release of File  Descriptor  or  Handle  after  Effective  Lifetime\n(\"https://cwe.mitre.org/data/definitions/775.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-free-of-non-heap",
                    "content": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-free-of-non-heap to\ndisable it.\n\nThis  diagnostic warns for paths through the code in which \"free\" is called on a non-heap\npointer (e.g. an on-stack buffer, or a global).\n\nSee       CWE-590:      Free      of       Memory       not       on       the       Heap\n(\"https://cwe.mitre.org/data/definitions/590.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-imprecise-fp-arithmetic",
                    "content": "This      warning      requires      -fanalyzer,      which      enables      it;     use\n-Wno-analyzer-imprecise-fp-arithmetic to disable it.\n\nThis diagnostic warns for paths through the code in which  floating-point  arithmetic  is\nused in locations where precise computation is needed.  This diagnostic only warns on use\nof floating-point operands inside the calculation of an allocation size at the moment.\n"
                },
                {
                    "name": "-Wno-analyzer-infinite-recursion",
                    "content": "This  warning requires -fanalyzer, which enables it; use -Wno-analyzer-infinite-recursion\nto disable it.\n\nThis diagnostics warns for paths through the  code  which  appear  to  lead  to  infinite\nrecursion.\n\nSpecifically,  when  the  analyzer  \"sees\" a recursive call, it will compare the state of\nmemory at the entry to the new frame with that at the entry to the previous frame of that\nfunction on the stack.  The warning  is  issued  if  nothing  in  memory  appears  to  be\nchanging;  any  changes  observed  to  parameters  or  globals  are  assumed  to  lead to\ntermination of the recursion and thus suppress the warning.\n\nThis diagnostic is likely to miss cases  of  infinite  recursion  that  are  convered  to\niteration by the optimizer before the analyzer \"sees\" them.  Hence optimization should be\ndisabled when attempting to trigger this diagnostic.\n\nCompare   with   -Winfinite-recursion,  which  provides  a  similar  diagnostic,  but  is\nimplemented in a different way.\n"
                },
                {
                    "name": "-Wno-analyzer-jump-through-null",
                    "content": "This warning requires -fanalyzer, which enables it;  use  -Wno-analyzer-jump-through-null\nto disable it.\n\nThis  diagnostic  warns  for paths through the code in which a \"NULL\" function pointer is\ncalled.\n"
                },
                {
                    "name": "-Wno-analyzer-malloc-leak",
                    "content": "This warning requires -fanalyzer, which  enables  it;  use  -Wno-analyzer-malloc-leak  to\ndisable it.\n\nThis  diagnostic  warns  for  paths  through the code in which a pointer allocated via an\nallocator is leaked: either \"malloc\", or a function marked with attribute \"malloc\".\n\nSee     CWE-401:    Missing    Release    of    Memory    after    Effective     Lifetime\n(\"https://cwe.mitre.org/data/definitions/401.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-mismatching-deallocation",
                    "content": "This      warning      requires      -fanalyzer,      which      enables      it;     use\n-Wno-analyzer-mismatching-deallocation to disable it.\n\nThis diagnostic warns for paths through the code in which the wrong deallocation function\nis called on a pointer value, based on which function was used to  allocate  the  pointer\nvalue.   The  diagnostic  will  warn about mismatches between \"free\", scalar \"delete\" and\nvector \"delete[]\", and  those  marked  as  allocator/deallocator  pairs  using  attribute\n\"malloc\".\n\nSee          CWE-762:         Mismatched         Memory        Management        Routines\n(\"https://cwe.mitre.org/data/definitions/762.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-out-of-bounds",
                    "content": "This warning requires -fanalyzer, which enables it;  use  -Wno-analyzer-out-of-bounds  to\ndisable it.\n\nThis  diagnostic warns for paths through the code in which a buffer is definitely read or\nwritten out-of-bounds.  The diagnostic applies for cases where the analyzer  is  able  to\ndetermine  a  constant  offset and for accesses past the end of a buffer, also a constant\ncapacity.  Further, the diagnostic does limited checking for accesses past the  end  when\nthe offset as well as the capacity is symbolic.\n\nSee   CWE-119:  Improper  Restriction  of Operations within the Bounds of a Memory Buffer\n(\"https://cwe.mitre.org/data/definitions/119.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-possible-null-argument",
                    "content": "This     warning      requires      -fanalyzer,      which      enables      it;      use\n-Wno-analyzer-possible-null-argument to disable it.\n\nThis diagnostic warns for paths through the code in which a possibly-NULL value is passed\nto  a  function  argument  marked with \"attribute((nonnull))\" as requiring a non-NULL\nvalue.\n\nSee     CWE-690:    Unchecked    Return    Value    to    NULL    Pointer     Dereference\n(\"https://cwe.mitre.org/data/definitions/690.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-possible-null-dereference",
                    "content": "This      warning      requires      -fanalyzer,      which      enables      it;     use\n-Wno-analyzer-possible-null-dereference to disable it.\n\nThis diagnostic warns for paths through the  code  in  which  a  possibly-NULL  value  is\ndereferenced.\n\nSee      CWE-690:    Unchecked    Return    Value    to    NULL    Pointer    Dereference\n(\"https://cwe.mitre.org/data/definitions/690.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-null-argument",
                    "content": "This warning requires -fanalyzer, which enables it;  use  -Wno-analyzer-null-argument  to\ndisable it.\n\nThis  diagnostic  warns  for  paths through the code in which a value known to be NULL is\npassed to a function argument marked with \"attribute((nonnull))\" as requiring a  non-\nNULL value.\n\nSee               CWE-476:              NULL              Pointer             Dereference\n(\"https://cwe.mitre.org/data/definitions/476.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-null-dereference",
                    "content": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-null-dereference to\ndisable it.\n\nThis diagnostic warns for paths through the code in which a value known  to  be  NULL  is\ndereferenced.\n\nSee               CWE-476:              NULL              Pointer             Dereference\n(\"https://cwe.mitre.org/data/definitions/476.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-putenv-of-auto-var",
                    "content": "This warning requires -fanalyzer, which enables it; use  -Wno-analyzer-putenv-of-auto-var\nto disable it.\n\nThis  diagnostic warns for paths through the code in which a call to \"putenv\" is passed a\npointer to an automatic variable or an on-stack buffer.\n\nSee  POS34-C. Do not call putenv() with  a  pointer  to  an  automatic  variable  as  the\nargument (\"https://wiki.sei.cmu.edu/confluence/x/6NYxBQ\").\n"
                },
                {
                    "name": "-Wno-analyzer-shift-count-negative",
                    "content": "This      warning      requires      -fanalyzer,      which      enables      it;     use\n-Wno-analyzer-shift-count-negative to disable it.\n\nThis diagnostic warns for paths through the code in which a shift  is  attempted  with  a\nnegative  count.  It is analogous to the -Wshift-count-negative diagnostic implemented in\nthe C/C++ front ends, but is implemented based on analyzing interprocedural paths, rather\nthan merely parsing the syntax tree.  However, the analyzer does not prioritize detection\nof such paths, so false negatives are more likely relative to other warnings.\n"
                },
                {
                    "name": "-Wno-analyzer-shift-count-overflow",
                    "content": "This     warning      requires      -fanalyzer,      which      enables      it;      use\n-Wno-analyzer-shift-count-overflow to disable it.\n\nThis  diagnostic  warns  for  paths through the code in which a shift is attempted with a\ncount greater than or equal to the precision of the operand's type.  It is  analogous  to\nthe  -Wshift-count-overflow  diagnostic  implemented  in  the  C/C++  front  ends, but is\nimplemented based on analyzing interprocedural paths,  rather  than  merely  parsing  the\nsyntax tree.  However, the analyzer does not prioritize detection of such paths, so false\nnegatives are more likely relative to other warnings.\n"
                },
                {
                    "name": "-Wno-analyzer-stale-setjmp-buffer",
                    "content": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-stale-setjmp-buffer\nto disable it.\n\nThis  diagnostic  warns for paths through the code in which \"longjmp\" is called to rewind\nto a \"jmpbuf\" relating to a \"setjmp\" call in a function that has returned.\n\nWhen \"setjmp\" is called on a \"jmpbuf\" to record a rewind location, it records the  stack\nframe.   The  stack  frame becomes invalid when the function containing the \"setjmp\" call\nreturns.  Attempting to rewind to it via \"longjmp\" would reference a stack frame that  no\nlonger exists, and likely lead to a crash (or worse).\n"
                },
                {
                    "name": "-Wno-analyzer-tainted-allocation-size",
                    "content": "This  warning  requires  both  -fanalyzer  and -fanalyzer-checker=taint to enable it; use\n-Wno-analyzer-tainted-allocation-size to disable it.\n\nThis diagnostic warns for paths through the code in which a value that could be under  an\nattacker's  control is used as the size of an allocation without being sanitized, so that\nan attacker could inject an excessively large allocation and potentially cause  a  denial\nof service attack.\n\nSee       CWE-789:      Memory      Allocation      with     Excessive     Size     Value\n(\"https://cwe.mitre.org/data/definitions/789.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-tainted-assertion",
                    "content": "This warning requires both -fanalyzer and  -fanalyzer-checker=taint  to  enable  it;  use\n-Wno-analyzer-tainted-assertion to disable it.\n\nThis  diagnostic warns for paths through the code in which a value that could be under an\nattacker's control is used as part of a condition without being first sanitized, and that\ncondition guards a call to a function marked  with  attribute  \"noreturn\"  (such  as  the\nfunction   \"builtinunreachable\").    Such   functions   typically   indicate  abnormal\ntermination of the program, such as for assertion failure handlers.  For example:\n\nassert (sometaintedvalue < SOMELIMIT);\n\nIn such cases:\n\n*   when assertion-checking is enabled: an attacker could trigger a denial of service  by\ninjecting an assertion failure\n\n*   when  assertion-checking is disabled, such as by defining \"NDEBUG\", an attacker could\ninject data that subverts the process, since it presumably  violates  a  precondition\nthat is being assumed by the code.\n\nNote  that  when  assertion-checking is disabled, the assertions are typically removed by\nthe preprocessor before the analyzer has a chance to \"see\" them, so this  diagnostic  can\nonly generate warnings on builds in which assertion-checking is enabled.\n\nFor  the  purpose  of  this  warning,  any  function  marked with attribute \"noreturn\" is\nconsidered as a possible assertion failure  handler,  including  \"builtinunreachable\".\nNote  that  these  functions  are  sometimes removed by the optimizer before the analyzer\n\"sees\" them.  Hence optimization should be  disabled  when  attempting  to  trigger  this\ndiagnostic.\n\nSee  CWE-617: Reachable Assertion (\"https://cwe.mitre.org/data/definitions/617.html\").\n\nThe warning can also report problematic constructions such as\n\nswitch (sometaintedvalue) {\ncase 0:\n/* [...etc; various valid cases omitted...] */\nbreak;\n\ndefault:\nbuiltinunreachable (); /* BUG: attacker can trigger this  */\n}\n\ndespite the above not being an assertion failure, strictly speaking.\n"
                },
                {
                    "name": "-Wno-analyzer-tainted-array-index",
                    "content": "This  warning  requires  both  -fanalyzer  and -fanalyzer-checker=taint to enable it; use\n-Wno-analyzer-tainted-array-index to disable it.\n\nThis diagnostic warns for paths through the code in which a value that could be under  an\nattacker's  control  is  used as the index of an array access without being sanitized, so\nthat an attacker could inject an out-of-bounds access.\n\nSee        CWE-129:        Improper        Validation        of        Array        Index\n(\"https://cwe.mitre.org/data/definitions/129.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-tainted-divisor",
                    "content": "This  warning  requires  both  -fanalyzer  and -fanalyzer-checker=taint to enable it; use\n-Wno-analyzer-tainted-divisor to disable it.\n\nThis diagnostic warns for paths through the code in which a value that could be under  an\nattacker's  control  is  used  as  the divisor in a division or modulus operation without\nbeing sanitized, so that an attacker could inject a division-by-zero.\n\nSee  CWE-369: Divide By Zero (\"https://cwe.mitre.org/data/definitions/369.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-tainted-offset",
                    "content": "This warning requires both -fanalyzer and  -fanalyzer-checker=taint  to  enable  it;  use\n-Wno-analyzer-tainted-offset to disable it.\n\nThis  diagnostic warns for paths through the code in which a value that could be under an\nattacker's control is used as a pointer  offset  without  being  sanitized,  so  that  an\nattacker could inject an out-of-bounds access.\n\nSee         CWE-823:        Use        of        Out-of-range        Pointer       Offset\n(\"https://cwe.mitre.org/data/definitions/823.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-tainted-size",
                    "content": "This warning requires both -fanalyzer and  -fanalyzer-checker=taint  to  enable  it;  use\n-Wno-analyzer-tainted-size to disable it.\n\nThis  diagnostic warns for paths through the code in which a value that could be under an\nattacker's control is used as the size of an operation such  as  \"memset\"  without  being\nsanitized, so that an attacker could inject an out-of-bounds access.\n\nSee         CWE-129:        Improper        Validation        of        Array       Index\n(\"https://cwe.mitre.org/data/definitions/129.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-unsafe-call-within-signal-handler",
                    "content": "This     warning      requires      -fanalyzer,      which      enables      it;      use\n-Wno-analyzer-unsafe-call-within-signal-handler to disable it.\n\nThis  diagnostic  warns for paths through the code in which a function known to be async-\nsignal-unsafe (such as \"fprintf\") is called from a signal handler.\n\nSee     CWE-479:    Signal    Handler     Use     of     a     Non-reentrant     Function\n(\"https://cwe.mitre.org/data/definitions/479.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-use-after-free",
                    "content": "This  warning  requires -fanalyzer, which enables it; use -Wno-analyzer-use-after-free to\ndisable it.\n\nThis diagnostic warns for paths through the code in which  a  pointer  is  used  after  a\ndeallocator  is  called  on  it:  either \"free\", or a deallocator referenced by attribute\n\"malloc\".\n\nSee  CWE-416: Use After Free (\"https://cwe.mitre.org/data/definitions/416.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-use-of-pointer-in-stale-stack-frame",
                    "content": "This     warning      requires      -fanalyzer,      which      enables      it;      use\n-Wno-analyzer-use-of-pointer-in-stale-stack-frame to disable it.\n\nThis  diagnostic warns for paths through the code in which a pointer is dereferenced that\npoints to a variable in a stale stack frame.\n"
                },
                {
                    "name": "-Wno-analyzer-va-arg-type-mismatch",
                    "content": "This     warning      requires      -fanalyzer,      which      enables      it;      use\n-Wno-analyzer-va-arg-type-mismatch to disable it.\n\nThis  diagnostic  warns for interprocedural paths through the code for which the analyzer\ndetects an attempt to use \"vaarg\" to extract a value passed to a variadic call, but uses\na type that does not match that of the expression passed to the call.\n\nSee      CWE-686:     Function      Call      With      Incorrect      Argument      Type\n(\"https://cwe.mitre.org/data/definitions/686.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-va-list-exhausted",
                    "content": "This  warning  requires -fanalyzer, which enables it; use -Wno-analyzer-va-list-exhausted\nto disable it.\n\nThis diagnostic warns for interprocedural paths through the code for which  the  analyzer\ndetects  an  attempt  to use \"vaarg\" to access the next value passed to a variadic call,\nbut all of the values in the \"valist\" have already been consumed.\n\nSee     CWE-685:    Function    Call    With    Incorrect     Number     of     Arguments\n(\"https://cwe.mitre.org/data/definitions/685.html\").\n"
                },
                {
                    "name": "-Wno-analyzer-va-list-leak",
                    "content": "This  warning  requires  -fanalyzer,  which enables it; use -Wno-analyzer-va-list-leak to\ndisable it.\n\nThis diagnostic warns for interprocedural paths through the code for which  the  analyzer\ndetects  that  \"vastart\"  or  \"vacopy\"  has  been  called  on  a  \"valist\"  without  a\ncorresponding call to \"vaend\".\n"
                },
                {
                    "name": "-Wno-analyzer-va-list-use-after-va-end",
                    "content": "This     warning      requires      -fanalyzer,      which      enables      it;      use\n-Wno-analyzer-va-list-use-after-va-end to disable it.\n\nThis  diagnostic  warns for interprocedural paths through the code for which the analyzer\ndetects an attempt to use a \"valist\"  after \"vaend\" has been called on it.  \"valist\".\n"
                },
                {
                    "name": "-Wno-analyzer-write-to-const",
                    "content": "This warning requires -fanalyzer, which enables it; use  -Wno-analyzer-write-to-const  to\ndisable it.\n\nThis diagnostic warns for paths through the code in which the analyzer detects an attempt\nto  write  through  a  pointer  to  a  \"const\"  object.   However,  the analyzer does not\nprioritize detection of such paths, so false negatives are more likely relative to  other\nwarnings.\n"
                },
                {
                    "name": "-Wno-analyzer-write-to-string-literal",
                    "content": "This      warning      requires      -fanalyzer,      which      enables      it;     use\n-Wno-analyzer-write-to-string-literal to disable it.\n\nThis diagnostic warns for paths through the code in which the analyzer detects an attempt\nto write through a  pointer  to  a  string  literal.   However,  the  analyzer  does  not\nprioritize  detection of such paths, so false negatives are more likely relative to other\nwarnings.\n"
                },
                {
                    "name": "-Wno-analyzer-use-of-uninitialized-value",
                    "content": "This     warning      requires      -fanalyzer,      which      enables      it;      use\n-Wno-analyzer-use-of-uninitialized-value to disable it.\n\nThis diagnostic warns for paths through the code in which an uninitialized value is used.\n\nSee            CWE-457:          Use          of          Uninitialized          Variable\n(\"https://cwe.mitre.org/data/definitions/457.html\").\n\nThe analyzer has hardcoded knowledge about the behavior of  the  following  memory-management\nfunctions:\n\n*<\"alloca\">\n*<The built-in functions \"builtinalloc\",>\n\"builtinallocwithalign\",       @item      \"builtincalloc\",      \"builtinfree\",\n\"builtinmalloc\",   \"builtinmemcpy\",   \"builtinmemcpychk\",   \"builtinmemset\",\n\"builtinmemsetchk\",      \"builtinrealloc\",      \"builtinstackrestore\",     and\n\"builtinstacksave\"\n\n*<\"calloc\">\n*<\"free\">\n*<\"malloc\">\n*<\"memset\">\n*<\"operator delete\">\n*<\"operator delete []\">\n*<\"operator new\">\n*<\"operator new []\">\n*<\"realloc\">\n*<\"strdup\">\n*<\"strndup\">\n\nof the following functions for working with file descriptors:\n\n*<\"open\">\n*<\"close\">\n*<\"creat\">\n*<\"dup\", \"dup2\" and \"dup3\">\n*<\"isatty\">\n*<\"pipe\", and \"pipe2\">\n*<\"read\">\n*<\"write\">\n*<\"socket\", \"bind\", \"listen\", \"accept\", and \"connect\">\n\nof the following functions for working with \"<stdio.h>\" streams:\n\n*<The built-in functions \"builtinfprintf\",>\n\"builtinfprintfunlocked\",       \"builtinfputc\",        \"builtinfputcunlocked\",\n\"builtinfputs\",             \"builtinfputsunlocked\",            \"builtinfwrite\",\n\"builtinfwriteunlocked\",       \"builtinprintf\",       \"builtinprintfunlocked\",\n\"builtinputc\",            \"builtinputchar\",           \"builtinputcharunlocked\",\n\"builtinputcunlocked\",          \"builtinputs\",          \"builtinputsunlocked\",\n\"builtinvfprintf\", and \"builtinvprintf\"\n\n*<\"fopen\">\n*<\"fclose\">\n*<\"ferror\">\n*<\"fgets\">\n*<\"fgetsunlocked\">\n*<\"fileno\">\n*<\"fread\">\n*<\"getc\">\n*<\"getchar\">\n*<\"fprintf\">\n*<\"printf\">\n*<\"fwrite\">\n\nand of the following functions:\n\n*<The built-in functions \"builtinexpect\",>\n\"builtinexpectwithprobability\",        \"builtinstrchr\",       \"builtinstrcpy\",\n\"builtinstrcpychk\", \"builtinstrlen\", \"builtinvacopy\", and \"builtinvastart\"\n\n*<The GNU extensions \"error\" and \"erroratline\">\n*<\"getpass\">\n*<\"longjmp\">\n*<\"putenv\">\n*<\"setjmp\">\n*<\"siglongjmp\">\n*<\"signal\">\n*<\"sigsetjmp\">\n*<\"strchr\">\n*<\"strlen\">\n\nIn addition, various functions with an \"analyzer\"  prefix  have  special  meaning  to  the\nanalyzer, described in the GCC Internals manual.\n\nPertinent parameters for controlling the exploration are:\n\n*<--param analyzer-bb-explosion-factor=value>\n*<--param analyzer-max-enodes-per-program-point=value>\n*<--param analyzer-max-recursion-depth=value>\n*<--param analyzer-min-snodes-for-call-summary=value>\n\nThe following options control the analyzer.\n"
                },
                {
                    "name": "-fanalyzer-call-summaries",
                    "content": "Simplify  interprocedural  analysis by computing the effect of certain calls, rather than\nexploring all paths through the function from callsite to each possible return.\n\nIf enabled, call summaries are only used for functions with more than one call site,  and\nthat        are        sufficiently        complicated        (as       per       --param\nanalyzer-min-snodes-for-call-summary=value).\n"
                },
                {
                    "name": "-fanalyzer-checker=_",
                    "content": "Restrict the analyzer to run just the named checker, and enable it.\n\nSome checkers are disabled by default (even with -fanalyzer), such as the \"taint\" checker\nthat implements -Wanalyzer-tainted-array-index, and this option  is  required  to  enable\nthem.\n\nNote:   currently,   -fanalyzer-checker=taint   disables   the  following  warnings  from\n-fanalyzer:\n\n-Wanalyzer-deref-before-check       -Wanalyzer-double-fclose       -Wanalyzer-double-free\n-Wanalyzer-exposure-through-output-file                -Wanalyzer-fd-access-mode-mismatch\n-Wanalyzer-fd-double-close        -Wanalyzer-fd-leak        -Wanalyzer-fd-use-after-close\n-Wanalyzer-fd-use-without-check      -Wanalyzer-file-leak     -Wanalyzer-free-of-non-heap\n-Wanalyzer-malloc-leak    -Wanalyzer-mismatching-deallocation    -Wanalyzer-null-argument\n-Wanalyzer-null-dereference                             -Wanalyzer-possible-null-argument\n-Wanalyzer-possible-null-dereference         -Wanalyzer-unsafe-call-within-signal-handler\n-Wanalyzer-use-after-free -Wanalyzer-va-list-leak -Wanalyzer-va-list-use-after-va-end\n"
                },
                {
                    "name": "-fno-analyzer-feasibility",
                    "content": "This option is intended for analyzer developers.\n\nBy  default  the  analyzer  verifies  that there is a feasible control flow path for each\ndiagnostic  it  emits:  that  the  conditions  that  hold  are  not  mutually  exclusive.\nDiagnostics  for which no feasible path can be found are rejected.  This filtering can be\nsuppressed with -fno-analyzer-feasibility, for debugging issues in this code.\n"
                },
                {
                    "name": "-fanalyzer-fine-grained",
                    "content": "This option is intended for analyzer developers.\n\nInternally the analyzer builds an \"exploded graph\" that combines control flow graphs with\ndata flow information.\n\nBy default, an edge in this graph can contain the effects of a run of multiple statements\nwithin a basic block.  With -fanalyzer-fine-grained, each statement gets its own edge.\n"
                },
                {
                    "name": "-fanalyzer-show-duplicate-count",
                    "content": "This option is intended for  analyzer  developers:  if  multiple  diagnostics  have  been\ndetected  as  being  duplicates  of  each  other, it emits a note when reporting the best\ndiagnostic, giving the number of additional  diagnostics  that  were  suppressed  by  the\ndeduplication logic.\n"
                },
                {
                    "name": "-fno-analyzer-state-merge",
                    "content": "This option is intended for analyzer developers.\n\nBy  default  the  analyzer  attempts to simplify analysis by merging sufficiently similar\nstates  at  each   program   point   as   it   builds   its   \"exploded   graph\".    With\n-fno-analyzer-state-merge  this  merging  can be suppressed, for debugging state-handling\nissues.\n"
                },
                {
                    "name": "-fno-analyzer-state-purge",
                    "content": "This option is intended for analyzer developers.\n\nBy default the analyzer attempts to simplify analysis by purging aspects of  state  at  a\nprogram  point that appear to no longer be relevant e.g. the values of locals that aren't\naccessed later in the function and which aren't relevant to leak analysis.\n\nWith -fno-analyzer-state-purge this purging of state can  be  suppressed,  for  debugging\nstate-handling issues.\n"
                },
                {
                    "name": "-fno-analyzer-suppress-followups",
                    "content": "This option is intended for analyzer developers.\n\nBy  default the analyzer will stop exploring an execution path after encountering certain\ndiagnostics, in order to avoid potentially issuing a cascade of follow-up diagnostics.\n\nThe diagnostics that terminate analysis along a path are:\n\n*<-Wanalyzer-null-argument>\n*<-Wanalyzer-null-dereference>\n*<-Wanalyzer-use-after-free>\n*<-Wanalyzer-use-of-pointer-in-stale-stack-frame>\n*<-Wanalyzer-use-of-uninitialized-value>\n\nWith -fno-analyzer-suppress-followups the analyzer will continue to  explore  such  paths\neven  after  such diagnostics, which may be helpful for debugging issues in the analyzer,\nor for microbenchmarks for detecting undefined behavior.\n"
                },
                {
                    "name": "-fanalyzer-transitivity",
                    "content": "This option enables transitivity of constraints within the analyzer.\n"
                },
                {
                    "name": "-fno-analyzer-undo-inlining",
                    "content": "This option is intended for analyzer developers.\n\n-fanalyzer runs  relatively  late  compared  to  other  code  analysis  tools,  and  some\noptimizations have already been applied to the code.  In particular function inlining may\nhave  occurred,  leading  to  the interprocedural execution paths emitted by the analyzer\ncontaining function frames that don't correspond to those in the original source code.\n\nBy default the analyzer attempts to reconstruct the original function frames, and to emit\nevents showing the inlined calls.\n\nWith  -fno-analyzer-undo-inlining  this  attempt  to  reconstruct  the   original   frame\ninformation  can  be  be  disabled,  which  may  be  of help when debugging issues in the\nanalyzer.\n"
                },
                {
                    "name": "-fanalyzer-verbose-edges",
                    "content": "This option is intended for analyzer developers.  It enables  more  verbose,  lower-level\ndetail in the descriptions of control flow within diagnostic paths.\n"
                },
                {
                    "name": "-fanalyzer-verbose-state-changes",
                    "content": "This  option  is  intended for analyzer developers.  It enables more verbose, lower-level\ndetail in the descriptions of events relating to state machines within diagnostic paths.\n"
                },
                {
                    "name": "-fanalyzer-verbosity=_",
                    "content": "This option controls the complexity of the  control  flow  paths  that  are  emitted  for\nanalyzer diagnostics.\n\nThe level can be one of:\n\n0   At  this  level, interprocedural call and return events are displayed, along with the\nmost pertinent state-change events relating to a  diagnostic.   For  example,  for  a\ndouble-\"free\" diagnostic, both calls to \"free\" will be shown.\n\n1   As per the previous level, but also show events for the entry to each function.\n\n2   As  per  the  previous  level, but also show events relating to control flow that are\nsignificant to triggering the issue (e.g. \"true path taken\" at a conditional).\n\nThis level is the default.\n\n3   As per the previous level, but show all control flow  events,  not  just  significant\nones.\n\n4   This level is intended for analyzer developers; it adds various other events intended\nfor debugging the analyzer.\n"
                },
                {
                    "name": "-fdump-analyzer",
                    "content": "Dump   internal   details   about  what  the  analyzer  is  doing  to  file.analyzer.txt.\n-fdump-analyzer-stderr overrides this option.\n"
                },
                {
                    "name": "-fdump-analyzer-stderr",
                    "content": "Dump internal details about what the analyzer is doing to stderr.  This option  overrides\n-fdump-analyzer.\n"
                },
                {
                    "name": "-fdump-analyzer-callgraph",
                    "content": "Dump  a  representation  of  the  call  graph  suitable  for  viewing  with  GraphViz  to\nfile.callgraph.dot.\n"
                },
                {
                    "name": "-fdump-analyzer-exploded-graph",
                    "content": "Dump a representation of the \"exploded graph\"  suitable  for  viewing  with  GraphViz  to\nfile.eg.dot.   Nodes  are  color-coded  based  on state-machine states to emphasize state\nchanges.\n"
                },
                {
                    "name": "-fdump-analyzer-exploded-nodes",
                    "content": "Emit diagnostics showing where nodes in the \"exploded  graph\"  are  in  relation  to  the\nprogram source.\n"
                },
                {
                    "name": "-fdump-analyzer-exploded-nodes-2",
                    "content": "Dump a textual representation of the \"exploded graph\" to file.eg.txt.\n"
                },
                {
                    "name": "-fdump-analyzer-exploded-nodes-3",
                    "content": "Dump  a  textual  representation  of  the  \"exploded graph\" to one dump file per node, to\nfile.eg-id.txt.  This is typically a large number of dump files.\n"
                },
                {
                    "name": "-fdump-analyzer-exploded-paths",
                    "content": "Dump  a  textual  representation  of  the  \"exploded  path\"  for   each   diagnostic   to\nfile.idx.kind.epath.txt.\n"
                },
                {
                    "name": "-fdump-analyzer-feasibility",
                    "content": "Dump  internal  details  about the analyzer's search for feasible paths.  The details are\nwritten in  a  form  suitable  for  viewing  with  GraphViz  to  filenames  of  the  form\nfile.*.fg.dot, file.*.tg.dot, and file.*.fpath.txt.\n"
                },
                {
                    "name": "-fdump-analyzer-json",
                    "content": "Dump  a  compressed  JSON  representation of analyzer internals to file.analyzer.json.gz.\nThe precise format is subject to change.\n"
                },
                {
                    "name": "-fdump-analyzer-state-purge",
                    "content": "As per -fdump-analyzer-supergraph, dump a representation of the \"supergraph\" suitable for\nviewing with GraphViz, but annotate the graph with information  on  what  state  will  be\npurged at each node.  The graph is written to file.state-purge.dot.\n"
                },
                {
                    "name": "-fdump-analyzer-supergraph",
                    "content": "Dump   representations  of  the  \"supergraph\"  suitable  for  viewing  with  GraphViz  to\nfile.supergraph.dot and to file.supergraph-eg.dot.  These show all of  the  control  flow\ngraphs in the program, with interprocedural edges for calls and returns.  The second dump\ncontains  annotations  showing  nodes  in the \"exploded graph\" and diagnostics associated\nwith them.\n"
                },
                {
                    "name": "-fdump-analyzer-untracked",
                    "content": "Emit custom warnings with internal details intended for analyzer developers.\n"
                },
                {
                    "name": "Options for Debugging Your Program",
                    "content": "To tell GCC to emit extra information for use by a debugger, in almost  all  cases  you  need\nonly  to add -g to your other options.  Some debug formats can co-exist (like DWARF with CTF)\nwhen each of them is enabled explicitly by adding the respective command line option to  your\nother options.\n\nGCC  allows you to use -g with -O.  The shortcuts taken by optimized code may occasionally be\nsurprising: some variables you declared may not exist at all; flow  of  control  may  briefly\nmove  where  you  did not expect it; some statements may not be executed because they compute\nconstant results or their values  are  already  at  hand;  some  statements  may  execute  in\ndifferent  places  because they have been moved out of loops.  Nevertheless it is possible to\ndebug optimized output.  This makes it reasonable to use  the  optimizer  for  programs  that\nmight have bugs.\n\nIf  you are not using some other optimization option, consider using -Og with -g.  With no -O\noption at all, some compiler passes that collect information useful for debugging do not  run\nat all, so that -Og may result in a better debugging experience.\n"
                },
                {
                    "name": "-g",
                    "content": "XCOFF, or DWARF).  GDB can work with this debugging information.\n\nOn most systems that use stabs format, -g enables use of extra debugging information that\nonly GDB can use; this extra information makes debugging work better in GDB but  probably\nmakes  other  debuggers  crash or refuse to read the program.  If you want to control for\ncertain whether to generate the extra information, use -gvms (see below).\n",
                    "flag": "-g"
                },
                {
                    "name": "-ggdb",
                    "content": "Produce debugging information for use by GDB.  This means  to  use  the  most  expressive\nformat  available (DWARF, stabs, or the native format if neither of those are supported),\nincluding GDB extensions if at all possible.\n"
                },
                {
                    "name": "-gdwarf",
                    "content": ""
                },
                {
                    "name": "-gdwarf-_",
                    "content": "Produce debugging information in DWARF format (if  that  is  supported).   The  value  of\nversion  may  be either 2, 3, 4 or 5; the default version for most targets is 5 (with the\nexception of VxWorks, TPF and Darwin/Mac OS X, which default to version 2, and AIX, which\ndefaults to version 4).\n\nNote that with DWARF Version 2, some ports require and always  use  some  non-conflicting\nDWARF 3 extensions in the unwind tables.\n\nVersion 4 may require GDB 7.0 and -fvar-tracking-assignments for maximum benefit. Version\n5 requires GDB 8.0 or higher.\n\nGCC  no  longer supports DWARF Version 1, which is substantially different than Version 2\nand  later.   For  historical  reasons,  some  other  DWARF-related   options   such   as\n-fno-dwarf2-cfi-asm)  retain  a reference to DWARF Version 2 in their names, but apply to\nall currently-supported versions of DWARF.\n"
                },
                {
                    "name": "-gbtf",
                    "content": "Request BTF debug information.  BTF is the default debugging format for the eBPF  target.\nOn other targets, like x86, BTF debug information can be generated along with DWARF debug\ninformation  when  both  of the debug formats are enabled explicitly via their respective\ncommand line options.\n"
                },
                {
                    "name": "-gctf",
                    "content": ""
                },
                {
                    "name": "-gctf_",
                    "content": "Request CTF debug information and use level to specify how  much  CTF  debug  information\nshould  be  produced.  If -gctf is specified without a value for level, the default level\nof CTF debug information is 2.\n\nCTF debug information can be generated along with DWARF debug information  when  both  of\nthe debug formats are enabled explicitly via their respective command line options.\n\nLevel 0 produces no CTF debug information at all.  Thus, -gctf0 negates -gctf.\n\nLevel   1   produces  CTF  information  for  tracebacks  only.   This  includes  callsite\ninformation, but does not include type information.\n\nLevel 2 produces type information for entities (functions, data objects etc.)   at  file-\nscope or global-scope only.\n"
                },
                {
                    "name": "-gvms",
                    "content": "Produce  debugging information in Alpha/VMS debug format (if that is supported).  This is\nthe format used by DEBUG on Alpha/VMS systems.\n"
                },
                {
                    "name": "-g_",
                    "content": ""
                },
                {
                    "name": "-ggdb_",
                    "content": ""
                },
                {
                    "name": "-gvms_",
                    "content": "Request debugging information and also use level to specify how  much  information.   The\ndefault level is 2.\n\nLevel 0 produces no debug information at all.  Thus, -g0 negates -g.\n\nLevel  1  produces  minimal  information,  enough  for  making backtraces in parts of the\nprogram that you don't plan to  debug.   This  includes  descriptions  of  functions  and\nexternal variables, and line number tables, but no information about local variables.\n\nLevel  3  includes  extra  information,  such as all the macro definitions present in the\nprogram.  Some debuggers support macro expansion when you use -g3.\n\nIf you use multiple -g options, with or without level numbers, the last  such  option  is\nthe one that is effective.\n\n-gdwarf   does   not   accept  a  concatenated  debug  level,  to  avoid  confusion  with\n-gdwarf-level.  Instead use an additional -glevel option to change the  debug  level  for\nDWARF.\n"
                },
                {
                    "name": "-fno-eliminate-unused-debug-symbols",
                    "content": "By  default, no debug information is produced for symbols that are not actually used. Use\nthis option if you want debug information for all symbols.\n"
                },
                {
                    "name": "-femit-class-debug-always",
                    "content": "Instead of emitting debugging information for a C++ class in only one object  file,  emit\nit  in  all object files using the class.  This option should be used only with debuggers\nthat are unable to handle the way GCC normally emits debugging  information  for  classes\nbecause  using  this  option  increases the size of debugging information by as much as a\nfactor of two.\n"
                },
                {
                    "name": "-fno-merge-debug-strings",
                    "content": "Direct the linker to not merge together strings in the  debugging  information  that  are\nidentical  in  different  object  files.   Merging  is not supported by all assemblers or\nlinkers.  Merging decreases the size of the debug information in the output file  at  the\ncost of increasing link processing time.  Merging is enabled by default.\n"
                },
                {
                    "name": "-fdebug-prefix-map=_",
                    "content": "When  compiling  files residing in directory old, record debugging information describing\nthem as if the files resided in directory new instead.  This can be  used  to  replace  a\nbuild-time  path  with  an  install-time  path in the debug info.  It can also be used to\nchange an absolute path to a relative path by using  .  for  new.   This  can  give  more\nreproducible  builds, which are location independent, but may require an extra command to\ntell  GDB  where  to  find   the   source   files.   See   also   -ffile-prefix-map   and\n-fcanon-prefix-map.\n"
                },
                {
                    "name": "-fvar-tracking",
                    "content": "Run  variable  tracking pass.  It computes where variables are stored at each position in\ncode.  Better debugging information is  then  generated  (if  the  debugging  information\nformat supports this information).\n\nIt  is enabled by default when compiling with optimization (-Os, -O, -O2, ...), debugging\ninformation (-g) and the debug info format supports it.\n"
                },
                {
                    "name": "-fvar-tracking-assignments",
                    "content": "Annotate assignments to user variables early in the compilation and attempt to carry  the\nannotations  over  throughout  the  compilation  all the way to the end, in an attempt to\nimprove debug information while optimizing.  Use of -gdwarf-4 is recommended  along  with\nit.\n\nIt can be enabled even if var-tracking is disabled, in which case annotations are created\nand maintained, but discarded at the end.  By default, this flag is enabled together with\n-fvar-tracking, except when selective scheduling is enabled.\n"
                },
                {
                    "name": "-gsplit-dwarf",
                    "content": "If  DWARF  debugging  information  is  enabled, separate as much debugging information as\npossible into a separate output file with the extension .dwo.   This  option  allows  the\nbuild  system  to  avoid linking files with debug information.  To be useful, this option\nrequires a debugger capable of reading .dwo files.\n"
                },
                {
                    "name": "-gdwarf32",
                    "content": ""
                },
                {
                    "name": "-gdwarf64",
                    "content": "If DWARF debugging information is enabled, the -gdwarf32 selects the 32-bit DWARF  format\nand  the  -gdwarf64  selects the 64-bit DWARF format.  The default is target specific, on\nmost targets it is -gdwarf32 though.  The 32-bit  DWARF  format  is  smaller,  but  can't\nsupport  more  than  2GiB  of  debug  information  in  any of the DWARF debug information\nsections.  The 64-bit DWARF format allows larger debug information and might not be  well\nsupported by all consumers yet.\n"
                },
                {
                    "name": "-gdescribe-dies",
                    "content": "Add  description  attributes  to  some  DWARF  DIEs  that have no name attribute, such as\nartificial variables, external references and call site parameter DIEs.\n"
                },
                {
                    "name": "-gpubnames",
                    "content": "Generate DWARF \".debugpubnames\" and \".debugpubtypes\" sections.\n"
                },
                {
                    "name": "-ggnu-pubnames",
                    "content": "Generate \".debugpubnames\" and  \".debugpubtypes\"  sections  in  a  format  suitable  for\nconversion  into  a GDB index.  This option is only useful with a linker that can produce\nGDB index version 7.\n"
                },
                {
                    "name": "-fdebug-types-section",
                    "content": "When using DWARF Version 4 or higher, type DIEs can be put into their own  \".debugtypes\"\nsection  instead  of making them part of the \".debuginfo\" section.  It is more efficient\nto put them in a separate comdat section since the linker  can  then  remove  duplicates.\nBut  not  all  DWARF  consumers  support  \".debugtypes\" sections yet and on some objects\n\".debugtypes\" produces larger instead of smaller debugging information.\n"
                },
                {
                    "name": "-grecord-gcc-switches",
                    "content": ""
                },
                {
                    "name": "-gno-record-gcc-switches",
                    "content": "This switch causes the command-line options used to invoke the compiler that  may  affect\ncode  generation  to  be  appended  to  the  DWATproducer  attribute in DWARF debugging\ninformation.  The options are concatenated with spaces separating them  from  each  other\nand from the compiler version.  It is enabled by default.  See also -frecord-gcc-switches\nfor another way of storing compiler options into the object file.\n"
                },
                {
                    "name": "-gstrict-dwarf",
                    "content": "Disallow   using   extensions   of  later  DWARF  standard  version  than  selected  with\n-gdwarf-version.  On most targets  using  non-conflicting  DWARF  extensions  from  later\nstandard versions is allowed.\n"
                },
                {
                    "name": "-gno-strict-dwarf",
                    "content": "Allow   using   extensions   of   later   DWARF   standard  version  than  selected  with\n-gdwarf-version.\n"
                },
                {
                    "name": "-gas-loc-support",
                    "content": "Inform the compiler that the assembler supports \".loc\" directives.  It may then use  them\nfor the assembler to generate DWARF2+ line number tables.\n\nThis  is  generally  desirable,  because assembler-generated line-number tables are a lot\nmore compact than those the compiler can generate itself.\n\nThis option will be enabled by default if, at GCC configure time, the assembler was found\nto support such directives.\n"
                },
                {
                    "name": "-gno-as-loc-support",
                    "content": "Force GCC to generate DWARF2+ line number  tables  internally,  if  DWARF2+  line  number\ntables are to be generated.\n"
                },
                {
                    "name": "-gas-locview-support",
                    "content": "Inform  the  compiler  that  the assembler supports \"view\" assignment and reset assertion\nchecking in \".loc\" directives.\n\nThis option will be enabled by default if, at GCC configure time, the assembler was found\nto support them.\n"
                },
                {
                    "name": "-gno-as-locview-support",
                    "content": "Force GCC to assign view numbers internally, if -gvariable-location-views are  explicitly\nrequested.\n"
                },
                {
                    "name": "-gcolumn-info",
                    "content": ""
                },
                {
                    "name": "-gno-column-info",
                    "content": "Emit  location column information into DWARF debugging information, rather than just file\nand line.  This option is enabled by default.\n"
                },
                {
                    "name": "-gstatement-frontiers",
                    "content": ""
                },
                {
                    "name": "-gno-statement-frontiers",
                    "content": "This option causes GCC to create markers in the internal representation at the  beginning\nof  statements,  and  to keep them roughly in place throughout compilation, using them to\nguide the output of \"isstmt\" markers in the line  number  table.   This  is  enabled  by\ndefault  when  compiling  with  optimization (-Os, -O1, -O2, ...), and outputting DWARF 2\ndebug information at the normal level.\n"
                },
                {
                    "name": "-gvariable-location-views",
                    "content": ""
                },
                {
                    "name": "-gvariable-location-views=incompat5",
                    "content": ""
                },
                {
                    "name": "-gno-variable-location-views",
                    "content": "Augment variable location lists with progressive  view  numbers  implied  from  the  line\nnumber  table.   This  enables  debug  information  consumers to inspect state at certain\npoints of the program, even if no instructions associated with the  corresponding  source\nlocations  are present at that point.  If the assembler lacks support for view numbers in\nline number tables, this will cause the compiler to emit the  line  number  table,  which\ngenerally  makes  them  somewhat  less  compact.   The  augmented  line number tables and\nlocation  lists  are  fully  backward-compatible,  so  they  can  be  consumed  by  debug\ninformation  consumers  that  are not aware of these augmentations, but they won't derive\nany benefit from them either.\n\nThis is enabled by default when outputting DWARF 2 debug information at the normal level,\nas long  as  there  is  assembler  support,  -fvar-tracking-assignments  is  enabled  and\n-gstrict-dwarf  is  not.   When  assembler  support  is  not available, this may still be\nenabled,  but  it  will  force  GCC  to  output  internal  line  number  tables,  and  if\n-ginternal-reset-location-views is not enabled, that will most certainly lead to silently\nmismatching location views.\n\nThere  is a proposed representation for view numbers that is not backward compatible with\nthe  location  list  format  introduced  in  DWARF  5,   that   can   be   enabled   with\n-gvariable-location-views=incompat5.   This  option may be removed in the future, is only\nprovided as a reference implementation of the proposed representation.  Debug information\nconsumers are not expected to support this extended format, and they  would  be  rendered\nunable to decode location lists using it.\n"
                },
                {
                    "name": "-ginternal-reset-location-views",
                    "content": ""
                },
                {
                    "name": "-gno-internal-reset-location-views",
                    "content": "Attempt  to  determine location views that can be omitted from location view lists.  This\nrequires the compiler to have very accurate insn length estimates, which isn't always the\ncase, and it may cause incorrect view lists  to  be  generated  silently  when  using  an\nassembler  that  does  not  support location view lists.  The GNU assembler will flag any\nsuch error as a \"view number mismatch\".  This is only enabled  on  ports  that  define  a\nreliable estimation function.\n"
                },
                {
                    "name": "-ginline-points",
                    "content": ""
                },
                {
                    "name": "-gno-inline-points",
                    "content": "Generate  extended  debug  information  for  inlined  functions.   Location view tracking\nmarkers are inserted at inlined entry points, so that address and  view  numbers  can  be\ncomputed  and output in debug information.  This can be enabled independently of location\nviews, in which case the view numbers won't be output, but it can only be  enabled  along\nwith  statement  frontiers,  and  it  is  only  enabled  by default if location views are\nenabled.\n"
                },
                {
                    "name": "-gz",
                    "content": "Produce compressed debug sections in DWARF format, if that is supported.  If type is  not\ngiven,  the  default  type  depends on the capabilities of the assembler and linker used.\ntype may be one of none (don't compress debug sections), or zlib (use zlib compression in\nELF gABI format).  If the linker doesn't support writing compressed debug  sections,  the\noption  is  rejected.  Otherwise, if the assembler does not support them, -gz is silently\nignored when producing object files.\n"
                },
                {
                    "name": "-femit-struct-debug-baseonly",
                    "content": "Emit debug information for struct-like types only when the base name of  the  compilation\nsource file matches the base name of file in which the struct is defined.\n\nThis  option  substantially reduces the size of debugging information, but at significant\npotential loss in type information to the debugger.  See -femit-struct-debug-reduced  for\na less aggressive option.  See -femit-struct-debug-detailed for more detailed control.\n\nThis option works only with DWARF debug output.\n"
                },
                {
                    "name": "-femit-struct-debug-reduced",
                    "content": "Emit  debug  information for struct-like types only when the base name of the compilation\nsource file matches the base name of file in which the type is defined, unless the struct\nis a template or defined in a system header.\n\nThis option significantly reduces the size of debugging information, with some  potential\nloss  in  type  information to the debugger.  See -femit-struct-debug-baseonly for a more\naggressive option.  See -femit-struct-debug-detailed for more detailed control.\n\nThis option works only with DWARF debug output.\n"
                },
                {
                    "name": "-femit-struct-debug-detailed",
                    "content": "Specify the struct-like types for which the compiler generates  debug  information.   The\nintent  is  to  reduce  duplicate struct debug information between different object files\nwithin the same program.\n\nThis   option   is   a    detailed    version    of    -femit-struct-debug-reduced    and\n-femit-struct-debug-baseonly, which serves for most needs.\n\nA specification has the syntax[dir:|ind:][ord:|gen:](any|sys|base|none)\n\nThe optional first word limits the specification to structs that are used directly (dir:)\nor  used  indirectly  (ind:).   A  struct  type is used directly when it is the type of a\nvariable, member.  Indirect uses arise through pointers to structs.  That is, when use of\nan incomplete struct is valid, the use is indirect.  An example  is  struct  one  direct;\nstruct two * indirect;.\n\nThe  optional  second word limits the specification to ordinary structs (ord:) or generic\nstructs (gen:).  Generic structs are a bit complicated to explain.  For  C++,  these  are\nnon-explicit  specializations  of  template  classes,  or non-template classes within the\nabove.  Other programming languages have generics, but -femit-struct-debug-detailed  does\nnot yet implement them.\n\nThe third word specifies the source files for those structs for which the compiler should\nemit debug information.  The values none and any have the normal meaning.  The value base\nmeans  that the base of name of the file in which the type declaration appears must match\nthe base of the name of the main compilation file.  In practice,  this  means  that  when\ncompiling  foo.c,  debug  information  is  generated  for types declared in that file and\nfoo.h, but not other header files.  The value sys means those types  satisfying  base  or\ndeclared in system or compiler headers.\n\nYou may need to experiment to determine the best settings for your application.\n\nThe default is -femit-struct-debug-detailed=all.\n\nThis option works only with DWARF debug output.\n"
                },
                {
                    "name": "-fno-dwarf2-cfi-asm",
                    "content": "Emit  DWARF  unwind  info  as compiler generated \".ehframe\" section instead of using GAS\n\".cfi*\" directives.\n"
                },
                {
                    "name": "-fno-eliminate-unused-debug-types",
                    "content": "Normally, when producing DWARF output, GCC avoids producing debug symbol output for types\nthat are nowhere used in the source file being compiled.  Sometimes it is useful to  have\nGCC  emit  debugging information for all types declared in a compilation unit, regardless\nof whether or not they are actually used in that compilation unit, for example if, in the\ndebugger, you want to cast a value to a type that is not actually used  in  your  program\n(but  is  declared).  More often, however, this results in a significant amount of wasted\nspace.\n"
                },
                {
                    "name": "Options That Control Optimization",
                    "content": "These options control various sorts of optimizations.\n\nWithout any optimization option, the compiler's goal is to reduce the cost of compilation and\nto make debugging produce the expected results.  Statements are independent: if you stop  the\nprogram with a breakpoint between statements, you can then assign a new value to any variable\nor  change  the  program  counter  to any other statement in the function and get exactly the\nresults you expect from the source code.\n\nTurning on optimization flags makes the compiler attempt to improve  the  performance  and/or\ncode size at the expense of compilation time and possibly the ability to debug the program.\n\nThe  compiler  performs optimization based on the knowledge it has of the program.  Compiling\nmultiple files at once to a single output file mode allows the compiler  to  use  information\ngained from all of the files when compiling each of them.\n\nNot all optimizations are controlled directly by a flag.  Only optimizations that have a flag\nare listed in this section.\n\nMost optimizations are completely disabled at -O0 or if an -O level is not set on the command\nline,  even  if  individual optimization flags are specified.  Similarly, -Og suppresses many\noptimization passes.\n\nDepending on the target and how GCC was configured, a slightly different set of optimizations\nmay be enabled at each -O level  than  those  listed  here.   You  can  invoke  GCC  with  -Q\n--help=optimizers to find out the exact set of optimizations that are enabled at each level.\n"
                },
                {
                    "name": "-O",
                    "content": "",
                    "flag": "-O"
                },
                {
                    "name": "-O1",
                    "content": "large function.\n\nWith -O, the compiler tries to reduce code size and execution  time,  without  performing\nany optimizations that take a great deal of compilation time.\n\n-O turns on the following optimization flags:\n\n-fauto-inc-dec      -fbranch-count-reg     -fcombine-stack-adjustments     -fcompare-elim\n-fcprop-registers   -fdce   -fdefer-pop   -fdelayed-branch   -fdse    -fforward-propagate\n-fguess-branch-probability                -fif-conversion                -fif-conversion2\n-finline-functions-called-once      -fipa-modref      -fipa-profile      -fipa-pure-const\n-fipa-reference   -fipa-reference-addressable   -fmerge-constants  -fmove-loop-invariants\n-fmove-loop-stores       -fomit-frame-pointer       -freorder-blocks        -fshrink-wrap\n-fshrink-wrap-separate   -fsplit-wide-types  -fssa-backprop  -fssa-phiopt  -ftree-bit-ccp\n-ftree-ccp      -ftree-ch      -ftree-coalesce-vars      -ftree-copy-prop      -ftree-dce\n-ftree-dominator-opts  -ftree-dse  -ftree-forwprop  -ftree-fre  -ftree-phiprop -ftree-pta\n-ftree-scev-cprop -ftree-sink -ftree-slsr -ftree-sra -ftree-ter -funit-at-a-time\n"
                },
                {
                    "name": "-O2",
                    "content": "a  space-speed  tradeoff.  As compared to -O, this option increases both compilation time\nand the performance of the generated code.\n\n-O2 turns on all optimization flags specified by -O1.  It also  turns  on  the  following\noptimization flags:\n\n-falign-functions     -falign-jumps    -falign-labels     -falign-loops    -fcaller-saves\n-fcode-hoisting        -fcrossjumping        -fcse-follow-jumps         -fcse-skip-blocks\n-fdelete-null-pointer-checks         -fdevirtualize          -fdevirtualize-speculatively\n-fexpensive-optimizations   -ffinite-loops   -fgcse    -fgcse-lm   -fhoist-adjacent-loads\n-finline-functions  -finline-small-functions  -findirect-inlining  -fipa-bit-cp  -fipa-cp\n-fipa-icf   -fipa-ra     -fipa-sra     -fipa-vrp    -fisolate-erroneous-paths-dereference\n-flra-remat  -foptimize-sibling-calls  -foptimize-strlen  -fpartial-inlining  -fpeephole2\n-freorder-blocks-algorithm=stc    -freorder-blocks-and-partition      -freorder-functions\n-frerun-cse-after-loop     -fschedule-insns      -fschedule-insns2     -fsched-interblock\n-fsched-spec  -fstore-merging  -fstrict-aliasing  -fthread-jumps  -ftree-builtin-call-dce\n-ftree-loop-vectorize     -ftree-pre     -ftree-slp-vectorize    -ftree-switch-conversion\n-ftree-tail-merge -ftree-vrp -fvect-cost-model=very-cheap\n\nPlease note the warning under -fgcse about invoking -O2 on  programs  that  use  computed\ngotos.\n\nNOTE:  In  Ubuntu 8.10 and later versions, -DFORTIFYSOURCE=2, in Ubuntu 24.04 and later\nversions, -DFORTIFYSOURCE=3, is set by default, and is activated when -O is set to 2 or\nhigher.  This enables additional  compile-time  and  run-time  checks  for  several  libc\nfunctions.  To disable, specify either -UFORTIFYSOURCE or -DFORTIFYSOURCE=0.\n\nNOTE:  In  Debian  13  and Ubuntu 24.04 and later versions, -DTIMEBITS=64 together with\n-DFILEOFFSETBITS=64 is set by default on the 32bit architectures armel,  armhf,  hppa,\nm68k, mips, mipsel, powerpc and sh4.\n"
                },
                {
                    "name": "-O3  -O3  -O2",
                    "content": "following optimization flags:\n\n-fgcse-after-reload  -fipa-cp-clone -floop-interchange -floop-unroll-and-jam -fpeel-loops\n-fpredictive-commoning     -fsplit-loops      -fsplit-paths      -ftree-loop-distribution\n-ftree-partial-pre -funswitch-loops -fvect-cost-model=dynamic -fversion-loops-for-strides\n"
                },
                {
                    "name": "-O0",
                    "content": "default.\n"
                },
                {
                    "name": "-Os  -Os  -O2",
                    "content": "code size:\n\n-falign-functions   -falign-jumps  -falign-labels   -falign-loops  -fprefetch-loop-arrays\n-freorder-blocks-algorithm=stc\n\nIt also enables -finline-functions, causes the compiler to tune for code size rather than\nexecution speed, and performs further optimizations designed to reduce code size.\n"
                },
                {
                    "name": "-Ofast",
                    "content": "Disregard strict standards compliance.  -Ofast enables all -O3  optimizations.   It  also\nenables  optimizations  that are not valid for all standard-compliant programs.  It turns\non -ffast-math, -fallow-store-data-races and the Fortran-specific -fstack-arrays,  unless\n-fmax-stack-var-size    is    specified,   and   -fno-protect-parens.    It   turns   off\n-fsemantic-interposition.\n"
                },
                {
                    "name": "-Og  -Og",
                    "content": "standard  edit-compile-debug  cycle,  offering  a  reasonable level of optimization while\nmaintaining fast compilation and a good debugging experience.  It is a better choice than\n-O0 for producing debuggable  code  because  some  compiler  passes  that  collect  debug\ninformation are disabled at -O0.\n\nLike  -O0,  -Og  completely  disables  a number of optimization passes so that individual\noptions controlling them have no effect.  Otherwise  -Og  enables  all  -O1  optimization\nflags except for those that may interfere with debugging:\n\n-fbranch-count-reg     -fdelayed-branch    -fdse     -fif-conversion     -fif-conversion2\n-finline-functions-called-once -fmove-loop-invariants   -fmove-loop-stores   -fssa-phiopt\n-ftree-bit-ccp  -ftree-dse  -ftree-pta  -ftree-sra\n"
                },
                {
                    "name": "-Oz",
                    "content": "instructions executed if those instructions require fewer bytes to encode.   -Oz  behaves\nsimilarly to -Os including enabling most -O2 optimizations.\n\nIf  you  use  multiple -O options, with or without level numbers, the last such option is the\none that is effective.\n\nOptions of the form -fflag specify machine-independent flags.  Most flags have both  positive\nand  negative forms; the negative form of -ffoo is -fno-foo.  In the table below, only one of\nthe forms is listed---the one you typically use.  You can figure out the other form by either\nremoving no- or adding it.\n\nThe following options control specific  optimizations.   They  are  either  activated  by  -O\noptions  or  are related to ones that are.  You can use the following flags in the rare cases\nwhen \"fine-tuning\" of optimizations to be performed is desired.\n"
                },
                {
                    "name": "-fno-defer-pop",
                    "content": "For machines that must pop arguments after a function call, always pop the  arguments  as\nsoon  as  each  function  returns.  At levels -O1 and higher, -fdefer-pop is the default;\nthis allows the compiler to let arguments accumulate on the stack  for  several  function\ncalls and pop them all at once.\n"
                },
                {
                    "name": "-fforward-propagate",
                    "content": "Perform  a  forward  propagation pass on RTL.  The pass tries to combine two instructions\nand checks if the result can be simplified.  If loop unrolling is active, two passes  are\nperformed and the second is scheduled after loop unrolling.\n\nThis option is enabled by default at optimization levels -O1, -O2, -O3, -Os.\n"
                },
                {
                    "name": "-ffp-contract=_",
                    "content": "-ffp-contract=off  disables  floating-point  expression  contraction.  -ffp-contract=fast\nenables floating-point expression contraction  such  as  forming  of  fused  multiply-add\noperations if the target has native support for them.  -ffp-contract=on enables floating-\npoint  expression contraction if allowed by the language standard.  This is currently not\nimplemented and treated equal to -ffp-contract=off.\n\nThe default is -ffp-contract=fast.\n"
                },
                {
                    "name": "-fomit-frame-pointer",
                    "content": "Omit the frame pointer in functions that don't need one.  This avoids the instructions to\nsave, set up and restore the frame pointer; on  many  targets  it  also  makes  an  extra\nregister available.\n\nOn some targets this flag has no effect because the standard calling sequence always uses\na frame pointer, so it cannot be omitted.\n\nNote  that  -fno-omit-frame-pointer  doesn't  guarantee  the frame pointer is used in all\nfunctions.  Several targets always omit the frame pointer in leaf functions.\n\nEnabled by default at -O1 and higher.\n"
                },
                {
                    "name": "-foptimize-sibling-calls",
                    "content": "Optimize sibling and tail recursive calls.\n\nEnabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-foptimize-strlen",
                    "content": "Optimize various standard C string functions (e.g. \"strlen\", \"strchr\"  or  \"strcpy\")  and\ntheir \"FORTIFYSOURCE\" counterparts into faster alternatives.\n\nEnabled at levels -O2, -O3.\n"
                },
                {
                    "name": "-fno-inline",
                    "content": "Do  not  expand  any  functions  inline  apart from those marked with the \"alwaysinline\"\nattribute.  This is the default when not optimizing.\n\nSingle functions can be exempted from  inlining  by  marking  them  with  the  \"noinline\"\nattribute.\n"
                },
                {
                    "name": "-finline-small-functions",
                    "content": "Integrate  functions into their callers when their body is smaller than expected function\ncall code (so overall size of program gets smaller).  The compiler heuristically  decides\nwhich  functions  are  simple  enough to be worth integrating in this way.  This inlining\napplies to all functions, even those not declared inline.\n\nEnabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-findirect-inlining",
                    "content": "Inline also indirect calls that are discovered to be known  at  compile  time  thanks  to\nprevious  inlining.  This option has any effect only when inlining itself is turned on by\nthe -finline-functions or -finline-small-functions options.\n\nEnabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-finline-functions",
                    "content": "Consider all functions for inlining, even if they are not declared inline.  The  compiler\nheuristically decides which functions are worth integrating in this way.\n\nIf  all  calls to a given function are integrated, and the function is declared \"static\",\nthen the function is normally not output as assembler code in its own right.\n\nEnabled at levels -O2, -O3, -Os.  Also enabled by -fprofile-use and -fauto-profile.\n"
                },
                {
                    "name": "-finline-functions-called-once",
                    "content": "Consider all \"static\" functions called once for inlining into their caller even  if  they\nare  not marked \"inline\".  If a call to a given function is integrated, then the function\nis not output as assembler code in its own right.\n\nEnabled at levels -O1, -O2, -O3 and -Os, but not -Og.\n"
                },
                {
                    "name": "-fearly-inlining",
                    "content": "Inline functions marked by \"alwaysinline\" and functions whose body  seems  smaller  than\nthe function call overhead early before doing -fprofile-generate instrumentation and real\ninlining  pass.   Doing  so  makes  profiling  significantly cheaper and usually inlining\nfaster on programs having large chains of nested wrapper functions.\n\nEnabled by default.\n"
                },
                {
                    "name": "-fipa-sra",
                    "content": "Perform interprocedural scalar replacement of aggregates, removal  of  unused  parameters\nand replacement of parameters passed by reference by parameters passed by value.\n\nEnabled at levels -O2, -O3 and -Os.\n"
                },
                {
                    "name": "-finline-limit=_",
                    "content": "By  default,  GCC  limits  the  size  of functions that can be inlined.  This flag allows\ncoarse control of this limit.  n is the size of functions that can be inlined  in  number\nof pseudo instructions.\n\nInlining  is  actually  controlled  by  a  number  of  parameters, which may be specified\nindividually by using --param name=value.  The -finline-limit=n option sets some of these\nparameters as follows:\n\nmax-inline-insns-single\nis set to n/2.\n\nmax-inline-insns-auto\nis set to n/2.\n\nSee below for a documentation of the individual parameters controlling inlining  and  for\nthe defaults of these parameters.\n\nNote: there may be no value to -finline-limit that results in default behavior.\n\nNote:  pseudo instruction represents, in this particular context, an abstract measurement\nof function's size.  In no way does it represent a count of assembly instructions and  as\nsuch its exact meaning might change from one release to an another.\n"
                },
                {
                    "name": "-fno-keep-inline-dllexport",
                    "content": "This  is  a  more  fine-grained version of -fkeep-inline-functions, which applies only to\nfunctions that are declared using the \"dllexport\" attribute or declspec.\n"
                },
                {
                    "name": "-fkeep-inline-functions",
                    "content": "In C, emit \"static\" functions that are declared \"inline\" into the object  file,  even  if\nthe  function  has  been  inlined  into  all of its callers.  This switch does not affect\nfunctions using the \"extern inline\" extension in GNU C90.   In  C++,  emit  any  and  all\ninline functions into the object file.\n"
                },
                {
                    "name": "-fkeep-static-functions",
                    "content": "Emit \"static\" functions into the object file, even if the function is never used.\n"
                },
                {
                    "name": "-fkeep-static-consts",
                    "content": "Emit  variables  declared  \"static  const\" when optimization isn't turned on, even if the\nvariables aren't referenced.\n\nGCC enables this option by default.  If you want to force the  compiler  to  check  if  a\nvariable  is  referenced, regardless of whether or not optimization is turned on, use the\n-fno-keep-static-consts option.\n"
                },
                {
                    "name": "-fmerge-constants",
                    "content": "Attempt to merge identical constants  (string  constants  and  floating-point  constants)\nacross compilation units.\n\nThis  option is the default for optimized compilation if the assembler and linker support\nit.  Use -fno-merge-constants to inhibit this behavior.\n\nEnabled at levels -O1, -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fmerge-all-constants",
                    "content": "Attempt to merge identical constants and identical variables.\n\nThis option implies -fmerge-constants.  In addition to -fmerge-constants  this  considers\ne.g.  even constant initialized arrays or initialized constant variables with integral or\nfloating-point types.  Languages like C or C++ require each variable, including  multiple\ninstances  of  the same variable in recursive calls, to have distinct locations, so using\nthis option results in non-conforming behavior.\n"
                },
                {
                    "name": "-fmodulo-sched",
                    "content": "Perform swing modulo scheduling immediately before the first scheduling pass.  This  pass\nlooks  at  innermost  loops  and  reorders  their  instructions  by overlapping different\niterations.\n"
                },
                {
                    "name": "-fmodulo-sched-allow-regmoves",
                    "content": "Perform more aggressive SMS-based modulo scheduling  with  register  moves  allowed.   By\nsetting  this  flag  certain  anti-dependences  edges  are  deleted,  which  triggers the\ngeneration of reg-moves based on the life-range analysis.  This option is effective  only\nwith -fmodulo-sched enabled.\n"
                },
                {
                    "name": "-fno-branch-count-reg",
                    "content": "Disable  the optimization pass that scans for opportunities to use \"decrement and branch\"\ninstructions on a count register  instead  of  instruction  sequences  that  decrement  a\nregister, compare it against zero, and then branch based upon the result.  This option is\nonly  meaningful  on  architectures  that  support  such instructions, which include x86,\nPowerPC, IA-64 and S/390.  Note that the -fno-branch-count-reg option doesn't remove  the\ndecrement  and  branch  instructions  from the generated instruction stream introduced by\nother optimization passes.\n\nThe default is -fbranch-count-reg at -O1 and higher, except for -Og.\n"
                },
                {
                    "name": "-fno-function-cse",
                    "content": "Do not put function addresses in registers; make each instruction that calls  a  constant\nfunction contain the function's address explicitly.\n\nThis  option  results  in  less  efficient  code,  but  some strange hacks that alter the\nassembler output may be confused by the optimizations performed when this option  is  not\nused.\n\nThe default is -ffunction-cse\n"
                },
                {
                    "name": "-fno-zero-initialized-in-bss",
                    "content": "If  the target supports a BSS section, GCC by default puts variables that are initialized\nto zero into BSS.  This can save space in the resulting code.\n\nThis option turns off this behavior because some programs explicitly  rely  on  variables\ngoing to the data section---e.g., so that the resulting executable can find the beginning\nof that section and/or make assumptions based on that.\n\nThe default is -fzero-initialized-in-bss.\n"
                },
                {
                    "name": "-fthread-jumps",
                    "content": "Perform  optimizations  that  check to see if a jump branches to a location where another\ncomparison subsumed by the first is found.  If so, the  first  branch  is  redirected  to\neither  the  destination  of  the  second  branch  or  a  point immediately following it,\ndepending on whether the condition is known to be true or false.\n\nEnabled at levels -O1, -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fsplit-wide-types",
                    "content": "When using a type that occupies multiple registers, such  as  \"long  long\"  on  a  32-bit\nsystem,  split  the  registers  apart  and  allocate  them  independently.  This normally\ngenerates better code for those types, but may make debugging more difficult.\n\nEnabled at levels -O1, -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fsplit-wide-types-early",
                    "content": "Fully split wide types early, instead of very late.  This option  has  no  effect  unless\n-fsplit-wide-types is turned on.\n\nThis is the default on some targets.\n"
                },
                {
                    "name": "-fcse-follow-jumps",
                    "content": "In common subexpression elimination (CSE), scan through jump instructions when the target\nof  the  jump is not reached by any other path.  For example, when CSE encounters an \"if\"\nstatement with an \"else\" clause, CSE follows the jump when the condition tested is false.\n\nEnabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fcse-skip-blocks",
                    "content": "This is similar to -fcse-follow-jumps, but causes CSE to follow jumps that  conditionally\nskip  over  blocks.   When  CSE  encounters  a simple \"if\" statement with no else clause,\n-fcse-skip-blocks causes CSE to follow the jump around the body of the \"if\".\n\nEnabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-frerun-cse-after-loop",
                    "content": "Re-run common subexpression elimination after loop optimizations are performed.\n\nEnabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fgcse",
                    "content": "Perform a global common subexpression elimination pass.  This pass also  performs  global\nconstant and copy propagation.\n\nNote:  When compiling a program using computed gotos, a GCC extension, you may get better\nrun-time performance if you disable the global common subexpression elimination  pass  by\nadding -fno-gcse to the command line.\n\nEnabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fgcse-lm",
                    "content": "When -fgcse-lm is enabled, global common subexpression elimination attempts to move loads\nthat  are  only  killed  by  stores  into  themselves.   This  allows a loop containing a\nload/store sequence to be changed to a load outside the loop, and a copy/store within the\nloop.\n\nEnabled by default when -fgcse is enabled.\n"
                },
                {
                    "name": "-fgcse-sm",
                    "content": "When -fgcse-sm is enabled, a store motion pass is run after global  common  subexpression\nelimination.   This  pass attempts to move stores out of loops.  When used in conjunction\nwith -fgcse-lm, loops containing a load/store sequence can be changed to  a  load  before\nthe loop and a store after the loop.\n\nNot enabled at any optimization level.\n"
                },
                {
                    "name": "-fgcse-las",
                    "content": "When  -fgcse-las  is enabled, the global common subexpression elimination pass eliminates\nredundant loads that come after stores to the same memory location (both partial and full\nredundancies).\n\nNot enabled at any optimization level.\n"
                },
                {
                    "name": "-fgcse-after-reload",
                    "content": "When -fgcse-after-reload is enabled, a redundant load elimination pass is performed after\nreload.  The purpose of this pass is to clean up redundant spilling.\n\nEnabled by -O3, -fprofile-use and -fauto-profile.\n"
                },
                {
                    "name": "-faggressive-loop-optimizations",
                    "content": "This option tells the loop optimizer to use language constraints to derive bounds for the\nnumber of iterations of a loop.  This assumes that loop code does  not  invoke  undefined\nbehavior  by for example causing signed integer overflows or out-of-bound array accesses.\nThe bounds for the number of iterations of a loop are used to guide  loop  unrolling  and\npeeling and loop exit test optimizations.  This option is enabled by default.\n"
                },
                {
                    "name": "-funconstrained-commons",
                    "content": "This  option  tells  the compiler that variables declared in common blocks (e.g. Fortran)\nmay later be overridden with longer trailing arrays. This prevents certain  optimizations\nthat depend on knowing the array bounds.\n"
                },
                {
                    "name": "-fcrossjumping",
                    "content": "Perform  cross-jumping  transformation.   This transformation unifies equivalent code and\nsaves code size.  The resulting code may or may not perform better  than  without  cross-\njumping.\n\nEnabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fauto-inc-dec",
                    "content": "Combine  increments or decrements of addresses with memory accesses.  This pass is always\nskipped on architectures that do not have  instructions  to  support  this.   Enabled  by\ndefault at -O1 and higher on architectures that support this.\n"
                },
                {
                    "name": "-fdce",
                    "content": "Perform dead code elimination (DCE) on RTL.  Enabled by default at -O1 and higher.\n"
                },
                {
                    "name": "-fdse",
                    "content": "Perform dead store elimination (DSE) on RTL.  Enabled by default at -O1 and higher.\n"
                },
                {
                    "name": "-fif-conversion",
                    "content": "Attempt  to  transform conditional jumps into branch-less equivalents.  This includes use\nof conditional moves, min, max, set flags and abs instructions, and some tricks doable by\nstandard arithmetics.  The use of conditional execution on chips where it is available is\ncontrolled by -fif-conversion2.\n\nEnabled at levels -O1, -O2, -O3, -Os, but not with -Og.\n"
                },
                {
                    "name": "-fif-conversion2",
                    "content": "Use conditional execution (where available) to transform conditional jumps  into  branch-\nless equivalents.\n\nEnabled at levels -O1, -O2, -O3, -Os, but not with -Og.\n"
                },
                {
                    "name": "-fdeclone-ctor-dtor",
                    "content": "The  C++  ABI  requires multiple entry points for constructors and destructors: one for a\nbase subobject, one for a complete object, and one for a virtual  destructor  that  calls\noperator  delete  afterwards.   For a hierarchy with virtual bases, the base and complete\nvariants are clones, which means two copies of the function.  With this option, the  base\nand complete variants are changed to be thunks that call a common implementation.\n\nEnabled by -Os.\n"
                },
                {
                    "name": "-fdelete-null-pointer-checks",
                    "content": "Assume  that  programs  cannot safely dereference null pointers, and that no code or data\nelement  resides  at  address  zero.   This  option  enables  simple   constant   folding\noptimizations  at all optimization levels.  In addition, other optimization passes in GCC\nuse this flag to control global dataflow analyses that eliminate useless checks for  null\npointers;  these assume that a memory access to address zero always results in a trap, so\nthat if a pointer is checked after it has already been dereferenced, it cannot be null.\n\nNote  however  that  in  some  environments   this   assumption   is   not   true.    Use\n-fno-delete-null-pointer-checks  to disable this optimization for programs that depend on\nthat behavior.\n\nThis option is enabled by default on most targets.  On Nios II ELF, it defaults  to  off.\nOn AVR and MSP430, this option is completely disabled.\n\nPasses  that  use  the  dataflow  information  are  enabled  independently  at  different\noptimization levels.\n"
                },
                {
                    "name": "-fdevirtualize",
                    "content": "Attempt to convert calls to virtual functions to direct calls.  This is done both  within\na  procedure and interprocedurally as part of indirect inlining (-findirect-inlining) and\ninterprocedural constant propagation (-fipa-cp).  Enabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fdevirtualize-speculatively",
                    "content": "Attempt to convert calls to virtual functions to speculative direct calls.  Based on  the\nanalysis  of  the  type  inheritance  graph, determine for a given call the set of likely\ntargets. If the set is small, preferably of size 1, change the call  into  a  conditional\ndeciding   between  direct  and  indirect  calls.   The  speculative  calls  enable  more\noptimizations, such as inlining.  When they seem useless after further optimization, they\nare converted back into original form.\n"
                },
                {
                    "name": "-fdevirtualize-at-ltrans",
                    "content": "Stream extra information needed for aggressive devirtualization when  running  the  link-\ntime  optimizer  in local transformation mode.  This option enables more devirtualization\nbut significantly increases the size of streamed data. For this reason it is disabled  by\ndefault.\n"
                },
                {
                    "name": "-fexpensive-optimizations",
                    "content": "Perform a number of minor optimizations that are relatively expensive.\n\nEnabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-free",
                    "content": "Attempt  to  remove redundant extension instructions.  This is especially helpful for the\nx86-64 architecture, which implicitly zero-extends in 64-bit registers after  writing  to\ntheir lower 32-bit half.\n\nEnabled for Alpha, AArch64 and x86 at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fno-lifetime-dse",
                    "content": "In  C++  the value of an object is only affected by changes within its lifetime: when the\nconstructor begins, the object has an indeterminate value, and  any  changes  during  the\nlifetime  of  the  object  are  dead  when  the object is destroyed.  Normally dead store\nelimination will take advantage of this; if your code relies on the value of  the  object\nstorage  persisting  beyond  the lifetime of the object, you can use this flag to disable\nthis optimization.  To preserve stores before the constructor starts (e.g.  because  your\noperator  new  clears  the  object  storage) but still treat the object as dead after the\ndestructor, you can  use  -flifetime-dse=1.   The  default  behavior  can  be  explicitly\nselected with -flifetime-dse=2.  -flifetime-dse=0 is equivalent to -fno-lifetime-dse.\n"
                },
                {
                    "name": "-flive-range-shrinkage",
                    "content": "Attempt  to  decrease  register  pressure through register live range shrinkage.  This is\nhelpful for fast processors with small or moderate size register sets.\n"
                },
                {
                    "name": "-fira-algorithm=_",
                    "content": "Use the  specified  coloring  algorithm  for  the  integrated  register  allocator.   The\nalgorithm  argument  can  be  priority,  which specifies Chow's priority coloring, or CB,\nwhich specifies Chaitin-Briggs coloring.  Chaitin-Briggs coloring is not implemented  for\nall architectures, but for those targets that do support it, it is the default because it\ngenerates better code.\n"
                },
                {
                    "name": "-fira-region=_",
                    "content": "Use  specified regions for the integrated register allocator.  The region argument should\nbe one of the following:\n\nall Use all loops as register allocation regions.  This can give  the  best  results  for\nmachines with a small and/or irregular register set.\n\nmixed\nUse  all  loops  except  for loops with small register pressure as the regions.  This\nvalue usually gives the best results in most cases and for most architectures, and is\nenabled by default when compiling with optimization for speed (-O, -O2, ...).\n\none Use all functions as a single region.  This typically results in  the  smallest  code\nsize, and is enabled by default for -Os or -O0.\n"
                },
                {
                    "name": "-fira-hoist-pressure",
                    "content": "Use  IRA  to  evaluate register pressure in the code hoisting pass for decisions to hoist\nexpressions.  This option usually results in smaller code, but it can slow  the  compiler\ndown.\n\nThis option is enabled at level -Os for all targets.\n"
                },
                {
                    "name": "-fira-loop-pressure",
                    "content": "Use  IRA  to  evaluate  register pressure in loops for decisions to move loop invariants.\nThis option usually results in generation of faster and smaller  code  on  machines  with\nlarge register files (>= 32 registers), but it can slow the compiler down.\n\nThis option is enabled at level -O3 for some targets.\n"
                },
                {
                    "name": "-fno-ira-share-save-slots",
                    "content": "Disable  sharing of stack slots used for saving call-used hard registers living through a\ncall.  Each hard register gets a separate stack slot, and  as  a  result  function  stack\nframes are larger.\n"
                },
                {
                    "name": "-fno-ira-share-spill-slots",
                    "content": "Disable sharing of stack slots allocated for pseudo-registers.  Each pseudo-register that\ndoes  not  get a hard register gets a separate stack slot, and as a result function stack\nframes are larger.\n"
                },
                {
                    "name": "-flra-remat",
                    "content": "Enable CFG-sensitive rematerialization in LRA.  Instead  of  loading  values  of  spilled\npseudos, LRA tries to rematerialize (recalculate) values if it is profitable.\n\nEnabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fdelayed-branch",
                    "content": "If  supported  for  the  target  machine,  attempt  to  reorder  instructions  to exploit\ninstruction slots available after delayed branch instructions.\n\nEnabled at levels -O1, -O2, -O3, -Os, but not at -Og.\n"
                },
                {
                    "name": "-fschedule-insns",
                    "content": "If supported for the  target  machine,  attempt  to  reorder  instructions  to  eliminate\nexecution  stalls  due to required data being unavailable.  This helps machines that have\nslow floating point or memory load instructions by  allowing  other  instructions  to  be\nissued until the result of the load or floating-point instruction is required.\n\nEnabled at levels -O2, -O3.\n"
                },
                {
                    "name": "-fschedule-insns2",
                    "content": "Similar  to  -fschedule-insns,  but requests an additional pass of instruction scheduling\nafter register allocation has been done.  This is especially useful on  machines  with  a\nrelatively  small  number  of registers and where memory load instructions take more than\none cycle.\n\nEnabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fno-sched-interblock",
                    "content": "Disable instruction scheduling across  basic  blocks,  which  is  normally  enabled  when\nscheduling before register allocation, i.e.  with -fschedule-insns or at -O2 or higher.\n"
                },
                {
                    "name": "-fno-sched-spec",
                    "content": "Disable  speculative  motion  of  non-load  instructions,  which is normally enabled when\nscheduling before register allocation, i.e.  with -fschedule-insns or at -O2 or higher.\n"
                },
                {
                    "name": "-fsched-pressure",
                    "content": "Enable register pressure sensitive insn scheduling before register allocation.  This only\nmakes  sense  when  scheduling  before  register  allocation  is   enabled,   i.e.   with\n-fschedule-insns  or  at  -O2  or higher.  Usage of this option can improve the generated\ncode and decrease its size by preventing register pressure increase above the  number  of\navailable hard registers and subsequent spills in register allocation.\n"
                },
                {
                    "name": "-fsched-spec-load",
                    "content": "Allow  speculative  motion  of  some  load  instructions.   This  only  makes  sense when\nscheduling before register allocation, i.e. with -fschedule-insns or at -O2 or higher.\n"
                },
                {
                    "name": "-fsched-spec-load-dangerous",
                    "content": "Allow speculative  motion  of  more  load  instructions.   This  only  makes  sense  when\nscheduling before register allocation, i.e. with -fschedule-insns or at -O2 or higher.\n"
                },
                {
                    "name": "-fsched-stalled-insns",
                    "content": ""
                },
                {
                    "name": "-fsched-stalled-insns=_",
                    "content": "Define  how  many insns (if any) can be moved prematurely from the queue of stalled insns\ninto the ready list during the second scheduling  pass.   -fno-sched-stalled-insns  means\nthat  no  insns are moved prematurely, -fsched-stalled-insns=0 means there is no limit on\nhow many queued insns can be moved prematurely.  -fsched-stalled-insns without a value is\nequivalent to -fsched-stalled-insns=1.\n"
                },
                {
                    "name": "-fsched-stalled-insns-dep",
                    "content": ""
                },
                {
                    "name": "-fsched-stalled-insns-dep=_",
                    "content": "Define how many insn groups (cycles) are examined for a dependency on a stalled insn that\nis a candidate for premature removal from the queue of stalled insns.  This has an effect\nonly during the second scheduling  pass,  and  only  if  -fsched-stalled-insns  is  used.\n-fno-sched-stalled-insns-dep     is     equivalent     to    -fsched-stalled-insns-dep=0.\n-fsched-stalled-insns-dep without a value is equivalent to -fsched-stalled-insns-dep=1.\n"
                },
                {
                    "name": "-fsched2-use-superblocks",
                    "content": "When scheduling after register allocation, use superblock scheduling.  This allows motion\nacross  basic  block  boundaries,  resulting  in  faster  schedules.   This   option   is\nexperimental, as not all machine descriptions used by GCC model the CPU closely enough to\navoid unreliable results from the algorithm.\n\nThis   only   makes   sense   when   scheduling  after  register  allocation,  i.e.  with\n-fschedule-insns2 or at -O2 or higher.\n"
                },
                {
                    "name": "-fsched-group-heuristic",
                    "content": "Enable the group heuristic in the scheduler.  This heuristic favors the instruction  that\nbelongs to a schedule group.  This is enabled by default when scheduling is enabled, i.e.\nwith -fschedule-insns or -fschedule-insns2 or at -O2 or higher.\n"
                },
                {
                    "name": "-fsched-critical-path-heuristic",
                    "content": "Enable  the critical-path heuristic in the scheduler.  This heuristic favors instructions\non the critical path.  This is enabled by default when scheduling is enabled,  i.e.  with\n-fschedule-insns or -fschedule-insns2 or at -O2 or higher.\n"
                },
                {
                    "name": "-fsched-spec-insn-heuristic",
                    "content": "Enable  the  speculative  instruction  heuristic in the scheduler.  This heuristic favors\nspeculative instructions with greater dependency weakness.  This is  enabled  by  default\nwhen scheduling is enabled, i.e.  with -fschedule-insns or -fschedule-insns2 or at -O2 or\nhigher.\n"
                },
                {
                    "name": "-fsched-rank-heuristic",
                    "content": "Enable  the  rank  heuristic  in  the  scheduler.   This heuristic favors the instruction\nbelonging to a basic block with greater size or frequency.  This is  enabled  by  default\nwhen scheduling is enabled, i.e.  with -fschedule-insns or -fschedule-insns2 or at -O2 or\nhigher.\n"
                },
                {
                    "name": "-fsched-last-insn-heuristic",
                    "content": "Enable  the  last-instruction  heuristic  in  the  scheduler.   This heuristic favors the\ninstruction that is less dependent on the last instruction scheduled.  This is enabled by\ndefault when scheduling is enabled, i.e. with -fschedule-insns or -fschedule-insns2 or at\n-O2 or higher.\n"
                },
                {
                    "name": "-fsched-dep-count-heuristic",
                    "content": "Enable the dependent-count  heuristic  in  the  scheduler.   This  heuristic  favors  the\ninstruction  that has more instructions depending on it.  This is enabled by default when\nscheduling is enabled, i.e.  with -fschedule-insns or  -fschedule-insns2  or  at  -O2  or\nhigher.\n"
                },
                {
                    "name": "-freschedule-modulo-scheduled-loops",
                    "content": "Modulo  scheduling  is  performed  before  traditional  scheduling.   If a loop is modulo\nscheduled, later scheduling passes may change its schedule.  Use this option  to  control\nthat behavior.\n"
                },
                {
                    "name": "-fselective-scheduling",
                    "content": "Schedule  instructions  using  selective scheduling algorithm.  Selective scheduling runs\ninstead of the first scheduler pass.\n"
                },
                {
                    "name": "-fselective-scheduling2",
                    "content": "Schedule instructions using selective scheduling algorithm.   Selective  scheduling  runs\ninstead of the second scheduler pass.\n"
                },
                {
                    "name": "-fsel-sched-pipelining",
                    "content": "Enable  software  pipelining of innermost loops during selective scheduling.  This option\nhas no effect unless one of -fselective-scheduling or -fselective-scheduling2  is  turned\non.\n"
                },
                {
                    "name": "-fsel-sched-pipelining-outer-loops",
                    "content": "When  pipelining  loops  during  selective  scheduling,  also pipeline outer loops.  This\noption has no effect unless -fsel-sched-pipelining is turned on.\n"
                },
                {
                    "name": "-fsemantic-interposition",
                    "content": "Some object formats, like ELF, allow interposing of symbols by the dynamic linker.   This\nmeans that for symbols exported from the DSO, the compiler cannot perform interprocedural\npropagation,  inlining  and  other  optimizations  in  anticipation  that the function or\nvariable in question may change. While this feature is useful, for  example,  to  rewrite\nmemory  allocation  functions by a debugging implementation, it is expensive in the terms\nof  code  quality.   With  -fno-semantic-interposition  the  compiler  assumes  that   if\ninterposition happens for functions the overwriting function will have precisely the same\nsemantics  (and  side  effects).   Similarly  if interposition happens for variables, the\nconstructor of the variable will be the same.  The  flag  has  no  effect  for  functions\nexplicitly  declared  inline  (where  it  is  never  allowed  for interposition to change\nsemantics) and for symbols explicitly declared weak.\n"
                },
                {
                    "name": "-fshrink-wrap",
                    "content": "Emit function prologues only before parts of the function that need it,  rather  than  at\nthe top of the function.  This flag is enabled by default at -O and higher.\n"
                },
                {
                    "name": "-fshrink-wrap-separate",
                    "content": "Shrink-wrap  separate  parts of the prologue and epilogue separately, so that those parts\nare only executed when needed.  This option is on by default, but has  no  effect  unless\n-fshrink-wrap is also turned on and the target supports this.\n"
                },
                {
                    "name": "-fcaller-saves",
                    "content": "Enable  allocation  of  values  to  registers  that  are  clobbered by function calls, by\nemitting extra instructions to save and restore the registers around  such  calls.   Such\nallocation is done only when it seems to result in better code.\n\nThis option is always enabled by default on certain machines, usually those which have no\ncall-preserved registers to use instead.\n\nEnabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fcombine-stack-adjustments",
                    "content": "Tracks  stack adjustments (pushes and pops) and stack memory references and then tries to\nfind ways to combine them.\n\nEnabled by default at -O1 and higher.\n"
                },
                {
                    "name": "-fipa-ra",
                    "content": "Use caller save registers for allocation if those registers are not used  by  any  called\nfunction.   In that case it is not necessary to save and restore them around calls.  This\nis only possible if called functions  are  part  of  same  compilation  unit  as  current\nfunction and they are compiled before it.\n\nEnabled at levels -O2, -O3, -Os, however the option is disabled if generated code will be\ninstrumented  for  profiling  (-p,  or -pg) or if callee's register usage cannot be known\nexactly (this happens on targets that do not expose prologues and epilogues in RTL).\n"
                },
                {
                    "name": "-fconserve-stack",
                    "content": "Attempt to minimize stack usage.  The compiler attempts to use less stack space, even  if\nthat  makes  the  program  slower.   This  option  implies  setting the large-stack-frame\nparameter to 100 and the large-stack-frame-growth parameter to 400.\n"
                },
                {
                    "name": "-ftree-reassoc",
                    "content": "Perform reassociation on trees.  This flag is enabled by default at -O1 and higher.\n"
                },
                {
                    "name": "-fcode-hoisting",
                    "content": "Perform code hoisting.  Code  hoisting  tries  to  move  the  evaluation  of  expressions\nexecuted  on  all  paths  to  the function exit as early as possible.  This is especially\nuseful as a code size optimization, but it often helps for code speed as well.  This flag\nis enabled by default at -O2 and higher.\n"
                },
                {
                    "name": "-ftree-pre",
                    "content": "Perform partial redundancy elimination (PRE) on trees.  This flag is enabled  by  default\nat -O2 and -O3.\n"
                },
                {
                    "name": "-ftree-partial-pre",
                    "content": "Make  partial  redundancy  elimination  (PRE)  more  aggressive.  This flag is enabled by\ndefault at -O3.\n"
                },
                {
                    "name": "-ftree-forwprop",
                    "content": "Perform forward propagation on trees.  This flag is enabled by default at -O1 and higher.\n"
                },
                {
                    "name": "-ftree-fre",
                    "content": "Perform full redundancy elimination (FRE) on trees.  The difference between FRE  and  PRE\nis  that  FRE  only  considers  expressions that are computed on all paths leading to the\nredundant computation.  This analysis  is  faster  than  PRE,  though  it  exposes  fewer\nredundancies.  This flag is enabled by default at -O1 and higher.\n"
                },
                {
                    "name": "-ftree-phiprop",
                    "content": "Perform  hoisting  of  loads from conditional pointers on trees.  This pass is enabled by\ndefault at -O1 and higher.\n"
                },
                {
                    "name": "-fhoist-adjacent-loads",
                    "content": "Speculatively hoist loads from both branches of an if-then-else if  the  loads  are  from\nadjacent  locations  in  the same structure and the target architecture has a conditional\nmove instruction.  This flag is enabled by default at -O2 and higher.\n"
                },
                {
                    "name": "-ftree-copy-prop",
                    "content": "Perform copy propagation on trees.  This pass  eliminates  unnecessary  copy  operations.\nThis flag is enabled by default at -O1 and higher.\n"
                },
                {
                    "name": "-fipa-pure-const",
                    "content": "Discover which functions are pure or constant.  Enabled by default at -O1 and higher.\n"
                },
                {
                    "name": "-fipa-reference",
                    "content": "Discover  which  static variables do not escape the compilation unit.  Enabled by default\nat -O1 and higher.\n"
                },
                {
                    "name": "-fipa-reference-addressable",
                    "content": "Discover read-only, write-only and non-addressable static variables.  Enabled by  default\nat -O1 and higher.\n"
                },
                {
                    "name": "-fipa-stack-alignment",
                    "content": "Reduce stack alignment on call sites if possible.  Enabled by default.\n"
                },
                {
                    "name": "-fipa-pta",
                    "content": "Perform  interprocedural  pointer analysis and interprocedural modification and reference\nanalysis.  This option can  cause  excessive  memory  and  compile-time  usage  on  large\ncompilation units.  It is not enabled by default at any optimization level.\n"
                },
                {
                    "name": "-fipa-profile",
                    "content": "Perform  interprocedural  profile  propagation.   The  functions  called  only  from cold\nfunctions are marked as cold. Also functions executed once (such as  \"cold\",  \"noreturn\",\nstatic constructors or destructors) are identified. Cold functions and loop less parts of\nfunctions  executed  once  are  then  optimized  for size.  Enabled by default at -O1 and\nhigher.\n"
                },
                {
                    "name": "-fipa-modref",
                    "content": "Perform interprocedural mod/ref analysis.  This optimization analyzes the side effects of\nfunctions  (memory  locations  that  are  modified  or  referenced)  and  enables  better\noptimization  across  the function call boundary.  This flag is enabled by default at -O1\nand higher.\n"
                },
                {
                    "name": "-fipa-cp",
                    "content": "Perform interprocedural constant propagation.  This optimization analyzes the program  to\ndetermine  when  values passed to functions are constants and then optimizes accordingly.\nThis optimization can substantially increase performance if the application has constants\npassed to functions.  This flag is enabled by default at -O2, -Os and -O3.   It  is  also\nenabled by -fprofile-use and -fauto-profile.\n"
                },
                {
                    "name": "-fipa-cp-clone",
                    "content": "Perform  function  cloning  to  make interprocedural constant propagation stronger.  When\nenabled, interprocedural constant propagation performs function cloning  when  externally\nvisible  function  can  be called with constant arguments.  Because this optimization can\ncreate multiple copies of functions, it may significantly increase code size (see --param\nipa-cp-unit-growth=value).  This flag is enabled by default at -O3.  It is  also  enabled\nby -fprofile-use and -fauto-profile.\n"
                },
                {
                    "name": "-fipa-bit-cp",
                    "content": "When  enabled, perform interprocedural bitwise constant propagation. This flag is enabled\nby default at -O2 and by -fprofile-use and -fauto-profile.  It requires that -fipa-cp  is\nenabled.\n"
                },
                {
                    "name": "-fipa-vrp",
                    "content": "When  enabled,  perform interprocedural propagation of value ranges. This flag is enabled\nby default at -O2. It requires that -fipa-cp is enabled.\n"
                },
                {
                    "name": "-fipa-icf",
                    "content": "Perform Identical Code Folding for functions and read-only variables.   The  optimization\nreduces code size and may disturb unwind stacks by replacing a function by equivalent one\nwith   a   different  name.  The  optimization  works  more  effectively  with  link-time\noptimization enabled.\n\nAlthough the behavior is similar to the Gold Linker's ICF optimization, GCC ICF works  on\ndifferent  levels  and  thus the optimizations are not same - there are equivalences that\nare found only by GCC and equivalences found only by Gold.\n\nThis flag is enabled by default at -O2 and -Os.\n"
                },
                {
                    "name": "-flive-patching=_",
                    "content": "Control GCC's optimizations to produce output suitable for live-patching.\n\nIf the compiler's optimization uses a function's body or information extracted  from  its\nbody  to  optimize/change  another function, the latter is called an impacted function of\nthe former.  If a function is patched, its impacted functions should be patched too.\n\nThe impacted functions are determined by the  compiler's  interprocedural  optimizations.\nFor  example,  a  caller  is impacted when inlining a function into its caller, cloning a\nfunction and changing its caller to call this  new  clone,  or  extracting  a  function's\npureness/constness information to optimize its direct or indirect callers, etc.\n\nUsually,  the more IPA optimizations enabled, the larger the number of impacted functions\nfor each function.  In order to control the number of impacted functions and more  easily\ncompute  the list of impacted function, IPA optimizations can be partially enabled at two\ndifferent levels.\n\nThe level argument should be one of the following:\n\ninline-clone\nOnly enable inlining and cloning optimizations,  which  includes  inlining,  cloning,\ninterprocedural  scalar replacement of aggregates and partial inlining.  As a result,\nwhen patching a function, all its callers  and  its  clones'  callers  are  impacted,\ntherefore need to be patched as well.\n\n-flive-patching=inline-clone    disables    the    following    optimization   flags:\n-fwhole-program  -fipa-pta  -fipa-reference  -fipa-ra -fipa-icf   -fipa-icf-functions\n-fipa-icf-variables         -fipa-bit-cp          -fipa-vrp          -fipa-pure-const\n-fipa-reference-addressable -fipa-stack-alignment -fipa-modref\n\ninline-only-static\nOnly enable inlining of static functions.   As  a  result,  when  patching  a  static\nfunction, all its callers are impacted and so need to be patched as well.\n\nIn   addition   to   all   the   flags  that  -flive-patching=inline-clone  disables,\n-flive-patching=inline-only-static disables  the  following  additional  optimization\nflags: -fipa-cp-clone  -fipa-sra  -fpartial-inlining  -fipa-cp\n\nWhen -flive-patching is specified without any value, the default value is inline-clone.\n\nThis flag is disabled by default.\n\nNote that -flive-patching is not supported with link-time optimization (-flto).\n"
                },
                {
                    "name": "-fisolate-erroneous-paths-dereference",
                    "content": "Detect  paths  that  trigger  erroneous or undefined behavior due to dereferencing a null\npointer.  Isolate those paths from the main control flow  and  turn  the  statement  with\nerroneous  or undefined behavior into a trap.  This flag is enabled by default at -O2 and\nhigher and depends on -fdelete-null-pointer-checks also being enabled.\n"
                },
                {
                    "name": "-fisolate-erroneous-paths-attribute",
                    "content": "Detect paths that trigger erroneous or undefined behavior due to a null value being  used\nin  a  way  forbidden by a \"returnsnonnull\" or \"nonnull\" attribute.  Isolate those paths\nfrom the main control flow and turn the statement with erroneous  or  undefined  behavior\ninto a trap.  This is not currently enabled, but may be enabled by -O2 in the future.\n"
                },
                {
                    "name": "-ftree-sink",
                    "content": "Perform  forward  store  motion  on  trees.   This  flag is enabled by default at -O1 and\nhigher.\n"
                },
                {
                    "name": "-ftree-bit-ccp",
                    "content": "Perform sparse conditional bit  constant  propagation  on  trees  and  propagate  pointer\nalignment  information.  This pass only operates on local scalar variables and is enabled\nby default at -O1 and higher, except for -Og.  It requires that -ftree-ccp is enabled.\n"
                },
                {
                    "name": "-ftree-ccp",
                    "content": "Perform sparse conditional constant propagation (CCP) on trees.  This pass only  operates\non local scalar variables and is enabled by default at -O1 and higher.\n"
                },
                {
                    "name": "-fssa-backprop",
                    "content": "Propagate  information about uses of a value up the definition chain in order to simplify\nthe definitions.  For example, this pass strips sign operations if the sign  of  a  value\nnever matters.  The flag is enabled by default at -O1 and higher.\n"
                },
                {
                    "name": "-fssa-phiopt",
                    "content": "Perform  pattern  matching  on  SSA PHI nodes to optimize conditional code.  This pass is\nenabled by default at -O1 and higher, except for -Og.\n"
                },
                {
                    "name": "-ftree-switch-conversion",
                    "content": "Perform conversion of simple initializations in a switch to initializations from a scalar\narray.  This flag is enabled by default at -O2 and higher.\n"
                },
                {
                    "name": "-ftree-tail-merge",
                    "content": "Look for identical code sequences.  When found, replace one with a  jump  to  the  other.\nThis  optimization  is  known  as tail merging or cross jumping.  This flag is enabled by\ndefault at -O2 and higher.  The compilation time in this pass can be limited  using  max-\ntail-merge-comparisons parameter and max-tail-merge-iterations parameter.\n"
                },
                {
                    "name": "-ftree-dce",
                    "content": "Perform dead code elimination (DCE) on trees.  This flag is enabled by default at -O1 and\nhigher.\n"
                },
                {
                    "name": "-ftree-builtin-call-dce",
                    "content": "Perform  conditional dead code elimination (DCE) for calls to built-in functions that may\nset \"errno\" but are otherwise free of side effects.  This flag is enabled by  default  at\n-O2 and higher if -Os is not also specified.\n"
                },
                {
                    "name": "-ffinite-loops",
                    "content": "Assume  that a loop with an exit will eventually take the exit and not loop indefinitely.\nThis allows the compiler to  remove  loops  that  otherwise  have  no  side-effects,  not\nconsidering eventual endless looping as such.\n\nThis option is enabled by default at -O2 for C++ with -std=c++11 or higher.\n"
                },
                {
                    "name": "-ftree-dominator-opts",
                    "content": "Perform  a  variety  of  simple  scalar  cleanups  (constant/copy propagation, redundancy\nelimination, range propagation and expression simplification) based on a  dominator  tree\ntraversal.   This  also  performs jump threading (to reduce jumps to jumps). This flag is\nenabled by default at -O1 and higher.\n"
                },
                {
                    "name": "-ftree-dse",
                    "content": "Perform dead store elimination (DSE) on trees.  A dead store is a  store  into  a  memory\nlocation  that  is  later overwritten by another store without any intervening loads.  In\nthis case the earlier store can be deleted.  This flag is enabled by default at  -O1  and\nhigher.\n"
                },
                {
                    "name": "-ftree-ch",
                    "content": "Perform   loop   header  copying  on  trees.   This  is  beneficial  since  it  increases\neffectiveness of code motion optimizations.  It  also  saves  one  jump.   This  flag  is\nenabled  by  default  at  -O1  and  higher.   It is not enabled for -Os, since it usually\nincreases code size.\n"
                },
                {
                    "name": "-ftree-loop-optimize",
                    "content": "Perform loop optimizations on trees.  This flag is enabled by default at -O1 and higher.\n"
                },
                {
                    "name": "-ftree-loop-linear",
                    "content": ""
                },
                {
                    "name": "-floop-strip-mine",
                    "content": ""
                },
                {
                    "name": "-floop-block",
                    "content": "Perform loop nest  optimizations.   Same  as  -floop-nest-optimize.   To  use  this  code\ntransformation,  GCC  has  to  be  configured with --with-isl to enable the Graphite loop\ntransformation infrastructure.\n"
                },
                {
                    "name": "-fgraphite-identity",
                    "content": "Enable the identity  transformation  for  graphite.   For  every  SCoP  we  generate  the\npolyhedral  representation and transform it back to gimple.  Using -fgraphite-identity we\ncan check the costs or benefits of the GIMPLE -> GRAPHITE -> GIMPLE transformation.  Some\nminimal optimizations are also performed by the code generator isl, like index  splitting\nand dead code elimination in loops.\n"
                },
                {
                    "name": "-floop-nest-optimize",
                    "content": "Enable the isl based loop nest optimizer.  This is a generic loop nest optimizer based on\nthe  Pluto  optimization  algorithms.  It calculates a loop structure optimized for data-\nlocality and parallelism.  This option is experimental.\n"
                },
                {
                    "name": "-floop-parallelize-all",
                    "content": "Use the Graphite data dependence analysis to identify loops  that  can  be  parallelized.\nParallelize  all  the  loops that can be analyzed to not contain loop carried dependences\nwithout checking that it is profitable to parallelize the loops.\n"
                },
                {
                    "name": "-ftree-coalesce-vars",
                    "content": "While transforming the program out of the SSA representation, attempt to  reduce  copying\nby  coalescing  versions  of  different  user-defined variables, instead of just compiler\ntemporaries.  This may severely limit the ability to debug an optimized program  compiled\nwith  -fno-var-tracking-assignments.   In  the  negated  form,  this  flag  prevents  SSA\ncoalescing of user variables.  This option is  enabled  by  default  if  optimization  is\nenabled, and it does very little otherwise.\n"
                },
                {
                    "name": "-ftree-loop-if-convert",
                    "content": "Attempt to transform conditional jumps in the innermost loops to branch-less equivalents.\nThe  intent  is  to  remove control-flow from the innermost loops in order to improve the\nability of the vectorization pass to handle these loops.  This is enabled by  default  if\nvectorization is enabled.\n"
                },
                {
                    "name": "-ftree-loop-distribution",
                    "content": "Perform  loop  distribution.   This flag can improve cache performance on big loop bodies\nand allow further loop optimizations, like  parallelization  or  vectorization,  to  take\nplace.  For example, the loop\n\nDO I = 1, N\nA(I) = B(I) + C\nD(I) = E(I) * F\nENDDO\n\nis transformed to\n\nDO I = 1, N\nA(I) = B(I) + C\nENDDO\nDO I = 1, N\nD(I) = E(I) * F\nENDDO\n\nThis  flag  is  enabled  by  default  at  -O3.   It  is also enabled by -fprofile-use and\n-fauto-profile.\n"
                },
                {
                    "name": "-ftree-loop-distribute-patterns",
                    "content": "Perform loop distribution of patterns that can be code generated with calls to a library.\nThis  flag  is  enabled  by  default  at  -O2  and  higher,  and  by  -fprofile-use   and\n-fauto-profile.\n\nThis  pass distributes the initialization loops and generates a call to memset zero.  For\nexample, the loop\n\nDO I = 1, N\nA(I) = 0\nB(I) = A(I) + I\nENDDO\n\nis transformed to\n\nDO I = 1, N\nA(I) = 0\nENDDO\nDO I = 1, N\nB(I) = A(I) + I\nENDDO\n\nand the initialization loop is transformed into a call to  memset  zero.   This  flag  is\nenabled by default at -O3.  It is also enabled by -fprofile-use and -fauto-profile.\n"
                },
                {
                    "name": "-floop-interchange",
                    "content": "Perform loop interchange outside of graphite.  This flag can improve cache performance on\nloop  nest  and allow further loop optimizations, like vectorization, to take place.  For\nexample, the loop\n\nfor (int i = 0; i < N; i++)\nfor (int j = 0; j < N; j++)\nfor (int k = 0; k < N; k++)\nc[i][j] = c[i][j] + a[i][k]*b[k][j];\n\nis transformed to\n\nfor (int i = 0; i < N; i++)\nfor (int k = 0; k < N; k++)\nfor (int j = 0; j < N; j++)\nc[i][j] = c[i][j] + a[i][k]*b[k][j];\n\nThis flag is enabled by default  at  -O3.   It  is  also  enabled  by  -fprofile-use  and\n-fauto-profile.\n"
                },
                {
                    "name": "-floop-unroll-and-jam",
                    "content": "Apply  unroll and jam transformations on feasible loops.  In a loop nest this unrolls the\nouter loop by some factor and fuses the resulting multiple inner  loops.   This  flag  is\nenabled by default at -O3.  It is also enabled by -fprofile-use and -fauto-profile.\n"
                },
                {
                    "name": "-ftree-loop-im",
                    "content": "Perform loop invariant motion on trees.  This pass moves only invariants that are hard to\nhandle  at  RTL  level (function calls, operations that expand to nontrivial sequences of\ninsns).  With -funswitch-loops it also moves operands of conditions  that  are  invariant\nout  of  the  loop,  so  that  we  can  use  just  trivial invariantness analysis in loop\nunswitching.  The pass also includes store motion.\n"
                },
                {
                    "name": "-ftree-loop-ivcanon",
                    "content": "Create a canonical counter for number of iterations in loops for which determining number\nof iterations requires complicated analysis.  Later optimizations then may determine  the\nnumber easily.  Useful especially in connection with unrolling.\n"
                },
                {
                    "name": "-ftree-scev-cprop",
                    "content": "Perform  final value replacement.  If a variable is modified in a loop in such a way that\nits value when exiting the loop can be determined using only its initial  value  and  the\nnumber  of  loop  iterations,  replace  uses  of  the  final value by such a computation,\nprovided it is sufficiently cheap.  This reduces data dependencies and may allow  further\nsimplifications.  Enabled by default at -O1 and higher.\n"
                },
                {
                    "name": "-fivopts",
                    "content": "Perform  induction variable optimizations (strength reduction, induction variable merging\nand induction variable elimination) on trees.\n"
                },
                {
                    "name": "-ftree-parallelize-loops=n",
                    "content": "Parallelize loops, i.e., split their iteration space to run in n threads.  This  is  only\npossible  for  loops  whose  iterations are independent and can be arbitrarily reordered.\nThe optimization is only profitable on multiprocessor machines, for loops that  are  CPU-\nintensive,  rather  than  constrained  e.g.  by  memory  bandwidth.   This option implies\n-pthread, and thus is only supported on targets that have support for -pthread.\n"
                },
                {
                    "name": "-ftree-pta",
                    "content": "Perform function-local points-to analysis on trees.  This flag is enabled by  default  at\n-O1 and higher, except for -Og.\n"
                },
                {
                    "name": "-ftree-sra",
                    "content": "Perform  scalar  replacement of aggregates.  This pass replaces structure references with\nscalars to prevent committing structures to memory too early.  This flag  is  enabled  by\ndefault at -O1 and higher, except for -Og.\n"
                },
                {
                    "name": "-fstore-merging",
                    "content": "Perform  merging  of  narrow  stores  to  consecutive memory addresses.  This pass merges\ncontiguous stores of immediate values narrower than a word into  fewer  wider  stores  to\nreduce  the number of instructions.  This is enabled by default at -O2 and higher as well\nas -Os.\n"
                },
                {
                    "name": "-ftree-ter",
                    "content": "Perform temporary expression replacement during the SSA->normal phase.  Single use/single\ndef temporaries are replaced at their use location with their defining expression.   This\nresults  in  non-GIMPLE  code, but gives the expanders much more complex trees to work on\nresulting in better RTL generation.  This is enabled by default at -O1 and higher.\n"
                },
                {
                    "name": "-ftree-slsr",
                    "content": "Perform straight-line strength reduction on trees.  This recognizes  related  expressions\ninvolving multiplications and replaces them by less expensive calculations when possible.\nThis is enabled by default at -O1 and higher.\n"
                },
                {
                    "name": "-ftree-vectorize",
                    "content": "Perform   vectorization   on   trees.   This   flag   enables  -ftree-loop-vectorize  and\n-ftree-slp-vectorize if not explicitly specified.\n"
                },
                {
                    "name": "-ftree-loop-vectorize",
                    "content": "Perform loop vectorization on trees. This flag is  enabled  by  default  at  -O2  and  by\n-ftree-vectorize, -fprofile-use, and -fauto-profile.\n"
                },
                {
                    "name": "-ftree-slp-vectorize",
                    "content": "Perform basic block vectorization on trees. This flag is enabled by default at -O2 and by\n-ftree-vectorize, -fprofile-use, and -fauto-profile.\n"
                },
                {
                    "name": "-ftrivial-auto-var-init=_",
                    "content": "Initialize  automatic  variables  with  either  a  pattern or with zeroes to increase the\nsecurity and predictability of a program by preventing  uninitialized  memory  disclosure\nand  use.   GCC  still  considers  an  automatic  variable  that doesn't have an explicit\ninitializer as uninitialized, -Wuninitialized  and  -Wanalyzer-use-of-uninitialized-value\nwill  still  report  warning  messages  on such automatic variables and the compiler will\nperform optimization as if the variable were uninitialized.  With this option,  GCC  will\nalso  initialize any padding of automatic variables that have structure or union types to\nzeroes.  However, the current implementation cannot initialize automatic  variables  that\nare  declared  between  the  controlling  expression  and  the  first  case of a \"switch\"\nstatement.  Using -Wtrivial-auto-var-init to report all such cases.\n\nThe three values of choice are:\n\n*   uninitialized doesn't initialize any  automatic  variables.   This  is  C  and  C++'s\ndefault.\n\n*   pattern  Initialize automatic variables with values which will likely transform logic\nbugs into crashes down the line, are easily recognized in a crash  dump  and  without\nbeing  values that programmers can rely on for useful program semantics.  The current\nvalue is byte-repeatable pattern with byte  \"0xFE\".   The  values  used  for  pattern\ninitialization might be changed in the future.\n\n*   zero Initialize automatic variables with zeroes.\n\nThe default is uninitialized.\n\nYou  can  control  this  behavior for a specific variable by using the variable attribute\n\"uninitialized\".\n"
                },
                {
                    "name": "-fvect-cost-model=_",
                    "content": "Alter the cost model used for  vectorization.   The  model  argument  should  be  one  of\nunlimited,  dynamic,  cheap or very-cheap.  With the unlimited model the vectorized code-\npath is assumed to be profitable while with the dynamic model a runtime check guards  the\nvectorized  code-path  to  enable  it  only for iteration counts that will likely execute\nfaster  than  when  executing  the  original  scalar  loop.   The  cheap  model  disables\nvectorization  of  loops  where  doing  so  would  be cost prohibitive for example due to\nrequired runtime checks for data dependence or alignment but otherwise is  equal  to  the\ndynamic  model.   The very-cheap model only allows vectorization if the vector code would\nentirely replace the scalar  code  that  is  being  vectorized.   For  example,  if  each\niteration  of  a  vectorized loop would only be able to handle exactly four iterations of\nthe scalar loop, the very-cheap model  would  only  allow  vectorization  if  the  scalar\niteration count is known to be a multiple of four.\n\nThe  default  cost  model  depends  on  other optimization flags and is either dynamic or\ncheap.\n"
                },
                {
                    "name": "-fsimd-cost-model=_",
                    "content": "Alter the cost model used  for  vectorization  of  loops  marked  with  the  OpenMP  simd\ndirective.  The model argument should be one of unlimited, dynamic, cheap.  All values of\nmodel have the same meaning as described in -fvect-cost-model and by default a cost model\ndefined with -fvect-cost-model is used.\n"
                },
                {
                    "name": "-ftree-vrp",
                    "content": "Perform  Value  Range  Propagation on trees.  This is similar to the constant propagation\npass, but instead of values, ranges of values are propagated.  This allows the optimizers\nto remove unnecessary range checks like array bound checks and null pointer checks.  This\nis enabled by default at -O2 and higher.  Null pointer check elimination is only done  if\n-fdelete-null-pointer-checks is enabled.\n"
                },
                {
                    "name": "-fsplit-paths",
                    "content": "Split paths leading to loop backedges.  This can improve dead code elimination and common\nsubexpression elimination.  This is enabled by default at -O3 and above.\n"
                },
                {
                    "name": "-fsplit-ivs-in-unroller",
                    "content": "Enables  expression  of values of induction variables in later iterations of the unrolled\nloop using the value in the first iteration.  This breaks long  dependency  chains,  thus\nimproving efficiency of the scheduling passes.\n\nA  combination  of -fweb and CSE is often sufficient to obtain the same effect.  However,\nthat is not reliable in cases where the loop body is more complicated than a single basic\nblock.  It also does not work at all on some architectures due to restrictions in the CSE\npass.\n\nThis optimization is enabled by default.\n"
                },
                {
                    "name": "-fvariable-expansion-in-unroller",
                    "content": "With this option, the compiler creates multiple  copies  of  some  local  variables  when\nunrolling a loop, which can result in superior code.\n\nThis  optimization  is  enabled  by  default for PowerPC targets, but disabled by default\notherwise.\n"
                },
                {
                    "name": "-fpartial-inlining",
                    "content": "Inline parts of functions.  This option has any  effect  only  when  inlining  itself  is\nturned on by the -finline-functions or -finline-small-functions options.\n\nEnabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fpredictive-commoning",
                    "content": "Perform  predictive commoning optimization, i.e., reusing computations (especially memory\nloads and stores) performed in previous iterations of loops.\n\nThis option  is  enabled  at  level  -O3.   It  is  also  enabled  by  -fprofile-use  and\n-fauto-profile.\n"
                },
                {
                    "name": "-fprefetch-loop-arrays",
                    "content": "If  supported  by the target machine, generate instructions to prefetch memory to improve\nthe performance of loops that access large arrays.\n\nThis option may generate better or worse  code;  results  are  highly  dependent  on  the\nstructure of loops within the source code.\n\nDisabled at level -Os.\n"
                },
                {
                    "name": "-fno-printf-return-value",
                    "content": "Do  not substitute constants for known return value of formatted output functions such as\n\"sprintf\", \"snprintf\", \"vsprintf\", and \"vsnprintf\" (but not \"printf\" of \"fprintf\").  This\ntransformation allows GCC to optimize or even  eliminate  branches  based  on  the  known\nreturn  value of these functions called with arguments that are either constant, or whose\nvalues are known to be in a range that makes determining the exact return value possible.\nFor example, when -fprintf-return-value is in effect, both the branch and the body of the\n\"if\" statement (but not the call to \"snprint\") can be optimized away when \"i\" is a 32-bit\nor smaller integer because the return value is guaranteed to be at most 8.\n\nchar buf[9];\nif (snprintf (buf, \"%08x\", i) >= sizeof buf)\n...\n\nThe -fprintf-return-value option relies on other optimizations and  yields  best  results\nwith   -O2   and   above.    It   works   in   tandem   with  the  -Wformat-overflow  and\n-Wformat-truncation options.  The -fprintf-return-value option is enabled by default.\n"
                },
                {
                    "name": "-fno-peephole",
                    "content": ""
                },
                {
                    "name": "-fno-peephole2",
                    "content": "Disable  any   machine-specific   peephole   optimizations.    The   difference   between\n-fno-peephole  and  -fno-peephole2  is  in how they are implemented in the compiler; some\ntargets use one, some use the other, a few use both.\n\n-fpeephole is enabled by default.  -fpeephole2 enabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fno-guess-branch-probability",
                    "content": "Do not guess branch probabilities using heuristics.\n\nGCC uses heuristics to guess branch probabilities if they are not provided  by  profiling\nfeedback  (-fprofile-arcs).   These  heuristics  are based on the control flow graph.  If\nsome branch probabilities are specified by \"builtinexpect\", then  the  heuristics  are\nused  to  guess  branch  probabilities for the rest of the control flow graph, taking the\n\"builtinexpect\" info into  account.   The  interactions  between  the  heuristics  and\n\"builtinexpect\"  can  be  complex,  and in some cases, it may be useful to disable the\nheuristics so that the effects of \"builtinexpect\" are easier to understand.\n\nIt  is  also  possible  to  specify  expected  probability   of   the   expression   with\n\"builtinexpectwithprobability\" built-in function.\n\nThe default is -fguess-branch-probability at levels -O, -O2, -O3, -Os.\n"
                },
                {
                    "name": "-freorder-blocks",
                    "content": "Reorder basic blocks in the compiled function in order to reduce number of taken branches\nand improve code locality.\n\nEnabled at levels -O1, -O2, -O3, -Os.\n"
                },
                {
                    "name": "-freorder-blocks-algorithm=_",
                    "content": "Use  the  specified  algorithm for basic block reordering.  The algorithm argument can be\nsimple, which does not increase code size (except sometimes due to secondary effects like\nalignment), or stc, the \"software trace cache\" algorithm, which tries to  put  all  often\nexecuted code together, minimizing the number of branches executed by making extra copies\nof code.\n\nThe default is simple at levels -O1, -Os, and stc at levels -O2, -O3.\n"
                },
                {
                    "name": "-freorder-blocks-and-partition",
                    "content": "In  addition  to  reordering  basic  blocks  in the compiled function, in order to reduce\nnumber of taken branches, partitions hot and cold basic blocks into separate sections  of\nthe assembly and .o files, to improve paging and cache locality performance.\n\nThis  optimization  is  automatically turned off in the presence of exception handling or\nunwind tables (on targets using setjump/longjump or target specific scheme), for linkonce\nsections, for functions with a user-defined section attribute  and  on  any  architecture\nthat  does  not  support  named  sections.  When -fsplit-stack is used this option is not\nenabled by default (to avoid linker errors), but may be enabled explicitly  (if  using  a\nworking linker).\n\nEnabled for x86 at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-freorder-functions",
                    "content": "Reorder  functions  in  the  object  file  in  order  to  improve code locality.  This is\nimplemented by  using  special  subsections  \".text.hot\"  for  most  frequently  executed\nfunctions  and  \".text.unlikely\"  for unlikely executed functions.  Reordering is done by\nthe linker so object file format must support named sections and linker must  place  them\nin a reasonable way.\n\nThis   option   isn't   effective   unless  you  either  provide  profile  feedback  (see\n-fprofile-arcs  for  details)  or  manually  annotate  functions  with  \"hot\"  or  \"cold\"\nattributes.\n\nEnabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fstrict-aliasing",
                    "content": "Allow  the  compiler  to  assume  the strictest aliasing rules applicable to the language\nbeing compiled.  For C (and C++), this activates  optimizations  based  on  the  type  of\nexpressions.  In particular, an object of one type is assumed never to reside at the same\naddress  as  an  object  of  a different type, unless the types are almost the same.  For\nexample, an \"unsigned int\" can alias an \"int\", but  not  a  \"void*\"  or  a  \"double\".   A\ncharacter type may alias any other type.\n\nPay special attention to code like this:\n\nunion aunion {\nint i;\ndouble d;\n};\n\nint f() {\nunion aunion t;\nt.d = 3.0;\nreturn t.i;\n}\n\nThe  practice of reading from a different union member than the one most recently written\nto (called \"type-punning\") is  common.   Even  with  -fstrict-aliasing,  type-punning  is\nallowed,  provided  the  memory  is  accessed through the union type.  So, the code above\nworks as expected.    However, this code might not:\n\nint f() {\nunion aunion t;\nint* ip;\nt.d = 3.0;\nip = &t.i;\nreturn *ip;\n}\n\nSimilarly, access by taking the address, casting the resulting pointer and  dereferencing\nthe result has undefined behavior, even if the cast uses a union type, e.g.:\n\nint f() {\ndouble d = 3.0;\nreturn ((union aunion *) &d)->i;\n}\n\nThe -fstrict-aliasing option is enabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fipa-strict-aliasing",
                    "content": "Controls whether rules of -fstrict-aliasing are applied across function boundaries.  Note\nthat if multiple functions gets inlined into a single function the memory accesses are no\nlonger considered to be crossing a function boundary.\n\nThe  -fipa-strict-aliasing  option  is  enabled  by  default  and  is  effective  only in\ncombination with -fstrict-aliasing.\n"
                },
                {
                    "name": "-falign-functions",
                    "content": ""
                },
                {
                    "name": "-falign-functions=_",
                    "content": ""
                },
                {
                    "name": "-falign-functions=_",
                    "content": ""
                },
                {
                    "name": "-falign-functions=_",
                    "content": ""
                },
                {
                    "name": "-falign-functions=_",
                    "content": "Align the start of functions to the  next  power-of-two  greater  than  or  equal  to  n,\nskipping  up  to m-1 bytes.  This ensures that at least the first m bytes of the function\ncan be fetched by the CPU without crossing an n-byte alignment boundary.\n\nIf m is not specified, it defaults to n.\n\nExamples:  -falign-functions=32  aligns  functions  to   the   next   32-byte   boundary,\n-falign-functions=24  aligns  to  the  next  32-byte boundary only if this can be done by\nskipping 23 bytes or less, -falign-functions=32:7 aligns to  the  next  32-byte  boundary\nonly if this can be done by skipping 6 bytes or less.\n\nThe   second  pair  of  n2:m2  values  allows  you  to  specify  a  secondary  alignment:\n-falign-functions=64:7:32:3 aligns to the next 64-byte boundary if this can  be  done  by\nskipping  6  bytes  or less, otherwise aligns to the next 32-byte boundary if this can be\ndone by skipping 2 bytes or less.  If m2 is not specified, it defaults to n2.\n\nSome assemblers only support this flag when n is a power of two;  in  that  case,  it  is\nrounded up.\n\n-fno-align-functions  and  -falign-functions=1 are equivalent and mean that functions are\nnot aligned.\n\nIf n is not specified or is zero, use a machine-dependent default.  The maximum allowed n\noption value is 65536.\n\nEnabled at levels -O2, -O3.\n"
                },
                {
                    "name": "-flimit-function-alignment",
                    "content": "If this option is  enabled,  the  compiler  tries  to  avoid  unnecessarily  overaligning\nfunctions.  It  attempts  to  instruct  the assembler to align by the amount specified by\n-falign-functions, but not to skip more bytes than the size of the function.\n"
                },
                {
                    "name": "-falign-labels",
                    "content": ""
                },
                {
                    "name": "-falign-labels=_",
                    "content": ""
                },
                {
                    "name": "-falign-labels=_",
                    "content": ""
                },
                {
                    "name": "-falign-labels=_",
                    "content": ""
                },
                {
                    "name": "-falign-labels=_",
                    "content": "Align all branch targets to a power-of-two boundary.\n\nParameters  of   this   option   are   analogous   to   the   -falign-functions   option.\n-fno-align-labels  and  -falign-labels=1  are  equivalent  and  mean  that labels are not\naligned.\n\nIf -falign-loops or -falign-jumps are applicable and are greater than  this  value,  then\ntheir values are used instead.\n\nIf n is not specified or is zero, use a machine-dependent default which is very likely to\nbe 1, meaning no alignment.  The maximum allowed n option value is 65536.\n\nEnabled at levels -O2, -O3.\n"
                },
                {
                    "name": "-falign-loops",
                    "content": ""
                },
                {
                    "name": "-falign-loops=_",
                    "content": ""
                },
                {
                    "name": "-falign-loops=_",
                    "content": ""
                },
                {
                    "name": "-falign-loops=_",
                    "content": ""
                },
                {
                    "name": "-falign-loops=_",
                    "content": "Align loops to a power-of-two boundary.  If the loops are executed many times, this makes\nup for any execution of the dummy padding instructions.\n\nIf -falign-labels is greater than this value, then its value is used instead.\n\nParameters   of   this   option   are   analogous   to   the   -falign-functions  option.\n-fno-align-loops and -falign-loops=1 are equivalent and mean that loops are not  aligned.\nThe maximum allowed n option value is 65536.\n\nIf n is not specified or is zero, use a machine-dependent default.\n\nEnabled at levels -O2, -O3.\n"
                },
                {
                    "name": "-falign-jumps",
                    "content": ""
                },
                {
                    "name": "-falign-jumps=_",
                    "content": ""
                },
                {
                    "name": "-falign-jumps=_",
                    "content": ""
                },
                {
                    "name": "-falign-jumps=_",
                    "content": ""
                },
                {
                    "name": "-falign-jumps=_",
                    "content": "Align branch targets to a power-of-two boundary, for branch targets where the targets can\nonly be reached by jumping.  In this case, no dummy operations need be executed.\n\nIf -falign-labels is greater than this value, then its value is used instead.\n\nParameters   of   this   option   are   analogous   to   the   -falign-functions  option.\n-fno-align-jumps and -falign-jumps=1 are equivalent and mean that loops are not aligned.\n\nIf n is not specified or is zero, use a machine-dependent default.  The maximum allowed n\noption value is 65536.\n\nEnabled at levels -O2, -O3.\n"
                },
                {
                    "name": "-fno-allocation-dce",
                    "content": "Do not remove unused C++ allocations in dead code elimination.\n"
                },
                {
                    "name": "-fallow-store-data-races",
                    "content": "Allow the compiler to perform optimizations that may introduce new data races on  stores,\nwithout proving that the variable cannot be concurrently accessed by other threads.  Does\nnot affect optimization of local data.  It is safe to use this option if it is known that\nglobal data will not be accessed by multiple threads.\n\nExamples  of  optimizations  enabled  by -fallow-store-data-races include hoisting or if-\nconversions that may cause a value that was already in memory to be re-written with  that\nsame  value.  Such re-writing is safe in a single threaded context but may be unsafe in a\nmulti-threaded context.  Note that on some processors, if-conversions may be required  in\norder to enable vectorization.\n\nEnabled at level -Ofast.\n"
                },
                {
                    "name": "-funit-at-a-time",
                    "content": "This  option  is  left  for  compatibility reasons. -funit-at-a-time has no effect, while\n-fno-unit-at-a-time implies -fno-toplevel-reorder and -fno-section-anchors.\n\nEnabled by default.\n"
                },
                {
                    "name": "-fno-toplevel-reorder",
                    "content": "Do not reorder top-level functions, variables, and \"asm\" statements.  Output them in  the\nsame  order  that  they appear in the input file.  When this option is used, unreferenced\nstatic variables are not removed.  This option is intended to support existing code  that\nrelies  on  a  particular  ordering.   For  new code, it is better to use attributes when\npossible.\n\n-ftoplevel-reorder is the default at -O1 and higher, and also at -O0 if -fsection-anchors\nis     explicitly     requested.      Additionally     -fno-toplevel-reorder      implies\n-fno-section-anchors.\n"
                },
                {
                    "name": "-funreachable-traps",
                    "content": "With this option, the compiler turns calls to \"builtinunreachable\" into traps, instead\nof using them for optimization.  This also affects any such calls implicitly generated by\nthe compiler.\n\nThis  option  has  the same effect as -fsanitize=unreachable -fsanitize-trap=unreachable,\nbut does not affect the values of those options.  If -fsanitize=unreachable  is  enabled,\nthat option takes priority over this one.\n\nThis option is enabled by default at -O0 and -Og.\n"
                },
                {
                    "name": "-fweb",
                    "content": "Constructs  webs  as  commonly  used for register allocation purposes and assign each web\nindividual pseudo register.  This allows the  register  allocation  pass  to  operate  on\npseudos  directly,  but  also strengthens several other optimization passes, such as CSE,\nloop  optimizer  and  trivial  dead  code  remover.   It  can,  however,  make  debugging\nimpossible, since variables no longer stay in a \"home register\".\n\nEnabled by default with -funroll-loops.\n"
                },
                {
                    "name": "-fwhole-program",
                    "content": "Assume  that  the  current  compilation unit represents the whole program being compiled.\nAll public functions and variables with the exception  of  \"main\"  and  those  merged  by\nattribute  \"externallyvisible\"  become static functions and in effect are optimized more\naggressively by interprocedural optimizers.\n\nWith -flto this option has a limited use.  In most cases the precise list of symbols used\nor exported from the binary  is  known  the  resolution  info  passed  to  the  link-time\noptimizer by the linker plugin.  It is still useful if no linker plugin is used or during\nincremental link step when final code is produced (with -flto -flinker-output=nolto-rel).\n"
                },
                {
                    "name": "-flto[=_",
                    "content": "This  option  runs  the  standard link-time optimizer.  When invoked with source code, it\ngenerates GIMPLE (one of GCC's internal representations) and writes  it  to  special  ELF\nsections in the object file.  When the object files are linked together, all the function\nbodies  are read from these ELF sections and instantiated as if they had been part of the\nsame translation unit.\n\nTo use the link-time optimizer, -flto and optimization options  should  be  specified  at\ncompile time and during the final link.  It is recommended that you compile all the files\nparticipating  in  the  same link with the same options and also specify those options at\nlink time.  For example:\n\ngcc -c -O2 -flto foo.c\ngcc -c -O2 -flto bar.c\ngcc -o myprog -flto -O2 foo.o bar.o\n\nThe first two invocations to GCC save a bytecode representation of  GIMPLE  into  special\nELF sections inside foo.o and bar.o.  The final invocation reads the GIMPLE bytecode from\nfoo.o  and  bar.o,  merges  the  two files into a single internal image, and compiles the\nresult as usual.  Since both foo.o and bar.o are merged into a single image, this  causes\nall the interprocedural analyses and optimizations in GCC to work across the two files as\nif  they  were a single one.  This means, for example, that the inliner is able to inline\nfunctions in bar.o into functions in foo.o and vice-versa.\n\nAnother (simpler) way to enable link-time optimization is:\n\ngcc -o myprog -flto -O2 foo.c bar.c\n\nThe above generates bytecode for foo.c and bar.c, merges  them  together  into  a  single\nGIMPLE representation and optimizes them as usual to produce myprog.\n\nThe important thing to keep in mind is that to enable link-time optimizations you need to\nuse  the  GCC  driver  to  perform  the  link step.  GCC automatically performs link-time\noptimization if any of the objects involved were compiled  with  the  -flto  command-line\noption.   You  can always override the automatic decision to do link-time optimization by\npassing -fno-lto to the link command.\n\nTo make whole program optimization effective, it  is  necessary  to  make  certain  whole\nprogram  assumptions.   The  compiler  needs  to know what functions and variables can be\naccessed by libraries  and  runtime  outside  of  the  link-time  optimized  unit.   When\nsupported  by  the linker, the linker plugin (see -fuse-linker-plugin) passes information\nto the compiler about used and externally visible symbols.  When the linker plugin is not\navailable,  -fwhole-program  should  be  used  to  allow  the  compiler  to  make   these\nassumptions, which leads to more aggressive optimization decisions.\n\nWhen a file is compiled with -flto without -fuse-linker-plugin, the generated object file\nis  larger  than a regular object file because it contains GIMPLE bytecodes and the usual\nfinal code (see -ffat-lto-objects).  This means that object files  with  LTO  information\ncan  be  linked  as  normal  object  files;  if  -fno-lto  is  passed  to  the linker, no\ninterprocedural optimizations  are  applied.   Note  that  when  -fno-fat-lto-objects  is\nenabled  the  compile  stage  is faster but you cannot perform a regular, non-LTO link on\nthem.\n\nWhen producing the final binary, GCC only applies link-time optimizations to those  files\nthat  contain bytecode.  Therefore, you can mix and match object files and libraries with\nGIMPLE bytecodes and final  object  code.   GCC  automatically  selects  which  files  to\noptimize in LTO mode and which files to link without further processing.\n\nGenerally,  options  specified  at  link  time  override those specified at compile time,\nalthough in some cases GCC attempts to infer link-time options from the settings used  to\ncompile the input files.\n\nIf  you  do  not  specify an optimization level option -O at link time, then GCC uses the\nhighest optimization level used when  compiling  the  object  files.   Note  that  it  is\ngenerally  ineffective  to specify an optimization level option only at link time and not\nat compile time, for two  reasons.   First,  compiling  without  optimization  suppresses\ncompiler  passes  that gather information needed for effective optimization at link time.\nSecond, some early optimization passes can be performed only at compile time and  not  at\nlink time.\n\nThere  are some code generation flags preserved by GCC when generating bytecodes, as they\nneed to be used during the final  link.   Currently,  the  following  options  and  their\nsettings  are  taken from the first object file that explicitly specifies them: -fcommon,\n-fexceptions, -fnon-call-exceptions, -fgnu-tm and all the -m target flags.\n\nThe following options -fPIC, -fpic, -fpie and -fPIE are combined based on  the  following\nscheme:\n\nB<-fPIC> + B<-fpic> = B<-fpic>\nB<-fPIC> + B<-fno-pic> = B<-fno-pic>\nB<-fpic/-fPIC> + (no option) = (no option)\nB<-fPIC> + B<-fPIE> = B<-fPIE>\nB<-fpic> + B<-fPIE> = B<-fpie>\nB<-fPIC/-fpic> + B<-fpie> = B<-fpie>\n\nCertain  ABI-changing flags are required to match in all compilation units, and trying to\noverride this at link time with a conflicting value is ignored.   This  includes  options\nsuch as -freg-struct-return and -fpcc-struct-return.\n\nOther  options  such  as  -ffp-contract,  -fno-strict-overflow,  -fwrapv,  -fno-trapv  or\n-fno-strict-aliasing are passed through to the link stage and merged  conservatively  for\nconflicting translation units.  Specifically -fno-strict-overflow, -fwrapv and -fno-trapv\ntake    precedence;   and   for   example   -ffp-contract=off   takes   precedence   over\n-ffp-contract=fast.  You can override them at link time.\n\nDiagnostic options such as -Wstringop-overflow are passed through to the link  stage  and\ntheir  setting  matches that of the compile-step at function granularity.  Note that this\nmatters only for diagnostics emitted during optimization.  Note that code transforms such\nas inlining can lead to warnings being enabled  or  disabled  for  regions  if  code  not\nconsistent with the setting at compile time.\n\nWhen you need to pass options to the assembler via -Wa or -Xassembler make sure to either\ncompile  such  translation  units  with  -fno-lto  or consistently use the same assembler\noptions on all translation units.  You can alternatively also specify  assembler  options\nat LTO link time.\n\nTo  enable  debug  info  generation you need to supply -g at compile time.  If any of the\ninput files at link time were built with debug info  generation  enabled  the  link  will\nenable  debug  info generation as well.  Any elaborate debug info settings like the dwarf\nlevel -gdwarf-5 need to be explicitly repeated at the  linker  command  line  and  mixing\ndifferent settings in different translation units is discouraged.\n\nIf  LTO  encounters  objects  with C linkage declared with incompatible types in separate\ntranslation units to be linked together (undefined behavior according to ISO C99  6.2.7),\na  non-fatal  diagnostic  may  be  issued.   The behavior is still undefined at run time.\nSimilar diagnostics may be raised for other languages.\n\nAnother feature of LTO is that it is possible to apply interprocedural  optimizations  on\nfiles written in different languages:\n\ngcc -c -flto foo.c\ng++ -c -flto bar.cc\ngfortran -c -flto baz.f90\ng++ -o myprog -flto -O3 foo.o bar.o baz.o -lgfortran\n\nNotice  that  the  final  link  is  done  with  g++  to get the C++ runtime libraries and\n-lgfortran is added to get the  Fortran  runtime  libraries.   In  general,  when  mixing\nlanguages  in  LTO  mode,  you  should  use  the same link command options as when mixing\nlanguages in a regular (non-LTO) compilation.\n\nIf object files containing GIMPLE bytecode are stored in a library archive, say libfoo.a,\nit is possible to extract and use them in an LTO link if you  are  using  a  linker  with\nplugin  support.   To create static libraries suitable for LTO, use gcc-ar and gcc-ranlib\ninstead of ar and ranlib; to show the symbols of object files with GIMPLE  bytecode,  use\ngcc-nm.   Those  commands  require  that ar, ranlib and nm have been compiled with plugin\nsupport.  At link time, use the flag  -fuse-linker-plugin  to  ensure  that  the  library\nparticipates in the LTO optimization process:\n\ngcc -o myprog -O2 -flto -fuse-linker-plugin a.o b.o -lfoo\n\nWith the linker plugin enabled, the linker extracts the needed GIMPLE files from libfoo.a\nand passes them on to the running GCC to make them part of the aggregated GIMPLE image to\nbe optimized.\n\nIf you are not using a linker with plugin support and/or do not enable the linker plugin,\nthen  the  objects  inside  libfoo.a  are  extracted and linked as usual, but they do not\nparticipate in the LTO optimization process.  In order to make a static library  suitable\nfor  both  LTO  optimization  and  usual  linkage,  compile  its  object files with -flto\n-ffat-lto-objects.\n\nLink-time optimizations do not require the presence of the whole program to operate.   If\nthe  program does not require any symbols to be exported, it is possible to combine -flto\nand -fwhole-program to allow  the  interprocedural  optimizers  to  use  more  aggressive\nassumptions   which   may   lead   to   improved   optimization  opportunities.   Use  of\n-fwhole-program is not needed when linker plugin is active (see -fuse-linker-plugin).\n\nThe current implementation of LTO makes no attempt to generate bytecode that is  portable\nbetween different types of hosts.  The bytecode files are versioned and there is a strict\nversion  check,  so  bytecode  files  generated in one version of GCC do not work with an\nolder or newer version of GCC.\n\nLink-time optimization does not work well with generation  of  debugging  information  on\nsystems other than those using a combination of ELF and DWARF.\n\nIf  you specify the optional n, the optimization and code generation done at link time is\nexecuted in parallel using n parallel jobs by utilizing an installed make  program.   The\nenvironment variable MAKE may be used to override the program used.\n\nYou  can  also specify -flto=jobserver to use GNU make's job server mode to determine the\nnumber of parallel jobs. This  is  useful  when  the  Makefile  calling  GCC  is  already\nexecuting in parallel.  You must prepend a + to the command recipe in the parent Makefile\nfor  this  to work.  This option likely only works if MAKE is GNU make.  Even without the\noption value, GCC tries to automatically detect a running GNU make's job server.\n\nUse -flto=auto to use GNU make's job server, if available,  or  otherwise  fall  back  to\nautodetection of the number of CPU threads present in your system.\n"
                },
                {
                    "name": "-flto-partition=_",
                    "content": "Specify  the partitioning algorithm used by the link-time optimizer.  The value is either\n1to1 to specify a partitioning mirroring the original source files or balanced to specify\npartitioning into equally sized chunks (whenever possible) or max to create new partition\nfor every symbol where possible.  Specifying none as an algorithm  disables  partitioning\nand  streaming  completely.   The default value is balanced. While 1to1 can be used as an\nworkaround for various code  ordering  issues,  the  max  partitioning  is  intended  for\ninternal testing only.  The value one specifies that exactly one partition should be used\nwhile  the  value none bypasses partitioning and executes the link-time optimization step\ndirectly from the WPA phase.\n"
                },
                {
                    "name": "-flto-compression-level=_",
                    "content": "This option specifies the level of compression used for intermediate language written  to\nLTO  object  files,  and  is  only  meaningful in conjunction with LTO mode (-flto).  GCC\ncurrently supports two LTO compression algorithms. For  zstd,  valid  values  are  0  (no\ncompression) to 19 (maximum compression), while zlib supports values from 0 to 9.  Values\noutside  this range are clamped to either minimum or maximum of the supported values.  If\nthe option is not given, a default balanced compression setting is used.\n"
                },
                {
                    "name": "-fuse-linker-plugin",
                    "content": "Enables the use of a linker plugin during link-time optimization.  This option relies  on\nplugin support in the linker, which is available in gold or in GNU ld 2.21 or newer.\n\nThis  option  enables  the extraction of object files with GIMPLE bytecode out of library\narchives. This improves the quality of optimization by exposing more code  to  the  link-\ntime  optimizer.   This information specifies what symbols can be accessed externally (by\nnon-LTO object or during  dynamic  linking).   Resulting  code  quality  improvements  on\nbinaries   (and   shared   libraries   that   use   hidden  visibility)  are  similar  to\n-fwhole-program.  See -flto for a description of the effect of this flag and how  to  use\nit.\n\nThis  option  is  enabled  by  default  when  LTO  support  in GCC is enabled and GCC was\nconfigured for use with a linker supporting plugins (GNU ld 2.21 or newer or gold).\n"
                },
                {
                    "name": "-ffat-lto-objects",
                    "content": "Fat LTO objects are object files that contain both  the  intermediate  language  and  the\nobject  code. This makes them usable for both LTO linking and normal linking. This option\nis effective only when compiling with -flto and is ignored at link time.\n\n-fno-fat-lto-objects improves compilation time over plain LTO, but requires the  complete\ntoolchain  to  be aware of LTO. It requires a linker with linker plugin support for basic\nfunctionality.  Additionally, nm, ar and ranlib need to support linker plugins to allow a\nfull-featured build environment (capable of building static libraries etc).  GCC provides\nthe gcc-ar, gcc-nm, gcc-ranlib wrappers to pass the right options to  these  tools.  With\nnon fat LTO makefiles need to be modified to use them.\n\nNote  that  modern  binutils  provide  plugin auto-load mechanism.  Installing the linker\nplugin into $libdir/bfd-plugins has the same effect as  usage  of  the  command  wrappers\n(gcc-ar, gcc-nm and gcc-ranlib).\n\nThe default is -fno-fat-lto-objects on targets with linker plugin support.\n"
                },
                {
                    "name": "-fcompare-elim",
                    "content": "After  register  allocation  and post-register allocation instruction splitting, identify\narithmetic instructions that compute processor flags similar to  a  comparison  operation\nbased on that arithmetic.  If possible, eliminate the explicit comparison operation.\n\nThis pass only applies to certain targets that cannot explicitly represent the comparison\noperation before register allocation is complete.\n\nEnabled at levels -O1, -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fcprop-registers",
                    "content": "After  register  allocation and post-register allocation instruction splitting, perform a\ncopy-propagation pass to try to reduce scheduling dependencies and occasionally eliminate\nthe copy.\n\nEnabled at levels -O1, -O2, -O3, -Os.\n"
                },
                {
                    "name": "-fprofile-correction",
                    "content": "Profiles collected using an  instrumented  binary  for  multi-threaded  programs  may  be\ninconsistent  due  to  missed  counter  updates.  When this option is specified, GCC uses\nheuristics to correct or smooth out such inconsistencies. By default, GCC emits an  error\nmessage when an inconsistent profile is detected.\n\nThis option is enabled by -fauto-profile.\n"
                },
                {
                    "name": "-fprofile-partial-training",
                    "content": "With \"-fprofile-use\" all portions of programs not executed during train run are optimized\nagressively  for  size rather than speed.  In some cases it is not practical to train all\npossible hot paths in the program. (For example, program may contain  functions  specific\nfor  a  given  hardware and trianing may not cover all hardware configurations program is\nrun on.)  With \"-fprofile-partial-training\" profile feedback  will  be  ignored  for  all\nfunctions  not executed during the train run leading them to be optimized as if they were\ncompiled without profile feedback. This leads to better performance when train run is not\nrepresentative but also leads to significantly bigger code.\n"
                },
                {
                    "name": "-fprofile-use",
                    "content": ""
                },
                {
                    "name": "-fprofile-use=_",
                    "content": "Enable profile feedback-directed optimizations, and the following optimizations, many  of\nwhich are generally profitable only with profile feedback available:\n\n-fbranch-probabilities   -fprofile-values  -funroll-loops   -fpeel-loops  -ftracer  -fvpt\n-finline-functions    -fipa-cp    -fipa-cp-clone    -fipa-bit-cp   -fpredictive-commoning\n-fsplit-loops       -funswitch-loops      -fgcse-after-reload       -ftree-loop-vectorize\n-ftree-slp-vectorize      -fvect-cost-model=dynamic       -ftree-loop-distribute-patterns\n-fprofile-reorder-functions\n\nBefore you can use this option, you must first generate profiling information.\n\nBy  default,  GCC emits an error message if the feedback profiles do not match the source\ncode.  This error can be turned into a  warning  by  using  -Wno-error=coverage-mismatch.\nNote  this may result in poorly optimized code.  Additionally, by default, GCC also emits\na warning message if the feedback profiles do not exist (see -Wmissing-profile).\n\nIf path is specified, GCC looks at the path to find the profile feedback data files.  See\n-fprofile-dir.\n"
                },
                {
                    "name": "-fauto-profile",
                    "content": ""
                },
                {
                    "name": "-fauto-profile=_",
                    "content": "Enable  sampling-based  feedback-directed optimizations, and the following optimizations,\nmany of which are generally profitable only with profile feedback available:\n\n-fbranch-probabilities  -fprofile-values -funroll-loops   -fpeel-loops   -ftracer   -fvpt\n-finline-functions    -fipa-cp    -fipa-cp-clone    -fipa-bit-cp   -fpredictive-commoning\n-fsplit-loops       -funswitch-loops      -fgcse-after-reload       -ftree-loop-vectorize\n-ftree-slp-vectorize      -fvect-cost-model=dynamic       -ftree-loop-distribute-patterns\n-fprofile-correction\n\npath is the name of a file  containing  AutoFDO  profile  information.   If  omitted,  it\ndefaults to fbdata.afdo in the current directory.\n\nProducing  an  AutoFDO  profile  data  file  requires  running your program with the perf\nutility  on  a  supported  GNU/Linux  target   system.    For   more   information,   see\n<https://perf.wiki.kernel.org/>.\n\nE.g.\n\nperf record -e brinstretired:neartaken -b -o perf.data \\\n-- yourprogram\n\nThen  use  the  creategcov  tool to convert the raw profile data to a format that can be\nused by GCC.  You must also supply the unstripped binary for your program to  this  tool.\nSee <https://github.com/google/autofdo>.\n\nE.g.\n\ncreategcov --binary=yourprogram.unstripped --profile=perf.data \\\n--gcov=profile.afdo\n\nThe  following  options control compiler behavior regarding floating-point arithmetic.  These\noptions trade off between speed and correctness.  All must be specifically enabled.\n"
                },
                {
                    "name": "-ffloat-store",
                    "content": "Do not store floating-point variables in registers, and inhibit other options that  might\nchange whether a floating-point value is taken from a register or memory.\n\nThis option prevents undesirable excess precision on machines such as the 68000 where the\nfloating  registers  (of  the  68881)  keep more precision than a \"double\" is supposed to\nhave.  Similarly for the x86 architecture.  For most programs, the excess precision  does\nonly good, but a few programs rely on the precise definition of IEEE floating point.  Use\n-ffloat-store for such programs, after modifying them to store all pertinent intermediate\ncomputations into variables.\n"
                },
                {
                    "name": "-fexcess-precision=_",
                    "content": "This option allows further control over excess precision on machines where floating-point\noperations  occur  in  a  format  with more precision or range than the IEEE standard and\ninterchange floating-point types.  By default, -fexcess-precision=fast is in effect; this\nmeans that operations may be carried out in a wider precision than the types specified in\nthe source if that would result in faster code, and it is unpredictable when rounding  to\nthe  types  specified  in  the  source  code  takes  place.   When compiling C or C++, if\n-fexcess-precision=standard  is  specified  then  excess  precision  follows  the   rules\nspecified in ISO C99 or C++; in particular, both casts and assignments cause values to be\nrounded  to  their semantic types (whereas -ffloat-store only affects assignments).  This\noption is enabled by default for C or C++ if a strict conformance option such as -std=c99\nor -std=c++17 is used.  -ffast-math enables -fexcess-precision=fast by default regardless\nof whether a strict conformance option is used.\n\n-fexcess-precision=standard is not implemented for languages other than C or C++.  On the\nx86, it has no effect if -mfpmath=sse or -mfpmath=sse+387 is  specified;  in  the  former\ncase,  IEEE  semantics  apply  without  excess  precision, and in the latter, rounding is\nunpredictable.\n"
                },
                {
                    "name": "-ffast-math",
                    "content": "Sets  the  options  -fno-math-errno,   -funsafe-math-optimizations,   -ffinite-math-only,\n-fno-rounding-math, -fno-signaling-nans, -fcx-limited-range and -fexcess-precision=fast.\n\nThis option causes the preprocessor macro \"FASTMATH\" to be defined.\n\nThis  option  is  not  turned  on  by any -O option besides -Ofast since it can result in\nincorrect output for programs that depend on an  exact  implementation  of  IEEE  or  ISO\nrules/specifications  for math functions. It may, however, yield faster code for programs\nthat do not require the guarantees of these specifications.\n"
                },
                {
                    "name": "-fno-math-errno",
                    "content": "Do not set \"errno\"  after  calling  math  functions  that  are  executed  with  a  single\ninstruction,  e.g.,  \"sqrt\".   A  program  that  relies on IEEE exceptions for math error\nhandling may  want  to  use  this  flag  for  speed  while  maintaining  IEEE  arithmetic\ncompatibility.\n\nThis option is not turned on by any -O option since it can result in incorrect output for\nprograms  that  depend on an exact implementation of IEEE or ISO rules/specifications for\nmath functions. It may, however, yield faster code for programs that do not  require  the\nguarantees of these specifications.\n\nThe default is -fmath-errno.\n\nOn Darwin systems, the math library never sets \"errno\".  There is therefore no reason for\nthe  compiler  to  consider  the  possibility  that  it might, and -fno-math-errno is the\ndefault.\n"
                },
                {
                    "name": "-funsafe-math-optimizations",
                    "content": "Allow optimizations for floating-point arithmetic that  (a)  assume  that  arguments  and\nresults are valid and (b) may violate IEEE or ANSI standards.  When used at link time, it\nmay  include libraries or startup files that change the default FPU control word or other\nsimilar optimizations.\n\nThis option is not turned on by any -O option since it can result in incorrect output for\nprograms that depend on an exact implementation of IEEE or ISO  rules/specifications  for\nmath  functions.  It may, however, yield faster code for programs that do not require the\nguarantees  of  these  specifications.   Enables  -fno-signed-zeros,  -fno-trapping-math,\n-fassociative-math and -freciprocal-math.\n\nThe default is -fno-unsafe-math-optimizations.\n"
                },
                {
                    "name": "-fassociative-math",
                    "content": "Allow  re-association  of operands in series of floating-point operations.  This violates\nthe ISO C and C++ language standard by possibly changing computation result.   NOTE:  re-\nordering  may  change  the  sign  of  zero  as  well as ignore NaNs and inhibit or create\nunderflow or overflow (and thus cannot be used on code that relies on  rounding  behavior\nlike \"(x + 252) - 252\".  May also reorder floating-point comparisons and thus may not\nbe  used  when  ordered  comparisons  are  required.   This  option  requires  that  both\n-fno-signed-zeros and -fno-trapping-math be in effect.  Moreover, it  doesn't  make  much\nsense  with  -frounding-math.  For  Fortran the option is automatically enabled when both\n-fno-signed-zeros and -fno-trapping-math are in effect.\n\nThe default is -fno-associative-math.\n"
                },
                {
                    "name": "-freciprocal-math",
                    "content": "Allow the reciprocal of a value to be used instead of  dividing  by  the  value  if  this\nenables  optimizations.   For  example \"x / y\" can be replaced with \"x * (1/y)\", which is\nuseful if \"(1/y)\" is subject to common subexpression elimination.  Note that  this  loses\nprecision and increases the number of flops operating on the value.\n\nThe default is -fno-reciprocal-math.\n"
                },
                {
                    "name": "-ffinite-math-only",
                    "content": "Allow  optimizations for floating-point arithmetic that assume that arguments and results\nare not NaNs or +-Infs.\n\nThis option is not turned on by any -O option since it can result in incorrect output for\nprograms that depend on an exact implementation of IEEE or ISO  rules/specifications  for\nmath  functions.  It may, however, yield faster code for programs that do not require the\nguarantees of these specifications.\n\nThe default is -fno-finite-math-only.\n"
                },
                {
                    "name": "-fno-signed-zeros",
                    "content": "Allow optimizations for floating-point arithmetic that ignore  the  signedness  of  zero.\nIEEE  arithmetic  specifies  the  behavior  of  distinct +0.0 and -0.0 values, which then\nprohibits  simplification  of  expressions  such   as   x+0.0   or   0.0*x   (even   with\n-ffinite-math-only).   This  option  implies  that  the  sign  of  a  zero  result  isn't\nsignificant.\n\nThe default is -fsigned-zeros.\n"
                },
                {
                    "name": "-fno-trapping-math",
                    "content": "Compile code assuming that floating-point operations cannot generate user-visible  traps.\nThese  traps  include  division  by zero, overflow, underflow, inexact result and invalid\noperation.  This option requires that -fno-signaling-nans be  in  effect.   Setting  this\noption may allow faster code if one relies on \"non-stop\" IEEE arithmetic, for example.\n\nThis  option  should never be turned on by any -O option since it can result in incorrect\noutput  for  programs  that  depend  on  an  exact  implementation   of   IEEE   or   ISO\nrules/specifications for math functions.\n\nThe default is -ftrapping-math.\n\nFuture   versions  of  GCC  may  provide  finer  control  of  this  setting  using  C99's\n\"FENVACCESS\" pragma.  This command-line option will be used along  with  -frounding-math\nto specify the default state for \"FENVACCESS\".\n"
                },
                {
                    "name": "-frounding-math",
                    "content": "Disable  transformations  and  optimizations  that assume default floating-point rounding\nbehavior.  This is round-to-zero for all  floating  point  to  integer  conversions,  and\nround-to-nearest  for  all other arithmetic truncations.  This option should be specified\nfor programs that change the FP rounding mode dynamically, or that may be executed with a\nnon-default rounding mode.  This  option  disables  constant  folding  of  floating-point\nexpressions  at  compile  time  (which  may  be affected by rounding mode) and arithmetic\ntransformations that are unsafe in the presence of sign-dependent rounding modes.\n\nThe default is -fno-rounding-math.\n\nThis option is  experimental  and  does  not  currently  guarantee  to  disable  all  GCC\noptimizations  that  are  affected  by rounding mode.  Future versions of GCC may provide\nfiner control of this setting using C99's \"FENVACCESS\" pragma.  This command-line option\nwill be used along with -ftrapping-math to specify the default state for \"FENVACCESS\".\n"
                },
                {
                    "name": "-fsignaling-nans",
                    "content": "Compile code assuming that IEEE signaling NaNs may  generate  user-visible  traps  during\nfloating-point  operations.   Setting  this option disables optimizations that may change\nthe  number  of  exceptions  visible  with   signaling   NaNs.    This   option   implies\n-ftrapping-math.\n\nThis option causes the preprocessor macro \"SUPPORTSNAN\" to be defined.\n\nThe default is -fno-signaling-nans.\n\nThis  option  is  experimental  and  does  not  currently  guarantee  to  disable all GCC\noptimizations that affect signaling NaN behavior.\n"
                },
                {
                    "name": "-fno-fp-int-builtin-inexact",
                    "content": "Do not allow the built-in functions \"ceil\",  \"floor\",  \"round\"  and  \"trunc\",  and  their\n\"float\"  and \"long double\" variants, to generate code that raises the \"inexact\" floating-\npoint exception for noninteger arguments.  ISO C99 and C11 allow these functions to raise\nthe \"inexact\" exception, but ISO/IEC TS 18661-1:2014, the C bindings to IEEE 754-2008, as\nintegrated into ISO C2X, does not allow these functions to do so.\n\nThe default is -ffp-int-builtin-inexact, allowing the exception to be raised, unless  C2X\nor a later C standard is selected.  This option does nothing unless -ftrapping-math is in\neffect.\n\nEven  if  -fno-fp-int-builtin-inexact  is  used,  if  the  functions generate a call to a\nlibrary function then the \"inexact\" exception may be raised if the library implementation\ndoes not follow TS 18661.\n"
                },
                {
                    "name": "-fsingle-precision-constant",
                    "content": "Treat floating-point constants as single precision instead of implicitly converting  them\nto double-precision constants.\n"
                },
                {
                    "name": "-fcx-limited-range",
                    "content": "When  enabled,  this  option  states  that  a  range  reduction  step  is not needed when\nperforming complex division.  Also, there is no checking whether the result of a  complex\nmultiplication  or  division is \"NaN + I*NaN\", with an attempt to rescue the situation in\nthat case.  The default is -fno-cx-limited-range, but is enabled by -ffast-math.\n\nThis option controls the default  setting  of  the  ISO  C99  \"CXLIMITEDRANGE\"  pragma.\nNevertheless, the option applies to all languages.\n"
                },
                {
                    "name": "-fcx-fortran-rules",
                    "content": "Complex  multiplication  and  division  follow Fortran rules.  Range reduction is done as\npart of complex division, but there is no  checking  whether  the  result  of  a  complex\nmultiplication  or  division is \"NaN + I*NaN\", with an attempt to rescue the situation in\nthat case.\n\nThe default is -fno-cx-fortran-rules.\n\nThe following options control optimizations that may improve performance, but are not enabled\nby any -O options.  This section includes experimental options that may produce broken code.\n"
                },
                {
                    "name": "-fbranch-probabilities",
                    "content": "After running a program compiled with -fprofile-arcs, you can compile it  a  second  time\nusing  -fbranch-probabilities, to improve optimizations based on the number of times each\nbranch was taken.  When a program  compiled  with  -fprofile-arcs  exits,  it  saves  arc\nexecution  counts to a file called sourcename.gcda for each source file.  The information\nin this data file is very dependent on the structure of the generated code, so  you  must\nuse  the  same  source code and the same optimization options for both compilations.  See\ndetails about the file naming in -fprofile-arcs.\n\nWith -fbranch-probabilities, GCC puts a REGBRPROB note on each JUMPINSN and CALLINSN.\nThese can be used to improve optimization.  Currently, they are only used in  one  place:\nin  reorg.cc,  instead  of  guessing  which  path  a  branch  is most likely to take, the\nREGBRPROB values are used to exactly determine which path is taken more often.\n\nEnabled by -fprofile-use and -fauto-profile.\n"
                },
                {
                    "name": "-fprofile-values",
                    "content": "If combined with -fprofile-arcs,  it  adds  code  so  that  some  data  about  values  of\nexpressions in the program is gathered.\n\nWith  -fbranch-probabilities,  it  reads  back the data gathered from profiling values of\nexpressions for usage in optimizations.\n\nEnabled by -fprofile-generate, -fprofile-use, and -fauto-profile.\n"
                },
                {
                    "name": "-fprofile-reorder-functions",
                    "content": "Function reordering based on profile instrumentation collects first time of execution  of\na function and orders these functions in ascending order.\n\nEnabled with -fprofile-use.\n"
                },
                {
                    "name": "-fvpt",
                    "content": "If combined with -fprofile-arcs, this option instructs the compiler to add code to gather\ninformation about values of expressions.\n\nWith  -fbranch-probabilities,  it  reads back the data gathered and actually performs the\noptimizations based on them.   Currently  the  optimizations  include  specialization  of\ndivision operations using the knowledge about the value of the denominator.\n\nEnabled with -fprofile-use and -fauto-profile.\n"
                },
                {
                    "name": "-frename-registers",
                    "content": "Attempt  to  avoid  false  dependencies in scheduled code by making use of registers left\nover after register allocation.  This optimization most benefits processors with lots  of\nregisters.   Depending on the debug information format adopted by the target, however, it\ncan make debugging impossible, since variables no longer stay in a \"home register\".\n\nEnabled by default with -funroll-loops.\n"
                },
                {
                    "name": "-fschedule-fusion",
                    "content": "Performs a target dependent pass over the instruction stream to schedule instructions  of\nsame  type  together because target machine can execute them more efficiently if they are\nadjacent to each other in the instruction flow.\n\nEnabled at levels -O2, -O3, -Os.\n"
                },
                {
                    "name": "-ftracer",
                    "content": "Perform tail duplication to enlarge superblock size.  This transformation simplifies  the\ncontrol flow of the function allowing other optimizations to do a better job.\n\nEnabled by -fprofile-use and -fauto-profile.\n"
                },
                {
                    "name": "-funroll-loops",
                    "content": "Unroll  loops  whose number of iterations can be determined at compile time or upon entry\nto   the   loop.     -funroll-loops    implies    -frerun-cse-after-loop,    -fweb    and\n-frename-registers.   It  also  turns  on complete loop peeling (i.e. complete removal of\nloops with a small constant number of iterations).  This option makes  code  larger,  and\nmay or may not make it run faster.\n\nEnabled by -fprofile-use and -fauto-profile.\n"
                },
                {
                    "name": "-funroll-all-loops",
                    "content": "Unroll  all  loops,  even  if  their  number  of iterations is uncertain when the loop is\nentered.  This usually makes programs run more slowly.   -funroll-all-loops  implies  the\nsame options as -funroll-loops.\n"
                },
                {
                    "name": "-fpeel-loops",
                    "content": "Peels  loops  for  which  there  is  enough  information that they do not roll much (from\nprofile feedback or static analysis).  It also  turns  on  complete  loop  peeling  (i.e.\ncomplete removal of loops with small constant number of iterations).\n\nEnabled by -O3, -fprofile-use, and -fauto-profile.\n"
                },
                {
                    "name": "-fmove-loop-invariants",
                    "content": "Enables  the  loop invariant motion pass in the RTL loop optimizer.  Enabled at level -O1\nand higher, except for -Og.\n"
                },
                {
                    "name": "-fmove-loop-stores",
                    "content": "Enables the loop store motion pass in the GIMPLE loop optimizer.   This  moves  invariant\nstores  to  after  the  end  of  the  loop in exchange for carrying the stored value in a\nregister across the iteration.  Note for this option to have an effect -ftree-loop-im has\nto be enabled as well.  Enabled at level -O1 and higher, except for -Og.\n"
                },
                {
                    "name": "-fsplit-loops",
                    "content": "Split a loop into two if it contains a condition that's always true for one side  of  the\niteration space and false for the other.\n\nEnabled by -fprofile-use and -fauto-profile.\n"
                },
                {
                    "name": "-funswitch-loops",
                    "content": "Move branches with loop invariant conditions out of the loop, with duplicates of the loop\non both branches (modified according to result of the condition).\n\nEnabled by -fprofile-use and -fauto-profile.\n"
                },
                {
                    "name": "-fversion-loops-for-strides",
                    "content": "If  a  loop  iterates over an array with a variable stride, create another version of the\nloop that assumes the stride is always one.  For example:\n\nfor (int i = 0; i < n; ++i)\nx[i * stride] = ...;\n\nbecomes:\n\nif (stride == 1)\nfor (int i = 0; i < n; ++i)\nx[i] = ...;\nelse\nfor (int i = 0; i < n; ++i)\nx[i * stride] = ...;\n\nThis is particularly useful for assumed-shape arrays in Fortran where  (for  example)  it\nallows  better  vectorization  assuming  contiguous  accesses.   This  flag is enabled by\ndefault at -O3.  It is also enabled by -fprofile-use and -fauto-profile.\n"
                },
                {
                    "name": "-ffunction-sections",
                    "content": ""
                },
                {
                    "name": "-fdata-sections",
                    "content": "Place each function or data item into its own section in the output file  if  the  target\nsupports  arbitrary  sections.   The  name  of  the function or the name of the data item\ndetermines the section's name in the output file.\n\nUse these options on systems where  the  linker  can  perform  optimizations  to  improve\nlocality of reference in the instruction space.  Most systems using the ELF object format\nhave  linkers  with  such optimizations.  On AIX, the linker rearranges sections (CSECTs)\nbased on the call graph.  The performance impact varies.\n\nTogether with a linker garbage collection (linker --gc-sections option) these options may\nlead to smaller statically-linked executables (after stripping).\n\nOn  ELF/DWARF  systems  these  options  do  not  degenerate  the  quality  of  the  debug\ninformation.  There could be issues with other object files/debug info formats.\n\nOnly  use  these  options  when  there  are significant benefits from doing so.  When you\nspecify these options, the assembler and linker create larger object and executable files\nand are also slower.  These options affect code generation.  They  prevent  optimizations\nby  the  compiler  and assembler using relative locations inside a translation unit since\nthe locations are unknown until link  time.   An  example  of  such  an  optimization  is\nrelaxing calls to short call instructions.\n"
                },
                {
                    "name": "-fstdarg-opt",
                    "content": "Optimize  the  prologue  of  variadic  argument  functions with respect to usage of those\narguments.\n"
                },
                {
                    "name": "-fsection-anchors",
                    "content": "Try to reduce the number of  symbolic  address  calculations  by  using  shared  \"anchor\"\nsymbols  to address nearby objects.  This transformation can help to reduce the number of\nGOT entries and GOT accesses on some targets.\n\nFor example, the implementation of the following function \"foo\":\n\nstatic int a, b, c;\nint foo (void) { return a + b + c; }\n\nusually calculates the addresses of all three variables,  but  if  you  compile  it  with\n-fsection-anchors,  it  accesses  the  variables from a common anchor point instead.  The\neffect is similar to the following pseudocode (which isn't valid C):\n\nint foo (void)\n{\nregister int *xr = &x;\nreturn xr[&a - &x] + xr[&b - &x] + xr[&c - &x];\n}\n\nNot all targets support this option.\n"
                },
                {
                    "name": "-fzero-call-used-regs=_",
                    "content": "Zero call-used registers at function  return  to  increase  program  security  by  either\nmitigating  Return-Oriented  Programming  (ROP) attacks or preventing information leakage\nthrough registers.\n\nThe possible values of choice are the same as for  the  \"zerocallusedregs\"  attribute.\nThe default is skip.\n\nYou  can  control  this  behavior for a specific function by using the function attribute\n\"zerocallusedregs\".\n\n--param name=value\nIn some places, GCC uses various constants to control the amount of optimization that  is\ndone.  For example, GCC does not inline functions that contain more than a certain number\nof  instructions.   You can control some of these constants on the command line using the\n--param option.\n\nThe names of specific parameters, and  the  meaning  of  the  values,  are  tied  to  the\ninternals of the compiler, and are subject to change without notice in future releases.\n\nIn  order  to  get  the  minimal,  maximal  and  default  values  of a parameter, use the\n--help=param -Q options.\n\nIn each case, the value is an integer.  The following choices of name are recognized  for\nall targets:\n\npredictable-branch-outcome\nWhen  branch  is predicted to be taken with probability lower than this threshold (in\npercent), then it is considered well predictable.\n\nmax-rtl-if-conversion-insns\nRTL if-conversion tries to remove conditional branches around  a  block  and  replace\nthem  with  conditionally  executed  instructions.   This parameter gives the maximum\nnumber of instructions in a block which should be considered for if-conversion.   The\ncompiler  will also use other heuristics to decide whether if-conversion is likely to\nbe profitable.\n\nmax-rtl-if-conversion-predictable-cost\nRTL if-conversion will try to remove conditional branches around a block and  replace\nthem  with  conditionally  executed  instructions.  These parameters give the maximum\npermissible cost for the sequence that would be generated by if-conversion  depending\non  whether  the branch is statically determined to be predictable or not.  The units\nfor this parameter are the same as those for the GCC internal seqcost  metric.   The\ncompiler  will  try  to  provide  a  reasonable  default for this parameter using the\nBRANCHCOST target macro.\n\nmax-crossjump-edges\nThe maximum number of incoming edges to consider for  cross-jumping.   The  algorithm\nused  by  -fcrossjumping  is  O(N^2)  in  the number of edges incoming to each block.\nIncreasing values mean more aggressive  optimization,  making  the  compilation  time\nincrease with probably small improvement in executable size.\n\nmin-crossjump-insns\nThe  minimum  number  of  instructions  that must be matched at the end of two blocks\nbefore cross-jumping is performed on them.  This value is ignored in the  case  where\nall instructions in the block being cross-jumped from are matched.\n\nmax-grow-copy-bb-insns\nThe  maximum code size expansion factor when copying basic blocks instead of jumping.\nThe expansion is relative to a jump instruction.\n\nmax-goto-duplication-insns\nThe maximum number of instructions to duplicate to a block that jumps to  a  computed\ngoto.   To  avoid  O(N^2)  behavior in a number of passes, GCC factors computed gotos\nearly in the compilation process, and unfactors  them  as  late  as  possible.   Only\ncomputed  jumps  at the end of a basic blocks with no more than max-goto-duplication-\ninsns are unfactored.\n\nmax-delay-slot-insn-search\nThe maximum number of instructions to consider when looking  for  an  instruction  to\nfill  a delay slot.  If more than this arbitrary number of instructions are searched,\nthe time savings from  filling  the  delay  slot  are  minimal,  so  stop  searching.\nIncreasing  values  mean  more  aggressive  optimization, making the compilation time\nincrease with probably small improvement in execution time.\n\nmax-delay-slot-live-search\nWhen trying to fill delay slots, the maximum number of instructions to consider  when\nsearching  for  a  block  with  valid  live  register  information.   Increasing this\narbitrarily  chosen  value  means  more  aggressive  optimization,   increasing   the\ncompilation  time.   This  parameter  should  be  removed when the delay slot code is\nrewritten to maintain the control-flow graph.\n\nmax-gcse-memory\nThe approximate maximum amount of memory in \"kB\" that can be allocated  in  order  to\nperform  the  global  common  subexpression elimination optimization.  If more memory\nthan specified is required, the optimization is not done.\n\nmax-gcse-insertion-ratio\nIf the ratio of expression insertions to deletions is larger than this value for  any\nexpression,  then RTL PRE inserts or removes the expression and thus leaves partially\nredundant computations in the instruction stream.\n\nmax-pending-list-length\nThe maximum number of pending dependencies  scheduling  allows  before  flushing  the\ncurrent  state  and  starting  over.   Large functions with few branches or calls can\ncreate excessively large lists which needlessly consume memory and resources.\n\nmax-modulo-backtrack-attempts\nThe maximum number of backtrack  attempts  the  scheduler  should  make  when  modulo\nscheduling a loop.  Larger values can exponentially increase compilation time.\n\nmax-inline-functions-called-once-loop-depth\nMaximal loop depth of a call considered by inline heuristics that tries to inline all\nfunctions called once.\n\nmax-inline-functions-called-once-insns\nMaximal estimated size of functions produced while inlining functions called once.\n\nmax-inline-insns-single\nSeveral  parameters  control  the  tree  inliner  used  in GCC.  This number sets the\nmaximum number of instructions (counted in GCC's internal representation) in a single\nfunction that the tree inliner considers for inlining.  This only  affects  functions\ndeclared inline and methods implemented in a class declaration (C++).\n\nmax-inline-insns-auto\nWhen  you  use  -finline-functions  (included  in -O3), a lot of functions that would\notherwise not be considered for inlining by the compiler are investigated.  To  those\nfunctions, a different (more restrictive) limit compared to functions declared inline\ncan be applied (--param max-inline-insns-auto).\n\nmax-inline-insns-small\nThis   is   bound   applied   to   calls   which   are   considered   relevant   with\n-finline-small-functions.\n\nmax-inline-insns-size\nThis is bound applied to calls which are optimized for  size.  Small  growth  may  be\ndesirable to anticipate optimization oppurtunities exposed by inlining.\n\nuninlined-function-insns\nNumber  of  instructions  accounted by inliner for function overhead such as function\nprologue and epilogue.\n\nuninlined-function-time\nExtra time accounted by inliner for function overhead such as time needed to  execute\nfunction prologue and epilogue.\n\ninline-heuristics-hint-percent\nThe  scale  (in  percents)  applied  to  inline-insns-single, inline-insns-single-O2,\ninline-insns-auto when inline heuristics hints that inlining is very profitable (will\nenable later optimizations).\n\nuninlined-thunk-insns\nuninlined-thunk-time\nSame as --param  uninlined-function-insns  and  --param  uninlined-function-time  but\napplied to function thunks.\n\ninline-min-speedup\nWhen  estimated  performance  improvement  of  caller  +  callee runtime exceeds this\nthreshold (in percent), the function can  be  inlined  regardless  of  the  limit  on\n--param max-inline-insns-single and --param max-inline-insns-auto.\n\nlarge-function-insns\nThe  limit  specifying  really large functions.  For functions larger than this limit\nafter inlining, inlining  is  constrained  by  --param  large-function-growth.   This\nparameter  is useful primarily to avoid extreme compilation time caused by non-linear\nalgorithms used by the back end.\n\nlarge-function-growth\nSpecifies maximal growth of large function  caused  by  inlining  in  percents.   For\nexample,  parameter  value 100 limits large function growth to 2.0 times the original\nsize.\n\nlarge-unit-insns\nThe limit specifying large translation unit.  Growth  caused  by  inlining  of  units\nlarger  than  this  limit  is limited by --param inline-unit-growth.  For small units\nthis might be too tight.  For example, consider a unit consisting of function A  that\nis  inline  and  B  that  just calls A three times.  If B is small relative to A, the\ngrowth of unit is 300\\% and yet such inlining is very sane.   For  very  large  units\nconsisting  of  small inlineable functions, however, the overall unit growth limit is\nneeded to avoid exponential explosion of code size.  Thus for smaller units, the size\nis increased to --param large-unit-insns before applying --param inline-unit-growth.\n\nlazy-modules\nMaximum number of concurrently open C++ module files when lazy loading.\n\ninline-unit-growth\nSpecifies maximal overall growth of the compilation unit  caused  by  inlining.   For\nexample,  parameter  value 20 limits unit growth to 1.2 times the original size. Cold\nfunctions (either marked cold via an  attribute  or  by  profile  feedback)  are  not\naccounted into the unit size.\n\nipa-cp-unit-growth\nSpecifies  maximal  overall  growth of the compilation unit caused by interprocedural\nconstant propagation.  For example, parameter value 10  limits  unit  growth  to  1.1\ntimes the original size.\n\nipa-cp-large-unit-insns\nThe size of translation unit that IPA-CP pass considers large.\n\nlarge-stack-frame\nThe  limit  specifying large stack frames.  While inlining the algorithm is trying to\nnot grow past this limit too much.\n\nlarge-stack-frame-growth\nSpecifies maximal growth of large stack frames caused by inlining in  percents.   For\nexample,  parameter  value  1000  limits  large  stack  frame  growth to 11 times the\noriginal size.\n\nmax-inline-insns-recursive\nmax-inline-insns-recursive-auto\nSpecifies the maximum number of instructions an out-of-line copy of a  self-recursive\ninline function can grow into by performing recursive inlining.\n\n--param   max-inline-insns-recursive  applies  to  functions  declared  inline.   For\nfunctions   not   declared   inline,   recursive   inlining   happens    only    when\n-finline-functions  (included in -O3) is enabled; --param max-inline-insns-recursive-\nauto applies instead.\n\nmax-inline-recursive-depth\nmax-inline-recursive-depth-auto\nSpecifies the maximum recursion depth used for recursive inlining.\n\n--param  max-inline-recursive-depth  applies  to  functions  declared  inline.    For\nfunctions    not    declared   inline,   recursive   inlining   happens   only   when\n-finline-functions (included in -O3) is enabled; --param  max-inline-recursive-depth-\nauto applies instead.\n\nmin-inline-recursive-probability\nRecursive  inlining  is profitable only for function having deep recursion in average\nand can hurt for function having little recursion depth by  increasing  the  prologue\nsize or complexity of function body to other optimizers.\n\nWhen  profile  feedback  is  available  (see -fprofile-generate) the actual recursion\ndepth can be guessed from the probability that function recurses  via  a  given  call\nexpression.    This   parameter  limits  inlining  only  to  call  expressions  whose\nprobability exceeds the given threshold (in percents).\n\nearly-inlining-insns\nSpecify growth that the early inliner can make.  In effect it increases the amount of\ninlining for code having a large abstraction penalty.\n\nmax-early-inliner-iterations\nLimit of iterations of the early inliner.  This basically bounds the number of nested\nindirect calls the early inliner can resolve.  Deeper chains  are  still  handled  by\nlate inlining.\n\ncomdat-sharing-probability\nProbability  (in  percent) that C++ inline function with comdat visibility are shared\nacross multiple compilation units.\n\nmodref-max-bases\nmodref-max-refs\nmodref-max-accesses\nSpecifies the maximal number of base pointers, references and accesses stored  for  a\nsingle function by mod/ref analysis.\n\nmodref-max-tests\nSpecifies  the maxmal number of tests alias oracle can perform to disambiguate memory\nlocations using the mod/ref information.  This parameter  ought  to  be  bigger  than\n--param modref-max-bases and --param modref-max-refs.\n\nmodref-max-depth\nSpecifies the maximum depth of DFS walk used by modref escape analysis.  Setting to 0\ndisables the analysis completely.\n\nmodref-max-escape-points\nSpecifies the maximum number of escape points tracked by modref per SSA-name.\n\nmodref-max-adjustments\nSpecifies  the  maximum  number  the  access range is enlarged during modref dataflow\nanalysis.\n\nprofile-func-internal-id\nA parameter to control whether to  use  function  internal  id  in  profile  database\nlookup.  If  the  value  is  0,  the  compiler  uses  an id that is based on function\nassembler name and filename, which makes old profile data  more  tolerant  to  source\nchanges such as function reordering etc.\n\nmin-vect-loop-bound\nThe  minimum  number  of  iterations  under  which  loops  are  not  vectorized  when\n-ftree-vectorize is used.  The number of iterations after vectorization needs  to  be\ngreater than the value specified by this option to allow vectorization.\n\ngcse-cost-distance-ratio\nScaling  factor in calculation of maximum distance an expression can be moved by GCSE\noptimizations.  This is currently supported only in  the  code  hoisting  pass.   The\nbigger the ratio, the more aggressive code hoisting is with simple expressions, i.e.,\nthe  expressions  that  have  cost  less  than  gcse-unrestricted-cost.  Specifying 0\ndisables hoisting of simple expressions.\n\ngcse-unrestricted-cost\nCost, roughly measured as the cost of a single typical machine instruction, at  which\nGCSE  optimizations  do not constrain the distance an expression can travel.  This is\ncurrently supported only in the code hoisting pass.  The lesser the  cost,  the  more\naggressive  code  hoisting  is.   Specifying  0  allows  all  expressions  to  travel\nunrestricted distances.\n\nmax-hoist-depth\nThe depth of search in the dominator tree for expressions to hoist.  This is used  to\navoid quadratic behavior in hoisting algorithm.  The value of 0 does not limit on the\nsearch, but may slow down compilation of huge functions.\n\nmax-tail-merge-comparisons\nThe  maximum  amount  of  similar  bbs  to  compare a bb with.  This is used to avoid\nquadratic behavior in tree tail merging.\n\nmax-tail-merge-iterations\nThe maximum amount of iterations of the pass over the  function.   This  is  used  to\nlimit compilation time in tree tail merging.\n\nstore-merging-allow-unaligned\nAllow the store merging pass to introduce unaligned stores if it is legal to do so.\n\nmax-stores-to-merge\nThe  maximum  number  of  stores  to  attempt to merge into wider stores in the store\nmerging pass.\n\nmax-store-chains-to-track\nThe maximum number of store chains to track at the same time in the attempt to  merge\nthem into wider stores in the store merging pass.\n\nmax-stores-to-track\nThe maximum number of stores to track at the same time in the attemt to to merge them\ninto wider stores in the store merging pass.\n\nmax-unrolled-insns\nThe maximum number of instructions that a loop may have to be unrolled.  If a loop is\nunrolled, this parameter also determines how many times the loop code is unrolled.\n\nmax-average-unrolled-insns\nThe  maximum number of instructions biased by probabilities of their execution that a\nloop may have to be unrolled.  If a loop is unrolled, this parameter also  determines\nhow many times the loop code is unrolled.\n\nmax-unroll-times\nThe maximum number of unrollings of a single loop.\n\nmax-peeled-insns\nThe  maximum  number of instructions that a loop may have to be peeled.  If a loop is\npeeled, this parameter also determines how many times the loop code is peeled.\n\nmax-peel-times\nThe maximum number of peelings of a single loop.\n\nmax-peel-branches\nThe maximum number of branches on the hot path through the peeled sequence.\n\nmax-completely-peeled-insns\nThe maximum number of insns of a completely peeled loop.\n\nmax-completely-peel-times\nThe maximum number of iterations of a loop to be suitable for complete peeling.\n\nmax-completely-peel-loop-nest-depth\nThe maximum depth of a loop nest suitable for complete peeling.\n\nmax-unswitch-insns\nThe maximum number of insns of an unswitched loop.\n\nmax-unswitch-depth\nThe maximum depth of a loop nest to be unswitched.\n\nlim-expensive\nThe minimum cost of an expensive expression in the loop invariant motion.\n\nmin-loop-cond-split-prob\nWhen FDO profile information is available, min-loop-cond-split-prob specifies minimum\nthreshold for probability of  semi-invariant  condition  statement  to  trigger  loop\nsplit.\n\niv-consider-all-candidates-bound\nBound on number of candidates for induction variables, below which all candidates are\nconsidered  for  each  use  in  induction  variable optimizations.  If there are more\ncandidates than this, only the most relevant ones are considered to  avoid  quadratic\ntime complexity.\n\niv-max-considered-uses\nThe  induction  variable  optimizations  give up on loops that contain more induction\nvariable uses.\n\niv-always-prune-cand-set-bound\nIf the number of candidates in the set is smaller than  this  value,  always  try  to\nremove unnecessary ivs from the set when adding a new one.\n\navg-loop-niter\nAverage number of iterations of a loop.\n\ndse-max-object-size\nMaximum  size  (in  bytes)  of  objects  tracked  bytewise by dead store elimination.\nLarger values may result in larger compilation times.\n\ndse-max-alias-queries-per-store\nMaximum number of queries into the alias oracle per store.  Larger values  result  in\nlarger compilation times and may result in more removed dead stores.\n\nscev-max-expr-size\nBound  on  size  of  expressions  used  in  the  scalar  evolutions  analyzer.  Large\nexpressions slow the analyzer.\n\nscev-max-expr-complexity\nBound on the complexity  of  the  expressions  in  the  scalar  evolutions  analyzer.\nComplex expressions slow the analyzer.\n\nmax-tree-if-conversion-phi-args\nMaximum  number of arguments in a PHI supported by TREE if conversion unless the loop\nis marked with simd pragma.\n\nvect-max-layout-candidates\nThe maximum number of possible vector layouts (such as permutations) to consider when\noptimizing to-be-vectorized code.\n\nvect-max-version-for-alignment-checks\nThe maximum number  of  run-time  checks  that  can  be  performed  when  doing  loop\nversioning for alignment in the vectorizer.\n\nvect-max-version-for-alias-checks\nThe  maximum  number  of  run-time  checks  that  can  be  performed  when doing loop\nversioning for alias in the vectorizer.\n\nvect-max-peeling-for-alignment\nThe maximum number of loop peels to enhance access alignment for vectorizer. Value -1\nmeans no limit.\n\nmax-iterations-to-track\nThe maximum number of iterations of a loop the brute-force algorithm for analysis  of\nthe number of iterations of the loop tries to evaluate.\n\nhot-bb-count-fraction\nThe  denominator n of fraction 1/n of the maximal execution count of a basic block in\nthe entire program that a basic  block  needs  to  at  least  have  in  order  to  be\nconsidered  hot.   The default is 10000, which means that a basic block is considered\nhot if its execution count is greater than 1/10000 of the maximal execution count.  0\nmeans that it is never considered hot.  Used in non-LTO mode.\n\nhot-bb-count-ws-permille\nThe number of most executed permilles, ranging  from  0  to  1000,  of  the  profiled\nexecution of the entire program to which the execution count of a basic block must be\npart  of in order to be considered hot.  The default is 990, which means that a basic\nblock is considered  hot  if  its  execution  count  contributes  to  the  upper  990\npermilles,  or  99.0%, of the profiled execution of the entire program.  0 means that\nit is never considered hot.  Used in LTO mode.\n\nhot-bb-frequency-fraction\nThe denominator n of fraction 1/n of the execution frequency of the entry block of  a\nfunction  that  a  basic block of this function needs to at least have in order to be\nconsidered hot.  The default is 1000, which means that a basic  block  is  considered\nhot  in  a function if it is executed more frequently than 1/1000 of the frequency of\nthe entry block of the function.  0 means that it is never considered hot.\n\nunlikely-bb-count-fraction\nThe denominator n of fraction 1/n of the  number  of  profiled  runs  of  the  entire\nprogram  below  which  the  execution count of a basic block must be in order for the\nbasic block to be considered unlikely executed.  The default is 20, which means  that\na  basic  block is considered unlikely executed if it is executed in fewer than 1/20,\nor 5%, of the runs of the program.  0 means that it  is  always  considered  unlikely\nexecuted.\n\nmax-predicted-iterations\nThe maximum number of loop iterations we predict statically.  This is useful in cases\nwhere  a  function  contains  a  single  loop  with known bound and another loop with\nunknown bound.  The known number of iterations  is  predicted  correctly,  while  the\nunknown number of iterations average to roughly 10.  This means that the loop without\nbounds appears artificially cold relative to the other one.\n\nbuiltin-expect-probability\nControl  the probability of the expression having the specified value. This parameter\ntakes a percentage (i.e. 0 ... 100) as input.\n\nbuiltin-string-cmp-inline-length\nThe maximum length of a constant string for a builtin string cmp  call  eligible  for\ninlining.\n\nalign-threshold\nSelect fraction of the maximal frequency of executions of a basic block in a function\nto align the basic block.\n\nalign-loop-iterations\nA loop expected to iterate at least the selected number of iterations is aligned.\n\ntracer-dynamic-coverage\ntracer-dynamic-coverage-feedback\nThis  value  is  used  to  limit  superblock  formation  once the given percentage of\nexecuted instructions is covered.  This limits unnecessary code size expansion.\n\nThe tracer-dynamic-coverage-feedback parameter is used only when profile feedback  is\navailable.  The real profiles (as opposed to statically estimated ones) are much less\nbalanced allowing the threshold to be larger value.\n\ntracer-max-code-growth\nStop  tail  duplication  once  code  growth  has reached given percentage.  This is a\nrather artificial limit, as most of the duplicates  are  eliminated  later  in  cross\njumping, so it may be set to much higher values than is the desired code growth.\n\ntracer-min-branch-ratio\nStop  reverse  growth  when  the  reverse  probability of best edge is less than this\nthreshold (in percent).\n\ntracer-min-branch-probability\ntracer-min-branch-probability-feedback\nStop forward growth if the best edge has probability lower than this threshold.\n\nSimilarly to tracer-dynamic-coverage two parameters are provided.  tracer-min-branch-\nprobability-feedback is used for compilation with profile  feedback  and  tracer-min-\nbranch-probability  compilation  without.   The  value  for  compilation with profile\nfeedback needs to be more conservative (higher) in order to make tracer effective.\n\nstack-clash-protection-guard-size\nSpecify the size of the operating system provided stack guard  as  2  raised  to  num\nbytes.   Higher  values  may reduce the number of explicit probes, but a value larger\nthan the operating system provided guard will leave code vulnerable  to  stack  clash\nstyle attacks.\n\nstack-clash-protection-probe-interval\nStack  clash  protection involves probing stack space as it is allocated.  This param\ncontrols the maximum distance between probes into the stack as 2 raised to num bytes.\nHigher values may reduce the number of explicit probes, but a value larger  than  the\noperating  system  provided  guard  will  leave  code vulnerable to stack clash style\nattacks.\n\nmax-cse-path-length\nThe maximum number of basic blocks on path that CSE considers.\n\nmax-cse-insns\nThe maximum number of instructions CSE processes before flushing.\n\nggc-min-expand\nGCC uses a garbage collector to manage its own  memory  allocation.   This  parameter\nspecifies  the  minimum  percentage  by  which the garbage collector's heap should be\nallowed to expand between collections.  Tuning this may improve compilation speed; it\nhas no effect on code generation.\n\nThe default is 30% + 70% * (RAM/1GB) with an upper bound of 100% when RAM >= 1GB.  If\n\"getrlimit\" is available, the notion of \"RAM\" is  the  smallest  of  actual  RAM  and\n\"RLIMITDATA\"  or  \"RLIMITAS\".   If GCC is not able to calculate RAM on a particular\nplatform, the lower bound of 30%  is  used.   Setting  this  parameter  and  ggc-min-\nheapsize  to  zero  causes  a full collection to occur at every opportunity.  This is\nextremely slow, but can be useful for debugging.\n\nggc-min-heapsize\nMinimum size of the garbage collector's heap before it begins  bothering  to  collect\ngarbage.   The  first  collection  occurs  after  the heap expands by ggc-min-expand%\nbeyond ggc-min-heapsize.  Again, tuning this may improve compilation speed,  and  has\nno effect on code generation.\n\nThe default is the smaller of RAM/8, RLIMITRSS, or a limit that tries to ensure that\nRLIMITDATA  or  RLIMITAS  are  not  exceeded,  but with a lower bound of 4096 (four\nmegabytes) and an upper bound of 131072 (128 megabytes).   If  GCC  is  not  able  to\ncalculate  RAM  on  a  particular  platform,  the  lower bound is used.  Setting this\nparameter very large effectively disables garbage collection.  Setting this parameter\nand ggc-min-expand to zero causes a full collection to occur at every opportunity.\n\nmax-reload-search-insns\nThe maximum  number  of  instruction  reload  should  look  backward  for  equivalent\nregister.    Increasing   values   mean  more  aggressive  optimization,  making  the\ncompilation time increase with probably slightly better performance.\n\nmax-cselib-memory-locations\nThe maximum number of memory locations cselib should take into  account.   Increasing\nvalues  mean  more aggressive optimization, making the compilation time increase with\nprobably slightly better performance.\n\nmax-sched-ready-insns\nThe maximum number of instructions ready to be issued the scheduler  should  consider\nat  any  given  time  during  the first scheduling pass.  Increasing values mean more\nthorough searches, making the compilation time increase with probably little benefit.\n\nmax-sched-region-blocks\nThe maximum number of blocks in a region to be considered for interblock scheduling.\n\nmax-pipeline-region-blocks\nThe maximum number of blocks in a region to  be  considered  for  pipelining  in  the\nselective scheduler.\n\nmax-sched-region-insns\nThe maximum number of insns in a region to be considered for interblock scheduling.\n\nmax-pipeline-region-insns\nThe  maximum  number  of  insns  in  a  region to be considered for pipelining in the\nselective scheduler.\n\nmin-spec-prob\nThe minimum probability (in percents) of  reaching  a  source  block  for  interblock\nspeculative scheduling.\n\nmax-sched-extend-regions-iters\nThe  maximum  number  of  iterations  through  CFG  to  extend regions.  A value of 0\ndisables region extensions.\n\nmax-sched-insn-conflict-delay\nThe maximum conflict delay for an insn to be considered for speculative motion.\n\nsched-spec-prob-cutoff\nThe minimal probability of speculation success (in  percents),  so  that  speculative\ninsns are scheduled.\n\nsched-state-edge-prob-cutoff\nThe  minimum probability an edge must have for the scheduler to save its state across\nit.\n\nsched-mem-true-dep-cost\nMinimal distance (in CPU  cycles)  between  store  and  load  targeting  same  memory\nlocations.\n\nselsched-max-lookahead\nThe  maximum  size of the lookahead window of selective scheduling.  It is a depth of\nsearch for available instructions.\n\nselsched-max-sched-times\nThe maximum number of  times  that  an  instruction  is  scheduled  during  selective\nscheduling.   This  is  the  limit  on  the  number  of  iterations through which the\ninstruction may be pipelined.\n\nselsched-insns-to-rename\nThe maximum number of best instructions in the ready list  that  are  considered  for\nrenaming in the selective scheduler.\n\nsms-min-sc\nThe minimum value of stage count that swing modulo scheduler generates.\n\nmax-last-value-rtl\nThe  maximum size measured as number of RTLs that can be recorded in an expression in\ncombiner for a pseudo register as last known value of that register.\n\nmax-combine-insns\nThe maximum number of instructions the RTL combiner tries to combine.\n\ninteger-share-limit\nSmall integer constants can use a shared  data  structure,  reducing  the  compiler's\nmemory  usage  and  increasing  its  speed.   This sets the maximum value of a shared\ninteger constant.\n\nssp-buffer-size\nThe minimum size of buffers (i.e. arrays) that receive stack smashing protection when\n-fstack-protector is used.\n\nThis default before Ubuntu 10.10 was \"8\". Currently it is \"4\", to increase the number\nof functions protected by the stack protector.\n\nmin-size-for-stack-sharing\nThe minimum size of variables taking part in stack slot sharing when not optimizing.\n\nmax-jump-thread-duplication-stmts\nMaximum number of statements allowed in a block that  needs  to  be  duplicated  when\nthreading jumps.\n\nmax-jump-thread-paths\nThe   maximum  number  of  paths  to  consider  when  searching  for  jump  threading\nopportunities.  When arriving at a block, incoming edges are only considered  if  the\nnumber of paths to be searched so far multiplied by the number of incoming edges does\nnot exhaust the specified maximum number of paths to consider.\n\nmax-fields-for-field-sensitive\nMaximum  number  of  fields in a structure treated in a field sensitive manner during\npointer analysis.\n\nprefetch-latency\nEstimate on  average  number  of  instructions  that  are  executed  before  prefetch\nfinishes.    The   distance  prefetched  ahead  is  proportional  to  this  constant.\nIncreasing  this  number  may  also  lead  to  less  streams  being  prefetched  (see\nsimultaneous-prefetches).\n\nsimultaneous-prefetches\nMaximum number of prefetches that can run at the same time.\n\nl1-cache-line-size\nThe size of cache line in L1 data cache, in bytes.\n\nl1-cache-size\nThe size of L1 data cache, in kilobytes.\n\nl2-cache-size\nThe size of L2 data cache, in kilobytes.\n\nprefetch-dynamic-strides\nWhether the loop array prefetch pass should issue software prefetch hints for strides\nthat  are  non-constant.   In  some cases this may be beneficial, though the fact the\nstride is non-constant may make it hard to predict when there  is  clear  benefit  to\nissuing these hints.\n\nSet  to  1 if the prefetch hints should be issued for non-constant strides.  Set to 0\nif prefetch hints should be issued only for strides that are known to be constant and\nbelow prefetch-minimum-stride.\n\nprefetch-minimum-stride\nMinimum constant stride, in bytes, to start using prefetch hints for.  If the  stride\nis less than this threshold, prefetch hints will not be issued.\n\nThis  setting  is useful for processors that have hardware prefetchers, in which case\nthere may be conflicts between the hardware prefetchers and the software prefetchers.\nIf the hardware prefetchers have a maximum stride they can handle, it should be  used\nhere to improve the use of software prefetchers.\n\nA  value  of  -1  means we don't have a threshold and therefore prefetch hints can be\nissued for any constant stride.\n\nThis setting is only useful for strides that are known and constant.\n\ndestructive-interference-size\nconstructive-interference-size\nThe values for the C++17 variables \"std::hardwaredestructiveinterferencesize\"  and\n\"std::hardwareconstructiveinterferencesize\".  The destructive interference size is\nthe minimum recommended offset between two independent concurrently-accessed objects;\nthe  constructive  interference  size  is  the maximum recommended size of contiguous\nmemory accessed together.  Typically both will be the size of an L1  cache  line  for\nthe  target, in bytes.  For a generic target covering a range of L1 cache line sizes,\ntypically the constructive interference size will be the small end of the  range  and\nthe destructive size will be the large end.\n\nThe destructive interference size is intended to be used for layout, and thus has ABI\nimpact.   The  default value is not expected to be stable, and on some targets varies\nwith -mtune, so use of this variable in a context where ABI stability  is  important,\nsuch  as the public interface of a library, is strongly discouraged; if it is used in\nthat context, users can stabilize the value using this option.\n\nThe constructive interference size is less sensitive, as it is typically only used in\na staticassert to make sure that a type fits within a cache line.\n\nSee also -Winterference-size.\n\nloop-interchange-max-num-stmts\nThe maximum number of stmts in a loop to be interchanged.\n\nloop-interchange-stride-ratio\nThe minimum ratio between stride of two loops for interchange to be profitable.\n\nmin-insn-to-prefetch-ratio\nThe minimum ratio between the number of instructions and the number of prefetches  to\nenable prefetching in a loop.\n\nprefetch-min-insn-to-mem-ratio\nThe  minimum  ratio  between  the  number  of  instructions  and the number of memory\nreferences to enable prefetching in a loop.\n\nuse-canonical-types\nWhether the compiler should use the \"canonical\" type system.   Should  always  be  1,\nwhich  uses  a  more  efficient  internal  mechanism  for  comparing types in C++ and\nObjective-C++.  However, if bugs in the canonical type system are causing compilation\nfailures, set this value to 0 to disable canonical types.\n\nswitch-conversion-max-branch-ratio\nSwitch initialization conversion refuses  to  create  arrays  that  are  bigger  than\nswitch-conversion-max-branch-ratio times the number of branches in the switch.\n\nmax-partial-antic-length\nMaximum  length  of the partial antic set computed during the tree partial redundancy\nelimination optimization (-ftree-pre) when optimizing at -O3  and  above.   For  some\nsorts of source code the enhanced partial redundancy elimination optimization can run\naway, consuming all of the memory available on the host machine.  This parameter sets\na  limit  on  the  length  of  the sets that are computed, which prevents the runaway\nbehavior.  Setting a value of 0 for this parameter allows an unlimited set length.\n\nrpo-vn-max-loop-depth\nMaximum loop depth that is value-numbered optimistically.  When the  limit  hits  the\ninnermost  rpo-vn-max-loop-depth  loops  and  the outermost loop in the loop nest are\nvalue-numbered optimistically and the remaining ones not.\n\nsccvn-max-alias-queries-per-access\nMaximum number of alias-oracle queries we perform when looking for  redundancies  for\nloads  and  stores.  If this limit is hit the search is aborted and the load or store\nis not considered redundant.  The number of queries is algorithmically limited to the\nnumber of stores on all paths from the load to the function entry.\n\nira-max-loops-num\nIRA uses regional register allocation by default.  If a function contains more  loops\nthan  the  number  given by this parameter, only at most the given number of the most\nfrequently-executed loops form regions for regional register allocation.\n\nira-max-conflict-table-size\nAlthough IRA uses a sophisticated algorithm to compress the conflict table, the table\ncan still require excessive amounts of memory for huge functions.   If  the  conflict\ntable  for  a function could be more than the size in MB given by this parameter, the\nregister allocator instead uses a faster, simpler, and lower-quality  algorithm  that\ndoes not require building a pseudo-register conflict table.\n\nira-loop-reserved-regs\nIRA can be used to evaluate more accurate register pressure in loops for decisions to\nmove  loop invariants (see -O3).  The number of available registers reserved for some\nother purposes is given by this parameter.  Default of  the  parameter  is  the  best\nfound from numerous experiments.\n\nira-consider-dup-in-all-alts\nMake  IRA  to consider matching constraint (duplicated operand number) heavily in all\navailable alternatives for preferred register class.  If it is set as zero, it  means\nIRA only respects the matching constraint when it's in the only available alternative\nwith an appropriate register class.  Otherwise, it means IRA will check all available\nalternatives  for  preferred  register class even if it has found some choice with an\nappropriate register class and respect the found qualified matching constraint.\n\nira-simple-lra-insn-threshold\nApproximate function insn number in 1K units triggering simple local RA.\n\nlra-inheritance-ebb-probability-cutoff\nLRA  tries  to  reuse  values  reloaded  in  registers  in  subsequent  insns.   This\noptimization is called inheritance.  EBB is used as a region to do this optimization.\nThe  parameter  defines a minimal fall-through edge probability in percentage used to\nadd BB to inheritance EBB in LRA.  The default value was chosen from numerous runs of\nSPEC2000 on x86-64.\n\nloop-invariant-max-bbs-in-loop\nLoop invariant motion can be very expensive, both in compilation time and  in  amount\nof  needed  compile-time memory, with very large loops.  Loops with more basic blocks\nthan this parameter won't have loop invariant motion optimization performed on them.\n\nloop-max-datarefs-for-datadeps\nBuilding data dependencies is expensive for very large loops.  This parameter  limits\nthe  number  of  data  references  in  loops  that are considered for data dependence\nanalysis.  These large loops are no handled by  the  optimizations  using  loop  data\ndependencies.\n\nmax-vartrack-size\nSets  a  maximum  number of hash table slots to use during variable tracking dataflow\nanalysis of any function.  If this  limit  is  exceeded  with  variable  tracking  at\nassignments enabled, analysis for that function is retried without it, after removing\nall  debug  insns  from  the  function.   If the limit is exceeded even without debug\ninsns, var tracking analysis is completely disabled for the  function.   Setting  the\nparameter to zero makes it unlimited.\n\nmax-vartrack-expr-depth\nSets  a  maximum  number of recursion levels when attempting to map variable names or\ndebug temporaries to value  expressions.   This  trades  compilation  time  for  more\ncomplete  debug  information.   If  this  is  set too low, value expressions that are\navailable and could be represented in debug information may end up  not  being  used;\nsetting  this  higher may enable the compiler to find more complex debug expressions,\nbut compile time and memory use may grow.\n\nmax-debug-marker-count\nSets a threshold on the number of debug markers (e.g. begin stmt  markers)  to  avoid\ncomplexity  explosion  at  inlining or expanding to RTL.  If a function has more such\ngimple stmts than the set limit, such stmts will be dropped from the inlined copy  of\na function, and from its RTL expansion.\n\nmin-nondebug-insn-uid\nUse  uids  starting  at  this  parameter  for  nondebug  insns.   The range below the\nparameter    is    reserved    exclusively    for    debug    insns    created     by\n-fvar-tracking-assignments,  but  debug insns may get (non-overlapping) uids above it\nif the reserved range is exhausted.\n\nipa-sra-deref-prob-threshold\nIPA-SRA replaces a pointer which is known not be NULL with one or more new parameters\nonly when the probability (in percent,  relative  to  function  entry)  of  it  being\ndereferenced is higher than this parameter.\n\nipa-sra-ptr-growth-factor\nIPA-SRA  replaces a pointer to an aggregate with one or more new parameters only when\ntheir cumulative size is less or equal to ipa-sra-ptr-growth-factor times the size of\nthe original pointer parameter.\n\nipa-sra-ptrwrap-growth-factor\nAdditional maximum allowed growth of  total  size  of  new  parameters  that  ipa-sra\nreplaces  a  pointer  to an aggregate with, if it points to a local variable that the\ncaller only writes to and passes it as an argument to other functions.\n\nipa-sra-max-replacements\nMaximum pieces of an aggregate that IPA-SRA tracks.  As a consequence, it is also the\nmaximum number of replacements of a formal parameter.\n\nsra-max-scalarization-size-Ospeed\nsra-max-scalarization-size-Osize\nThe two Scalar Reduction of Aggregates passes (SRA and IPA-SRA) aim to replace scalar\nparts of aggregates with uses of  independent  scalar  variables.   These  parameters\ncontrol  the  maximum  size,  in  storage units, of aggregate which is considered for\nreplacement when compiling  for  speed  (sra-max-scalarization-size-Ospeed)  or  size\n(sra-max-scalarization-size-Osize) respectively.\n\nsra-max-propagations\nThe maximum number of artificial accesses that Scalar Replacement of Aggregates (SRA)\nwill track, per one local variable, in order to facilitate copy propagation.\n\ntm-max-aggregate-size\nWhen  making  copies  of  thread-local  variables  in  a  transaction, this parameter\nspecifies the size in  bytes  after  which  variables  are  saved  with  the  logging\nfunctions  as  opposed to save/restore code sequence pairs.  This option only applies\nwhen using -fgnu-tm.\n\ngraphite-max-nb-scop-params\nTo avoid  exponential  effects  in  the  Graphite  loop  transforms,  the  number  of\nparameters  in  a Static Control Part (SCoP) is bounded.  A value of zero can be used\nto lift the bound.  A variable whose value is unknown at compilation time and defined\noutside a SCoP is a parameter of the SCoP.\n\nloop-block-tile-size\nLoop  blocking  or  strip   mining   transforms,   enabled   with   -floop-block   or\n-floop-strip-mine,  strip  mine  each  loop  in  the  loop  nest by a given number of\niterations.   The  strip  length  can  be  changed  using  the   loop-block-tile-size\nparameter.\n\nipa-jump-function-lookups\nSpecifies number of statements visited during jump function offset discovery.\n\nipa-cp-value-list-size\nIPA-CP  attempts  to  track  all  possible  values  and  types passed to a function's\nparameter in order to propagate them  and  perform  devirtualization.   ipa-cp-value-\nlist-size  is  the  maximum  number  of  values  and  types  it stores per one formal\nparameter of a function.\n\nipa-cp-eval-threshold\nIPA-CP calculates its own score of  cloning  profitability  heuristics  and  performs\nthose cloning opportunities with scores that exceed ipa-cp-eval-threshold.\n\nipa-cp-max-recursive-depth\nMaximum depth of recursive cloning for self-recursive function.\n\nipa-cp-min-recursive-probability\nRecursive  cloning  only  when  the  probability  of  call being executed exceeds the\nparameter.\n\nipa-cp-profile-count-base\nWhen using -fprofile-use option, IPA-CP will consider the measured execution count of\na call graph edge at this percentage position in their histogram as the basis for its\nheuristics calculation.\n\nipa-cp-recursive-freq-factor\nThe number of times interprocedural copy propagation expects recursive  functions  to\ncall themselves.\n\nipa-cp-recursion-penalty\nPercentage  penalty  the recursive functions will receive when they are evaluated for\ncloning.\n\nipa-cp-single-call-penalty\nPercentage penalty functions containing  a  single  call  to  another  function  will\nreceive when they are evaluated for cloning.\n\nipa-max-agg-items\nIPA-CP is also capable to propagate a number of scalar values passed in an aggregate.\nipa-max-agg-items controls the maximum number of such values per one parameter.\n\nipa-cp-loop-hint-bonus\nWhen  IPA-CP  determines that a cloning candidate would make the number of iterations\nof a loop known, it adds a bonus of ipa-cp-loop-hint-bonus to the profitability score\nof the candidate.\n\nipa-max-loop-predicates\nThe maximum number of different predicates IPA will use to describe when loops  in  a\nfunction have known properties.\n\nipa-max-aa-steps\nDuring  its  analysis  of  function bodies, IPA-CP employs alias analysis in order to\ntrack values pointed to by function parameters.  In order not  spend  too  much  time\nanalyzing  huge  functions,  it  gives  up  and  consider  all memory clobbered after\nexamining ipa-max-aa-steps statements modifying memory.\n\nipa-max-switch-predicate-bounds\nMaximal number of boundary endpoints of case ranges of switch statement.  For  switch\nexceeding this limit, IPA-CP will not construct cloning cost predicate, which is used\nto estimate cloning benefit, for default case of the switch statement.\n\nipa-max-param-expr-ops\nIPA-CP  will analyze conditional statement that references some function parameter to\nestimate benefit  for  cloning  upon  certain  constant  value.   But  if  number  of\noperations  in  a parameter expression exceeds ipa-max-param-expr-ops, the expression\nis treated as complicated one, and is not handled by IPA analysis.\n\nlto-partitions\nSpecify desired number of partitions produced during WHOPR compilation.   The  number\nof partitions should exceed the number of CPUs used for compilation.\n\nlto-min-partition\nSize  of  minimal  partition  for  WHOPR  (in estimated instructions).  This prevents\nexpenses of splitting very small programs into too many partitions.\n\nlto-max-partition\nSize of max partition for WHOPR (in estimated instructions).   to  provide  an  upper\nbound  for  individual  size  of  partition.   Meant  to  be  used only with balanced\npartitioning.\n\nlto-max-streaming-parallelism\nMaximal number of parallel processes used for LTO streaming.\n\ncxx-max-namespaces-for-diagnostic-help\nThe maximum number of namespaces to consult for  suggestions  when  C++  name  lookup\nfails for an identifier.\n\nsink-frequency-threshold\nThe  maximum  relative execution frequency (in percents) of the target block relative\nto a statement's original block to allow statement sinking of  a  statement.   Larger\nnumbers  result in more aggressive statement sinking.  A small positive adjustment is\napplied for statements with memory operands as those  are  even  more  profitable  so\nsink.\n\nmax-stores-to-sink\nThe  maximum  number of conditional store pairs that can be sunk.  Set to 0 if either\nvectorization  (-ftree-vectorize)  or   if-conversion   (-ftree-loop-if-convert)   is\ndisabled.\n\ncase-values-threshold\nThe  smallest  number  of  different  values for which it is best to use a jump-table\ninstead of a tree of conditional branches.  If the value is 0, use  the  default  for\nthe machine.\n\njump-table-max-growth-ratio-for-size\nThe  maximum  code  size  growth ratio when expanding into a jump table (in percent).\nThe parameter is used when optimizing for size.\n\njump-table-max-growth-ratio-for-speed\nThe maximum code size growth ratio when expanding into a  jump  table  (in  percent).\nThe parameter is used when optimizing for speed.\n\ntree-reassoc-width\nSet  the  maximum  number  of instructions executed in parallel in reassociated tree.\nThis parameter overrides target dependent heuristics used by default if has non  zero\nvalue.\n\nsched-pressure-algorithm\nChoose between the two available implementations of -fsched-pressure.  Algorithm 1 is\nthe original implementation and is the more likely to prevent instructions from being\nreordered.   Algorithm  2  was  designed  to  be  a compromise between the relatively\nconservative approach taken by algorithm 1 and the rather aggressive  approach  taken\nby  the  default scheduler.  It relies more heavily on having a regular register file\nand accurate register pressure classes.  See haifa-sched.cc in the  GCC  sources  for\nmore details.\n\nThe default choice depends on the target.\n\nmax-slsr-cand-scan\nSet  the  maximum  number  of  existing candidates that are considered when seeking a\nbasis for a new straight-line strength reduction candidate.\n\nasan-globals\nEnable buffer overflow detection for global objects.   This  kind  of  protection  is\nenabled  by  default  if  you are using -fsanitize=address option.  To disable global\nobjects protection use --param asan-globals=0.\n\nasan-stack\nEnable buffer overflow detection for stack  objects.   This  kind  of  protection  is\nenabled  by  default  when using -fsanitize=address.  To disable stack protection use\n--param asan-stack=0 option.\n\nasan-instrument-reads\nEnable buffer overflow detection for  memory  reads.   This  kind  of  protection  is\nenabled by default when using -fsanitize=address.  To disable memory reads protection\nuse --param asan-instrument-reads=0.\n\nasan-instrument-writes\nEnable  buffer  overflow  detection  for  memory  writes.  This kind of protection is\nenabled  by  default  when  using  -fsanitize=address.   To  disable  memory   writes\nprotection use --param asan-instrument-writes=0 option.\n\nasan-memintrin\nEnable  detection  for  built-in  functions.   This  kind of protection is enabled by\ndefault when using -fsanitize=address.  To disable built-in functions protection  use\n--param asan-memintrin=0.\n\nasan-use-after-return\nEnable  detection of use-after-return.  This kind of protection is enabled by default\nwhen  using   the   -fsanitize=address   option.    To   disable   it   use   --param\nasan-use-after-return=0.\n\nNote:   By   default  the  check  is  disabled  at  run  time.   To  enable  it,  add\n\"detectstackuseafterreturn=1\" to the environment variable ASANOPTIONS.\n\nasan-instrumentation-with-call-threshold\nIf number of memory accesses in function being instrumented is greater  or  equal  to\nthis number, use callbacks instead of inline checks.  E.g. to disable inline code use\n--param asan-instrumentation-with-call-threshold=0.\n\nasan-kernel-mem-intrinsic-prefix\nIf  nonzero,  prefix  calls  to  \"memcpy\",  \"memset\"  and  \"memmove\"  with asan or\nhwasan for -fsanitize=kernel-address or -fsanitize=kernel-hwaddress, respectively.\n\nhwasan-instrument-stack\nEnable hwasan instrumentation of statically sized  stack-allocated  variables.   This\nkind  of  instrumentation  is  enabled by default when using -fsanitize=hwaddress and\ndisabled  by  default  when  using  -fsanitize=kernel-hwaddress.   To  disable  stack\ninstrumentation  use  --param hwasan-instrument-stack=0, and to enable it use --param\nhwasan-instrument-stack=1.\n\nhwasan-random-frame-tag\nWhen  using  stack  instrumentation,  decide  tags  for  stack  variables   using   a\ndeterministic sequence beginning at a random tag for each frame.  With this parameter\nunset  tags are chosen using the same sequence but beginning from 1.  This is enabled\nby default for -fsanitize=hwaddress and unavailable for  -fsanitize=kernel-hwaddress.\nTo disable it use --param hwasan-random-frame-tag=0.\n\nhwasan-instrument-allocas\nEnable  hwasan  instrumentation of dynamically sized stack-allocated variables.  This\nkind of instrumentation is enabled by default  when  using  -fsanitize=hwaddress  and\ndisabled   by   default   when   using   -fsanitize=kernel-hwaddress.    To   disable\ninstrumentation of such variables use  --param  hwasan-instrument-allocas=0,  and  to\nenable it use --param hwasan-instrument-allocas=1.\n\nhwasan-instrument-reads\nEnable hwasan checks on memory reads.  Instrumentation of reads is enabled by default\nfor  both  -fsanitize=hwaddress and -fsanitize=kernel-hwaddress.  To disable checking\nmemory reads use --param hwasan-instrument-reads=0.\n\nhwasan-instrument-writes\nEnable hwasan checks on memory writes.   Instrumentation  of  writes  is  enabled  by\ndefault  for  both  -fsanitize=hwaddress and -fsanitize=kernel-hwaddress.  To disable\nchecking memory writes use --param hwasan-instrument-writes=0.\n\nhwasan-instrument-mem-intrinsics\nEnable hwasan instrumentation of builtin functions.  Instrumentation of these builtin\nfunctions   is   enabled   by   default    for    both    -fsanitize=hwaddress    and\n-fsanitize=kernel-hwaddress.   To  disable  instrumentation  of builtin functions use\n--param hwasan-instrument-mem-intrinsics=0.\n\nuse-after-scope-direct-emission-threshold\nIf the size of a local variable in bytes is smaller or equal to this number, directly\npoison (or unpoison) shadow memory instead of using run-time callbacks.\n\ntsan-distinguish-volatile\nEmit special instrumentation for accesses to volatiles.\n\ntsan-instrument-func-entry-exit\nEmit instrumentation calls to tsanfuncentry() and tsanfuncexit().\n\nmax-fsm-thread-path-insns\nMaximum number of instructions to copy when duplicating  blocks  on  a  finite  state\nautomaton jump thread path.\n\nthreader-debug\nthreader-debug=[none|all] Enables verbose dumping of the threader solver.\n\nparloops-chunk-size\nChunk size of omp schedule for loops parallelized by parloops.\n\nparloops-schedule\nSchedule  type  of  omp schedule for loops parallelized by parloops (static, dynamic,\nguided, auto, runtime).\n\nparloops-min-per-thread\nThe minimum number of iterations per thread of an  innermost  parallelized  loop  for\nwhich  the parallelized variant is preferred over the single threaded one.  Note that\nfor a parallelized loop nest the minimum number of iterations of the  outermost  loop\nper thread is two.\n\nmax-ssa-name-query-depth\nMaximum  depth of recursion when querying properties of SSA names in things like fold\nroutines.  One level of recursion corresponds to following a use-def chain.\n\nmax-speculative-devirt-maydefs\nThe maximum number of may-defs we analyze when looking for a must-def specifying  the\ndynamic  type of an object that invokes a virtual call we may be able to devirtualize\nspeculatively.\n\nevrp-sparse-threshold\nMaximum number of basic blocks before EVRP uses a sparse cache.\n\nranger-debug\nSpecifies the type of debug output to be issued for ranges.\n\nevrp-switch-limit\nSpecifies the maximum number of switch cases before EVRP ignores a switch.\n\nunroll-jam-min-percent\nThe minimum percentage of memory references that  must  be  optimized  away  for  the\nunroll-and-jam transformation to be considered profitable.\n\nunroll-jam-max-unroll\nThe  maximum  number of times the outer loop should be unrolled by the unroll-and-jam\ntransformation.\n\nmax-rtl-if-conversion-unpredictable-cost\nMaximum permissible cost for the sequence that would be  generated  by  the  RTL  if-\nconversion pass for a branch that is considered unpredictable.\n\nmax-variable-expansions-in-unroller\nIf  -fvariable-expansion-in-unroller  is  used,  the  maximum number of times that an\nindividual variable will be expanded during loop unrolling.\n\npartial-inlining-entry-probability\nMaximum probability of the entry BB of split region (in percent relative to entry  BB\nof the function) to make partial inlining happen.\n\nmax-tracked-strlens\nMaximum  number  of  strings  for  which  strlen  optimization pass will track string\nlengths.\n\ngcse-after-reload-partial-fraction\nThe threshold ratio for performing partial redundancy elimination after reload.\n\ngcse-after-reload-critical-fraction\nThe threshold  ratio  of  critical  edges  execution  count  that  permit  performing\nredundancy elimination after reload.\n\nmax-loop-header-insns\nThe maximum number of insns in loop header duplicated by the copy loop headers pass.\n\nvect-epilogues-nomask\nEnable loop epilogue vectorization using smaller vector size.\n\nvect-partial-vector-usage\nControls  when the loop vectorizer considers using partial vector loads and stores as\nan alternative to falling back to scalar code.  0  stops  the  vectorizer  from  ever\nusing  partial  vector loads and stores.  1 allows partial vector loads and stores if\nvectorization removes the need for the code to  iterate.   2  allows  partial  vector\nloads  and  stores  in  all  loops.  The parameter only has an effect on targets that\nsupport partial vector loads and stores.\n\nvect-inner-loop-cost-factor\nThe maximum factor which the loop vectorizer applies to the cost of statements in  an\ninner  loop relative to the loop being vectorized.  The factor applied is the maximum\nof the estimated number of iterations of the inner  loop  and  this  parameter.   The\ndefault value of this parameter is 50.\n\nvect-induction-float\nEnable loop vectorization of floating point inductions.\n\navoid-fma-max-bits\nMaximum number of bits for which we avoid creating FMAs.\n\nsms-loop-average-count-threshold\nA threshold on the average loop count considered by the swing modulo scheduler.\n\nsms-dfa-history\nThe  number  of  cycles  the swing modulo scheduler considers when checking conflicts\nusing DFA.\n\ngraphite-allow-codegen-errors\nWhether codegen errors should be ICEs when -fchecking.\n\nsms-max-ii-factor\nA factor for tuning the upper bound that swing modulo scheduler uses for scheduling a\nloop.\n\nlra-max-considered-reload-pseudos\nThe max number of reload pseudos which are considered during  spilling  a  non-reload\npseudo.\n\nmax-pow-sqrt-depth\nMaximum  depth  of  sqrt  chains  to  use  when synthesizing exponentiation by a real\nconstant.\n\nmax-dse-active-local-stores\nMaximum number of active local stores in RTL dead store elimination.\n\nasan-instrument-allocas\nEnable asan allocas/VLAs protection.\n\nmax-iterations-computation-cost\nBound on the cost of an expression to compute the number of iterations.\n\nmax-isl-operations\nMaximum number of isl operations, 0 means unlimited.\n\ngraphite-max-arrays-per-scop\nMaximum number of arrays per scop.\n\nmax-vartrack-reverse-op-size\nMax. size of loc list for which reverse ops should be added.\n\nfsm-scale-path-stmts\nScale factor to apply to the number of statements in a threading path crossing a loop\nbackedge when comparing to --param=max-jump-thread-duplication-stmts.\n\nuninit-control-dep-attempts\nMaximum  number  of  nested  calls  to  search  for   control   dependencies   during\nuninitialized variable analysis.\n\nuninit-max-chain-len\nMaximum  number  of  predicates  anded  for  each  predicate  ored  in the normalized\npredicate chain.\n\nuninit-max-num-chains\nMaximum number of predicates ored in the normalized predicate chain.\n\nsched-autopref-queue-depth\nHardware autoprefetcher scheduler model control flag.  Number of lookahead cycles the\nmodel looks into; at ' ' only enable instruction sorting heuristic.\n\nloop-versioning-max-inner-insns\nThe maximum number of instructions that an  inner  loop  can  have  before  the  loop\nversioning pass considers it too big to copy.\n\nloop-versioning-max-outer-insns\nThe  maximum  number  of  instructions  that  an  outer loop can have before the loop\nversioning pass considers it too big to copy, discounting any instructions  in  inner\nloops that directly benefit from versioning.\n\nssa-name-def-chain-limit\nThe  maximum  number of SSANAME assignments to follow in determining a property of a\nvariable such as its value.  This limits the number of iterations or recursive  calls\nGCC  performs  when  optimizing certain statements or when determining their validity\nprior to issuing diagnostics.\n\nstore-merging-max-size\nMaximum size of a single store merging region in bytes.\n\nhash-table-verification-limit\nThe number of elements for which hash table verification is done  for  each  searched\nelement.\n\nmax-find-base-term-values\nMaximum number of VALUEs handled during a single findbaseterm call.\n\nanalyzer-max-enodes-per-program-point\nThe  maximum  number  of exploded nodes per program point within the analyzer, before\nterminating analysis of that point.\n\nanalyzer-max-constraints\nThe maximum number of constraints per state.\n\nanalyzer-min-snodes-for-call-summary\nThe minimum number of supernodes within a  function  for  the  analyzer  to  consider\nsummarizing its effects at call sites.\n\nanalyzer-max-enodes-for-full-dump\nThe maximum depth of exploded nodes that should appear in a dot dump before switching\nto a less verbose format.\n\nanalyzer-max-recursion-depth\nThe  maximum  number  of  times  a  callsite  can  appear  in a call stack within the\nanalyzer, before terminating analysis of a call that would recurse deeper.\n\nanalyzer-max-svalue-depth\nThe maximum depth of a symbolic value, before approximating the value as unknown.\n\nanalyzer-max-infeasible-edges\nThe maximum number of infeasible edges to reject before  declaring  a  diagnostic  as\ninfeasible.\n\ngimple-fe-computed-hot-bb-threshold\nThe  number of executions of a basic block which is considered hot.  The parameter is\nused only in GIMPLE FE.\n\nanalyzer-bb-explosion-factor\nThe maximum number of 'after  supernode'  exploded  nodes  within  the  analyzer  per\nsupernode, before terminating analysis.\n\nranger-logical-depth\nMaximum  depth  of  logical  expression  evaluation  ranger  will  look  through when\nevaluating outgoing edge ranges.\n\nranger-recompute-depth\nMaximum depth of instruction chains to consider for  recomputation  in  the  outgoing\nrange calculator.\n\nrelation-block-limit\nMaximum number of relations the oracle will register in a basic block.\n\nmin-pagesize\nMinimum page size for warning purposes.\n\nopenacc-kernels\nSpecify     mode     of     OpenACC     `kernels'    constructs    handling.     With\n--param=openacc-kernels=decompose, OpenACC `kernels' constructs are  decomposed  into\nparts,  a  sequence  of  compute constructs, each then handled individually.  This is\nwork  in  progress.    With   --param=openacc-kernels=parloops,   OpenACC   `kernels'\nconstructs are handled by the parloops pass, en bloc.  This is the current default.\n\nopenacc-privatization\nControl  whether the -fopt-info-omp-note and applicable -fdump-tree-*-details options\nemit OpenACC privatization  diagnostics.   With  --param=openacc-privatization=quiet,\ndon't      diagnose.       This      is      the      current      default.      With\n--param=openacc-privatization=noisy, do diagnose.\n\nThe following choices of name are available on AArch64 targets:\n\naarch64-sve-compare-costs\nWhen vectorizing for SVE, consider using \"unpacked\" vectors for smaller elements  and\nuse  the cost model to pick the cheapest approach.  Also use the cost model to choose\nbetween SVE and Advanced SIMD vectorization.\n\nUsing unpacked vectors includes storing smaller elements  in  larger  containers  and\naccessing elements with extending loads and truncating stores.\n\naarch64-float-recp-precision\nThe  number  of Newton iterations for calculating the reciprocal for float type.  The\nprecision of division is proportional to this param when  division  approximation  is\nenabled.  The default value is 1.\n\naarch64-double-recp-precision\nThe  number of Newton iterations for calculating the reciprocal for double type.  The\nprecision of division is propotional to this param  when  division  approximation  is\nenabled.  The default value is 2.\n\naarch64-autovec-preference\nForce  an ISA selection strategy for auto-vectorization.  Accepts values from 0 to 4,\ninclusive.\n\n0   Use the default heuristics.\n\n1   Use only Advanced SIMD for auto-vectorization.\n\n2   Use only SVE for auto-vectorization.\n\n3   Use both Advanced SIMD and SVE.  Prefer Advanced SIMD when the costs  are  deemed\nequal.\n\n4   Use both Advanced SIMD and SVE.  Prefer SVE when the costs are deemed equal.\n\nThe default value is 0.\n\naarch64-loop-vect-issue-rate-niters\nThe  tuning  for  some AArch64 CPUs tries to take both latencies and issue rates into\naccount when deciding whether a loop should be vectorized using SVE, vectorized using\nAdvanced SIMD, or not vectorized at all.  If this parameter is set to n, GCC will not\nuse this heuristic for loops that are known to execute in fewer than n Advanced  SIMD\niterations.\n\naarch64-vect-unroll-limit\nThe vectorizer will use available tuning information to determine whether it would be\nbeneficial  to unroll the main vectorized loop and by how much.  This parameter set's\nthe upper bound of how much the vectorizer will unroll the main  loop.   The  default\nvalue is four.\n\nThe following choices of name are available on i386 and x8664 targets:\n\nx86-stlf-window-ninsns\nInstructions number above which STFL stall penalty can be compensated.\n\nx86-stv-max-visits\nThe  maximum  number  of  use  and def visits when discovering a STV chain before the\ndiscovery is aborted.\n"
                },
                {
                    "name": "Program Instrumentation Options",
                    "content": "GCC supports a number of command-line options that control adding run-time instrumentation to\nthe code it normally generates.  For example,  one  purpose  of  instrumentation  is  collect\nprofiling  statistics  for  use  in  finding  program  hot  spots, code coverage analysis, or\nprofile-guided optimizations.  Another class of program instrumentation  is  adding  run-time\nchecking  to  detect  programming  errors  like invalid pointer dereferences or out-of-bounds\narray accesses, as well as deliberately hostile attacks such as stack smashing or C++  vtable\nhijacking.   There  is  also  a  general  hook  which can be used to implement other forms of\ntracing or function-level instrumentation for debug or program analysis purposes.\n"
                },
                {
                    "name": "-p",
                    "content": "",
                    "flag": "-p"
                },
                {
                    "name": "-pg",
                    "content": "(for  -p)  or  gprof (for -pg).  You must use this option when compiling the source files\nyou want data about, and you must also use it when linking.\n\nYou can use the function attribute  \"noinstrumentfunction\"  to  suppress  profiling  of\nindividual functions when compiling with these options.\n"
                },
                {
                    "name": "-fprofile-arcs",
                    "content": "Add  code  so  that  program  flow  arcs  are instrumented.  During execution the program\nrecords how many times each branch and call is executed and how many times it is taken or\nreturns.  On targets that support constructors with priority support, profiling  properly\nhandles constructors, destructors and C++ constructors (and destructors) of classes which\nare used as a type of a global variable.\n\nWhen the compiled program exits it saves this data to a file called auxname.gcda for each\nsource    file.     The   data   may   be   used   for   profile-directed   optimizations\n(-fbranch-probabilities), or for test coverage analysis (-ftest-coverage).   Each  object\nfile's auxname is generated from the name of the output file, if explicitly specified and\nit is not the final executable, otherwise it is the basename of the source file.  In both\ncases  any suffix is removed (e.g. foo.gcda for input file dir/foo.c, or dir/foo.gcda for\noutput file specified as -o dir/foo.o).\n\nNote that if a command line directly links source files, the  corresponding  .gcda  files\nwill  be  prefixed  with  the  unsuffixed  name of the output file.  E.g. \"gcc a.c b.c -o\nbinary\" would generate binary-a.gcda and binary-b.gcda files.\n"
                },
                {
                    "name": "--coverage",
                    "content": "This option is used to compile and link code instrumented  for  coverage  analysis.   The\noption  is a synonym for -fprofile-arcs -ftest-coverage (when compiling) and -lgcov (when\nlinking).  See the documentation for those options for more details.\n\n*   Compile the source files with -fprofile-arcs plus optimization  and  code  generation\noptions.  For test coverage analysis, use the additional -ftest-coverage option.  You\ndo not need to profile every source file in a program.\n\n*   Compile the source files additionally with -fprofile-abs-path to create absolute path\nnames  in  the .gcno files.  This allows gcov to find the correct sources in projects\nwhere compilations occur with different working directories.\n\n*   Link your object files with -lgcov or -fprofile-arcs (the latter implies the former).\n\n*   Run the program on a representative workload to generate the arc profile information.\nThis may be repeated any number of times.  You can run concurrent instances  of  your\nprogram,  and  provided that the file system supports locking, the data files will be\ncorrectly updated.  Unless a strict ISO C dialect option is in effect,  \"fork\"  calls\nare detected and correctly handled without double counting.\n\nMoreover, an object file can be recompiled multiple times and the corresponding .gcda\nfile merges as long as the source file and the compiler options are unchanged.\n\n*   For  profile-directed  optimizations,  compile  the  source files again with the same\noptimization and code generation options plus -fbranch-probabilities.\n\n*   For test coverage analysis, use gcov to produce human readable information  from  the\n.gcno and .gcda files.  Refer to the gcov documentation for further information.\n\nWith  -fprofile-arcs, for each function of your program GCC creates a program flow graph,\nthen finds a spanning tree for the graph.  Only arcs that are not on  the  spanning  tree\nhave  to  be instrumented: the compiler adds code to count the number of times that these\narcs are executed.  When an arc is the only  exit  or  only  entrance  to  a  block,  the\ninstrumentation  code  can  be  added  to the block; otherwise, a new basic block must be\ncreated to hold the instrumentation code.\n",
                    "long": "--coverage"
                },
                {
                    "name": "-ftest-coverage",
                    "content": "Produce a notes file that  the  gcov  code-coverage  utility  can  use  to  show  program\ncoverage.    Each  source  file's  note  file  is  called  auxname.gcno.   Refer  to  the\n-fprofile-arcs option above for a description of  auxname  and  instructions  on  how  to\ngenerate  test coverage data.  Coverage data matches the source files more closely if you\ndo not optimize.\n"
                },
                {
                    "name": "-fprofile-abs-path",
                    "content": "Automatically convert relative source file names to absolute  path  names  in  the  .gcno\nfiles.  This allows gcov to find the correct sources in projects where compilations occur\nwith different working directories.\n"
                },
                {
                    "name": "-fprofile-dir=_",
                    "content": "Set  the  directory to search for the profile data files in to path.  This option affects\nonly the profile data generated by  -fprofile-generate,  -ftest-coverage,  -fprofile-arcs\nand  used  by  -fprofile-use  and  -fbranch-probabilities  and its related options.  Both\nabsolute and relative paths can be used.  By default, GCC uses the current  directory  as\npath,  thus  the  profile data file appears in the same directory as the object file.  In\norder to prevent the file name clashing, if the object file name is not an absolute path,\nwe mangle the absolute path of the sourcename.gcda file and use it as the file name of  a\n.gcda  file.   See  details  about the file naming in -fprofile-arcs.  See similar option\n-fprofile-note.\n\nWhen an executable is run in a massive parallel environment, it is  recommended  to  save\nprofile  to different folders.  That can be done with variables in path that are exported\nduring run-time:\n\n%p  process ID.\n\n%q{VAR}\nvalue of environment variable VAR\n"
                },
                {
                    "name": "-fprofile-generate",
                    "content": ""
                },
                {
                    "name": "-fprofile-generate=_",
                    "content": "Enable options usually used for instrumenting application to produce profile  useful  for\nlater   recompilation   with   profile   feedback   based  optimization.   You  must  use\n-fprofile-generate both when compiling and when linking your program.\n\nThe following options are enabled: -fprofile-arcs, -fprofile-values,  -finline-functions,\nand -fipa-bit-cp.\n\nIf  path is specified, GCC looks at the path to find the profile feedback data files. See\n-fprofile-dir.\n\nTo optimize the program based on the collected profile information, use -fprofile-use.\n"
                },
                {
                    "name": "-fprofile-info-section",
                    "content": ""
                },
                {
                    "name": "-fprofile-info-section=_",
                    "content": "Register  the  profile  information  in  the  specified  section  instead  of   using   a\nconstructor/destructor.   The  section  name  is  name  if it is specified, otherwise the\nsection name defaults to \".gcovinfo\".  A pointer to the profile information generated by\n-fprofile-arcs is placed in the specified section for each translation unit.  This option\ndisables the profile information registration through a constructor and it  disables  the\nprofile  information  processing through a destructor.  This option is not intended to be\nused in hosted environments such as GNU/Linux.  It targets freestanding environments (for\nexample   embedded   systems)   with   limited   resources   which   do    not    support\nconstructors/destructors or the C library file I/O.\n\nThe linker could collect the input sections in a continuous memory block and define start\nand  end  symbols.   A  GNU  linker  script example which defines a linker output section\nfollows:\n\n.gcovinfo      :\n{\nPROVIDE (gcovinfostart = .);\nKEEP (*(.gcovinfo))\nPROVIDE (gcovinfoend = .);\n}\n\nThe program could dump the profiling  information  registered  in  this  linker  set  for\nexample like this:\n\n#include <gcov.h>\n#include <stdio.h>\n#include <stdlib.h>\n\nextern const struct gcovinfo *const gcovinfostart[];\nextern const struct gcovinfo *const gcovinfoend[];\n\nstatic void\ndump (const void *d, unsigned n, void *arg)\n{\nconst unsigned char *c = d;\n\nfor (unsigned i = 0; i < n; ++i)\nprintf (\"%02x\", c[i]);\n}\n\nstatic void\nfilename (const char *f, void *arg)\n{\ngcovfilenametogcfn (f, dump, arg );\n}\n\nstatic void *\nallocate (unsigned length, void *arg)\n{\nreturn malloc (length);\n}\n\nstatic void\ndumpgcovinfo (void)\n{\nconst struct gcovinfo *const *info = gcovinfostart;\nconst struct gcovinfo *const *end = gcovinfoend;\n\n/* Obfuscate variable to prevent compiler optimizations.  */\nasm (\"\" : \"+r\" (info));\n\nwhile (info != end)\n{\nvoid *arg = NULL;\ngcovinfotogcda (*info, filename, dump, allocate, arg);\nputchar ('\\n');\n++info;\n}\n}\n\nint\nmain (void)\n{\ndumpgcovinfo ();\nreturn 0;\n}\n\nThe  merge-stream  subcommand  of  gcov-tool  may  be used to deserialize the data stream\ngenerated by the \"gcovfilenametogcfn\" and \"gcovinfotogcda\" functions and  merge\nthe profile information into .gcda files on the host filesystem.\n"
                },
                {
                    "name": "-fprofile-note=_",
                    "content": "If path is specified, GCC saves .gcno file into path location.  If you combine the option\nwith multiple source files, the .gcno file will be overwritten.\n"
                },
                {
                    "name": "-fprofile-prefix-path=_",
                    "content": "This   option   can   be   used  in  combination  with  profile-generate=profiledir  and\nprofile-use=profiledir to inform GCC where is the base directory of built  source  tree.\nBy default profiledir will contain files with mangled absolute paths of all object files\nin  the  built  project.   This  is  not  desirable  when  directory  used  to  build the\ninstrumented binary differs from the directory used to build the  binary  optimized  with\nprofile  feedback  because the profile data will not be found during the optimized build.\nIn such setups -fprofile-prefix-path=path with path pointing to the base directory of the\nbuild can be used to strip the irrelevant part of  the  path  and  keep  all  file  names\nrelative to the main build directory.\n"
                },
                {
                    "name": "-fprofile-prefix-map=_",
                    "content": "When  compiling  files  residing  in  directory  old,  record profiling information (with\n--coverage) describing them as if the files resided in directory new instead.   See  also\n-ffile-prefix-map and -fcanon-prefix-map.\n"
                },
                {
                    "name": "-fprofile-update=_",
                    "content": "Alter  the  update  method  for  an  application  instrumented for profile feedback based\noptimization.  The method argument should be one of single, atomic or prefer-atomic.  The\nfirst one is useful for single-threaded  applications,  while  the  second  one  prevents\nprofile corruption by emitting thread-safe code.\n\nWarning:  When  an application does not properly join all threads (or creates an detached\nthread), a profile file can be still corrupted.\n\nUsing prefer-atomic would be transformed either to atomic, when supported by a target, or\nto single otherwise.  The GCC driver automatically selects prefer-atomic when -pthread is\npresent in the command line.\n"
                },
                {
                    "name": "-fprofile-filter-files=_",
                    "content": "Instrument only functions from files whose name matches any of  the  regular  expressions\n(separated by semi-colons).\n\nFor  example,  -fprofile-filter-files=main\\.c;module.*\\.c will instrument only main.c and\nall C files starting with 'module'.\n"
                },
                {
                    "name": "-fprofile-exclude-files=_",
                    "content": "Instrument only functions from files whose  name  does  not  match  any  of  the  regular\nexpressions (separated by semi-colons).\n\nFor  example,  -fprofile-exclude-files=/usr/.*  will prevent instrumentation of all files\nthat are located in the /usr/ folder.\n"
                },
                {
                    "name": "-fprofile-reproducible=",
                    "content": "Control level of reproducibility of profile gathered by \"-fprofile-generate\".  This makes\nit possible to rebuild program with same  outcome  which  is  useful,  for  example,  for\ndistribution packages.\n\nWith   -fprofile-reproducible=serial   the  profile  gathered  by  -fprofile-generate  is\nreproducible provided the trained program behaves the same  at  each  invocation  of  the\ntrain run, it is not multi-threaded and profile data streaming is always done in the same\norder.   Note  that  profile  streaming happens at the end of program run but also before\n\"fork\" function is invoked.\n\nNote that it is quite common that execution counts of some part of programs depends,  for\nexample, on length of temporary file names or memory space randomization (that may affect\nhash-table  collision  rate).  Such non-reproducible part of programs may be annotated by\n\"noinstrumentfunction\" function attribute. gcov-dump  with  -l  can  be  used  to  dump\ngathered data and verify that they are indeed reproducible.\n\nWith -fprofile-reproducible=parallel-runs collected profile stays reproducible regardless\nthe  order  of  streaming of the data into gcda files.  This setting makes it possible to\nrun multiple instances of instrumented program in parallel (such as with \"make -j\"). This\nreduces quality of gathered data, in particular of indirect call profiling.\n"
                },
                {
                    "name": "-fsanitize=address",
                    "content": "Enable AddressSanitizer, a fast memory error detector.  Memory  access  instructions  are\ninstrumented  to  detect  out-of-bounds  and  use-after-free  bugs.   The  option enables\n-fsanitize-address-use-after-scope.                                                   See\n<https://github.com/google/sanitizers/wiki/AddressSanitizer>  for more details.  The run-\ntime behavior can be influenced using the ASANOPTIONS environment variable.  When set to\n\"help=1\", the available options are shown at startup of the  instrumented  program.   See\n<https://github.com/google/sanitizers/wiki/AddressSanitizerFlags#run-time-flags>   for  a\nlist of supported options.  The option  cannot  be  combined  with  -fsanitize=thread  or\n-fsanitize=hwaddress.   Note  that  the  only  target  -fsanitize=hwaddress  is currently\nsupported on is AArch64.\n\nTo get more accurate stack traces, it is possible to use options such as -O0, -O1, or -Og\n(which, for instance, prevent most function inlining), -fno-optimize-sibling-calls (which\nprevents optimizing sibling and tail recursive calls; this option is  implicit  for  -O0,\n-O1,  or  -Og),  or  -fno-ipa-icf  (which disables Identical Code Folding for functions).\nSince multiple runs of the program may yield backtraces with different addresses  due  to\nASLR  (Address  Space  Layout  Randomization),  it may be desirable to turn ASLR off.  On\nLinux, this can be achieved with setarch `uname -m` -R ./prog.\n"
                },
                {
                    "name": "-fsanitize=kernel-address",
                    "content": "Enable         AddressSanitizer         for          Linux          kernel.           See\n<https://github.com/google/kernel-sanitizers> for more details.\n"
                },
                {
                    "name": "-fsanitize=hwaddress",
                    "content": "Enable  Hardware-assisted  AddressSanitizer,  which uses a hardware ability to ignore the\ntop byte of a pointer to allow the detection of memory errors with a low memory overhead.\nMemory access instructions are instrumented to detect  out-of-bounds  and  use-after-free\nbugs.       The      option      enables     -fsanitize-address-use-after-scope.      See\n<https://clang.llvm.org/docs/HardwareAssistedAddressSanitizerDesign.html>    for     more\ndetails.   The  run-time  behavior can be influenced using the HWASANOPTIONS environment\nvariable.  When set to \"help=1\", the available  options  are  shown  at  startup  of  the\ninstrumented   program.    The  option  cannot  be  combined  with  -fsanitize=thread  or\n-fsanitize=address, and is currently only available on AArch64.\n"
                },
                {
                    "name": "-fsanitize=kernel-hwaddress",
                    "content": "Enable Hardware-assisted AddressSanitizer for compilation of the Linux  kernel.   Similar\nto  -fsanitize=kernel-address  but using an alternate instrumentation method, and similar\nto -fsanitize=hwaddress but with instrumentation differences necessary for compiling  the\nLinux  kernel.  These differences are to avoid hwasan library initialization calls and to\naccount for the stack pointer having a different value in its top byte.\n\nNote: This option has different defaults to the -fsanitize=hwaddress.  Instrumenting  the\nstack  and  alloca  calls  are not on by default but are still possible by specifying the\ncommand-line     options     --param      hwasan-instrument-stack=1      and      --param\nhwasan-instrument-allocas=1 respectively. Using a random frame tag is not implemented for\nkernel instrumentation.\n"
                },
                {
                    "name": "-fsanitize=pointer-compare",
                    "content": "Instrument comparison operation (<, <=, >, >=) with pointer operands.  The option must be\ncombined with either -fsanitize=kernel-address or -fsanitize=address The option cannot be\ncombined with -fsanitize=thread.  Note: By default the check is disabled at run time.  To\nenable it, add \"detectinvalidpointerpairs=2\" to the environment variable ASANOPTIONS.\nUsing  \"detectinvalidpointerpairs=1\" detects invalid operation only when both pointers\nare non-null.\n"
                },
                {
                    "name": "-fsanitize=pointer-subtract",
                    "content": "Instrument subtraction with pointer operands.  The option must be  combined  with  either\n-fsanitize=kernel-address  or  -fsanitize=address  The  option  cannot  be  combined with\n-fsanitize=thread.  Note: By default the check is disabled at run time.   To  enable  it,\nadd  \"detectinvalidpointerpairs=2\"  to  the  environment  variable ASANOPTIONS. Using\n\"detectinvalidpointerpairs=1\" detects invalid operation only when  both  pointers  are\nnon-null.\n"
                },
                {
                    "name": "-fsanitize=shadow-call-stack",
                    "content": "Enable ShadowCallStack, a security enhancement mechanism used to protect programs against\nreturn address overwrites (e.g. stack buffer overflows.)  It works by saving a function's\nreturn  address  to a separately allocated shadow call stack in the function prologue and\nrestoring the return address from  the  shadow  call  stack  in  the  function  epilogue.\nInstrumentation  only  occurs  in  functions  that need to save the return address to the\nstack.\n\nCurrently it only supports the aarch64 platform.  It is specifically designed  for  linux\nkernels  that  enable  the CONFIGSHADOWCALLSTACK option.  For the user space programs,\nruntime support is not currently provided in libc and libgcc.  Users who want to use this\nfeature in user space need to provide their own support for the runtime.   It  should  be\nnoted that this may cause the ABI rules to be broken.\n\nOn aarch64, the instrumentation makes use of the platform register \"x18\".  This generally\nmeans that any code that may run on the same thread as code compiled with ShadowCallStack\nmust  be  compiled  with  the  flag  -ffixed-x18,  otherwise  functions  compiled without\n-ffixed-x18 might clobber \"x18\" and so corrupt the shadow stack pointer.\n\nAlso, because there is no userspace runtime support, code compiled  with  ShadowCallStack\ncannot use exception handling.  Use -fno-exceptions to turn off exceptions.\n\nSee <https://clang.llvm.org/docs/ShadowCallStack.html> for more details.\n"
                },
                {
                    "name": "-fsanitize=thread",
                    "content": "Enable  ThreadSanitizer,  a  fast  data  race  detector.   Memory access instructions are\ninstrumented        to        detect         data         race         bugs.          See\n<https://github.com/google/sanitizers/wiki#threadsanitizer>  for  more  details. The run-\ntime behavior  can  be  influenced  using  the  TSANOPTIONS  environment  variable;  see\n<https://github.com/google/sanitizers/wiki/ThreadSanitizerFlags>  for a list of supported\noptions.  The option cannot be combined with -fsanitize=address, -fsanitize=leak.\n\nNote that sanitized atomic builtins cannot throw exceptions  when  operating  on  invalid\nmemory addresses with non-call exceptions (-fnon-call-exceptions).\n"
                },
                {
                    "name": "-fsanitize=leak",
                    "content": "Enable  LeakSanitizer,  a  memory leak detector.  This option only matters for linking of\nexecutables.  The executable is linked against a  library  that  overrides  \"malloc\"  and\nother                     allocator                    functions.                     See\n<https://github.com/google/sanitizers/wiki/AddressSanitizerLeakSanitizer>    for     more\ndetails.   The  run-time  behavior  can  be influenced using the LSANOPTIONS environment\nvariable.  The option cannot be combined with -fsanitize=thread.\n"
                },
                {
                    "name": "-fsanitize=undefined",
                    "content": "Enable  UndefinedBehaviorSanitizer,  a  fast  undefined   behavior   detector.    Various\ncomputations   are   instrumented   to   detect   undefined  behavior  at  runtime.   See\n<https://clang.llvm.org/docs/UndefinedBehaviorSanitizer.html>  for  more  details.    The\nrun-time  behavior  can  be  influenced  using  the  UBSANOPTIONS  environment variable.\nCurrent suboptions are:\n\n-fsanitize=shift\nThis option enables checking that the result of a shift operation is  not  undefined.\nNote that what exactly is considered undefined differs slightly between C and C++, as\nwell   as   between   ISO  C90  and  C99,  etc.   This  option  has  two  suboptions,\n-fsanitize=shift-base and -fsanitize=shift-exponent.\n\n-fsanitize=shift-exponent\nThis option enables checking that the second argument of a  shift  operation  is  not\nnegative and is smaller than the precision of the promoted first argument.\n\n-fsanitize=shift-base\nIf the second argument of a shift operation is within range, check that the result of\na  shift  operation is not undefined.  Note that what exactly is considered undefined\ndiffers slightly between C and C++, as well as between ISO C90 and C99, etc.\n\n-fsanitize=integer-divide-by-zero\nDetect integer division by zero.\n\n-fsanitize=unreachable\nWith this  option,  the  compiler  turns  the  \"builtinunreachable\"  call  into  a\ndiagnostics  message  call  instead.  When reaching the \"builtinunreachable\" call,\nthe behavior is undefined.\n\n-fsanitize=vla-bound\nThis option instructs the compiler to check that the size of a variable length  array\nis positive.\n\n-fsanitize=null\nThis  option enables pointer checking.  Particularly, the application built with this\noption turned on will issue an error message when it  tries  to  dereference  a  NULL\npointer, or if a reference (possibly an rvalue reference) is bound to a NULL pointer,\nor if a method is invoked on an object pointed by a NULL pointer.\n\n-fsanitize=return\nThis  option  enables  return  statement  checking.   Programs built with this option\nturned on will issue an error message when the end of a non-void function is  reached\nwithout actually returning a value.  This option works in C++ only.\n\n-fsanitize=signed-integer-overflow\nThis  option  enables  signed integer overflow checking.  We check that the result of\n\"+\", \"*\", and both unary and binary \"-\" does not overflow in the signed  arithmetics.\nThis also detects \"INTMIN / -1\" signed division.  Note, integer promotion rules must\nbe taken into account.  That is, the following is not an overflow:\n\nsigned char a = SCHARMAX;\na++;\n\n-fsanitize=bounds\nThis  option enables instrumentation of array bounds.  Various out of bounds accesses\nare detected.   Flexible  array  members,  flexible  array  member-like  arrays,  and\ninitializers  of  variables  with  static  storage  are  not  instrumented,  with the\nexception of flexible array member-like arrays for  which  \"-fstrict-flex-arrays\"  or\n\"-fstrict-flex-arrays=\"  options or \"strictflexarray\" attributes say they shouldn't\nbe treated like flexible array member-like arrays.\n\n-fsanitize=bounds-strict\nThis option enables strict instrumentation of  array  bounds.   Most  out  of  bounds\naccesses  are detected, including flexible array member-like arrays.  Initializers of\nvariables with static storage are not instrumented.\n\n-fsanitize=alignment\nThis option enables checking of alignment of pointers when they are dereferenced,  or\nwhen  a  reference  is  bound  to  insufficiently aligned target, or when a method or\nconstructor is invoked on insufficiently aligned object.\n\n-fsanitize=object-size\nThis   option   enables   instrumentation   of   memory    references    using    the\n\"builtindynamicobjectsize\" function.  Various out of bounds pointer accesses are\ndetected.\n\n-fsanitize=float-divide-by-zero\nDetect   floating-point   division   by   zero.    Unlike   other   similar  options,\n-fsanitize=float-divide-by-zero  is  not  enabled  by   -fsanitize=undefined,   since\nfloating-point  division  by zero can be a legitimate way of obtaining infinities and\nNaNs.\n\n-fsanitize=float-cast-overflow\nThis option enables floating-point type to integer  conversion  checking.   We  check\nthat  the  result of the conversion does not overflow.  Unlike other similar options,\n-fsanitize=float-cast-overflow is not enabled by -fsanitize=undefined.   This  option\ndoes not work well with \"FEINVALID\" exceptions enabled.\n\n-fsanitize=nonnull-attribute\nThis  option  enables  instrumentation of calls, checking whether null values are not\npassed to arguments marked as requiring a non-null value by  the  \"nonnull\"  function\nattribute.\n\n-fsanitize=returns-nonnull-attribute\nThis  option  enables  instrumentation  of return statements in functions marked with\n\"returnsnonnull\" function attribute, to detect returning of null  values  from  such\nfunctions.\n\n-fsanitize=bool\nThis option enables instrumentation of loads from bool.  If a value other than 0/1 is\nloaded, a run-time error is issued.\n\n-fsanitize=enum\nThis  option  enables instrumentation of loads from an enum type.  If a value outside\nthe range of values for the enum type is loaded, a run-time error is issued.\n\n-fsanitize=vptr\nThis option enables instrumentation of C++ member function calls, member accesses and\nsome conversions between  pointers  to  base  and  derived  classes,  to  verify  the\nreferenced object has the correct dynamic type.\n\n-fsanitize=pointer-overflow\nThis   option  enables  instrumentation  of  pointer  arithmetics.   If  the  pointer\narithmetics overflows, a run-time error is issued.\n\n-fsanitize=builtin\nThis option enables instrumentation of arguments to selected builtin  functions.   If\nan  invalid  value  is  passed  to  such arguments, a run-time error is issued.  E.g.\npassing 0 as the argument to \"builtinctz\"  or  \"builtinclz\"  invokes  undefined\nbehavior and is diagnosed by this option.\n\nNote  that  sanitizers tend to increase the rate of false positive warnings, most notably\nthose around -Wmaybe-uninitialized.  We recommend against combining -Werror and [the  use\nof] sanitizers.\n\nWhile -ftrapv causes traps for signed overflows to be emitted, -fsanitize=undefined gives\na diagnostic message.  This currently works only for the C family of languages.\n"
                },
                {
                    "name": "-fno-sanitize=all",
                    "content": "This  option  disables all previously enabled sanitizers.  -fsanitize=all is not allowed,\nas some sanitizers cannot be used together.\n"
                },
                {
                    "name": "-fasan-shadow-offset=_",
                    "content": "This option forces GCC to use custom shadow offset in  AddressSanitizer  checks.   It  is\nuseful for experimenting with different shadow memory layouts in Kernel AddressSanitizer.\n"
                },
                {
                    "name": "-fsanitize-sections=_",
                    "content": "Sanitize global variables in selected user-defined sections.  si may contain wildcards.\n"
                },
                {
                    "name": "-fsanitize-recover",
                    "content": "-fsanitize-recover=  controls  error  recovery  mode  for  sanitizers mentioned in comma-\nseparated list of opts.  Enabling this option for a  sanitizer  component  causes  it  to\nattempt  to  continue  running  the program as if no error happened.  This means multiple\nruntime errors can be reported in a single program run, and the exit code of the  program\nmay  indicate  success  even  when errors have been reported.  The -fno-sanitize-recover=\noption can be used to alter this behavior: only the first detected error is reported  and\nprogram then exits with a non-zero exit code.\n\nCurrently this feature only works for -fsanitize=undefined (and its suboptions except for\n-fsanitize=unreachable     and     -fsanitize=return),    -fsanitize=float-cast-overflow,\n-fsanitize=float-divide-by-zero, -fsanitize=bounds-strict, -fsanitize=kernel-address  and\n-fsanitize=address.   For these sanitizers error recovery is turned on by default, except\n-fsanitize=address, for which this feature is experimental.   -fsanitize-recover=all  and\n-fno-sanitize-recover=all   is  also  accepted,  the  former  enables  recovery  for  all\nsanitizers that support it, the latter disables recovery for all sanitizers that  support\nit.\n\nEven  if  a  recovery mode is turned on the compiler side, it needs to be also enabled on\nthe runtime library side, otherwise the failures are still fatal.   The  runtime  library\ndefaults  to  \"haltonerror=0\" for ThreadSanitizer and UndefinedBehaviorSanitizer, while\ndefault value for AddressSanitizer is \"haltonerror=1\". This can be  overridden  through\nsetting the \"haltonerror\" flag in the corresponding environment variable.\n\nSyntax  without an explicit opts parameter is deprecated.  It is equivalent to specifying\nan opts list of:\n\nundefined,float-cast-overflow,float-divide-by-zero,bounds-strict\n"
                },
                {
                    "name": "-fsanitize-address-use-after-scope",
                    "content": "Enable sanitization of local variables to detect use-after-scope bugs.  The  option  sets\n-fstack-reuse to none.\n"
                },
                {
                    "name": "-fsanitize-trap",
                    "content": "The  -fsanitize-trap= option instructs the compiler to report for sanitizers mentioned in\ncomma-separated list of opts undefined behavior  using  \"builtintrap\"  rather  than  a\n\"libubsan\"  library  routine.   If this option is enabled for certain sanitizer, it takes\nprecedence over the -fsanitizer-recover= for that  sanitizer,  \"builtintrap\"  will  be\nemitted  and  be  fatal  regardless  of  whether  recovery  is  enabled or disabled using\n-fsanitize-recover=.\n\nThe advantage of this is that the \"libubsan\" library is not needed and is not linked  in,\nso this is usable even in freestanding environments.\n\nCurrently  this  feature  works  with -fsanitize=undefined (and its suboptions except for\n-fsanitize=vptr),  -fsanitize=float-cast-overflow,  -fsanitize=float-divide-by-zero   and\n-fsanitize=bounds-strict.   \"-fsanitize-trap=all\" can be also specified, which enables it\nfor           \"undefined\"           suboptions,           -fsanitize=float-cast-overflow,\n-fsanitize=float-divide-by-zero         and         -fsanitize=bounds-strict.          If\n\"-fsanitize-trap=undefined\" or \"-fsanitize-trap=all\" is  used  and  \"-fsanitize=vptr\"  is\nenabled   on   the   command  line,  the  instrumentation  is  silently  ignored  as  the\ninstrumentation always needs \"libubsan\" support, -fsanitize-trap=vptr is not allowed.\n"
                },
                {
                    "name": "-fsanitize-undefined-trap-on-error",
                    "content": "The   -fsanitize-undefined-trap-on-error   option    is    deprecated    equivalent    of\n-fsanitize-trap=all.\n"
                },
                {
                    "name": "-fsanitize-coverage=trace-pc",
                    "content": "Enable    coverage-guided    fuzzing   code   instrumentation.    Inserts   a   call   to\n\"sanitizercovtracepc\" into every basic block.\n"
                },
                {
                    "name": "-fsanitize-coverage=trace-cmp",
                    "content": "Enable   dataflow   guided   fuzzing   code   instrumentation.    Inserts   a   call   to\n\"sanitizercovtracecmp1\",  \"sanitizercovtracecmp2\", \"sanitizercovtracecmp4\"\nor \"sanitizercovtracecmp8\" for integral comparison with both  operands  variable  or\n\"sanitizercovtraceconstcmp1\",                   \"sanitizercovtraceconstcmp2\",\n\"sanitizercovtraceconstcmp4\"  or  \"sanitizercovtraceconstcmp8\"  for  integral\ncomparison     with     one    operand    constant,    \"sanitizercovtracecmpf\"    or\n\"sanitizercovtracecmpd\"     for     float     or     double     comparisons      and\n\"sanitizercovtraceswitch\" for switch statements.\n"
                },
                {
                    "name": "-fcf-protection=",
                    "content": "Enable  code  instrumentation  of  control-flow transfers to increase program security by\nchecking that target addresses of control-flow transfer instructions  (such  as  indirect\nfunction  call,  function  return, indirect jump) are valid.  This prevents diverting the\nflow of control to an unexpected target.   This  is  intended  to  protect  against  such\nthreats as Return-oriented Programming (ROP), and similarly call/jmp-oriented programming\n(COP/JOP).\n\nThe  value  \"branch\" tells the compiler to implement checking of validity of control-flow\ntransfer at the point of indirect branch instructions, i.e. call/jmp  instructions.   The\nvalue \"return\" implements checking of validity at the point of returning from a function.\nThe  value \"full\" is an alias for specifying both \"branch\" and \"return\". The value \"none\"\nturns off instrumentation.\n\nThe value \"check\" is used for the final link with link-time optimization (LTO).  An error\nis issued if LTO object files are compiled with different  -fcf-protection  values.   The\nvalue \"check\" is ignored at the compile time.\n\nThe  macro \"CET\" is defined when -fcf-protection is used.  The first bit of \"CET\"\nis set to 1 for the value \"branch\" and the second bit of \"CET\" is set to  1  for  the\n\"return\".\n\nYou  can also use the \"nocfcheck\" attribute to identify which functions and calls should\nbe skipped from instrumentation.\n\nCurrently the x86 GNU/Linux target provides an implementation based on Intel Control-flow\nEnforcement Technology (CET) which works for i686 processor or newer.\n\nNOTE: In Ubuntu 19.10 and later versions, -fcf-protection is enabled by  default  for  C,\nC++, ObjC, ObjC++, if none of -fno-cf-protection nor -fcf-protection=* are found.\n"
                },
                {
                    "name": "-fharden-compares",
                    "content": "For  every  logical test that survives gimple optimizations and is not the condition in a\nconditional branch (for example, conditions tested for conditional moves, or to store  in\nboolean  variables), emit extra code to compute and verify the reversed condition, and to\ncall    \"builtintrap\"    if    the    results    do    not    match.      Use     with\n-fharden-conditional-branches to cover all conditionals.\n"
                },
                {
                    "name": "-fharden-conditional-branches",
                    "content": "For  every  non-vectorized  conditional  branch  that survives gimple optimizations, emit\nextra code to compute and verify the reversed condition, and to call \"builtintrap\"  if\nthe result is unexpected.  Use with -fharden-compares to cover all conditionals.\n"
                },
                {
                    "name": "-fstack-protector",
                    "content": "Emit  extra  code to check for buffer overflows, such as stack smashing attacks.  This is\ndone by adding a guard variable to functions  with  vulnerable  objects.   This  includes\nfunctions that call \"alloca\", and functions with buffers larger than or equal to 8 bytes.\nThe  guards are initialized when a function is entered and then checked when the function\nexits.  If a guard check fails, an error message is printed and the program exits.   Only\nvariables  that  are  actually  allocated  on  the  stack  are considered, optimized away\nvariables or variables allocated in registers don't count.\n"
                },
                {
                    "name": "-fstack-protector-all",
                    "content": "Like -fstack-protector except that all functions are protected.\n"
                },
                {
                    "name": "-fstack-protector-strong",
                    "content": "Like -fstack-protector but includes additional functions to be protected ---  those  that\nhave  local  array  definitions,  or  have  references  to  local  frame addresses.  Only\nvariables that are actually  allocated  on  the  stack  are  considered,  optimized  away\nvariables or variables allocated in registers don't count.\n\nNOTE:  In Ubuntu 14.10 and later versions, -fstack-protector-strong is enabled by default\nfor C, C++, ObjC, ObjC++, if none of -fno-stack-protector, -nostdlib, nor  -ffreestanding\nare found.\n"
                },
                {
                    "name": "-fstack-protector-explicit",
                    "content": "Like  -fstack-protector  but only protects those functions which have the \"stackprotect\"\nattribute.\n"
                },
                {
                    "name": "-fstack-check",
                    "content": "Generate code to verify that you do not go beyond the boundary of the stack.  You  should\nspecify  this  flag  if  you are running in an environment with multiple threads, but you\nonly rarely need to specify it in a single-threaded environment since stack  overflow  is\nautomatically detected on nearly all systems if there is only one stack.\n\nNote  that  this switch does not actually cause checking to be done; the operating system\nor the language runtime must do that.  The switch causes generation  of  code  to  ensure\nthat they see the stack being extended.\n\nYou  can  additionally  specify  a  string parameter: no means no checking, generic means\nforce the use of old-style checking, specific means use the best checking method  and  is\nequivalent to bare -fstack-check.\n\nOld-style checking is a generic mechanism that requires no specific target support in the\ncompiler but comes with the following drawbacks:\n\n1.  Modified allocation strategy for large objects: they are always allocated dynamically\nif  their size exceeds a fixed threshold.  Note this may change the semantics of some\ncode.\n\n2.  Fixed limit on the size of the static frame of functions: when  it  is  topped  by  a\nparticular  function,  stack  checking is not reliable and a warning is issued by the\ncompiler.\n\n3.  Inefficiency: because of both  the  modified  allocation  strategy  and  the  generic\nimplementation, code performance is hampered.\n\nNote  that old-style stack checking is also the fallback method for specific if no target\nsupport has been added in the compiler.\n\n-fstack-check= is designed for  Ada's  needs  to  detect  infinite  recursion  and  stack\noverflows.  specific is an excellent choice when compiling Ada code.  It is not generally\nsufficient  to  protect  against  stack-clash attacks.  To protect against those you want\n-fstack-clash-protection.\n"
                },
                {
                    "name": "-fstack-clash-protection",
                    "content": "Generate code to prevent stack clash style attacks.  When this  option  is  enabled,  the\ncompiler  will  only allocate one page of stack space at a time and each page is accessed\nimmediately after allocation.  Thus, it prevents allocations from jumping over any  stack\nguard page provided by the operating system.\n\nMost  targets  do  not  fully  support stack clash protection.  However, on those targets\n-fstack-clash-protection      will      protect      dynamic      stack      allocations.\n-fstack-clash-protection may also provide limited protection for static stack allocations\nif the target supports -fstack-check=specific.\n\nNOTE:  In Ubuntu 19.10 and later versions, -fstack-clash-protection is enabled by default\nfor C, C++, ObjC, ObjC++, unless -fno-stack-clash-protection is found.\n"
                },
                {
                    "name": "-fstack-limit-register=_",
                    "content": ""
                },
                {
                    "name": "-fstack-limit-symbol=_",
                    "content": ""
                },
                {
                    "name": "-fno-stack-limit",
                    "content": "Generate code to ensure that the stack does not grow beyond a certain value,  either  the\nvalue  of a register or the address of a symbol.  If a larger stack is required, a signal\nis raised at run time.  For most targets, the signal is raised before the stack  overruns\nthe boundary, so it is possible to catch the signal without taking special precautions.\n\nFor instance, if the stack starts at absolute address 0x80000000 and grows downwards, you\ncan        use        the        flags       -fstack-limit-symbol=stacklimit       and\n-Wl,--defsym,stacklimit=0x7ffe0000 to enforce a stack limit of 128KB.  Note that  this\nmay only work with the GNU linker.\n\nYou  can  locally  override  stack  limit checking by using the \"nostacklimit\" function\nattribute.\n"
                },
                {
                    "name": "-fsplit-stack",
                    "content": "Generate code to automatically split  the  stack  before  it  overflows.   The  resulting\nprogram  has  a  discontiguous  stack which can only overflow if the program is unable to\nallocate any more memory.  This is most useful when running threaded programs, as  it  is\nno  longer  necessary  to  calculate  a  good stack size to use for each thread.  This is\ncurrently only implemented for the x86 targets running GNU/Linux.\n\nWhen code compiled with -fsplit-stack calls code compiled  without  -fsplit-stack,  there\nmay not be much stack space available for the latter code to run.  If compiling all code,\nincluding  library  code, with -fsplit-stack is not an option, then the linker can fix up\nthese calls so that the code compiled without -fsplit-stack always  has  a  large  stack.\nSupport  for  this  is  implemented  in  the gold linker in GNU binutils release 2.21 and\nlater.\n"
                },
                {
                    "name": "-fvtable-verify=",
                    "content": "This option is only available when compiling C++ code.  It turns on  (or  off,  if  using\n-fvtable-verify=none)  the  security feature that verifies at run time, for every virtual\ncall, that the vtable pointer through which the call is made is valid for the type of the\nobject, and has not been corrupted or overwritten.   If  an  invalid  vtable  pointer  is\ndetected  at  run  time, an error is reported and execution of the program is immediately\nhalted.\n\nThis option causes run-time data structures to be built at  program  startup,  which  are\nused  for  verifying the vtable pointers.  The options std and preinit control the timing\nof when these data structures are built.  In both cases the  data  structures  are  built\nbefore execution reaches \"main\".  Using -fvtable-verify=std causes the data structures to\nbe    built    after    shared    libraries    have    been   loaded   and   initialized.\n-fvtable-verify=preinit causes them to be built before shared libraries have been  loaded\nand initialized.\n\nIf  this  option  appears  multiple  times  in  the  command  line  with different values\nspecified, none takes highest priority over both std and preinit; preinit takes  priority\nover std.\n"
                },
                {
                    "name": "-fvtv-debug",
                    "content": "When  used  in  conjunction  with  -fvtable-verify=std or -fvtable-verify=preinit, causes\ndebug versions of the runtime functions for the vtable verification feature to be called.\nThis flag also causes the compiler to log information  about  which  vtable  pointers  it\nfinds  for  each class.  This information is written to a file named vtvsetptrdata.log\nin the directory named by the environment variable VTVLOGSDIR if that is defined or the\ncurrent working directory otherwise.\n\nNote:  This feature appends data to the log file. If you want a fresh log file,  be  sure\nto delete any existing one.\n"
                },
                {
                    "name": "-fvtv-counts",
                    "content": "This  is  a  debugging  flag.   When  used  in  conjunction  with  -fvtable-verify=std or\n-fvtable-verify=preinit, this causes the compiler to keep track of the  total  number  of\nvirtual  calls  it encounters and the number of verifications it inserts.  It also counts\nthe number of calls to certain run-time library functions that it inserts and  logs  this\ninformation  for  each  compilation unit.  The compiler writes this information to a file\nnamed vtvcountdata.log in the directory named by the environment variable  VTVLOGSDIR\nif  that  is defined or the current working directory otherwise.  It also counts the size\nof  the  vtable  pointer  sets  for  each  class,  and   writes   this   information   to\nvtvclasssetsizes.log in the same directory.\n\nNote:   This  feature  appends data to the log files.  To get fresh log files, be sure to\ndelete any existing ones.\n"
                },
                {
                    "name": "-finstrument-functions",
                    "content": "Generate instrumentation calls for entry and exit  to  functions.   Just  after  function\nentry  and  just  before function exit, the following profiling functions are called with\nthe  address  of  the  current  function  and  its  call  site.   (On   some   platforms,\n\"builtinreturnaddress\"  does  not  work beyond the current function, so the call site\ninformation may not be available to the profiling functions otherwise.)\n\nvoid cygprofilefuncenter (void *thisfn,\nvoid *callsite);\nvoid cygprofilefuncexit  (void *thisfn,\nvoid *callsite);\n\nThe first argument is the address of the start of the  current  function,  which  may  be\nlooked up exactly in the symbol table.\n\nThis  instrumentation is also done for functions expanded inline in other functions.  The\nprofiling calls indicate where, conceptually, the inline function is entered and  exited.\nThis  means  that  addressable versions of such functions must be available.  If all your\nuses of a function are expanded inline, this may mean an  additional  expansion  of  code\nsize.   If  you  use  \"extern  inline\"  in  your  C  code, an addressable version of such\nfunctions must be provided.  (This is normally the case anyway, but if you get lucky  and\nthe  optimizer  always  expands  the functions inline, you might have gotten away without\nproviding static copies.)\n\nA function may be given  the  attribute  \"noinstrumentfunction\",  in  which  case  this\ninstrumentation  is not done.  This can be used, for example, for the profiling functions\nlisted above,  high-priority  interrupt  routines,  and  any  functions  from  which  the\nprofiling  functions  cannot  safely be called (perhaps signal handlers, if the profiling\nroutines generate output or allocate memory).\n"
                },
                {
                    "name": "-finstrument-functions-once",
                    "content": "This is similar to -finstrument-functions, but the profiling functions  are  called  only\nonce  per  instrumented  function,  i.e. the first profiling function is called after the\nfirst entry into the instrumented function and the second profiling  function  is  called\nbefore the exit corresponding to this first entry.\n\nThe  definition  of  \"once\"  for the purpose of this option is a little vague because the\nimplementation is not protected against data races.  As a result, the implementation only\nguarantees that the profiling functions are called at least once per process and at  most\nonce  per  thread, but the calls are always paired, that is to say, if a thread calls the\nfirst function, then it will call the second function, unless it never reaches  the  exit\nof the instrumented function.\n"
                },
                {
                    "name": "-finstrument-functions-exclude-file-list=_",
                    "content": "Set  the list of functions that are excluded from instrumentation (see the description of\n-finstrument-functions).  If the file that contains a function  definition  matches  with\none of file, then that function is not instrumented.  The match is done on substrings: if\nthe file parameter is a substring of the file name, it is considered to be a match.\n\nFor example:\n\n-finstrument-functions-exclude-file-list=/bits/stl,include/sys\n\nexcludes  any  inline  function  defined  in  files  whose pathnames contain /bits/stl or\ninclude/sys.\n\nIf, for some reason, you want to include letter , in one of sym, write  ,.  For  example,\n-finstrument-functions-exclude-file-list=',,tmp'  (note  the single quote surrounding the\noption).\n"
                },
                {
                    "name": "-finstrument-functions-exclude-function-list=_",
                    "content": "This is similar to -finstrument-functions-exclude-file-list, but  this  option  sets  the\nlist  of  function  names  to  be excluded from instrumentation.  The function name to be\nmatched is its user-visible name, such as \"vector<int> blah(const  vector<int>  &)\",  not\nthe  internal  mangled  name  (e.g.,  \"Z4blahRSt6vectorIiSaIiEE\").  The match is done on\nsubstrings: if the sym parameter is a substring of the function name, it is considered to\nbe a match.  For C99 and C++ extended identifiers, the function name  must  be  given  in\nUTF-8, not using universal character names.\n"
                },
                {
                    "name": "-fpatchable-function-entry=_",
                    "content": "Generate  N  NOPs  right at the beginning of each function, with the function entry point\nbefore the Mth NOP.  If M is omitted, it defaults to 0 so the function  entry  points  to\nthe address just at the first NOP.  The NOP instructions reserve extra space which can be\nused  to patch in any desired instrumentation at run time, provided that the code segment\nis writable.  The amount of space is controllable indirectly via the number of NOPs;  the\nNOP  instruction used corresponds to the instruction emitted by the internal GCC back-end\ninterface \"gennop\".  This behavior  is  target-specific  and  may  also  depend  on  the\narchitecture variant and/or other compilation options.\n\nFor  run-time  identification, the starting addresses of these areas, which correspond to\ntheir  respective  function  entries  minus  M,  are  additionally   collected   in   the\n\"patchablefunctionentries\" section of the resulting binary.\n\nNote   that   the  value  of  \"attribute  ((patchablefunctionentry  (N,M)))\"  takes\nprecedence over command-line option -fpatchable-function-entry=N,M.  This can be used  to\nincrease the area size or to remove it completely on a single function.  If \"N=0\", no pad\nlocation is recorded.\n\nThe  NOP  instructions  are inserted at---and maybe before, depending on M---the function\nentry address, even before the prologue.  On PowerPC with the ELFv2 ABI, for  a  function\nwith dual entry points, the local entry point is this function entry address.\n\nThe  maximum  value  of  N and M is 65535.  On PowerPC with the ELFv2 ABI, for a function\nwith dual entry points, the supported values for M are 0, 2, 6 and 14.\n"
                },
                {
                    "name": "Options Controlling the Preprocessor",
                    "content": "These options control the C preprocessor, which is run on each C source  file  before  actual\ncompilation.\n\nIf  you  use the -E option, nothing is done except preprocessing.  Some of these options make\nsense only together with -E because they cause the preprocessor output to be  unsuitable  for\nactual compilation.\n\nIn addition to the options listed here, there are a number of options to control search paths\nfor  include  files  documented  in  Directory  Options.   Options  to  control  preprocessor\ndiagnostics are listed in Warning Options.\n"
                },
                {
                    "name": "-D _",
                    "content": "Predefine name as a macro, with definition 1.\n",
                    "flag": "-D"
                },
                {
                    "name": "-D _",
                    "content": "The contents of definition are  tokenized  and  processed  as  if  they  appeared  during\ntranslation  phase  three  in  a  #define  directive.   In  particular, the definition is\ntruncated by embedded newline characters.\n\nIf you are invoking the preprocessor from a shell or shell-like program you may  need  to\nuse  the  shell's quoting syntax to protect characters such as spaces that have a meaning\nin the shell syntax.\n\nIf you wish to define a function-like macro on the command line, write its argument  list\nwith surrounding parentheses before the equals sign (if any).  Parentheses are meaningful\nto   most   shells,   so   you   should   quote   the   option.    With   sh   and   csh,\n-D'name(args...)=definition' works.\n\n-D and -U options are processed in the order they are given on  the  command  line.   All\n-imacros file and -include file options are processed after all -D and -U options.\n",
                    "flag": "-D"
                },
                {
                    "name": "-U _",
                    "content": "Cancel any previous definition of name, either built in or provided with a -D option.\n",
                    "flag": "-U"
                },
                {
                    "name": "-include _",
                    "content": "Process  file  as  if  \"#include \"file\"\" appeared as the first line of the primary source\nfile.  However, the first directory searched  for  file  is  the  preprocessor's  working\ndirectory  instead of the directory containing the main source file.  If not found there,\nit is searched for in the remainder of the \"#include \"...\"\" search chain as normal.\n\nIf multiple -include options are given, the files are included in the order  they  appear\non the command line.\n"
                },
                {
                    "name": "-imacros _",
                    "content": "Exactly  like  -include, except that any output produced by scanning file is thrown away.\nMacros it defines remain defined.  This allows you to  acquire  all  the  macros  from  a\nheader without also processing its declarations.\n\nAll files specified by -imacros are processed before all files specified by -include.\n"
                },
                {
                    "name": "-undef",
                    "content": "Do  not  predefine  any  system-specific or GCC-specific macros.  The standard predefined\nmacros remain defined.\n"
                },
                {
                    "name": "-pthread",
                    "content": "Define additional macros required for using the POSIX threads library.   You  should  use\nthis  option  consistently for both compilation and linking.  This option is supported on\nGNU/Linux targets, most other Unix derivatives, and also on x86 Cygwin and MinGW targets.\n"
                },
                {
                    "name": "-M",
                    "content": "describing  the  dependencies of the main source file.  The preprocessor outputs one make\nrule containing the object file name for that source file, a colon, and the names of  all\nthe  included  files,  including  those  coming  from  -include  or -imacros command-line\noptions.\n\nUnless specified explicitly (with -MT or -MQ), the object file name consists of the  name\nof  the source file with any suffix replaced with object file suffix and with any leading\ndirectory parts removed.  If there are many included files then the rule  is  split  into\nseveral lines using \\-newline.  The rule has no commands.\n\nThis  option  does  not  suppress the preprocessor's debug output, such as -dM.  To avoid\nmixing such debug output with the dependency rules  you  should  explicitly  specify  the\ndependency output file with -MF, or use an environment variable like DEPENDENCIESOUTPUT.\nDebug output is still sent to the regular output stream as normal.\n\nPassing -M to the driver implies -E, and suppresses warnings with an implicit -w.\n",
                    "flag": "-M"
                },
                {
                    "name": "-MM  -M",
                    "content": "header files that are included, directly or indirectly, from such a header.\n\nThis implies that the choice of angle brackets or double quotes in an #include  directive\ndoes not in itself determine whether that header appears in -MM dependency output.\n",
                    "flag": "-M"
                },
                {
                    "name": "-MF _",
                    "content": "When  used  with  -M  or  -MM,  specifies a file to write the dependencies to.  If no -MF\nswitch is given the preprocessor sends  the  rules  to  the  same  place  it  would  send\npreprocessed output.\n\nWhen  used  with  the  driver  options  -MD or -MMD, -MF overrides the default dependency\noutput file.\n\nIf file is -, then the dependencies are written to stdout.\n"
                },
                {
                    "name": "-MG  -M  -MG",
                    "content": "missing  header  files  are  generated files and adds them to the dependency list without\nraising an error.   The  dependency  filename  is  taken  directly  from  the  \"#include\"\ndirective  without  prepending  any  path.  -MG also suppresses preprocessed output, as a\nmissing header file renders this useless.\n\nThis feature is used in automatic updating of makefiles.\n",
                    "flag": "-M"
                },
                {
                    "name": "-Mno-modules",
                    "content": "Disable dependency generation for compiled module interfaces.\n"
                },
                {
                    "name": "-MP",
                    "content": "file, causing each to depend on nothing.  These dummy rules work around errors make gives\nif you remove header files without updating the Makefile to match.\n\nThis is typical output:\n\ntest.o: test.c test.h\n\ntest.h:\n"
                },
                {
                    "name": "-MT _",
                    "content": "Change the target of the rule emitted by dependency generation.  By default CPP takes the\nname of the main input file, deletes any directory components and any file suffix such as\n.c, and appends the platform's usual object suffix.  The result is the target.\n\nAn -MT option sets the target to be exactly the string you specify.  If you want multiple\ntargets, you can specify them as a single argument to -MT, or use multiple -MT options.\n\nFor example, -MT '$(objpfx)foo.o' might give\n\n$(objpfx)foo.o: foo.c\n"
                },
                {
                    "name": "-MQ _",
                    "content": "Same   as   -MT,   but   it   quotes   any   characters   which   are  special  to  Make.\n-MQ '$(objpfx)foo.o' gives\n\n$$(objpfx)foo.o: foo.c\n\nThe default target is automatically quoted, as if it were given with -MQ.\n"
                },
                {
                    "name": "-MD -MD  -M -MF _ -E",
                    "content": "file  based on whether an -o option is given.  If it is, the driver uses its argument but\nwith a suffix of .d, otherwise it takes the name of the input file, removes any directory\ncomponents and suffix, and applies a .d suffix.\n\nIf -MD is used in conjunction with -E,  any  -o  switch  is  understood  to  specify  the\ndependency output file, but if used without -E, each -o is understood to specify a target\nobject file.\n\nSince  -E  is not implied, -MD can be used to generate a dependency output file as a side\neffect of the compilation process.\n",
                    "flag": "-E"
                },
                {
                    "name": "-MMD",
                    "content": "Like -MD except mention only user header files, not system header files.\n"
                },
                {
                    "name": "-fpreprocessed",
                    "content": "Indicate to the preprocessor that the input file has  already  been  preprocessed.   This\nsuppresses  things  like  macro expansion, trigraph conversion, escaped newline splicing,\nand processing of  most  directives.   The  preprocessor  still  recognizes  and  removes\ncomments,  so  that  you  can  pass  a  file preprocessed with -C to the compiler without\nproblems.  In this mode the integrated preprocessor is little more than a  tokenizer  for\nthe front ends.\n\n-fpreprocessed  is  implicit  if the input file has one of the extensions .i, .ii or .mi.\nThese are the extensions that GCC uses for preprocessed files created by -save-temps.\n"
                },
                {
                    "name": "-fdirectives-only",
                    "content": "When preprocessing, handle directives, but do not expand macros.\n\nThe option's behavior depends on the -E and -fpreprocessed options.\n\nWith -E, preprocessing is limited to  the  handling  of  directives  such  as  \"#define\",\n\"#ifdef\",  and  \"#error\".   Other  preprocessor  operations,  such as macro expansion and\ntrigraph conversion are not  performed.   In  addition,  the  -dD  option  is  implicitly\nenabled.\n\nWith  -fpreprocessed,  predefinition of command line and most builtin macros is disabled.\nMacros such as \"LINE\", which are contextually dependent, are handled normally.   This\nenables compilation of files previously preprocessed with \"-E -fdirectives-only\".\n\nWith  both  -E  and  -fpreprocessed,  the rules for -fpreprocessed take precedence.  This\nenables full preprocessing of files previously preprocessed with \"-E -fdirectives-only\".\n"
                },
                {
                    "name": "-fdollars-in-identifiers",
                    "content": "Accept $ in identifiers.\n"
                },
                {
                    "name": "-fextended-identifiers",
                    "content": "Accept universal character names and extended characters in identifiers.  This option  is\nenabled by default for C99 (and later C standard versions) and C++.\n"
                },
                {
                    "name": "-fno-canonical-system-headers",
                    "content": "When preprocessing, do not shorten system header paths with canonicalization.\n"
                },
                {
                    "name": "-fmax-include-depth=_",
                    "content": "Set the maximum depth of the nested #include. The default is 200.\n"
                },
                {
                    "name": "-ftabstop=_",
                    "content": "Set  the  distance  between tab stops.  This helps the preprocessor report correct column\nnumbers in warnings or errors, even if tabs appear on the line.  If  the  value  is  less\nthan 1 or greater than 100, the option is ignored.  The default is 8.\n"
                },
                {
                    "name": "-ftrack-macro-expansion",
                    "content": "Track  locations  of  tokens  across  macro  expansions. This allows the compiler to emit\ndiagnostic about the current macro expansion stack when a compilation error occurs  in  a\nmacro  expansion.  Using this option makes the preprocessor and the compiler consume more\nmemory. The level parameter can be used  to  choose  the  level  of  precision  of  token\nlocation  tracking  thus decreasing the memory consumption if necessary. Value 0 of level\nde-activates this option. Value 1 tracks tokens locations in a degraded mode for the sake\nof minimal memory overhead. In this mode all tokens resulting from the  expansion  of  an\nargument of a function-like macro have the same location. Value 2 tracks tokens locations\ncompletely. This value is the most memory hungry.  When this option is given no argument,\nthe default parameter value is 2.\n\nNote that \"-ftrack-macro-expansion=2\" is activated by default.\n"
                },
                {
                    "name": "-fmacro-prefix-map=_",
                    "content": "When   preprocessing   files  residing  in  directory  old,  expand  the  \"FILE\"  and\n\"BASEFILE\" macros as if the files resided in directory new  instead.   This  can  be\nused to change an absolute path to a relative path by using . for new which can result in\nmore  reproducible  builds  that  are  location  independent.   This  option also affects\n\"builtinFILE()\"    during    compilation.     See    also    -ffile-prefix-map     and\n-fcanon-prefix-map.\n"
                },
                {
                    "name": "-fexec-charset=_",
                    "content": "Set the execution character set, used for string and character constants.  The default is\nUTF-8.  charset can be any encoding supported by the system's \"iconv\" library routine.\n"
                },
                {
                    "name": "-fwide-exec-charset=_",
                    "content": "Set  the wide execution character set, used for wide string and character constants.  The\ndefault is one of UTF-32BE, UTF-32LE, UTF-16BE, or UTF-16LE, whichever corresponds to the\nwidth of \"wchart\" and the big-endian or little-endian byte order  being  used  for  code\ngeneration.   As  with  -fexec-charset,  charset  can  be  any  encoding supported by the\nsystem's \"iconv\" library routine; however, you will have problems with encodings that  do\nnot fit exactly in \"wchart\".\n"
                },
                {
                    "name": "-finput-charset=_",
                    "content": "Set  the  input  character  set, used for translation from the character set of the input\nfile to the source character set used by GCC.  If the locale does  not  specify,  or  GCC\ncannot  get  this  information  from  the  locale,  the  default  is  UTF-8.  This can be\noverridden by either the locale or this command-line option.  Currently the  command-line\noption  takes precedence if there's a conflict.  charset can be any encoding supported by\nthe system's \"iconv\" library routine.\n"
                },
                {
                    "name": "-fpch-deps",
                    "content": "When using precompiled headers, this flag causes the dependency-output flags to also list\nthe files from the  precompiled  header's  dependencies.   If  not  specified,  only  the\nprecompiled  header  are  listed  and  not the files that were used to create it, because\nthose files are not consulted when a precompiled header is used.\n"
                },
                {
                    "name": "-fpch-preprocess",
                    "content": "This option allows use of a precompiled header together with -E.  It  inserts  a  special\n\"#pragma\",  \"#pragma GCC pchpreprocess \"filename\"\" in the output to mark the place where\nthe precompiled header was found, and its filename.  When -fpreprocessed is in  use,  GCC\nrecognizes this \"#pragma\" and loads the PCH.\n\nThis  option  is off by default, because the resulting preprocessed output is only really\nsuitable as input to GCC.  It is switched on by -save-temps.\n\nYou should not write this \"#pragma\" in your own code, but it is safe to edit the filename\nif the PCH file is available in a different location.  The filename may be absolute or it\nmay be relative to GCC's current directory.\n"
                },
                {
                    "name": "-fworking-directory",
                    "content": "Enable generation of linemarkers in the preprocessor output that let  the  compiler  know\nthe current working directory at the time of preprocessing.  When this option is enabled,\nthe  preprocessor  emits,  after  the  initial  linemarker,  a second linemarker with the\ncurrent working directory followed by two slashes.  GCC uses this  directory,  when  it's\npresent  in  the  preprocessed  input,  as  the  directory emitted as the current working\ndirectory in some debugging information formats.  This option is  implicitly  enabled  if\ndebugging  information  is  enabled,  but  this  can  be  inhibited with the negated form\n-fno-working-directory.  If the -P flag is present in the command line, this  option  has\nno effect, since no \"#line\" directives are emitted whatsoever.\n"
                },
                {
                    "name": "-A _",
                    "content": "Make an assertion with the predicate predicate and answer answer.  This form is preferred\nto the older form -A predicate(answer), which is still supported, because it does not use\nshell special characters.\n",
                    "flag": "-A"
                },
                {
                    "name": "-A -_",
                    "content": "Cancel an assertion with the predicate predicate and answer answer.\n",
                    "flag": "-A"
                },
                {
                    "name": "-C",
                    "content": "comments in processed directives, which are deleted along with the directive.\n\nYou should be prepared for side effects when using -C;  it  causes  the  preprocessor  to\ntreat  comments  as  tokens  in  their own right.  For example, comments appearing at the\nstart of what would be a directive line have the effect of  turning  that  line  into  an\nordinary source line, since the first token on the line is no longer a #.\n",
                    "flag": "-C"
                },
                {
                    "name": "-CC  -C",
                    "content": "comments contained within macros are also passed through to the  output  file  where  the\nmacro is expanded.\n\nIn  addition  to  the  side effects of the -C option, the -CC option causes all C++-style\ncomments inside a macro to be converted to C-style comments.  This is  to  prevent  later\nuse of that macro from inadvertently commenting out the remainder of the source line.\n\nThe -CC option is generally used to support lint comments.\n",
                    "flag": "-C"
                },
                {
                    "name": "-P",
                    "content": "useful when running the preprocessor on something that is not C code, and will be sent to\na program which might be confused by the linemarkers.\n",
                    "flag": "-P"
                },
                {
                    "name": "-traditional",
                    "content": ""
                },
                {
                    "name": "-traditional-cpp",
                    "content": "Try to imitate the behavior  of  pre-standard  C  preprocessors,  as  opposed  to  ISO  C\npreprocessors.  See the GNU CPP manual for details.\n\nNote  that GCC does not otherwise attempt to emulate a pre-standard C compiler, and these\noptions are only supported with the -E switch, or when invoking CPP explicitly.\n"
                },
                {
                    "name": "-trigraphs",
                    "content": "Support ISO C trigraphs.  These are three-character sequences, all starting with ??, that\nare defined by ISO C to stand for single characters.  For example, ??/ stands for  \\,  so\n'??/n' is a character constant for a newline.\n\nThe nine trigraphs and their replacements are\n\nTrigraph:       ??(  ??)  ??<  ??>  ??=  ??/  ??'  ??!  ??-\nReplacement:      [    ]    {    }    #    \\    ^    |    ~\n\nBy  default,  GCC  ignores  trigraphs, but in standard-conforming modes it converts them.\nSee the -std and -ansi options.\n"
                },
                {
                    "name": "-remap",
                    "content": "Enable special code to work around file systems which only permit very short file  names,\nsuch as MS-DOS.\n"
                },
                {
                    "name": "-H",
                    "content": "name is indented to show how deep in the #include stack it is.  Precompiled header  files\nare  also  printed,  even  if they are found to be invalid; an invalid precompiled header\nfile is printed with ...x and a valid one with ...! .\n",
                    "flag": "-H"
                },
                {
                    "name": "-d_",
                    "content": "Says to make debugging dumps during compilation  as  specified  by  letters.   The  flags\ndocumented here are those relevant to the preprocessor.  Other letters are interpreted by\nthe compiler proper, or reserved for future versions of GCC, and so are silently ignored.\nIf you specify letters whose behavior conflicts, the result is undefined.\n\n-dM Instead  of  the  normal  output,  generate  a list of #define directives for all the\nmacros defined during the execution of the preprocessor, including predefined macros.\nThis gives you a way of finding out  what  is  predefined  in  your  version  of  the\npreprocessor.  Assuming you have no file foo.h, the command\n\ntouch foo.h; cpp -dM foo.h\n\nshows all the predefined macros.\n\nIf  you  use  -dM  without  the  -E  option,  -dM  is  interpreted  as  a synonym for\n-fdump-rtl-mach.\n\n-dD Like -dM except in two respects: it does not include the predefined  macros,  and  it\noutputs  both  the #define directives and the result of preprocessing.  Both kinds of\noutput go to the standard output file.\n\n-dN Like -dD, but emit only the macro names, not their expansions.\n\n-dI Output #include directives in addition to the result of preprocessing.\n\n-dU Like -dD except that only macros that are expanded, or whose definedness is tested in\npreprocessor directives, are output; the output is delayed until the use or  test  of\nthe  macro;  and #undef directives are also output for macros tested but undefined at\nthe time.\n"
                },
                {
                    "name": "-fdebug-cpp",
                    "content": "This option is only useful for debugging GCC.  When used from CPP or with  -E,  it  dumps\ndebugging  information about location maps.  Every token in the output is preceded by the\ndump of the map its location belongs to.\n\nWhen used from GCC without -E, this option has no effect.\n"
                },
                {
                    "name": "-Wp,_",
                    "content": "You can use -Wp,option to bypass the compiler driver and pass option directly through  to\nthe  preprocessor.   If  option contains commas, it is split into multiple options at the\ncommas.  However, many options are modified, translated or interpreted  by  the  compiler\ndriver  before  being  passed  to the preprocessor, and -Wp forcibly bypasses this phase.\nThe preprocessor's direct interface is undocumented and subject to  change,  so  whenever\npossible you should avoid using -Wp and let the driver handle the options instead.\n"
                },
                {
                    "name": "-Xpreprocessor _",
                    "content": "Pass option as an option to the preprocessor.  You can use this to supply system-specific\npreprocessor options that GCC does not recognize.\n\nIf  you want to pass an option that takes an argument, you must use -Xpreprocessor twice,\nonce for the option and once for the argument.\n"
                },
                {
                    "name": "-no-integrated-cpp",
                    "content": "Perform preprocessing as a separate pass before compilation.  By  default,  GCC  performs\npreprocessing as an integrated part of input tokenization and parsing.  If this option is\nprovided,  the  appropriate  language  front end (cc1, cc1plus, or cc1obj for C, C++, and\nObjective-C, respectively) is instead invoked twice, once for preprocessing only and once\nfor actual compilation  of  the  preprocessed  input.   This  option  may  be  useful  in\nconjunction  with  the  -B  or  -wrapper  options to specify an alternate preprocessor or\nperform additional processing of the program  source  between  normal  preprocessing  and\ncompilation.\n"
                },
                {
                    "name": "-flarge-source-files",
                    "content": "Adjust  GCC to expect large source files, at the expense of slower compilation and higher\nmemory usage.\n\nSpecifically, GCC normally tracks both column numbers  and  line  numbers  within  source\nfiles  and it normally prints both of these numbers in diagnostics.  However, once it has\nprocessed a certain number of source lines, it stops tracking  column  numbers  and  only\ntracks  line  numbers.  This means that diagnostics for later lines do not include column\nnumbers.  It also means that options like -Wmisleading-indentation cease to work at  that\npoint, although the compiler prints a note if this happens.  Passing -flarge-source-files\nsignificantly  increases  the number of source lines that GCC can process before it stops\ntracking columns.\n"
                },
                {
                    "name": "Passing Options to the Assembler",
                    "content": "You can pass options to the assembler.\n"
                },
                {
                    "name": "-Wa,_",
                    "content": "Pass option as an option to the assembler.  If option contains commas, it is  split  into\nmultiple options at the commas.\n"
                },
                {
                    "name": "-Xassembler _",
                    "content": "Pass  option  as  an option to the assembler.  You can use this to supply system-specific\nassembler options that GCC does not recognize.\n\nIf you want to pass an option that takes an argument, you  must  use  -Xassembler  twice,\nonce for the option and once for the argument.\n"
                },
                {
                    "name": "Options for Linking",
                    "content": "These  options  come into play when the compiler links object files into an executable output\nfile.  They are meaningless if the compiler is not doing a link step.\n\nobject-file-name\nA file name that does not end in a special recognized suffix is  considered  to  name  an\nobject  file  or  library.   (Object files are distinguished from libraries by the linker\naccording to the file contents.)  If linking is done, these  object  files  are  used  as\ninput to the linker.\n"
                },
                {
                    "name": "-c",
                    "content": "",
                    "flag": "-c"
                },
                {
                    "name": "-S",
                    "content": "",
                    "flag": "-S"
                },
                {
                    "name": "-E",
                    "content": "not be used as arguments.\n",
                    "flag": "-E"
                },
                {
                    "name": "-flinker-output=_",
                    "content": "This  option  controls code generation of the link-time optimizer.  By default the linker\noutput is automatically determined by the linker plugin.  For debugging the compiler  and\nif incremental linking with a non-LTO object file is desired, it may be useful to control\nthe type manually.\n\nIf  type  is exec, code generation produces a static binary. In this case -fpic and -fpie\nare both disabled.\n\nIf type is dyn, code generation produces a shared library.  In this case -fpic  or  -fPIC\nis  preserved,  but  not  enabled  automatically.   This allows to build shared libraries\nwithout position-independent code on architectures where this is possible, i.e. on x86.\n\nIf type is pie, code generation produces an -fpie executable.  This  results  in  similar\noptimizations as exec except that -fpie is not disabled if specified at compilation time.\n\nIf  type  is  rel,  the  compiler assumes that incremental linking is done.  The sections\ncontaining intermediate code for link-time optimization are  merged,  pre-optimized,  and\noutput  to  the  resulting  object  file. In addition, if -ffat-lto-objects is specified,\nbinary code is  produced  for  future  non-LTO  linking.  The  object  file  produced  by\nincremental linking is smaller than a static library produced from the same object files.\nAt  link  time  the result of incremental linking also loads faster than a static library\nassuming that the majority of objects in the library are used.\n\nFinally nolto-rel configures the compiler for incremental linking where  code  generation\nis  forced,  a  final  binary  is produced, and the intermediate code for later link-time\noptimization is stripped. When multiple object files are linked  together  the  resulting\ncode  is better optimized than with link-time optimizations disabled (for example, cross-\nmodule inlining happens), but most of benefits of whole program optimizations are lost.\n\nDuring the incremental link (by -r) the linker  plugin  defaults  to  rel.  With  current\ninterfaces  to  GNU Binutils it is however not possible to incrementally link LTO objects\nand non-LTO objects into a  single  mixed  object  file.   If  any  of  object  files  in\nincremental  link  cannot  be used for link-time optimization, the linker plugin issues a\nwarning and uses nolto-rel. To maintain whole program optimization, it is recommended  to\nlink  such  objects into static library instead. Alternatively it is possible to use H.J.\nLu's binutils with support for mixed objects.\n"
                },
                {
                    "name": "-fuse-ld=bfd",
                    "content": "Use the bfd linker instead of the default linker.\n"
                },
                {
                    "name": "-fuse-ld=gold",
                    "content": "Use the gold linker instead of the default linker.\n"
                },
                {
                    "name": "-fuse-ld=lld",
                    "content": "Use the LLVM lld linker instead of the default linker.\n"
                },
                {
                    "name": "-fuse-ld=mold",
                    "content": "Use the Modern Linker (mold) instead of the default linker.\n"
                },
                {
                    "name": "-l_",
                    "content": ""
                },
                {
                    "name": "-l _",
                    "content": "Search the library named library when linking.  (The second alternative with the  library\nas a separate argument is only for POSIX compliance and is not recommended.)\n\nThe  -l  option  is  passed  directly  to  the  linker  by  GCC.   Refer  to  your linker\ndocumentation for exact details.  The  general  description  below  applies  to  the  GNU\nlinker.\n\nThe  linker  searches  a  standard  list of directories for the library.  The directories\nsearched include several standard system directories plus any that you specify with -L.\n\nStatic libraries are archives of object files, and have  file  names  like  liblibrary.a.\nSome   targets   also   support   shared  libraries,  which  typically  have  names  like\nliblibrary.so.  If  both  static  and  shared  libraries  are  found,  the  linker  gives\npreference to linking with the shared library unless the -static option is used.\n\nIt makes a difference where in the command you write this option; the linker searches and\nprocesses  libraries  and  object files in the order they are specified.  Thus, foo.o -lz\nbar.o searches library z after file foo.o but before bar.o.  If bar.o refers to functions\nin z, those functions may not be loaded.\n",
                    "flag": "-l"
                },
                {
                    "name": "-lobjc",
                    "content": "You need this special case  of  the  -l  option  in  order  to  link  an  Objective-C  or\nObjective-C++ program.\n"
                },
                {
                    "name": "-nostartfiles",
                    "content": "Do not use the standard system startup files when linking.  The standard system libraries\nare used normally, unless -nostdlib, -nolibc, or -nodefaultlibs is used.\n"
                },
                {
                    "name": "-nodefaultlibs",
                    "content": "Do  not  use  the standard system libraries when linking.  Only the libraries you specify\nare passed to the linker, and options specifying linkage of the system libraries, such as\n-static-libgcc or -shared-libgcc, are ignored.   The  standard  startup  files  are  used\nnormally, unless -nostartfiles is used.\n\nThe  compiler  may  generate  calls to \"memcmp\", \"memset\", \"memcpy\" and \"memmove\".  These\nentries are usually resolved by entries in libc.  These entry points should  be  supplied\nthrough some other mechanism when this option is specified.\n"
                },
                {
                    "name": "-nolibc",
                    "content": "Do not use the C library or system libraries tightly coupled with it when linking.  Still\nlink with the startup files, libgcc or toolchain provided language support libraries such\nas  libgnat,  libgfortran or libstdc++ unless options preventing their inclusion are used\nas well.  This typically removes -lc from the  link  command  line,  as  well  as  system\nlibraries  that normally go with it and become meaningless when absence of a C library is\nassumed, for example -lpthread or -lm in some configurations.  This is intended for bare-\nboard targets when there is indeed no C library available.\n"
                },
                {
                    "name": "-nostdlib",
                    "content": "Do not use the standard system startup files or libraries when linking.  No startup files\nand only the libraries you specify are passed  to  the  linker,  and  options  specifying\nlinkage of the system libraries, such as -static-libgcc or -shared-libgcc, are ignored.\n\nThe  compiler  may  generate  calls to \"memcmp\", \"memset\", \"memcpy\" and \"memmove\".  These\nentries are usually resolved by entries in libc.  These entry points should  be  supplied\nthrough some other mechanism when this option is specified.\n\nOne  of  the  standard  libraries bypassed by -nostdlib and -nodefaultlibs is libgcc.a, a\nlibrary of internal subroutines which GCC uses to  overcome  shortcomings  of  particular\nmachines, or special needs for some languages.\n\nIn  most  cases,  you need libgcc.a even when you want to avoid other standard libraries.\nIn other words, when you specify -nostdlib or -nodefaultlibs you should  usually  specify\n-lgcc  as  well.   This  ensures  that  you have no unresolved references to internal GCC\nlibrary subroutines.  (An example of such an internal subroutine  is  \"main\",  used  to\nensure C++ constructors are called.)\n"
                },
                {
                    "name": "-nostdlib++",
                    "content": "Do not implicitly link with standard C++ libraries.\n"
                },
                {
                    "name": "-e _",
                    "content": "--entry=entry\nSpecify  that  the  program  entry  point  is  entry.  The argument is interpreted by the\nlinker; the GNU linker accepts either a symbol name or an address.\n",
                    "flag": "-e"
                },
                {
                    "name": "-pie",
                    "content": "Produce a dynamically linked position independent executable on targets that support  it.\nFor  predictable  results,  you  must  also  specify  the  same  set  of options used for\ncompilation (-fpie, -fPIE, or model suboptions) when you specify this linker option.\n"
                },
                {
                    "name": "-no-pie",
                    "content": "Don't produce a dynamically linked position independent executable.\n"
                },
                {
                    "name": "-static-pie",
                    "content": "Produce a static position independent executable on targets that support  it.   A  static\nposition  independent  executable is similar to a static executable, but can be loaded at\nany address without a dynamic linker.  For predictable results, you must also specify the\nsame set of options used for compilation (-fpie, -fPIE, or  model  suboptions)  when  you\nspecify this linker option.\n"
                },
                {
                    "name": "-pthread",
                    "content": "Link with the POSIX threads library.  This option is supported on GNU/Linux targets, most\nother  Unix  derivatives, and also on x86 Cygwin and MinGW targets.  On some targets this\noption also sets flags for the preprocessor, so it should be used consistently  for  both\ncompilation and linking.\n"
                },
                {
                    "name": "-r",
                    "content": "",
                    "flag": "-r"
                },
                {
                    "name": "-rdynamic",
                    "content": "Pass  the  flag  -export-dynamic  to  the  ELF  linker,  on targets that support it. This\ninstructs the linker to add all symbols, not only used ones, to the dynamic symbol table.\nThis option is needed for some uses of \"dlopen\" or to  allow  obtaining  backtraces  from\nwithin a program.\n"
                },
                {
                    "name": "-s",
                    "content": "",
                    "flag": "-s"
                },
                {
                    "name": "-static",
                    "content": "On  systems  that  support dynamic linking, this overrides -pie and prevents linking with\nthe shared libraries.  On other systems, this option has no effect.\n"
                },
                {
                    "name": "-shared",
                    "content": "Produce a shared object  which  can  then  be  linked  with  other  objects  to  form  an\nexecutable.  Not all systems support this option.  For predictable results, you must also\nspecify  the same set of options used for compilation (-fpic, -fPIC, or model suboptions)\nwhen you specify this linker option.[1]\n"
                },
                {
                    "name": "-shared-libgcc",
                    "content": ""
                },
                {
                    "name": "-static-libgcc",
                    "content": "On systems that provide libgcc as a shared library, these options force the use of either\nthe shared or static version, respectively.  If no shared version  of  libgcc  was  built\nwhen the compiler was configured, these options have no effect.\n\nThere are several situations in which an application should use the shared libgcc instead\nof  the static version.  The most common of these is when the application wishes to throw\nand catch exceptions across different shared  libraries.   In  that  case,  each  of  the\nlibraries as well as the application itself should use the shared libgcc.\n\nTherefore,  the  G++ driver automatically adds -shared-libgcc whenever you build a shared\nlibrary or a main executable, because C++ programs typically use exceptions, so  this  is\nthe right thing to do.\n\nIf,  instead,  you  use the GCC driver to create shared libraries, you may find that they\nare not always linked with the shared libgcc.  If GCC finds, at its  configuration  time,\nthat  you  have  a  non-GNU  linker  or  a  GNU  linker  that  does  not  support  option\n--eh-frame-hdr, it links the shared version of libgcc into shared libraries  by  default.\nOtherwise,  it  takes  advantage  of  the  linker and optimizes away the linking with the\nshared version of libgcc, linking with the static version of  libgcc  by  default.   This\nallows   exceptions  to  propagate  through  such  shared  libraries,  without  incurring\nrelocation costs at library load time.\n\nHowever, if a library or main executable is supposed to throw or  catch  exceptions,  you\nmust  link  it  using the G++ driver, or using the option -shared-libgcc, such that it is\nlinked with the shared libgcc.\n"
                },
                {
                    "name": "-static-libasan",
                    "content": "When  the  -fsanitize=address  option  is  used  to  link  a  program,  the  GCC   driver\nautomatically  links  against  libasan.  If libasan is available as a shared library, and\nthe -static option is not used, then this links against the shared  version  of  libasan.\nThe  -static-libasan  option  directs  the GCC driver to link libasan statically, without\nnecessarily linking other libraries statically.\n"
                },
                {
                    "name": "-static-libtsan",
                    "content": "When the -fsanitize=thread option is used to link a program, the GCC driver automatically\nlinks against libtsan.  If libtsan is available as a  shared  library,  and  the  -static\noption  is  not  used,  then  this  links  against  the  shared  version of libtsan.  The\n-static-libtsan option directs  the  GCC  driver  to  link  libtsan  statically,  without\nnecessarily linking other libraries statically.\n"
                },
                {
                    "name": "-static-liblsan",
                    "content": "When  the  -fsanitize=leak option is used to link a program, the GCC driver automatically\nlinks against liblsan.  If liblsan is available as a  shared  library,  and  the  -static\noption  is  not  used,  then  this  links  against  the  shared  version of liblsan.  The\n-static-liblsan option directs  the  GCC  driver  to  link  liblsan  statically,  without\nnecessarily linking other libraries statically.\n"
                },
                {
                    "name": "-static-libubsan",
                    "content": "When  the  -fsanitize=undefined  option  is  used  to  link  a  program,  the  GCC driver\nautomatically links against libubsan.  If libubsan is available as a shared library,  and\nthe  -static  option is not used, then this links against the shared version of libubsan.\nThe -static-libubsan option directs the GCC driver to link libubsan  statically,  without\nnecessarily linking other libraries statically.\n"
                },
                {
                    "name": "-static-libstdc++",
                    "content": "When  the  g++  program  is  used  to link a C++ program, it normally automatically links\nagainst libstdc++.  If libstdc++ is available as a shared library, and the -static option\nis not used, then this links against the shared version of libstdc++.  That  is  normally\nfine.   However,  it  is  sometimes useful to freeze the version of libstdc++ used by the\nprogram without going all the way to a fully static link.  The  -static-libstdc++  option\ndirects  the  g++  driver to link libstdc++ statically, without necessarily linking other\nlibraries statically.\n"
                },
                {
                    "name": "-symbolic",
                    "content": "Bind references to global  symbols  when  building  a  shared  object.   Warn  about  any\nunresolved  references  (unless overridden by the link editor option -Xlinker -z -Xlinker\ndefs).  Only a few systems support this option.\n"
                },
                {
                    "name": "-T _",
                    "content": "Use script as the linker script.  This option is supported by most systems using the  GNU\nlinker.   On some targets, such as bare-board targets without an operating system, the -T\noption may be required when linking to avoid references to undefined symbols.\n",
                    "flag": "-T"
                },
                {
                    "name": "-Xlinker _",
                    "content": "Pass option as an option to the linker.  You  can  use  this  to  supply  system-specific\nlinker options that GCC does not recognize.\n\nIf  you  want  to  pass  an  option that takes a separate argument, you must use -Xlinker\ntwice, once for the option and once for the  argument.   For  example,  to  pass  -assert\ndefinitions,  you  must write -Xlinker -assert -Xlinker definitions.  It does not work to\nwrite -Xlinker \"-assert definitions\", because this passes the entire string as  a  single\nargument, which is not what the linker expects.\n\nWhen  using  the  GNU  linker,  it is usually more convenient to pass arguments to linker\noptions using the option=value syntax than as separate arguments.  For example,  you  can\nspecify  -Xlinker  -Map=output.map  rather than -Xlinker -Map -Xlinker output.map.  Other\nlinkers may not support this syntax for command-line options.\n"
                },
                {
                    "name": "-Wl,_",
                    "content": "Pass option as an option to the linker.  If option contains  commas,  it  is  split  into\nmultiple  options  at  the  commas.   You  can use this syntax to pass an argument to the\noption.  For example, -Wl,-Map,output.map passes -Map output.map  to  the  linker.   When\nusing the GNU linker, you can also get the same effect with -Wl,-Map=output.map.\n\nNOTE:  In  Ubuntu  8.10 and later versions, for LDFLAGS, the option -Wl,-z,relro is used.\nTo disable, use -Wl,-z,norelro.\n"
                },
                {
                    "name": "-u _",
                    "content": "Pretend the symbol symbol is undefined, to force linking of library modules to define it.\nYou can use -u multiple times with different  symbols  to  force  loading  of  additional\nlibrary modules.\n",
                    "flag": "-u"
                },
                {
                    "name": "-z _",
                    "content": "-z is passed directly on to the linker along with the keyword keyword. See the section in\nthe documentation of your linker for permitted values and their meanings.\n",
                    "flag": "-z"
                },
                {
                    "name": "Options for Directory Search",
                    "content": "These  options specify directories to search for header files, for libraries and for parts of\nthe compiler:\n"
                },
                {
                    "name": "-I _",
                    "content": "",
                    "flag": "-I"
                },
                {
                    "name": "-iquote _",
                    "content": ""
                },
                {
                    "name": "-isystem _",
                    "content": ""
                },
                {
                    "name": "-idirafter _",
                    "content": "Add the directory dir to the list of directories to be searched for header  files  during\npreprocessing.   If  dir begins with = or $SYSROOT, then the = or $SYSROOT is replaced by\nthe sysroot prefix; see --sysroot and -isysroot.\n\nDirectories specified with -iquote apply  only  to  the  quote  form  of  the  directive,\n\"#include \"file\"\".   Directories  specified  with  -I,  -isystem,  or -idirafter apply to\nlookup for both the \"#include \"file\"\" and \"#include <file>\" directives.\n\nYou can specify any number or combination of these options on the command line to  search\nfor header files in several directories.  The lookup order is as follows:\n\n1.  For  the  quote  form  of the include directive, the directory of the current file is\nsearched first.\n\n2.  For the quote form of the include directive, the  directories  specified  by  -iquote\noptions are searched in left-to-right order, as they appear on the command line.\n\n3.  Directories specified with -I options are scanned in left-to-right order.\n\n4.  Directories specified with -isystem options are scanned in left-to-right order.\n\n5.  Standard system directories are scanned.\n\n6.  Directories specified with -idirafter options are scanned in left-to-right order.\n\nYou  can  use  -I  to override a system header file, substituting your own version, since\nthese directories are searched  before  the  standard  system  header  file  directories.\nHowever,  you  should not use this option to add directories that contain vendor-supplied\nsystem header files; use -isystem for that.\n\nThe -isystem and -idirafter options also mark the directory as  a  system  directory,  so\nthat  it  gets  the  same  special  treatment  that  is  applied  to  the standard system\ndirectories.\n\nIf a standard system include directory, or a directory specified with -isystem,  is  also\nspecified  with  -I,  the -I option is ignored.  The directory is still searched but as a\nsystem directory at its normal position in the system include chain.  This is  to  ensure\nthat GCC's procedure to fix buggy system headers and the ordering for the \"#includenext\"\ndirective  are  not inadvertently changed.  If you really need to change the search order\nfor system directories, use the -nostdinc and/or -isystem options.\n"
                },
                {
                    "name": "-I-  -iquote",
                    "content": "-I directories before the -I- and remove the -I- option.\n\nAny directories specified with -I options  before  -I-  are  searched  only  for  headers\nrequested  with  \"#include \"file\"\";  they  are  not  searched  for \"#include <file>\".  If\nadditional directories are specified with -I options after the -I-, those directories are\nsearched for all #include directives.\n\nIn addition, -I- inhibits the use of the directory of the current file directory  as  the\nfirst search directory for \"#include \"file\"\".  There is no way to override this effect of\n-I-.\n"
                },
                {
                    "name": "-iprefix _",
                    "content": "Specify  prefix  as  the  prefix  for  subsequent  -iwithprefix  options.   If the prefix\nrepresents a directory, you should include the final /.\n"
                },
                {
                    "name": "-iwithprefix _",
                    "content": ""
                },
                {
                    "name": "-iwithprefixbefore _",
                    "content": "Append dir to the prefix specified  previously  with  -iprefix,  and  add  the  resulting\ndirectory  to  the  include search path.  -iwithprefixbefore puts it in the same place -I\nwould; -iwithprefix puts it where -idirafter would.\n"
                },
                {
                    "name": "-isysroot _",
                    "content": "This option is like the --sysroot option, but applies only to header  files  (except  for\nDarwin  targets, where it applies to both header files and libraries).  See the --sysroot\noption for more information.\n"
                },
                {
                    "name": "-imultilib _",
                    "content": "Use dir as a subdirectory of the directory containing target-specific C++ headers.\n"
                },
                {
                    "name": "-nostdinc",
                    "content": "Do not search the standard system directories for header  files.   Only  the  directories\nexplicitly  specified  with  -I,  -iquote,  -isystem,  and/or -idirafter options (and the\ndirectory of the current file, if appropriate) are searched.\n"
                },
                {
                    "name": "-nostdinc++",
                    "content": "Do not search for header files in the C++-specific standard  directories,  but  do  still\nsearch  the  other  standard  directories.   (This  option  is used when building the C++\nlibrary.)\n"
                },
                {
                    "name": "-iplugindir=_",
                    "content": "Set the directory to search for plugins that  are  passed  by  -fplugin=name  instead  of\n-fplugin=path/name.so.   This option is not meant to be used by the user, but only passed\nby the driver.\n"
                },
                {
                    "name": "-L_",
                    "content": "Add directory dir to the list of directories to be searched for -l.\n"
                },
                {
                    "name": "-B_",
                    "content": "This option specifies where to find the executables, libraries, include files,  and  data\nfiles of the compiler itself.\n\nThe  compiler driver program runs one or more of the subprograms cpp, cc1, as and ld.  It\ntries prefix as a prefix for each  program  it  tries  to  run,  both  with  and  without\nmachine/version/ for the corresponding target machine and compiler version.\n\nFor each subprogram to be run, the compiler driver first tries the -B prefix, if any.  If\nthat  name  is  not  found,  or  if  -B  is  not specified, the driver tries two standard\nprefixes, /usr/lib/gcc/ and /usr/local/lib/gcc/.  If neither of those results in  a  file\nname  that  is  found,  the unmodified program name is searched for using the directories\nspecified in your PATH environment variable.\n\nThe compiler checks to see if the path provided by -B  refers  to  a  directory,  and  if\nnecessary it adds a directory separator character at the end of the path.\n\n-B  prefixes  that  effectively  specify  directory  names also apply to libraries in the\nlinker, because the compiler translates these options into -L  options  for  the  linker.\nThey  also  apply  to  include files in the preprocessor, because the compiler translates\nthese options into -isystem options for the preprocessor.  In  this  case,  the  compiler\nappends include to the prefix.\n\nThe  runtime  support  file  libgcc.a  can  also  be searched for using the -B prefix, if\nneeded.  If it is not found there, the two standard prefixes above are tried, and that is\nall.  The file is left out of the link if it is not found by those means.\n\nAnother way to specify a prefix much like  the  -B  prefix  is  to  use  the  environment\nvariable GCCEXECPREFIX.\n\nAs  a special kludge, if the path provided by -B is [dir/]stageN/, where N is a number in\nthe range 0 to 9, then it is replaced by [dir/]include.   This  is  to  help  with  boot-\nstrapping the compiler.\n"
                },
                {
                    "name": "-no-canonical-prefixes",
                    "content": "Do  not  expand  any  symbolic links, resolve references to /../ or /./, or make the path\nabsolute when generating a relative prefix.\n\n--sysroot=dir\nUse dir as the logical root directory for headers and libraries.   For  example,  if  the\ncompiler  normally  searches  for  headers  in /usr/include and libraries in /usr/lib, it\ninstead searches dir/usr/include and dir/usr/lib.\n\nIf you use both this option and the -isysroot option, then the --sysroot  option  applies\nto libraries, but the -isysroot option applies to header files.\n\nThe  GNU  linker (beginning with version 2.16) has the necessary support for this option.\nIf your linker does not support this option, the header file aspect  of  --sysroot  still\nworks, but the library aspect does not.\n"
                },
                {
                    "name": "--no-sysroot-suffix",
                    "content": "For  some  targets,  a  suffix  is  added to the root directory specified with --sysroot,\ndepending on the other options used,  so  that  headers  may  for  example  be  found  in\ndir/suffix/usr/include  instead of dir/usr/include.  This option disables the addition of\nsuch a suffix.\n",
                    "long": "--no-sysroot-suffix"
                },
                {
                    "name": "Options for Code Generation Conventions",
                    "content": "These machine-independent options control the interface conventions used in code generation.\n\nMost of them have both positive and negative forms; the negative form of -ffoo  is  -fno-foo.\nIn  the  table below, only one of the forms is listed---the one that is not the default.  You\ncan figure out the other form by either removing no- or adding it.\n"
                },
                {
                    "name": "-fstack-reuse=_",
                    "content": "This option controls stack  space  reuse  for  user  declared  local/auto  variables  and\ncompiler generated temporaries.  reuselevel can be all, namedvars, or none. all enables\nstack  reuse  for  all local variables and temporaries, namedvars enables the reuse only\nfor user defined local variables with names, and none disables  stack  reuse  completely.\nThe default value is all. The option is needed when the program extends the lifetime of a\nscoped  local  variable or a compiler generated temporary beyond the end point defined by\nthe language.  When a lifetime of a variable ends, and if the variable lives  in  memory,\nthe  optimizing  compiler has the freedom to reuse its stack space with other temporaries\nor scoped local variables whose  live  range  does  not  overlap  with  it.  Legacy  code\nextending local lifetime is likely to break with the stack reuse optimization.\n\nFor example,\n\nint *p;\n{\nint local1;\n\np = &local1;\nlocal1 = 10;\n....\n}\n{\nint local2;\nlocal2 = 20;\n...\n}\n\nif (*p == 10)  // out of scope use of local1\n{\n\n}\n\nAnother example:\n\nstruct A\n{\nA(int k) : i(k), j(k) { }\nint i;\nint j;\n};\n\nA *ap;\n\nvoid foo(const A& ar)\n{\nap = &ar;\n}\n\nvoid bar()\n{\nfoo(A(10)); // temp object's lifetime ends when foo returns\n\n{\nA a(20);\n....\n}\nap->i+= 10;  // ap references out of scope temp whose space\n// is reused with a. What is the value of ap->i?\n}\n\nThe  lifetime of a compiler generated temporary is well defined by the C++ standard. When\na lifetime of a temporary ends, and if the temporary  lives  in  memory,  the  optimizing\ncompiler  has the freedom to reuse its stack space with other temporaries or scoped local\nvariables whose live range does not overlap with it. However  some  of  the  legacy  code\nrelies  on  the  behavior  of  older  compilers  in which temporaries' stack space is not\nreused, the aggressive stack reuse can lead to runtime errors. This  option  is  used  to\ncontrol the temporary stack reuse optimization.\n"
                },
                {
                    "name": "-ftrapv",
                    "content": "This  option generates traps for signed overflow on addition, subtraction, multiplication\noperations.  The options -ftrapv and  -fwrapv  override  each  other,  so  using  -ftrapv\n-fwrapv  on  the  command-line results in -fwrapv being effective.  Note that only active\noptions override, so using -ftrapv -fwrapv -fno-wrapv  on  the  command-line  results  in\n-ftrapv being effective.\n"
                },
                {
                    "name": "-fwrapv",
                    "content": "This option instructs the compiler to assume that signed arithmetic overflow of addition,\nsubtraction  and  multiplication wraps around using twos-complement representation.  This\nflag enables some optimizations and disables others.  The  options  -ftrapv  and  -fwrapv\noverride  each  other,  so  using  -ftrapv -fwrapv on the command-line results in -fwrapv\nbeing effective.  Note that only  active  options  override,  so  using  -ftrapv  -fwrapv\n-fno-wrapv on the command-line results in -ftrapv being effective.\n"
                },
                {
                    "name": "-fwrapv-pointer",
                    "content": "This option instructs the compiler to assume that pointer arithmetic overflow on addition\nand  subtraction  wraps  around using twos-complement representation.  This flag disables\nsome optimizations which assume pointer overflow is invalid.\n"
                },
                {
                    "name": "-fstrict-overflow",
                    "content": "This option implies  -fno-wrapv  -fno-wrapv-pointer  and  when  negated  implies  -fwrapv\n-fwrapv-pointer.\n"
                },
                {
                    "name": "-fexceptions",
                    "content": "Enable  exception  handling.   Generates  extra code needed to propagate exceptions.  For\nsome targets, this implies GCC generates frame  unwind  information  for  all  functions,\nwhich  can produce significant data size overhead, although it does not affect execution.\nIf you do not specify this option, GCC enables it by default for languages like C++  that\nnormally  require  exception  handling,  and disables it for languages like C that do not\nnormally require it.  However, you may need to enable this option when compiling  C  code\nthat needs to interoperate properly with exception handlers written in C++.  You may also\nwish  to  disable  this  option  if  you  are compiling older C++ programs that don't use\nexception handling.\n"
                },
                {
                    "name": "-fnon-call-exceptions",
                    "content": "Generate code that allows trapping instructions to  throw  exceptions.   Note  that  this\nrequires  platform-specific runtime support that does not exist everywhere.  Moreover, it\nonly allows  trapping  instructions  to  throw  exceptions,  i.e.  memory  references  or\nfloating-point  instructions.   It  does not allow exceptions to be thrown from arbitrary\nsignal handlers such as \"SIGALRM\".  This enables -fexceptions.\n"
                },
                {
                    "name": "-fdelete-dead-exceptions",
                    "content": "Consider that instructions that may throw exceptions but don't  otherwise  contribute  to\nthe  execution  of  the  program  can  be  optimized away.  This does not affect calls to\nfunctions except those with the \"pure\" or \"const\" attributes.  This option is enabled  by\ndefault  for  the  Ada  and  C++  compilers, as permitted by the language specifications.\nOptimization passes that cause dead exceptions to be removed are enabled independently at\ndifferent optimization levels.\n"
                },
                {
                    "name": "-funwind-tables",
                    "content": "Similar to -fexceptions, except that it just generates any needed static data,  but  does\nnot  affect the generated code in any other way.  You normally do not need to enable this\noption; instead, a language processor that needs this handling enables it on your behalf.\n"
                },
                {
                    "name": "-fasynchronous-unwind-tables",
                    "content": "Generate unwind table in DWARF format, if supported by  target  machine.   The  table  is\nexact  at  each  instruction  boundary,  so  it  can  be  used  for  stack unwinding from\nasynchronous events (such as debugger or garbage collector).\n"
                },
                {
                    "name": "-fno-gnu-unique",
                    "content": "On systems  with  recent  GNU  assembler  and  C  library,  the  C++  compiler  uses  the\n\"STBGNUUNIQUE\"  binding  to  make sure that definitions of template static data members\nand static local variables in inline  functions  are  unique  even  in  the  presence  of\n\"RTLDLOCAL\";  this  is  necessary to avoid problems with a library used by two different\n\"RTLDLOCAL\" plugins depending on a definition in one of them and  therefore  disagreeing\nwith  the  other  one  about  the binding of the symbol.  But this causes \"dlclose\" to be\nignored for affected DSOs; if your program  relies  on  reinitialization  of  a  DSO  via\n\"dlclose\" and \"dlopen\", you can use -fno-gnu-unique.\n"
                },
                {
                    "name": "-fpcc-struct-return",
                    "content": "Return  \"short\"  \"struct\"  and  \"union\" values in memory like longer ones, rather than in\nregisters.  This convention is less efficient, but  it  has  the  advantage  of  allowing\nintercallability  between  GCC-compiled  files  and  files compiled with other compilers,\nparticularly the Portable C Compiler (pcc).\n\nThe precise  convention  for  returning  structures  in  memory  depends  on  the  target\nconfiguration macros.\n\nShort structures and unions are those whose size and alignment match that of some integer\ntype.\n\nWarning:  code compiled with the -fpcc-struct-return switch is not binary compatible with\ncode compiled with the -freg-struct-return switch.  Use it to conform  to  a  non-default\napplication binary interface.\n"
                },
                {
                    "name": "-freg-struct-return",
                    "content": "Return  \"struct\"  and  \"union\" values in registers when possible.  This is more efficient\nfor small structures than -fpcc-struct-return.\n\nIf you specify neither  -fpcc-struct-return  nor  -freg-struct-return,  GCC  defaults  to\nwhichever convention is standard for the target.  If there is no standard convention, GCC\ndefaults  to  -fpcc-struct-return, except on targets where GCC is the principal compiler.\nIn those cases, we can choose the standard, and we  chose  the  more  efficient  register\nreturn alternative.\n\nWarning:  code compiled with the -freg-struct-return switch is not binary compatible with\ncode compiled with the -fpcc-struct-return switch.  Use it to conform  to  a  non-default\napplication binary interface.\n"
                },
                {
                    "name": "-fshort-enums",
                    "content": "Allocate  to  an  \"enum\"  type  only  as many bytes as it needs for the declared range of\npossible values.  Specifically, the \"enum\" type is equivalent  to  the  smallest  integer\ntype that has enough room.\n\nWarning:  the  -fshort-enums  switch  causes  GCC  to  generate  code  that is not binary\ncompatible with code generated without that switch.  Use it to conform to  a  non-default\napplication binary interface.\n"
                },
                {
                    "name": "-fshort-wchar",
                    "content": "Override  the  underlying  type  for  \"wchart\" to be \"short unsigned int\" instead of the\ndefault for the target.  This option is useful for building programs to run under WINE.\n\nWarning: the -fshort-wchar switch  causes  GCC  to  generate  code  that  is  not  binary\ncompatible  with  code generated without that switch.  Use it to conform to a non-default\napplication binary interface.\n"
                },
                {
                    "name": "-fcommon",
                    "content": "In C code, this option controls the placement of  global  variables  defined  without  an\ninitializer, known as tentative definitions in the C standard.  Tentative definitions are\ndistinct from declarations of a variable with the \"extern\" keyword, which do not allocate\nstorage.\n\nThe default is -fno-common, which specifies that the compiler places uninitialized global\nvariables  in the BSS section of the object file.  This inhibits the merging of tentative\ndefinitions by the linker so you get a multiple-definition error if the same variable  is\naccidentally defined in more than one compilation unit.\n\nThe  -fcommon  places  uninitialized global variables in a common block.  This allows the\nlinker to resolve all tentative definitions of the same variable in different compilation\nunits  to  the  same  object,  or  to  a  non-tentative  definition.   This  behavior  is\ninconsistent  with  C++,  and  on  many  targets implies a speed and code size penalty on\nglobal variable references.  It is mainly useful to enable legacy code  to  link  without\nerrors.\n"
                },
                {
                    "name": "-fno-ident",
                    "content": "Ignore the \"#ident\" directive.\n"
                },
                {
                    "name": "-finhibit-size-directive",
                    "content": "Don't  output a \".size\" assembler directive, or anything else that would cause trouble if\nthe function is split in the middle, and the two halves are placed at locations far apart\nin memory.  This option is used when compiling crtstuff.c; you should not need to use  it\nfor anything else.\n"
                },
                {
                    "name": "-fverbose-asm",
                    "content": "Put extra commentary information in the generated assembly code to make it more readable.\nThis  option  is  generally  only of use to those who actually need to read the generated\nassembly code (perhaps while debugging the compiler itself).\n\n-fno-verbose-asm, the default, causes the extra information to be omitted and  is  useful\nwhen comparing two assembler files.\n\nThe added comments include:\n\n*   information on the compiler version and command-line options,\n\n*   the  source  code  lines  associated  with  the  assembly  instructions,  in the form\nFILENAME:LINENUMBER:CONTENT OF LINE,\n\n*   hints on which high-level expressions correspond to the various assembly  instruction\noperands.\n\nFor example, given this C source file:\n\nint test (int n)\n{\nint i;\nint total = 0;\n\nfor (i = 0; i < n; i++)\ntotal += i * i;\n\nreturn total;\n}\n\ncompiling to (x8664) assembly via -S and emitting the result direct to stdout via -o -\n\ngcc -S test.c -fverbose-asm -Os -o -\n\ngives output similar to this:\n\n.file   \"test.c\"\n# GNU C11 (GCC) version 7.0.0 20160809 (experimental) (x8664-pc-linux-gnu)\n[...snip...]\n# options passed:\n[...snip...]\n\n.text\n.globl  test\n.type   test, @function\ntest:\n.LFB0:\n.cfistartproc\n# test.c:4:   int total = 0;\nxorl    %eax, %eax      # <retval>\n# test.c:6:   for (i = 0; i < n; i++)\nxorl    %edx, %edx      # i\n.L2:\n# test.c:6:   for (i = 0; i < n; i++)\ncmpl    %edi, %edx      # n, i\njge     .L5     #,\n# test.c:7:     total += i * i;\nmovl    %edx, %ecx      # i, tmp92\nimull   %edx, %ecx      # i, tmp92\n# test.c:6:   for (i = 0; i < n; i++)\nincl    %edx    # i\n# test.c:7:     total += i * i;\naddl    %ecx, %eax      # tmp92, <retval>\njmp     .L2     #\n.L5:\n# test.c:10: }\nret\n.cfiendproc\n.LFE0:\n.size   test, .-test\n.ident  \"GCC: (GNU) 7.0.0 20160809 (experimental)\"\n.section        .note.GNU-stack,\"\",@progbits\n\nThe comments are intended for humans rather than machines and hence the precise format of\nthe comments is subject to change.\n"
                },
                {
                    "name": "-frecord-gcc-switches",
                    "content": "This  switch  causes the command line used to invoke the compiler to be recorded into the\nobject file that is being created.  This switch is only implemented on some  targets  and\nthe  exact  format  of  the  recording is target and binary file format dependent, but it\nusually takes the form of a section containing ASCII text.  This switch is related to the\n-fverbose-asm switch, but that switch only records information in  the  assembler  output\nfile  as  comments,  so it never reaches the object file.  See also -grecord-gcc-switches\nfor another way of storing compiler options into the object file.\n"
                },
                {
                    "name": "-fpic",
                    "content": "Generate position-independent code (PIC)  suitable  for  use  in  a  shared  library,  if\nsupported  for  the  target machine.  Such code accesses all constant addresses through a\nglobal offset table (GOT).  The dynamic loader resolves the GOT entries when the  program\nstarts  (the  dynamic loader is not part of GCC; it is part of the operating system).  If\nthe GOT size for the linked executable exceeds a machine-specific maximum size,  you  get\nan  error  message  from  the  linker  indicating that -fpic does not work; in that case,\nrecompile with -fPIC instead.  (These maximums are 8k on the SPARC, 28k  on  AArch64  and\n32k on the m68k and RS/6000.  The x86 has no such limit.)\n\nPosition-independent  code  requires special support, and therefore works only on certain\nmachines.  For the x86, GCC supports PIC for System V but not for  the  Sun  386i.   Code\ngenerated for the IBM RS/6000 is always position-independent.\n\nWhen this flag is set, the macros \"pic\" and \"PIC\" are defined to 1.\n"
                },
                {
                    "name": "-fPIC",
                    "content": "If supported for the target machine, emit position-independent code, suitable for dynamic\nlinking and avoiding any limit on the size of the global offset table.  This option makes\na difference on AArch64, m68k, PowerPC and SPARC.\n\nPosition-independent  code  requires special support, and therefore works only on certain\nmachines.\n\nWhen this flag is set, the macros \"pic\" and \"PIC\" are defined to 2.\n"
                },
                {
                    "name": "-fpie",
                    "content": ""
                },
                {
                    "name": "-fPIE",
                    "content": "These options are similar to -fpic and -fPIC, but the generated position-independent code\ncan be only linked into executables.  Usually these options are used to compile code that\nwill be linked using the -pie GCC option.\n\n-fpie and -fPIE both define the macros \"pie\" and  \"PIE\".   The  macros  have  the\nvalue 1 for -fpie and 2 for -fPIE.\n"
                },
                {
                    "name": "-fno-plt",
                    "content": "Do  not  use  the PLT for external function calls in position-independent code.  Instead,\nload the callee address at call sites from the GOT and branch to it.  This leads to  more\nefficient  code  by  eliminating  PLT  stubs and exposing GOT loads to optimizations.  On\narchitectures such as 32-bit x86 where PLT stubs expect the GOT  pointer  in  a  specific\nregister,  this  gives  more  register  allocation freedom to the compiler.  Lazy binding\nrequires use of the PLT; with -fno-plt all external symbols are resolved at load time.\n\nAlternatively, the function attribute \"noplt\" can be used to avoid calls through the  PLT\nfor specific external functions.\n\nIn position-dependent code, a few targets also convert calls to functions that are marked\nto not use the PLT to use the GOT instead.\n"
                },
                {
                    "name": "-fno-jump-tables",
                    "content": "Do  not  use jump tables for switch statements even where it would be more efficient than\nother code generation strategies.  This option is of use in  conjunction  with  -fpic  or\n-fPIC  for  building  code  that  forms part of a dynamic linker and cannot reference the\naddress of a jump table.  On some targets, jump tables do not  require  a  GOT  and  this\noption is not needed.\n"
                },
                {
                    "name": "-fno-bit-tests",
                    "content": "Do  not  use  bit  tests for switch statements even where it would be more efficient than\nother code generation strategies.\n"
                },
                {
                    "name": "-ffixed-_",
                    "content": "Treat the register named reg as a fixed register; generated code should never refer to it\n(except perhaps as a stack pointer, frame pointer or in some other fixed role).\n\nreg must be the name of a register.  The register names accepted are machine-specific and\nare defined in the \"REGISTERNAMES\" macro in the machine description macro file.\n\nThis flag does not have a negative form, because it specifies a three-way choice.\n"
                },
                {
                    "name": "-fcall-used-_",
                    "content": "Treat the register named reg as an allocable  register  that  is  clobbered  by  function\ncalls.   It may be allocated for temporaries or variables that do not live across a call.\nFunctions compiled this way do not save and restore the register reg.\n\nIt is an error to use this flag with the frame pointer or stack  pointer.   Use  of  this\nflag for other registers that have fixed pervasive roles in the machine's execution model\nproduces disastrous results.\n\nThis flag does not have a negative form, because it specifies a three-way choice.\n"
                },
                {
                    "name": "-fcall-saved-_",
                    "content": "Treat  the  register  named  reg  as an allocable register saved by functions.  It may be\nallocated even for temporaries or variables that live across a call.  Functions  compiled\nthis way save and restore the register reg if they use it.\n\nIt  is  an  error  to use this flag with the frame pointer or stack pointer.  Use of this\nflag for other registers that have fixed pervasive roles in the machine's execution model\nproduces disastrous results.\n\nA different sort of disaster results from the use of this flag for a  register  in  which\nfunction values may be returned.\n\nThis flag does not have a negative form, because it specifies a three-way choice.\n"
                },
                {
                    "name": "-fpack-struct[=_",
                    "content": "Without  a  value  specified,  pack all structure members together without holes.  When a\nvalue is specified (which must be a small power of two), pack structure members according\nto this value,  representing  the  maximum  alignment  (that  is,  objects  with  default\nalignment  requirements  larger  than  this  are output potentially unaligned at the next\nfitting location.\n\nWarning: the -fpack-struct switch  causes  GCC  to  generate  code  that  is  not  binary\ncompatible  with  code  generated  without  that switch.  Additionally, it makes the code\nsuboptimal.  Use it to conform to a non-default application binary interface.\n"
                },
                {
                    "name": "-fleading-underscore",
                    "content": "This option and its counterpart,  -fno-leading-underscore,  forcibly  change  the  way  C\nsymbols are represented in the object file.  One use is to help link with legacy assembly\ncode.\n\nWarning:  the  -fleading-underscore switch causes GCC to generate code that is not binary\ncompatible with code generated without that switch.  Use it to conform to  a  non-default\napplication binary interface.  Not all targets provide complete support for this switch.\n"
                },
                {
                    "name": "-ftls-model=_",
                    "content": "Alter  the  thread-local  storage  model to be used.  The model argument should be one of\nglobal-dynamic, local-dynamic, initial-exec or  local-exec.   Note  that  the  choice  is\nsubject  to  optimization:  the  compiler  may use a more efficient model for symbols not\nvisible outside of the translation unit, or if -fpic is not given on the command line.\n\nThe default without -fpic is initial-exec; with -fpic the default is global-dynamic.\n"
                },
                {
                    "name": "-ftrampolines",
                    "content": "For targets that normally need trampolines for nested  functions,  always  generate  them\ninstead  of  using  descriptors.   Otherwise, for targets that do not need them, like for\nexample HP-PA or IA-64, do nothing.\n\nA trampoline is a small piece of code that is created at run time on the stack  when  the\naddress  of  a  nested  function  is  taken,  and  is  used  to  call the nested function\nindirectly.  Therefore, it requires the stack to be made  executable  in  order  for  the\nprogram to work properly.\n\n-fno-trampolines  is  enabled  by  default  on  a  language  by language basis to let the\ncompiler avoid generating them, if it computes that this is safe, and replace  them  with\ndescriptors.   Descriptors  are  made  up  of  data  only, but the generated code must be\nprepared to deal with them.  As of this writing, -fno-trampolines is enabled  by  default\nonly for Ada.\n\nMoreover,  code  compiled  with -ftrampolines and code compiled with -fno-trampolines are\nnot binary compatible if nested functions are present.  This  option  must  therefore  be\nused on a program-wide basis and be manipulated with extreme care.\n\nFor  languages  other  than  Ada,  the  \"-ftrampolines\"  and  \"-fno-trampolines\"  options\ncurrently have no effect, and trampolines are always generated  on  platforms  that  need\nthem for nested functions.\n"
                },
                {
                    "name": "-fvisibility=",
                    "content": "Set  the  default  ELF  image symbol visibility to the specified option---all symbols are\nmarked with this unless  overridden  within  the  code.   Using  this  feature  can  very\nsubstantially  improve  linking  and  load times of shared object libraries, produce more\noptimized code, provide near-perfect API  export  and  prevent  symbol  clashes.   It  is\nstrongly recommended that you use this in any shared objects you distribute.\n\nDespite  the  nomenclature,  default  always  means  public; i.e., available to be linked\nagainst from outside the shared object.  protected and internal  are  pretty  useless  in\nreal-world  usage  so  the  only  other  commonly  used option is hidden.  The default if\n-fvisibility isn't specified is default, i.e., make every symbol public.\n\nA good explanation of the benefits offered by  ensuring  ELF  symbols  have  the  correct\nvisibility  is  given  by \"How To Write Shared Libraries\" by Ulrich Drepper (which can be\nfound at <https://www.akkadia.org/drepper/>)---however a superior solution made  possible\nby this option to marking things hidden when the default is public is to make the default\nhidden  and  mark  things  public.   This  is  the  norm  with  DLLs  on Windows and with\n-fvisibility=hidden   and   \"attribute    ((visibility(\"default\")))\"    instead    of\n\"declspec(dllexport)\"  you  get almost identical semantics with identical syntax.  This\nis a great boon to those working with cross-platform projects.\n\nFor those adding  visibility  support  to  existing  code,  you  may  find  \"#pragma  GCC\nvisibility\"  of  use.   This  works  by  you  enclosing  the declarations you wish to set\nvisibility for with (for example) \"#pragma GCC visibility push(hidden)\" and \"#pragma  GCC\nvisibility pop\".  Bear in mind that symbol visibility should be viewed as part of the API\ninterface  contract and thus all new code should always specify visibility when it is not\nthe default; i.e., declarations only for use within the local DSO should always be marked\nexplicitly as hidden as so to avoid PLT indirection  overheads---making  this  abundantly\nclear also aids readability and self-documentation of the code.  Note that due to ISO C++\nspecification  requirements,  \"operator  new\"  and  \"operator  delete\"  must always be of\ndefault visibility.\n\nBe aware that headers from outside your project, in particular system headers and headers\nfrom any other library you use, may not be expecting to be compiled with visibility other\nthan the default.  You may need to explicitly say \"#pragma GCC visibility  push(default)\"\nbefore including any such headers.\n\n\"extern\"  declarations  are  not  affected  by  -fvisibility,  so  a  lot  of code can be\nrecompiled with -fvisibility=hidden with no  modifications.   However,  this  means  that\ncalls  to  \"extern\"  functions  with  no  explicit  visibility use the PLT, so it is more\neffective to use \"attribute ((visibility))\" and/or \"#pragma GCC visibility\" to tell the\ncompiler which \"extern\" declarations should be treated as hidden.\n\nNote that -fvisibility does affect C++ vague  linkage  entities.  This  means  that,  for\ninstance,  an  exception  class  that is be thrown between DSOs must be explicitly marked\nwith default visibility so that the typeinfo nodes are unified between the DSOs.\n\nAn  overview  of  these  techniques,  their  benefits  and  how  to  use   them   is   at\n<https://gcc.gnu.org/wiki/Visibility>.\n"
                },
                {
                    "name": "-fstrict-volatile-bitfields",
                    "content": "This option should be used if accesses to volatile bit-fields (or other structure fields,\nalthough  the  compiler  usually honors those types anyway) should use a single access of\nthe width of the field's type, aligned to a natural alignment if possible.  For  example,\ntargets  with memory-mapped peripheral registers might require all such accesses to be 16\nbits wide; with this flag you can declare all peripheral bit-fields as  \"unsigned  short\"\n(assuming  short is 16 bits on these targets) to force GCC to use 16-bit accesses instead\nof, perhaps, a more efficient 32-bit access.\n\nIf this option is disabled, the compiler uses the most  efficient  instruction.   In  the\nprevious  example,  that  might  be  a 32-bit load instruction, even though that accesses\nbytes that do not contain any  portion  of  the  bit-field,  or  memory-mapped  registers\nunrelated to the one being updated.\n\nIn  some  cases,  such as when the \"packed\" attribute is applied to a structure field, it\nmay not be possible to access the field with a single read or  write  that  is  correctly\naligned  for  the  target  machine.   In  this case GCC falls back to generating multiple\naccesses rather than code that will fault or truncate the result at run time.\n\nNote:  Due to restrictions of the C/C++11 memory model, write accesses are not allowed to\ntouch non bit-field members.  It is therefore recommended  to  define  all  bits  of  the\nfield's type as bit-field members.\n\nThe  default  value  of this option is determined by the application binary interface for\nthe target processor.\n"
                },
                {
                    "name": "-fsync-libcalls",
                    "content": "This option controls whether any out-of-line instance of the \"sync\" family of functions\nmay be used to implement the C++11 \"atomic\" family of functions.\n\nThe default value of this option is enabled, thus the only useful form of the  option  is\n-fno-sync-libcalls.   This  option is used in the implementation of the libatomic runtime\nlibrary.\n"
                },
                {
                    "name": "GCC Developer Options",
                    "content": "This section describes command-line options that are primarily of interest to GCC developers,\nincluding options to support compiler testing and investigation of compiler bugs and compile-\ntime performance problems.  This includes options that produce debug dumps at various  points\nin  the  compilation;  that  print statistics such as memory use and execution time; and that\nprint information about GCC's configuration, such as where it searches  for  libraries.   You\nshould rarely need to use any of these options for ordinary compilation and linking tasks.\n\nMany  developer  options  that  cause GCC to dump output to a file take an optional =filename\nsuffix. You can specify stdout or - to dump to  standard  output,  and  stderr  for  standard\nerror.\n\nIf  =filename  is  omitted, a default dump file name is constructed by concatenating the base\ndump file name, a pass number, phase letter, and pass name.  The base dump file name  is  the\nname  of  output file produced by the compiler if explicitly specified and not an executable;\notherwise it is the source file name.  The pass number is determined by the order passes  are\nregistered  with  the  compiler's  pass  manager.  This is generally the same as the order of\nexecution, but passes registered by plugins,  target-specific  passes,  or  passes  that  are\notherwise  registered  late  are  numbered higher than the pass named final, even if they are\nexecuted earlier.  The phase letter is one of i  (inter-procedural  analysis),  l  (language-\nspecific), r (RTL), or t (tree).  The files are created in the directory of the output file.\n"
                },
                {
                    "name": "-fcallgraph-info",
                    "content": ""
                },
                {
                    "name": "-fcallgraph-info=_",
                    "content": "Makes  the  compiler  output  callgraph information for the program, on a per-object-file\nbasis.  The information is generated in the common VCG format.  It can be decorated  with\nadditional, per-node and/or per-edge information, if a list of comma-separated markers is\nadditionally  specified.   When  the \"su\" marker is specified, the callgraph is decorated\nwith stack usage information; it is equivalent to -fstack-usage.  When the \"da\" marker is\nspecified, the callgraph  is  decorated  with  information  about  dynamically  allocated\nobjects.\n\nWhen compiling with -flto, no callgraph information is output along with the object file.\nAt LTO link time, -fcallgraph-info may generate multiple callgraph information files next\nto intermediate LTO output files.\n"
                },
                {
                    "name": "-d_",
                    "content": ""
                },
                {
                    "name": "-fdump-rtl-_",
                    "content": ""
                },
                {
                    "name": "-fdump-rtl-_",
                    "content": "Says  to  make debugging dumps during compilation at times specified by letters.  This is\nused for debugging the RTL-based passes of the compiler.\n\nSome -dletters switches have different meaning when -E is used for preprocessing.\n\nDebug dumps can be enabled with a -fdump-rtl switch or some -d option letters.  Here  are\nthe possible letters for use in pass and letters, and their meanings:\n\n-fdump-rtl-alignments\nDump after branch alignments have been computed.\n\n-fdump-rtl-asmcons\nDump after fixing rtl statements that have unsatisfied in/out constraints.\n\n-fdump-rtl-autoincdec\nDump  after auto-inc-dec discovery.  This pass is only run on architectures that have\nauto inc or auto dec instructions.\n\n-fdump-rtl-barriers\nDump after cleaning up the barrier instructions.\n\n-fdump-rtl-bbpart\nDump after partitioning hot and cold basic blocks.\n\n-fdump-rtl-bbro\nDump after block reordering.\n\n-fdump-rtl-btl1\n-fdump-rtl-btl2\n-fdump-rtl-btl1 and -fdump-rtl-btl2 enable dumping after the two branch  target  load\noptimization passes.\n\n-fdump-rtl-bypass\nDump after jump bypassing and control flow optimizations.\n\n-fdump-rtl-combine\nDump after the RTL instruction combination pass.\n\n-fdump-rtl-compgotos\nDump after duplicating the computed gotos.\n\n-fdump-rtl-ce1\n-fdump-rtl-ce2\n-fdump-rtl-ce3\n-fdump-rtl-ce1,  -fdump-rtl-ce2, and -fdump-rtl-ce3 enable dumping after the three if\nconversion passes.\n\n-fdump-rtl-cprophardreg\nDump after hard register copy propagation.\n\n-fdump-rtl-csa\nDump after combining stack adjustments.\n\n-fdump-rtl-cse1\n-fdump-rtl-cse2\n-fdump-rtl-cse1 and -fdump-rtl-cse2 enable dumping after the two common subexpression\nelimination passes.\n\n-fdump-rtl-dce\nDump after the standalone dead code elimination passes.\n\n-fdump-rtl-dbr\nDump after delayed branch scheduling.\n\n-fdump-rtl-dce1\n-fdump-rtl-dce2\n-fdump-rtl-dce1  and  -fdump-rtl-dce2  enable  dumping  after  the  two  dead   store\nelimination passes.\n\n-fdump-rtl-eh\nDump after finalization of EH handling code.\n\n-fdump-rtl-ehranges\nDump after conversion of EH handling range regions.\n\n-fdump-rtl-expand\nDump after RTL generation.\n\n-fdump-rtl-fwprop1\n-fdump-rtl-fwprop2\n-fdump-rtl-fwprop1  and  -fdump-rtl-fwprop2  enable  dumping  after  the  two forward\npropagation passes.\n\n-fdump-rtl-gcse1\n-fdump-rtl-gcse2\n-fdump-rtl-gcse1  and   -fdump-rtl-gcse2   enable   dumping   after   global   common\nsubexpression elimination.\n\n-fdump-rtl-init-regs\nDump after the initialization of the registers.\n\n-fdump-rtl-initvals\nDump after the computation of the initial value sets.\n\n-fdump-rtl-intocfglayout\nDump after converting to cfglayout mode.\n\n-fdump-rtl-ira\nDump after iterated register allocation.\n\n-fdump-rtl-jump\nDump after the second jump optimization.\n\n-fdump-rtl-loop2\n-fdump-rtl-loop2 enables dumping after the rtl loop optimization passes.\n\n-fdump-rtl-mach\nDump after performing the machine dependent reorganization pass, if that pass exists.\n\n-fdump-rtl-modesw\nDump after removing redundant mode switches.\n\n-fdump-rtl-rnreg\nDump after register renumbering.\n\n-fdump-rtl-outofcfglayout\nDump after converting from cfglayout mode.\n\n-fdump-rtl-peephole2\nDump after the peephole pass.\n\n-fdump-rtl-postreload\nDump after post-reload optimizations.\n\n-fdump-rtl-proandepilogue\nDump after generating the function prologues and epilogues.\n\n-fdump-rtl-sched1\n-fdump-rtl-sched2\n-fdump-rtl-sched1   and  -fdump-rtl-sched2  enable  dumping  after  the  basic  block\nscheduling passes.\n\n-fdump-rtl-ree\nDump after sign/zero extension elimination.\n\n-fdump-rtl-seqabstr\nDump after common sequence discovery.\n\n-fdump-rtl-shorten\nDump after shortening branches.\n\n-fdump-rtl-sibling\nDump after sibling call optimizations.\n\n-fdump-rtl-split1\n-fdump-rtl-split2\n-fdump-rtl-split3\n-fdump-rtl-split4\n-fdump-rtl-split5\nThese options enable dumping after five rounds of instruction splitting.\n\n-fdump-rtl-sms\nDump after modulo scheduling.  This pass is only run on some architectures.\n\n-fdump-rtl-stack\nDump after conversion from GCC's \"flat register file\" registers to the  x87's  stack-\nlike registers.  This pass is only run on x86 variants.\n\n-fdump-rtl-subreg1\n-fdump-rtl-subreg2\n-fdump-rtl-subreg1  and  -fdump-rtl-subreg2  enable  dumping  after  the  two  subreg\nexpansion passes.\n\n-fdump-rtl-unshare\nDump after all rtl has been unshared.\n\n-fdump-rtl-vartrack\nDump after variable tracking.\n\n-fdump-rtl-vregs\nDump after converting virtual registers to hard registers.\n\n-fdump-rtl-web\nDump after live range splitting.\n\n-fdump-rtl-regclass\n-fdump-rtl-subregsofmodeinit\n-fdump-rtl-subregsofmodefinish\n-fdump-rtl-dfinit\n-fdump-rtl-dfinish\nThese dumps are defined but always produce empty files.\n\n-da\n-fdump-rtl-all\nProduce all the dumps listed above.\n\n-dA Annotate the assembler output with miscellaneous debugging information.\n\n-dD Dump all macro definitions, at the  end  of  preprocessing,  in  addition  to  normal\noutput.\n\n-dH Produce a core dump whenever an error occurs.\n\n-dp Annotate the assembler output with a comment indicating which pattern and alternative\nis used.  The length and cost of each instruction are also printed.\n\n-dP Dump  the  RTL  in  the  assembler output as a comment before each instruction.  Also\nturns on -dp annotation.\n\n-dx Just generate RTL for  a  function  instead  of  compiling  it.   Usually  used  with\n-fdump-rtl-expand.\n"
                },
                {
                    "name": "-fdump-debug",
                    "content": "Dump debugging information generated during the debug generation phase.\n"
                },
                {
                    "name": "-fdump-earlydebug",
                    "content": "Dump debugging information generated during the early debug generation phase.\n"
                },
                {
                    "name": "-fdump-noaddr",
                    "content": "When  doing debugging dumps, suppress address output.  This makes it more feasible to use\ndiff on debugging dumps for compiler invocations with different compiler binaries  and/or\ndifferent text / bss / data / heap / stack / dso start locations.\n"
                },
                {
                    "name": "-freport-bug",
                    "content": "Collect  and  dump  debug information into a temporary file if an internal compiler error\n(ICE) occurs.\n"
                },
                {
                    "name": "-fdump-unnumbered",
                    "content": "When doing debugging dumps, suppress instruction numbers and address output.  This  makes\nit  more  feasible to use diff on debugging dumps for compiler invocations with different\noptions, in particular with and without -g.\n"
                },
                {
                    "name": "-fdump-unnumbered-links",
                    "content": "When doing debugging dumps (see -d option above), suppress instruction  numbers  for  the\nlinks to the previous and next instructions in a sequence.\n"
                },
                {
                    "name": "-fdump-ipa-_",
                    "content": ""
                },
                {
                    "name": "-fdump-ipa-_ -_",
                    "content": "Control  the  dumping  at  various stages of inter-procedural analysis language tree to a\nfile.  The file name is generated by appending a switch specific  suffix  to  the  source\nfile  name,  and  the  file  is  created  in  the same directory as the output file.  The\nfollowing dumps are possible:\n\nall Enables all inter-procedural analysis dumps.\n\ncgraph\nDumps  information  about  call-graph  optimization,  unused  function  removal,  and\ninlining decisions.\n\ninline\nDump after function inlining.\n\nAdditionally,  the options -optimized, -missed, -note, and -all can be provided, with the\nsame meaning as for -fopt-info, defaulting to -optimized.\n\nFor example, -fdump-ipa-inline-optimized-missed will emit information on  callsites  that\nwere inlined, along with callsites that were not inlined.\n\nBy  default, the dump will contain messages about successful optimizations (equivalent to\n-optimized) together with low-level details about the analysis.\n"
                },
                {
                    "name": "-fdump-lang",
                    "content": "Dump language-specific information.  The file name is made  by  appending  .lang  to  the\nsource file name.\n"
                },
                {
                    "name": "-fdump-lang-all",
                    "content": ""
                },
                {
                    "name": "-fdump-lang-_",
                    "content": ""
                },
                {
                    "name": "-fdump-lang-_ -_",
                    "content": ""
                },
                {
                    "name": "-fdump-lang-_ -_",
                    "content": "Control  the dumping of language-specific information.  The options and filename portions\nbehave as described in the -fdump-tree option.  The following switch values are accepted:\n\nall Enable all language-specific dumps.\n\nclass\nDump class hierarchy information.  Virtual table information is emitted unless 'slim'\nis specified.  This option is applicable to C++ only.\n\nmodule\nDump module information.  Options lineno (locations),  graph  (reachability),  blocks\n(clusters),  uid  (serialization), alias (mergeable), asmname (Elrond), eh (mapper) &"
                },
                {
                    "name": "vops (macros)",
                    "content": "only.\n\nraw Dump the raw internal tree data.  This option is applicable to C++ only.\n"
                },
                {
                    "name": "-fdump-passes",
                    "content": "Print on stderr the list of optimization passes that are turned on and off by the current\ncommand-line options.\n"
                },
                {
                    "name": "-fdump-statistics-_",
                    "content": "Enable  and  control  dumping  of  pass  statistics in a separate file.  The file name is\ngenerated by appending a suffix ending in .statistics to the source file  name,  and  the\nfile  is  created in the same directory as the output file.  If the -option form is used,\n-stats causes counters to be summed over the whole compilation unit while -details  dumps\nevery  event  as the passes generate them.  The default with no option is to sum counters\nfor each function compiled.\n"
                },
                {
                    "name": "-fdump-tree-all",
                    "content": ""
                },
                {
                    "name": "-fdump-tree-_",
                    "content": ""
                },
                {
                    "name": "-fdump-tree-_ -_",
                    "content": ""
                },
                {
                    "name": "-fdump-tree-_ -_",
                    "content": "Control the dumping at various stages of processing the intermediate language tree  to  a\nfile.   If  the  -options  form  is  used, options is a list of - separated options which\ncontrol the details of the dump.  Not all options are applicable to all dumps; those that\nare not meaningful are ignored.  The following options are available\n\naddress\nPrint the address of each node.   Usually  this  is  not  meaningful  as  it  changes\naccording to the environment and source file.  Its primary use is for tying up a dump\nfile with a debug environment.\n\nasmname\nIf  \"DECLASSEMBLERNAME\" has been set for a given decl, use that in the dump instead\nof \"DECLNAME\".  Its primary use is ease of use working backward from  mangled  names\nin the assembly file.\n\nslim\nWhen  dumping front-end intermediate representations, inhibit dumping of members of a\nscope or body of a function merely because that scope has been  reached.   Only  dump\nsuch items when they are directly reachable by some other path.\n\nWhen dumping pretty-printed trees, this option inhibits dumping the bodies of control\nstructures.\n\nWhen dumping RTL, print the RTL in slim (condensed) form instead of the default LISP-\nlike representation.\n\nraw Print  a raw representation of the tree.  By default, trees are pretty-printed into a\nC-like representation.\n\ndetails\nEnable more  detailed  dumps  (not  honored  by  every  dump  option).  Also  include\ninformation from the optimization passes.\n\nstats\nEnable dumping various statistics about the pass (not honored by every dump option).\n\nblocks\nEnable showing basic block boundaries (disabled in raw dumps).\n\ngraph\nFor  each  of the other indicated dump files (-fdump-rtl-pass), dump a representation\nof the control flow graph suitable for viewing with GraphViz to file.passid.pass.dot.\nEach function in the file is pretty-printed as  a  subgraph,  so  that  GraphViz  can\nrender them all in a single plot.\n\nThis  option currently only works for RTL dumps, and the RTL is always dumped in slim\nform.\n\nvops\nEnable showing virtual operands for every statement.\n\nlineno\nEnable showing line numbers for statements.\n\nuid Enable showing the unique ID (\"DECLUID\") for each variable.\n\nverbose\nEnable showing the tree dump for each statement.\n\neh  Enable showing the EH region number holding each statement.\n\nscev\nEnable showing scalar evolution analysis details.\n\noptimized\nEnable showing optimization information (only available in certain passes).\n\nmissed\nEnable showing missed optimization information (only available in certain passes).\n\nnote\nEnable other detailed optimization information (only available in certain passes).\n\nall Turn on all options, except raw, slim, verbose and lineno.\n\noptall\nTurn on all optimization options, i.e., optimized, missed, and note.\n\nTo determine what tree dumps are available or find the dump for a pass of interest follow\nthe steps below.\n\n1.  Invoke GCC with -fdump-passes  and  in  the  stderr  output  look  for  a  code  that\ncorresponds  to  the pass you are interested in.  For example, the codes \"tree-evrp\",\n\"tree-vrp1\", and \"tree-vrp2\" correspond to the three Value Range Propagation  passes.\nThe number at the end distinguishes distinct invocations of the same pass.\n\n2.  To  enable  the creation of the dump file, append the pass code to the -fdump- option\nprefix and invoke GCC with it.  For example, to enable the dump from the Early  Value\nRange Propagation pass, invoke GCC with the -fdump-tree-evrp option.  Optionally, you\nmay  specify  the  name  of  the dump file.  If you don't specify one, GCC creates as\ndescribed below.\n\n3.  Find the pass dump in a file whose name is composed of three components separated  by\na  period:  the  name of the source file GCC was invoked to compile, a numeric suffix\nindicating the pass number followed by the letter t for tree passes (and the letter r\nfor RTL passes), and finally the pass code.  For example, the  Early  VRP  pass  dump\nmight  be  in a file named myfile.c.038t.evrp in the current working directory.  Note\nthat the numeric codes are not stable and may change  from  one  version  of  GCC  to\nanother.\n"
                },
                {
                    "name": "-fopt-info",
                    "content": ""
                },
                {
                    "name": "-fopt-info-_",
                    "content": ""
                },
                {
                    "name": "-fopt-info-_",
                    "content": "Controls  optimization  dumps  from  various optimization passes. If the -options form is\nused, options is a list of - separated option keywords to select  the  dump  details  and\noptimizations.\n\nThe options can be divided into three groups:\n\n1.  options describing what kinds of messages should be emitted,\n\n2.  options describing the verbosity of the dump, and\n\n3.  options describing which optimizations should be included.\n\nThe  options from each group can be freely mixed as they are non-overlapping. However, in\ncase of any conflicts, the later options override the  earlier  options  on  the  command\nline.\n\nThe following options control which kinds of messages should be emitted:\n\noptimized\nPrint information when an optimization is successfully applied. It is up to a pass to\ndecide  which  information  is relevant. For example, the vectorizer passes print the\nsource location of loops which are successfully vectorized.\n\nmissed\nPrint  information  about  missed  optimizations.  Individual  passes  control  which\ninformation to include in the output.\n\nnote\nPrint  verbose information about optimizations, such as certain transformations, more\ndetailed messages about decisions etc.\n\nall Print detailed optimization information. This includes optimized, missed, and note.\n\nThe following option controls the dump verbosity:\n\ninternals\nBy default, only \"high-level\" messages are emitted. This option  enables  additional,\nmore detailed, messages, which are likely to only be of interest to GCC developers.\n\nOne  or  more  of  the  following  option  keywords  can  be  used to describe a group of\noptimizations:\n\nipa Enable dumps from all interprocedural optimizations.\n\nloop\nEnable dumps from all loop optimizations.\n\ninline\nEnable dumps from all inlining optimizations.\n\nomp Enable dumps from all OMP (Offloading and Multi Processing) optimizations.\n\nvec Enable dumps from all vectorization optimizations.\n\noptall\nEnable dumps from all optimizations. This is a superset of  the  optimization  groups\nlisted above.\n\nIf  options  is  omitted,  it  defaults to optimized-optall, which means to dump messages\nabout successful optimizations from all the passes, omitting messages that are treated as\n\"internals\".\n\nIf the filename is provided, then the dumps from all  the  applicable  optimizations  are\nconcatenated  into  the  filename.   Otherwise  the  dump  is  output onto stderr. Though\nmultiple -fopt-info options are accepted, only one of them can  include  a  filename.  If\nother filenames are provided then all but the first such option are ignored.\n\nNote  that the output filename is overwritten in case of multiple translation units. If a\ncombined output from multiple  translation  units  is  desired,  stderr  should  be  used\ninstead.\n\nIn the following example, the optimization info is output to stderr:\n\ngcc -O3 -fopt-info\n\nThis example:\n\ngcc -O3 -fopt-info-missed=missed.all\n\noutputs missed optimization report from all the passes into missed.all, and this one:\n\ngcc -O2 -ftree-vectorize -fopt-info-vec-missed\n\nprints  information  about missed optimization opportunities from vectorization passes on\nstderr.  Note that -fopt-info-vec-missed is  equivalent  to  -fopt-info-missed-vec.   The\norder  of the optimization group names and message types listed after -fopt-info does not\nmatter.\n\nAs another example,\n\ngcc -O3 -fopt-info-inline-optimized-missed=inline.txt\n\noutputs information about missed optimizations as well as optimized  locations  from  all\nthe inlining passes into inline.txt.\n\nFinally, consider:\n\ngcc -fopt-info-vec-missed=vec.miss -fopt-info-loop-optimized=loop.opt\n\nHere the two output filenames vec.miss and loop.opt are in conflict since only one output\nfile  is  allowed.  In  this  case, only the first option takes effect and the subsequent\noptions are ignored. Thus only  vec.miss  is  produced  which  contains  dumps  from  the\nvectorizer about missed opportunities.\n"
                },
                {
                    "name": "-fsave-optimization-record",
                    "content": "Write  a SRCFILE.opt-record.json.gz file detailing what optimizations were performed, for\nthose optimizations that support -fopt-info.\n\nThis option is experimental and the format of the data within the compressed JSON file is\nsubject to change.\n\nIt is roughly equivalent to a machine-readable version of -fopt-info-all, as a collection\nof messages with  source  file,  line  number  and  column  number,  with  the  following\nadditional data for each message:\n\n*   the  execution  count  of the code being optimized, along with metadata about whether\nthis was from actual profile  data,  or  just  an  estimate,  allowing  consumers  to\nprioritize messages by code hotness,\n\n*   the function name of the code being optimized, where applicable,\n\n*   the \"inlining chain\" for the code being optimized, so that when a function is inlined\ninto  several  different  places  (which might themselves be inlined), the reader can\ndistinguish between the copies,\n\n*   objects identifying those parts of the message that refer to expressions,  statements\nor symbol-table nodes, which of these categories they are, and, when available, their\nsource code location,\n\n*   the GCC pass that emitted the message, and\n\n*   the location in GCC's own code from which the message was emitted\n\nAdditionally,  some  messages  are  logically  nested  within  other messages, reflecting\nimplementation details of the optimization passes.\n"
                },
                {
                    "name": "-fsched-verbose=_",
                    "content": "On targets that use instruction scheduling, this option controls the amount of  debugging\noutput the scheduler prints to the dump files.\n\nFor   n   greater   than   zero,   -fsched-verbose   outputs   the  same  information  as\n-fdump-rtl-sched1 and -fdump-rtl-sched2.  For n greater than one, it  also  output  basic\nblock  probabilities,  detailed ready list information and unit/insn info.  For n greater\nthan two, it includes RTL at abort point, control-flow and regions info.  And for n  over\nfour, -fsched-verbose also includes dependence info.\n"
                },
                {
                    "name": "-fenable-_ -_",
                    "content": ""
                },
                {
                    "name": "-fdisable-_ -_",
                    "content": "This  is a set of options that are used to explicitly disable/enable optimization passes.\nThese options are intended for use for debugging GCC.  Compiler users should use  regular\noptions for enabling/disabling passes instead.\n\n-fdisable-ipa-pass\nDisable IPA pass pass. pass is the pass name.  If the same pass is statically invoked\nin  the  compiler  multiple times, the pass name should be appended with a sequential\nnumber starting from 1.\n\n-fdisable-rtl-pass\n-fdisable-rtl-pass=range-list\nDisable RTL pass pass.  pass is the pass  name.   If  the  same  pass  is  statically\ninvoked  in  the  compiler  multiple  times,  the pass name should be appended with a\nsequential number starting from 1.  range-list is a comma-separated list of  function\nranges  or  assembler  names.  Each range is a number pair separated by a colon.  The\nrange is inclusive in both ends.  If the range is trivial, the  number  pair  can  be\nsimplified  as a single number.  If the function's call graph node's uid falls within\none of the specified ranges, the pass is disabled for  that  function.   The  uid  is\nshown  in  the  function  header  of a dump file, and the pass names can be dumped by\nusing option -fdump-passes.\n\n-fdisable-tree-pass\n-fdisable-tree-pass=range-list\nDisable tree pass pass.  See -fdisable-rtl for the description of option arguments.\n\n-fenable-ipa-pass\nEnable IPA pass pass.  pass is the pass name.  If the same pass is statically invoked\nin the compiler multiple times, the pass name should be appended  with  a  sequential\nnumber starting from 1.\n\n-fenable-rtl-pass\n-fenable-rtl-pass=range-list\nEnable  RTL  pass  pass.   See  -fdisable-rtl  for  option  argument  description and\nexamples.\n\n-fenable-tree-pass\n-fenable-tree-pass=range-list\nEnable tree pass pass.  See -fdisable-rtl for the description of option arguments.\n\nHere are some examples showing uses of these options.\n\n# disable ccp1 for all functions\n-fdisable-tree-ccp1\n# disable complete unroll for function whose cgraph node uid is 1\n-fenable-tree-cunroll=1\n# disable gcse2 for functions at the following ranges [1,1],\n# [300,400], and [400,1000]\n# disable gcse2 for functions foo and foo2\n-fdisable-rtl-gcse2=foo,foo2\n# disable early inlining\n-fdisable-tree-einline\n# disable ipa inlining\n-fdisable-ipa-inline\n# enable tree full unroll\n-fenable-tree-unroll\n"
                },
                {
                    "name": "-fchecking",
                    "content": ""
                },
                {
                    "name": "-fchecking=_",
                    "content": "Enable internal consistency checking.  The default depends on the compiler configuration.\n-fchecking=2 enables  further  internal  consistency  checking  that  might  affect  code\ngeneration.\n"
                },
                {
                    "name": "-frandom-seed=_",
                    "content": "This  option  provides  a  seed  that  GCC  uses in place of random numbers in generating\ncertain symbol names that have to be different in every compiled file.  It is  also  used\nto  place  unique  stamps  in coverage data files and the object files that produce them.\nYou can use the -frandom-seed option to produce reproducibly identical object files.\n\nThe string can either be a number (decimal, octal or hex)  or  an  arbitrary  string  (in\nwhich case it's converted to a number by computing CRC32).\n\nThe string should be different for every file you compile.\n"
                },
                {
                    "name": "-save-temps",
                    "content": "Store the usual \"temporary\" intermediate files permanently; name them as auxiliary output\nfiles, as specified described under -dumpbase and -dumpdir.\n\nWhen  used in combination with the -x command-line option, -save-temps is sensible enough\nto avoid overwriting an input source file with the  same  extension  as  an  intermediate\nfile.   The  corresponding  intermediate file may be obtained by renaming the source file\nbefore using -save-temps.\n"
                },
                {
                    "name": "-save-temps=cwd",
                    "content": "Equivalent to -save-temps -dumpdir ./.\n"
                },
                {
                    "name": "-save-temps=obj",
                    "content": "Equivalent to -save-temps -dumpdir outdir/, where outdir/ is the directory of the  output\nfile specified after the -o option, including any directory separators.  If the -o option\nis not used, the -save-temps=obj switch behaves like -save-temps=cwd.\n"
                },
                {
                    "name": "-time",
                    "content": "Report  the  CPU time taken by each subprocess in the compilation sequence.  For C source\nfiles, this is the compiler proper and assembler (plus the linker if linking is done).\n\nWithout the specification of an output file, the output looks like this:\n\n# cc1 0.12 0.01\n# as 0.00 0.01\n\nThe first number on each line is the \"user  time\",  that  is  time  spent  executing  the\nprogram  itself.   The  second  number  is  \"system time\", time spent executing operating\nsystem routines on behalf of the program.  Both numbers are in seconds.\n\nWith the specification of an output file, the output is appended to the named  file,  and\nit looks like this:\n\n0.12 0.01 cc1 <options>\n0.00 0.01 as <options>\n\nThe  \"user time\" and the \"system time\" are moved before the program name, and the options\npassed to the program are displayed, so that one can  later  tell  what  file  was  being\ncompiled, and with which options.\n"
                },
                {
                    "name": "-fdump-final-insns",
                    "content": "Dump  the  final  internal  representation  (RTL)  to  file.  If the optional argument is\nomitted (or if file is \".\"), the name of the dump file is determined by appending  \".gkd\"\nto the dump base name, see -dumpbase.\n"
                },
                {
                    "name": "-fcompare-debug",
                    "content": "If  no  error  occurs during compilation, run the compiler a second time, adding opts and\n-fcompare-debug-second to the arguments passed to the second compilation.  Dump the final\ninternal representation in both compilations, and print an error if they differ.\n\nIf the equal sign is omitted, the default -gtoggle is used.\n\nThe environment variable GCCCOMPAREDEBUG, if defined, non-empty and nonzero, implicitly\nenables -fcompare-debug.  If GCCCOMPAREDEBUG is defined to a  string  starting  with  a\ndash, then it is used for opts, otherwise the default -gtoggle is used.\n\n-fcompare-debug=,   with   the   equal   sign   but   without   opts,  is  equivalent  to\n-fno-compare-debug, which disables the dumping of the final representation and the second\ncompilation, preventing even GCCCOMPAREDEBUG from taking effect.\n\nTo verify full coverage during -fcompare-debug  testing,  set  GCCCOMPAREDEBUG  to  say\n-fcompare-debug-not-overridden,  which  GCC  rejects  as  an invalid option in any actual\ncompilation (rather than preprocessing, assembly or linking).  To  get  just  a  warning,\nsetting GCCCOMPAREDEBUG to -w%n-fcompare-debug not overridden will do.\n"
                },
                {
                    "name": "-fcompare-debug-second",
                    "content": "This  option is implicitly passed to the compiler for the second compilation requested by\n-fcompare-debug, along with options to silence warnings, and omitting other options  that\nwould  cause  the  compiler  to  produce  output to files or to standard output as a side\neffect.  Dump files and preserved temporary files are renamed so as to contain the  \".gk\"\nadditional  extension during the second compilation, to avoid overwriting those generated\nby the first.\n\nWhen this option is passed to the compiler driver, it causes the first compilation to  be\nskipped, which makes it useful for little other than debugging the compiler proper.\n"
                },
                {
                    "name": "-gtoggle",
                    "content": "Turn off generation of debug info, if leaving out this option generates it, or turn it on\nat level 2 otherwise.  The position of this argument in the command line does not matter;\nit  takes  effect  after  all  other  options are processed, and it does so only once, no\nmatter  how  many  times  it  is  given.   This  is  mainly  intended  to  be  used  with\n-fcompare-debug.\n"
                },
                {
                    "name": "-fvar-tracking-assignments-toggle",
                    "content": "Toggle -fvar-tracking-assignments, in the same way that -gtoggle toggles -g.\n"
                },
                {
                    "name": "-Q",
                    "content": "statistics about each pass when it finishes.\n",
                    "flag": "-Q"
                },
                {
                    "name": "-ftime-report",
                    "content": "Makes the compiler print some statistics about the time consumed by  each  pass  when  it\nfinishes.\n"
                },
                {
                    "name": "-ftime-report-details",
                    "content": "Record the time consumed by infrastructure parts separately for each pass.\n"
                },
                {
                    "name": "-fira-verbose=_",
                    "content": "Control  the  verbosity  of  the  dump  file  for the integrated register allocator.  The\ndefault value is 5.  If the value n is greater or equal to 10, the dump output is sent to\nstderr using the same format as n minus 10.\n"
                },
                {
                    "name": "-flto-report",
                    "content": "Prints a report with internal details on the workings of the  link-time  optimizer.   The\ncontents  of  this  report vary from version to version.  It is meant to be useful to GCC\ndevelopers when processing object files in LTO mode (via -flto).\n\nDisabled by default.\n"
                },
                {
                    "name": "-flto-report-wpa",
                    "content": "Like -flto-report, but only print for the WPA phase of link-time optimization.\n"
                },
                {
                    "name": "-fmem-report",
                    "content": "Makes the compiler print some  statistics  about  permanent  memory  allocation  when  it\nfinishes.\n"
                },
                {
                    "name": "-fmem-report-wpa",
                    "content": "Makes  the  compiler  print some statistics about permanent memory allocation for the WPA\nphase only.\n"
                },
                {
                    "name": "-fpre-ipa-mem-report",
                    "content": ""
                },
                {
                    "name": "-fpost-ipa-mem-report",
                    "content": "Makes the compiler print some statistics about  permanent  memory  allocation  before  or\nafter interprocedural optimization.\n"
                },
                {
                    "name": "-fmultiflags",
                    "content": "This  option  enables  multilib-aware  \"TFLAGS\" to be used to build target libraries with\noptions different from those the compiler is configured to use by  default,  through  the\nuse of specs\n\nLike  \"TFLAGS\",  this  allows  the  target  libraries  to  be built for portable baseline\nenvironments, while the compiler defaults to more demanding ones.  That's useful  because\nusers  can  easily override the defaults the compiler is configured to use to build their\nown programs, if the defaults  are  not  ideal  for  their  target  environment,  whereas\nrebuilding the runtime libraries is usually not as easy or desirable.\n\nUnlike  \"TFLAGS\",  the  use of specs enables different flags to be selected for different\nmultilibs.  The way to accomplish that is to build with make  TFLAGS=-fmultiflags,  after\nconfiguring --with-specs=%{fmultiflags:...}.\n\nThis option is discarded by the driver once it's done processing driver self spec.\n\nIt is also useful to check that \"TFLAGS\" are being used to build all target libraries, by\nconfiguring  a non-bootstrap compiler --with-specs='%{!fmultiflags:%emissing TFLAGS}' and\nbuilding the compiler and target libraries.\n"
                },
                {
                    "name": "-fprofile-report",
                    "content": "Makes the compiler print some statistics about consistency of the (estimated) profile and\neffect of individual passes.\n"
                },
                {
                    "name": "-fstack-usage",
                    "content": "Makes the compiler output stack usage information for  the  program,  on  a  per-function\nbasis.   The  filename  for the dump is made by appending .su to the auxname.  auxname is\ngenerated from the name of the output file, if explicitly specified  and  it  is  not  an\nexecutable,  otherwise  it  is  the  basename of the source file.  An entry is made up of\nthree fields:\n\n*   The name of the function.\n\n*   A number of bytes.\n\n*   One or more qualifiers: \"static\", \"dynamic\", \"bounded\".\n\nThe qualifier \"static\" means that the function manipulates the stack statically: a  fixed\nnumber  of  bytes  are allocated for the frame on function entry and released on function\nexit; no stack adjustments are otherwise made in the function.  The second field is  this\nfixed number of bytes.\n\nThe  qualifier  \"dynamic\"  means  that the function manipulates the stack dynamically: in\naddition to the static allocation described above, stack adjustments are made in the body\nof the function, for example  to  push/pop  arguments  around  function  calls.   If  the\nqualifier  \"bounded\"  is  also  present,  the  amount  of these adjustments is bounded at\ncompile time and the second field is an upper bound of the total amount of stack used  by\nthe  function.   If  it is not present, the amount of these adjustments is not bounded at\ncompile time and the second field only represents the bounded part.\n"
                },
                {
                    "name": "-fstats",
                    "content": "Emit statistics about front-end processing at the end of the compilation.  This option is\nsupported only by the C++ front end, and the information is generally only useful to  the\nG++ development team.\n"
                },
                {
                    "name": "-fdbg-cnt-list",
                    "content": "Print the name and the counter upper bound for all debug counters.\n"
                },
                {
                    "name": "-fdbg-cnt=_",
                    "content": "Set  the  internal  debug  counter lower and upper bound.  counter-value-list is a comma-\nseparated list of name:lowerbound1-upperbound1  [:lowerbound2-upperbound2...]  tuples\nwhich  sets  the  name  of  the counter and list of closed intervals.  The lowerbound is\noptional   and   is   zero   initialized    if    not    set.     For    example,    with\n-fdbg-cnt=dce:2-4:10-11,tailcall:10,  dbgcnt(dce)  returns true only for second, third,\nfourth, tenth and eleventh invocation.  For dbgcnt(tailcall) true is returned for first\n10 invocations.\n"
                },
                {
                    "name": "-print-file-name=_",
                    "content": "Print the full absolute name of  the  library  file  library  that  would  be  used  when\nlinking---and  don't  do  anything  else.  With this option, GCC does not compile or link\nanything; it just prints the file name.\n"
                },
                {
                    "name": "-print-multi-directory",
                    "content": "Print the directory name corresponding to the multilib selected  by  any  other  switches\npresent in the command line.  This directory is supposed to exist in GCCEXECPREFIX.\n"
                },
                {
                    "name": "-print-multi-lib",
                    "content": "Print  the  mapping  from multilib directory names to compiler switches that enable them.\nThe directory name is separated from the switches by ;, and each switch starts with an  @\ninstead  of  the  -,  without spaces between multiple switches.  This is supposed to ease\nshell processing.\n"
                },
                {
                    "name": "-print-multi-os-directory",
                    "content": "Print the path  to  OS  libraries  for  the  selected  multilib,  relative  to  some  lib\nsubdirectory.   If  OS libraries are present in the lib subdirectory and no multilibs are\nused, this is  usually  just  .,  if  OS  libraries  are  present  in  libsuffix  sibling\ndirectories this prints e.g. ../lib64, ../lib or ../lib32, or if OS libraries are present\nin lib/subdir subdirectories it prints e.g. amd64, sparcv9 or ev6.\n"
                },
                {
                    "name": "-print-multiarch",
                    "content": "Print  the  path  to  OS  libraries  for  the  selected  multiarch,  relative to some lib\nsubdirectory.\n"
                },
                {
                    "name": "-print-prog-name=_",
                    "content": "Like -print-file-name, but searches for a program such as cpp.\n"
                },
                {
                    "name": "-print-libgcc-file-name",
                    "content": "Same as -print-file-name=libgcc.a.\n\nThis is useful when you use -nostdlib or -nodefaultlibs but you  do  want  to  link  with\nlibgcc.a.  You can do:\n\ngcc -nostdlib <files>... `gcc -print-libgcc-file-name`\n"
                },
                {
                    "name": "-print-search-dirs",
                    "content": "Print the name of the configured installation directory and a list of program and library\ndirectories gcc searches---and don't do anything else.\n\nThis  is useful when gcc prints the error message installation problem, cannot exec cpp0:\nNo such file or directory.  To resolve this you either need to put  cpp0  and  the  other\ncompiler  components  where  gcc  expects  to  find  them, or you can set the environment\nvariable GCCEXECPREFIX to the directory where you installed  them.   Don't  forget  the\ntrailing /.\n"
                },
                {
                    "name": "-print-sysroot",
                    "content": "Print  the  target sysroot directory that is used during compilation.  This is the target\nsysroot specified either at configure time or using the --sysroot option,  possibly  with\nan  extra suffix that depends on compilation options.  If no target sysroot is specified,\nthe option prints nothing.\n"
                },
                {
                    "name": "-print-sysroot-headers-suffix",
                    "content": "Print the suffix added to the target sysroot when searching for headers, or give an error\nif the compiler is not configured with such a suffix---and don't do anything else.\n"
                },
                {
                    "name": "-dumpmachine",
                    "content": "Print the compiler's target  machine  (for  example,  i686-pc-linux-gnu)---and  don't  do\nanything else.\n"
                },
                {
                    "name": "-dumpversion",
                    "content": "Print  the  compiler version (for example, 3.0, 6.3.0 or 7)---and don't do anything else.\nThis is the compiler version used in filesystem paths and specs.  Depending  on  how  the\ncompiler  has been configured it can be just a single number (major version), two numbers\nseparated by a dot (major and minor version) or three numbers separated by  dots  (major,\nminor and patchlevel version).\n"
                },
                {
                    "name": "-dumpfullversion",
                    "content": "Print  the full compiler version---and don't do anything else. The output is always three\nnumbers separated by dots, major, minor and patchlevel version.\n"
                },
                {
                    "name": "-dumpspecs",
                    "content": "Print the compiler's built-in specs---and don't do anything else.  (This is used when GCC\nitself is being built.)\n"
                },
                {
                    "name": "Machine-Dependent Options",
                    "content": "Each target machine supported by GCC can have its own options---for example, to allow you  to\ncompile  for  a  particular processor variant or ABI, or to control optimizations specific to\nthat machine.  By convention, the names of machine-specific options start with -m.\n\nSome configurations of the compiler also support additional target-specific options,  usually\nfor compatibility with other compilers on the same platform.\n\nAArch64 Options\n\nThese options are defined for AArch64 implementations:\n"
                },
                {
                    "name": "-mabi=_",
                    "content": "Generate  code  for the specified data model.  Permissible values are ilp32 for SysV-like\ndata model where int, long int and pointers are 32 bits,  and  lp64  for  SysV-like  data\nmodel where int is 32 bits, but long int and pointers are 64 bits.\n\nThe  default  depends on the specific target configuration.  Note that the LP64 and ILP32\nABIs are not link-compatible; you must compile your entire program with the same ABI, and\nlink with a compatible set of libraries.\n"
                },
                {
                    "name": "-mbig-endian",
                    "content": "Generate  big-endian  code.   This  is  the  default  when  GCC  is  configured  for   an\naarch64be-*-* target.\n"
                },
                {
                    "name": "-mgeneral-regs-only",
                    "content": "Generate  code  which  uses  only  the  general-purpose registers.  This will prevent the\ncompiler from using floating-point and Advanced SIMD registers but will  not  impose  any\nrestrictions on the assembler.\n"
                },
                {
                    "name": "-mlittle-endian",
                    "content": "Generate  little-endian  code.   This  is  the  default  when  GCC  is  configured for an\naarch64-*-* but not an aarch64be-*-* target.\n"
                },
                {
                    "name": "-mcmodel=tiny",
                    "content": "Generate code for the tiny code model.  The program and its  statically  defined  symbols\nmust be within 1MB of each other.  Programs can be statically or dynamically linked.\n"
                },
                {
                    "name": "-mcmodel=small",
                    "content": "Generate  code  for the small code model.  The program and its statically defined symbols\nmust be within 4GB of each other.  Programs can  be  statically  or  dynamically  linked.\nThis is the default code model.\n"
                },
                {
                    "name": "-mcmodel=large",
                    "content": "Generate  code  for  the large code model.  This makes no assumptions about addresses and\nsizes of sections.  Programs can be statically linked only.  The -mcmodel=large option is\nincompatible with -mabi=ilp32, -fpic and -fPIC.\n"
                },
                {
                    "name": "-mstrict-align",
                    "content": ""
                },
                {
                    "name": "-mno-strict-align",
                    "content": "Avoid or allow generating memory accesses that may not be aligned  on  a  natural  object\nboundary as described in the architecture specification.\n"
                },
                {
                    "name": "-momit-leaf-frame-pointer",
                    "content": ""
                },
                {
                    "name": "-mno-omit-leaf-frame-pointer",
                    "content": "Omit or keep the frame pointer in leaf functions.  The former behavior is the default.\n"
                },
                {
                    "name": "-mstack-protector-guard=_",
                    "content": ""
                },
                {
                    "name": "-mstack-protector-guard-reg=_",
                    "content": ""
                },
                {
                    "name": "-mstack-protector-guard-offset=_",
                    "content": "Generate stack protection code using canary at guard.  Supported locations are global for\na global canary or sysreg for a canary in an appropriate system register.\n\nWith    the    latter    choice    the    options   -mstack-protector-guard-reg=reg   and\n-mstack-protector-guard-offset=offset furthermore specify which system register to use as\nbase register for reading the canary, and from what offset from that base register. There\nis no default register or offset as this is entirely for use within the Linux kernel.\n"
                },
                {
                    "name": "-mtls-dialect=desc",
                    "content": "Use TLS descriptors as the thread-local storage mechanism for  dynamic  accesses  of  TLS\nvariables.  This is the default.\n"
                },
                {
                    "name": "-mtls-dialect=traditional",
                    "content": "Use  traditional  TLS  as  the thread-local storage mechanism for dynamic accesses of TLS\nvariables.\n"
                },
                {
                    "name": "-mtls-size=_",
                    "content": "Specify bit size of immediate TLS offsets.  Valid values are 12, 24, 32, 48.  This option\nrequires binutils 2.26 or newer.\n"
                },
                {
                    "name": "-mfix-cortex-a53-835769",
                    "content": ""
                },
                {
                    "name": "-mno-fix-cortex-a53-835769",
                    "content": "Enable or disable the workaround for the ARM  Cortex-A53  erratum  number  835769.   This\ninvolves  inserting  a  NOP  instruction  between  memory instructions and 64-bit integer\nmultiply-accumulate instructions.\n"
                },
                {
                    "name": "-mfix-cortex-a53-843419",
                    "content": ""
                },
                {
                    "name": "-mno-fix-cortex-a53-843419",
                    "content": "Enable or disable the workaround for the ARM  Cortex-A53  erratum  number  843419.   This\nerratum workaround is made at link time and this will only pass the corresponding flag to\nthe linker.\n"
                },
                {
                    "name": "-mlow-precision-recip-sqrt",
                    "content": ""
                },
                {
                    "name": "-mno-low-precision-recip-sqrt",
                    "content": "Enable  or  disable  the  reciprocal  square root approximation.  This option only has an\neffect if -ffast-math or -funsafe-math-optimizations is  used  as  well.   Enabling  this\nreduces precision of reciprocal square root results to about 16 bits for single precision\nand to 32 bits for double precision.\n"
                },
                {
                    "name": "-mlow-precision-sqrt",
                    "content": ""
                },
                {
                    "name": "-mno-low-precision-sqrt",
                    "content": "Enable  or  disable  the  square  root  approximation.  This option only has an effect if\n-ffast-math or -funsafe-math-optimizations  is  used  as  well.   Enabling  this  reduces\nprecision of square root results to about 16 bits for single precision and to 32 bits for\ndouble precision.  If enabled, it implies -mlow-precision-recip-sqrt.\n"
                },
                {
                    "name": "-mlow-precision-div",
                    "content": ""
                },
                {
                    "name": "-mno-low-precision-div",
                    "content": "Enable  or  disable  the  division  approximation.   This  option  only  has an effect if\n-ffast-math or -funsafe-math-optimizations  is  used  as  well.   Enabling  this  reduces\nprecision  of  division  results to about 16 bits for single precision and to 32 bits for\ndouble precision.\n"
                },
                {
                    "name": "-mtrack-speculation",
                    "content": ""
                },
                {
                    "name": "-mno-track-speculation",
                    "content": "Enable or disable generation of additional code to track  speculative  execution  through\nconditional branches.  The tracking state can then be used by the compiler when expanding\ncalls to \"builtinspeculationsafecopy\" to permit a more efficient code sequence to be\ngenerated.\n"
                },
                {
                    "name": "-moutline-atomics",
                    "content": ""
                },
                {
                    "name": "-mno-outline-atomics",
                    "content": "Enable  or  disable  calls  to out-of-line helpers to implement atomic operations.  These\nhelpers will, at runtime, determine if the LSE instructions from ARMv8.1-A can  be  used;\nif  not, they will use the load/store-exclusive instructions that are present in the base\nARMv8.0 ISA.\n\nThis option is only applicable when compiling for the base ARMv8.0 instruction  set.   If\nusing  a later revision, e.g. -march=armv8.1-a or -march=armv8-a+lse, the ARMv8.1-Atomics\ninstructions will be used directly.  The same applies when using -mcpu= when the selected\ncpu supports the lse feature.  This option is on by default.\n"
                },
                {
                    "name": "-march=_",
                    "content": "Specify the name of  the  target  architecture  and,  optionally,  one  or  more  feature\nmodifiers.  This option has the form -march=arch{+[no]feature}*.\n\nThe  table  below  summarizes  the permissible values for arch and the features that they\nenable by default:\n\narch value : Architecture : Includes by default\narmv8-a : Armv8-A : +fp, +simd\narmv8.1-a : Armv8.1-A : armv8-a, +crc, +lse, +rdma\narmv8.2-a : Armv8.2-A : armv8.1-a\narmv8.3-a : Armv8.3-A : armv8.2-a, +pauth\narmv8.4-a : Armv8.4-A : armv8.3-a, +flagm, +fp16fml, +dotprod\narmv8.5-a : Armv8.5-A : armv8.4-a, +sb, +ssbs, +predres\narmv8.6-a : Armv8.6-A : armv8.5-a, +bf16, +i8mm\narmv8.7-a : Armv8.7-A : armv8.6-a, +ls64\narmv8.8-a : Armv8.8-a : armv8.7-a, +mops\narmv9-a : Armv9-A : armv8.5-a, +sve, +sve2\narmv9.1-a : Armv9.1-A : armv9-a, +bf16, +i8mm\narmv9.2-a : Armv9.2-A : armv9.1-a, +ls64\narmv9.3-a : Armv9.3-A : armv9.2-a, +mops\narmv8-r : Armv8-R : armv8-r\n\nThe value native is available on native AArch64 GNU/Linux and causes the compiler to pick\nthe architecture of the host system.  This option has no effect if the compiler is unable\nto recognize the architecture of the host system,\n\nThe   permissible   values   for   feature   are   listed   in   the    sub-section    on\naarch64-feature-modifiers,,-march and -mcpu Feature Modifiers.  Where conflicting feature\nmodifiers are specified, the right-most feature is used.\n\nGCC uses name to determine what kind of instructions it can emit when generating assembly\ncode.  If -march is specified without either of -mtune or -mcpu also being specified, the\ncode is tuned to perform well across a range of target processors implementing the target\narchitecture.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "Specify the name of the target processor for which GCC should tune the performance of the\ncode.    Permissible  values  for  this  option  are:  generic,  cortex-a35,  cortex-a53,\ncortex-a55, cortex-a57, cortex-a72,  cortex-a73,  cortex-a75,  cortex-a76,  cortex-a76ae,\ncortex-a77,  cortex-a65, cortex-a65ae, cortex-a34, cortex-a78, cortex-a78ae, cortex-a78c,\nares, exynos-m1, emag, falkor, neoverse-512tvb,  neoverse-e1,  neoverse-n1,  neoverse-n2,\nneoverse-v1, neoverse-v2, qdf24xx, saphira, phecda, xgene1, vulcan, octeontx, octeontx81,\nocteontx83,    octeontx2,    octeontx2t98,   octeontx2t96   octeontx2t93,   octeontx2f95,\nocteontx2f95n, octeontx2f95mm, a64fx, thunderx, thunderxt88, thunderxt88p1,  thunderxt81,\ntsv110,    thunderxt83,   thunderx2t99,   thunderx3t110,   zeus,   cortex-a57.cortex-a53,\ncortex-a72.cortex-a53,           cortex-a73.cortex-a35,            cortex-a73.cortex-a53,\ncortex-a75.cortex-a55,    cortex-a76.cortex-a55,   cortex-r82,   cortex-x1,   cortex-x1c,\ncortex-x2,  cortex-x3,  cortex-a510,   cortex-a710,   cortex-a715,   ampere1,   ampere1a,\ncobalt-100 and native.\n\nThe    values    cortex-a57.cortex-a53,   cortex-a72.cortex-a53,   cortex-a73.cortex-a35,\ncortex-a73.cortex-a53,  cortex-a75.cortex-a55,  cortex-a76.cortex-a55  specify  that  GCC\nshould tune for a big.LITTLE system.\n\nThe  value  neoverse-512tvb  specifies  that  GCC should tune for Neoverse cores that (a)\nimplement SVE and (b) have a total vector bandwidth of 512  bits  per  cycle.   In  other\nwords,  the  option  tells  GCC  to  tune  for  Neoverse cores that can execute 4 128-bit\nAdvanced SIMD arithmetic instructions a cycle and that can execute an  equivalent  number\nof SVE arithmetic instructions per cycle (2 for 256-bit SVE, 4 for 128-bit SVE).  This is\nmore  general  than tuning for a specific core like Neoverse V1 but is more specific than\nthe default tuning described below.\n\nAdditionally on native AArch64 GNU/Linux systems the value native  tunes  performance  to\nthe  host  system.   This option has no effect if the compiler is unable to recognize the\nprocessor of the host system.\n\nWhere none of -mtune=, -mcpu= or -march= are specified, the code is tuned to perform well\nacross a range of target processors.\n\nThis option cannot be suffixed by feature modifiers.\n"
                },
                {
                    "name": "-mcpu=_",
                    "content": "Specify the name of the target processor, optionally suffixed  by  one  or  more  feature\nmodifiers.   This  option  has  the  form -mcpu=cpu{+[no]feature}*, where the permissible\nvalues for cpu are the same as those available for -mtune.  The  permissible  values  for\nfeature  are documented in the sub-section on aarch64-feature-modifiers,,-march and -mcpu\nFeature Modifiers.  Where conflicting feature modifiers  are  specified,  the  right-most\nfeature is used.\n\nGCC uses name to determine what kind of instructions it can emit when generating assembly\ncode  (as  if  by  -march)  and  to  determine the target processor for which to tune for\nperformance (as if by -mtune).  Where this option is used in conjunction with  -march  or\n-mtune, those options take precedence over the appropriate part of this option.\n\n-mcpu=neoverse-512tvb  is  special  in  that  it  does  not refer to a specific core, but\ninstead refers to all Neoverse cores that (a) implement SVE and (b) have a  total  vector\nbandwidth  of  512  bits  a  cycle.   Unless  overridden by -march, -mcpu=neoverse-512tvb\ngenerates code that can run on a Neoverse  V1  core,  since  Neoverse  V1  is  the  first\nNeoverse  core with these properties.  Unless overridden by -mtune, -mcpu=neoverse-512tvb\ntunes code in the same way as for -mtune=neoverse-512tvb.\n"
                },
                {
                    "name": "-moverride=_",
                    "content": "Override tuning decisions made by the back-end in response  to  a  -mtune=  switch.   The\nsyntax, semantics, and accepted values for string in this option are not guaranteed to be\nconsistent across releases.\n\nThis option is only intended to be useful when developing GCC.\n"
                },
                {
                    "name": "-mverbose-cost-dump",
                    "content": "Enable  verbose  cost model dumping in the debug dump files.  This option is provided for\nuse in debugging the compiler.\n"
                },
                {
                    "name": "-mpc-relative-literal-loads",
                    "content": ""
                },
                {
                    "name": "-mno-pc-relative-literal-loads",
                    "content": "Enable or disable PC-relative literal loads.  With this option literal pools are accessed\nusing a single instruction and emitted after each function.  This limits the maximum size\nof functions to 1MB.  This is enabled by default for -mcmodel=tiny.\n"
                },
                {
                    "name": "-msign-return-address=_",
                    "content": "Select the function scope on which return address signing will be  applied.   Permissible\nvalues  are  none, which disables return address signing, non-leaf, which enables pointer\nsigning for functions which are not  leaf  functions,  and  all,  which  enables  pointer\nsigning for all functions.  The default value is none. This option has been deprecated by\n-mbranch-protection.\n"
                },
                {
                    "name": "-mbranch-protection=_",
                    "content": "Select  the  branch  protection  features  to use.  none is the default and turns off all\ntypes of branch protection.  standard turns on all types of branch  protection  features.\nIf  a feature has additional tuning options, then standard sets it to its standard level.\npac-ret[+leaf] turns on return address signing to its standard level:  signing  functions\nthat  save  the  return  address to memory (non-leaf functions will practically always do\nthis) using the a-key.  The optional argument leaf can be used to extend the  signing  to\ninclude  leaf  functions.   The optional argument b-key can be used to sign the functions\nwith the B-key  instead  of  the  A-key.   bti  turns  on  branch  target  identification\nmechanism.\n"
                },
                {
                    "name": "-mharden-sls=_",
                    "content": "Enable  compiler  hardening  against  straight  line speculation (SLS).  opts is a comma-\nseparated list of the following options:\n\nretbr\nblr\n\nIn addition, -mharden-sls=all enables all SLS hardening while -mharden-sls=none  disables\nall SLS hardening.\n"
                },
                {
                    "name": "-msve-vector-bits=_",
                    "content": "Specify  the  number  of  bits in an SVE vector register.  This option only has an effect\nwhen SVE is enabled.\n\nGCC supports two forms of SVE code generation: \"vector-length agnostic\" output that works\nwith any size of vector register and \"vector-length specific\" output that allows  GCC  to\nmake assumptions about the vector length when it is useful for optimization reasons.  The\npossible values of bits are: scalable, 128, 256, 512, 1024 and 2048.  Specifying scalable\nselects  vector-length  agnostic output.  At present -msve-vector-bits=128 also generates\nvector-length agnostic output for big-endian targets.  All other values generate  vector-\nlength  specific code.  The behavior of these values may change in future releases and no\nvalue except scalable should be relied on for producing  code  that  is  portable  across\ndifferent hardware SVE vector lengths.\n\nThe default is -msve-vector-bits=scalable, which produces vector-length agnostic code.\n"
                },
                {
                    "name": "-march  -mcpu",
                    "content": "Feature  modifiers  used with -march and -mcpu can be any of the following and their inverses\nnofeature:\n\ncrc Enable CRC extension.  This is on by default for -march=armv8.1-a.\n"
                },
                {
                    "name": "crypto",
                    "content": "Enable  Crypto  extension.   This  also  enables   Advanced   SIMD   and   floating-point\ninstructions.\n\nfp  Enable  floating-point  instructions.   This is on by default for all possible values for\noptions -march and -mcpu.\n"
                },
                {
                    "name": "simd",
                    "content": "Enable Advanced SIMD instructions.  This also enables floating-point instructions.   This\nis on by default for all possible values for options -march and -mcpu.\n\nsve Enable  Scalable  Vector  Extension  instructions.   This  also enables Advanced SIMD and\nfloating-point instructions.\n\nlse Enable Large System Extension instructions.  This is on by default for -march=armv8.1-a.\n"
                },
                {
                    "name": "rdma",
                    "content": "Enable Round Double  Multiply  Accumulate  instructions.   This  is  on  by  default  for\n-march=armv8.1-a.\n"
                },
                {
                    "name": "fp16",
                    "content": "Enable FP16 extension.  This also enables floating-point instructions.\n"
                },
                {
                    "name": "fp16fml",
                    "content": "Enable  FP16  fmla  extension.   This  also  enables  FP16  extensions and floating-point\ninstructions. This option is enabled by default for -march=armv8.4-a. Use of this  option\nwith architectures prior to Armv8.2-A is not supported.\n"
                },
                {
                    "name": "rcpc",
                    "content": "Enable  the  RCpc  extension.   This  enables the use of the LDAPR instructions for load-\nacquire atomic semantics, and  passes  it  on  to  the  assembler,  enabling  inline  asm\nstatements to use instructions from the RCpc extension.\n"
                },
                {
                    "name": "dotprod",
                    "content": "Enable the Dot Product extension.  This also enables Advanced SIMD instructions.\n\naes Enable  the  Armv8-a  aes  and  pmull  crypto extension.  This also enables Advanced SIMD\ninstructions.\n"
                },
                {
                    "name": "sha2",
                    "content": "Enable the Armv8-a sha2 crypto extension.  This also enables Advanced SIMD instructions.\n"
                },
                {
                    "name": "sha3",
                    "content": "Enable  the  sha512  and  sha3  crypto  extension.   This  also  enables  Advanced   SIMD\ninstructions. Use of this option with architectures prior to Armv8.2-A is not supported.\n\nsm4 Enable  the  sm3 and sm4 crypto extension.  This also enables Advanced SIMD instructions.\nUse of this option with architectures prior to Armv8.2-A is not supported.\n"
                },
                {
                    "name": "profile",
                    "content": "Enable the Statistical Profiling extension.  This option is only to enable the  extension\nat the assembler level and does not affect code generation.\n\nrng Enable  the  Armv8.5-a  Random  Number  instructions.   This option is only to enable the\nextension at the assembler level and does not affect code generation.\n"
                },
                {
                    "name": "memtag",
                    "content": "Enable the Armv8.5-a Memory Tagging Extensions.  Use of this  option  with  architectures\nprior to Armv8.5-A is not supported.\n\nsb  Enable  the  Armv8-a  Speculation Barrier instruction.  This option is only to enable the\nextension at the assembler level and does not affect code  generation.   This  option  is\nenabled by default for -march=armv8.5-a.\n"
                },
                {
                    "name": "ssbs",
                    "content": "Enable  the  Armv8-a  Speculative  Store Bypass Safe instruction.  This option is only to\nenable the extension at the assembler level and does not affect  code  generation.   This\noption is enabled by default for -march=armv8.5-a.\n"
                },
                {
                    "name": "predres",
                    "content": "Enable  the  Armv8-a Execution and Data Prediction Restriction instructions.  This option\nis only to enable the  extension  at  the  assembler  level  and  does  not  affect  code\ngeneration.  This option is enabled by default for -march=armv8.5-a.\n"
                },
                {
                    "name": "sve2",
                    "content": "Enable the Armv8-a Scalable Vector Extension 2.  This also enables SVE instructions.\n"
                },
                {
                    "name": "sve2-bitperm",
                    "content": "Enable SVE2 bitperm instructions.  This also enables SVE2 instructions.\n"
                },
                {
                    "name": "sve2-sm4",
                    "content": "Enable SVE2 sm4 instructions.  This also enables SVE2 instructions.\n"
                },
                {
                    "name": "sve2-aes",
                    "content": "Enable SVE2 aes instructions.  This also enables SVE2 instructions.\n"
                },
                {
                    "name": "sve2-sha3",
                    "content": "Enable SVE2 sha3 instructions.  This also enables SVE2 instructions.\n\ntme Enable the Transactional Memory Extension.\n"
                },
                {
                    "name": "i8mm",
                    "content": "Enable  8-bit  Integer Matrix Multiply instructions.  This also enables Advanced SIMD and\nfloating-point instructions.  This option is enabled  by  default  for  -march=armv8.6-a.\nUse of this option with architectures prior to Armv8.2-A is not supported.\n"
                },
                {
                    "name": "f32mm",
                    "content": "Enable  32-bit  Floating  point  Matrix  Multiply  instructions.   This  also enables SVE\ninstructions.  Use of this option with architectures prior to Armv8.2-A is not supported.\n"
                },
                {
                    "name": "f64mm",
                    "content": "Enable 64-bit Floating  point  Matrix  Multiply  instructions.   This  also  enables  SVE\ninstructions.  Use of this option with architectures prior to Armv8.2-A is not supported.\n"
                },
                {
                    "name": "bf16",
                    "content": "Enable brain half-precision floating-point instructions.  This also enables Advanced SIMD\nand floating-point instructions.  This option is enabled by default for -march=armv8.6-a.\nUse of this option with architectures prior to Armv8.2-A is not supported.\n"
                },
                {
                    "name": "ls64",
                    "content": "Enable  the  64-byte atomic load and store instructions for accelerators.  This option is\nenabled by default for -march=armv8.7-a.\n"
                },
                {
                    "name": "mops",
                    "content": "Enable the  instructions  to  accelerate  memory  operations  like  \"memcpy\",  \"memmove\",\n\"memset\".  This option is enabled by default for -march=armv8.8-a\n"
                },
                {
                    "name": "flagm",
                    "content": "Enable the Flag Manipulation instructions Extension.\n"
                },
                {
                    "name": "pauth",
                    "content": "Enable the Pointer Authentication Extension.\n"
                },
                {
                    "name": "cssc",
                    "content": "Enable the Common Short Sequence Compression instructions.\n\nFeature  crypto  implies  aes,  sha2,  and  simd, which implies fp.  Conversely, nofp implies\nnosimd, which implies nocrypto, noaes and nosha2.\n\nAdapteva Epiphany Options\n\nThese -m options are defined for Adapteva Epiphany:\n"
                },
                {
                    "name": "-mhalf-reg-file",
                    "content": "Don't allocate any register in the range \"r32\"...\"r63\".   That  allows  code  to  run  on\nhardware variants that lack these registers.\n"
                },
                {
                    "name": "-mprefer-short-insn-regs",
                    "content": "Preferentially  allocate  registers  that  allow  short instruction generation.  This can\nresult in increased instruction count, so this may either reduce or increase overall code\nsize.\n"
                },
                {
                    "name": "-mbranch-cost=_",
                    "content": "Set the cost of branches to roughly num \"simple\"  instructions.   This  cost  is  only  a\nheuristic and is not guaranteed to produce consistent results across releases.\n"
                },
                {
                    "name": "-mcmove",
                    "content": "Enable the generation of conditional moves.\n"
                },
                {
                    "name": "-mnops=_",
                    "content": "Emit num NOPs before every other generated instruction.\n"
                },
                {
                    "name": "-mno-soft-cmpsf",
                    "content": "For  single-precision floating-point comparisons, emit an \"fsub\" instruction and test the\nflags.  This is faster than a software comparison, but can get incorrect results  in  the\npresence  of  NaNs,  or  when  two  different  small numbers are compared such that their\ndifference is calculated as zero.  The default is -msoft-cmpsf, which  uses  slower,  but\nIEEE-compliant, software comparisons.\n"
                },
                {
                    "name": "-mstack-offset=_",
                    "content": "Set  the  offset  between the top of the stack and the stack pointer.  E.g., a value of 8\nmeans that the eight bytes in the range \"sp+0...sp+7\"  can  be  used  by  leaf  functions\nwithout  stack  allocation.  Values other than 8 or 16 are untested and unlikely to work.\nNote also that this option changes the ABI; compiling a program with  a  different  stack\noffset  than  the libraries have been compiled with generally does not work.  This option\ncan be useful if you want to evaluate if a different stack offset would give  you  better\ncode,  but  to  actually  use  a  different stack offset to build working programs, it is\nrecommended to configure  the  toolchain  with  the  appropriate  --with-stack-offset=num\noption.\n"
                },
                {
                    "name": "-mno-round-nearest",
                    "content": "Make the scheduler assume that the rounding mode has been set to truncating.  The default\nis -mround-nearest.\n"
                },
                {
                    "name": "-mlong-calls",
                    "content": "If  not  otherwise specified by an attribute, assume all calls might be beyond the offset\nrange of the \"b\" / \"bl\" instructions, and therefore load  the  function  address  into  a\nregister before performing a (otherwise direct) call.  This is the default.\n"
                },
                {
                    "name": "-mshort-calls",
                    "content": "If  not  otherwise specified by an attribute, assume all direct calls are in the range of\nthe \"b\" / \"bl\" instructions, so use these instructions for direct calls.  The default  is\n-mlong-calls.\n"
                },
                {
                    "name": "-msmall16",
                    "content": "Assume  addresses  can  be  loaded  as  16-bit  unsigned  values.  This does not apply to\nfunction addresses for which -mlong-calls semantics are in effect.\n"
                },
                {
                    "name": "-mfp-mode=_",
                    "content": "Set the prevailing mode of the floating-point unit.  This determines  the  floating-point\nmode  that  is  provided and expected at function call and return time.  Making this mode\nmatch the mode you predominantly need at function start can make  your  programs  smaller\nand faster by avoiding unnecessary mode switches.\n\nmode can be set to one the following values:\n\ncaller\nAny  mode  at  function  entry  is  valid, and retained or restored when the function\nreturns, and when it calls other  functions.   This  mode  is  useful  for  compiling\nlibraries  or  other  compilation  units you might want to incorporate into different\nprograms with different prevailing FPU modes, and the convenience of  being  able  to\nuse  a  single  object  file outweighs the size and speed overhead for any extra mode\nswitching that might be needed, compared with  what  would  be  needed  with  a  more\nspecific choice of prevailing FPU mode.\n\ntruncate\nThis  is  the  mode  used for floating-point calculations with truncating (i.e. round\ntowards zero) rounding  mode.   That  includes  conversion  from  floating  point  to\ninteger.\n\nround-nearest\nThis  is  the mode used for floating-point calculations with round-to-nearest-or-even\nrounding mode.\n\nint This is the mode used to perform integer  calculations  in  the  FPU,  e.g.   integer\nmultiply, or integer multiply-and-accumulate.\n\nThe default is -mfp-mode=caller\n"
                },
                {
                    "name": "-mno-split-lohi",
                    "content": ""
                },
                {
                    "name": "-mno-postinc",
                    "content": ""
                },
                {
                    "name": "-mno-postmodify",
                    "content": "Code  generation tweaks that disable, respectively, splitting of 32-bit loads, generation\nof post-increment addresses, and generation of post-modify addresses.  The  defaults  are\nmsplit-lohi, -mpost-inc, and -mpost-modify.\n"
                },
                {
                    "name": "-mnovect-double",
                    "content": "Change  the  preferred  SIMD  mode  to  SImode.  The default is -mvect-double, which uses\nDImode as preferred SIMD mode.\n"
                },
                {
                    "name": "-max-vect-align=_",
                    "content": "The maximum alignment for SIMD vector mode types.  num may be 4 or 8.  The default is  8.\nNote  that  this  is  an  ABI  change,  even  though many library function interfaces are\nunaffected if they don't use  SIMD  vector  modes  in  places  that  affect  size  and/or\nalignment of relevant types.\n"
                },
                {
                    "name": "-msplit-vecmove-early",
                    "content": "Split  vector moves into single word moves before reload.  In theory this can give better\nregister allocation, but so far the reverse seems to be generally the case.\n"
                },
                {
                    "name": "-m1reg-_",
                    "content": "Specify a register to hold the constant -1, which makes loading small negative  constants\nand certain bitmasks faster.  Allowable values for reg are r43 and r63, which specify use\nof  that register as a fixed register, and none, which means that no register is used for\nthis purpose.  The default is -m1reg-none.\n\nAMD GCN Options\n\nThese options are defined specifically for the AMD GCN port.\n"
                },
                {
                    "name": "-march=_",
                    "content": ""
                },
                {
                    "name": "-mtune=_",
                    "content": "Set architecture type or tuning for gpu. Supported values for gpu are\n\nfiji\nCompile for GCN3 Fiji devices (gfx803).\n\ngfx900\nCompile for GCN5 Vega 10 devices (gfx900).\n\ngfx906\nCompile for GCN5 Vega 20 devices (gfx906).\n\ngfx908\nCompile for CDNA1 Instinct MI100 series devices (gfx908).\n\ngfx90a\nCompile for CDNA2 Instinct MI200 series devices (gfx90a).\n"
                },
                {
                    "name": "-msram-ecc=on",
                    "content": ""
                },
                {
                    "name": "-msram-ecc=off",
                    "content": ""
                },
                {
                    "name": "-msram-ecc=any",
                    "content": "Compile binaries suitable for devices with the SRAM-ECC  feature  enabled,  disabled,  or\neither mode.  This feature can be enabled per-process on some devices.  The compiled code\nmust match the device mode. The default is any, for devices that support it.\n"
                },
                {
                    "name": "-mstack-size=_",
                    "content": "Specify how many bytes of stack space will be requested for each GPU thread (wave-front).\nBeware  that  there  may  be  many threads and limited memory available.  The size of the\nstack allocation may also have an impact on run-time performance.  The  default  is  32KB\nwhen using OpenACC or OpenMP, and 1MB otherwise.\n"
                },
                {
                    "name": "-mxnack",
                    "content": "Compile  binaries  suitable  for  devices  with  the XNACK feature enabled.  Some devices\nalways require XNACK and some allow the user to configure XNACK.  The compiled code  must\nmatch  the  device  mode.   The  default  is  -mno-xnack.   At  present  this option is a\nplaceholder for support that is not yet implemented.\n\nARC Options\n\nThe following options control the architecture variant for which code is being compiled:\n"
                },
                {
                    "name": "-mbarrel-shifter",
                    "content": "Generate  instructions  supported  by  barrel  shifter.   This  is  the  default   unless\n-mcpu=ARC601 or -mcpu=ARCEM is in effect.\n"
                },
                {
                    "name": "-mjli-always",
                    "content": "Force  to  call  a function using jlis instruction.  This option is valid only for ARCv2\narchitecture.\n"
                },
                {
                    "name": "-mcpu=_",
                    "content": "Set architecture type, register usage, and instruction  scheduling  parameters  for  cpu.\nThere   are  also  shortcut  alias  options  available  for  backward  compatibility  and\nconvenience.  Supported values for cpu are\n\narc600\nCompile for ARC600.  Aliases: -mA6, -mARC600.\n\narc601\nCompile for ARC601.  Alias: -mARC601.\n\narc700\nCompile for ARC700.  Aliases: -mA7, -mARC700.  This is the  default  when  configured\nwith --with-cpu=arc700.\n\narcem\nCompile for ARC EM.\n\narchs\nCompile for ARC HS.\n\nem  Compile for ARC EM CPU with no hardware extensions.\n\nem4 Compile for ARC EM4 CPU.\n\nem4dmips\nCompile for ARC EM4 DMIPS CPU.\n\nem4fpus\nCompile for ARC EM4 DMIPS CPU with the single-precision floating-point extension.\n\nem4fpuda\nCompile  for ARC EM4 DMIPS CPU with single-precision floating-point and double assist\ninstructions.\n\nhs  Compile for ARC HS CPU with no hardware extensions except the atomic instructions.\n\nhs34\nCompile for ARC HS34 CPU.\n\nhs38\nCompile for ARC HS38 CPU.\n\nhs38linux\nCompile for ARC HS38 CPU with all hardware extensions on.\n\nhs4x\nCompile for ARC HS4x CPU.\n\nhs4xd\nCompile for ARC HS4xD CPU.\n\nhs4xrel31\nCompile for ARC HS4x CPU release 3.10a.\n\narc600norm\nCompile for ARC 600 CPU with \"norm\" instructions enabled.\n\narc600mul32x16\nCompile for ARC 600 CPU with \"norm\" and 32x16-bit multiply instructions enabled.\n\narc600mul64\nCompile for ARC 600 CPU with \"norm\" and \"mul64\"-family instructions enabled.\n\narc601norm\nCompile for ARC 601 CPU with \"norm\" instructions enabled.\n\narc601mul32x16\nCompile for ARC 601 CPU with \"norm\" and 32x16-bit multiply instructions enabled.\n\narc601mul64\nCompile for ARC 601 CPU with \"norm\" and \"mul64\"-family instructions enabled.\n\nnps400\nCompile for ARC 700 on NPS400 chip.\n\nemmini\nCompile for ARC EM minimalist configuration featuring reduced register set.\n"
                },
                {
                    "name": "-mdpfp",
                    "content": ""
                },
                {
                    "name": "-mdpfp-compact",
                    "content": "Generate double-precision FPX instructions, tuned for the compact implementation.\n"
                },
                {
                    "name": "-mdpfp-fast",
                    "content": "Generate double-precision FPX instructions, tuned for the fast implementation.\n"
                },
                {
                    "name": "-mno-dpfp-lrsr",
                    "content": "Disable \"lr\" and \"sr\" instructions from using FPX extension aux registers.\n"
                },
                {
                    "name": "-mea",
                    "content": "Generate extended arithmetic instructions.  Currently only \"divaw\", \"adds\",  \"subs\",  and\n\"sat16\" are supported.  Only valid for -mcpu=ARC700.\n"
                },
                {
                    "name": "-mno-mpy",
                    "content": "Do not generate \"mpy\"-family instructions for ARC700.  This option is deprecated.\n"
                },
                {
                    "name": "-mmul32x16",
                    "content": "Generate 32x16-bit multiply and multiply-accumulate instructions.\n"
                },
                {
                    "name": "-mmul64",
                    "content": "Generate \"mul64\" and \"mulu64\" instructions.  Only valid for -mcpu=ARC600.\n"
                },
                {
                    "name": "-mnorm",
                    "content": "Generate \"norm\" instructions.  This is the default if -mcpu=ARC700 is in effect.\n"
                },
                {
                    "name": "-mspfp",
                    "content": ""
                },
                {
                    "name": "-mspfp-compact",
                    "content": "Generate single-precision FPX instructions, tuned for the compact implementation.\n"
                },
                {
                    "name": "-mspfp-fast",
                    "content": "Generate single-precision FPX instructions, tuned for the fast implementation.\n"
                },
                {
                    "name": "-msimd",
                    "content": "Enable  generation of ARC SIMD instructions via target-specific builtins.  Only valid for\n-mcpu=ARC700.\n"
                },
                {
                    "name": "-msoft-float",
                    "content": "This option ignored; it is provided for compatibility purposes only.  Software  floating-\npoint code is emitted by default, and this default can overridden by FPX options; -mspfp,\n-mspfp-compact,  or  -mspfp-fast  for  single  precision,  and -mdpfp, -mdpfp-compact, or\n-mdpfp-fast for double precision.\n"
                },
                {
                    "name": "-mswap",
                    "content": "Generate \"swap\" instructions.\n"
                },
                {
                    "name": "-matomic",
                    "content": "This enables use of the locked  load/store  conditional  extension  to  implement  atomic\nmemory built-in functions.  Not available for ARC 6xx or ARC EM cores.\n"
                },
                {
                    "name": "-mdiv-rem",
                    "content": "Enable \"div\" and \"rem\" instructions for ARCv2 cores.\n"
                },
                {
                    "name": "-mcode-density",
                    "content": "Enable code density instructions for ARC EM.  This option is on by default for ARC HS.\n"
                },
                {
                    "name": "-mll64",
                    "content": "Enable double load/store operations for ARC HS cores.\n"
                },
                {
                    "name": "-mtp-regno=_",
                    "content": "Specify thread pointer register number.\n"
                },
                {
                    "name": "-mmpy-option=_",
                    "content": "Compile  ARCv2  code  with  a multiplier design option.  You can specify the option using\neither a string or numeric value for multo.  wlh1 is the default value.   The  recognized\nvalues are:\n\n0\nnone\nNo multiplier available.\n\n1\nw   16x16  multiplier,  fully  pipelined.  The following instructions are enabled: \"mpyw\"\nand \"mpyuw\".\n\n2\nwlh1\n32x32  multiplier,  fully  pipelined  (1  stage).   The  following  instructions  are\nadditionally enabled: \"mpy\", \"mpyu\", \"mpym\", \"mpymu\", and \"mpys\".\n\n3\nwlh2\n32x32  multiplier,  fully  pipelined  (2  stages).   The  following  instructions are\nadditionally enabled: \"mpy\", \"mpyu\", \"mpym\", \"mpymu\", and \"mpys\".\n\n4\nwlh3\nTwo  16x16  multipliers,  blocking,  sequential.   The  following  instructions   are\nadditionally enabled: \"mpy\", \"mpyu\", \"mpym\", \"mpymu\", and \"mpys\".\n\n5\nwlh4\nOne   16x16   multiplier,  blocking,  sequential.   The  following  instructions  are\nadditionally enabled: \"mpy\", \"mpyu\", \"mpym\", \"mpymu\", and \"mpys\".\n\n6\nwlh5\nOne  32x4  multiplier,  blocking,  sequential.   The   following   instructions   are\nadditionally enabled: \"mpy\", \"mpyu\", \"mpym\", \"mpymu\", and \"mpys\".\n\n7\nplusdmpy\nARC HS SIMD support.\n\n8\nplusmacd\nARC HS SIMD support.\n\n9\nplusqmacw\nARC HS SIMD support.\n\nThis option is only available for ARCv2 cores.\n"
                },
                {
                    "name": "-mfpu=_",
                    "content": "Enables  support  for  specific  floating-point  hardware  extensions  for  ARCv2  cores.\nSupported values for fpu are:\n\nfpus\nEnables support for single-precision floating-point hardware extensions.\n\nfpud\nEnables support for double-precision floating-point hardware extensions.  The single-\nprecision floating-point extension is also enabled.  Not available for ARC EM.\n\nfpuda\nEnables support for double-precision floating-point hardware extensions using double-\nprecision assist instructions.  The single-precision floating-point extension is also\nenabled.  This option is only available for ARC EM.\n\nfpudadiv\nEnables support for double-precision floating-point hardware extensions using double-\nprecision assist instructions.  The single-precision floating-point, square-root, and\ndivide extensions are also enabled.  This option is only available for ARC EM.\n\nfpudafma\nEnables support for double-precision floating-point hardware extensions using double-\nprecision  assist  instructions.   The  single-precision  floating-point  and   fused\nmultiply and add hardware extensions are also enabled.  This option is only available\nfor ARC EM.\n\nfpudaall\nEnables support for double-precision floating-point hardware extensions using double-\nprecision   assist   instructions.    All  single-precision  floating-point  hardware\nextensions are also enabled.  This option is only available for ARC EM.\n\nfpusdiv\nEnables support for single-precision floating-point, square-root and divide  hardware\nextensions.\n\nfpuddiv\nEnables  support for double-precision floating-point, square-root and divide hardware\nextensions.  This option includes option fpusdiv. Not available for ARC EM.\n\nfpusfma\nEnables support for  single-precision  floating-point  and  fused  multiply  and  add\nhardware extensions.\n\nfpudfma\nEnables  support  for  double-precision  floating-point  and  fused  multiply and add\nhardware extensions.  This option includes option fpusfma.  Not  available  for  ARC\nEM.\n\nfpusall\nEnables support for all single-precision floating-point hardware extensions.\n\nfpudall\nEnables   support  for  all  single-  and  double-precision  floating-point  hardware\nextensions.  Not available for ARC EM.\n"
                },
                {
                    "name": "-mirq-ctrl-saved=_",
                    "content": "Specifies general-purposes registers that the processor automatically  saves/restores  on\ninterrupt  entry  and  exit.  register-range is specified as two registers separated by a\ndash.  The register range always starts with \"r0\", the  upper  limit  is  \"fp\"  register.\nblink and lpcount are optional.  This option is only valid for ARC EM and ARC HS cores.\n"
                },
                {
                    "name": "-mrgf-banked-regs=_",
                    "content": "Specifies  the  number  of  registers replicated in second register bank on entry to fast\ninterrupt.  Fast interrupts are interrupts with the highest  priority  level  P0.   These\ninterrupts  save  only  PC  and  STATUS32  registers  to avoid memory transactions during\ninterrupt entry and exit sequences.  Use this option when you are using  fast  interrupts\nin an ARC V2 family processor.  Permitted values are 4, 8, 16, and 32.\n"
                },
                {
                    "name": "-mlpc-width=_",
                    "content": "Specify  the width of the \"lpcount\" register.  Valid values for width are 8, 16, 20, 24,\n28 and 32 bits.  The default width is fixed to 32 bits.  If the width is  less  than  32,\nthe  compiler  does  not attempt to transform loops in your program to use the zero-delay\nloop mechanism unless it is known that the \"lpcount\"  register  can  hold  the  required\nloop-counter  value.  Depending on the width specified, the compiler and run-time library\nmight continue to use the loop mechanism for various needs.  This  option  defines  macro\n\"ARCLPCWIDTH\" with the value of width.\n"
                },
                {
                    "name": "-mrf16",
                    "content": "This  option  instructs the compiler to generate code for a 16-entry register file.  This\noption defines the \"ARCRF16\" preprocessor macro.\n"
                },
                {
                    "name": "-mbranch-index",
                    "content": "Enable use of \"bi\" or \"bih\" instructions to implement jump tables.\n\nThe following options are passed through to the assembler, and also define preprocessor macro\nsymbols.\n"
                },
                {
                    "name": "-mdsp-packa",
                    "content": "Passed down to the assembler to  enable  the  DSP  Pack  A  extensions.   Also  sets  the\npreprocessor symbol \"Xdsppacka\".  This option is deprecated.\n"
                },
                {
                    "name": "-mdvbf",
                    "content": "Passed  down  to the assembler to enable the dual Viterbi butterfly extension.  Also sets\nthe preprocessor symbol \"Xdvbf\".  This option is deprecated.\n"
                },
                {
                    "name": "-mlock",
                    "content": "Passed down to the assembler to enable the locked load/store conditional extension.  Also\nsets the preprocessor symbol \"Xlock\".\n"
                },
                {
                    "name": "-mmac-d16",
                    "content": "Passed down to the assembler.  Also sets the  preprocessor  symbol  \"Xxmacd16\".   This\noption is deprecated.\n"
                },
                {
                    "name": "-mmac-24",
                    "content": "Passed  down  to  the  assembler.   Also sets the preprocessor symbol \"Xxmac24\".  This\noption is deprecated.\n"
                },
                {
                    "name": "-mrtsc",
                    "content": "Passed  down  to  the  assembler  to  enable  the  64-bit  time-stamp  counter  extension\ninstruction.  Also sets the preprocessor symbol \"Xrtsc\".  This option is deprecated.\n"
                },
                {
                    "name": "-mswape",
                    "content": "Passed  down  to  the  assembler  to enable the swap byte ordering extension instruction.\nAlso sets the preprocessor symbol \"Xswape\".\n"
                },
                {
                    "name": "-mtelephony",
                    "content": "Passed down to  the  assembler  to  enable  dual-  and  single-operand  instructions  for\ntelephony.  Also sets the preprocessor symbol \"Xtelephony\".  This option is deprecated.\n"
                },
                {
                    "name": "-mxy",
                    "content": "Passed  down  to  the  assembler  to  enable  the  XY  memory  extension.   Also sets the\npreprocessor symbol \"Xxy\".\n\nThe following options control how the assembly code is annotated:\n"
                },
                {
                    "name": "-misize",
                    "content": "Annotate assembler instructions with estimated addresses.\n"
                },
                {
                    "name": "-mannotate-align",
                    "content": "Explain what alignment considerations lead to the decision to make an  instruction  short\nor long.\n\nThe following options are passed through to the linker:\n"
                },
                {
                    "name": "-marclinux",
                    "content": "Passed through to the linker, to specify use of the \"arclinux\" emulation.  This option is\nenabled  by  default in tool chains built for \"arc-linux-uclibc\" and \"arceb-linux-uclibc\"\ntargets when profiling is not requested.\n"
                },
                {
                    "name": "-marclinux_prof",
                    "content": "Passed through to the linker, to specify use  of  the  \"arclinuxprof\"  emulation.   This\noption   is   enabled  by  default  in  tool  chains  built  for  \"arc-linux-uclibc\"  and\n\"arceb-linux-uclibc\" targets when profiling is requested.\n\nThe following options control the semantics of generated code:\n"
                },
                {
                    "name": "-mlong-calls",
                    "content": "Generate calls as register indirect calls, thus  providing  access  to  the  full  32-bit\naddress range.\n"
                },
                {
                    "name": "-mmedium-calls",
                    "content": "Don't  use less than 25-bit addressing range for calls, which is the offset available for\nan unconditional branch-and-link instruction.  Conditional execution of function calls is\nsuppressed, to allow use  of  the  25-bit  range,  rather  than  the  21-bit  range  with\nconditional   branch-and-link.    This   is   the  default  for  tool  chains  built  for\n\"arc-linux-uclibc\" and \"arceb-linux-uclibc\" targets.\n"
                },
                {
                    "name": "-G _",
                    "content": "Put definitions of externally-visible data in a small data section if  that  data  is  no\nbigger  than  num  bytes.   The default value of num is 4 for any ARC configuration, or 8\nwhen we have double load/store operations.\n",
                    "flag": "-G"
                },
                {
                    "name": "-mno-sdata",
                    "content": "Do not generate sdata references.   This  is  the  default  for  tool  chains  built  for\n\"arc-linux-uclibc\" and \"arceb-linux-uclibc\" targets.\n"
                },
                {
                    "name": "-mvolatile-cache",
                    "content": "Use ordinarily cached memory accesses for volatile references.  This is the default.\n"
                },
                {
                    "name": "-mno-volatile-cache",
                    "content": "Enable cache bypass for volatile references.\n\nThe following options fine tune code generation:\n"
                },
                {
                    "name": "-malign-call",
                    "content": "Does nothing.  Preserved for backward compatibility.\n"
                },
                {
                    "name": "-mauto-modify-reg",
                    "content": "Enable the use of pre/post modify with register displacement.\n"
                },
                {
                    "name": "-mbbit-peephole",
                    "content": "Enable bbit peephole2.\n"
                },
                {
                    "name": "-mno-brcc",
                    "content": "This  option  disables a target-specific pass in arcreorg to generate compare-and-branch\n(\"brcc\") instructions.  It has no effect on generation of these  instructions  driven  by\nthe combiner pass.\n"
                },
                {
                    "name": "-mcase-vector-pcrel",
                    "content": "Use  PC-relative switch case tables to enable case table shortening.  This is the default\nfor -Os.\n"
                },
                {
                    "name": "-mcompact-casesi",
                    "content": "Enable compact \"casesi\" pattern.  This is the default for -Os,  and  only  available  for\nARCv1 cores.  This option is deprecated.\n"
                },
                {
                    "name": "-mno-cond-exec",
                    "content": "Disable the ARCompact-specific pass to generate conditional execution instructions.\n\nDue  to  delay  slot  scheduling and interactions between operand numbers, literal sizes,\ninstruction lengths, and the support for conditional  execution,  the  target-independent\npass  to  generate  conditional  execution  is  often lacking, so the ARC port has kept a\nspecial  pass  around  that  tries  to  find  more   conditional   execution   generation\nopportunities  after  register  allocation,  branch shortening, and delay slot scheduling\nhave been done.  This pass generally, but not always, improves performance and code size,\nat the cost of extra compilation time, which is why there is an option to switch it  off.\nIf  you  have  a  problem  with  call instructions exceeding their allowable offset range\nbecause they are conditionalized, you should consider using -mmedium-calls instead.\n"
                },
                {
                    "name": "-mearly-cbranchsi",
                    "content": "Enable pre-reload use of the \"cbranchsi\" pattern.\n"
                },
                {
                    "name": "-mexpand-adddi",
                    "content": "Expand \"adddi3\" and \"subdi3\" at RTL generation time into \"add.f\", \"adc\" etc.  This option\nis deprecated.\n"
                },
                {
                    "name": "-mindexed-loads",
                    "content": "Enable the use of indexed loads.  This can be problematic because  some  optimizers  then\nassume that indexed stores exist, which is not the case.\n"
                },
                {
                    "name": "-mlra",
                    "content": "Enable  Local Register Allocation.  This is still experimental for ARC, so by default the\ncompiler uses standard reload (i.e. -mno-lra).\n"
                },
                {
                    "name": "-mlra-priority-none",
                    "content": "Don't indicate any priority for target registers.\n"
                },
                {
                    "name": "-mlra-priority-compact",
                    "content": "Indicate target register priority for r0..r3 / r12..r15.\n"
                },
                {
                    "name": "-mlra-priority-noncompact",
                    "content": "Reduce target register priority for r0..r3 / r12..r15.\n"
                },
                {
                    "name": "-mmillicode",
                    "content": "When optimizing for size (using -Os), prologues  and  epilogues  that  have  to  save  or\nrestore  a  large  number  of  registers  are  often shortened by using call to a special\nfunction in libgcc; this is referred to as a millicode call.  As  these  calls  can  pose\nperformance  issues,  and/or cause linking issues when linking in a nonstandard way, this\noption is provided to turn on or off millicode call generation.\n"
                },
                {
                    "name": "-mcode-density-frame",
                    "content": "This option enable  the  compiler  to  emit  \"enter\"  and  \"leave\"  instructions.   These\ninstructions are only valid for CPUs with code-density feature.\n"
                },
                {
                    "name": "-mmixed-code",
                    "content": "Does nothing.  Preserved for backward compatibility.\n"
                },
                {
                    "name": "-mq-class",
                    "content": "Ths  option  is  deprecated.  Enable q instruction alternatives.  This is the default for\n-Os.\n"
                },
                {
                    "name": "-mRcq",
                    "content": "Does nothing.  Preserved for backward compatibility.\n"
                },
                {
                    "name": "-mRcw",
                    "content": "Does nothing.  Preserved for backward compatibility.\n"
                },
                {
                    "name": "-msize-level=_",
                    "content": "Fine-tune size optimization with regards  to  instruction  lengths  and  alignment.   The\nrecognized values for level are:\n\n0   No size optimization.  This level is deprecated and treated like 1.\n\n1   Short instructions are used opportunistically.\n\n2   In addition, alignment of loops and of code after barriers are dropped.\n\n3   In addition, optional data alignment is dropped, and the option Os is enabled.\n\nThis  defaults  to 3 when -Os is in effect.  Otherwise, the behavior when this is not set\nis equivalent to level 1.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "Set instruction scheduling parameters for cpu, overriding any implied by -mcpu=.\n\nSupported values for cpu are\n\nARC600\nTune for ARC600 CPU.\n\nARC601\nTune for ARC601 CPU.\n\nARC700\nTune for ARC700 CPU with standard multiplier block.\n\nARC700-xmac\nTune for ARC700 CPU with XMAC block.\n\nARC725D\nTune for ARC725D CPU.\n\nARC750D\nTune for ARC750D CPU.\n\ncore3\nTune for ARCv2 core3 type CPU.  This option enable usage of \"dbnz\" instruction.\n\nrelease31a\nTune for ARC4x release 3.10a.\n"
                },
                {
                    "name": "-mmultcost=_",
                    "content": "Cost to assume for a multiply instruction, with 4 being equal to a normal instruction.\n"
                },
                {
                    "name": "-munalign-prob-threshold=_",
                    "content": "Does nothing.  Preserved for backward compatibility.\n\nThe following options are maintained for backward compatibility, but are now  deprecated  and\nwill be removed in a future release:\n"
                },
                {
                    "name": "-margonaut",
                    "content": "Obsolete FPX.\n"
                },
                {
                    "name": "-mbig-endian",
                    "content": ""
                },
                {
                    "name": "-EB",
                    "content": "code  is  supported  by  configuring  GCC to build \"arceb-elf32\" and \"arceb-linux-uclibc\"\ntargets, for which big endian is the default.\n"
                },
                {
                    "name": "-mlittle-endian",
                    "content": ""
                },
                {
                    "name": "-EL",
                    "content": "endian code is supported by configuring GCC to build \"arc-elf32\"  and  \"arc-linux-uclibc\"\ntargets, for which little endian is the default.\n"
                },
                {
                    "name": "-mbarrel_shifter",
                    "content": "Replaced by -mbarrel-shifter.\n"
                },
                {
                    "name": "-mdpfp_compact",
                    "content": "Replaced by -mdpfp-compact.\n"
                },
                {
                    "name": "-mdpfp_fast",
                    "content": "Replaced by -mdpfp-fast.\n"
                },
                {
                    "name": "-mdsp_packa",
                    "content": "Replaced by -mdsp-packa.\n"
                },
                {
                    "name": "-mEA",
                    "content": "Replaced by -mea.\n"
                },
                {
                    "name": "-mmac_24",
                    "content": "Replaced by -mmac-24.\n"
                },
                {
                    "name": "-mmac_d16",
                    "content": "Replaced by -mmac-d16.\n"
                },
                {
                    "name": "-mspfp_compact",
                    "content": "Replaced by -mspfp-compact.\n"
                },
                {
                    "name": "-mspfp_fast",
                    "content": "Replaced by -mspfp-fast.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "Values  arc600,  arc601,  arc700  and arc700-xmac for cpu are replaced by ARC600, ARC601,\nARC700 and ARC700-xmac respectively.\n"
                },
                {
                    "name": "-multcost=_",
                    "content": "Replaced by -mmultcost.\n\nARM Options\n\nThese -m options are defined for the ARM port:\n"
                },
                {
                    "name": "-mabi=_",
                    "content": "Generate code for the specified ABI.  Permissible values  are:  apcs-gnu,  atpcs,  aapcs,\naapcs-linux and iwmmxt.\n"
                },
                {
                    "name": "-mapcs-frame",
                    "content": "Generate  a  stack  frame  that is compliant with the ARM Procedure Call Standard for all\nfunctions, even if this is not strictly necessary for  correct  execution  of  the  code.\nSpecifying  -fomit-frame-pointer  with  this  option  causes  the  stack frames not to be\ngenerated  for  leaf  functions.   The  default  is  -mno-apcs-frame.   This  option   is\ndeprecated.\n"
                },
                {
                    "name": "-mapcs",
                    "content": "This is a synonym for -mapcs-frame and is deprecated.\n"
                },
                {
                    "name": "-mthumb-interwork",
                    "content": "Generate  code that supports calling between the ARM and Thumb instruction sets.  Without\nthis option, on pre-v5 architectures, the two instruction sets cannot  be  reliably  used\ninside  one  program.  The default is -mno-thumb-interwork, since slightly larger code is\ngenerated when -mthumb-interwork is specified.  In AAPCS configurations  this  option  is\nmeaningless.\n"
                },
                {
                    "name": "-mno-sched-prolog",
                    "content": "Prevent  the reordering of instructions in the function prologue, or the merging of those\ninstruction with the instructions in the function's body.  This means that all  functions\nstart  with  a  recognizable set of instructions (or in fact one of a choice from a small\nset of different function prologues), and this information can  be  used  to  locate  the\nstart of functions inside an executable piece of code.  The default is -msched-prolog.\n"
                },
                {
                    "name": "-mfloat-abi=_",
                    "content": "Specifies  which  floating-point  ABI  to  use.  Permissible values are: soft, softfp and\nhard.\n\nSpecifying soft causes GCC to generate output containing library calls for floating-point\noperations.   softfp  allows  the  generation  of  code  using  hardware   floating-point\ninstructions,  but still uses the soft-float calling conventions.  hard allows generation\nof floating-point instructions and uses FPU-specific calling conventions.\n\nThe default depends on the specific target configuration.  Note that the  hard-float  and\nsoft-float  ABIs  are  not link-compatible; you must compile your entire program with the\nsame ABI, and link with a compatible set of libraries.\n"
                },
                {
                    "name": "-mgeneral-regs-only",
                    "content": "Generate code which uses only the  general-purpose  registers.   This  will  prevent  the\ncompiler  from  using  floating-point and Advanced SIMD registers but will not impose any\nrestrictions on the assembler.\n"
                },
                {
                    "name": "-mlittle-endian",
                    "content": "Generate code for a processor running in little-endian mode.  This is the default for all\nstandard configurations.\n"
                },
                {
                    "name": "-mbig-endian",
                    "content": "Generate code for a processor running in big-endian mode; the default is to compile  code\nfor a little-endian processor.\n"
                },
                {
                    "name": "-mbe8",
                    "content": ""
                },
                {
                    "name": "-mbe32",
                    "content": "When  linking  a big-endian image select between BE8 and BE32 formats.  The option has no\neffect for little-endian images and is ignored.  The default is dependent on the selected\ntarget architecture.  For ARMv6 and later architectures the default  is  BE8,  for  older\narchitectures the default is BE32.  BE32 format has been deprecated by ARM.\n"
                },
                {
                    "name": "-march=_",
                    "content": "This  specifies the name of the target ARM architecture.  GCC uses this name to determine\nwhat kind of instructions it can emit when generating assembly code.  This option can  be\nused in conjunction with or instead of the -mcpu= option.\n\nPermissible  names are: armv4t, armv5t, armv5te, armv6, armv6j, armv6k, armv6kz, armv6t2,\narmv6z, armv6zk, armv7,  armv7-a,  armv7ve,  armv8-a,  armv8.1-a,  armv8.2-a,  armv8.3-a,\narmv8.4-a,  armv8.5-a,  armv8.6-a, armv9-a, armv7-r, armv8-r, armv6-m, armv6s-m, armv7-m,\narmv7e-m, armv8-m.base, armv8-m.main, armv8.1-m.main, armv9-a, iwmmxt and iwmmxt2.\n\nAdditionally, the following architectures, which lack support  for  the  Thumb  execution\nstate, are recognized but support is deprecated: armv4.\n\nMany of the architectures support extensions.  These can be added by appending +extension\nto  the  architecture  name.   Extension  options are processed in order and capabilities\naccumulate.  An extension will also enable any necessary base extensions  upon  which  it\ndepends.  For example, the +crypto extension will always enable the +simd extension.  The\nexception  to  the additive construction is for extensions that are prefixed with +no...:\nthese extensions disable the specified option and any other extensions that may depend on\nthe presence of that extension.\n\nFor example, -march=armv7-a+simd+nofp+vfpv4 is equivalent to writing -march=armv7-a+vfpv4\nsince the +simd option is entirely disabled by the +nofp option that follows it.\n\nMost extension names are generically named, but have an effect that is dependent upon the\narchitecture to which it is applied.  For example, the +simd option  can  be  applied  to\nboth  armv7-a  and  armv8-a  architectures, but will enable the original ARMv7-A Advanced\nSIMD (Neon) extensions for armv7-a and the ARMv8-A variant for armv8-a.\n\nThe table below lists the supported extensions for each architecture.  Architectures  not\nmentioned do not support any extensions.\n\narmv5te\narmv6\narmv6j\narmv6k\narmv6kz\narmv6t2\narmv6z\narmv6zk\n+fp The  VFPv2  floating-point  instructions.  The extension +vfpv2 can be used as an\nalias for this extension.\n\n+nofp\nDisable the floating-point instructions.\n\narmv7\nThe common subset of the ARMv7-A, ARMv7-R and ARMv7-M architectures.\n\n+fp The VFPv3 floating-point instructions, with 16 double-precision  registers.   The\nextension  +vfpv3-d16  can  be  used  as  an alias for this extension.  Note that\nfloating-point is  not  supported  by  the  base  ARMv7-M  architecture,  but  is\ncompatible with both the ARMv7-A and ARMv7-R architectures.\n\n+nofp\nDisable the floating-point instructions.\n\narmv7-a\n+mp The multiprocessing extension.\n\n+sec\nThe security extension.\n\n+fp The  VFPv3  floating-point instructions, with 16 double-precision registers.  The\nextension +vfpv3-d16 can be used as an alias for this extension.\n\n+simd\nThe Advanced SIMD (Neon) v1  and  the  VFPv3  floating-point  instructions.   The\nextensions +neon and +neon-vfpv3 can be used as aliases for this extension.\n\n+vfpv3\nThe VFPv3 floating-point instructions, with 32 double-precision registers.\n\n+vfpv3-d16-fp16\nThe VFPv3 floating-point instructions, with 16 double-precision registers and the\nhalf-precision floating-point conversion operations.\n\n+vfpv3-fp16\nThe VFPv3 floating-point instructions, with 32 double-precision registers and the\nhalf-precision floating-point conversion operations.\n\n+vfpv4-d16\nThe VFPv4 floating-point instructions, with 16 double-precision registers.\n\n+vfpv4\nThe VFPv4 floating-point instructions, with 32 double-precision registers.\n\n+neon-fp16\nThe  Advanced  SIMD (Neon) v1 and the VFPv3 floating-point instructions, with the\nhalf-precision floating-point conversion operations.\n\n+neon-vfpv4\nThe Advanced SIMD (Neon) v2 and the VFPv4 floating-point instructions.\n\n+nosimd\nDisable the Advanced SIMD instructions (does not disable floating point).\n\n+nofp\nDisable the floating-point and Advanced SIMD instructions.\n\narmv7ve\nThe extended version of the ARMv7-A architecture with support for virtualization.\n\n+fp The VFPv4 floating-point instructions, with 16 double-precision  registers.   The\nextension +vfpv4-d16 can be used as an alias for this extension.\n\n+simd\nThe  Advanced  SIMD  (Neon)  v2  and  the VFPv4 floating-point instructions.  The\nextension +neon-vfpv4 can be used as an alias for this extension.\n\n+vfpv3-d16\nThe VFPv3 floating-point instructions, with 16 double-precision registers.\n\n+vfpv3\nThe VFPv3 floating-point instructions, with 32 double-precision registers.\n\n+vfpv3-d16-fp16\nThe VFPv3 floating-point instructions, with 16 double-precision registers and the\nhalf-precision floating-point conversion operations.\n\n+vfpv3-fp16\nThe VFPv3 floating-point instructions, with 32 double-precision registers and the\nhalf-precision floating-point conversion operations.\n\n+vfpv4-d16\nThe VFPv4 floating-point instructions, with 16 double-precision registers.\n\n+vfpv4\nThe VFPv4 floating-point instructions, with 32 double-precision registers.\n\n+neon\nThe Advanced SIMD (Neon) v1  and  the  VFPv3  floating-point  instructions.   The\nextension +neon-vfpv3 can be used as an alias for this extension.\n\n+neon-fp16\nThe  Advanced  SIMD (Neon) v1 and the VFPv3 floating-point instructions, with the\nhalf-precision floating-point conversion operations.\n\n+nosimd\nDisable the Advanced SIMD instructions (does not disable floating point).\n\n+nofp\nDisable the floating-point and Advanced SIMD instructions.\n\narmv8-a\n+crc\nThe Cyclic Redundancy Check (CRC) instructions.\n\n+simd\nThe ARMv8-A Advanced SIMD and floating-point instructions.\n\n+crypto\nThe cryptographic instructions.\n\n+nocrypto\nDisable the cryptographic instructions.\n\n+nofp\nDisable the floating-point, Advanced SIMD and cryptographic instructions.\n\n+sb Speculation Barrier Instruction.\n\n+predres\nExecution and Data Prediction Restriction Instructions.\n\narmv8.1-a\n+simd\nThe ARMv8.1-A Advanced SIMD and floating-point instructions.\n\n+crypto\nThe  cryptographic  instructions.   This  also  enables  the  Advanced  SIMD  and\nfloating-point instructions.\n\n+nocrypto\nDisable the cryptographic instructions.\n\n+nofp\nDisable the floating-point, Advanced SIMD and cryptographic instructions.\n\n+sb Speculation Barrier Instruction.\n\n+predres\nExecution and Data Prediction Restriction Instructions.\n\narmv8.2-a\narmv8.3-a\n+fp16\nThe  half-precision  floating-point  data  processing  instructions.   This  also\nenables the Advanced SIMD and floating-point instructions.\n\n+fp16fml\nThe half-precision floating-point fmla extension.  This also  enables  the  half-\nprecision   floating-point   extension   and  Advanced  SIMD  and  floating-point\ninstructions.\n\n+simd\nThe ARMv8.1-A Advanced SIMD and floating-point instructions.\n\n+crypto\nThe  cryptographic  instructions.   This  also  enables  the  Advanced  SIMD  and\nfloating-point instructions.\n\n+dotprod\nEnable the Dot Product extension.  This also enables Advanced SIMD instructions.\n\n+nocrypto\nDisable the cryptographic extension.\n\n+nofp\nDisable the floating-point, Advanced SIMD and cryptographic instructions.\n\n+sb Speculation Barrier Instruction.\n\n+predres\nExecution and Data Prediction Restriction Instructions.\n\n+i8mm\n8-bit  Integer Matrix Multiply instructions.  This also enables Advanced SIMD and\nfloating-point instructions.\n\n+bf16\nBrain half-precision floating-point instructions.   This  also  enables  Advanced\nSIMD and floating-point instructions.\n\narmv8.4-a\n+fp16\nThe  half-precision  floating-point  data  processing  instructions.   This  also\nenables the Advanced SIMD and floating-point instructions  as  well  as  the  Dot\nProduct extension and the half-precision floating-point fmla extension.\n\n+simd\nThe  ARMv8.3-A  Advanced  SIMD and floating-point instructions as well as the Dot\nProduct extension.\n\n+crypto\nThe  cryptographic  instructions.   This  also  enables  the  Advanced  SIMD  and\nfloating-point instructions as well as the Dot Product extension.\n\n+nocrypto\nDisable the cryptographic extension.\n\n+nofp\nDisable the floating-point, Advanced SIMD and cryptographic instructions.\n\n+sb Speculation Barrier Instruction.\n\n+predres\nExecution and Data Prediction Restriction Instructions.\n\n+i8mm\n8-bit  Integer Matrix Multiply instructions.  This also enables Advanced SIMD and\nfloating-point instructions.\n\n+bf16\nBrain half-precision floating-point instructions.   This  also  enables  Advanced\nSIMD and floating-point instructions.\n\narmv8.5-a\n+fp16\nThe  half-precision  floating-point  data  processing  instructions.   This  also\nenables the Advanced SIMD and floating-point instructions  as  well  as  the  Dot\nProduct extension and the half-precision floating-point fmla extension.\n\n+simd\nThe  ARMv8.3-A  Advanced  SIMD and floating-point instructions as well as the Dot\nProduct extension.\n\n+crypto\nThe  cryptographic  instructions.   This  also  enables  the  Advanced  SIMD  and\nfloating-point instructions as well as the Dot Product extension.\n\n+nocrypto\nDisable the cryptographic extension.\n\n+nofp\nDisable the floating-point, Advanced SIMD and cryptographic instructions.\n\n+i8mm\n8-bit  Integer Matrix Multiply instructions.  This also enables Advanced SIMD and\nfloating-point instructions.\n\n+bf16\nBrain half-precision floating-point instructions.   This  also  enables  Advanced\nSIMD and floating-point instructions.\n\narmv8.6-a\n+fp16\nThe  half-precision  floating-point  data  processing  instructions.   This  also\nenables the Advanced SIMD and floating-point instructions  as  well  as  the  Dot\nProduct extension and the half-precision floating-point fmla extension.\n\n+simd\nThe  ARMv8.3-A  Advanced  SIMD and floating-point instructions as well as the Dot\nProduct extension.\n\n+crypto\nThe  cryptographic  instructions.   This  also  enables  the  Advanced  SIMD  and\nfloating-point instructions as well as the Dot Product extension.\n\n+nocrypto\nDisable the cryptographic extension.\n\n+nofp\nDisable the floating-point, Advanced SIMD and cryptographic instructions.\n\n+i8mm\n8-bit  Integer Matrix Multiply instructions.  This also enables Advanced SIMD and\nfloating-point instructions.\n\n+bf16\nBrain half-precision floating-point instructions.   This  also  enables  Advanced\nSIMD and floating-point instructions.\n\narmv7-r\n+fp.sp\nThe  single-precision  VFPv3 floating-point instructions.  The extension +vfpv3xd\ncan be used as an alias for this extension.\n\n+fp The VFPv3 floating-point instructions with 16  double-precision  registers.   The\nextension +vfpv3-d16 can be used as an alias for this extension.\n\n+vfpv3xd-d16-fp16\nThe  single-precision  VFPv3 floating-point instructions with 16 double-precision\nregisters and the half-precision floating-point conversion operations.\n\n+vfpv3-d16-fp16\nThe VFPv3 floating-point instructions with 16 double-precision registers and  the\nhalf-precision floating-point conversion operations.\n\n+nofp\nDisable the floating-point extension.\n\n+idiv\nThe ARM-state integer division instructions.\n\n+noidiv\nDisable the ARM-state integer division extension.\n\narmv7e-m\n+fp The single-precision VFPv4 floating-point instructions.\n\n+fpv5\nThe single-precision FPv5 floating-point instructions.\n\n+fp.dp\nThe single- and double-precision FPv5 floating-point instructions.\n\n+nofp\nDisable the floating-point extensions.\n\narmv8.1-m.main\n+dsp\nThe DSP instructions.\n\n+mve\nThe M-Profile Vector Extension (MVE) integer instructions.\n\n+mve.fp\nThe  M-Profile Vector Extension (MVE) integer and single precision floating-point\ninstructions.\n\n+fp The single-precision floating-point instructions.\n\n+fp.dp\nThe single- and double-precision floating-point instructions.\n\n+nofp\nDisable the floating-point extension.\n\n+cdecp0, +cdecp1, ... , +cdecp7\nEnable the Custom Datapath Extension (CDE) on selected coprocessors according  to\nthe numbers given in the options in the range 0 to 7.\n\n+pacbti\nEnable the Pointer Authentication and Branch Target Identification Extension.\n\narmv8-m.main\n+dsp\nThe DSP instructions.\n\n+nodsp\nDisable the DSP extension.\n\n+fp The single-precision floating-point instructions.\n\n+fp.dp\nThe single- and double-precision floating-point instructions.\n\n+nofp\nDisable the floating-point extension.\n\n+cdecp0, +cdecp1, ... , +cdecp7\nEnable  the Custom Datapath Extension (CDE) on selected coprocessors according to\nthe numbers given in the options in the range 0 to 7.\n\narmv8-r\n+crc\nThe Cyclic Redundancy Check (CRC) instructions.\n\n+fp.sp\nThe single-precision FPv5 floating-point instructions.\n\n+simd\nThe ARMv8-A Advanced SIMD and floating-point instructions.\n\n+crypto\nThe cryptographic instructions.\n\n+nocrypto\nDisable the cryptographic instructions.\n\n+nofp\nDisable the floating-point, Advanced SIMD and cryptographic instructions.\n\n-march=native causes the compiler to auto-detect the architecture of the build  computer.\nAt  present,  this  feature is only supported on GNU/Linux, and not all architectures are\nrecognized.  If the auto-detect is unsuccessful the option has no effect.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "This option specifies the name of the target ARM processor for which GCC should tune  the\nperformance of the code.  For some ARM implementations better performance can be obtained\nby  using  this  option.   Permissible names are: arm7tdmi, arm7tdmi-s, arm710t, arm720t,\narm740t, strongarm,  strongarm110,  strongarm1100,  strongarm1110,  arm8,  arm810,  arm9,\narm9e,  arm920,  arm920t,  arm922t, arm946e-s, arm966e-s, arm968e-s, arm926ej-s, arm940t,\narm9tdmi, arm10tdmi,  arm1020t,  arm1026ej-s,  arm10e,  arm1020e,  arm1022e,  arm1136j-s,\narm1136jf-s,  mpcore,  mpcorenovfp, arm1156t2-s, arm1156t2f-s, arm1176jz-s, arm1176jzf-s,\ngeneric-armv7-a, cortex-a5,  cortex-a7,  cortex-a8,  cortex-a9,  cortex-a12,  cortex-a15,\ncortex-a17,  cortex-a32,  cortex-a35,  cortex-a53,  cortex-a55,  cortex-a57,  cortex-a72,\ncortex-a73, cortex-a75, cortex-a76, cortex-a76ae, cortex-a77,  cortex-a78,  cortex-a78ae,\ncortex-a78c,  cortex-a710,  ares, cortex-r4, cortex-r4f, cortex-r5, cortex-r7, cortex-r8,\ncortex-r52, cortex-r52plus, cortex-m0, cortex-m0plus,  cortex-m1,  cortex-m3,  cortex-m4,\ncortex-m7,   cortex-m23,  cortex-m33,  cortex-m35p,  cortex-m55,  cortex-m85,  cortex-x1,\ncortex-x1c,              cortex-m1.small-multiply,              cortex-m0.small-multiply,\ncortex-m0plus.small-multiply,    exynos-m1,    marvell-pj4,   neoverse-n1,   neoverse-n2,\nneoverse-v1, xscale, iwmmxt, iwmmxt2, ep9312, fa526,  fa626,  fa606te,  fa626te,  fmp626,\nfa726te, star-mc1, xgene1.\n\nAdditionally,  this  option  can specify that GCC should tune the performance of the code\nfor   a   big.LITTLE    system.     Permissible    names    are:    cortex-a15.cortex-a7,\ncortex-a17.cortex-a7,            cortex-a57.cortex-a53,            cortex-a72.cortex-a53,\ncortex-a72.cortex-a35,           cortex-a73.cortex-a53,            cortex-a75.cortex-a55,\ncortex-a76.cortex-a55.\n\n-mtune=generic-arch  specifies  that  GCC  should  tune  the  performance  for a blend of\nprocessors within architecture arch.  The aim is to generate code that run  well  on  the\ncurrent  most  popular processors, balancing between optimizations that benefit some CPUs\nin the range, and avoiding performance pitfalls of  other  CPUs.   The  effects  of  this\noption may change in future GCC versions as CPU models come and go.\n\n-mtune  permits  the  same  extension  options as -mcpu, but the extension options do not\naffect the tuning of the generated code.\n\n-mtune=native causes the compiler to auto-detect the  CPU  of  the  build  computer.   At\npresent,  this  feature  is  only  supported  on GNU/Linux, and not all architectures are\nrecognized.  If the auto-detect is unsuccessful the option has no effect.\n"
                },
                {
                    "name": "-mcpu=_",
                    "content": "This specifies the name of the target ARM processor.  GCC uses this name  to  derive  the\nname  of  the  target  ARM architecture (as if specified by -march) and the ARM processor\ntype for which to tune for performance (as if specified by -mtune).  Where this option is\nused in conjunction with -march  or  -mtune,  those  options  take  precedence  over  the\nappropriate part of this option.\n\nMany of the supported CPUs implement optional architectural extensions.  Where this is so\nthe  architectural  extensions  are normally enabled by default.  If implementations that\nlack the extension exist, then  the  extension  syntax  can  be  used  to  disable  those\nextensions  that  have  been  omitted.   For  floating-point  and  Advanced  SIMD  (Neon)\ninstructions, the settings of the options -mfloat-abi and -mfpu must also be  considered:\nfloating-point and Advanced SIMD instructions will only be used if -mfloat-abi is not set\nto  soft;  and any setting of -mfpu other than auto will override the available floating-\npoint and SIMD extension instructions.\n\nFor example, cortex-a9 can be found in three major  configurations:  integer  only,  with\njust  a  floating-point unit or with floating-point and Advanced SIMD.  The default is to\nenable all the instructions, but the extensions +nosimd and +nofp can be used to  disable\njust the SIMD or both the SIMD and floating-point instructions respectively.\n\nPermissible names for this option are the same as those for -mtune.\n\nThe following extension options are common to the listed CPUs:\n\n+nodsp\nDisable  the  DSP instructions on cortex-m33, cortex-m35p, cortex-m55 and cortex-m85.\nAlso disable the M-Profile  Vector  Extension  (MVE)  integer  and  single  precision\nfloating-point instructions on cortex-m55 and cortex-m85.\n\n+nopacbti\nDisable  the  Pointer  Authentication  and  Branch Target Identification Extension on\ncortex-m85.\n\n+nomve\nDisable the M-Profile Vector Extension (MVE) integer and single  precision  floating-\npoint instructions on cortex-m55 and cortex-m85.\n\n+nomve.fp\nDisable   the  M-Profile  Vector  Extension  (MVE)  single  precision  floating-point\ninstructions on cortex-m55 and cortex-m85.\n\n+cdecp0, +cdecp1, ... , +cdecp7\nEnable the Custom Datapath Extension (CDE) on selected coprocessors according to  the\nnumbers given in the options in the range 0 to 7 on cortex-m55.\n\n+nofp\nDisables  the  floating-point instructions on arm9e, arm946e-s, arm966e-s, arm968e-s,\narm10e, arm1020e, arm1022e, arm926ej-s, arm1026ej-s, cortex-r5, cortex-r7, cortex-r8,\ncortex-m4,  cortex-m7,  cortex-m33,  cortex-m35p  cortex-m4,  cortex-m7,  cortex-m33,\ncortex-m35p,  cortex-m55  and  cortex-m85.   Disables  the  floating-point  and  SIMD\ninstructions  on  generic-armv7-a,  cortex-a5,   cortex-a7,   cortex-a8,   cortex-a9,\ncortex-a12,   cortex-a15,   cortex-a17,  cortex-a15.cortex-a7,  cortex-a17.cortex-a7,\ncortex-a32, cortex-a35, cortex-a53 and cortex-a55.\n\n+nofp.dp\nDisables  the  double-precision  component  of  the  floating-point  instructions  on\ncortex-r5, cortex-r7, cortex-r8, cortex-r52, cortex-r52plus and cortex-m7.\n\n+nosimd\nDisables   the   SIMD  (but  not  floating-point)  instructions  on  generic-armv7-a,\ncortex-a5, cortex-a7 and cortex-a9.\n\n+crypto\nEnables  the  cryptographic  instructions  on  cortex-a32,  cortex-a35,   cortex-a53,\ncortex-a55,   cortex-a57,  cortex-a72,  cortex-a73,  cortex-a75,  exynos-m1,  xgene1,\ncortex-a57.cortex-a53,         cortex-a72.cortex-a53,          cortex-a73.cortex-a35,\ncortex-a73.cortex-a53 and cortex-a75.cortex-a55.\n\nAdditionally the generic-armv7-a pseudo target defaults to VFPv3 with 16 double-precision\nregisters.   It  supports  the  following  extension  options: mp, sec, vfpv3-d16, vfpv3,\nvfpv3-d16-fp16, vfpv3-fp16, vfpv4-d16, vfpv4, neon,  neon-vfpv3,  neon-fp16,  neon-vfpv4.\nThe meanings are the same as for the extensions to -march=armv7-a.\n\n-mcpu=generic-arch    is   also   permissible,   and   is   equivalent   to   -march=arch\n-mtune=generic-arch.  See -mtune for more information.\n\n-mcpu=native causes the compiler to auto-detect  the  CPU  of  the  build  computer.   At\npresent,  this  feature  is  only  supported  on GNU/Linux, and not all architectures are\nrecognized.  If the auto-detect is unsuccessful the option has no effect.\n"
                },
                {
                    "name": "-mfpu=_",
                    "content": "This specifies what floating-point hardware (or hardware emulation) is available  on  the\ntarget.    Permissible   names   are:   auto,   vfpv2,   vfpv3,   vfpv3-fp16,  vfpv3-d16,\nvfpv3-d16-fp16,  vfpv3xd,  vfpv3xd-fp16,   neon-vfpv3,   neon-fp16,   vfpv4,   vfpv4-d16,\nfpv4-sp-d16,    neon-vfpv4,    fpv5-d16,   fpv5-sp-d16,   fp-armv8,   neon-fp-armv8   and\ncrypto-neon-fp-armv8.  Note that neon is an alias for neon-vfpv3 and vfp is an alias  for\nvfpv2.\n\nThe  setting  auto  is  the default and is special.  It causes the compiler to select the\nfloating-point and Advanced SIMD instructions based on the settings of -mcpu and -march.\n\nIf the selected floating-point hardware includes the NEON  extension  (e.g.  -mfpu=neon),\nnote  that  floating-point  operations are not generated by GCC's auto-vectorization pass\nunless -funsafe-math-optimizations is also specified.  This is because NEON hardware does\nnot fully implement the IEEE 754 standard for floating-point  arithmetic  (in  particular\ndenormal  values are treated as zero), so the use of NEON instructions may lead to a loss\nof precision.\n\nYou can also set the fpu name at function level  by  using  the  target(\"fpu=\")  function\nattributes or pragmas.\n"
                },
                {
                    "name": "-mfp16-format=_",
                    "content": "Specify the format of the \"fp16\" half-precision floating-point type.  Permissible names\nare  none, ieee, and alternative; the default is none, in which case the \"fp16\" type is\nnot defined.\n"
                },
                {
                    "name": "-mstructure-size-boundary=_",
                    "content": "The sizes of all structures and unions are rounded up to a multiple of the number of bits\nset by this option.  Permissible values are 8, 32 and 64.  The default value  varies  for\ndifferent  toolchains.   For the COFF targeted toolchain the default value is 8.  A value\nof 64 is only allowed if the underlying ABI supports it.\n\nSpecifying a larger number can produce faster, more efficient code, but can also increase\nthe size of the program.  Different values are potentially incompatible.   Code  compiled\nwith  one  value  cannot  necessarily expect to work with code or libraries compiled with\nanother value, if they exchange information using structures or unions.\n\nThis option is deprecated.\n"
                },
                {
                    "name": "-mabort-on-noreturn",
                    "content": "Generate a call to the function \"abort\" at the end  of  a  \"noreturn\"  function.   It  is\nexecuted if the function tries to return.\n"
                },
                {
                    "name": "-mlong-calls",
                    "content": ""
                },
                {
                    "name": "-mno-long-calls",
                    "content": "Tells the compiler to perform function calls by first loading the address of the function\ninto  a  register and then performing a subroutine call on this register.  This switch is\nneeded if the target function lies outside of the 64-megabyte  addressing  range  of  the\noffset-based version of subroutine call instruction.\n\nEven  if  this switch is enabled, not all function calls are turned into long calls.  The\nheuristic is that static functions,  functions  that  have  the  \"shortcall\"  attribute,\nfunctions that are inside the scope of a \"#pragma nolongcalls\" directive, and functions\nwhose  definitions have already been compiled within the current compilation unit are not\nturned into long calls.  The exceptions to this rule are that weak function  definitions,\nfunctions  with  the \"longcall\" attribute or the \"section\" attribute, and functions that\nare within the scope of a \"#pragma longcalls\" directive  are  always  turned  into  long\ncalls.\n\nThis  feature is not enabled by default.  Specifying -mno-long-calls restores the default\nbehavior,  as  does  placing  the  function  calls  within  the  scope  of   a   \"#pragma\nlongcallsoff\"  directive.   Note  these  switches  have  no  effect on how the compiler\ngenerates code to handle function calls via function pointers.\n"
                },
                {
                    "name": "-msingle-pic-base",
                    "content": "Treat the register used for PIC addressing as read-only, rather than loading  it  in  the\nprologue  for  each  function.   The  runtime system is responsible for initializing this\nregister with an appropriate value before execution begins.\n"
                },
                {
                    "name": "-mpic-register=_",
                    "content": "Specify the register to be used for PIC addressing.  For  standard  PIC  base  case,  the\ndefault  is  any suitable register determined by compiler.  For single PIC base case, the\ndefault is R9 if target is EABI based or stack-checking is enabled, otherwise the default\nis R10.\n"
                },
                {
                    "name": "-mpic-data-is-text-relative",
                    "content": "Assume that the displacement between the text and data segments is fixed at  static  link\ntime.  This permits using PC-relative addressing operations to access data known to be in\nthe  data segment.  For non-VxWorks RTP targets, this option is enabled by default.  When\ndisabled on such targets, it will enable -msingle-pic-base by default.\n"
                },
                {
                    "name": "-mpoke-function-name",
                    "content": "Write the name of each function into the text section, directly  preceding  the  function\nprologue.  The generated code is similar to this:\n\nt0\n.ascii \"armpokefunctionname\", 0\n.align\nt1\n.word 0xff000000 + (t1 - t0)\narmpokefunctionname\nmov     ip, sp\nstmfd   sp!, {fp, ip, lr, pc}\nsub     fp, ip, #4\n\nWhen performing a stack backtrace, code can inspect the value of \"pc\" stored at \"fp + 0\".\nIf  the  trace function then looks at location \"pc - 12\" and the top 8 bits are set, then\nwe know that there is a function name embedded immediately preceding  this  location  and\nhas length \"((pc[-3]) & 0xff000000)\".\n"
                },
                {
                    "name": "-mthumb",
                    "content": ""
                },
                {
                    "name": "-marm",
                    "content": "Select  between  generating  code that executes in ARM and Thumb states.  The default for\nmost configurations is to generate code that executes in ARM state, but the  default  can\nbe changed by configuring GCC with the --with-mode=state configure option.\n\nYou  can  also  override  the  ARM  and  Thumb  mode  for  each  function  by  using  the\ntarget(\"thumb\") and target(\"arm\") function attributes or pragmas.\n"
                },
                {
                    "name": "-mflip-thumb",
                    "content": "Switch ARM/Thumb modes on alternating functions.  This option is provided for  regression\ntesting  of  mixed  Thumb/ARM  code  generation,  and is not intended for ordinary use in\ncompiling code.\n"
                },
                {
                    "name": "-mtpcs-frame",
                    "content": "Generate a stack frame that is compliant with the Thumb Procedure Call Standard  for  all\nnon-leaf  functions.   (A  leaf  function is one that does not call any other functions.)\nThe default is -mno-tpcs-frame.\n"
                },
                {
                    "name": "-mtpcs-leaf-frame",
                    "content": "Generate a stack frame that is compliant with the Thumb Procedure Call Standard  for  all\nleaf  functions.   (A  leaf function is one that does not call any other functions.)  The\ndefault is -mno-apcs-leaf-frame.\n"
                },
                {
                    "name": "-mcallee-super-interworking",
                    "content": "Gives all externally visible functions in the file being compiled an ARM instruction  set\nheader  which  switches  to  Thumb  mode before executing the rest of the function.  This\nallows these functions to be called from non-interworking code.  This option is not valid\nin AAPCS configurations because interworking is enabled by default.\n"
                },
                {
                    "name": "-mcaller-super-interworking",
                    "content": "Allows calls via function pointers (including virtual  functions)  to  execute  correctly\nregardless  of  whether the target code has been compiled for interworking or not.  There\nis a small overhead in the cost of  executing  a  function  pointer  if  this  option  is\nenabled.   This  option  is  not  valid  in  AAPCS configurations because interworking is\nenabled by default.\n"
                },
                {
                    "name": "-mtp=_",
                    "content": "Specify the access model for the thread local storage  pointer.   The  valid  models  are\nsoft,  which generates calls to \"aeabireadtp\", cp15, which fetches the thread pointer\nfrom \"cp15\" directly (supported in the arm6k architecture), and auto, which uses the best\navailable method for the selected processor.  The default setting is auto.\n"
                },
                {
                    "name": "-mtls-dialect=_",
                    "content": "Specify the dialect to  use  for  accessing  thread  local  storage.   Two  dialects  are\nsupported---gnu and gnu2.  The gnu dialect selects the original GNU scheme for supporting\nlocal and global dynamic TLS models.  The gnu2 dialect selects the GNU descriptor scheme,\nwhich  provides  better  performance  for shared libraries.  The GNU descriptor scheme is\ncompatible with the original scheme, but does require new assembler, linker  and  library\nsupport.   Initial and local exec TLS models are unaffected by this option and always use\nthe original scheme.\n"
                },
                {
                    "name": "-mword-relocations",
                    "content": "Only generate absolute relocations on word-sized  values  (i.e.  RARMABS32).   This  is\nenabled  by default on targets (uClinux, SymbianOS) where the runtime loader imposes this\nrestriction,  and  when  -fpic  or  -fPIC  is  specified.  This  option  conflicts   with\n-mslow-flash-data.\n"
                },
                {
                    "name": "-mfix-cortex-m3-ldrd",
                    "content": "Some  Cortex-M3 cores can cause data corruption when \"ldrd\" instructions with overlapping\ndestination  and  base  registers  are  used.   This  option  avoids   generating   these\ninstructions.  This option is enabled by default when -mcpu=cortex-m3 is specified.\n"
                },
                {
                    "name": "-mfix-cortex-a57-aes-1742098",
                    "content": ""
                },
                {
                    "name": "-mno-fix-cortex-a57-aes-1742098",
                    "content": ""
                },
                {
                    "name": "-mfix-cortex-a72-aes-1655431",
                    "content": ""
                },
                {
                    "name": "-mno-fix-cortex-a72-aes-1655431",
                    "content": "Enable  (disable) mitigation for an erratum on Cortex-A57 and Cortex-A72 that affects the\nAES  cryptographic  instructions.   This  option  is  enabled  by  default  when   either\n-mcpu=cortex-a57 or -mcpu=cortex-a72 is specified.\n"
                },
                {
                    "name": "-munaligned-access",
                    "content": ""
                },
                {
                    "name": "-mno-unaligned-access",
                    "content": "Enables  (or  disables) reading and writing of 16- and 32- bit values from addresses that\nare not 16- or 32- bit  aligned.   By  default  unaligned  access  is  disabled  for  all\npre-ARMv6,  all ARMv6-M and for ARMv8-M Baseline architectures, and enabled for all other\narchitectures.  If unaligned access is not enabled then words in packed  data  structures\nare accessed a byte at a time.\n\nThe  ARM  attribute  \"TagCPUunalignedaccess\"  is  set  in the generated object file to\neither true or false, depending upon the setting of this option.  If unaligned access  is\nenabled then the preprocessor symbol \"ARMFEATUREUNALIGNED\" is also defined.\n"
                },
                {
                    "name": "-mneon-for-64bits",
                    "content": "This option is deprecated and has no effect.\n"
                },
                {
                    "name": "-mslow-flash-data",
                    "content": "Assume  loading  data  from flash is slower than fetching instruction.  Therefore literal\nload is minimized for better performance.  This option is only supported  when  compiling\nfor ARMv7 M-profile and off by default. It conflicts with -mword-relocations.\n"
                },
                {
                    "name": "-masm-syntax-unified",
                    "content": "Assume  inline assembler is using unified asm syntax.  The default is currently off which\nimplies divided syntax.  This option has no impact on Thumb2. However, this may change in\nfuture releases of GCC.  Divided syntax should be considered deprecated.\n"
                },
                {
                    "name": "-mrestrict-it",
                    "content": "Restricts generation of IT blocks to conform to the rules of ARMv8-A.  IT blocks can only\ncontain a single 16-bit instruction from a select set of instructions. This option is  on\nby default for ARMv8-A Thumb mode.\n"
                },
                {
                    "name": "-mprint-tune-info",
                    "content": "Print  CPU  tuning information as comment in assembler file.  This is an option used only\nfor regression testing of the compiler and not intended for  ordinary  use  in  compiling\ncode.  This option is disabled by default.\n"
                },
                {
                    "name": "-mverbose-cost-dump",
                    "content": "Enable  verbose  cost model dumping in the debug dump files.  This option is provided for\nuse in debugging the compiler.\n"
                },
                {
                    "name": "-mpure-code",
                    "content": "Do not allow constant data to be placed in code sections.  Additionally,  when  compiling\nfor ELF object format give all text sections the ELF processor-specific section attribute\n\"SHFARMPURECODE\".   This  option  is  only  available  when generating non-pic code for\nM-profile targets.\n"
                },
                {
                    "name": "-mcmse",
                    "content": "Generate secure code as per the \"ARMv8-M Security Extensions: Requirements on Development\nTools     Engineering      Specification\",      which      can      be      found      on\n<https://developer.arm.com/documentation/ecm0359818/latest/>.\n"
                },
                {
                    "name": "-mfix-cmse-cve-2021-35465",
                    "content": "Mitigate  against  a  potential  security  issue  with  the  \"VLLDM\"  instruction in some\nM-profile devices when using CMSE (CVE-2021-365465).  This option is enabled  by  default\nwhen   the   option  -mcpu=  is  used  with  \"cortex-m33\",  \"cortex-m35p\",  \"cortex-m55\",\n\"cortex-m85\" or \"star-mc1\".  The  option  -mno-fix-cmse-cve-2021-35465  can  be  used  to\ndisable the mitigation.\n"
                },
                {
                    "name": "-mstack-protector-guard=_",
                    "content": ""
                },
                {
                    "name": "-mstack-protector-guard-offset=_",
                    "content": "Generate stack protection code using canary at guard.  Supported locations are global for\na  global  canary  or  tls  for  a  canary  accessible  via  the TLS register. The option\n-mstack-protector-guard-offset= is for use with -fstack-protector-guard=tls and  not  for\nuse in user-land code.\n"
                },
                {
                    "name": "-mfdpic",
                    "content": ""
                },
                {
                    "name": "-mno-fdpic",
                    "content": "Select  the  FDPIC  ABI,  which uses 64-bit function descriptors to represent pointers to\nfunctions.  When the compiler is configured for  \"arm-*-uclinuxfdpiceabi\"  targets,  this\noption  is  on  by  default  and  implies -fPIE if none of the PIC/PIE-related options is\nprovided.  On other targets, it only enables the FDPIC-specific code generation features,\nand the user should explicitly provide the PIC/PIE-related options as needed.\n\nNote that static linking is not supported because it  would  still  involve  the  dynamic\nlinker  when the program self-relocates.  If such behavior is acceptable, use -static and\n-Wl,-dynamic-linker options.\n\nThe opposite -mno-fdpic option is useful (and required) to build the Linux  kernel  using\nthe  same  (\"arm-*-uclinuxfdpiceabi\")  toolchain  as  the  one used to build the userland\nprograms.\n"
                },
                {
                    "name": "-mbranch-protection=_",
                    "content": "Enable branch protection features (armv8.1-m.main  only).   none  generate  code  without\nbranch  protection  or  return  address  signing.  standard[+leaf] generate code with all\nbranch protection features enabled at their standard level.  pac-ret[+leaf] generate code\nwith return address signing set to its standard level, which is  to  sign  all  functions\nthat  save  the  return  address to memory.  leaf When return address signing is enabled,\nalso sign leaf functions even if they do not write the return address  to  memory.   +bti\nAdd landing-pad instructions at the permitted targets of indirect branch instructions.\n\nIf  the  +pacbti  architecture  extension  is not enabled, then all branch protection and\nreturn address signing operations are constrained to use only the instructions defined in\nthe architectural-NOP space. The generated code  will  remain  backwards-compatible  with\nearlier  versions  of the architecture, but the additional security can be enabled at run\ntime on processors that support the PACBTI extension.\n\nBranch target enforcement using BTI can only be enabled at runtime if  all  code  in  the\napplication has been compiled with at least -mbranch-protection=bti.\n\nAny setting other than none is supported only on armv8-m.main or later.\n\nThe default is to generate code without branch protection or return address signing.\n\nAVR Options\n\nThese options are defined for AVR implementations:\n"
                },
                {
                    "name": "-mmcu=_",
                    "content": "Specify  the AVR instruction set architecture (ISA) or device type.  The default for this\noption is \"avr2\".\n\nThe following AVR devices and ISAs  are  supported.   Note:  A  complete  device  support\nconsists  of  startup  code  \"crtmcu.o\",  a  device  header \"avr/io*.h\", a device library\n\"libmcu.a\"  and  a  device-specs   (\"https://gcc.gnu.org/wiki/avr-gcc#spec-files\")   file\n\"specs-mcu\".  Only  the latter is provided by the compiler according the supported \"mcu\"s\nbelow.  The rest is supported by  AVR-LibC  (\"https://www.nongnu.org/avr-libc/\"),  or  by\nmeans  of  \"atpack\"  (\"https://gcc.gnu.org/wiki/avr-gcc#atpack\")  files from the hardware\nmanufacturer.\n\n\"avr2\"\n\"Classic\" devices with up to 8 KiB of program memory.  mcu = \"attiny22\",  \"attiny26\",\n\"at90s2313\",   \"at90s2323\",   \"at90s2333\",   \"at90s2343\",  \"at90s4414\",  \"at90s4433\",\n\"at90s4434\", \"at90c8534\", \"at90s8515\", \"at90s8535\".\n\n\"avr25\"\n\"Classic\" devices with up to 8 KiB of program memory and with the \"MOVW\" instruction.\nmcu = \"attiny13\",  \"attiny13a\",  \"attiny24\",  \"attiny24a\",  \"attiny25\",  \"attiny261\",\n\"attiny261a\",  \"attiny2313\",  \"attiny2313a\",  \"attiny43u\",  \"attiny44\",  \"attiny44a\",\n\"attiny45\",  \"attiny48\",  \"attiny441\",   \"attiny461\",   \"attiny461a\",   \"attiny4313\",\n\"attiny84\",    \"attiny84a\",    \"attiny85\",   \"attiny87\",   \"attiny88\",   \"attiny828\",\n\"attiny841\", \"attiny861\", \"attiny861a\", \"ata5272\", \"ata6616c\", \"at86rf401\".\n\n\"avr3\"\n\"Classic\" devices with 16 KiB up to 64 KiB of  program  memory.   mcu  =  \"at76c711\",\n\"at43usb355\".\n\n\"avr31\"\n\"Classic\" devices with 128 KiB of program memory.  mcu = \"atmega103\", \"at43usb320\".\n\n\"avr35\"\n\"Classic\"  devices  with  16  KiB  up to 64 KiB of program memory and with the \"MOVW\"\ninstruction.    mcu   =   \"attiny167\",   \"attiny1634\",   \"atmega8u2\",   \"atmega16u2\",\n\"atmega32u2\", \"ata5505\", \"ata6617c\", \"ata664251\", \"at90usb82\", \"at90usb162\".\n\n\"avr4\"\n\"Enhanced\"  devices  with  up  to  8  KiB  of  program  memory.   mcu  =  \"atmega48\",\n\"atmega48a\",  \"atmega48p\",   \"atmega48pa\",   \"atmega48pb\",   \"atmega8\",   \"atmega8a\",\n\"atmega8hva\",   \"atmega88\",  \"atmega88a\",  \"atmega88p\",  \"atmega88pa\",  \"atmega88pb\",\n\"atmega8515\", \"atmega8535\", \"ata5795\", \"ata6285\", \"ata6286\",  \"ata6289\",  \"ata6612c\",\n\"at90pwm1\", \"at90pwm2\", \"at90pwm2b\", \"at90pwm3\", \"at90pwm3b\", \"at90pwm81\".\n\n\"avr5\"\n\"Enhanced\"  devices  with  16  KiB up to 64 KiB of program memory.  mcu = \"atmega16\",\n\"atmega16a\",   \"atmega16hva\",   \"atmega16hva2\",   \"atmega16hvb\",   \"atmega16hvbrevb\",\n\"atmega16m1\",  \"atmega16u4\",  \"atmega161\",  \"atmega162\",  \"atmega163\",  \"atmega164a\",\n\"atmega164p\", \"atmega164pa\", \"atmega165\", \"atmega165a\", \"atmega165p\",  \"atmega165pa\",\n\"atmega168\",  \"atmega168a\",  \"atmega168p\", \"atmega168pa\", \"atmega168pb\", \"atmega169\",\n\"atmega169a\", \"atmega169p\",  \"atmega169pa\",  \"atmega32\",  \"atmega32a\",  \"atmega32c1\",\n\"atmega32hvb\",    \"atmega32hvbrevb\",    \"atmega32m1\",   \"atmega32u4\",   \"atmega32u6\",\n\"atmega323\", \"atmega324a\", \"atmega324p\", \"atmega324pa\",  \"atmega324pb\",  \"atmega325\",\n\"atmega325a\",  \"atmega325p\", \"atmega325pa\", \"atmega328\", \"atmega328p\", \"atmega328pb\",\n\"atmega329\", \"atmega329a\", \"atmega329p\", \"atmega329pa\", \"atmega3250\",  \"atmega3250a\",\n\"atmega3250p\",    \"atmega3250pa\",    \"atmega3290\",    \"atmega3290a\",   \"atmega3290p\",\n\"atmega3290pa\", \"atmega406\", \"atmega64\",  \"atmega64a\",  \"atmega64c1\",  \"atmega64hve\",\n\"atmega64hve2\", \"atmega64m1\", \"atmega64rfr2\", \"atmega640\", \"atmega644\", \"atmega644a\",\n\"atmega644p\",     \"atmega644pa\",    \"atmega644rfr2\",    \"atmega645\",    \"atmega645a\",\n\"atmega645p\", \"atmega649\", \"atmega649a\", \"atmega649p\",  \"atmega6450\",  \"atmega6450a\",\n\"atmega6450p\",  \"atmega6490\",  \"atmega6490a\",  \"atmega6490p\",  \"ata5790\", \"ata5790n\",\n\"ata5791\",  \"ata6613c\",  \"ata6614q\",  \"ata5782\",  \"ata5831\",  \"ata8210\",   \"ata8510\",\n\"ata5787\",   \"ata5835\",  \"ata5700m322\",  \"ata5702m322\",  \"at90pwm161\",  \"at90pwm216\",\n\"at90pwm316\", \"at90can32\",  \"at90can64\",  \"at90scr100\",  \"at90usb646\",  \"at90usb647\",\n\"at94k\", \"m3000\".\n\n\"avr51\"\n\"Enhanced\"  devices with 128 KiB of program memory.  mcu = \"atmega128\", \"atmega128a\",\n\"atmega128rfa1\",   \"atmega128rfr2\",   \"atmega1280\",    \"atmega1281\",    \"atmega1284\",\n\"atmega1284p\", \"atmega1284rfr2\", \"at90can128\", \"at90usb1286\", \"at90usb1287\".\n\n\"avr6\"\n\"Enhanced\"  devices  with  3-byte  PC, i.e. with more than 128 KiB of program memory.\nmcu = \"atmega256rfr2\", \"atmega2560\", \"atmega2561\", \"atmega2564rfr2\".\n\n\"avrxmega2\"\n\"XMEGA\" devices with more than 8 KiB and up to 64  KiB  of  program  memory.   mcu  =\n\"atxmega8e5\",    \"atxmega16a4\",    \"atxmega16a4u\",    \"atxmega16c4\",   \"atxmega16d4\",\n\"atxmega16e5\",   \"atxmega32a4\",   \"atxmega32a4u\",    \"atxmega32c3\",    \"atxmega32c4\",\n\"atxmega32d3\",  \"atxmega32d4\",  \"atxmega32e5\", \"avr64da28\", \"avr64da32\", \"avr64da48\",\n\"avr64da64\",  \"avr64db28\",  \"avr64db32\",   \"avr64db48\",   \"avr64db64\",   \"avr64dd14\",\n\"avr64dd20\",   \"avr64dd28\",   \"avr64dd32\",   \"avr64du28\",  \"avr64du32\",  \"avr64ea28\",\n\"avr64ea32\", \"avr64ea48\".\n\n\"avrxmega3\"\n\"XMEGA\" devices with up to 64 KiB of  combined  program  memory  and  RAM,  and  with\nprogram  memory  visible  in  the RAM address space.  mcu = \"attiny202\", \"attiny204\",\n\"attiny212\",  \"attiny214\",  \"attiny402\",   \"attiny404\",   \"attiny406\",   \"attiny412\",\n\"attiny414\",  \"attiny416\",  \"attiny416auto\",  \"attiny417\",  \"attiny424\", \"attiny426\",\n\"attiny427\",  \"attiny804\",  \"attiny806\",   \"attiny807\",   \"attiny814\",   \"attiny816\",\n\"attiny817\",   \"attiny824\",  \"attiny826\",  \"attiny827\",  \"attiny1604\",  \"attiny1606\",\n\"attiny1607\", \"attiny1614\", \"attiny1616\", \"attiny1617\",  \"attiny1624\",  \"attiny1626\",\n\"attiny1627\",  \"attiny3214\",  \"attiny3216\", \"attiny3217\", \"attiny3224\", \"attiny3226\",\n\"attiny3227\", \"atmega808\",  \"atmega809\",  \"atmega1608\",  \"atmega1609\",  \"atmega3208\",\n\"atmega3209\",  \"atmega4808\",  \"atmega4809\",  \"avr16dd14\",  \"avr16dd20\",  \"avr16dd28\",\n\"avr16dd32\",  \"avr16du14\",  \"avr16du20\",   \"avr16du28\",   \"avr16du32\",   \"avr16ea28\",\n\"avr16ea32\",   \"avr16ea48\",   \"avr16eb14\",   \"avr16eb20\",  \"avr16eb28\",  \"avr16eb32\",\n\"avr32da28\",  \"avr32da32\",  \"avr32da48\",   \"avr32db28\",   \"avr32db32\",   \"avr32db48\",\n\"avr32dd14\",   \"avr32dd20\",   \"avr32dd28\",   \"avr32dd32\",  \"avr32du14\",  \"avr32du20\",\n\"avr32du28\", \"avr32du32\", \"avr32ea28\", \"avr32ea32\", \"avr32ea48\".\n\n\"avrxmega4\"\n\"XMEGA\" devices with more than 64 KiB and up to 128 KiB of  program  memory.   mcu  =\n\"atxmega64a3\",    \"atxmega64a3u\",   \"atxmega64a4u\",   \"atxmega64b1\",   \"atxmega64b3\",\n\"atxmega64c3\",    \"atxmega64d3\",    \"atxmega64d4\",    \"avr128da28\",     \"avr128da32\",\n\"avr128da48\", \"avr128da64\", \"avr128db28\", \"avr128db32\", \"avr128db48\", \"avr128db64\".\n\n\"avrxmega5\"\n\"XMEGA\"  devices  with  more than 64 KiB and up to 128 KiB of program memory and more\nthan 64 KiB of RAM.  mcu = \"atxmega64a1\", \"atxmega64a1u\".\n\n\"avrxmega6\"\n\"XMEGA\" devices with more than 128 KiB of  program  memory.   mcu  =  \"atxmega128a3\",\n\"atxmega128a3u\",   \"atxmega128b1\",  \"atxmega128b3\",  \"atxmega128c3\",  \"atxmega128d3\",\n\"atxmega128d4\",  \"atxmega192a3\",  \"atxmega192a3u\",  \"atxmega192c3\",   \"atxmega192d3\",\n\"atxmega256a3\",  \"atxmega256a3b\",  \"atxmega256a3bu\", \"atxmega256a3u\", \"atxmega256c3\",\n\"atxmega256d3\", \"atxmega384c3\", \"atxmega384d3\".\n\n\"avrxmega7\"\n\"XMEGA\" devices with more than 128 KiB of program memory and more than 64 KiB of RAM.\nmcu = \"atxmega128a1\", \"atxmega128a1u\", \"atxmega128a4u\".\n\n\"avrtiny\"\n\"TINY\" Tiny core devices with 512 B up to 4 KiB of program memory.  mcu =  \"attiny4\",\n\"attiny5\", \"attiny9\", \"attiny10\", \"attiny102\", \"attiny104\", \"attiny20\", \"attiny40\".\n\n\"avr1\"\nThis  ISA  is  implemented  by the minimal AVR core and supported for assembler only.\nmcu = \"attiny11\", \"attiny12\", \"attiny15\", \"attiny28\", \"at90s1200\".\n"
                },
                {
                    "name": "-mabsdata",
                    "content": "Assume that all data in static storage can be accessed by LDS / STS  instructions.   This\noption  has only an effect on reduced Tiny devices like ATtiny40.  See also the \"absdata\"\nAVR Variable Attributes,variable attribute.\n"
                },
                {
                    "name": "-maccumulate-args",
                    "content": "Accumulate outgoing function arguments and acquire/release the  needed  stack  space  for\noutgoing  function  arguments  once  in function prologue/epilogue.  Without this option,\noutgoing arguments are pushed before calling a function and popped afterwards.\n\nPopping the  arguments  after  the  function  call  can  be  expensive  on  AVR  so  that\naccumulating the stack space might lead to smaller executables because arguments need not\nbe removed from the stack after such a function call.\n\nThis  option  can  lead  to reduced code size for functions that perform several calls to\nfunctions that get their arguments on the stack like calls to printf-like functions.\n"
                },
                {
                    "name": "-mbranch-cost=_",
                    "content": "Set the branch costs for conditional branch instructions to cost.  Reasonable values  for\ncost are small, non-negative integers. The default branch cost is 0.\n"
                },
                {
                    "name": "-mcall-prologues",
                    "content": "Functions  prologues/epilogues  are  expanded  as calls to appropriate subroutines.  Code\nsize is smaller.\n"
                },
                {
                    "name": "-mdouble=_",
                    "content": ""
                },
                {
                    "name": "-mlong-double=_",
                    "content": "Set the size (in bits) of the \"double\" or \"long  double\"  type,  respectively.   Possible\nvalues  for  bits  are  32  and  64.  Whether or not a specific value for bits is allowed\ndepends   on   the   \"--with-double=\"   and    \"--with-long-double=\"    configure options\n(\"https://gcc.gnu.org/install/configure.html#avr\"),  and the same applies for the default\nvalues of the options.\n"
                },
                {
                    "name": "-mgas-isr-prologues",
                    "content": "Interrupt service routines (ISRs) may use the \"gccisr\" pseudo instruction supported by\nGNU Binutils.  If this option is on, the feature can still  be  disabled  for  individual\nISRs  by  means  of  the  AVR  Function Attributes,,\"nogccisr\" function attribute.  This\nfeature is activated per default if optimization is on (but not with -Og, @pxref{Optimize\nOptions}), and if GNU Binutils support PR21683 (\"https://sourceware.org/PR21683\").\n"
                },
                {
                    "name": "-mint8",
                    "content": "Assume \"int\" to be 8-bit integer.  This affects the sizes of all types:  a  \"char\"  is  1\nbyte,  an  \"int\" is 1 byte, a \"long\" is 2 bytes, and \"long long\" is 4 bytes.  Please note\nthat this option does not conform to the C standards, but  it  results  in  smaller  code\nsize.\n"
                },
                {
                    "name": "-mmain-is-OS_task",
                    "content": "Do  not  save  registers  in \"main\".  The effect is the same like attaching attribute AVR\nFunction Attributes,,\"OStask\" to \"main\". It is activated per default if optimization  is\non.\n"
                },
                {
                    "name": "-mno-interrupts",
                    "content": "Generated code is not compatible with hardware interrupts.  Code size is smaller.\n"
                },
                {
                    "name": "-mrelax",
                    "content": "Try  to  replace  \"CALL\"  resp.  \"JMP\"  instruction  by  the shorter \"RCALL\" resp. \"RJMP\"\ninstruction if applicable.  Setting -mrelax just adds the  --mlink-relax  option  to  the\nassembler's command line and the --relax option to the linker's command line.\n\nJump  relaxing  is performed by the linker because jump offsets are not known before code\nis located. Therefore, the assembler code generated by the compiler is the same, but  the\ninstructions in the executable may differ from instructions in the assembler code.\n\nRelaxing  must  be  turned  on  if linker stubs are needed, see the section on \"EIND\" and\nlinker stubs below.\n"
                },
                {
                    "name": "-mstrict-X",
                    "content": "Use address register \"X\" in a way proposed by the hardware.  This means that \"X\" is  only\nused in indirect, post-increment or pre-decrement addressing.\n\nWithout  this  option,  the  \"X\" register may be used in the same way as \"Y\" or \"Z\" which\nthen is emulated by additional instructions.  For example, loading a value with \"X+const\"\naddressing with a small non-negative \"const < 64\" to a register Rn is performed as\n\nadiw r26, const   ; X += const\nld   <Rn>, X        ; <Rn> = *X\nsbiw r26, const   ; X -= const\n"
                },
                {
                    "name": "-mtiny-stack",
                    "content": "Only change the lower 8 bits of the stack pointer.\n"
                },
                {
                    "name": "-mfract-convert-truncate",
                    "content": "Allow to use truncation instead of  rounding  towards  zero  for  fractional  fixed-point\ntypes.\n"
                },
                {
                    "name": "-nodevicelib",
                    "content": "Don't link against AVR-LibC's device specific library \"lib<mcu>.a\".\n"
                },
                {
                    "name": "-nodevicespecs",
                    "content": "Don't  add -specs=device-specs/specs-mcu to the compiler driver's command line.  The user\ntakes responsibility for supplying the sub-processes like compiler proper, assembler  and\nlinker with appropriate command line options.  This means that the user has to supply her\nprivate  device  specs file by means of -specs=path-to-specs-file.  There is no more need\nfor option -mmcu=mcu.\n\nThis option can also serve as a replacement  for  the  older  way  of  specifying  custom\ndevice-specs  files  that  needed  -B  some-path to point to a directory which contains a\nfolder named \"device-specs\" which contains a specs file named \"specs-mcu\", where mcu  was\nspecified by -mmcu=mcu.\n"
                },
                {
                    "name": "-Waddr-space-convert",
                    "content": "Warn  about  conversions  between  address spaces in the case where the resulting address\nspace is not contained in the incoming address space.\n"
                },
                {
                    "name": "-Wmisspelled-isr",
                    "content": "Warn if the ISR is misspelled, i.e. without vector prefix.  Enabled by default.\n\n\"EIND\" and Devices with More Than 128 Ki Bytes of Flash\n\nPointers in the implementation are 16 bits wide.  The address  of  a  function  or  label  is\nrepresented  as  word address so that indirect jumps and calls can target any code address in\nthe range of 64 Ki words.\n\nIn order to facilitate indirect jump on devices with more than 128 Ki bytes of program memory\nspace, there is a special function register called \"EIND\" that  serves  as  most  significant\npart of the target address when \"EICALL\" or \"EIJMP\" instructions are used.\n\nIndirect  jumps  and  calls  on  these devices are handled as follows by the compiler and are\nsubject to some limitations:\n\n*   The compiler never sets \"EIND\".\n\n*   The compiler uses \"EIND\" implicitly in \"EICALL\"/\"EIJMP\" instructions or might read \"EIND\"\ndirectly in order to emulate an indirect call/jump by means of a \"RET\" instruction.\n\n*   The compiler assumes that \"EIND\" never changes during the  startup  code  or  during  the\napplication. In particular, \"EIND\" is not saved/restored in function or interrupt service\nroutine prologue/epilogue.\n\n*   For  indirect calls to functions and computed goto, the linker generates stubs. Stubs are\njump pads sometimes also called trampolines. Thus, the indirect call/jump jumps to such a\nstub.  The stub contains a direct jump to the desired address.\n\n*   Linker relaxation must be turned on so that the linker generates the stubs  correctly  in\nall situations. See the compiler option -mrelax and the linker option --relax.  There are\ncorner cases where the linker is supposed to generate stubs but aborts without relaxation\nand without a helpful error message.\n\n*   The  default  linker script is arranged for code with \"EIND = 0\".  If code is supposed to\nwork for a setup with \"EIND != 0\", a custom linker script has to  be  used  in  order  to\nplace  the  sections  whose  name start with \".trampolines\" into the segment where \"EIND\"\npoints to.\n\n*   The startup code from libgcc never sets \"EIND\".  Notice that startup code is a  blend  of\ncode  from  libgcc  and  AVR-LibC.   For  the  impact of AVR-LibC on \"EIND\", see the AVR-\nLibC user manual (\"https://www.nongnu.org/avr-libc/user-manual/\").\n\n*   It is legitimate for user-specific startup code to set up \"EIND\" early,  for  example  by\nmeans of initialization code located in section \".init3\". Such code runs prior to general\nstartup  code  that  initializes RAM and calls constructors, but after the bit of startup\ncode from AVR-LibC that sets \"EIND\" to the segment where the vector table is located.\n\n#include <avr/io.h>\n\nstatic void\nattribute((section(\".init3\"),naked,used,noinstrumentfunction))\ninit3seteind (void)\n{\nasm volatile (\"ldi r24,pmhh8(trampolinesstart)\\n\\t\"\n\"out %i0,r24\" :: \"n\" (&EIND) : \"r24\",\"memory\");\n}\n\nThe \"trampolinesstart\" symbol is defined in the linker script.\n\n*   Stubs are generated automatically by the linker if the following two conditions are met:\n\n-<The address of a label is taken by means of the \"gs\" modifier>\n(short for generate stubs) like so:\n\nLDI r24, lo8(gs(<func>))\nLDI r25, hi8(gs(<func>))\n\n-<The final location of that label is in a code segment>\noutside the segment where the stubs are located.\n\n*   The compiler emits such \"gs\" modifiers for code labels in the following situations:\n\n-<Taking address of a function or code label.>\n-<Computed goto.>\n-<If prologue-save function is used, see -mcall-prologues>\ncommand-line option.\n\n-<Switch/case dispatch tables. If you do not want such dispatch>\ntables you can specify the -fno-jump-tables command-line option.\n\n-<C and C++ constructors/destructors called during startup/shutdown.>\n-<If the tools hit a gs() modifier explained above.>\n*   Jumping to non-symbolic addresses like so is not supported:\n\nint main (void)\n{\n/* Call function at word address 0x2 */\nreturn ((int(*)(void)) 0x2)();\n}\n\nInstead, a stub has to be set up, i.e. the function has to be  called  through  a  symbol\n(\"func4\" in the example):\n\nint main (void)\n{\nextern int func4 (void);\n\n/* Call function at byte address 0x4 */\nreturn func4();\n}\n\nand  the application be linked with -Wl,--defsym,func4=0x4.  Alternatively, \"func4\" can\nbe defined in the linker script.\n\nHandling of the \"RAMPD\", \"RAMPX\", \"RAMPY\" and \"RAMPZ\" Special Function Registers\n\nSome AVR devices support memories larger than the 64 KiB range  that  can  be  accessed  with\n16-bit  pointers.   To  access  memory  locations outside this 64 KiB range, the content of a\n\"RAMP\" register is used as high part of the address: The \"X\", \"Y\", \"Z\"  address  register  is\nconcatenated  with  the \"RAMPX\", \"RAMPY\", \"RAMPZ\" special function register, respectively, to\nget a wide address. Similarly, \"RAMPD\" is used together with direct addressing.\n\n*   The startup code initializes the \"RAMP\" special function registers with zero.\n\n*   If a AVR Named Address Spaces,named address space other  than  generic  or  \"flash\"  is\nused, then \"RAMPZ\" is set as needed before the operation.\n\n*   If the device supports RAM larger than 64 KiB and the compiler needs to change \"RAMPZ\" to\naccomplish an operation, \"RAMPZ\" is reset to zero after the operation.\n\n*   If  the  device  comes  with  a  specific  \"RAMP\"  register,  the  ISR  prologue/epilogue\nsaves/restores that SFR and  initializes  it  with  zero  in  case  the  ISR  code  might\n(implicitly) use it.\n\n*   RAM  larger  than  64  KiB  is  not  supported by GCC for AVR targets.  If you use inline\nassembler to read from locations outside the 16-bit address range and change one  of  the\n\"RAMP\" registers, you must reset it to zero after the access.\n\nAVR Built-in Macros\n\nGCC  defines  several  built-in  macros  so  that  the user code can test for the presence or\nabsence of features.  Almost any of the following built-in macros  are  deduced  from  device\ncapabilities and thus triggered by the -mmcu= command-line option.\n\nFor  even  more  AVR-specific  built-in  macros see AVR Named Address Spaces and AVR Built-in\nFunctions.\n\n\"AVRARCH\"\nBuild-in macro that resolves to a decimal number that  identifies  the  architecture  and\ndepends on the -mmcu=mcu option.  Possible values are:\n\n2, 25, 3, 31, 35, 4, 5, 51, 6\n\nfor mcu=\"avr2\", \"avr25\", \"avr3\", \"avr31\", \"avr35\", \"avr4\", \"avr5\", \"avr51\", \"avr6\",\n\nrespectively and\n\n100, 102, 103, 104, 105, 106, 107\n\nfor  mcu=\"avrtiny\",  \"avrxmega2\",  \"avrxmega3\",  \"avrxmega4\",  \"avrxmega5\",  \"avrxmega6\",\n\"avrxmega7\", respectively.  If mcu  specifies  a  device,  this  built-in  macro  is  set\naccordingly. For example, with -mmcu=atmega8 the macro is defined to 4.\n\n\"AVRDevice\"\nSetting  -mmcu=device  defines  this built-in macro which reflects the device's name. For\nexample, -mmcu=atmega8 defines the  built-in  macro  \"AVRATmega8\",  -mmcu=attiny261a\ndefines \"AVRATtiny261A\", etc.\n\nThe  built-in macros' names follow the scheme \"AVRDevice\" where Device is the device\nname as from the AVR user manual. The difference between Device in the built-in macro and\ndevice in -mmcu=device is that the latter is always lowercase.\n\nIf device is not a device but only a core architecture like  avr51,  this  macro  is  not\ndefined.\n\n\"AVRDEVICENAME\"\nSetting  -mmcu=device defines this built-in macro to the device's name. For example, with\n-mmcu=atmega8 the macro is defined to \"atmega8\".\n\nIf device is not a device but only a core architecture like  avr51,  this  macro  is  not\ndefined.\n\n\"AVRXMEGA\"\nThe device / architecture belongs to the XMEGA family of devices.\n\n\"AVRHAVEADIW\"\nThe device has the \"ADIW\" and \"SBIW\" instructions.\n\n\"AVRHAVEELPM\"\nThe device has the \"ELPM\" instruction.\n\n\"AVRHAVEELPMX\"\nThe device has the \"ELPM Rn,Z\" and \"ELPM Rn,Z+\" instructions.\n\n\"AVRHAVELPMX\"\nThe device has the \"LPM Rn,Z\" and \"LPM Rn,Z+\" instructions.\n\n\"AVRHAVEMOVW\"\nThe device has the \"MOVW\" instruction to perform 16-bit register-register moves.\n\n\"AVRHAVEMUL\"\nThe device has a hardware multiplier.\n\n\"AVRHAVEJMPCALL\"\nThe device has the \"JMP\" and \"CALL\" instructions.  This is the case for devices with more\nthan 8 KiB of program memory.\n\n\"AVRHAVEEIJMPEICALL\"\n\"AVR3BYTEPC\"\nThe  device has the \"EIJMP\" and \"EICALL\" instructions.  This is the case for devices with\nmore than 128 KiB of program memory.  This also means that the program counter (PC) is  3\nbytes wide.\n\n\"AVR2BYTEPC\"\nThe program counter (PC) is 2 bytes wide. This is the case for devices with up to 128 KiB\nof program memory.\n\n\"AVRHAVE8BITSP\"\n\"AVRHAVE16BITSP\"\nThe  stack  pointer (SP) register is treated as 8-bit respectively 16-bit register by the\ncompiler.  The definition of these macros is affected by -mtiny-stack.\n\n\"AVRHAVESPH\"\n\"AVRSP8\"\nThe device has the SPH (high part of stack pointer) special function register or  has  an\n8-bit  stack pointer, respectively.  The definition of these macros is affected by -mmcu=\nand in the cases of -mmcu=avr2 and -mmcu=avr25 also by -msp8.\n\n\"AVRHAVERAMPD\"\n\"AVRHAVERAMPX\"\n\"AVRHAVERAMPY\"\n\"AVRHAVERAMPZ\"\nThe device  has  the  \"RAMPD\",  \"RAMPX\",  \"RAMPY\",  \"RAMPZ\"  special  function  register,\nrespectively.\n\n\"NOINTERRUPTS\"\nThis macro reflects the -mno-interrupts command-line option.\n\n\"AVRERRATASKIP\"\n\"AVRERRATASKIPJMPCALL\"\nSome  AVR  devices  (AT90S8515, ATmega103) must not skip 32-bit instructions because of a\nhardware erratum.  Skip instructions are \"SBRS\", \"SBRC\", \"SBIS\", \"SBIC\" and \"CPSE\".   The\nsecond macro is only defined if \"AVRHAVEJMPCALL\" is also set.\n\n\"AVRISARMW\"\nThe device has Read-Modify-Write instructions (XCH, LAC, LAS and LAT).\n\n\"AVRSFROFFSET=offset\"\nInstructions  that  can address I/O special function registers directly like \"IN\", \"OUT\",\n\"SBI\", etc. may use a different address as if addressed by an instruction to  access  RAM\nlike  \"LD\"  or  \"STS\".  This  offset  depends  on  the  device architecture and has to be\nsubtracted from the RAM address in order to get the respective I/O address.\n\n\"AVRSHORTCALLS\"\nThe -mshort-calls command line option is set.\n\n\"AVRPMBASEADDRESS=addr\"\nSome devices support reading from flash memory by means of \"LD*\" instructions.  The flash\nmemory is seen in the data address space at an offset of  \"AVRPMBASEADDRESS\".   If\nthis  macro is not defined, this feature is not available.  If defined, the address space\nis linear and there is no need to put \".rodata\" into RAM.  This is handled by the default\nlinker description file, and is currently available for \"avrtiny\" and \"avrxmega3\".   Even\nmore  convenient,  there is no need to use address spaces like \"flash\" or features like\nattribute \"progmem\" and \"pgmread*\".\n\n\"WITHAVRLIBC\"\nThe compiler is configured to be used together with  AVR-Libc.   See  the  --with-avrlibc\nconfigure option.\n\n\"HAVEDOUBLEMULTILIB\"\nDefined if -mdouble= acts as a multilib option.\n\n\"HAVEDOUBLE32\"\n\"HAVEDOUBLE64\"\nDefined if the compiler supports 32-bit double resp. 64-bit double.  The actual layout is\nspecified by option -mdouble=.\n\n\"DEFAULTDOUBLE\"\nThe  size in bits of \"double\" if -mdouble= is not set.  To test the layout of \"double\" in\na program, use the built-in macro \"SIZEOFDOUBLE\".\n\n\"HAVELONGDOUBLE32\"\n\"HAVELONGDOUBLE64\"\n\"HAVELONGDOUBLEMULTILIB\"\n\"DEFAULTLONGDOUBLE\"\nSame as above, but for \"long double\" instead of \"double\".\n\n\"WITHDOUBLECOMPARISON\"\nReflects    the     \"--with-double-comparison={tristate|bool|libf7}\"     configure option\n(\"https://gcc.gnu.org/install/configure.html#avr\") and is defined to 2 or 3.\n\n\"WITHLIBF7LIBGCC\"\n\"WITHLIBF7MATH\"\n\"WITHLIBF7MATHSYMBOLS\"\nReflects       the       \"--with-libf7={libgcc|math|math-symbols}\"       configure option\n(\"https://gcc.gnu.org/install/configure.html#avr\").\n\nAVR Internal Options\n\nThe following options are used internally by the compiler and to communicate  between  device\nspecs  files  and  the  compiler  proper.  You  don't  need  to set these options by hand, in\nparticular they are not optimization options.  Using these options in the wrong way may  lead\nto  sub-optimal  or  wrong code.  They are documented for completeness, and in order to get a\nbetter understanding of device specs (\"https://gcc.gnu.org/wiki/avr-gcc#spec-files\") files.\n"
                },
                {
                    "name": "-mn-flash=_",
                    "content": "Assume that the flash memory has a size of num  times  64  KiB.   This  determines  which\n\"flashN\" address spaces are available.\n"
                },
                {
                    "name": "-mrmw",
                    "content": "Assume  that  the  device supports the Read-Modify-Write instructions \"XCH\", \"LAC\", \"LAS\"\nand \"LAT\".\n"
                },
                {
                    "name": "-mshort-calls",
                    "content": "Assume that \"RJMP\" and \"RCALL\" can target the whole program memory. This option  is  used\nfor multilib generation and selection for the devices from architecture \"avrxmega3\".\n"
                },
                {
                    "name": "-mskip-bug",
                    "content": "Generate  code  without  skips  (\"CPSE\",  \"SBRS\",  \"SBRC\",  \"SBIS\",  \"SBIC\")  over 32-bit\ninstructions.\n"
                },
                {
                    "name": "-msp8",
                    "content": "Treat the stack pointer register as an 8-bit register, i.e. assume the high byte  of  the\nstack pointer is zero.  This option is used by the compiler to select and build multilibs\nfor  architectures  \"avr2\" and \"avr25\".  These architectures mix devices with and without\n\"SPH\".\n\nBlackfin Options\n"
                },
                {
                    "name": "-mcpu=_ -_",
                    "content": "Specifies the name of the target Blackfin processor.  Currently, cpu can be one of bf512,\nbf514, bf516, bf518, bf522, bf523, bf524,  bf525,  bf526,  bf527,  bf531,  bf532,  bf533,\nbf534,  bf536,  bf537,  bf538,  bf539, bf542, bf544, bf547, bf548, bf549, bf542m, bf544m,\nbf547m, bf548m, bf549m, bf561, bf592.\n\nThe optional sirevision specifies the silicon revision of the target Blackfin  processor.\nAny  workarounds  available for the targeted silicon revision are enabled.  If sirevision\nis none, no workarounds are enabled.  If sirevision  is  any,  all  workarounds  for  the\ntargeted  processor  are  enabled.   The  \"SILICONREVISION\"  macro is defined to two\nhexadecimal digits representing the major and minor numbers in the silicon revision.   If\nsirevision is none, the \"SILICONREVISION\" is not defined.  If sirevision is any, the\n\"SILICONREVISION\" is defined to be 0xffff.  If this optional sirevision is not used,\nGCC assumes the latest known silicon revision of the targeted Blackfin processor.\n\nGCC defines a preprocessor macro for the specified cpu.  For the bfin-elf toolchain, this\noption  causes  the  hardware  BSP  provided  by libgloss to be linked in if -msim is not\ngiven.\n\nWithout this option, bf532 is used as the processor by default.\n\nNote that support for bf561 is incomplete.  For bf561, only  the  preprocessor  macro  is\ndefined.\n"
                },
                {
                    "name": "-msim",
                    "content": "Specifies  that  the program will be run on the simulator.  This causes the simulator BSP\nprovided by libgloss to  be  linked  in.   This  option  has  effect  only  for  bfin-elf\ntoolchain.  Certain other options, such as -mid-shared-library and -mfdpic, imply -msim.\n"
                },
                {
                    "name": "-momit-leaf-frame-pointer",
                    "content": "Don't  keep  the  frame  pointer  in  a  register  for  leaf  functions.  This avoids the\ninstructions to save, set up and restore frame  pointers  and  makes  an  extra  register\navailable in leaf functions.\n"
                },
                {
                    "name": "-mspecld-anomaly",
                    "content": "When  enabled,  the compiler ensures that the generated code does not contain speculative\nloads after jump instructions. If this option is  used,  \"WORKAROUNDSPECULATIVELOADS\"\nis defined.\n"
                },
                {
                    "name": "-mno-specld-anomaly",
                    "content": "Don't generate extra code to prevent speculative loads from occurring.\n"
                },
                {
                    "name": "-mcsync-anomaly",
                    "content": "When  enabled,  the  compiler  ensures  that the generated code does not contain CSYNC or\nSSYNC instructions too  soon  after  conditional  branches.   If  this  option  is  used,\n\"WORKAROUNDSPECULATIVESYNCS\" is defined.\n"
                },
                {
                    "name": "-mno-csync-anomaly",
                    "content": "Don't  generate extra code to prevent CSYNC or SSYNC instructions from occurring too soon\nafter a conditional branch.\n"
                },
                {
                    "name": "-mlow64k",
                    "content": "When enabled, the compiler is free to take advantage of the  knowledge  that  the  entire\nprogram fits into the low 64k of memory.\n"
                },
                {
                    "name": "-mno-low64k",
                    "content": "Assume that the program is arbitrarily large.  This is the default.\n"
                },
                {
                    "name": "-mstack-check-l1",
                    "content": "Do  stack  checking  using  information  placed  into L1 scratchpad memory by the uClinux\nkernel.\n"
                },
                {
                    "name": "-mid-shared-library",
                    "content": "Generate code that supports shared libraries via the library ID method.  This allows  for\nexecute  in  place  and  shared  libraries  in  an  environment  without  virtual  memory\nmanagement.  This option implies -fPIC.  With a  bfin-elf  target,  this  option  implies\n-msim.\n"
                },
                {
                    "name": "-mno-id-shared-library",
                    "content": "Generate  code that doesn't assume ID-based shared libraries are being used.  This is the\ndefault.\n"
                },
                {
                    "name": "-mleaf-id-shared-library",
                    "content": "Generate code that supports shared libraries via the library ID method, but assumes  that\nthis library or executable won't link against any other ID shared libraries.  That allows\nthe compiler to use faster code for jumps and calls.\n"
                },
                {
                    "name": "-mno-leaf-id-shared-library",
                    "content": "Do  not  assume  that the code being compiled won't link against any ID shared libraries.\nSlower code is generated for jump and call insns.\n"
                },
                {
                    "name": "-mshared-library-id=n",
                    "content": "Specifies the identification number  of  the  ID-based  shared  library  being  compiled.\nSpecifying  a  value of 0 generates more compact code; specifying other values forces the\nallocation of that number to the current library but is no more space- or  time-efficient\nthan omitting this option.\n"
                },
                {
                    "name": "-msep-data",
                    "content": "Generate  code  that  allows the data segment to be located in a different area of memory\nfrom the text segment.  This allows for  execute  in  place  in  an  environment  without\nvirtual memory management by eliminating relocations against the text section.\n"
                },
                {
                    "name": "-mno-sep-data",
                    "content": "Generate  code  that assumes that the data segment follows the text segment.  This is the\ndefault.\n"
                },
                {
                    "name": "-mlong-calls",
                    "content": ""
                },
                {
                    "name": "-mno-long-calls",
                    "content": "Tells the compiler to perform function calls by first loading the address of the function\ninto a register and then performing a subroutine call on this register.  This  switch  is\nneeded  if the target function lies outside of the 24-bit addressing range of the offset-\nbased version of subroutine call instruction.\n\nThis feature is not enabled by default.  Specifying -mno-long-calls restores the  default\nbehavior.   Note  these  switches  have  no  effect on how the compiler generates code to\nhandle function calls via function pointers.\n"
                },
                {
                    "name": "-mfast-fp",
                    "content": "Link with the fast  floating-point  library.  This  library  relaxes  some  of  the  IEEE\nfloating-point  standard's  rules  for checking inputs against Not-a-Number (NAN), in the\ninterest of performance.\n"
                },
                {
                    "name": "-minline-plt",
                    "content": "Enable inlining of PLT entries in function calls to functions that are not known to  bind\nlocally.  It has no effect without -mfdpic.\n"
                },
                {
                    "name": "-mmulticore",
                    "content": "Build  a  standalone  application  for multicore Blackfin processors.  This option causes\nproper start files and link scripts supporting multicore to  be  used,  and  defines  the\nmacro \"BFINMULTICORE\".  It can only be used with -mcpu=bf561[-sirevision].\n\nThis  option  can be used with -mcorea or -mcoreb, which selects the one-application-per-\ncore programming model.  Without -mcorea  or  -mcoreb,  the  single-application/dual-core\nprogramming  model is used. In this model, the main function of Core B should be named as\n\"corebmain\".\n\nIf this option is not used, the single-core application programming model is used.\n"
                },
                {
                    "name": "-mcorea",
                    "content": "Build a standalone application for Core A of BF561 when  using  the  one-application-per-\ncore  programming  model. Proper start files and link scripts are used to support Core A,\nand the macro \"BFINCOREA\" is defined.  This option can only  be  used  in  conjunction\nwith -mmulticore.\n"
                },
                {
                    "name": "-mcoreb",
                    "content": "Build  a  standalone  application for Core B of BF561 when using the one-application-per-\ncore programming model. Proper start files and link scripts are used to support  Core  B,\nand the macro \"BFINCOREB\" is defined. When this option is used, \"corebmain\" should be\nused instead of \"main\".  This option can only be used in conjunction with -mmulticore.\n"
                },
                {
                    "name": "-msdram",
                    "content": "Build a standalone application for SDRAM. Proper start files and link scripts are used to\nput  the  application  into  SDRAM,  and the macro \"BFINSDRAM\" is defined.  The loader\nshould initialize SDRAM before loading the application.\n"
                },
                {
                    "name": "-micplb",
                    "content": "Assume that ICPLBs are enabled at run time.   This  has  an  effect  on  certain  anomaly\nworkarounds.   For  Linux  targets,  the  default  is  to  assume ICPLBs are enabled; for\nstandalone applications the default is off.\n\nC6X Options\n"
                },
                {
                    "name": "-march=_",
                    "content": "This specifies the name of the target architecture.  GCC uses this name to determine what\nkind of instructions it can emit when generating assembly code.  Permissible  names  are:\nc62x, c64x, c64x+, c67x, c67x+, c674x.\n"
                },
                {
                    "name": "-mbig-endian",
                    "content": "Generate code for a big-endian target.\n"
                },
                {
                    "name": "-mlittle-endian",
                    "content": "Generate code for a little-endian target.  This is the default.\n"
                },
                {
                    "name": "-msim",
                    "content": "Choose startup files and linker script suitable for the simulator.\n"
                },
                {
                    "name": "-msdata=default",
                    "content": "Put  small  global  and  static  data  in the \".neardata\" section, which is pointed to by\nregister \"B14\".  Put small uninitialized global and static data in  the  \".bss\"  section,\nwhich  is  adjacent  to  the  \".neardata\"  section.   Put  small  read-only data into the\n\".rodata\" section.  The  corresponding  sections  used  for  large  pieces  of  data  are\n\".fardata\", \".far\" and \".const\".\n"
                },
                {
                    "name": "-msdata=all",
                    "content": "Put  all data, not just small objects, into the sections reserved for small data, and use\naddressing relative to the \"B14\" register to access them.\n"
                },
                {
                    "name": "-msdata=none",
                    "content": "Make no use of the sections reserved for small data, and use absolute addresses to access\nall data.  Put all initialized global and static data in the \".fardata\" section, and  all\nuninitialized  data  in  the  \".far\"  section.   Put  all constant data into the \".const\"\nsection.\n\nCRIS Options\n\nThese options are defined specifically for the CRIS ports.\n"
                },
                {
                    "name": "-march=_",
                    "content": ""
                },
                {
                    "name": "-mcpu=_",
                    "content": "Generate code for the specified architecture.  The choices for architecture-type are  v3,\nv8 and v10 for respectively ETRAX 4, ETRAX 100, and ETRAX 100 LX.  Default is v0.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "Tune  to architecture-type everything applicable about the generated code, except for the\nABI and the set of available instructions.  The choices  for  architecture-type  are  the\nsame as for -march=architecture-type.\n"
                },
                {
                    "name": "-mmax-stack-frame=_",
                    "content": "Warn when the stack frame of a function exceeds n bytes.\n"
                },
                {
                    "name": "-metrax4",
                    "content": ""
                },
                {
                    "name": "-metrax100",
                    "content": "The   options   -metrax4   and  -metrax100  are  synonyms  for  -march=v3  and  -march=v8\nrespectively.\n"
                },
                {
                    "name": "-mmul-bug-workaround",
                    "content": ""
                },
                {
                    "name": "-mno-mul-bug-workaround",
                    "content": "Work around a bug in the \"muls\" and \"mulu\" instructions for CPU models where it  applies.\nThis option is disabled by default.\n"
                },
                {
                    "name": "-mpdebug",
                    "content": "Enable CRIS-specific verbose debug-related information in the assembly code.  This option\nalso  has the effect of turning off the #NOAPP formatted-code indicator to the assembler\nat the beginning of the assembly file.\n"
                },
                {
                    "name": "-mcc-init",
                    "content": "Do not use condition-code results from previous instruction; always emit compare and test\ninstructions before use of condition codes.\n"
                },
                {
                    "name": "-mno-side-effects",
                    "content": "Do not emit instructions with side effects in addressing modes other than post-increment.\n"
                },
                {
                    "name": "-mstack-align",
                    "content": ""
                },
                {
                    "name": "-mno-stack-align",
                    "content": ""
                },
                {
                    "name": "-mdata-align",
                    "content": ""
                },
                {
                    "name": "-mno-data-align",
                    "content": ""
                },
                {
                    "name": "-mconst-align",
                    "content": ""
                },
                {
                    "name": "-mno-const-align",
                    "content": "These options (no-  options)  arrange  (eliminate  arrangements)  for  the  stack  frame,\nindividual  data  and constants to be aligned for the maximum single data access size for\nthe chosen CPU model.  The default is to arrange for 32-bit alignment.  ABI details  such\nas structure layout are not affected by these options.\n"
                },
                {
                    "name": "-m32-bit",
                    "content": ""
                },
                {
                    "name": "-m16-bit",
                    "content": ""
                },
                {
                    "name": "-m8-bit",
                    "content": "Similar  to  the  stack-  data-  and const-align options above, these options arrange for\nstack frame, writable data and constants to all be 32-bit, 16-bit or 8-bit aligned.   The\ndefault is 32-bit alignment.\n"
                },
                {
                    "name": "-mno-prologue-epilogue",
                    "content": ""
                },
                {
                    "name": "-mprologue-epilogue",
                    "content": "With  -mno-prologue-epilogue,  the normal function prologue and epilogue which set up the\nstack frame are omitted and no return instructions or return sequences are  generated  in\nthe  code.  Use this option only together with visual inspection of the compiled code: no\nwarnings or errors are generated when call-saved registers must be saved, or storage  for\nlocal variables needs to be allocated.\n"
                },
                {
                    "name": "-melf",
                    "content": "Legacy no-op option.\n"
                },
                {
                    "name": "-sim",
                    "content": "This option arranges to link with input-output functions from a simulator library.  Code,\ninitialized data and zero-initialized data are allocated consecutively.\n"
                },
                {
                    "name": "-sim2",
                    "content": "Like  -sim,  but  pass  linker options to locate initialized data at 0x40000000 and zero-\ninitialized data at 0x80000000.\n\nC-SKY Options\n\nGCC supports these options when compiling for C-SKY V2 processors.\n"
                },
                {
                    "name": "-march=_",
                    "content": "Specify the C-SKY target architecture.  Valid values for arch are: ck801,  ck802,  ck803,\nck807, and ck810.  The default is ck810.\n"
                },
                {
                    "name": "-mcpu=_",
                    "content": "Specify  the  C-SKY  target  processor.   Valid values for cpu are: ck801, ck801t, ck802,\nck802t, ck802j,  ck803,  ck803h,  ck803t,  ck803ht,  ck803f,  ck803fh,  ck803e,  ck803eh,\nck803et,  ck803eht,  ck803ef,  ck803efh, ck803ft, ck803eft, ck803efht, ck803r1, ck803hr1,\nck803tr1, ck803htr1, ck803fr1, ck803fhr1,  ck803er1,  ck803ehr1,  ck803etr1,  ck803ehtr1,\nck803efr1,  ck803efhr1,  ck803ftr1,  ck803eftr1,  ck803efhtr1,  ck803s, ck803st, ck803se,\nck803sf, ck803sef, ck803seft, ck807e, ck807ef, ck807, ck807f, ck810e,  ck810et,  ck810ef,\nck810eft, ck810, ck810v, ck810f, ck810t, ck810fv, ck810tv, ck810ft, and ck810ftv.\n"
                },
                {
                    "name": "-mbig-endian",
                    "content": ""
                },
                {
                    "name": "-EB",
                    "content": ""
                },
                {
                    "name": "-mlittle-endian",
                    "content": ""
                },
                {
                    "name": "-EL",
                    "content": ""
                },
                {
                    "name": "-mfloat-abi=_",
                    "content": "Specifies  which  floating-point  ABI  to  use.  Permissible values are: soft, softfp and\nhard.\n\nSpecifying soft causes GCC to generate output containing library calls for floating-point\noperations.   softfp  allows  the  generation  of  code  using  hardware   floating-point\ninstructions,  but still uses the soft-float calling conventions.  hard allows generation\nof floating-point instructions and uses FPU-specific calling conventions.\n\nThe default depends on the specific target configuration.  Note that the  hard-float  and\nsoft-float  ABIs  are  not link-compatible; you must compile your entire program with the\nsame ABI, and link with a compatible set of libraries.\n"
                },
                {
                    "name": "-mhard-float",
                    "content": ""
                },
                {
                    "name": "-msoft-float",
                    "content": "Select hardware or software floating-point implementations.  The default is soft float.\n"
                },
                {
                    "name": "-mdouble-float",
                    "content": ""
                },
                {
                    "name": "-mno-double-float",
                    "content": "When -mhard-float is in effect, enable generation of double-precision float instructions.\nThis is the default except when compiling for CK803.\n"
                },
                {
                    "name": "-mfdivdu",
                    "content": ""
                },
                {
                    "name": "-mno-fdivdu",
                    "content": "When -mhard-float is in effect, enable generation of  \"frecipd\",  \"fsqrtd\",  and  \"fdivd\"\ninstructions.  This is the default except when compiling for CK803.\n"
                },
                {
                    "name": "-mfpu=_",
                    "content": "Select  the  floating-point  processor.   This option can only be used with -mhard-float.\nValues  for  fpu  are  fpv2sf  (equivalent  to  -mno-double-float   -mno-fdivdu),   fpv2\n(-mdouble-float -mno-divdu), and fpv2divd (-mdouble-float -mdivdu).\n"
                },
                {
                    "name": "-melrw",
                    "content": ""
                },
                {
                    "name": "-mno-elrw",
                    "content": "Enable  the  extended  \"lrw\"  instruction.   This option defaults to on for CK801 and off\notherwise.\n"
                },
                {
                    "name": "-mistack",
                    "content": ""
                },
                {
                    "name": "-mno-istack",
                    "content": "Enable interrupt stack instructions; the default is off.\n\nThe -mistack option is required to handle the \"interrupt\" and \"isr\" function attributes.\n"
                },
                {
                    "name": "-mmp",
                    "content": "Enable multiprocessor instructions; the default is off.\n"
                },
                {
                    "name": "-mcp",
                    "content": "Enable coprocessor instructions; the default is off.\n"
                },
                {
                    "name": "-mcache",
                    "content": "Enable coprocessor instructions; the default is off.\n"
                },
                {
                    "name": "-msecurity",
                    "content": "Enable C-SKY security instructions; the default is off.\n"
                },
                {
                    "name": "-mtrust",
                    "content": "Enable C-SKY trust instructions; the default is off.\n"
                },
                {
                    "name": "-mdsp",
                    "content": ""
                },
                {
                    "name": "-medsp",
                    "content": ""
                },
                {
                    "name": "-mvdsp",
                    "content": "Enable C-SKY DSP, Enhanced DSP, or Vector DSP instructions, respectively.  All  of  these\noptions default to off.\n"
                },
                {
                    "name": "-mdiv",
                    "content": ""
                },
                {
                    "name": "-mno-div",
                    "content": "Generate divide instructions.  Default is off.\n"
                },
                {
                    "name": "-msmart",
                    "content": ""
                },
                {
                    "name": "-mno-smart",
                    "content": "Generate  code  for  Smart Mode, using only registers numbered 0-7 to allow use of 16-bit\ninstructions.  This option is ignored for CK801 where this is the required behavior,  and\nit defaults to on for CK802.  For other targets, the default is off.\n"
                },
                {
                    "name": "-mhigh-registers",
                    "content": ""
                },
                {
                    "name": "-mno-high-registers",
                    "content": "Generate  code  using the high registers numbered 16-31.  This option is not supported on\nCK801, CK802, or CK803, and is enabled by default for other processors.\n"
                },
                {
                    "name": "-manchor",
                    "content": ""
                },
                {
                    "name": "-mno-anchor",
                    "content": "Generate code using global anchor symbol addresses.\n"
                },
                {
                    "name": "-mpushpop",
                    "content": ""
                },
                {
                    "name": "-mno-pushpop",
                    "content": "Generate code using \"push\" and \"pop\" instructions.  This option defaults to on.\n"
                },
                {
                    "name": "-mmultiple-stld",
                    "content": ""
                },
                {
                    "name": "-mstm",
                    "content": ""
                },
                {
                    "name": "-mno-multiple-stld",
                    "content": ""
                },
                {
                    "name": "-mno-stm",
                    "content": "Generate code using \"stm\" and \"ldm\" instructions.  This option isn't supported  on  CK801\nbut is enabled by default on other processors.\n"
                },
                {
                    "name": "-mconstpool",
                    "content": ""
                },
                {
                    "name": "-mno-constpool",
                    "content": "Create  constant  pools  in  the compiler instead of deferring it to the assembler.  This\noption is the default and required for correct code generation on CK801 and CK802, and is\noptional on other processors.\n"
                },
                {
                    "name": "-mstack-size",
                    "content": ""
                },
                {
                    "name": "-mno-stack-size",
                    "content": "Emit \".stacksize\" directives for each function in  the  assembly  output.   This  option\ndefaults to off.\n"
                },
                {
                    "name": "-mccrt",
                    "content": ""
                },
                {
                    "name": "-mno-ccrt",
                    "content": "Generate  code for the C-SKY compiler runtime instead of libgcc.  This option defaults to\noff.\n"
                },
                {
                    "name": "-mbranch-cost=_",
                    "content": "Set the branch costs to roughly \"n\" instructions.  The default is 1.\n"
                },
                {
                    "name": "-msched-prolog",
                    "content": ""
                },
                {
                    "name": "-mno-sched-prolog",
                    "content": "Permit scheduling of function prologue and epilogue sequences.   Using  this  option  can\nresult in code that is not compliant with the C-SKY V2 ABI prologue requirements and that\ncannot be debugged or backtraced.  It is disabled by default.\n"
                },
                {
                    "name": "-msim",
                    "content": "Links  the  library  libsemi.a  which  is in compatible with simulator. Applicable to ELF\ncompiler only.\n\nDarwin Options\n\nThese options are defined for all architectures running the Darwin operating system.\n\nFSF GCC on Darwin does not create \"fat\" object files; it  creates  an  object  file  for  the\nsingle  architecture  that  GCC was built to target.  Apple's GCC on Darwin does create \"fat\"\nfiles if multiple -arch options are used; it does  so  by  running  the  compiler  or  linker\nmultiple times and joining the results together with lipo.\n\nThe  subtype  of the file created (like ppc7400 or ppc970 or i686) is determined by the flags\nthat specify the ISA that GCC is targeting, like -mcpu or -march.  The  -forcecpusubtypeALL\noption can be used to override this.\n\nThe  Darwin tools vary in their behavior when presented with an ISA mismatch.  The assembler,\nas, only permits instructions to be used that are valid for the subtype of  the  file  it  is\ngenerating,  so  you  cannot put 64-bit instructions in a ppc750 object file.  The linker for\nshared libraries, /usr/bin/libtool, fails and prints an error if asked  to  create  a  shared\nlibrary  with  a less restrictive subtype than its input files (for instance, trying to put a\nppc970 object file in a ppc7400 library).  The linker for executables, ld, quietly gives  the\nexecutable the most restrictive subtype of any of its input files.\n"
                },
                {
                    "name": "-F_",
                    "content": "Add the framework directory dir to the head of the list of directories to be searched for\nheader  files.   These directories are interleaved with those specified by -I options and\nare scanned in a left-to-right order.\n\nA framework directory is a directory with frameworks in it.  A framework is  a  directory\nwith  a  Headers  and/or  PrivateHeaders  directory contained directly in it that ends in\n.framework.  The name of a  framework  is  the  name  of  this  directory  excluding  the\n.framework.   Headers  associated  with  the  framework  are  found  in  one of those two\ndirectories, with Headers being searched first.  A subframework is a framework  directory\nthat is in a framework's Frameworks directory.  Includes of subframework headers can only\nappear  in  a  header  of  a  framework  that  contains the subframework, or in a sibling\nsubframework header.  Two subframeworks are siblings if they occur in the same framework.\nA subframework should not have the same name as a framework; a warning is issued if  this\nis  violated.   Currently  a  subframework  cannot have subframeworks; in the future, the\nmechanism may be extended to support this.  The  standard  frameworks  can  be  found  in\n/System/Library/Frameworks  and  /Library/Frameworks.   An  example  include  looks  like\n\"#include <Framework/header.h>\", where Framework denotes the name of  the  framework  and\nheader.h is found in the PrivateHeaders or Headers directory.\n"
                },
                {
                    "name": "-iframework_",
                    "content": "Like  -F  except  the  directory is a treated as a system directory.  The main difference\nbetween this -iframework and -F is that with -iframework the compiler does not warn about\nconstructs contained within header files found via dir.  This option is  valid  only  for\nthe C family of languages.\n"
                },
                {
                    "name": "-gused",
                    "content": "Emit  debugging  information for symbols that are used.  For stabs debugging format, this\nenables -feliminate-unused-debug-symbols.  This is by default ON.\n"
                },
                {
                    "name": "-gfull",
                    "content": "Emit debugging information for all symbols and types.\n"
                },
                {
                    "name": "-fconstant-cfstrings",
                    "content": "The -fconstant-cfstrings is an alias for -mconstant-cfstrings.\n"
                },
                {
                    "name": "-mconstant-cfstrings",
                    "content": "When the NeXT runtime is  being  used  (the  default  on  these  systems),  override  any\n-fconstant-string-class  setting  and cause \"@\"...\"\"  literals to be laid out as constant\nCoreFoundation strings.\n"
                },
                {
                    "name": "-mmacosx-version-min=_",
                    "content": "The earliest version of MacOS X that this executable will run  on  is  version.   Typical\nvalues supported for version include 12, 10.12, and 10.5.8.\n\nIf  the  compiler  was built to use the system's headers by default, then the default for\nthis option is the system version on which the compiler is running, otherwise the default\nis to make choices that are compatible with as many systems and code bases as possible.\n"
                },
                {
                    "name": "-mkernel",
                    "content": "Enable  kernel  development  mode.   The  -mkernel  option  sets  -static,   -fno-common,\n-fno-use-cxa-atexit,  -fno-exceptions,  -fno-non-call-exceptions, -fapple-kext, -fno-weak\nand  -fno-rtti  where  applicable.   This  mode  also  sets  -mno-altivec,  -msoft-float,\n-fno-builtin and -mlong-branch for PowerPC targets.\n"
                },
                {
                    "name": "-mone-byte-bool",
                    "content": "Override the defaults for \"bool\" so that \"sizeof(bool)==1\".  By default sizeof(bool) is 4\nwhen compiling for Darwin/PowerPC and 1 when compiling for Darwin/x86, so this option has\nno effect on x86.\n\nWarning:  The  -mone-byte-bool  switch  causes  GCC  to  generate code that is not binary\ncompatible with code generated without  that  switch.   Using  this  switch  may  require\nrecompiling  all other modules in a program, including system libraries.  Use this switch\nto conform to a non-default data model.\n"
                },
                {
                    "name": "-mfix-and-continue",
                    "content": ""
                },
                {
                    "name": "-ffix-and-continue",
                    "content": ""
                },
                {
                    "name": "-findirect-data",
                    "content": "Generate code suitable  for  fast  turnaround  development,  such  as  to  allow  GDB  to\ndynamically   load   .o   files   into  already-running  programs.   -findirect-data  and\n-ffix-and-continue are provided for backwards compatibility.\n"
                },
                {
                    "name": "-all_load",
                    "content": "Loads all members of static archive libraries.  See man ld(1) for more information.\n"
                },
                {
                    "name": "-arch_errors_fatal",
                    "content": "Cause the errors having to do with files that have the wrong architecture to be fatal.\n"
                },
                {
                    "name": "-bind_at_load",
                    "content": "Causes the output file to be marked such that the dynamic linker will bind all  undefined\nreferences when the file is loaded or launched.\n"
                },
                {
                    "name": "-bundle",
                    "content": "Produce a Mach-o bundle format file.  See man ld(1) for more information.\n"
                },
                {
                    "name": "-bundle_loader _",
                    "content": "This  option  specifies the executable that will load the build output file being linked.\nSee man ld(1) for more information.\n"
                },
                {
                    "name": "-dynamiclib",
                    "content": "When passed this option, GCC produces a dynamic library instead  of  an  executable  when\nlinking, using the Darwin libtool command.\n"
                },
                {
                    "name": "-force_cpusubtype_ALL",
                    "content": "This  causes  GCC's output file to have the ALL subtype, instead of one controlled by the\n-mcpu or -march option.\n"
                },
                {
                    "name": "-allowable_client  _",
                    "content": ""
                },
                {
                    "name": "-client_name",
                    "content": ""
                },
                {
                    "name": "-compatibility_version",
                    "content": ""
                },
                {
                    "name": "-current_version",
                    "content": ""
                },
                {
                    "name": "-dead_strip",
                    "content": ""
                },
                {
                    "name": "-dependency-file",
                    "content": ""
                },
                {
                    "name": "-dylib_file",
                    "content": ""
                },
                {
                    "name": "-dylinker_install_name",
                    "content": ""
                },
                {
                    "name": "-dynamic",
                    "content": ""
                },
                {
                    "name": "-exported_symbols_list",
                    "content": ""
                },
                {
                    "name": "-filelist",
                    "content": ""
                },
                {
                    "name": "-flat_namespace",
                    "content": ""
                },
                {
                    "name": "-force_flat_namespace",
                    "content": ""
                },
                {
                    "name": "-headerpad_max_install_names",
                    "content": ""
                },
                {
                    "name": "-image_base",
                    "content": ""
                },
                {
                    "name": "-init",
                    "content": ""
                },
                {
                    "name": "-install_name",
                    "content": ""
                },
                {
                    "name": "-keep_private_externs",
                    "content": ""
                },
                {
                    "name": "-multi_module",
                    "content": ""
                },
                {
                    "name": "-multiply_defined",
                    "content": ""
                },
                {
                    "name": "-multiply_defined_unused",
                    "content": ""
                },
                {
                    "name": "-noall_load",
                    "content": ""
                },
                {
                    "name": "-no_dead_strip_inits_and_terms",
                    "content": ""
                },
                {
                    "name": "-nofixprebinding",
                    "content": ""
                },
                {
                    "name": "-nomultidefs",
                    "content": ""
                },
                {
                    "name": "-noprebind",
                    "content": ""
                },
                {
                    "name": "-noseglinkedit",
                    "content": ""
                },
                {
                    "name": "-pagezero_size",
                    "content": ""
                },
                {
                    "name": "-prebind",
                    "content": ""
                },
                {
                    "name": "-prebind_all_twolevel_modules",
                    "content": ""
                },
                {
                    "name": "-private_bundle",
                    "content": ""
                },
                {
                    "name": "-read_only_relocs",
                    "content": ""
                },
                {
                    "name": "-sectalign",
                    "content": ""
                },
                {
                    "name": "-sectobjectsymbols",
                    "content": ""
                },
                {
                    "name": "-whyload",
                    "content": ""
                },
                {
                    "name": "-seg1addr",
                    "content": ""
                },
                {
                    "name": "-sectcreate",
                    "content": ""
                },
                {
                    "name": "-sectobjectsymbols",
                    "content": ""
                },
                {
                    "name": "-sectorder",
                    "content": ""
                },
                {
                    "name": "-segaddr",
                    "content": ""
                },
                {
                    "name": "-segs_read_only_addr",
                    "content": ""
                },
                {
                    "name": "-segs_read_write_addr",
                    "content": ""
                },
                {
                    "name": "-seg_addr_table",
                    "content": ""
                },
                {
                    "name": "-seg_addr_table_filename",
                    "content": ""
                },
                {
                    "name": "-seglinkedit",
                    "content": ""
                },
                {
                    "name": "-segprot",
                    "content": ""
                },
                {
                    "name": "-segs_read_only_addr",
                    "content": ""
                },
                {
                    "name": "-segs_read_write_addr",
                    "content": ""
                },
                {
                    "name": "-single_module",
                    "content": ""
                },
                {
                    "name": "-static",
                    "content": ""
                },
                {
                    "name": "-sub_library",
                    "content": ""
                },
                {
                    "name": "-sub_umbrella",
                    "content": ""
                },
                {
                    "name": "-twolevel_namespace",
                    "content": ""
                },
                {
                    "name": "-umbrella",
                    "content": ""
                },
                {
                    "name": "-undefined",
                    "content": ""
                },
                {
                    "name": "-unexported_symbols_list",
                    "content": ""
                },
                {
                    "name": "-weak_reference_mismatches",
                    "content": ""
                },
                {
                    "name": "-whatsloaded",
                    "content": "These options are passed to the Darwin linker.  The Darwin linker man page describes them\nin detail.\n\nDEC Alpha Options\n\nThese -m options are defined for the DEC Alpha implementations:\n"
                },
                {
                    "name": "-mno-soft-float",
                    "content": ""
                },
                {
                    "name": "-msoft-float",
                    "content": "Use (do not use) the hardware floating-point instructions for floating-point  operations.\nWhen  -msoft-float is specified, functions in libgcc.a are used to perform floating-point\noperations.  Unless they  are  replaced  by  routines  that  emulate  the  floating-point\noperations, or compiled in such a way as to call such emulations routines, these routines\nissue  floating-point  operations.    If you are compiling for an Alpha without floating-\npoint operations, you must ensure that the library is built so as not to call them.\n\nNote that Alpha implementations without floating-point operations are  required  to  have\nfloating-point registers.\n"
                },
                {
                    "name": "-mfp-reg",
                    "content": ""
                },
                {
                    "name": "-mno-fp-regs",
                    "content": "Generate  code  that  uses  (does not use) the floating-point register set.  -mno-fp-regs\nimplies -msoft-float.  If the floating-point register set  is  not  used,  floating-point\noperands  are  passed  in  integer  registers as if they were integers and floating-point\nresults are passed in $0 instead of $f0.  This is a non-standard calling sequence, so any\nfunction with a floating-point argument or return value  called  by  code  compiled  with\n-mno-fp-regs must also be compiled with that option.\n\nA  typical  use of this option is building a kernel that does not use, and hence need not\nsave and restore, any floating-point registers.\n"
                },
                {
                    "name": "-mieee",
                    "content": "The  Alpha  architecture  implements  floating-point  hardware  optimized   for   maximum\nperformance.  It is mostly compliant with the IEEE floating-point standard.  However, for\nfull compliance, software assistance is required.  This option generates code fully IEEE-\ncompliant  code  except  that  the  inexact-flag  is not maintained (see below).  If this\noption is turned on, the preprocessor macro \"IEEEFP\"  is  defined  during  compilation.\nThe  resulting  code  is  less  efficient  but  is able to correctly support denormalized\nnumbers and exceptional IEEE values such as not-a-number and plus/minus infinity.   Other\nAlpha compilers call this option -ieeewithnoinexact.\n\nDEBIAN   SPECIFIC:   This   option   is   on   by  default  for  alpha-linux-gnu,  unless\n-ffinite-math-only (which is part of the  -ffast-math  set)  is  specified,  because  the\nsoftware  functions  in  the GNU libc math libraries generate denormalized numbers, NaNs,\nand infs (all of which will cause a programs to  SIGFPE  when  it  attempts  to  use  the\nresults without -mieee).\n"
                },
                {
                    "name": "-mieee-with-inexact",
                    "content": "This  is  like  -mieee  except  the  generated code also maintains the IEEE inexact-flag.\nTurning on this option causes the generated code to implement fully-compliant IEEE  math.\nIn  addition to \"IEEEFP\", \"IEEEFPEXACT\" is defined as a preprocessor macro.  On some\nAlpha implementations the resulting code may execute significantly slower than  the  code\ngenerated  by default.  Since there is very little code that depends on the inexact-flag,\nyou should normally not specify this option.  Other  Alpha  compilers  call  this  option\n-ieeewithinexact.\n"
                },
                {
                    "name": "-mfp-trap-mode=_",
                    "content": "This  option  controls  what  floating-point  related  traps  are  enabled.   Other Alpha\ncompilers call this option -fptm trap-mode.  The trap mode can be  set  to  one  of  four\nvalues:\n\nn   This  is  the default (normal) setting.  The only traps that are enabled are the ones\nthat cannot be disabled in software (e.g., division by zero trap).\n\nu   In addition to the traps enabled by n, underflow traps are enabled as well.\n\nsu  Like u, but the instructions are marked to be safe for software completion (see Alpha\narchitecture manual for details).\n\nsui Like su, but inexact traps are enabled as well.\n"
                },
                {
                    "name": "-mfp-rounding-mode=_",
                    "content": "Selects the IEEE rounding mode.  Other Alpha compilers call this option  -fprm  rounding-\nmode.  The rounding-mode can be one of:\n\nn   Normal  IEEE  rounding  mode.  Floating-point numbers are rounded towards the nearest\nmachine number or towards the even machine number in case of a tie.\n\nm   Round towards minus infinity.\n\nc   Chopped rounding mode.  Floating-point numbers are rounded towards zero.\n\nd   Dynamic rounding mode.  A field in the floating-point  control  register  (fpcr,  see\nAlpha  architecture  reference  manual)  controls the rounding mode in effect.  The C\nlibrary initializes this register for rounding towards plus infinity.   Thus,  unless\nyour program modifies the fpcr, d corresponds to round towards plus infinity.\n"
                },
                {
                    "name": "-mtrap-precision=_",
                    "content": "In  the  Alpha  architecture,  floating-point  traps  are  imprecise.  This means without\nsoftware assistance it is  impossible  to  recover  from  a  floating  trap  and  program\nexecution  normally  needs  to  be  terminated.   GCC  can  generate code that can assist\noperating system trap handlers in determining the exact location that caused a  floating-\npoint  trap.   Depending  on  the  requirements  of  an  application, different levels of\nprecisions can be selected:\n\np   Program precision.  This option is the default and means  a  trap  handler  can  only\nidentify which program caused a floating-point exception.\n\nf   Function  precision.   The  trap  handler  can  determine  the function that caused a\nfloating-point exception.\n\ni   Instruction precision.  The trap handler can determine  the  exact  instruction  that\ncaused a floating-point exception.\n\nOther   Alpha   compilers   provide   the   equivalent  options  called  -scopesafe  and\n-resumptionsafe.\n"
                },
                {
                    "name": "-mieee-conformant",
                    "content": "This option marks the generated code as IEEE conformant.  You must not  use  this  option\nunless   you   also   specify   -mtrap-precision=i   and   either   -mfp-trap-mode=su  or\n-mfp-trap-mode=sui.  Its only effect is to emit  the  line  .eflag  48  in  the  function\nprologue of the generated assembly file.\n"
                },
                {
                    "name": "-mbuild-constants",
                    "content": "Normally GCC examines a 32- or 64-bit integer constant to see if it can construct it from\nsmaller constants in two or three instructions.  If it cannot, it outputs the constant as\na literal and generates code to load it from the data segment at run time.\n\nUse  this option to require GCC to construct all integer constants using code, even if it\ntakes more instructions (the maximum is six).\n\nYou typically use this option to build a shared library dynamic loader.  Itself a  shared\nlibrary, it must relocate itself in memory before it can find the variables and constants\nin its own data segment.\n"
                },
                {
                    "name": "-mbwx",
                    "content": ""
                },
                {
                    "name": "-mno-bwx",
                    "content": ""
                },
                {
                    "name": "-mcix",
                    "content": ""
                },
                {
                    "name": "-mno-cix",
                    "content": ""
                },
                {
                    "name": "-mfix",
                    "content": ""
                },
                {
                    "name": "-mno-fix",
                    "content": ""
                },
                {
                    "name": "-mmax",
                    "content": ""
                },
                {
                    "name": "-mno-max",
                    "content": "Indicate  whether  GCC  should  generate  code  to use the optional BWX, CIX, FIX and MAX\ninstruction sets.  The default is to use the instruction sets supported by the  CPU  type\nspecified  via  -mcpu=  option  or  that  of  the  CPU  on which GCC was built if none is\nspecified.\n"
                },
                {
                    "name": "-mfloat-vax",
                    "content": ""
                },
                {
                    "name": "-mfloat-ieee",
                    "content": "Generate code that uses (does not use) VAX F and G floating-point arithmetic  instead  of\nIEEE single and double precision.\n"
                },
                {
                    "name": "-mexplicit-relocs",
                    "content": ""
                },
                {
                    "name": "-mno-explicit-relocs",
                    "content": "Older  Alpha  assemblers  provided  no  way  to  generate  symbol  relocations except via\nassembler macros.  Use of these macros does not  allow  optimal  instruction  scheduling.\nGNU  binutils  as  of  version  2.12  supports  a  new syntax that allows the compiler to\nexplicitly mark which relocations should apply to which  instructions.   This  option  is\nmostly  useful for debugging, as GCC detects the capabilities of the assembler when it is\nbuilt and sets the default accordingly.\n"
                },
                {
                    "name": "-msmall-data",
                    "content": ""
                },
                {
                    "name": "-mlarge-data",
                    "content": "When -mexplicit-relocs is in effect, static data is accessed via gp-relative relocations.\nWhen -msmall-data is used, objects 8 bytes long or smaller are placed  in  a  small  data\narea  (the  \".sdata\" and \".sbss\" sections) and are accessed via 16-bit relocations off of\nthe $gp register.  This limits the size of the small data area to 64KB,  but  allows  the\nvariables to be directly accessed via a single instruction.\n\nThe  default  is  -mlarge-data.   With this option the data area is limited to just below\n2GB.  Programs that require more than 2GB of data must use \"malloc\" or \"mmap\" to allocate\nthe data in the heap instead of in the program's data segment.\n\nWhen generating code for shared libraries, -fpic implies -msmall-data and  -fPIC  implies\n-mlarge-data.\n"
                },
                {
                    "name": "-msmall-text",
                    "content": ""
                },
                {
                    "name": "-mlarge-text",
                    "content": "When  -msmall-text  is used, the compiler assumes that the code of the entire program (or\nshared library) fits in 4MB, and is thus  reachable  with  a  branch  instruction.   When\n-msmall-data  is  used, the compiler can assume that all local symbols share the same $gp\nvalue, and thus reduce the number of instructions required for a function call from 4  to\n1.\n\nThe default is -mlarge-text.\n"
                },
                {
                    "name": "-mcpu=_",
                    "content": "Set  the instruction set and instruction scheduling parameters for machine type cputype.\nYou can specify either the EV style name or the corresponding chip number.  GCC  supports\nscheduling  parameters  for  the  EV4,  EV5  and EV6 family of processors and chooses the\ndefault values for the instruction set from the processor you specify.   If  you  do  not\nspecify a processor type, GCC defaults to the processor on which the compiler was built.\n\nSupported values for cputype are\n\nev4\nev45\n21064\nSchedules as an EV4 and has no instruction set extensions.\n\nev5\n21164\nSchedules as an EV5 and has no instruction set extensions.\n\nev56\n21164a\nSchedules as an EV5 and supports the BWX extension.\n\npca56\n21164pc\n21164PC\nSchedules as an EV5 and supports the BWX and MAX extensions.\n\nev6\n21264\nSchedules as an EV6 and supports the BWX, FIX, and MAX extensions.\n\nev67\n21264a\nSchedules as an EV6 and supports the BWX, CIX, FIX, and MAX extensions.\n\nNative  toolchains  also  support  the  value native, which selects the best architecture\noption for the host processor.  -mcpu=native has no effect if GCC does not recognize  the\nprocessor.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "Set   only  the  instruction  scheduling  parameters  for  machine  type  cputype.   The\ninstruction set is not changed.\n\nNative toolchains also support the value native,  which  selects  the  best  architecture\noption for the host processor.  -mtune=native has no effect if GCC does not recognize the\nprocessor.\n"
                },
                {
                    "name": "-mmemory-latency=_",
                    "content": "Sets the latency the scheduler should assume for typical memory references as seen by the\napplication.   This  number is highly dependent on the memory access patterns used by the\napplication and the size of the external cache on the machine.\n\nValid options for time are\n\nnumber\nA decimal number representing clock cycles.\n\nL1\nL2\nL3\nmain\nThe compiler contains estimates of the number of clock cycles for \"typical\" EV4 & EV5\nhardware for the Level 1, 2 & 3 caches (also called Dcache, Scache, and  Bcache),  as\nwell as to main memory.  Note that L3 is only valid for EV5.\n\neBPF Options\n"
                },
                {
                    "name": "-mframe-limit=_",
                    "content": "This  specifies  the hard limit for frame sizes, in bytes.  Currently, the value that can\nbe specified should be less than or equal  to  32767.   Defaults  to  whatever  limit  is\nimposed by the version of the Linux kernel targeted.\n"
                },
                {
                    "name": "-mkernel=_",
                    "content": "This specifies the minimum version of the kernel that will run the compiled program.  GCC\nuses  this  version to determine which instructions to use, what kernel helpers to allow,\netc.  Currently, version can be one of 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8,  4.9,\n4.10,  4.11,  4.12, 4.13, 4.14, 4.15, 4.16, 4.17, 4.18, 4.19, 4.20, 5.0, 5.1, 5.2, latest\nand native.\n"
                },
                {
                    "name": "-mbig-endian",
                    "content": "Generate code for a big-endian target.\n"
                },
                {
                    "name": "-mlittle-endian",
                    "content": "Generate code for a little-endian target.  This is the default.\n"
                },
                {
                    "name": "-mjmpext",
                    "content": "Enable generation of extra conditional-branch  instructions.   Enabled  for  CPU  v2  and\nabove.\n"
                },
                {
                    "name": "-mjmp32",
                    "content": "Enable 32-bit jump instructions. Enabled for CPU v3 and above.\n"
                },
                {
                    "name": "-malu32",
                    "content": "Enable 32-bit ALU instructions. Enabled for CPU v3 and above.\n"
                },
                {
                    "name": "-mcpu=_",
                    "content": "This  specifies  which  version  of  the  eBPF  ISA  to target. Newer versions may not be\nsupported by all kernels. The default is v3.\n\nSupported values for version are:\n\nv1  The first stable eBPF ISA with no special features or extensions.\n\nv2  Supports the jump extensions, as in -mjmpext.\n\nv3  All features of v2, plus:\n\n-<32-bit jump operations, as in -mjmp32>\n-<32-bit ALU operations, as in -malu32>"
                },
                {
                    "name": "-mco-re",
                    "content": "Enable BPF Compile Once - Run Everywhere (CO-RE) support.  Requires  and  is  implied  by\n-gbtf.\n"
                },
                {
                    "name": "-mno-co-re",
                    "content": "Disable  BPF  Compile Once - Run Everywhere (CO-RE) support. BPF CO-RE support is enabled\nby default when generating BTF debug information for the BPF target.\n"
                },
                {
                    "name": "-mxbpf",
                    "content": "Generate code for an expanded version of BPF, which  relaxes  some  of  the  restrictions\nimposed by the BPF architecture:\n\n-<Save and restore callee-saved registers at function entry and>\nexit, respectively.\n\nFR30 Options\n\nThese options are defined specifically for the FR30 port.\n"
                },
                {
                    "name": "-msmall-model",
                    "content": "Use  the  small  address  space model.  This can produce smaller code, but it does assume\nthat all symbolic values and addresses fit into a 20-bit range.\n"
                },
                {
                    "name": "-mno-lsim",
                    "content": "Assume that runtime support has been provided and so there is  no  need  to  include  the\nsimulator library (libsim.a) on the linker command line.\n\nFT32 Options\n\nThese options are defined specifically for the FT32 port.\n"
                },
                {
                    "name": "-msim",
                    "content": "Specifies  that  the  program  will  be  run  on the simulator.  This causes an alternate\nruntime startup and library to be linked.  You must not use this option  when  generating\nprograms  that  will  run on real hardware; you must provide your own runtime library for\nwhatever I/O functions are needed.\n"
                },
                {
                    "name": "-mlra",
                    "content": "Enable Local Register Allocation.  This is still experimental for FT32, so by default the\ncompiler uses standard reload.\n"
                },
                {
                    "name": "-mnodiv",
                    "content": "Do not use div and mod instructions.\n"
                },
                {
                    "name": "-mft32b",
                    "content": "Enable use of the extended instructions of the FT32B processor.\n"
                },
                {
                    "name": "-mcompress",
                    "content": "Compress all code using the Ft32B code compression scheme.\n"
                },
                {
                    "name": "-mnopm",
                    "content": "Do not generate code that reads program memory.\n\nFRV Options\n"
                },
                {
                    "name": "-mgpr-32",
                    "content": "Only use the first 32 general-purpose registers.\n"
                },
                {
                    "name": "-mgpr-64",
                    "content": "Use all 64 general-purpose registers.\n"
                },
                {
                    "name": "-mfpr-32",
                    "content": "Use only the first 32 floating-point registers.\n"
                },
                {
                    "name": "-mfpr-64",
                    "content": "Use all 64 floating-point registers.\n"
                },
                {
                    "name": "-mhard-float",
                    "content": "Use hardware instructions for floating-point operations.\n"
                },
                {
                    "name": "-msoft-float",
                    "content": "Use library routines for floating-point operations.\n"
                },
                {
                    "name": "-malloc-cc",
                    "content": "Dynamically allocate condition code registers.\n"
                },
                {
                    "name": "-mfixed-cc",
                    "content": "Do not try to dynamically allocate condition code registers, only use \"icc0\" and \"fcc0\".\n"
                },
                {
                    "name": "-mdword",
                    "content": "Change ABI to use double word insns.\n"
                },
                {
                    "name": "-mno-dword",
                    "content": "Do not use double word instructions.\n"
                },
                {
                    "name": "-mdouble",
                    "content": "Use floating-point double instructions.\n"
                },
                {
                    "name": "-mno-double",
                    "content": "Do not use floating-point double instructions.\n"
                },
                {
                    "name": "-mmedia",
                    "content": "Use media instructions.\n"
                },
                {
                    "name": "-mno-media",
                    "content": "Do not use media instructions.\n"
                },
                {
                    "name": "-mmuladd",
                    "content": "Use multiply and add/subtract instructions.\n"
                },
                {
                    "name": "-mno-muladd",
                    "content": "Do not use multiply and add/subtract instructions.\n"
                },
                {
                    "name": "-mfdpic",
                    "content": "Select the FDPIC ABI, which uses function descriptors to represent pointers to functions.\nWithout any PIC/PIE-related options, it implies -fPIE.  With -fpic or -fpie,  it  assumes\nGOT  entries  and  small  data  are within a 12-bit range from the GOT base address; with\n-fPIC or -fPIE, GOT offsets are computed with 32 bits.   With  a  bfin-elf  target,  this\noption implies -msim.\n"
                },
                {
                    "name": "-minline-plt",
                    "content": "Enable  inlining of PLT entries in function calls to functions that are not known to bind\nlocally.  It has no effect without -mfdpic.  It's enabled by default  if  optimizing  for\nspeed  and compiling for shared libraries (i.e., -fPIC or -fpic), or when an optimization\noption such as -O3 or above is present in the command line.\n"
                },
                {
                    "name": "-mTLS",
                    "content": "Assume a large TLS segment when generating thread-local code.\n"
                },
                {
                    "name": "-mtls",
                    "content": "Do not assume a large TLS segment when generating thread-local code.\n"
                },
                {
                    "name": "-mgprel-ro",
                    "content": "Enable the use of \"GPREL\" relocations in the FDPIC ABI for data that is known  to  be  in\nread-only  sections.   It's enabled by default, except for -fpic or -fpie: even though it\nmay help make the global offset table smaller, it trades 1 instruction for 4.  With -fPIC\nor -fPIE, it trades 3 instructions for 4, one of which may be shared by multiple symbols,\nand it avoids the need for a GOT entry for the referenced symbol, so it's more likely  to\nbe a win.  If it is not, -mno-gprel-ro can be used to disable it.\n"
                },
                {
                    "name": "-multilib-library-pic",
                    "content": "Link with the (library, not FD) pic libraries.  It's implied by -mlibrary-pic, as well as\nby -fPIC and -fpic without -mfdpic.  You should never have to use it explicitly.\n"
                },
                {
                    "name": "-mlinked-fp",
                    "content": "Follow  the EABI requirement of always creating a frame pointer whenever a stack frame is\nallocated.  This option is enabled by default and can be disabled with -mno-linked-fp.\n"
                },
                {
                    "name": "-mlong-calls",
                    "content": "Use indirect addressing to call functions outside the  current  compilation  unit.   This\nallows the functions to be placed anywhere within the 32-bit address space.\n"
                },
                {
                    "name": "-malign-labels",
                    "content": "Try  to  align  labels  to an 8-byte boundary by inserting NOPs into the previous packet.\nThis option only has an effect when VLIW packing  is  enabled.   It  doesn't  create  new\npackets; it merely adds NOPs to existing ones.\n"
                },
                {
                    "name": "-mlibrary-pic",
                    "content": "Generate position-independent EABI code.\n"
                },
                {
                    "name": "-macc-4",
                    "content": "Use only the first four media accumulator registers.\n"
                },
                {
                    "name": "-macc-8",
                    "content": "Use all eight media accumulator registers.\n"
                },
                {
                    "name": "-mpack",
                    "content": "Pack VLIW instructions.\n"
                },
                {
                    "name": "-mno-pack",
                    "content": "Do not pack VLIW instructions.\n"
                },
                {
                    "name": "-mno-eflags",
                    "content": "Do not mark ABI switches in eflags.\n"
                },
                {
                    "name": "-mcond-move",
                    "content": "Enable the use of conditional-move instructions (default).\n\nThis  switch  is mainly for debugging the compiler and will likely be removed in a future\nversion.\n"
                },
                {
                    "name": "-mno-cond-move",
                    "content": "Disable the use of conditional-move instructions.\n\nThis switch is mainly for debugging the compiler and will likely be removed in  a  future\nversion.\n"
                },
                {
                    "name": "-mscc",
                    "content": "Enable the use of conditional set instructions (default).\n\nThis  switch  is mainly for debugging the compiler and will likely be removed in a future\nversion.\n"
                },
                {
                    "name": "-mno-scc",
                    "content": "Disable the use of conditional set instructions.\n\nThis switch is mainly for debugging the compiler and will likely be removed in  a  future\nversion.\n"
                },
                {
                    "name": "-mcond-exec",
                    "content": "Enable the use of conditional execution (default).\n\nThis  switch  is mainly for debugging the compiler and will likely be removed in a future\nversion.\n"
                },
                {
                    "name": "-mno-cond-exec",
                    "content": "Disable the use of conditional execution.\n\nThis switch is mainly for debugging the compiler and will likely be removed in  a  future\nversion.\n"
                },
                {
                    "name": "-mvliw-branch",
                    "content": "Run a pass to pack branches into VLIW instructions (default).\n\nThis  switch  is mainly for debugging the compiler and will likely be removed in a future\nversion.\n"
                },
                {
                    "name": "-mno-vliw-branch",
                    "content": "Do not run a pass to pack branches into VLIW instructions.\n\nThis switch is mainly for debugging the compiler and will likely be removed in  a  future\nversion.\n"
                },
                {
                    "name": "-mmulti-cond-exec",
                    "content": "Enable optimization of \"&&\" and \"||\" in conditional execution (default).\n\nThis  switch  is mainly for debugging the compiler and will likely be removed in a future\nversion.\n"
                },
                {
                    "name": "-mno-multi-cond-exec",
                    "content": "Disable optimization of \"&&\" and \"||\" in conditional execution.\n\nThis switch is mainly for debugging the compiler and will likely be removed in  a  future\nversion.\n"
                },
                {
                    "name": "-mnested-cond-exec",
                    "content": "Enable nested conditional execution optimizations (default).\n\nThis  switch  is mainly for debugging the compiler and will likely be removed in a future\nversion.\n"
                },
                {
                    "name": "-mno-nested-cond-exec",
                    "content": "Disable nested conditional execution optimizations.\n\nThis switch is mainly for debugging the compiler and will likely be removed in  a  future\nversion.\n"
                },
                {
                    "name": "-moptimize-membar",
                    "content": "This switch removes redundant \"membar\" instructions from the compiler-generated code.  It\nis enabled by default.\n"
                },
                {
                    "name": "-mno-optimize-membar",
                    "content": "This  switch  disables  the automatic removal of redundant \"membar\" instructions from the\ngenerated code.\n"
                },
                {
                    "name": "-mtomcat-stats",
                    "content": "Cause gas to print out tomcat statistics.\n"
                },
                {
                    "name": "-mcpu=_",
                    "content": "Select the processor type for which to generate code.  Possible values  are  frv,  fr550,\ntomcat, fr500, fr450, fr405, fr400, fr300 and simple.\n\nGNU/Linux Options\n\nThese -m options are defined for GNU/Linux targets:\n"
                },
                {
                    "name": "-mglibc",
                    "content": "Use   the   GNU   C   library.    This  is  the  default  except  on  *-*-linux-*uclibc*,\n*-*-linux-*musl* and *-*-linux-*android* targets.\n"
                },
                {
                    "name": "-muclibc",
                    "content": "Use uClibc C library.  This is the default on *-*-linux-*uclibc* targets.\n"
                },
                {
                    "name": "-mmusl",
                    "content": "Use the musl C library.  This is the default on *-*-linux-*musl* targets.\n"
                },
                {
                    "name": "-mbionic",
                    "content": "Use Bionic C library.  This is the default on *-*-linux-*android* targets.\n"
                },
                {
                    "name": "-mandroid",
                    "content": "Compile  code   compatible   with   Android   platform.    This   is   the   default   on\n*-*-linux-*android* targets.\n\nWhen  compiling,  this  option  enables -mbionic, -fPIC, -fno-exceptions and -fno-rtti by\ndefault.  When linking, this option makes the GCC driver pass Android-specific options to\nthe linker.  Finally, this option causes  the  preprocessor  macro  \"ANDROID\"  to  be\ndefined.\n"
                },
                {
                    "name": "-tno-android-cc",
                    "content": "Disable   compilation  effects  of  -mandroid,  i.e.,  do  not  enable  -mbionic,  -fPIC,\n-fno-exceptions and -fno-rtti by default.\n"
                },
                {
                    "name": "-tno-android-ld",
                    "content": "Disable linking effects of -mandroid, i.e., pass standard Linux linking  options  to  the\nlinker.\n\nH8/300 Options\n\nThese -m options are defined for the H8/300 implementations:\n"
                },
                {
                    "name": "-mrelax",
                    "content": "Shorten  some  address  references  at  link  time, when possible; uses the linker option\n-relax.\n"
                },
                {
                    "name": "-mh",
                    "content": ""
                },
                {
                    "name": "-ms",
                    "content": ""
                },
                {
                    "name": "-mn",
                    "content": "either with -mh or -ms.\n"
                },
                {
                    "name": "-ms2600",
                    "content": "Generate code for the H8S/2600.  This switch must be used with -ms.\n"
                },
                {
                    "name": "-mexr",
                    "content": "Extended  registers  are  stored  on  stack  before  execution  of  function with monitor\nattribute. Default option is -mexr.  This option is valid only for H8S targets.\n"
                },
                {
                    "name": "-mno-exr",
                    "content": "Extended registers are not stored on stack before  execution  of  function  with  monitor\nattribute. Default option is -mno-exr.  This option is valid only for H8S targets.\n"
                },
                {
                    "name": "-mint32",
                    "content": "Make \"int\" data 32 bits by default.\n"
                },
                {
                    "name": "-malign-300",
                    "content": "On  the H8/300H and H8S, use the same alignment rules as for the H8/300.  The default for\nthe H8/300H and H8S is to align longs  and  floats  on  4-byte  boundaries.   -malign-300\ncauses them to be aligned on 2-byte boundaries.  This option has no effect on the H8/300.\n\nHPPA Options\n\nThese -m options are defined for the HPPA family of computers:\n"
                },
                {
                    "name": "-march=_",
                    "content": "Generate  code for the specified architecture.  The choices for architecture-type are 1.0\nfor  PA  1.0,  1.1  for  PA  1.1,  and   2.0   for   PA   2.0   processors.    Refer   to\n/usr/lib/sched.models  on an HP-UX system to determine the proper architecture option for\nyour machine.  Code compiled for lower numbered architectures  runs  on  higher  numbered\narchitectures, but not the other way around.\n"
                },
                {
                    "name": "-mpa-risc-1-0",
                    "content": ""
                },
                {
                    "name": "-mpa-risc-1-1",
                    "content": ""
                },
                {
                    "name": "-mpa-risc-2-0",
                    "content": "Synonyms for -march=1.0, -march=1.1, and -march=2.0 respectively.\n"
                },
                {
                    "name": "-matomic-libcalls",
                    "content": "Generate  libcalls  for  atomic  loads  and stores when sync libcalls are disabled.  This\noption is enabled by default.  It only affects the generation of atomic libcalls  by  the\nHPPA backend.\n\nBoth  the sync and libatomic libcall implementations use locking.  As a result, processor\nstores are not atomic with respect to other atomic operations.   Processor  loads  up  to\nDImode  are  atomic with respect to other atomic operations provided they are implemented\nas a single access.\n\nThe PA-RISC architecture does not support any atomic operations in  hardware  except  for\nthe  \"ldcw\"  instruction.   Thus, all atomic support is implemented using sync and atomic\nlibcalls.  Sync libcall support is in libgcc.a.  Atomic libcall support is in libatomic.\n\nThis option generates \"atomicexchange\" calls for  atomic  stores.   It  also  provides\nspecial handling for atomic DImode accesses on 32-bit targets.\n"
                },
                {
                    "name": "-mbig-switch",
                    "content": "Does nothing.  Preserved for backward compatibility.\n"
                },
                {
                    "name": "-mcaller-copies",
                    "content": "The  caller  copies function arguments passed by hidden reference.  This option should be\nused with care as it is not compatible with the default 32-bit  runtime.   However,  only\naggregates larger than eight bytes are passed by hidden reference and the option provides\nbetter compatibility with OpenMP.\n"
                },
                {
                    "name": "-mcoherent-ldcw",
                    "content": "Use ldcw/ldcd coherent cache-control hint.\n"
                },
                {
                    "name": "-mdisable-fpregs",
                    "content": "Disable floating-point registers.  Equivalent to \"-msoft-float\".\n"
                },
                {
                    "name": "-mdisable-indexing",
                    "content": "Prevent  the compiler from using indexing address modes.  This avoids some rather obscure\nproblems when compiling MIG generated code under MACH.\n"
                },
                {
                    "name": "-mfast-indirect-calls",
                    "content": "Generate code that assumes calls never cross space boundaries.  This allows GCC  to  emit\ncode that performs faster indirect calls.\n\nThis option does not work in the presence of shared libraries or nested functions.\n"
                },
                {
                    "name": "-mfixed-range=_",
                    "content": "Generate  code treating the given register range as fixed registers.  A fixed register is\none that the register allocator cannot use.  This is useful when compiling  kernel  code.\nA  register  range  is specified as two registers separated by a dash.  Multiple register\nranges can be specified separated by a comma.\n"
                },
                {
                    "name": "-mgas",
                    "content": "Enable the use of assembler directives only GAS understands.\n"
                },
                {
                    "name": "-mgnu-ld",
                    "content": "Use options specific to GNU ld.  This  passes  -shared  to  ld  when  building  a  shared\nlibrary.   It  is  the default when GCC is configured, explicitly or implicitly, with the\nGNU linker.  This option does not affect  which  ld  is  called;  it  only  changes  what\nparameters  are  passed to that ld.  The ld that is called is determined by the --with-ld\nconfigure option, GCC's program search path, and finally by the user's PATH.  The  linker\nused  by  GCC  can be printed using which `gcc -print-prog-name=ld`.  This option is only\navailable on the 64-bit HP-UX GCC, i.e. configured with hppa*64*-*-hpux*.\n"
                },
                {
                    "name": "-mhp-ld",
                    "content": "Use options specific to HP ld.  This passes -b to ld when building a shared  library  and\npasses  +Accept  TypeMismatch  to  ld  on  all  links.   It  is  the  default when GCC is\nconfigured, explicitly or implicitly, with the HP linker.  This option  does  not  affect\nwhich  ld  is called; it only changes what parameters are passed to that ld.  The ld that\nis called is determined by the --with-ld configure option, GCC's program search path, and\nfinally by the user's PATH.  The linker used by GCC  can  be  printed  using  which  `gcc\n-print-prog-name=ld`.   This  option  is  only  available  on  the 64-bit HP-UX GCC, i.e.\nconfigured with hppa*64*-*-hpux*.\n"
                },
                {
                    "name": "-mlinker-opt",
                    "content": "Enable the optimization pass in the HP-UX linker.  Note  this  makes  symbolic  debugging\nimpossible.  It also triggers a bug in the HP-UX 8 and HP-UX 9 linkers in which they give\nbogus error messages when linking some programs.\n"
                },
                {
                    "name": "-mlong-calls",
                    "content": "Generate  code that uses long call sequences.  This ensures that a call is always able to\nreach linker generated stubs.  The default is  to  generate  long  calls  only  when  the\ndistance  from the call site to the beginning of the function or translation unit, as the\ncase may be, exceeds a predefined limit set by the branch type being  used.   The  limits\nfor  normal calls are 7,600,000 and 240,000 bytes, respectively for the PA 2.0 and PA 1.X\narchitectures.  Sibcalls are always limited at 240,000 bytes.\n\nDistances are measured from the beginning of functions when using the -ffunction-sections\noption, or when using the -mgas and -mno-portable-runtime options  together  under  HP-UX\nwith the SOM linker.\n\nIt  is normally not desirable to use this option as it degrades performance.  However, it\nmay be useful in large applications, particularly when partial linking is used  to  build\nthe application.\n\nThe types of long calls used depends on the capabilities of the assembler and linker, and\nthe  type  of  code  being  generated.   The impact on systems that support long absolute\ncalls, and long pic symbol-difference or pc-relative calls should  be  relatively  small.\nHowever, an indirect call is used on 32-bit ELF systems in pic code and it is quite long.\n"
                },
                {
                    "name": "-mlong-load-store",
                    "content": "Generate  3-instruction  load  and  store sequences as sometimes required by the HP-UX 10\nlinker.  This is equivalent to the +k option to the HP compilers.\n"
                },
                {
                    "name": "-mjump-in-delay",
                    "content": "This option is ignored and provided for compatibility purposes only.\n"
                },
                {
                    "name": "-mno-space-regs",
                    "content": "Generate code that assumes the target  has  no  space  registers.   This  allows  GCC  to\ngenerate faster indirect calls and use unscaled index address modes.\n\nSuch code is suitable for level 0 PA systems and kernels.\n"
                },
                {
                    "name": "-mordered",
                    "content": "Assume memory references are ordered and barriers are not needed.\n"
                },
                {
                    "name": "-mportable-runtime",
                    "content": "Use the portable calling conventions proposed by HP for ELF systems.\n"
                },
                {
                    "name": "-mschedule=_",
                    "content": "Schedule  code  according  to the constraints for the machine type cpu-type.  The choices\nfor cpu-type are 700 7100, 7100LC, 7200, 7300 and 8000.  Refer  to  /usr/lib/sched.models\non  an  HP-UX  system  to  determine  the proper scheduling option for your machine.  The\ndefault scheduling is 8000.\n"
                },
                {
                    "name": "-msio",
                    "content": "Generate the predefine, \"SIO\", for server IO.  The default is  -mwsio.   This  generates\nthe  predefines, \"hp9000s700\", \"hp9000s700\" and \"WSIO\", for workstation IO.  These\noptions are available under HP-UX and HI-UX.\n"
                },
                {
                    "name": "-msoft-float",
                    "content": "Generate output containing library calls for  floating  point.   Warning:  the  requisite\nlibraries  are  not  available  for  all  HPPA  targets.   Normally the facilities of the\nmachine's usual C compiler  are  used,  but  this  cannot  be  done  directly  in  cross-\ncompilation.   You  must make your own arrangements to provide suitable library functions\nfor cross-compilation.\n\n-msoft-float changes the calling convention in the output file;  therefore,  it  is  only\nuseful  if  you  compile  all  of a program with this option.  In particular, you need to\ncompile libgcc.a, the library that comes with GCC, with -msoft-float in order for this to\nwork.\n"
                },
                {
                    "name": "-msoft-mult",
                    "content": "Use software integer multiplication.\n\nThis disables the use of the \"xmpyu\" instruction.\n"
                },
                {
                    "name": "-munix=_",
                    "content": "Generate compiler predefines and select a startfile for the specified UNIX standard.  The\nchoices for unix-std are 93, 95 and 98.  93 is supported on all HP-UX  versions.   95  is\navailable  on  HP-UX  10.10  and  later.   98 is available on HP-UX 11.11 and later.  The\ndefault values are 93 for HP-UX 10.00, 95 for HP-UX 10.10 though to 11.00, and 98 for HP-\nUX 11.11 and later.\n\n-munix=93 provides the same predefines as GCC 3.3 and 3.4.  -munix=95 provides additional\npredefines for \"XOPENUNIX\" and \"XOPENSOURCEEXTENDED\",  and  the  startfile  unix95.o.\n-munix=98  provides  additional  predefines  for \"XOPENUNIX\", \"XOPENSOURCEEXTENDED\",\n\"INCLUDESTDCA1SOURCE\" and \"INCLUDEXOPENSOURCE500\", and the startfile unix98.o.\n\nIt is important to note that this option  changes  the  interfaces  for  various  library\nroutines.  It also affects the operational behavior of the C library.  Thus, extreme care\nis needed in using this option.\n\nLibrary  code that is intended to operate with more than one UNIX standard must test, set\nand restore the  variable  \"xpg4extendedmask\"  as  appropriate.   Most  GNU  software\ndoesn't provide this capability.\n"
                },
                {
                    "name": "-nolibdld",
                    "content": "Suppress  the  generation  of link options to search libdld.sl when the -static option is\nspecified on HP-UX 10 and later.\n"
                },
                {
                    "name": "-static",
                    "content": "The HP-UX implementation of setlocale in libc has a dependency on libdld.sl.  There isn't\nan archive version of libdld.sl.  Thus, when the -static  option  is  specified,  special\nlink options are needed to resolve this dependency.\n\nOn  HP-UX  10 and later, the GCC driver adds the necessary options to link with libdld.sl\nwhen the -static option is specified.  This causes the resulting binary  to  be  dynamic.\nOn  the  64-bit  port, the linkers generate dynamic binaries by default in any case.  The\n-nolibdld option can be used to prevent the GCC driver from adding these link options.\n"
                },
                {
                    "name": "-threads",
                    "content": "Add support for multithreading with the dce thread library under HP-UX.  This option sets\nflags for both the preprocessor and linker.\n\nIA-64 Options\n\nThese are the -m options defined for the Intel IA-64 architecture.\n"
                },
                {
                    "name": "-mbig-endian",
                    "content": "Generate code for a big-endian target.  This is the default for HP-UX.\n"
                },
                {
                    "name": "-mlittle-endian",
                    "content": "Generate code for a little-endian target.  This is the default for AIX5 and GNU/Linux.\n"
                },
                {
                    "name": "-mgnu-as",
                    "content": ""
                },
                {
                    "name": "-mno-gnu-as",
                    "content": "Generate (or don't) code for the GNU assembler.  This is the default.\n"
                },
                {
                    "name": "-mgnu-ld",
                    "content": ""
                },
                {
                    "name": "-mno-gnu-ld",
                    "content": "Generate (or don't) code for the GNU linker.  This is the default.\n"
                },
                {
                    "name": "-mno-pic",
                    "content": "Generate code that does not use a global pointer register.  The result  is  not  position\nindependent code, and violates the IA-64 ABI.\n"
                },
                {
                    "name": "-mvolatile-asm-stop",
                    "content": ""
                },
                {
                    "name": "-mno-volatile-asm-stop",
                    "content": "Generate (or don't) a stop bit immediately before and after volatile asm statements.\n"
                },
                {
                    "name": "-mregister-names",
                    "content": ""
                },
                {
                    "name": "-mno-register-names",
                    "content": "Generate  (or don't) in, loc, and out register names for the stacked registers.  This may\nmake assembler output more readable.\n"
                },
                {
                    "name": "-mno-sdata",
                    "content": ""
                },
                {
                    "name": "-msdata",
                    "content": "Disable (or enable) optimizations that use the small data section.  This  may  be  useful\nfor working around optimizer bugs.\n"
                },
                {
                    "name": "-mconstant-gp",
                    "content": "Generate  code  that  uses  a  single constant global pointer value.  This is useful when\ncompiling kernel code.\n"
                },
                {
                    "name": "-mauto-pic",
                    "content": "Generate code that is self-relocatable.  This implies -mconstant-gp.  This is useful when\ncompiling firmware code.\n"
                },
                {
                    "name": "-minline-float-divide-min-latency",
                    "content": "Generate code for inline divides of  floating-point  values  using  the  minimum  latency\nalgorithm.\n"
                },
                {
                    "name": "-minline-float-divide-max-throughput",
                    "content": "Generate  code  for  inline divides of floating-point values using the maximum throughput\nalgorithm.\n"
                },
                {
                    "name": "-mno-inline-float-divide",
                    "content": "Do not generate inline code for divides of floating-point values.\n"
                },
                {
                    "name": "-minline-int-divide-min-latency",
                    "content": "Generate code for inline divides of integer values using the minimum latency algorithm.\n"
                },
                {
                    "name": "-minline-int-divide-max-throughput",
                    "content": "Generate code  for  inline  divides  of  integer  values  using  the  maximum  throughput\nalgorithm.\n"
                },
                {
                    "name": "-mno-inline-int-divide",
                    "content": "Do not generate inline code for divides of integer values.\n"
                },
                {
                    "name": "-minline-sqrt-min-latency",
                    "content": "Generate code for inline square roots using the minimum latency algorithm.\n"
                },
                {
                    "name": "-minline-sqrt-max-throughput",
                    "content": "Generate code for inline square roots using the maximum throughput algorithm.\n"
                },
                {
                    "name": "-mno-inline-sqrt",
                    "content": "Do not generate inline code for \"sqrt\".\n"
                },
                {
                    "name": "-mfused-madd",
                    "content": ""
                },
                {
                    "name": "-mno-fused-madd",
                    "content": "Do   (don't)  generate  code  that  uses  the  fused  multiply/add  or  multiply/subtract\ninstructions.  The default is to use these instructions.\n"
                },
                {
                    "name": "-mno-dwarf2-asm",
                    "content": ""
                },
                {
                    "name": "-mdwarf2-asm",
                    "content": "Don't (or do) generate assembler code for the DWARF line number debugging info.  This may\nbe useful when not using the GNU assembler.\n"
                },
                {
                    "name": "-mearly-stop-bits",
                    "content": ""
                },
                {
                    "name": "-mno-early-stop-bits",
                    "content": "Allow stop bits to be placed earlier than  immediately  preceding  the  instruction  that\ntriggered  the stop bit.  This can improve instruction scheduling, but does not always do\nso.\n"
                },
                {
                    "name": "-mfixed-range=_",
                    "content": "Generate code treating the given register range as fixed registers.  A fixed register  is\none  that  the register allocator cannot use.  This is useful when compiling kernel code.\nA register range is specified as two registers separated by a  dash.   Multiple  register\nranges can be specified separated by a comma.\n"
                },
                {
                    "name": "-mtls-size=_",
                    "content": "Specify bit size of immediate TLS offsets.  Valid values are 14, 22, and 64.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "Tune the instruction scheduling for a particular CPU, Valid values are itanium, itanium1,\nmerced, itanium2, and mckinley.\n"
                },
                {
                    "name": "-milp32",
                    "content": ""
                },
                {
                    "name": "-mlp64",
                    "content": "Generate  code for a 32-bit or 64-bit environment.  The 32-bit environment sets int, long\nand pointer to 32 bits.  The 64-bit environment sets int to 32 bits and long and  pointer\nto 64 bits.  These are HP-UX specific flags.\n"
                },
                {
                    "name": "-mno-sched-br-data-spec",
                    "content": ""
                },
                {
                    "name": "-msched-br-data-spec",
                    "content": "(Dis/En)able  data  speculative  scheduling before reload.  This results in generation of\n\"ld.a\" instructions and the corresponding check instructions  (\"ld.c\"  /  \"chk.a\").   The\ndefault setting is disabled.\n"
                },
                {
                    "name": "-msched-ar-data-spec",
                    "content": ""
                },
                {
                    "name": "-mno-sched-ar-data-spec",
                    "content": "(En/Dis)able  data  speculative  scheduling  after reload.  This results in generation of\n\"ld.a\" instructions and the corresponding check instructions  (\"ld.c\"  /  \"chk.a\").   The\ndefault setting is enabled.\n"
                },
                {
                    "name": "-mno-sched-control-spec",
                    "content": ""
                },
                {
                    "name": "-msched-control-spec",
                    "content": "(Dis/En)able  control  speculative  scheduling.   This  feature  is available only during\nregion scheduling (i.e. before  reload).   This  results  in  generation  of  the  \"ld.s\"\ninstructions  and  the  corresponding check instructions \"chk.s\".  The default setting is\ndisabled.\n"
                },
                {
                    "name": "-msched-br-in-data-spec",
                    "content": ""
                },
                {
                    "name": "-mno-sched-br-in-data-spec",
                    "content": "(En/Dis)able speculative scheduling of the instructions that are dependent  on  the  data\nspeculative  loads  before  reload.   This  is  effective  only with -msched-br-data-spec\nenabled.  The default setting is enabled.\n"
                },
                {
                    "name": "-msched-ar-in-data-spec",
                    "content": ""
                },
                {
                    "name": "-mno-sched-ar-in-data-spec",
                    "content": "(En/Dis)able speculative scheduling of the instructions that are dependent  on  the  data\nspeculative  loads  after  reload.   This  is  effective  only  with -msched-ar-data-spec\nenabled.  The default setting is enabled.\n"
                },
                {
                    "name": "-msched-in-control-spec",
                    "content": ""
                },
                {
                    "name": "-mno-sched-in-control-spec",
                    "content": "(En/Dis)able speculative scheduling of the instructions that are dependent on the control\nspeculative loads.  This  is  effective  only  with  -msched-control-spec  enabled.   The\ndefault setting is enabled.\n"
                },
                {
                    "name": "-mno-sched-prefer-non-data-spec-insns",
                    "content": ""
                },
                {
                    "name": "-msched-prefer-non-data-spec-insns",
                    "content": "If  enabled,  data-speculative  instructions are chosen for schedule only if there are no\nother choices at the moment.  This makes the  use  of  the  data  speculation  much  more\nconservative.  The default setting is disabled.\n"
                },
                {
                    "name": "-mno-sched-prefer-non-control-spec-insns",
                    "content": ""
                },
                {
                    "name": "-msched-prefer-non-control-spec-insns",
                    "content": "If enabled, control-speculative instructions are chosen for schedule only if there are no\nother  choices  at  the  moment.  This makes the use of the control speculation much more\nconservative.  The default setting is disabled.\n"
                },
                {
                    "name": "-mno-sched-count-spec-in-critical-path",
                    "content": ""
                },
                {
                    "name": "-msched-count-spec-in-critical-path",
                    "content": "If  enabled,  speculative  dependencies  are  considered  during   computation   of   the\ninstructions  priorities.  This makes the use of the speculation a bit more conservative.\nThe default setting is disabled.\n"
                },
                {
                    "name": "-msched-spec-ldc",
                    "content": "Use a simple data speculation check.  This option is on by default.\n"
                },
                {
                    "name": "-msched-control-spec-ldc",
                    "content": "Use a simple check for control speculation.  This option is on by default.\n"
                },
                {
                    "name": "-msched-stop-bits-after-every-cycle",
                    "content": "Place a stop bit after every cycle when scheduling.  This option is on by default.\n"
                },
                {
                    "name": "-msched-fp-mem-deps-zero-cost",
                    "content": "Assume that floating-point stores and loads are not  likely  to  cause  a  conflict  when\nplaced into the same instruction group.  This option is disabled by default.\n"
                },
                {
                    "name": "-msel-sched-dont-check-control-spec",
                    "content": "Generate  checks  for control speculation in selective scheduling.  This flag is disabled\nby default.\n"
                },
                {
                    "name": "-msched-max-memory-insns=_",
                    "content": "Limit on the number of memory insns per  instruction  group,  giving  lower  priority  to\nsubsequent  memory insns attempting to schedule in the same instruction group. Frequently\nuseful to prevent cache bank conflicts.  The default value is 1.\n"
                },
                {
                    "name": "-msched-max-memory-insns-hard-limit",
                    "content": "Makes the limit specified by msched-max-memory-insns a hard limit, disallowing more  than\nthat  number  in an instruction group.  Otherwise, the limit is \"soft\", meaning that non-\nmemory operations are preferred when the limit is  reached,  but  memory  operations  may\nstill be scheduled.\n\nLM32 Options\n\nThese -m options are defined for the LatticeMico32 architecture:\n"
                },
                {
                    "name": "-mbarrel-shift-enabled",
                    "content": "Enable barrel-shift instructions.\n"
                },
                {
                    "name": "-mdivide-enabled",
                    "content": "Enable divide and modulus instructions.\n"
                },
                {
                    "name": "-mmultiply-enabled",
                    "content": "Enable multiply instructions.\n"
                },
                {
                    "name": "-msign-extend-enabled",
                    "content": "Enable sign extend instructions.\n"
                },
                {
                    "name": "-muser-enabled",
                    "content": "Enable user-defined instructions.\n\nLoongArch Options\n\nThese command-line options are defined for LoongArch targets:\n"
                },
                {
                    "name": "-march=_",
                    "content": "Generate  instructions  for  the  machine type cpu-type.  In contrast to -mtune=cpu-type,\nwhich merely tunes the generated code for the specified cpu-type, -march=cpu-type  allows\nGCC  to generate code that may not run at all on processors other than the one indicated.\nSpecifying -march=cpu-type implies -mtune=cpu-type, except where noted otherwise.\n\nThe choices for cpu-type are:\n\nnative\nThis selects the CPU to generate code for at  compilation  time  by  determining  the\nprocessor type of the compiling machine.  Using -march=native enables all instruction\nsubsets  supported  by the local machine (hence the result might not run on different\nmachines).  Using -mtune=native produces code optimized for the local  machine  under\nthe constraints of the selected instruction set.\n\nloongarch64\nA generic CPU with 64-bit extensions.\n\nla464\nLoongArch LA464 CPU with LBT, LSX, LASX, LVZ.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "Optimize the output for the given processor, specified by microarchitecture name.\n"
                },
                {
                    "name": "-mabi=_",
                    "content": "Generate code for the specified calling convention.  base-abi-type can be one of:\n\nlp64d\nUses  64-bit  general  purpose  registers  and 32/64-bit floating-point registers for\nparameter passing.  Data model is LP64, where int is 32  bits,  while  long  int  and\npointers are 64 bits.\n\nlp64f\nUses  64-bit  general  purpose  registers  and  32-bit  floating-point  registers for\nparameter passing.  Data model is LP64, where int is 32  bits,  while  long  int  and\npointers are 64 bits.\n\nlp64s\nUses  64-bit  general purpose registers and no floating-point registers for parameter\npassing.  Data model is LP64, where int is 32 bits, while long int and  pointers  are\n64 bits.\n"
                },
                {
                    "name": "-mfpu=_",
                    "content": "Generate code for the specified FPU type, which can be one of:\n\n64  Allow  the  use  of  hardware  floating-point  instructions  for  32-bit  and  64-bit\noperations.\n\n32  Allow the use of hardware floating-point instructions for 32-bit operations.\n\nnone\n0   Prevent the use of hardware floating-point instructions.\n"
                },
                {
                    "name": "-msoft-float",
                    "content": "Force -mfpu=none and prevents the use of floating-point registers for parameter  passing.\nThis option may change the target ABI.\n"
                },
                {
                    "name": "-msingle-float",
                    "content": "Force  -mfpu=32  and  allow  the  use  of  32-bit  floating-point registers for parameter\npassing.  This option may change the target ABI.\n"
                },
                {
                    "name": "-mdouble-float",
                    "content": "Force -mfpu=64 and allow the use of  32/64-bit  floating-point  registers  for  parameter\npassing.  This option may change the target ABI.\n"
                },
                {
                    "name": "-mbranch-cost=_",
                    "content": "Set the cost of branches to roughly n instructions.\n"
                },
                {
                    "name": "-mcheck-zero-division",
                    "content": ""
                },
                {
                    "name": "-mno-check-zero-divison",
                    "content": "Trap (do not trap) on integer division by zero.  The default is -mcheck-zero-division for\n-O0 or -Og, and -mno-check-zero-division for other optimization levels.\n"
                },
                {
                    "name": "-mcond-move-int",
                    "content": ""
                },
                {
                    "name": "-mno-cond-move-int",
                    "content": "Conditional  moves for integral data in general-purpose registers are enabled (disabled).\nThe default is -mcond-move-int.\n"
                },
                {
                    "name": "-mcond-move-float",
                    "content": ""
                },
                {
                    "name": "-mno-cond-move-float",
                    "content": "Conditional moves for floating-point registers are enabled (disabled).   The  default  is\n-mcond-move-float.\n"
                },
                {
                    "name": "-mmemcpy",
                    "content": ""
                },
                {
                    "name": "-mno-memcpy",
                    "content": "Force  (do  not  force)  the use of \"memcpy\" for non-trivial block moves.  The default is\n-mno-memcpy, which allows GCC to inline most constant-sized copies.  Setting optimization\nlevel to -Os also forces the use of \"memcpy\", but -mno-memcpy may override this  behavior\nif explicitly specified, regardless of the order these options on the command line.\n"
                },
                {
                    "name": "-mstrict-align",
                    "content": ""
                },
                {
                    "name": "-mno-strict-align",
                    "content": "Avoid  or  allow  generating  memory accesses that may not be aligned on a natural object\nboundary   as   described   in   the   architecture   specification.   The   default   is\n-mno-strict-align.\n"
                },
                {
                    "name": "-msmall-data-limit=_",
                    "content": "Put  global  and  static  data  smaller than number bytes into a special section (on some\ntargets).  The default value is 0.\n"
                },
                {
                    "name": "-mmax-inline-memcpy-size=_",
                    "content": "Inline all block moves (such as calls to \"memcpy\" or structure copies) less than or equal\nto n bytes.  The default value of n is 1024.\n"
                },
                {
                    "name": "-mcmodel=_",
                    "content": "Set the code model to one of:\n\ntiny-static (Not implemented yet)\ntiny (Not implemented yet)\nnormal\nThe text segment must be within 128MB addressing space.  The  data  segment  must  be\nwithin 2GB addressing space.\n\nmedium\nThe text segment and data segment must be within 2GB addressing space.\n\nlarge (Not implemented yet)\nextreme\nThis  mode  does  not  limit  the  size  of  the  code segment and data segment.  The\n-mcmodel=extreme option is incompatible with -fplt and -mno-explicit-relocs.\n\nThe default code model is \"normal\".\n"
                },
                {
                    "name": "-mexplicit-relocs",
                    "content": ""
                },
                {
                    "name": "-mno-explicit-relocs",
                    "content": "Use or do not use assembler relocation operators when dealing  with  symbolic  addresses.\nThe  alternative  is  to  use  assembler  macros  instead,  which  may  limit instruction\nscheduling but allow linker relaxation.  The default value for the option  is  determined\nwith  the  assembler  capability  detected  during  GCC  build-time  and  the  setting of\n\"-mrelax\":  \"-mexplicit-relocs\"  if  the  assembler  supports  relocation  operators  but\n\"-mrelax\" is not enabled, \"-mno-explicit-relocs\" otherwise.\n"
                },
                {
                    "name": "-mdirect-extern-access",
                    "content": ""
                },
                {
                    "name": "-mno-direct-extern-access",
                    "content": "Do   not   use   or   use   GOT   to   access   external   symbols.    The   default   is\n-mno-direct-extern-access: GOT is used for external symbols with default visibility,  but\nnot used for other external symbols.\n\nWith  -mdirect-extern-access,  GOT is not used and all external symbols are PC-relatively\naddressed.  It is only suitable for environments where no dynamic link is performed, like\nfirmwares,   OS   kernels,   executables   linked   with    -static    or    -static-pie.\n-mdirect-extern-access is not compatible with -fPIC or -fpic.\n"
                },
                {
                    "name": "-mrelax",
                    "content": ""
                },
                {
                    "name": "-mno-relax",
                    "content": "Take  (do  not take) advantage of linker relaxations.  If -mpass-mrelax-to-as is enabled,\nthis option is also passed to the assembler.  The default is determined during GCC build-\ntime by detecting corresponding assembler support: -mrelax if the assembler supports both\nthe -mrelax option and the conditional branch relaxation (it's required or  the  \".align\"\ndirectives  and conditional branch instructions in the assembly code outputted by GCC may\nbe rejected by the assembler because of a relocation overflow), -mno-relax otherwise.\n"
                },
                {
                    "name": "-mpass-mrelax-to-as",
                    "content": ""
                },
                {
                    "name": "-mno-pass-mrelax-to-as",
                    "content": "Pass (do not pass) the -mrelax or -mno-relax option to the  assembler.   The  default  is\ndetermined   during   GCC   build-time  by  detecting  corresponding  assembler  support:\n-mpass-mrelax-to-as if the assembler supports the -mrelax option,  -mno-pass-mrelax-to-as\notherwise.  This option is mostly useful for debugging, or interoperation with assemblers\ndifferent from the build-time one.\n\nM32C Options\n"
                },
                {
                    "name": "-mcpu=_",
                    "content": "Select  the  CPU  for  which  code is generated.  name may be one of r8c for the R8C/Tiny\nseries, m16c for the M16C (up to /60) series, m32cm for the M16C/80 series, or  m32c  for\nthe M32C/80 series.\n"
                },
                {
                    "name": "-msim",
                    "content": "Specifies  that  the  program  will  be  run  on the simulator.  This causes an alternate\nruntime library to be linked in which supports, for example, file I/O.  You must not  use\nthis  option  when  generating  programs that will run on real hardware; you must provide\nyour own runtime library for whatever I/O functions are needed.\n"
                },
                {
                    "name": "-memregs=_",
                    "content": "Specifies the number of memory-based pseudo-registers GCC uses  during  code  generation.\nThese pseudo-registers are used like real registers, so there is a tradeoff between GCC's\nability  to  fit  the code into available registers, and the performance penalty of using\nmemory instead of registers.  Note that all modules in a program must  be  compiled  with\nthe same value for this option.  Because of that, you must not use this option with GCC's\ndefault runtime libraries.\n\nM32R/D Options\n\nThese -m options are defined for Renesas M32R/D architectures:\n"
                },
                {
                    "name": "-m32r2",
                    "content": "Generate code for the M32R/2.\n"
                },
                {
                    "name": "-m32rx",
                    "content": "Generate code for the M32R/X.\n"
                },
                {
                    "name": "-m32r",
                    "content": "Generate code for the M32R.  This is the default.\n"
                },
                {
                    "name": "-mmodel=small",
                    "content": "Assume  all  objects  live  in  the  lower 16MB of memory (so that their addresses can be\nloaded with the \"ld24\" instruction), and assume all subroutines are  reachable  with  the\n\"bl\" instruction.  This is the default.\n\nThe addressability of a particular object can be set with the \"model\" attribute.\n"
                },
                {
                    "name": "-mmodel=medium",
                    "content": "Assume  objects  may  be  anywhere  in  the  32-bit address space (the compiler generates\n\"seth/add3\" instructions to  load  their  addresses),  and  assume  all  subroutines  are\nreachable with the \"bl\" instruction.\n"
                },
                {
                    "name": "-mmodel=large",
                    "content": "Assume  objects  may  be  anywhere  in  the  32-bit address space (the compiler generates\n\"seth/add3\" instructions to load their addresses), and  assume  subroutines  may  not  be\nreachable   with   the   \"bl\"   instruction  (the  compiler  generates  the  much  slower\n\"seth/add3/jl\" instruction sequence).\n"
                },
                {
                    "name": "-msdata=none",
                    "content": "Disable use of the small data area.  Variables are put into one of  \".data\",  \".bss\",  or\n\".rodata\" (unless the \"section\" attribute has been specified).  This is the default.\n\nThe small data area consists of sections \".sdata\" and \".sbss\".  Objects may be explicitly\nput in the small data area with the \"section\" attribute using one of these sections.\n"
                },
                {
                    "name": "-msdata=sdata",
                    "content": "Put small global and static data in the small data area, but do not generate special code\nto reference them.\n"
                },
                {
                    "name": "-msdata=use",
                    "content": "Put  small  global  and  static  data  in  the  small  data  area,  and  generate special\ninstructions to reference them.\n"
                },
                {
                    "name": "-G _",
                    "content": "Put global and static objects less than or equal to num bytes into the small data or  BSS\nsections instead of the normal data or BSS sections.  The default value of num is 8.  The\n-msdata option must be set to one of sdata or use for this option to have any effect.\n\nAll  modules  should  be  compiled  with the same -G num value.  Compiling with different\nvalues  of  num  may  or  may  not  work;  if  it  doesn't  the  linker  gives  an  error\nmessage---incorrect code is not generated.\n",
                    "flag": "-G"
                },
                {
                    "name": "-mdebug",
                    "content": "Makes  the  M32R-specific code in the compiler display some statistics that might help in\ndebugging programs.\n"
                },
                {
                    "name": "-malign-loops",
                    "content": "Align all loops to a 32-byte boundary.\n"
                },
                {
                    "name": "-mno-align-loops",
                    "content": "Do not enforce a 32-byte alignment for loops.  This is the default.\n"
                },
                {
                    "name": "-missue-rate=_",
                    "content": "Issue number instructions per cycle.  number can only be 1 or 2.\n"
                },
                {
                    "name": "-mbranch-cost=_",
                    "content": "number can only be 1 or 2.  If it is 1 then branches are preferred over conditional code,\nif it is 2, then the opposite applies.\n"
                },
                {
                    "name": "-mflush-trap=_",
                    "content": "Specifies the trap number to use to flush the cache.  The default is 12.   Valid  numbers\nare between 0 and 15 inclusive.\n"
                },
                {
                    "name": "-mno-flush-trap",
                    "content": "Specifies that the cache cannot be flushed by using a trap.\n"
                },
                {
                    "name": "-mflush-func=_",
                    "content": "Specifies  the  name  of  the  operating system function to call to flush the cache.  The\ndefault is flushcache, but a function call is only used if a trap is not available.\n"
                },
                {
                    "name": "-mno-flush-func",
                    "content": "Indicates that there is no OS function for flushing the cache.\n\nM680x0 Options\n\nThese are the -m options defined for M680x0 and ColdFire processors.   The  default  settings\ndepend  on which architecture was selected when the compiler was configured; the defaults for\nthe most common choices are given below.\n"
                },
                {
                    "name": "-march=_",
                    "content": "Generate  code  for  a  specific  M680x0  or  ColdFire  instruction   set   architecture.\nPermissible  values  of  arch  for  M680x0 architectures are: 68000, 68010, 68020, 68030,\n68040, 68060 and cpu32.  ColdFire architectures are selected according to Freescale's ISA\nclassification and the permissible values are: isaa, isaaplus, isab and isac.\n\nGCC defines a macro \"mcfarch\" whenever it is generating code for a  ColdFire  target.\nThe arch in this macro is one of the -march arguments given above.\n\nWhen  used  together,  -march  and  -mtune  select  code that runs on a family of similar\nprocessors but that is optimized for a particular microarchitecture.\n"
                },
                {
                    "name": "-mcpu=_",
                    "content": "Generate code for a specific M680x0 or ColdFire processor.  The M680x0 cpus  are:  68000,\n68010,  68020,  68030, 68040, 68060, 68302, 68332 and cpu32.  The ColdFire cpus are given\nby the table below, which also classifies the CPUs into families:\n\nFamily : -mcpu arguments\n51 : 51 51ac 51ag 51cn 51em 51je 51jf 51jg 51jm 51mm 51qe 51qm\n5206 : 5202 5204 5206\n5206e : 5206e\n5208 : 5207 5208\n5211a : 5210a 5211a\n5213 : 5211 5212 5213\n5216 : 5214 5216\n52235 : 52230 52231 52232 52233 52234 52235\n5225 : 5224 5225\n52259 : 52252 52254 52255 52256 52258 52259\n5235 : 5232 5233 5234 5235 523x\n5249 : 5249\n5250 : 5250\n5271 : 5270 5271\n5272 : 5272\n5275 : 5274 5275\n5282 : 5280 5281 5282 528x\n53017 : 53011 53012 53013 53014 53015 53016 53017\n5307 : 5307\n5329 : 5327 5328 5329 532x\n5373 : 5372 5373 537x\n5407 : 5407\n5475 : 5470 5471 5472 5473 5474 5475 547x 5480 5481 5482 5483 5484 5485\n\n-mcpu=cpu overrides -march=arch if arch is compatible with cpu.   Other  combinations  of\n-mcpu and -march are rejected.\n\nGCC  defines  the  macro  \"mcfcpucpu\"  when ColdFire target cpu is selected.  It also\ndefines \"mcffamilyfamily\", where the value of family is given by the table above.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "Tune the code for a particular microarchitecture within the constraints set by -march and\n-mcpu.  The M680x0 microarchitectures are: 68000, 68010, 68020, 68030, 68040,  68060  and\ncpu32.  The ColdFire microarchitectures are: cfv1, cfv2, cfv3, cfv4 and cfv4e.\n\nYou  can  also  use  -mtune=68020-40 for code that needs to run relatively well on 68020,\n68030 and 68040 targets.  -mtune=68020-60 is similar but includes 68060 targets as  well.\nThese  two  options  select  the  same  tuning  decisions  as  -m68020-40  and -m68020-60\nrespectively.\n\nGCC defines the macros \"mcarch\" and \"mcarch\" when  tuning  for  680x0  architecture\narch.  It also defines \"mcarch\" unless either -ansi or a non-GNU -std option is used.  If\nGCC  is  tuning  for  a  range  of  architectures,  as  selected  by  -mtune=68020-40  or\n-mtune=68020-60, it defines the macros for every architecture in the range.\n\nGCC also defines the macro \"muarch\" when tuning for ColdFire microarchitecture uarch,\nwhere uarch is one of the arguments given above.\n"
                },
                {
                    "name": "-m68000",
                    "content": ""
                },
                {
                    "name": "-mc68000",
                    "content": "Generate output for a 68000.  This is the default when the  compiler  is  configured  for\n68000-based systems.  It is equivalent to -march=68000.\n\nUse  this  option  for  microcontrollers with a 68000 or EC000 core, including the 68008,\n68302, 68306, 68307, 68322, 68328 and 68356.\n"
                },
                {
                    "name": "-m68010",
                    "content": "Generate output for a 68010.  This is the default when the  compiler  is  configured  for\n68010-based systems.  It is equivalent to -march=68010.\n"
                },
                {
                    "name": "-m68020",
                    "content": ""
                },
                {
                    "name": "-mc68020",
                    "content": "Generate  output  for  a  68020.  This is the default when the compiler is configured for\n68020-based systems.  It is equivalent to -march=68020.\n"
                },
                {
                    "name": "-m68030",
                    "content": "Generate output for a 68030.  This is the default when the  compiler  is  configured  for\n68030-based systems.  It is equivalent to -march=68030.\n"
                },
                {
                    "name": "-m68040",
                    "content": "Generate  output  for  a  68040.  This is the default when the compiler is configured for\n68040-based systems.  It is equivalent to -march=68040.\n\nThis option inhibits the use of 68881/68882 instructions that  have  to  be  emulated  by\nsoftware on the 68040.  Use this option if your 68040 does not have code to emulate those\ninstructions.\n"
                },
                {
                    "name": "-m68060",
                    "content": "Generate  output  for  a  68060.  This is the default when the compiler is configured for\n68060-based systems.  It is equivalent to -march=68060.\n\nThis option inhibits the use of 68020  and  68881/68882  instructions  that  have  to  be\nemulated  by  software on the 68060.  Use this option if your 68060 does not have code to\nemulate those instructions.\n"
                },
                {
                    "name": "-mcpu32",
                    "content": "Generate output for a CPU32.  This is the default when the  compiler  is  configured  for\nCPU32-based systems.  It is equivalent to -march=cpu32.\n\nUse  this  option  for microcontrollers with a CPU32 or CPU32+ core, including the 68330,\n68331, 68332, 68333, 68334, 68336, 68340, 68341, 68349 and 68360.\n"
                },
                {
                    "name": "-m5200",
                    "content": "Generate output for a 520X ColdFire CPU.  This  is  the  default  when  the  compiler  is\nconfigured for 520X-based systems.  It is equivalent to -mcpu=5206, and is now deprecated\nin favor of that option.\n\nUse  this  option  for  microcontroller with a 5200 core, including the MCF5202, MCF5203,\nMCF5204 and MCF5206.\n"
                },
                {
                    "name": "-m5206e",
                    "content": "Generate output for a 5206e ColdFire CPU.  The option is now deprecated in favor  of  the\nequivalent -mcpu=5206e.\n"
                },
                {
                    "name": "-m528x",
                    "content": "Generate  output  for a member of the ColdFire 528X family.  The option is now deprecated\nin favor of the equivalent -mcpu=528x.\n"
                },
                {
                    "name": "-m5307",
                    "content": "Generate output for a ColdFire 5307 CPU.  The option is now deprecated in  favor  of  the\nequivalent -mcpu=5307.\n"
                },
                {
                    "name": "-m5407",
                    "content": "Generate  output  for  a ColdFire 5407 CPU.  The option is now deprecated in favor of the\nequivalent -mcpu=5407.\n"
                },
                {
                    "name": "-mcfv4e",
                    "content": "Generate output for a ColdFire V4e family CPU (e.g. 547x/548x).   This  includes  use  of\nhardware floating-point instructions.  The option is equivalent to -mcpu=547x, and is now\ndeprecated in favor of that option.\n"
                },
                {
                    "name": "-m68020-40",
                    "content": "Generate  output for a 68040, without using any of the new instructions.  This results in\ncode that can run relatively efficiently on either a 68020/68881 or a 68030 or  a  68040.\nThe generated code does use the 68881 instructions that are emulated on the 68040.\n\nThe option is equivalent to -march=68020 -mtune=68020-40.\n"
                },
                {
                    "name": "-m68020-60",
                    "content": "Generate  output for a 68060, without using any of the new instructions.  This results in\ncode that can run relatively efficiently on either a 68020/68881 or a 68030 or  a  68040.\nThe generated code does use the 68881 instructions that are emulated on the 68060.\n\nThe option is equivalent to -march=68020 -mtune=68020-60.\n"
                },
                {
                    "name": "-mhard-float",
                    "content": ""
                },
                {
                    "name": "-m68881",
                    "content": "Generate  floating-point  instructions.  This is the default for 68020 and above, and for\nColdFire devices that have an FPU.  It  defines  the  macro  \"HAVE68881\"  on  M680x0\ntargets and \"mcffpu\" on ColdFire targets.\n"
                },
                {
                    "name": "-msoft-float",
                    "content": "Do  not  generate  floating-point  instructions;  use library calls instead.  This is the\ndefault for 68000, 68010, and 68832 targets.  It is also the default for ColdFire devices\nthat have no FPU.\n"
                },
                {
                    "name": "-mdiv",
                    "content": ""
                },
                {
                    "name": "-mno-div",
                    "content": "Generate (do not generate) ColdFire  hardware  divide  and  remainder  instructions.   If\n-march  is  used  without -mcpu, the default is \"on\" for ColdFire architectures and \"off\"\nfor M680x0 architectures.  Otherwise, the default is taken from the  target  CPU  (either\nthe  default  CPU, or the one specified by -mcpu).  For example, the default is \"off\" for\n-mcpu=5206 and \"on\" for -mcpu=5206e.\n\nGCC defines the macro \"mcfhwdiv\" when this option is enabled.\n"
                },
                {
                    "name": "-mshort",
                    "content": "Consider type \"int\" to be 16 bits  wide,  like  \"short  int\".   Additionally,  parameters\npassed  on  the  stack  are  also  aligned to a 16-bit boundary even on targets whose API\nmandates promotion to 32-bit.\n"
                },
                {
                    "name": "-mno-short",
                    "content": "Do not consider type \"int\" to be 16 bits wide.  This is the default.\n"
                },
                {
                    "name": "-mnobitfield",
                    "content": ""
                },
                {
                    "name": "-mno-bitfield",
                    "content": "Do not use the bit-field instructions.  The -m68000, -mcpu32  and  -m5200  options  imply\n-mnobitfield.\n"
                },
                {
                    "name": "-mbitfield",
                    "content": "Do  use  the bit-field instructions.  The -m68020 option implies -mbitfield.  This is the\ndefault if you use a configuration designed for a 68020.\n"
                },
                {
                    "name": "-mrtd",
                    "content": "Use a different function-calling convention, in which functions that take a fixed  number\nof  arguments  return  with  the  \"rtd\"  instruction,  which  pops  their arguments while\nreturning.  This saves one instruction in the caller since there is no need  to  pop  the\narguments there.\n\nThis calling convention is incompatible with the one normally used on Unix, so you cannot\nuse it if you need to call libraries compiled with the Unix compiler.\n\nAlso,  you  must provide function prototypes for all functions that take variable numbers\nof arguments (including \"printf\"); otherwise incorrect code is  generated  for  calls  to\nthose functions.\n\nIn  addition,  seriously  incorrect  code  results  if  you call a function with too many\narguments.  (Normally, extra arguments are harmlessly ignored.)\n\nThe \"rtd\" instruction is supported by the 68010, 68020, 68030,  68040,  68060  and  CPU32\nprocessors, but not by the 68000 or 5200.\n\nThe default is -mno-rtd.\n"
                },
                {
                    "name": "-malign-int",
                    "content": ""
                },
                {
                    "name": "-mno-align-int",
                    "content": "Control  whether  GCC  aligns  \"int\",  \"long\",  \"long long\", \"float\", \"double\", and \"long\ndouble\"  variables  on  a  32-bit   boundary   (-malign-int)   or   a   16-bit   boundary\n(-mno-align-int).   Aligning  variables  on  32-bit  boundaries  produces  code that runs\nsomewhat faster on processors with 32-bit busses at the expense of more memory.\n\nWarning: if you use the -malign-int switch, GCC aligns structures  containing  the  above\ntypes differently than most published application binary interface specifications for the\nm68k.\n\nUse  the  pc-relative  addressing  mode  of the 68000 directly, instead of using a global\noffset table.  At present, this option implies -fpic, allowing at most  a  16-bit  offset\nfor  pc-relative  addressing.  -fPIC is not presently supported with -mpcrel, though this\ncould be supported for 68020 and higher processors.\n"
                },
                {
                    "name": "-mno-strict-align",
                    "content": ""
                },
                {
                    "name": "-mstrict-align",
                    "content": "Do not (do) assume that unaligned memory references are handled by the system.\n"
                },
                {
                    "name": "-msep-data",
                    "content": "Generate code that allows the data segment to be located in a different  area  of  memory\nfrom  the  text  segment.   This  allows  for  execute-in-place in an environment without\nvirtual memory management.  This option implies -fPIC.\n"
                },
                {
                    "name": "-mno-sep-data",
                    "content": "Generate code that assumes that the data segment follows the text segment.  This  is  the\ndefault.\n"
                },
                {
                    "name": "-mid-shared-library",
                    "content": "Generate  code that supports shared libraries via the library ID method.  This allows for\nexecute-in-place  and  shared  libraries  in  an  environment  without   virtual   memory\nmanagement.  This option implies -fPIC.\n"
                },
                {
                    "name": "-mno-id-shared-library",
                    "content": "Generate  code that doesn't assume ID-based shared libraries are being used.  This is the\ndefault.\n"
                },
                {
                    "name": "-mshared-library-id=n",
                    "content": "Specifies the identification number  of  the  ID-based  shared  library  being  compiled.\nSpecifying  a  value of 0 generates more compact code; specifying other values forces the\nallocation of that number to the current library, but is no more space- or time-efficient\nthan omitting this option.\n"
                },
                {
                    "name": "-mxgot",
                    "content": ""
                },
                {
                    "name": "-mno-xgot",
                    "content": "When generating position-independent code for ColdFire, generate code that works  if  the\nGOT  has  more  than  8192  entries.   This code is larger and slower than code generated\nwithout this option.  On M680x0 processors, this option is not needed; -fPIC suffices.\n\nGCC normally uses a single instruction to load  values  from  the  GOT.   While  this  is\nrelatively  efficient,  it  only  works  if  the GOT is smaller than about 64k.  Anything\nlarger causes the linker to report an error such as:\n\nrelocation truncated to fit: R68KGOT16O foobar\n\nIf this happens, you should recompile your code with -mxgot.  It should  then  work  with\nvery large GOTs.  However, code generated with -mxgot is less efficient, since it takes 4\ninstructions to fetch the value of a global symbol.\n\nNote  that  some linkers, including newer versions of the GNU linker, can create multiple\nGOTs and sort GOT entries.  If you have such a linker, you should only need to use -mxgot\nwhen compiling a single object file that accesses more than 8192 GOT entries.   Very  few\ndo.\n\nThese options have no effect unless GCC is generating position-independent code.\n"
                },
                {
                    "name": "-mlong-jump-table-offsets",
                    "content": "Use 32-bit offsets in \"switch\" tables.  The default is to use 16-bit offsets.\n\nMCore Options\n\nThese are the -m options defined for the Motorola M*Core processors.\n"
                },
                {
                    "name": "-mhardlit",
                    "content": ""
                },
                {
                    "name": "-mno-hardlit",
                    "content": "Inline constants into the code stream if it can be done in two instructions or less.\n"
                },
                {
                    "name": "-mdiv",
                    "content": ""
                },
                {
                    "name": "-mno-div",
                    "content": "Use the divide instruction.  (Enabled by default).\n"
                },
                {
                    "name": "-mrelax-immediate",
                    "content": ""
                },
                {
                    "name": "-mno-relax-immediate",
                    "content": "Allow arbitrary-sized immediates in bit operations.\n"
                },
                {
                    "name": "-mwide-bitfields",
                    "content": ""
                },
                {
                    "name": "-mno-wide-bitfields",
                    "content": "Always treat bit-fields as \"int\"-sized.\n"
                },
                {
                    "name": "-m4byte-functions",
                    "content": ""
                },
                {
                    "name": "-mno-4byte-functions",
                    "content": "Force all functions to be aligned to a 4-byte boundary.\n"
                },
                {
                    "name": "-mcallgraph-data",
                    "content": ""
                },
                {
                    "name": "-mno-callgraph-data",
                    "content": "Emit callgraph information.\n"
                },
                {
                    "name": "-mslow-bytes",
                    "content": ""
                },
                {
                    "name": "-mno-slow-bytes",
                    "content": "Prefer word access when reading byte quantities.\n"
                },
                {
                    "name": "-mlittle-endian",
                    "content": ""
                },
                {
                    "name": "-mbig-endian",
                    "content": "Generate code for a little-endian target.\n"
                },
                {
                    "name": "-m210",
                    "content": ""
                },
                {
                    "name": "-m340",
                    "content": "Generate code for the 210 processor.\n"
                },
                {
                    "name": "-mno-lsim",
                    "content": "Assume  that  runtime  support  has  been  provided  and  so  omit  the simulator library\n(libsim.a) from the linker command line.\n"
                },
                {
                    "name": "-mstack-increment=_",
                    "content": "Set the maximum amount for a single stack increment operation.  Large values can increase\nthe speed of programs that contain functions that need a large amount of stack space, but\nthey can also trigger a segmentation fault if  the  stack  is  extended  too  much.   The\ndefault value is 0x1000.\n\nMicroBlaze Options\n"
                },
                {
                    "name": "-msoft-float",
                    "content": "Use software emulation for floating point (default).\n"
                },
                {
                    "name": "-mhard-float",
                    "content": "Use hardware floating-point instructions.\n"
                },
                {
                    "name": "-mmemcpy",
                    "content": "Do not optimize block moves, use \"memcpy\".\n"
                },
                {
                    "name": "-mno-clearbss",
                    "content": "This option is deprecated.  Use -fno-zero-initialized-in-bss instead.\n"
                },
                {
                    "name": "-mcpu=_",
                    "content": "Use  features  of,  and  schedule  code  for, the given CPU.  Supported values are in the\nformat vX.YY.Z, where X  is  a  major  version,  YY  is  the  minor  version,  and  Z  is\ncompatibility code.  Example values are v3.00.a, v4.00.b, v5.00.a, v5.00.b, v6.00.a.\n"
                },
                {
                    "name": "-mxl-soft-mul",
                    "content": "Use software multiply emulation (default).\n"
                },
                {
                    "name": "-mxl-soft-div",
                    "content": "Use software emulation for divides (default).\n"
                },
                {
                    "name": "-mxl-barrel-shift",
                    "content": "Use the hardware barrel shifter.\n"
                },
                {
                    "name": "-mxl-pattern-compare",
                    "content": "Use pattern compare instructions.\n"
                },
                {
                    "name": "-msmall-divides",
                    "content": "Use table lookup optimization for small signed integer divisions.\n"
                },
                {
                    "name": "-mxl-stack-check",
                    "content": "This option is deprecated.  Use -fstack-check instead.\n"
                },
                {
                    "name": "-mxl-gp-opt",
                    "content": "Use GP-relative \".sdata\"/\".sbss\" sections.\n"
                },
                {
                    "name": "-mxl-multiply-high",
                    "content": "Use multiply high instructions for high part of 32x32 multiply.\n"
                },
                {
                    "name": "-mxl-float-convert",
                    "content": "Use hardware floating-point conversion instructions.\n"
                },
                {
                    "name": "-mxl-float-sqrt",
                    "content": "Use hardware floating-point square root instruction.\n"
                },
                {
                    "name": "-mbig-endian",
                    "content": "Generate code for a big-endian target.\n"
                },
                {
                    "name": "-mlittle-endian",
                    "content": "Generate code for a little-endian target.\n"
                },
                {
                    "name": "-mxl-reorder",
                    "content": "Use reorder instructions (swap and byte reversed load/store).\n"
                },
                {
                    "name": "-mxl-mode-_",
                    "content": "Select application model app-model.  Valid models are\n\nexecutable\nnormal executable (default), uses startup code crt0.o.\n\nxmdstub\nfor  use  with  Xilinx  Microprocessor  Debugger (XMD) based software intrusive debug\nagent called xmdstub. This uses startup file crt1.o and sets the start address of the\nprogram to 0x800.\n\nbootstrap\nfor applications that are loaded using a bootloader.  This model  uses  startup  file\ncrt2.o  which does not contain a processor reset vector handler. This is suitable for\ntransferring control  on  a  processor  reset  to  the  bootloader  rather  than  the\napplication.\n\nnovectors\nfor  applications  that do not require any of the MicroBlaze vectors. This option may\nbe useful for applications running within a monitoring application. This  model  uses\ncrt3.o as a startup file.\n\nOption -xl-mode-app-model is a deprecated alias for -mxl-mode-app-model.\n"
                },
                {
                    "name": "-mpic-data-is-text-relative",
                    "content": "Assume  that  the displacement between the text and data segments is fixed at static link\ntime.  This allows data to be referenced by offset from start of text address instead  of\nGOT since PC-relative addressing is not supported.\n\nMIPS Options\n"
                },
                {
                    "name": "-EB",
                    "content": ""
                },
                {
                    "name": "-EL",
                    "content": ""
                },
                {
                    "name": "-march=_",
                    "content": "Generate code that runs on arch, which can be the name of a generic MIPS ISA, or the name\nof  a  particular  processor.   The  ISA  names  are: mips1, mips2, mips3, mips4, mips32,\nmips32r2,  mips32r3,  mips32r5,  mips32r6,  mips64,  mips64r2,  mips64r3,  mips64r5   and\nmips64r6.   The  processor  names  are: 4kc, 4km, 4kp, 4ksc, 4kec, 4kem, 4kep, 4ksd, 5kc,\n5kf, 20kc, 24kc, 24kf21, 24kf11, 24kec, 24kef21,  24kef11,  34kc,  34kf21,  34kf11,\n34kn,  74kc,  74kf21,  74kf11,  74kf32,  1004kc,  1004kf21,  1004kf11, i6400, i6500,\ninteraptiv, loongson2e, loongson2f, loongson3a, gs464, gs464e, gs264e, m4k, m14k,  m14kc,\nm14ke,  m14kec,  m5100,  m5101,  octeon,  octeon+, octeon2, octeon3, orion, p5600, p6600,\nr2000, r3000, r3900, r4000, r4400, r4600, r4650,  r4700,  r5900,  r6000,  r8000,  rm7000,\nrm9000,  r10000,  r12000,  r14000,  r16000, sb1, sr71000, vr4100, vr4111, vr4120, vr4130,\nvr4300, vr5000, vr5400, vr5500, xlr and xlp.  The special value from-abi selects the most\ncompatible architecture for the selected ABI (that is, mips1 for 32-bit  ABIs  and  mips3\nfor 64-bit ABIs).\n\nThe  native  Linux/GNU  toolchain  also supports the value native, which selects the best\narchitecture option for the host processor.  -march=native has no effect if GCC does  not\nrecognize the processor.\n\nIn  processor  names,  a  final  000  can  be abbreviated as k (for example, -march=r2k).\nPrefixes are optional, and vr may be written r.\n\nNames of the form nf21 refer to processors with FPUs clocked at half  the  rate  of  the\ncore,  names  of the form nf11 refer to processors with FPUs clocked at the same rate as\nthe core, and names of the form nf32 refer to processors with FPUs clocked  a  ratio  of\n3:2 with respect to the core.  For compatibility reasons, nf is accepted as a synonym for\nnf21 while nx and bfx are accepted as synonyms for nf11.\n\nGCC  defines  two  macros  based on the value of this option.  The first is \"MIPSARCH\",\nwhich gives the name of target architecture, as  a  string.   The  second  has  the  form\n\"MIPSARCHfoo\",  where  foo  is  the  capitalized  value of \"MIPSARCH\".  For example,\n-march=r2000 sets \"MIPSARCH\" to \"r2000\" and defines the macro \"MIPSARCHR2000\".\n\nNote that the \"MIPSARCH\" macro uses the processor names given above.  In  other  words,\nit  has  the  full prefix and does not abbreviate 000 as k.  In the case of from-abi, the\nmacro names the resolved architecture (either \"mips1\" or \"mips3\").  It names the  default\narchitecture when no -march option is given.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "Optimize  for  arch.   Among  other things, this option controls the way instructions are\nscheduled, and the perceived cost of arithmetic operations.  The list of arch  values  is\nthe same as for -march.\n\nWhen  this  option  is not used, GCC optimizes for the processor specified by -march.  By\nusing -march and -mtune together, it is possible to generate code that runs on  a  family\nof processors, but optimize the code for one particular member of that family.\n\n-mtune  defines  the macros \"MIPSTUNE\" and \"MIPSTUNEfoo\", which work in the same way\nas the -march ones described above.\n"
                },
                {
                    "name": "-mips1",
                    "content": "Equivalent to -march=mips1.\n"
                },
                {
                    "name": "-mips2",
                    "content": "Equivalent to -march=mips2.\n"
                },
                {
                    "name": "-mips3",
                    "content": "Equivalent to -march=mips3.\n"
                },
                {
                    "name": "-mips4",
                    "content": "Equivalent to -march=mips4.\n"
                },
                {
                    "name": "-mips32",
                    "content": "Equivalent to -march=mips32.\n"
                },
                {
                    "name": "-mips32r3",
                    "content": "Equivalent to -march=mips32r3.\n"
                },
                {
                    "name": "-mips32r5",
                    "content": "Equivalent to -march=mips32r5.\n"
                },
                {
                    "name": "-mips32r6",
                    "content": "Equivalent to -march=mips32r6.\n"
                },
                {
                    "name": "-mips64",
                    "content": "Equivalent to -march=mips64.\n"
                },
                {
                    "name": "-mips64r2",
                    "content": "Equivalent to -march=mips64r2.\n"
                },
                {
                    "name": "-mips64r3",
                    "content": "Equivalent to -march=mips64r3.\n"
                },
                {
                    "name": "-mips64r5",
                    "content": "Equivalent to -march=mips64r5.\n"
                },
                {
                    "name": "-mips64r6",
                    "content": "Equivalent to -march=mips64r6.\n"
                },
                {
                    "name": "-mips16",
                    "content": ""
                },
                {
                    "name": "-mno-mips16",
                    "content": "Generate (do not generate)  MIPS16  code.   If  GCC  is  targeting  a  MIPS32  or  MIPS64\narchitecture, it makes use of the MIPS16e ASE.\n\nMIPS16  code  generation  can  also  be  controlled  on  a per-function basis by means of\n\"mips16\" and \"nomips16\" attributes.\n"
                },
                {
                    "name": "-mflip-mips16",
                    "content": "Generate MIPS16 code on alternating functions.  This option is  provided  for  regression\ntesting  of mixed MIPS16/non-MIPS16 code generation, and is not intended for ordinary use\nin compiling user code.\n"
                },
                {
                    "name": "-minterlink-compressed",
                    "content": ""
                },
                {
                    "name": "-mno-interlink-compressed",
                    "content": "Require (do not require) that code using the standard (uncompressed) MIPS  ISA  be  link-\ncompatible with MIPS16 and microMIPS code, and vice versa.\n\nFor  example,  code  using  the  standard  ISA encoding cannot jump directly to MIPS16 or\nmicroMIPS code; it must either use a call or an  indirect  jump.   -minterlink-compressed\ntherefore  disables  direct  jumps  unless  GCC  knows that the target of the jump is not\ncompressed.\n"
                },
                {
                    "name": "-minterlink-mips16",
                    "content": ""
                },
                {
                    "name": "-mno-interlink-mips16",
                    "content": "Aliases of -minterlink-compressed and -mno-interlink-compressed.  These  options  predate\nthe microMIPS ASE and are retained for backwards compatibility.\n"
                },
                {
                    "name": "-mabi=32",
                    "content": ""
                },
                {
                    "name": "-mabi=o64",
                    "content": ""
                },
                {
                    "name": "-mabi=n32",
                    "content": ""
                },
                {
                    "name": "-mabi=64",
                    "content": ""
                },
                {
                    "name": "-mabi=eabi",
                    "content": "Generate code for the given ABI.\n\nNote that the EABI has a 32-bit and a 64-bit variant.  GCC normally generates 64-bit code\nwhen you select a 64-bit architecture, but you can use -mgp32 to get 32-bit code instead.\n\nFor information about the O64 ABI, see <https://gcc.gnu.org/projects/mipso64-abi.html>.\n\nGCC  supports  a  variant  of the o32 ABI in which floating-point registers are 64 rather\nthan 32 bits wide.  You can select this  combination  with  -mabi=32  -mfp64.   This  ABI\nrelies  on  the  \"mthc1\"  and  \"mfhc1\"  instructions  and is therefore only supported for\nMIPS32R2, MIPS32R3 and MIPS32R5 processors.\n\nThe register assignments for arguments and return values remain the same, but each scalar\nvalue is passed in a single 64-bit register rather than a pair of 32-bit registers.   For\nexample,  scalar floating-point values are returned in $f0 only, not a $f0/$f1 pair.  The\nset of call-saved registers also remains the  same  in  that  the  even-numbered  double-\nprecision registers are saved.\n\nTwo  additional  variants of the o32 ABI are supported to enable a transition from 32-bit\nto 64-bit registers.  These are FPXX (-mfpxx) and  FP64A  (-mfp64  -mno-odd-spreg).   The\nFPXX  extension  mandates  that  all code must execute correctly when run using 32-bit or\n64-bit registers.  The code can be interlinked with either FP32 or FP64,  but  not  both.\nThe  FP64A extension is similar to the FP64 extension but forbids the use of odd-numbered\nsingle-precision registers.  This can be used in conjunction with the \"FRE\" mode of  FPUs\nin  MIPS32R5  processors  and allows both FP32 and FP64A code to interlink and run in the\nsame process without changing FPU modes.\n"
                },
                {
                    "name": "-mabicalls",
                    "content": ""
                },
                {
                    "name": "-mno-abicalls",
                    "content": "Generate (do not  generate)  code  that  is  suitable  for  SVR4-style  dynamic  objects.\n-mabicalls is the default for SVR4-based systems.\n"
                },
                {
                    "name": "-mshared",
                    "content": ""
                },
                {
                    "name": "-mno-shared",
                    "content": "Generate  (do  not  generate)  code  that  is  fully  position-independent,  and that can\ntherefore be linked into shared libraries.  This option only affects -mabicalls.\n\nAll -mabicalls code has traditionally been position-independent,  regardless  of  options\nlike  -fPIC and -fpic.  However, as an extension, the GNU toolchain allows executables to\nuse  absolute  accesses  for  locally-binding  symbols.   It  can  also  use  shorter  GP\ninitialization  sequences  and  generate direct calls to locally-defined functions.  This\nmode is selected by -mno-shared.\n\n-mno-shared depends on binutils 2.16 or higher and generates objects  that  can  only  be\nlinked  by  the  GNU  linker.   However,  the option does not affect the ABI of the final\nexecutable; it only affects the ABI of relocatable objects.  Using -mno-shared  generally\nmakes executables both smaller and quicker.\n\n-mshared is the default.\n"
                },
                {
                    "name": "-mplt",
                    "content": ""
                },
                {
                    "name": "-mno-plt",
                    "content": "Assume  (do  not  assume)  that  the  static  and  dynamic  linkers support PLTs and copy\nrelocations.  This option only affects -mno-shared -mabicalls.  For  the  n64  ABI,  this\noption has no effect without -msym32.\n\nYou  can  make -mplt the default by configuring GCC with --with-mips-plt.  The default is\n-mno-plt otherwise.\n"
                },
                {
                    "name": "-mxgot",
                    "content": ""
                },
                {
                    "name": "-mno-xgot",
                    "content": "Lift (do not lift) the usual restrictions on the size of the global offset table.\n\nGCC normally uses a single instruction to load  values  from  the  GOT.   While  this  is\nrelatively  efficient,  it  only  works  if  the GOT is smaller than about 64k.  Anything\nlarger causes the linker to report an error such as:\n\nrelocation truncated to fit: RMIPSGOT16 foobar\n\nIf this happens, you should recompile your code with -mxgot.  This works with very  large\nGOTs,  although  the  code  is  also less efficient, since it takes three instructions to\nfetch the value of a global symbol.\n\nNote that some linkers can create multiple GOTs.  If you have such a linker,  you  should\nonly  need  to use -mxgot when a single object file accesses more than 64k's worth of GOT\nentries.  Very few do.\n\nThese options have no effect unless GCC is generating position independent code.\n"
                },
                {
                    "name": "-mgp32",
                    "content": "Assume that general-purpose registers are 32 bits wide.\n"
                },
                {
                    "name": "-mgp64",
                    "content": "Assume that general-purpose registers are 64 bits wide.\n"
                },
                {
                    "name": "-mfp32",
                    "content": "Assume that floating-point registers are 32 bits wide.\n"
                },
                {
                    "name": "-mfp64",
                    "content": "Assume that floating-point registers are 64 bits wide.\n"
                },
                {
                    "name": "-mfpxx",
                    "content": "Do not assume the width of floating-point registers.\n"
                },
                {
                    "name": "-mhard-float",
                    "content": "Use floating-point coprocessor instructions.\n"
                },
                {
                    "name": "-msoft-float",
                    "content": "Do  not  use   floating-point   coprocessor   instructions.    Implement   floating-point\ncalculations using library calls instead.\n"
                },
                {
                    "name": "-mno-float",
                    "content": "Equivalent to -msoft-float, but additionally asserts that the program being compiled does\nnot  perform  any  floating-point operations.  This option is presently supported only by\nsome bare-metal MIPS configurations, where it may select a special set of libraries  that\nlack  all  floating-point  support  (including,  for example, the floating-point \"printf\"\nformats).   If  code  compiled  with  -mno-float  accidentally  contains   floating-point\noperations, it is likely to suffer a link-time or run-time failure.\n"
                },
                {
                    "name": "-msingle-float",
                    "content": "Assume that the floating-point coprocessor only supports single-precision operations.\n"
                },
                {
                    "name": "-mdouble-float",
                    "content": "Assume that the floating-point coprocessor supports double-precision operations.  This is\nthe default.\n"
                },
                {
                    "name": "-modd-spreg",
                    "content": ""
                },
                {
                    "name": "-mno-odd-spreg",
                    "content": "Enable the use of odd-numbered single-precision floating-point registers for the o32 ABI.\nThis is the default for processors that are known to support these registers.  When using\nthe o32 FPXX ABI, -mno-odd-spreg is set by default.\n"
                },
                {
                    "name": "-mabs=2008",
                    "content": ""
                },
                {
                    "name": "-mabs=legacy",
                    "content": "These  options control the treatment of the special not-a-number (NaN) IEEE 754 floating-\npoint data with the \"abs.fmt\" and \"neg.fmt\" machine instructions.\n\nBy default or when -mabs=legacy is used the legacy treatment is selected.  In  this  case\nthese  instructions  are  considered  arithmetic  and  avoided where correct operation is\nrequired and the input operand might be a NaN.  A longer sequence  of  instructions  that\nmanipulate  the  sign  bit  of  floating-point  datum manually is used instead unless the\n-ffinite-math-only option has also been specified.\n\nThe  -mabs=2008  option  selects  the  IEEE  754-2008  treatment.   In  this  case  these\ninstructions  are  considered  non-arithmetic  and  therefore  operating correctly in all\ncases, including in particular where the input operand is a NaN.  These instructions  are\ntherefore always used for the respective operations.\n"
                },
                {
                    "name": "-mnan=2008",
                    "content": ""
                },
                {
                    "name": "-mnan=legacy",
                    "content": "These  options  control the encoding of the special not-a-number (NaN) IEEE 754 floating-\npoint data.\n\nThe -mnan=legacy option selects the legacy encoding.  In this case quiet NaNs (qNaNs) are\ndenoted by the first bit of their trailing significand field being 0,  whereas  signaling\nNaNs (sNaNs) are denoted by the first bit of their trailing significand field being 1.\n\nThe -mnan=2008 option selects the IEEE 754-2008 encoding.  In this case qNaNs are denoted\nby  the  first bit of their trailing significand field being 1, whereas sNaNs are denoted\nby the first bit of their trailing significand field being 0.\n\nThe default is -mnan=legacy unless GCC has been configured with --with-nan=2008.\n"
                },
                {
                    "name": "-mllsc",
                    "content": ""
                },
                {
                    "name": "-mno-llsc",
                    "content": "Use (do not use) ll, sc, and  sync  instructions  to  implement  atomic  memory  built-in\nfunctions.   When  neither  option  is specified, GCC uses the instructions if the target\narchitecture supports them.\n\n-mllsc is useful if the runtime environment can emulate the  instructions  and  -mno-llsc\ncan  be  useful  when  compiling  for  nonstandard  ISAs.  You can make either option the\ndefault by configuring GCC with --with-llsc and --without-llsc respectively.  --with-llsc\nis the default for some configurations; see the installation documentation for details.\n"
                },
                {
                    "name": "-mdsp",
                    "content": ""
                },
                {
                    "name": "-mno-dsp",
                    "content": "Use (do not use) revision 1 of the MIPS DSP ASE.\nThis  option  defines  the  preprocessor   macro   \"mipsdsp\".    It   also   defines\n\"mipsdsprev\" to 1.\n"
                },
                {
                    "name": "-mdspr2",
                    "content": ""
                },
                {
                    "name": "-mno-dspr2",
                    "content": "Use (do not use) revision 2 of the MIPS DSP ASE.\nThis  option  defines the preprocessor macros \"mipsdsp\" and \"mipsdspr2\".  It also\ndefines \"mipsdsprev\" to 2.\n"
                },
                {
                    "name": "-msmartmips",
                    "content": ""
                },
                {
                    "name": "-mno-smartmips",
                    "content": "Use (do not use) the MIPS SmartMIPS ASE.\n"
                },
                {
                    "name": "-mpaired-single",
                    "content": ""
                },
                {
                    "name": "-mno-paired-single",
                    "content": "Use (do not use) paired-single floating-point instructions.\nThis option requires hardware floating-point support to be enabled.\n"
                },
                {
                    "name": "-mdmx",
                    "content": ""
                },
                {
                    "name": "-mno-mdmx",
                    "content": "Use (do not use) MIPS Digital Media Extension instructions.  This option can only be used\nwhen generating 64-bit code and requires hardware floating-point support to be enabled.\n"
                },
                {
                    "name": "-mips3d",
                    "content": ""
                },
                {
                    "name": "-mno-mips3d",
                    "content": "Use (do not use) the MIPS-3D ASE.  The option -mips3d implies -mpaired-single.\n"
                },
                {
                    "name": "-mmicromips",
                    "content": ""
                },
                {
                    "name": "-mno-micromips",
                    "content": "Generate (do not generate) microMIPS code.\n\nMicroMIPS code generation can also be controlled on a  per-function  basis  by  means  of\n\"micromips\" and \"nomicromips\" attributes.\n"
                },
                {
                    "name": "-mmt",
                    "content": ""
                },
                {
                    "name": "-mno-mt",
                    "content": "Use (do not use) MT Multithreading instructions.\n"
                },
                {
                    "name": "-mmcu",
                    "content": ""
                },
                {
                    "name": "-mno-mcu",
                    "content": "Use (do not use) the MIPS MCU ASE instructions.\n"
                },
                {
                    "name": "-meva",
                    "content": ""
                },
                {
                    "name": "-mno-eva",
                    "content": "Use (do not use) the MIPS Enhanced Virtual Addressing instructions.\n"
                },
                {
                    "name": "-mvirt",
                    "content": ""
                },
                {
                    "name": "-mno-virt",
                    "content": "Use (do not use) the MIPS Virtualization (VZ) instructions.\n"
                },
                {
                    "name": "-mxpa",
                    "content": ""
                },
                {
                    "name": "-mno-xpa",
                    "content": "Use (do not use) the MIPS eXtended Physical Address (XPA) instructions.\n"
                },
                {
                    "name": "-mcrc",
                    "content": ""
                },
                {
                    "name": "-mno-crc",
                    "content": "Use (do not use) the MIPS Cyclic Redundancy Check (CRC) instructions.\n"
                },
                {
                    "name": "-mginv",
                    "content": ""
                },
                {
                    "name": "-mno-ginv",
                    "content": "Use (do not use) the MIPS Global INValidate (GINV) instructions.\n"
                },
                {
                    "name": "-mloongson-mmi",
                    "content": ""
                },
                {
                    "name": "-mno-loongson-mmi",
                    "content": "Use (do not use) the MIPS Loongson MultiMedia extensions Instructions (MMI).\n"
                },
                {
                    "name": "-mloongson-ext",
                    "content": ""
                },
                {
                    "name": "-mno-loongson-ext",
                    "content": "Use (do not use) the MIPS Loongson EXTensions (EXT) instructions.\n"
                },
                {
                    "name": "-mloongson-ext2",
                    "content": ""
                },
                {
                    "name": "-mno-loongson-ext2",
                    "content": "Use (do not use) the MIPS Loongson EXTensions r2 (EXT2) instructions.\n"
                },
                {
                    "name": "-mlong64",
                    "content": "Force  \"long\"  types  to be 64 bits wide.  See -mlong32 for an explanation of the default\nand the way that the pointer size is determined.\n"
                },
                {
                    "name": "-mlong32",
                    "content": "Force \"long\", \"int\", and pointer types to be 32 bits wide.\n\nThe default size of \"int\"s, \"long\"s and pointers depends on the ABI.  All  the  supported\nABIs  use  32-bit  \"int\"s.  The n64 ABI uses 64-bit \"long\"s, as does the 64-bit EABI; the\nothers use 32-bit \"long\"s.  Pointers are the same size as \"long\"s, or the  same  size  as\ninteger registers, whichever is smaller.\n"
                },
                {
                    "name": "-msym32",
                    "content": ""
                },
                {
                    "name": "-mno-sym32",
                    "content": "Assume  (do  not  assume) that all symbols have 32-bit values, regardless of the selected\nABI.  This option is useful in combination with -mabi=64  and  -mno-abicalls  because  it\nallows GCC to generate shorter and faster references to symbolic addresses.\n"
                },
                {
                    "name": "-G _",
                    "content": "Put  definitions  of  externally-visible  data in a small data section if that data is no\nbigger than num bytes.  GCC can then generate more efficient accesses to  the  data;  see\n-mgpopt for details.\n\nThe default -G option depends on the configuration.\n",
                    "flag": "-G"
                },
                {
                    "name": "-mlocal-sdata",
                    "content": ""
                },
                {
                    "name": "-mno-local-sdata",
                    "content": "Extend  (do not extend) the -G behavior to local data too, such as to static variables in\nC.  -mlocal-sdata is the default for all configurations.\n\nIf the linker complains that an application is using too much small data, you might  want\nto  try  rebuilding the less performance-critical parts with -mno-local-sdata.  You might\nalso want to build large libraries with -mno-local-sdata, so  that  the  libraries  leave\nmore room for the main program.\n"
                },
                {
                    "name": "-mextern-sdata",
                    "content": ""
                },
                {
                    "name": "-mno-extern-sdata",
                    "content": "Assume  (do  not  assume)  that externally-defined data is in a small data section if the\nsize of that data is within  the  -G  limit.   -mextern-sdata  is  the  default  for  all\nconfigurations.\n\nIf  you  compile  a  module  Mod with -mextern-sdata -G num -mgpopt, and Mod references a\nvariable Var that is no bigger than num bytes, you must make sure that Var is placed in a\nsmall data section.  If Var is defined by another module, you must  either  compile  that\nmodule with a high-enough -G setting or attach a \"section\" attribute to Var's definition.\nIf Var is common, you must link the application with a high-enough -G setting.\n\nThe easiest way of satisfying these restrictions is to compile and link every module with\nthe  same  -G  option.   However,  you  may wish to build a library that supports several\ndifferent small data limits.  You can do this by compiling the library with  the  highest\nsupported  -G  setting  and additionally using -mno-extern-sdata to stop the library from\nmaking assumptions about externally-defined data.\n"
                },
                {
                    "name": "-mgpopt",
                    "content": ""
                },
                {
                    "name": "-mno-gpopt",
                    "content": "Use (do not use) GP-relative accesses for symbols that are known to be in  a  small  data\nsection;  see  -G,  -mlocal-sdata  and  -mextern-sdata.   -mgpopt  is the default for all\nconfigurations.\n\n-mno-gpopt is useful for cases where the $gp register might not hold the value of  \"gp\".\nFor  example,  if  the  code  is  part of a library that might be used in a boot monitor,\nprograms that call boot monitor  routines  pass  an  unknown  value  in  $gp.   (In  such\nsituations, the boot monitor itself is usually compiled with -G0.)\n\n-mno-gpopt implies -mno-local-sdata and -mno-extern-sdata.\n"
                },
                {
                    "name": "-membedded-data",
                    "content": ""
                },
                {
                    "name": "-mno-embedded-data",
                    "content": "Allocate  variables  to  the  read-only  data section first if possible, then next in the\nsmall data section if possible, otherwise in data.  This gives slightly slower code  than\nthe  default,  but  reduces  the  amount  of RAM required when executing, and thus may be\npreferred for some embedded systems.\n"
                },
                {
                    "name": "-muninit-const-in-rodata",
                    "content": ""
                },
                {
                    "name": "-mno-uninit-const-in-rodata",
                    "content": "Put uninitialized \"const\" variables in the read-only data section.  This option  is  only\nmeaningful in conjunction with -membedded-data.\n"
                },
                {
                    "name": "-mcode-readable=_",
                    "content": "Specify  whether  GCC  may  generate code that reads from executable sections.  There are\nthree possible settings:\n\n-mcode-readable=yes\nInstructions may freely access executable sections.  This is the default setting.\n\n-mcode-readable=pcrel\nMIPS16 PC-relative load  instructions  can  access  executable  sections,  but  other\ninstructions  must not do so.  This option is useful on 4KSc and 4KSd processors when\nthe code TLBs have the Read Inhibit bit set.  It is also useful  on  processors  that\ncan  be  configured to have a dual instruction/data SRAM interface and that, like the\nM4K, automatically redirect PC-relative loads to the instruction RAM.\n\n-mcode-readable=no\nInstructions must not access executable sections.   This  option  can  be  useful  on\ntargets  that  are configured to have a dual instruction/data SRAM interface but that\n(unlike the M4K) do not automatically redirect PC-relative loads to  the  instruction\nRAM.\n"
                },
                {
                    "name": "-msplit-addresses",
                    "content": ""
                },
                {
                    "name": "-mno-split-addresses",
                    "content": "Enable  (disable) use of the %hi() and %lo() assembler relocation operators.  This option\nhas been superseded by -mexplicit-relocs but is retained for backwards compatibility.\n"
                },
                {
                    "name": "-mexplicit-relocs",
                    "content": ""
                },
                {
                    "name": "-mno-explicit-relocs",
                    "content": "Use (do not use) assembler relocation operators when  dealing  with  symbolic  addresses.\nThe alternative, selected by -mno-explicit-relocs, is to use assembler macros instead.\n\n-mexplicit-relocs  is the default if GCC was configured to use an assembler that supports\nrelocation operators.\n"
                },
                {
                    "name": "-mcheck-zero-division",
                    "content": ""
                },
                {
                    "name": "-mno-check-zero-division",
                    "content": "Trap (do not trap) on integer division by zero.\n\nThe default is -mcheck-zero-division.\n"
                },
                {
                    "name": "-mdivide-traps",
                    "content": ""
                },
                {
                    "name": "-mdivide-breaks",
                    "content": "MIPS systems check for division by zero by generating either  a  conditional  trap  or  a\nbreak instruction.  Using traps results in smaller code, but is only supported on MIPS II\nand  later.   Also,  some versions of the Linux kernel have a bug that prevents trap from\ngenerating the proper signal (\"SIGFPE\").  Use -mdivide-traps to allow  conditional  traps\non architectures that support them and -mdivide-breaks to force the use of breaks.\n\nThe default is usually -mdivide-traps, but this can be overridden at configure time using\n--with-divide=breaks.    Divide-by-zero   checks   can   be   completely  disabled  using\n-mno-check-zero-division.\n"
                },
                {
                    "name": "-mload-store-pairs",
                    "content": ""
                },
                {
                    "name": "-mno-load-store-pairs",
                    "content": "Enable (disable) an optimization that pairs consecutive load  or  store  instructions  to\nenable  load/store bonding.  This option is enabled by default but only takes effect when\nthe selected architecture is known to support bonding.\n"
                },
                {
                    "name": "-munaligned-access",
                    "content": ""
                },
                {
                    "name": "-mno-unaligned-access",
                    "content": "Enable (disable) direct unaligned access for MIPS Release 6.  MIPSr6 requires  load/store\nunaligned-access  support,  by hardware or trap&emulate.  So -mno-unaligned-access may be\nneeded by kernel.\n"
                },
                {
                    "name": "-mmemcpy",
                    "content": ""
                },
                {
                    "name": "-mno-memcpy",
                    "content": "Force (do not force) the use of \"memcpy\" for non-trivial block  moves.   The  default  is\n-mno-memcpy, which allows GCC to inline most constant-sized copies.\n"
                },
                {
                    "name": "-mlong-calls",
                    "content": ""
                },
                {
                    "name": "-mno-long-calls",
                    "content": "Disable  (do not disable) use of the \"jal\" instruction.  Calling functions using \"jal\" is\nmore efficient but requires the caller and callee to be in the same 256 megabyte segment.\n\nThis option has no effect on abicalls code.  The default is -mno-long-calls.\n"
                },
                {
                    "name": "-mmad",
                    "content": ""
                },
                {
                    "name": "-mno-mad",
                    "content": "Enable (disable) use of the \"mad\", \"madu\" and \"mul\"  instructions,  as  provided  by  the\nR4650 ISA.\n"
                },
                {
                    "name": "-mimadd",
                    "content": ""
                },
                {
                    "name": "-mno-imadd",
                    "content": "Enable  (disable)  use  of  the  \"madd\"  and \"msub\" integer instructions.  The default is\n-mimadd on architectures that support \"madd\" and \"msub\" except for the  74k  architecture\nwhere it was found to generate slower code.\n"
                },
                {
                    "name": "-mfused-madd",
                    "content": ""
                },
                {
                    "name": "-mno-fused-madd",
                    "content": "Enable  (disable)  use  of the floating-point multiply-accumulate instructions, when they\nare available.  The default is -mfused-madd.\n\nOn the R8000 CPU when multiply-accumulate instructions are used, the intermediate product\nis calculated to infinite precision and is not subject to the FCSR  Flush  to  Zero  bit.\nThis  may  be  undesirable  in  some  circumstances.   On  other processors the result is\nnumerically identical  to  the  equivalent  computation  using  separate  multiply,  add,\nsubtract and negate instructions.\n"
                },
                {
                    "name": "-nocpp",
                    "content": "Tell  the MIPS assembler to not run its preprocessor over user assembler files (with a .s\nsuffix) when assembling them.\n"
                },
                {
                    "name": "-mfix-24k",
                    "content": ""
                },
                {
                    "name": "-mno-fix-24k",
                    "content": "Work around the 24K E48 (lost data on stores during refill) errata.  The workarounds  are\nimplemented by the assembler rather than by GCC.\n"
                },
                {
                    "name": "-mfix-r4000",
                    "content": ""
                },
                {
                    "name": "-mno-fix-r4000",
                    "content": "Work around certain R4000 CPU errata:\n\n-   A  double-word  or  a  variable  shift  may  give  an  incorrect  result  if executed\nimmediately after starting an integer division.\n\n-   A double-word or a variable shift may give an incorrect result if executed  while  an\ninteger multiplication is in progress.\n\n-   An  integer  division  may  give  an incorrect result if started in a delay slot of a\ntaken branch or a jump.\n"
                },
                {
                    "name": "-mfix-r4400",
                    "content": ""
                },
                {
                    "name": "-mno-fix-r4400",
                    "content": "Work around certain R4400 CPU errata:\n\n-   A double-word  or  a  variable  shift  may  give  an  incorrect  result  if  executed\nimmediately after starting an integer division.\n"
                },
                {
                    "name": "-mfix-r10000",
                    "content": ""
                },
                {
                    "name": "-mno-fix-r10000",
                    "content": "Work around certain R10000 errata:\n\n-   \"ll\"/\"sc\"  sequences  may  not behave atomically on revisions prior to 3.0.  They may\ndeadlock on revisions 2.6 and earlier.\n\nThis  option  can  only  be  used  if  the  target  architecture  supports  branch-likely\ninstructions.  -mfix-r10000 is the default when -march=r10000 is used; -mno-fix-r10000 is\nthe default otherwise.\n"
                },
                {
                    "name": "-mfix-r5900",
                    "content": ""
                },
                {
                    "name": "-mno-fix-r5900",
                    "content": "Do  not  attempt  to  schedule  the preceding instruction into the delay slot of a branch\ninstruction placed at the end of a short loop of six instructions  or  fewer  and  always\nschedule  a \"nop\" instruction there instead.  The short loop bug under certain conditions\ncauses loops to execute only once or twice, due to a hardware bug in the R5900 chip.  The\nworkaround is implemented by the assembler rather than by GCC.\n"
                },
                {
                    "name": "-mfix-rm7000",
                    "content": ""
                },
                {
                    "name": "-mno-fix-rm7000",
                    "content": "Work around the RM7000 \"dmult\"/\"dmultu\" errata.  The workarounds are implemented  by  the\nassembler rather than by GCC.\n"
                },
                {
                    "name": "-mfix-vr4120",
                    "content": ""
                },
                {
                    "name": "-mno-fix-vr4120",
                    "content": "Work around certain VR4120 errata:\n\n-   \"dmultu\" does not always produce the correct result.\n\n-   \"div\"  and  \"ddiv\" do not always produce the correct result if one of the operands is\nnegative.\n\nThe workarounds for the division errata  rely  on  special  functions  in  libgcc.a.   At\npresent, these functions are only provided by the \"mips64vr*-elf\" configurations.\n\nOther  VR4120  errata require a NOP to be inserted between certain pairs of instructions.\nThese errata are handled by the assembler, not by GCC itself.\n"
                },
                {
                    "name": "-mfix-vr4130",
                    "content": "Work around the VR4130 \"mflo\"/\"mfhi\" errata.  The  workarounds  are  implemented  by  the\nassembler  rather  than by GCC, although GCC avoids using \"mflo\" and \"mfhi\" if the VR4130\n\"macc\", \"macchi\", \"dmacc\" and \"dmacchi\" instructions are available instead.\n"
                },
                {
                    "name": "-mfix-sb1",
                    "content": ""
                },
                {
                    "name": "-mno-fix-sb1",
                    "content": "Work around certain SB-1 CPU core errata.  (This flag currently  works  around  the  SB-1\nrevision 2 \"F1\" and \"F2\" floating-point errata.)\n"
                },
                {
                    "name": "-mr10k-cache-barrier=_",
                    "content": "Specify whether GCC should insert cache barriers to avoid the side effects of speculation\non R10K processors.\n\nIn  common  with  many processors, the R10K tries to predict the outcome of a conditional\nbranch and speculatively executes instructions from the \"taken\" branch.  It later  aborts\nthese instructions if the predicted outcome is wrong.  However, on the R10K, even aborted\ninstructions can have side effects.\n\nThis  problem  only affects kernel stores and, depending on the system, kernel loads.  As\nan example, a speculatively-executed store may load the target memory into cache and mark\nthe cache line as dirty, even if the store itself is later aborted.  If a  DMA  operation\nwrites  to  the  same  area of memory before the \"dirty\" line is flushed, the cached data\noverwrites the DMA-ed data.  See the  R10K  processor  manual  for  a  full  description,\nincluding other potential problems.\n\nOne  workaround  is  to insert cache barrier instructions before every memory access that\nmight be speculatively executed and  that  might  have  side  effects  even  if  aborted.\n-mr10k-cache-barrier=setting  controls  GCC's  implementation  of  this  workaround.   It\nassumes that aborted accesses to any byte in the following regions  does  not  have  side\neffects:\n\n1.  the memory occupied by the current function's stack frame;\n\n2.  the memory occupied by an incoming stack argument;\n\n3.  the memory occupied by an object with a link-time-constant address.\n\nIt  is  the  kernel's responsibility to ensure that speculative accesses to these regions\nare indeed safe.\n\nIf the input program contains a function declaration such as:\n\nvoid foo (void);\n\nthen the implementation of \"foo\" must  allow  \"j  foo\"  and  \"jal  foo\"  to  be  executed\nspeculatively.  GCC honors this restriction for functions it compiles itself.  It expects\nnon-GCC functions (such as hand-written assembly code) to do the same.\n\nThe option has three forms:\n\n-mr10k-cache-barrier=load-store\nInsert  a  cache  barrier before a load or store that might be speculatively executed\nand that might have side effects even if aborted.\n\n-mr10k-cache-barrier=store\nInsert a cache barrier before a store that might be speculatively executed  and  that\nmight have side effects even if aborted.\n\n-mr10k-cache-barrier=none\nDisable the insertion of cache barriers.  This is the default setting.\n"
                },
                {
                    "name": "-mflush-func=_",
                    "content": ""
                },
                {
                    "name": "-mno-flush-func",
                    "content": "Specifies  the  function  to  call  to  flush the I and D caches, or to not call any such\nfunction.   If  called,  the  function  must  take  the  same  arguments  as  the  common\n\"flushfunc\",  that  is,  the  address  of the memory range for which the cache is being\nflushed, the size of the memory range, and the number 3  (to  flush  both  caches).   The\ndefault   depends  on  the  target  GCC  was  configured  for,  but  commonly  is  either\n\"flushfunc\" or \"cpuflush\".\n\nmbranch-cost=num\nSet the cost of branches to roughly num \"simple\"  instructions.   This  cost  is  only  a\nheuristic  and  is  not guaranteed to produce consistent results across releases.  A zero\ncost redundantly selects the default, which is based on the -mtune setting.\n"
                },
                {
                    "name": "-mbranch-likely",
                    "content": ""
                },
                {
                    "name": "-mno-branch-likely",
                    "content": "Enable or disable use of Branch Likely instructions, regardless of the  default  for  the\nselected  architecture.   By default, Branch Likely instructions may be generated if they\nare supported by the selected architecture.  An exception is for the  MIPS32  and  MIPS64\narchitectures and processors that implement those architectures; for those, Branch Likely\ninstructions  are not be generated by default because the MIPS32 and MIPS64 architectures\nspecifically deprecate their use.\n"
                },
                {
                    "name": "-mcompact-branches=never",
                    "content": ""
                },
                {
                    "name": "-mcompact-branches=optimal",
                    "content": ""
                },
                {
                    "name": "-mcompact-branches=always",
                    "content": "These options control  which  form  of  branches  will  be  generated.   The  default  is\n-mcompact-branches=optimal.\n\nThe  -mcompact-branches=never  option ensures that compact branch instructions will never\nbe generated.\n\nThe -mcompact-branches=always option ensures that a compact branch  instruction  will  be\ngenerated  if  available  for MIPS Release 6 onwards.  If a compact branch instruction is\nnot available (or pre-R6), a delay slot form of the branch will be used instead.\n\nIf it is used for MIPS16/microMIPS targets, it will be just ignored now.   The  behaviour\nfor  MIPS16/microMIPS  may  change  in  future,  since  they  do have some compact branch\ninstructions.\n\nThe -mcompact-branches=optimal option will cause a delay slot branch to be used if one is\navailable in the current ISA and the delay slot is successfully  filled.   If  the  delay\nslot is not filled, a compact branch will be chosen if one is available.\n"
                },
                {
                    "name": "-mfp-exceptions",
                    "content": ""
                },
                {
                    "name": "-mno-fp-exceptions",
                    "content": "Specifies  whether  FP  exceptions  are  enabled.   This  affects how FP instructions are\nscheduled for some processors.  The default is that FP exceptions are enabled.\n\nFor instance, on the SB-1, if FP exceptions are disabled,  and  we  are  emitting  64-bit\ncode, then we can use both FP pipes.  Otherwise, we can only use one FP pipe.\n"
                },
                {
                    "name": "-mvr4130-align",
                    "content": ""
                },
                {
                    "name": "-mno-vr4130-align",
                    "content": "The  VR4130 pipeline is two-way superscalar, but can only issue two instructions together\nif the first one is 8-byte aligned.  When this option is enabled,  GCC  aligns  pairs  of\ninstructions that it thinks should execute in parallel.\n\nThis  option  only  has an effect when optimizing for the VR4130.  It normally makes code\nfaster, but at the expense of making it bigger.  It is enabled by default at optimization\nlevel -O3.\n"
                },
                {
                    "name": "-msynci",
                    "content": ""
                },
                {
                    "name": "-mno-synci",
                    "content": "Enable (disable) generation of \"synci\" instructions on  architectures  that  support  it.\nThe  \"synci\"  instructions  (if  enabled) are generated when \"builtinclearcache\" is\ncompiled.\n\nThis option defaults to -mno-synci, but the default can be overridden by configuring  GCC\nwith --with-synci.\n\nWhen  compiling  code  for single processor systems, it is generally safe to use \"synci\".\nHowever, on many multi-core (SMP) systems, it does not invalidate the instruction  caches\non all cores and may lead to undefined behavior.\n"
                },
                {
                    "name": "-mrelax-pic-calls",
                    "content": ""
                },
                {
                    "name": "-mno-relax-pic-calls",
                    "content": "Try  to  turn  PIC calls that are normally dispatched via register $25 into direct calls.\nThis is only possible if the linker can resolve the destination at link time and  if  the\ndestination is within range for a direct call.\n\n-mrelax-pic-calls  is  the default if GCC was configured to use an assembler and a linker\nthat support the \".reloc\" assembly directive and -mexplicit-relocs is  in  effect.   With\n-mno-explicit-relocs,  this optimization can be performed by the assembler and the linker\nalone without help from the compiler.\n"
                },
                {
                    "name": "-mmcount-ra-address",
                    "content": ""
                },
                {
                    "name": "-mno-mcount-ra-address",
                    "content": "Emit (do not emit) code that allows \"mcount\" to modify  the  calling  function's  return\naddress.   When enabled, this option extends the usual \"mcount\" interface with a new ra-\naddress parameter, which has type \"intptrt *\" and is passed in register $12.   \"mcount\"\ncan then modify the return address by doing both of the following:\n\n*   Returning the new address in register $31.\n\n*   Storing the new address in \"*ra-address\", if ra-address is nonnull.\n\nThe default is -mno-mcount-ra-address.\n"
                },
                {
                    "name": "-mframe-header-opt",
                    "content": ""
                },
                {
                    "name": "-mno-frame-header-opt",
                    "content": "Enable  (disable)  frame  header  optimization  in  the o32 ABI.  When using the o32 ABI,\ncalling functions will allocate 16 bytes on the stack for the called  function  to  write\nout  register arguments.  When enabled, this optimization will suppress the allocation of\nthe frame header if it can be determined that it is unused.\n\nThis optimization is off by default at all optimization levels.\n"
                },
                {
                    "name": "-mlxc1-sxc1",
                    "content": ""
                },
                {
                    "name": "-mno-lxc1-sxc1",
                    "content": "When applicable, enable (disable) the generation of \"lwxc1\",  \"swxc1\",  \"ldxc1\",  \"sdxc1\"\ninstructions.  Enabled by default.\n"
                },
                {
                    "name": "-mmadd4",
                    "content": ""
                },
                {
                    "name": "-mno-madd4",
                    "content": "When  applicable,  enable  (disable)  the  generation of 4-operand \"madd.s\", \"madd.d\" and\nrelated instructions.  Enabled by default.\n\nMMIX Options\n\nThese options are defined for the MMIX:\n"
                },
                {
                    "name": "-mlibfuncs",
                    "content": ""
                },
                {
                    "name": "-mno-libfuncs",
                    "content": "Specify that intrinsic library functions  are  being  compiled,  passing  all  values  in\nregisters, no matter the size.\n"
                },
                {
                    "name": "-mepsilon",
                    "content": ""
                },
                {
                    "name": "-mno-epsilon",
                    "content": "Generate  floating-point  comparison  instructions  that compare with respect to the \"rE\"\nepsilon register.\n"
                },
                {
                    "name": "-mabi=mmixware",
                    "content": ""
                },
                {
                    "name": "-mabi=gnu",
                    "content": "Generate code that passes function parameters and  return  values  that  (in  the  called\nfunction)  are  seen  as registers $0 and up, as opposed to the GNU ABI which uses global\nregisters $231 and up.\n"
                },
                {
                    "name": "-mzero-extend",
                    "content": ""
                },
                {
                    "name": "-mno-zero-extend",
                    "content": "When reading data from memory in sizes shorter than 64  bits,  use  (do  not  use)  zero-\nextending load instructions by default, rather than sign-extending ones.\n"
                },
                {
                    "name": "-mknuthdiv",
                    "content": ""
                },
                {
                    "name": "-mno-knuthdiv",
                    "content": "Make  the  result  of  a division yielding a remainder have the same sign as the divisor.\nWith the default, -mno-knuthdiv, the sign of  the  remainder  follows  the  sign  of  the\ndividend.   Both  methods  are  arithmetically valid, the latter being almost exclusively\nused.\n"
                },
                {
                    "name": "-mtoplevel-symbols",
                    "content": ""
                },
                {
                    "name": "-mno-toplevel-symbols",
                    "content": "Prepend (do not prepend) a : to all global symbols, so the assembly code can be used with\nthe \"PREFIX\" assembly directive.\n"
                },
                {
                    "name": "-melf",
                    "content": "Generate an executable in the ELF format, rather than the default mmo format used by  the\nmmix simulator.\n"
                },
                {
                    "name": "-mbranch-predict",
                    "content": ""
                },
                {
                    "name": "-mno-branch-predict",
                    "content": "Use  (do  not  use)  the  probable-branch  instructions,  when  static  branch prediction\nindicates a probable branch.\n"
                },
                {
                    "name": "-mbase-addresses",
                    "content": ""
                },
                {
                    "name": "-mno-base-addresses",
                    "content": "Generate (do not  generate)  code  that  uses  base  addresses.   Using  a  base  address\nautomatically  generates  a  request  (handled  by  the  assembler  and the linker) for a\nconstant to be set up in a global register.  The register is used for one  or  more  base\naddress  requests  within  the  range  0 to 255 from the value held in the register.  The\ngenerally leads to short and fast code, but the number of different data items  that  can\nbe  addressed  is  limited.   This means that a program that uses lots of static data may\nrequire -mno-base-addresses.\n"
                },
                {
                    "name": "-msingle-exit",
                    "content": ""
                },
                {
                    "name": "-mno-single-exit",
                    "content": "Force (do not force) generated code to have a single exit point in each function.\n\nMN10300 Options\n\nThese -m options are defined for Matsushita MN10300 architectures:\n"
                },
                {
                    "name": "-mmult-bug",
                    "content": "Generate code to avoid bugs in the multiply  instructions  for  the  MN10300  processors.\nThis is the default.\n"
                },
                {
                    "name": "-mno-mult-bug",
                    "content": "Do  not  generate  code  to  avoid  bugs  in  the  multiply  instructions for the MN10300\nprocessors.\n"
                },
                {
                    "name": "-mam33",
                    "content": "Generate code using features specific to the AM33 processor.\n"
                },
                {
                    "name": "-mno-am33",
                    "content": "Do not generate code using features specific to the AM33 processor.  This is the default.\n"
                },
                {
                    "name": "-mam33-2",
                    "content": "Generate code using features specific to the AM33/2.0 processor.\n"
                },
                {
                    "name": "-mam34",
                    "content": "Generate code using features specific to the AM34 processor.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "Use the timing characteristics of the indicated CPU type  when  scheduling  instructions.\nThis  does  not change the targeted processor type.  The CPU type must be one of mn10300,\nam33, am33-2 or am34.\n"
                },
                {
                    "name": "-mreturn-pointer-on-d0",
                    "content": "When generating a function that returns a pointer, return the pointer in  both  \"a0\"  and\n\"d0\".   Otherwise,  the  pointer  is  returned  only  in  \"a0\", and attempts to call such\nfunctions without a prototype result in errors.  Note that this option is on by  default;\nuse -mno-return-pointer-on-d0 to disable it.\n"
                },
                {
                    "name": "-mno-crt0",
                    "content": "Do not link in the C run-time initialization object file.\n"
                },
                {
                    "name": "-mrelax",
                    "content": "Indicate  to  the linker that it should perform a relaxation optimization pass to shorten\nbranches, calls and absolute memory addresses.  This option only has an effect when  used\non the command line for the final link step.\n\nThis option makes symbolic debugging impossible.\n"
                },
                {
                    "name": "-mliw",
                    "content": "Allow  the  compiler  to generate Long Instruction Word instructions if the target is the\nAM33 or later.  This  is  the  default.   This  option  defines  the  preprocessor  macro\n\"LIW\".\n"
                },
                {
                    "name": "-mno-liw",
                    "content": "Do  not  allow  the compiler to generate Long Instruction Word instructions.  This option\ndefines the preprocessor macro \"NOLIW\".\n"
                },
                {
                    "name": "-msetlb",
                    "content": "Allow the compiler to generate the SETLB and Lcc instructions if the target is  the  AM33\nor later.  This is the default.  This option defines the preprocessor macro \"SETLB\".\n"
                },
                {
                    "name": "-mno-setlb",
                    "content": "Do not allow the compiler to generate SETLB or Lcc instructions.  This option defines the\npreprocessor macro \"NOSETLB\".\n\nMoxie Options\n"
                },
                {
                    "name": "-meb",
                    "content": "Generate big-endian code.  This is the default for moxie-*-* configurations.\n"
                },
                {
                    "name": "-mel",
                    "content": "Generate little-endian code.\n"
                },
                {
                    "name": "-mmul.x",
                    "content": "Generate   mul.x   and  umul.x  instructions.   This  is  the  default  for  moxiebox-*-*\nconfigurations.\n"
                },
                {
                    "name": "-mno-crt0",
                    "content": "Do not link in the C run-time initialization object file.\n\nMSP430 Options\n\nThese options are defined for the MSP430:\n"
                },
                {
                    "name": "-masm-hex",
                    "content": "Force assembly output to always use hex constants.  Normally such  constants  are  signed\ndecimals, but this option is available for testsuite and/or aesthetic purposes.\n"
                },
                {
                    "name": "-mmcu=",
                    "content": "Select  the MCU to target.  This is used to create a C preprocessor symbol based upon the\nMCU name, converted to upper case and pre- and post-fixed with .  This in turn is  used\nby the msp430.h header file to select an MCU-specific supplementary header file.\n\nThe  option  also  sets  the  ISA  to  use.  If the MCU name is one that is known to only\nsupport the 430 ISA then that is selected, otherwise the 430X ISA is selected.  A generic\nMCU name of msp430 can also be used to select the 430 ISA.  Similarly the generic msp430x\nMCU name selects the 430X ISA.\n\nIn addition an MCU-specific linker script is added  to  the  linker  command  line.   The\nscript's name is the name of the MCU with .ld appended.  Thus specifying -mmcu=xxx on the\ngcc  command  line  defines  the  C preprocessor symbol \"XXX\" and cause the linker to\nsearch for a script called xxx.ld.\n\nThe ISA and hardware multiply supported for the different MCUs is  hard-coded  into  GCC.\nHowever,  an  external devices.csv file can be used to extend device support beyond those\nthat have been hard-coded.\n\nGCC searches for the devices.csv file using the following methods in the given precedence\norder, where the first method takes precendence over the second  which  takes  precedence\nover the third.\n\nInclude path specified with \"-I\" and \"-L\"\ndevices.csv  will  be  searched  for  in each of the directories specified by include\npaths and linker library search paths.\n\nPath specified by the environment variable MSP430GCCINCLUDEDIR\nDefine the value of the global environment  variable  MSP430GCCINCLUDEDIR  to  the\nfull path to the directory containing devices.csv, and GCC will search this directory\nfor  devices.csv.  If devices.csv is found, this directory will also be registered as\nan include path, and linker library path.  Header files and linker  scripts  in  this\ndirectory  can  therefore  be  used  without manually specifying \"-I\" and \"-L\" on the\ncommand line.\n\nThe msp430-elf{,bare}/include/devices directory\nFinally, GCC will examine msp430-elf{,bare}/include/devices from the  toolchain  root\ndirectory.   This directory does not exist in a default installation, but if the user\nhas created it and copied devices.csv there, then the MCU  data  will  be  read.   As\nabove,  this directory will also be registered as an include path, and linker library\npath.\n\nIf none of the above search methods find devices.csv, then the  hard-coded  MCU  data  is\nused.\n"
                },
                {
                    "name": "-mwarn-mcu",
                    "content": ""
                },
                {
                    "name": "-mno-warn-mcu",
                    "content": "This  option  enables or disables warnings about conflicts between the MCU name specified\nby the -mmcu option and the ISA set by the -mcpu  option  and/or  the  hardware  multiply\nsupport  set  by  the  -mhwmult  option.  It also toggles warnings about unrecognized MCU\nnames.  This option is on by default.\n"
                },
                {
                    "name": "-mcpu=",
                    "content": "Specifies the ISA to use.  Accepted values  are  msp430,  msp430x  and  msp430xv2.   This\noption is deprecated.  The -mmcu= option should be used to select the ISA.\n"
                },
                {
                    "name": "-msim",
                    "content": "Link  to  the  simulator runtime libraries and linker script.  Overrides any scripts that\nwould be selected by the -mmcu= option.\n"
                },
                {
                    "name": "-mlarge",
                    "content": "Use large-model addressing (20-bit pointers, 20-bit \"sizet\").\n"
                },
                {
                    "name": "-msmall",
                    "content": "Use small-model addressing (16-bit pointers, 16-bit \"sizet\").\n"
                },
                {
                    "name": "-mrelax",
                    "content": "This option is passed to the assembler and linker,  and  allows  the  linker  to  perform\ncertain optimizations that cannot be done until the final link.\n"
                },
                {
                    "name": "mhwmult=",
                    "content": "Describes  the  type  of  hardware multiply supported by the target.  Accepted values are\nnone for no hardware multiply, 16bit for the original 16-bit-only multiply  supported  by\nearly  MCUs.   32bit  for the 16/32-bit multiply supported by later MCUs and f5series for\nthe 16/32-bit multiply supported by F5-series MCUs.  A value of auto can also  be  given.\nThis  tells  GCC to deduce the hardware multiply support based upon the MCU name provided\nby the -mmcu option.  If no -mmcu  option  is  specified  or  if  the  MCU  name  is  not\nrecognized then no hardware multiply support is assumed.  \"auto\" is the default setting.\n\nHardware  multiplies  are  normally  performed  by calling a library routine.  This saves\nspace in the generated code.  When compiling  at  -O3  or  higher  however  the  hardware\nmultiplier is invoked inline.  This makes for bigger, but faster code.\n\nThe hardware multiply routines disable interrupts whilst running and restore the previous\ninterrupt  state when they finish.  This makes them safe to use inside interrupt handlers\nas well as in normal code.\n"
                },
                {
                    "name": "-minrt",
                    "content": "Enable the use of a minimum runtime environment - no static initializers or constructors.\nThis is intended for memory-constrained devices.  The compiler includes  special  symbols\nin some objects that tell the linker and runtime which code fragments are required.\n"
                },
                {
                    "name": "-mtiny-printf",
                    "content": "Enable reduced code size \"printf\" and \"puts\" library functions.  The tiny implementations\nof  these  functions  are  not  reentrant, so must be used with caution in multi-threaded\napplications.\n\nSupport for streams has been removed and the string to be printed will always be sent  to\nstdout via the \"write\" syscall.  The string is not buffered before it is sent to write.\n\nThis   option   requires   Newlib   Nano   IO,   so   GCC   must   be   configured   with\n--enable-newlib-nano-formatted-io.\n"
                },
                {
                    "name": "-mmax-inline-shift=",
                    "content": "This option takes an integer between 0 and 64 inclusive, and sets the maximum  number  of\ninline  shift  instructions  which  should  be  emitted to perform a shift operation by a\nconstant amount.  When this value needs to be exceeded, an mspabi helper function is used\ninstead.  The default value is 4.\n\nThis only affects cases where a shift by multiple positions cannot be  completed  with  a\nsingle instruction (e.g. all shifts >1 on the 430 ISA).\n\nShifts  of  a  32-bit  value  are  at least twice as costly, so the value passed for this\noption is divided by 2 and the resulting value used instead.\n"
                },
                {
                    "name": "-mcode-region=",
                    "content": ""
                },
                {
                    "name": "-mdata-region=",
                    "content": "These options tell the compiler where to place functions and data that do not have one of\nthe \"lower\", \"upper\", \"either\" or \"section\" attributes.   Possible  values  are  \"lower\",\n\"upper\",  \"either\"  or  \"any\".   The first three behave like the corresponding attribute.\nThe fourth possible value - \"any\" - is the default.  It leaves placement entirely  up  to\nthe linker script and how it assigns the standard sections (\".text\", \".data\", etc) to the\nmemory regions.\n"
                },
                {
                    "name": "-msilicon-errata=",
                    "content": "This  option  passes  on a request to assembler to enable the fixes for the named silicon\nerrata.\n"
                },
                {
                    "name": "-msilicon-errata-warn=",
                    "content": "This option passes on a request to the  assembler  to  enable  warning  messages  when  a\nsilicon errata might need to be applied.\n"
                },
                {
                    "name": "-mwarn-devices-csv",
                    "content": ""
                },
                {
                    "name": "-mno-warn-devices-csv",
                    "content": "Warn if devices.csv is not found or there are problem parsing it (default: on).\n\nNDS32 Options\n\nThese options are defined for NDS32 implementations:\n"
                },
                {
                    "name": "-mbig-endian",
                    "content": "Generate code in big-endian mode.\n"
                },
                {
                    "name": "-mlittle-endian",
                    "content": "Generate code in little-endian mode.\n"
                },
                {
                    "name": "-mreduced-regs",
                    "content": "Use reduced-set registers for register allocation.\n"
                },
                {
                    "name": "-mfull-regs",
                    "content": "Use full-set registers for register allocation.\n"
                },
                {
                    "name": "-mcmov",
                    "content": "Generate conditional move instructions.\n"
                },
                {
                    "name": "-mno-cmov",
                    "content": "Do not generate conditional move instructions.\n"
                },
                {
                    "name": "-mext-perf",
                    "content": "Generate performance extension instructions.\n"
                },
                {
                    "name": "-mno-ext-perf",
                    "content": "Do not generate performance extension instructions.\n"
                },
                {
                    "name": "-mext-perf2",
                    "content": "Generate performance extension 2 instructions.\n"
                },
                {
                    "name": "-mno-ext-perf2",
                    "content": "Do not generate performance extension 2 instructions.\n"
                },
                {
                    "name": "-mext-string",
                    "content": "Generate string extension instructions.\n"
                },
                {
                    "name": "-mno-ext-string",
                    "content": "Do not generate string extension instructions.\n"
                },
                {
                    "name": "-mv3push",
                    "content": "Generate v3 push25/pop25 instructions.\n"
                },
                {
                    "name": "-mno-v3push",
                    "content": "Do not generate v3 push25/pop25 instructions.\n"
                },
                {
                    "name": "-m16-bit",
                    "content": "Generate 16-bit instructions.\n"
                },
                {
                    "name": "-mno-16-bit",
                    "content": "Do not generate 16-bit instructions.\n"
                },
                {
                    "name": "-misr-vector-size=_",
                    "content": "Specify the size of each interrupt vector, which must be 4 or 16.\n"
                },
                {
                    "name": "-mcache-block-size=_",
                    "content": "Specify the size of each cache block, which must be a power of 2 between 4 and 512.\n"
                },
                {
                    "name": "-march=_",
                    "content": "Specify the name of the target architecture.\n"
                },
                {
                    "name": "-mcmodel=_",
                    "content": "Set the code model to one of\n\nsmall\nAll  the data and read-only data segments must be within 512KB addressing space.  The\ntext segment must be within 16MB addressing space.\n\nmedium\nThe data segment must be within 512KB while the read-only data segment can be  within\n4GB addressing space.  The text segment should be still within 16MB addressing space.\n\nlarge\nAll the text and data segments can be within 4GB addressing space.\n"
                },
                {
                    "name": "-mctor-dtor",
                    "content": "Enable constructor/destructor feature.\n"
                },
                {
                    "name": "-mrelax",
                    "content": "Guide linker to relax instructions.\n\nNios II Options\n\nThese are the options defined for the Altera Nios II processor.\n"
                },
                {
                    "name": "-G _",
                    "content": "Put  global and static objects less than or equal to num bytes into the small data or BSS\nsections instead of the normal data or BSS sections.  The default value of num is 8.\n",
                    "flag": "-G"
                },
                {
                    "name": "-mgpopt=_",
                    "content": ""
                },
                {
                    "name": "-mgpopt",
                    "content": ""
                },
                {
                    "name": "-mno-gpopt",
                    "content": "Generate (do  not  generate)  GP-relative  accesses.   The  following  option  names  are\nrecognized:\n\nnone\nDo not generate GP-relative accesses.\n\nlocal\nGenerate  GP-relative accesses for small data objects that are not external, weak, or\nuninitialized common symbols.  Also use GP-relative addressing for objects that  have\nbeen explicitly placed in a small data section via a \"section\" attribute.\n\nglobal\nAs  for local, but also generate GP-relative accesses for small data objects that are\nexternal, weak, or common.  If you use this option, you must ensure that all parts of\nyour program (including libraries) are compiled with the same -G setting.\n\ndata\nGenerate GP-relative accesses for all data objects in the program.  If you  use  this\noption,  the  entire  data and BSS segments of your program must fit in 64K of memory\nand you must use an appropriate linker script to allocate them within the addressable\nrange of the global pointer.\n\nall Generate GP-relative addresses for function pointers as well as  data  pointers.   If\nyou use this option, the entire text, data, and BSS segments of your program must fit\nin  64K  of  memory  and  you  must use an appropriate linker script to allocate them\nwithin the addressable range of the global pointer.\n\n-mgpopt is equivalent to -mgpopt=local, and -mno-gpopt is equivalent to -mgpopt=none.\n\nThe default is -mgpopt except when -fpic or -fPIC  is  specified  to  generate  position-\nindependent  code.   Note  that the Nios II ABI does not permit GP-relative accesses from\nshared libraries.\n\nYou may need to specify -mno-gpopt explicitly when building programs that  include  large\namounts  of  small  data,  including  large  GOT data sections.  In this case, the 16-bit\noffset for GP-relative addressing may not be large enough to allow access to  the  entire\nsmall data section.\n"
                },
                {
                    "name": "-mgprel-sec=_",
                    "content": "This  option  specifies  additional  section  names  that can be accessed via GP-relative\naddressing.  It is most useful in  conjunction  with  \"section\"  attributes  on  variable\ndeclarations  and  a  custom  linker  script.   The  regexp  is  a POSIX Extended Regular\nExpression.\n\nThis option does not affect the behavior of the -G option, and the specified sections are\nin addition to the standard \".sdata\" and \".sbss\" small-data sections that are  recognized\nby -mgpopt.\n"
                },
                {
                    "name": "-mr0rel-sec=_",
                    "content": "This  option  specifies  names  of sections that can be accessed via a 16-bit offset from\n\"r0\"; that is, in the low 32K or high 32K of the 32-bit address space.  It is most useful\nin conjunction with \"section\" attributes on variable declarations  and  a  custom  linker\nscript.  The regexp is a POSIX Extended Regular Expression.\n\nIn contrast to the use of GP-relative addressing for small data, zero-based addressing is\nnever  generated  by default and there are no conventional section names used in standard\nlinker scripts for sections in the low or high areas of memory.\n"
                },
                {
                    "name": "-mel",
                    "content": ""
                },
                {
                    "name": "-meb",
                    "content": "Generate little-endian (default) or big-endian (experimental) code, respectively.\n"
                },
                {
                    "name": "-march=_",
                    "content": "This specifies the name of the target Nios  II  architecture.   GCC  uses  this  name  to\ndetermine  what  kind  of  instructions  it  can  emit  when  generating  assembly  code.\nPermissible names are: r1, r2.\n\nThe preprocessor macro \"nios2arch\" is available to programs,  with  value  1  or  2,\nindicating the targeted ISA level.\n"
                },
                {
                    "name": "-mbypass-cache",
                    "content": ""
                },
                {
                    "name": "-mno-bypass-cache",
                    "content": "Force all load and store instructions to always bypass cache by using I/O variants of the\ninstructions. The default is not to bypass the cache.\n"
                },
                {
                    "name": "-mno-cache-volatile",
                    "content": ""
                },
                {
                    "name": "-mcache-volatile",
                    "content": "Volatile  memory  access  bypass  the  cache using the I/O variants of the load and store\ninstructions. The default is not to bypass the cache.\n"
                },
                {
                    "name": "-mno-fast-sw-div",
                    "content": ""
                },
                {
                    "name": "-mfast-sw-div",
                    "content": "Do not use table-based fast divide for small numbers. The default  is  to  use  the  fast\ndivide at -O3 and above.\n"
                },
                {
                    "name": "-mno-hw-mul",
                    "content": ""
                },
                {
                    "name": "-mhw-mul",
                    "content": ""
                },
                {
                    "name": "-mno-hw-mulx",
                    "content": ""
                },
                {
                    "name": "-mhw-mulx",
                    "content": ""
                },
                {
                    "name": "-mno-hw-div",
                    "content": ""
                },
                {
                    "name": "-mhw-div",
                    "content": "Enable  or  disable  emitting  \"mul\",  \"mulx\"  and  \"div\"  family  of instructions by the\ncompiler. The default is to emit \"mul\" and not emit \"div\" and \"mulx\".\n"
                },
                {
                    "name": "-mbmx",
                    "content": ""
                },
                {
                    "name": "-mno-bmx",
                    "content": ""
                },
                {
                    "name": "-mcdx",
                    "content": ""
                },
                {
                    "name": "-mno-cdx",
                    "content": "Enable or disable generation of Nios II R2 BMX (bit manipulation) and CDX (code  density)\ninstructions.    Enabling  these  instructions  also  requires  -march=r2.   Since  these\ninstructions are optional extensions to the R2 architecture, the default is not  to  emit\nthem.\n"
                },
                {
                    "name": "-mcustom-_",
                    "content": ""
                },
                {
                    "name": "-mno-custom-_",
                    "content": "Each  -mcustom-insn=N  option  enables  use  of a custom instruction with encoding N when\ngenerating code  that  uses  insn.   For  example,  -mcustom-fadds=253  generates  custom\ninstruction 253 for single-precision floating-point add operations instead of the default\nbehavior of using a library call.\n\nThe  following  values  of insn are supported.  Except as otherwise noted, floating-point\noperations are expected to be implemented with normal IEEE 754 semantics  and  correspond\ndirectly to the C operators or the equivalent GCC built-in functions.\n\nSingle-precision floating point:\n\nfadds, fsubs, fdivs, fmuls\nBinary arithmetic operations.\n\nfnegs\nUnary negation.\n\nfabss\nUnary absolute value.\n\nfcmpeqs, fcmpges, fcmpgts, fcmples, fcmplts, fcmpnes\nComparison operations.\n\nfmins, fmaxs\nFloating-point  minimum  and  maximum.   These  instructions  are  only  generated if\n-ffinite-math-only is specified.\n\nfsqrts\nUnary square root operation.\n\nfcoss, fsins, ftans, fatans, fexps, flogs\nFloating-point trigonometric and exponential functions.  These instructions are  only\ngenerated if -funsafe-math-optimizations is also specified.\n\nDouble-precision floating point:\n\nfaddd, fsubd, fdivd, fmuld\nBinary arithmetic operations.\n\nfnegd\nUnary negation.\n\nfabsd\nUnary absolute value.\n\nfcmpeqd, fcmpged, fcmpgtd, fcmpled, fcmpltd, fcmpned\nComparison operations.\n\nfmind, fmaxd\nDouble-precision  minimum  and  maximum.   These  instructions  are only generated if\n-ffinite-math-only is specified.\n\nfsqrtd\nUnary square root operation.\n\nfcosd, fsind, ftand, fatand, fexpd, flogd\nDouble-precision trigonometric and exponential  functions.   These  instructions  are\nonly generated if -funsafe-math-optimizations is also specified.\n\nConversions:\n\nfextsd\nConversion from single precision to double precision.\n\nftruncds\nConversion from double precision to single precision.\n\nfixsi, fixsu, fixdi, fixdu\nConversion  from  floating point to signed or unsigned integer types, with truncation\ntowards zero.\n\nround\nConversion from single-precision floating point to signed integer,  rounding  to  the\nnearest integer and ties away from zero.  This corresponds to the \"builtinlroundf\"\nfunction when -fno-math-errno is used.\n\nfloatis, floatus, floatid, floatud\nConversion from signed or unsigned integer types to floating-point types.\n\nIn  addition,  all  of the following transfer instructions for internal registers X and Y\nmust be provided to use any of the double-precision floating-point instructions.   Custom\ninstructions  taking two double-precision source operands expect the first operand in the\n64-bit register X.  The other operand (or only operand of a unary operation) is given  to\nthe custom arithmetic instruction with the least significant half in source register src1\nand  the  most  significant  half  in  src2.  A custom instruction that returns a double-\nprecision result returns the most significant 32 bits in the destination register and the\nother half in  32-bit  register  Y.   GCC  automatically  generates  the  necessary  code\nsequences to write register X and/or read register Y when double-precision floating-point\ninstructions are used.\n\nfwrx\nWrite  src1  into  the least significant half of X and src2 into the most significant\nhalf of X.\n\nfwry\nWrite src1 into Y.\n\nfrdxhi, frdxlo\nRead the most or least (respectively) significant half of X and store it in dest.\n\nfrdy\nRead the value of Y and store it into dest.\n\nNote that you can gain more local control over generation of Nios II custom  instructions\nby  using the target(\"custom-insn=N\") and target(\"no-custom-insn\") function attributes or\npragmas.\n"
                },
                {
                    "name": "-mcustom-fpu-cfg=_",
                    "content": "This option enables  a  predefined,  named  set  of  custom  instruction  encodings  (see\n-mcustom-insn above).  Currently, the following sets are defined:\n\n-mcustom-fpu-cfg=60-1    is    equivalent   to:   -mcustom-fmuls=252   -mcustom-fadds=253\n-mcustom-fsubs=254 -fsingle-precision-constant\n\n-mcustom-fpu-cfg=60-2   is   equivalent   to:    -mcustom-fmuls=252    -mcustom-fadds=253\n-mcustom-fsubs=254 -mcustom-fdivs=255 -fsingle-precision-constant\n\n-mcustom-fpu-cfg=72-3   is   equivalent   to:   -mcustom-floatus=243   -mcustom-fixsi=244\n-mcustom-floatis=245   -mcustom-fcmpgts=246   -mcustom-fcmples=249   -mcustom-fcmpeqs=250\n-mcustom-fcmpnes=251     -mcustom-fmuls=252     -mcustom-fadds=253     -mcustom-fsubs=254\n-mcustom-fdivs=255 -fsingle-precision-constant\n\n-mcustom-fpu-cfg=fph2   is   equivalent   to:    -mcustom-fabss=224    -mcustom-fnegs=225\n-mcustom-fcmpnes=226   -mcustom-fcmpeqs=227   -mcustom-fcmpges=228   -mcustom-fcmpgts=229\n-mcustom-fcmples=230    -mcustom-fcmplts=231    -mcustom-fmaxs=232     -mcustom-fmins=233\n-mcustom-round=248     -mcustom-fixsi=249     -mcustom-floatis=250    -mcustom-fsqrts=251\n-mcustom-fmuls=252 -mcustom-fadds=253 -mcustom-fsubs=254 -mcustom-fdivs=255\n\nCustom instruction assignments given by individual -mcustom-insn= options override  those\ngiven by -mcustom-fpu-cfg=, regardless of the order of the options on the command line.\n\nNote  that you can gain more local control over selection of a FPU configuration by using\nthe target(\"custom-fpu-cfg=name\") function attribute or pragma.\n\nThe name fph2 is an abbreviation for Nios II Floating Point Hardware 2 Component.  Please\nnote that the custom instructions enabled by  -mcustom-fmins=233  and  -mcustom-fmaxs=234\nare only generated if -ffinite-math-only is specified.  The custom instruction enabled by\n-mcustom-round=248 is only generated if -fno-math-errno is specified.  In contrast to the\nother configurations, -fsingle-precision-constant is not set.\n\nThese additional -m options are available for the Altera Nios II ELF (bare-metal) target:\n"
                },
                {
                    "name": "-mhal",
                    "content": "Link  with  HAL BSP.  This suppresses linking with the GCC-provided C runtime startup and\ntermination code, and is typically used in conjunction with -msys-crt0=  to  specify  the\nlocation of the alternate startup code provided by the HAL BSP.\n"
                },
                {
                    "name": "-msmallc",
                    "content": "Link with a limited version of the C library, -lsmallc, rather than Newlib.\n"
                },
                {
                    "name": "-msys-crt0=_",
                    "content": "startfile  is  the file name of the startfile (crt0) to use when linking.  This option is\nonly useful in conjunction with -mhal.\n"
                },
                {
                    "name": "-msys-lib=_",
                    "content": "systemlib is the library name  of  the  library  that  provides  low-level  system  calls\nrequired  by  the  C  library, e.g. \"read\" and \"write\".  This option is typically used to\nlink with a library provided by a HAL BSP.\n\nNvidia PTX Options\n\nThese options are defined for Nvidia PTX:\n"
                },
                {
                    "name": "-m64",
                    "content": "Ignored, but preserved for backward compatibility.  Only 64-bit ABI is supported.\n"
                },
                {
                    "name": "-march=_",
                    "content": "Generate code for  the  specified  PTX  ISA  target  architecture  (e.g.  sm35).   Valid\narchitecture  strings  are  sm30,  sm35,  sm53,  sm70,  sm75 and sm80.  The default\ndepends on how the compiler has been configured, see --with-arch.\n\nThis option sets the value of the preprocessor  macro  \"PTXSM\";  for  instance,  for\nsm35, it has the value 350.\n"
                },
                {
                    "name": "-misa=_",
                    "content": "Alias of -march=.\n"
                },
                {
                    "name": "-march-map=_",
                    "content": "Select  the  closest available -march= value that is not more capable.  For instance, for\n-march-map=sm50 select -march=sm35, and for -march-map=sm53 select -march=sm53.\n"
                },
                {
                    "name": "-mptx=_",
                    "content": "Generate code for the specified PTX  ISA  version  (e.g.  7.0).   Valid  version  strings\ninclude  3.1,  6.0,  6.3,  and  7.0.  The default PTX ISA version is 6.0, unless a higher\nversion is required for specified PTX ISA target architecture via option -march=.\n\nThis option sets the values of the preprocessor  macros  \"PTXISAVERSIONMAJOR\"  and\n\"PTXISAVERSIONMINOR\";  for  instance,  for 3.1 the macros have the values 3 and 1,\nrespectively.\n"
                },
                {
                    "name": "-mmainkernel",
                    "content": "Link in code for a  main  kernel.   This  is  for  stand-alone  instead  of  offloading\nexecution.\n"
                },
                {
                    "name": "-moptimize",
                    "content": "Apply  partitioned  execution  optimizations.   This  is  the  default  when any level of\noptimization is selected.\n"
                },
                {
                    "name": "-msoft-stack",
                    "content": "Generate code that does not use \".local\" memory directly for stack  storage.  Instead,  a\nper-warp  stack  pointer  is  maintained  explicitly.  This enables variable-length stack\nallocation (with variable-length arrays or \"alloca\"), and when global memory is used  for\nunderlying  storage,  makes it possible to access automatic variables from other threads,\nor with atomic instructions. This code generation variant is used for OpenMP  offloading,\nbut the option is exposed on its own for the purpose of testing the compiler; to generate\ncode suitable for linking into programs using OpenMP offloading, use option -mgomp.\n"
                },
                {
                    "name": "-muniform-simt",
                    "content": "Switch  to code generation variant that allows to execute all threads in each warp, while\nmaintaining memory state and side effects as if only one thread in each warp  was  active\noutside  of  OpenMP  SIMD  regions.   All atomic operations and calls to runtime (malloc,\nfree, vprintf) are conditionally executed (iff current lane index equals the master  lane\nindex),  and  the  register  being  assigned is copied via a shuffle instruction from the\nmaster lane.  Outside of SIMD regions lane 0 is the  master;  inside,  each  thread  sees\nitself  as  the master.  Shared memory array \"int nvptxuni[]\" stores all-zeros or all-\nones bitmasks for each warp, indicating current mode (0 outside of SIMD  regions).   Each\nthread can bitwise-and the bitmask at position \"tid.y\" with current lane index to compute\nthe master lane index.\n"
                },
                {
                    "name": "-mgomp",
                    "content": "Generate  code  for  use  in  OpenMP  offloading: enables -msoft-stack and -muniform-simt\noptions, and selects corresponding multilib variant.\n\nOpenRISC Options\n\nThese options are defined for OpenRISC:\n"
                },
                {
                    "name": "-mboard=_",
                    "content": "Configure a board specific runtime.  This will be passed to the linker for  newlib  board\nlibrary linking.  The default is \"or1ksim\".\n"
                },
                {
                    "name": "-mnewlib",
                    "content": "This  option  is  ignored;  it  is  for compatibility purposes only.  This used to select\nlinker and preprocessor options for use with newlib.\n"
                },
                {
                    "name": "-msoft-div",
                    "content": ""
                },
                {
                    "name": "-mhard-div",
                    "content": "Select software or hardware divide (\"l.div\", \"l.divu\")  instructions.   This  default  is\nhardware divide.\n"
                },
                {
                    "name": "-msoft-mul",
                    "content": ""
                },
                {
                    "name": "-mhard-mul",
                    "content": "Select  software  or hardware multiply (\"l.mul\", \"l.muli\") instructions.  This default is\nhardware multiply.\n"
                },
                {
                    "name": "-msoft-float",
                    "content": ""
                },
                {
                    "name": "-mhard-float",
                    "content": "Select software or hardware for floating point operations.  The default is software.\n"
                },
                {
                    "name": "-mdouble-float",
                    "content": "When -mhard-float is selected, enables  generation  of  double-precision  floating  point\ninstructions.   By  default  functions  from  libgcc are used to perform double-precision\nfloating point operations.\n"
                },
                {
                    "name": "-munordered-float",
                    "content": "When -mhard-float is selected, enables generation of unordered floating point compare and\nset flag (\"lf.sfun*\") instructions.  By default functions from libgcc are used to perform\nunordered floating point compare and set flag operations.\n"
                },
                {
                    "name": "-mcmov",
                    "content": "Enable generation of conditional move (\"l.cmov\") instructions.  By default the equivalent\nwill be generated using set and branch.\n"
                },
                {
                    "name": "-mror",
                    "content": "Enable generation of rotate right (\"l.ror\")  instructions.   By  default  functions  from\nlibgcc are used to perform rotate right operations.\n"
                },
                {
                    "name": "-mrori",
                    "content": "Enable  generation  of  rotate  right with immediate (\"l.rori\") instructions.  By default\nfunctions from libgcc are used to perform rotate right with immediate operations.\n"
                },
                {
                    "name": "-msext",
                    "content": "Enable generation of sign extension (\"l.ext*\") instructions.  By default memory loads are\nused to perform sign extension.\n"
                },
                {
                    "name": "-msfimm",
                    "content": "Enable generation of compare and set flag with  immediate  (\"l.sf*i\")  instructions.   By\ndefault extra instructions will be generated to store the immediate to a register first.\n"
                },
                {
                    "name": "-mshftimm",
                    "content": "Enable  generation  of  shift with immediate (\"l.srai\", \"l.srli\", \"l.slli\") instructions.\nBy default extra instructions will be generated to store  the  immediate  to  a  register\nfirst.\n"
                },
                {
                    "name": "-mcmodel=small",
                    "content": "Generate  OpenRISC  code  for  the  small  model:  The GOT is limited to 64k. This is the\ndefault model.\n"
                },
                {
                    "name": "-mcmodel=large",
                    "content": "Generate OpenRISC code for the large model: The GOT may grow up to 4G in size.\n\nPDP-11 Options\n\nThese options are defined for the PDP-11:\n"
                },
                {
                    "name": "-mfpu",
                    "content": "Use hardware FPP floating point.  This is  the  default.   (FIS  floating  point  on  the\nPDP-11/40 is not supported.)  Implies -m45.\n"
                },
                {
                    "name": "-msoft-float",
                    "content": "Do not use hardware floating point.\n"
                },
                {
                    "name": "-mac0",
                    "content": "Return floating-point results in ac0 (fr0 in Unix assembler syntax).\n"
                },
                {
                    "name": "-mno-ac0",
                    "content": "Return floating-point results in memory.  This is the default.\n"
                },
                {
                    "name": "-m40",
                    "content": "Generate code for a PDP-11/40.  Implies -msoft-float -mno-split.\n"
                },
                {
                    "name": "-m45",
                    "content": "Generate code for a PDP-11/45.  This is the default.\n"
                },
                {
                    "name": "-m10",
                    "content": "Generate code for a PDP-11/10.  Implies -msoft-float -mno-split.\n"
                },
                {
                    "name": "-mint16",
                    "content": ""
                },
                {
                    "name": "-mno-int32",
                    "content": "Use 16-bit \"int\".  This is the default.\n"
                },
                {
                    "name": "-mint32",
                    "content": ""
                },
                {
                    "name": "-mno-int16",
                    "content": "Use 32-bit \"int\".\n"
                },
                {
                    "name": "-msplit",
                    "content": "Target has split instruction and data space.  Implies -m45.\n"
                },
                {
                    "name": "-munix-asm",
                    "content": "Use Unix assembler syntax.\n"
                },
                {
                    "name": "-mdec-asm",
                    "content": "Use DEC assembler syntax.\n"
                },
                {
                    "name": "-mgnu-asm",
                    "content": "Use GNU assembler syntax.  This is the default.\n"
                },
                {
                    "name": "-mlra",
                    "content": "Use the new LRA register allocator.  By default, the old \"reload\" allocator is used.\n\nPowerPC Options\n\nThese are listed under\n\nPRU Options\n\nThese command-line options are defined for PRU target:\n"
                },
                {
                    "name": "-minrt",
                    "content": "Link  with  a  minimum  runtime  environment, with no support for static initializers and\nconstructors.  Using this option can significantly reduce  the  size  of  the  final  ELF\nbinary.   Beware that the compiler could still generate code with static initializers and\nconstructors.  It is up to the programmer to ensure that the source program will not  use\nthose features.\n"
                },
                {
                    "name": "-mmcu=_",
                    "content": "Specify the PRU MCU variant to use.  Check Newlib for the exact list of supported MCUs.\n"
                },
                {
                    "name": "-mno-relax",
                    "content": "Make  GCC  pass  the  --no-relax command-line option to the linker instead of the --relax\noption.\n"
                },
                {
                    "name": "-mloop",
                    "content": "Allow (or do not allow) GCC to use the LOOP instruction.\n"
                },
                {
                    "name": "-mabi=_",
                    "content": "Specify the ABI variant to output code for.  -mabi=ti selects the unmodified TI ABI while\n-mabi=gnu selects a GNU variant that copes more naturally with certain  GCC  assumptions.\nThese are the differences:\n\nFunction Pointer Size\nTI  ABI specifies that function (code) pointers are 16-bit, whereas GNU supports only\n32-bit data and code pointers.\n\nOptional Return Value Pointer\nFunction return values larger than 64 bits are passed by using a  hidden  pointer  as\nthe first argument of the function.  TI ABI, though, mandates that the pointer can be\nNULL  in  case  the  caller  is  not using the returned value.  GNU always passes and\nexpects a valid return value pointer.\n\nThe current -mabi=ti implementation simply raises a compile error when any of  the  above\ncode constructs is detected.  As a consequence the standard C library cannot be built and\nit is omitted when linking with -mabi=ti.\n\nRelaxation  is a GNU feature and for safety reasons is disabled when using -mabi=ti.  The\nTI toolchain does not emit relocations for QBBx instructions, so the  GNU  linker  cannot\nadjust them when shortening adjacent LDI32 pseudo instructions.\n\nRISC-V Options\n\nThese command-line options are defined for RISC-V targets:\n"
                },
                {
                    "name": "-mbranch-cost=_",
                    "content": "Set the cost of branches to roughly n instructions.\n"
                },
                {
                    "name": "-mplt",
                    "content": ""
                },
                {
                    "name": "-mno-plt",
                    "content": "When  generating  PIC  code, do or don't allow the use of PLTs. Ignored for non-PIC.  The\ndefault is -mplt.\n"
                },
                {
                    "name": "-mabi=_",
                    "content": "Specify integer and floating-point calling convention.  ABI-string  contains  two  parts:\nthe  size  of integer types and the registers used for floating-point types.  For example\n-march=rv64ifd -mabi=lp64d means that long and pointers are 64-bit  (implicitly  defining\nint  to  be  32-bit),  and  that floating-point values up to 64 bits wide are passed in F\nregisters.  Contrast  this  with  -march=rv64ifd  -mabi=lp64f,  which  still  allows  the\ncompiler to generate code that uses the F and D extensions but only allows floating-point\nvalues  up  to  32  bits long to be passed in registers; or -march=rv64ifd -mabi=lp64, in\nwhich no floating-point arguments will be passed in registers.\n\nThe default for this argument is system dependent, users  who  want  a  specific  calling\nconvention  should  specify  one  explicitly.   The valid calling conventions are: ilp32,\nilp32f, ilp32d, lp64, lp64f, and lp64d.   Some  calling  conventions  are  impossible  to\nimplement  on  some  ISAs: for example, -march=rv32if -mabi=ilp32d is invalid because the\nABI requires 64-bit values be passed in F registers, but F registers  are  only  32  bits\nwide.   There  is  also the ilp32e ABI that can only be used with the rv32e architecture.\nThis ABI is not well specified at present, and is subject to change.\n"
                },
                {
                    "name": "-mfdiv",
                    "content": ""
                },
                {
                    "name": "-mno-fdiv",
                    "content": "Do or don't use hardware  floating-point  divide  and  square  root  instructions.   This\nrequires  the F or D extensions for floating-point registers.  The default is to use them\nif the specified architecture has these instructions.\n"
                },
                {
                    "name": "-mdiv",
                    "content": ""
                },
                {
                    "name": "-mno-div",
                    "content": "Do or don't use  hardware  instructions  for  integer  division.   This  requires  the  M\nextension.   The  default  is  to  use  them  if  the  specified  architecture  has these\ninstructions.\n"
                },
                {
                    "name": "-misa-spec=_",
                    "content": "Specify the version of the RISC-V Unprivileged (formerly User-Level) ISA specification to\nproduce code conforming to.  The possibilities for ISA-spec-string are:\n\n2.2 Produce code conforming to version 2.2.\n\n20190608\nProduce code conforming to version 20190608.\n\n20191213\nProduce code conforming to version 20191213.\n\nThe default is -misa-spec=20191213 unless GCC has been configured  with  --with-isa-spec=\nspecifying a different default version.\n"
                },
                {
                    "name": "-march=_",
                    "content": "Generate  code  for  given  RISC-V  ISA  (e.g.  rv64im).  ISA strings must be lower-case.\nExamples include rv64i, rv32g, rv32e, and rv32imaf.\n\nWhen -march= is not specified, use the setting from -mcpu.\n\nIf both -march and -mcpu= are not specified, the default  for  this  argument  is  system\ndependent,  users  who  want  a  specific  architecture  extensions  should  specify  one\nexplicitly.\n"
                },
                {
                    "name": "-mcpu=_",
                    "content": "Use architecture of and optimize  the  output  for  the  given  processor,  specified  by\nparticular  CPU  name.   Permissible  values for this option are: sifive-e20, sifive-e21,\nsifive-e24,  sifive-e31,  sifive-e34,  sifive-e76,  sifive-s21,  sifive-s51,  sifive-s54,\nsifive-s76, sifive-u54, and sifive-u74.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "Optimize the output for the given processor, specified by microarchitecture or particular\nCPU   name.    Permissible   values   for   this  option  are:  rocket,  sifive-3-series,\nsifive-5-series, sifive-7-series, thead-c906, size, and all valid options for -mcpu=.\n\nWhen -mtune= is not specified, use the setting from -mcpu, the default is rocket if  both\nare not specified.\n\nThe  size  choice  is  not  intended  for  use  by  end-users.   This is used when -Os is\nspecified.  It overrides the instruction cost info provided  by  -mtune=,  but  does  not\noverride  the  pipeline  info.   This  helps  reduce  code  size  while still giving good\nperformance.\n"
                },
                {
                    "name": "-mpreferred-stack-boundary=_",
                    "content": "Attempt to keep the stack boundary aligned to a  2  raised  to  num  byte  boundary.   If\n-mpreferred-stack-boundary is not specified, the default is 4 (16 bytes or 128-bits).\n\nWarning:  If  you  use  this switch, then you must build all modules with the same value,\nincluding any libraries.  This includes the system libraries and startup modules.\n"
                },
                {
                    "name": "-msmall-data-limit=_",
                    "content": "Put global and static data smaller than n bytes into a special section (on some targets).\n"
                },
                {
                    "name": "-msave-restore",
                    "content": ""
                },
                {
                    "name": "-mno-save-restore",
                    "content": "Do or don't use smaller but slower prologue and epilogue code that uses library  function\ncalls.  The default is to use fast inline prologues and epilogues.\n"
                },
                {
                    "name": "-minline-atomics",
                    "content": ""
                },
                {
                    "name": "-mno-inline-atomics",
                    "content": "Do  or  don't  use  smaller  but slower subword atomic emulation code that uses libatomic\nfunction calls.  The default is to use fast inline subword atomics that  do  not  require\nlibatomic.\n"
                },
                {
                    "name": "-mshorten-memrefs",
                    "content": ""
                },
                {
                    "name": "-mno-shorten-memrefs",
                    "content": "Do  or do not attempt to make more use of compressed load/store instructions by replacing\na load/store of 'base register + large offset' with a new load/store of 'new base + small\noffset'.  If the new base gets stored in a compressed register, then the  new  load/store\ncan be compressed.  Currently targets 32-bit integer load/stores only.\n"
                },
                {
                    "name": "-mstrict-align",
                    "content": ""
                },
                {
                    "name": "-mno-strict-align",
                    "content": "Do not or do generate unaligned memory accesses.  The default is set depending on whether\nthe processor we are optimizing for supports fast unaligned access or not.\n"
                },
                {
                    "name": "-mcmodel=medlow",
                    "content": "Generate  code  for  the  medium-low  code  model. The program and its statically defined\nsymbols must lie within a single 2 GiB  address  range  and  must  lie  between  absolute\naddresses  -2  GiB  and +2 GiB. Programs can be statically or dynamically linked. This is\nthe default code model.\n"
                },
                {
                    "name": "-mcmodel=medany",
                    "content": "Generate code for the medium-any code model.  The  program  and  its  statically  defined\nsymbols  must  be  within  any  single 2 GiB address range. Programs can be statically or\ndynamically linked.\n\nThe code generated by the medium-any code  model  is  position-independent,  but  is  not\nguaranteed  to  function  correctly  when linked into position-independent executables or\nlibraries.\n"
                },
                {
                    "name": "-mexplicit-relocs",
                    "content": ""
                },
                {
                    "name": "-mno-exlicit-relocs",
                    "content": "Use or do not use assembler relocation operators when dealing  with  symbolic  addresses.\nThe alternative is to use assembler macros instead, which may limit optimization.\n"
                },
                {
                    "name": "-mrelax",
                    "content": ""
                },
                {
                    "name": "-mno-relax",
                    "content": "Take  advantage  of  linker  relaxations to reduce the number of instructions required to\nmaterialize symbol addresses. The default is to take advantage of linker relaxations.\n"
                },
                {
                    "name": "-mriscv-attribute",
                    "content": ""
                },
                {
                    "name": "-mno-riscv-attribute",
                    "content": "Emit (do not emit) RISC-V attribute to record extra information into ELF  objects.   This\nfeature requires at least binutils 2.32.\n"
                },
                {
                    "name": "-mcsr-check",
                    "content": ""
                },
                {
                    "name": "-mno-csr-check",
                    "content": "Enables or disables the CSR checking.\n"
                },
                {
                    "name": "-malign-data=_",
                    "content": "Control  how  GCC  aligns  variables  and  constants of array, structure, or union types.\nSupported values for type are xlen which uses x register width as  the  alignment  value,\nand natural which uses natural alignment.  xlen is the default.\n"
                },
                {
                    "name": "-mbig-endian",
                    "content": "Generate big-endian code.  This is the default when GCC is configured for a riscv64be-*-*\nor riscv32be-*-* target.\n"
                },
                {
                    "name": "-mlittle-endian",
                    "content": "Generate  little-endian  code.   This  is  the  default  when  GCC  is  configured  for a\nriscv64-*-* or riscv32-*-* but not a riscv64be-*-* or riscv32be-*-* target.\n"
                },
                {
                    "name": "-mstack-protector-guard=_",
                    "content": ""
                },
                {
                    "name": "-mstack-protector-guard-reg=_",
                    "content": ""
                },
                {
                    "name": "-mstack-protector-guard-offset=_",
                    "content": "Generate stack protection code using canary at guard.  Supported locations are global for\na global canary or tls for per-thread canary in the TLS block.\n\nWith   the   latter    choice    the    options    -mstack-protector-guard-reg=reg    and\n-mstack-protector-guard-offset=offset  furthermore  specify which register to use as base\nregister for reading the canary, and from what offset from that base register.  There  is\nno default register or offset as this is entirely for use within the Linux kernel.\n\nRL78 Options\n"
                },
                {
                    "name": "-msim",
                    "content": "Links in additional target libraries to support operation within a simulator.\n"
                },
                {
                    "name": "-mmul=none",
                    "content": ""
                },
                {
                    "name": "-mmul=g10",
                    "content": ""
                },
                {
                    "name": "-mmul=g13",
                    "content": ""
                },
                {
                    "name": "-mmul=g14",
                    "content": ""
                },
                {
                    "name": "-mmul=rl78",
                    "content": "Specifies  the  type  of  hardware  multiplication  and division support to be used.  The\nsimplest is \"none\", which uses software for both multiplication and  division.   This  is\nthe default.  The \"g13\" value is for the hardware multiply/divide peripheral found on the\nRL78/G13  (S2  core)  targets.  The \"g14\" value selects the use of the multiplication and\ndivision instructions supported by the RL78/G14 (S3 core) parts.  The value \"rl78\" is  an\nalias for \"g14\" and the value \"mg10\" is an alias for \"none\".\n\nIn  addition  a  C  preprocessor macro is defined, based upon the setting of this option.\nPossible values are: \"RL78MULNONE\", \"RL78MULG13\" or \"RL78MULG14\".\n"
                },
                {
                    "name": "-mcpu=g10",
                    "content": ""
                },
                {
                    "name": "-mcpu=g13",
                    "content": ""
                },
                {
                    "name": "-mcpu=g14",
                    "content": ""
                },
                {
                    "name": "-mcpu=rl78",
                    "content": "Specifies the RL78 core to target.  The default is the G14 core, also known as an S3 core\nor just RL78.  The G13 or S2 core does not have multiply or divide instructions,  instead\nit  uses  a  hardware  peripheral for these operations.  The G10 or S1 core does not have\nregister banks, so it uses a different calling convention.\n\nIf this option is set it also selects the type  of  hardware  multiply  support  to  use,\nunless  this  is  overridden  by an explicit -mmul=none option on the command line.  Thus\nspecifying -mcpu=g13 enables  the  use  of  the  G13  hardware  multiply  peripheral  and\nspecifying -mcpu=g10 disables the use of hardware multiplications altogether.\n\nNote,  although  the  RL78/G14  core  is  the  default  target,  specifying  -mcpu=g14 or\n-mcpu=rl78 on the command line does change the behavior of the toolchain  since  it  also\nenables G14 hardware multiply support.  If these options are not specified on the command\nline  then software multiplication routines will be used even though the code targets the\nRL78 core.  This is for backwards compatibility with older toolchains which did not  have\nhardware multiply and divide support.\n\nIn  addition  a  C  preprocessor macro is defined, based upon the setting of this option.\nPossible values are: \"RL78G10\", \"RL78G13\" or \"RL78G14\".\n"
                },
                {
                    "name": "-mg10",
                    "content": ""
                },
                {
                    "name": "-mg13",
                    "content": ""
                },
                {
                    "name": "-mg14",
                    "content": ""
                },
                {
                    "name": "-mrl78",
                    "content": "These are aliases for the corresponding -mcpu= option.  They are provided  for  backwards\ncompatibility.\n"
                },
                {
                    "name": "-mallregs",
                    "content": "Allow  the  compiler  to  use  all  of  the  available  registers.   By default registers\n\"r24..r31\" are reserved for use in interrupt handlers.  With this  option  enabled  these\nregisters can be used in ordinary functions as well.\n"
                },
                {
                    "name": "-m64bit-doubles",
                    "content": ""
                },
                {
                    "name": "-m32bit-doubles",
                    "content": "Make  the \"double\" data type be 64 bits (-m64bit-doubles) or 32 bits (-m32bit-doubles) in\nsize.  The default is -m32bit-doubles.\n"
                },
                {
                    "name": "-msave-mduc-in-interrupts",
                    "content": ""
                },
                {
                    "name": "-mno-save-mduc-in-interrupts",
                    "content": "Specifies that interrupt handler functions should preserve the MDUC registers.   This  is\nonly  necessary  if  normal  code  might  use  the MDUC registers, for example because it\nperforms multiplication and division operations.  The  default  is  to  ignore  the  MDUC\nregisters  as this makes the interrupt handlers faster.  The target option -mg13 needs to\nbe passed for this to work as this feature is only available on the G13 target (S2 core).\nThe MDUC registers will only be saved if the interrupt handler performs a  multiplication\nor division operation or it calls another function.\n\nIBM RS/6000 and PowerPC Options\n\nThese -m options are defined for the IBM RS/6000 and PowerPC:\n"
                },
                {
                    "name": "-mpowerpc-gpopt",
                    "content": ""
                },
                {
                    "name": "-mno-powerpc-gpopt",
                    "content": ""
                },
                {
                    "name": "-mpowerpc-gfxopt",
                    "content": ""
                },
                {
                    "name": "-mno-powerpc-gfxopt",
                    "content": ""
                },
                {
                    "name": "-mpowerpc64",
                    "content": ""
                },
                {
                    "name": "-mno-powerpc64",
                    "content": ""
                },
                {
                    "name": "-mmfcrf",
                    "content": ""
                },
                {
                    "name": "-mno-mfcrf",
                    "content": ""
                },
                {
                    "name": "-mpopcntb",
                    "content": ""
                },
                {
                    "name": "-mno-popcntb",
                    "content": ""
                },
                {
                    "name": "-mpopcntd",
                    "content": ""
                },
                {
                    "name": "-mno-popcntd",
                    "content": ""
                },
                {
                    "name": "-mfprnd",
                    "content": ""
                },
                {
                    "name": "-mno-fprnd",
                    "content": ""
                },
                {
                    "name": "-mcmpb",
                    "content": ""
                },
                {
                    "name": "-mno-cmpb",
                    "content": ""
                },
                {
                    "name": "-mhard-dfp",
                    "content": ""
                },
                {
                    "name": "-mno-hard-dfp",
                    "content": "You  use  these  options to specify which instructions are available on the processor you\nare using.  The default value of  these  options  is  determined  when  configuring  GCC.\nSpecifying the -mcpu=cputype overrides the specification of these options.  We recommend\nyou use the -mcpu=cputype option rather than the options listed above.\n\nSpecifying   -mpowerpc-gpopt   allows  GCC  to  use  the  optional  PowerPC  architecture\ninstructions  in  the  General  Purpose  group,  including  floating-point  square  root.\nSpecifying   -mpowerpc-gfxopt  allows  GCC  to  use  the  optional  PowerPC  architecture\ninstructions in the Graphics group, including floating-point select.\n\nThe -mmfcrf option allows  GCC  to  generate  the  move  from  condition  register  field\ninstruction  implemented  on  the  POWER4 processor and other processors that support the\nPowerPC V2.01 architecture.  The -mpopcntb option allows GCC to generate the popcount and\ndouble-precision FP reciprocal estimate instruction implemented on the  POWER5  processor\nand  other  processors that support the PowerPC V2.02 architecture.  The -mpopcntd option\nallows GCC to generate the popcount instruction implemented on the POWER7  processor  and\nother  processors that support the PowerPC V2.06 architecture.  The -mfprnd option allows\nGCC to generate the FP round to integer instructions implemented on the POWER5+ processor\nand other processors that support the PowerPC  V2.03  architecture.   The  -mcmpb  option\nallows  GCC to generate the compare bytes instruction implemented on the POWER6 processor\nand other processors that support the PowerPC V2.05 architecture.  The -mhard-dfp  option\nallows  GCC to generate the decimal floating-point instructions implemented on some POWER\nprocessors.\n\nThe -mpowerpc64 option allows GCC to generate the additional 64-bit instructions that are\nfound in the full  PowerPC64  architecture  and  to  treat  GPRs  as  64-bit,  doubleword\nquantities.  GCC defaults to -mno-powerpc64.\n"
                },
                {
                    "name": "-mcpu=_",
                    "content": "Set  architecture type, register usage, and instruction scheduling parameters for machine\ntype cputype.  Supported values for cputype are 401, 403, 405, 405fp, 440, 440fp,  464,\n464fp,  476,  476fp, 505, 601, 602, 603, 603e, 604, 604e, 620, 630, 740, 7400, 7450, 750,\n801, 821, 823, 860, 970, 8540,  a2,  e300c2,  e300c3,  e500mc,  e500mc64,  e5500,  e6500,\nec603e,  G3,  G4,  G5,  titan,  power3, power4, power5, power5+, power6, power6x, power7,\npower8, power9, power10, powerpc, powerpc64, powerpc64le, rs64, and native.\n\n-mcpu=powerpc, -mcpu=powerpc64, and -mcpu=powerpc64le specify pure 32-bit PowerPC (either\nendian), 64-bit big endian PowerPC and 64-bit little endian PowerPC architecture  machine\ntypes, with an appropriate, generic processor model assumed for scheduling purposes.\n\nSpecifying  native  as  cpu  type  detects  and  selects  the  architecture  option  that\ncorresponds to the host processor of the system performing the compilation.  -mcpu=native\nhas no effect if GCC does not recognize the processor.\n\nThe other options specify a specific processor.  Code generated under those options  runs\nbest on that processor, and may not run at all on others.\n\nThe -mcpu options automatically enable or disable the following options:\n\n-maltivec   -mfprnd   -mhard-float  -mmfcrf  -mmultiple -mpopcntb  -mpopcntd  -mpowerpc64\n-mpowerpc-gpopt  -mpowerpc-gfxopt  -mmulhw   -mdlmzb   -mmfpgpr   -mvsx  -mcrypto   -mhtm\n-mpower8-fusion     -mpower8-vector   -mquad-memory    -mquad-memory-atomic    -mfloat128\n-mfloat128-hardware -mprefixed -mpcrel -mmma -mrop-protect\n\nThe particular options set for any  particular  CPU  varies  between  compiler  versions,\ndepending  on  what  setting  seems  to  produce  optimal  code  for that CPU; it doesn't\nnecessarily reflect the actual hardware's capabilities.  If you wish to set an individual\noption to a particular value, you may specify it after the -mcpu option,  like  -mcpu=970\n-mno-altivec.\n\nOn  AIX,  the  -maltivec and -mpowerpc64 options are not enabled or disabled by the -mcpu\noption at present because AIX does not have full support  for  these  options.   You  may\nstill enable or disable them individually if you're sure it'll work in your environment.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "Set  the  instruction scheduling parameters for machine type cputype, but do not set the\narchitecture type or register  usage,  as  -mcpu=cputype  does.   The  same  values  for\ncputype  are  used  for  -mtune as for -mcpu.  If both are specified, the code generated\nuses the architecture and registers set by -mcpu, but the scheduling  parameters  set  by\n-mtune.\n"
                },
                {
                    "name": "-mcmodel=small",
                    "content": "Generate PowerPC64 code for the small model: The TOC is limited to 64k.\n"
                },
                {
                    "name": "-mcmodel=medium",
                    "content": "Generate  PowerPC64 code for the medium model: The TOC and other static data may be up to\na total of 4G in size.  This is the default for 64-bit Linux.\n"
                },
                {
                    "name": "-mcmodel=large",
                    "content": "Generate PowerPC64 code for the large model: The TOC may be up to 4G in size.  Other data\nand code is only limited by the 64-bit address space.\n"
                },
                {
                    "name": "-maltivec",
                    "content": ""
                },
                {
                    "name": "-mno-altivec",
                    "content": "Generate code that uses (does not use) AltiVec instructions, and also enable the  use  of\nbuilt-in functions that allow more direct access to the AltiVec instruction set.  You may\nalso need to set -mabi=altivec to adjust the current ABI with AltiVec ABI enhancements.\n\nWhen  -maltivec  is  used,  the element order for AltiVec intrinsics such as \"vecsplat\",\n\"vecextract\", and \"vecinsert\" match array element order corresponding to the endianness\nof the target.  That is, element  zero  identifies  the  leftmost  element  in  a  vector\nregister  when targeting a big-endian platform, and identifies the rightmost element in a\nvector register when targeting a little-endian platform.\n"
                },
                {
                    "name": "-mvrsave",
                    "content": ""
                },
                {
                    "name": "-mno-vrsave",
                    "content": "Generate VRSAVE instructions when generating AltiVec code.\n"
                },
                {
                    "name": "-msecure-plt",
                    "content": "Generate code that allows ld and ld.so to build executables  and  shared  libraries  with\nnon-executable \".plt\" and \".got\" sections.  This is a PowerPC 32-bit SYSV ABI option.\n"
                },
                {
                    "name": "-mbss-plt",
                    "content": "Generate code that uses a BSS \".plt\" section that ld.so fills in, and requires \".plt\" and\n\".got\" sections that are both writable and executable.  This is a PowerPC 32-bit SYSV ABI\noption.\n"
                },
                {
                    "name": "-misel",
                    "content": ""
                },
                {
                    "name": "-mno-isel",
                    "content": "This switch enables or disables the generation of ISEL instructions.\n"
                },
                {
                    "name": "-mvsx",
                    "content": ""
                },
                {
                    "name": "-mno-vsx",
                    "content": "Generate  code that uses (does not use) vector/scalar (VSX) instructions, and also enable\nthe use of built-in functions that allow more direct access to the VSX instruction set.\n"
                },
                {
                    "name": "-mcrypto",
                    "content": ""
                },
                {
                    "name": "-mno-crypto",
                    "content": "Enable the use (disable) of the built-in  functions  that  allow  direct  access  to  the\ncryptographic instructions that were added in version 2.07 of the PowerPC ISA.\n"
                },
                {
                    "name": "-mhtm",
                    "content": ""
                },
                {
                    "name": "-mno-htm",
                    "content": "Enable  (disable)  the  use  of  the  built-in  functions that allow direct access to the\nHardware Transactional Memory (HTM) instructions that were added in version 2.07  of  the\nPowerPC ISA.\n"
                },
                {
                    "name": "-mpower8-fusion",
                    "content": ""
                },
                {
                    "name": "-mno-power8-fusion",
                    "content": "Generate  code  that  keeps (does not keeps) some integer operations adjacent so that the\ninstructions can be fused together on power8 and later processors.\n"
                },
                {
                    "name": "-mpower8-vector",
                    "content": ""
                },
                {
                    "name": "-mno-power8-vector",
                    "content": "Generate code that uses (does not use) the vector and scalar instructions that were added\nin version 2.07 of the PowerPC ISA.  Also enable the use of built-in functions that allow\nmore direct access to the vector instructions.\n"
                },
                {
                    "name": "-mquad-memory",
                    "content": ""
                },
                {
                    "name": "-mno-quad-memory",
                    "content": "Generate code that uses (does not use) the non-atomic quad word memory instructions.  The\n-mquad-memory option requires use of 64-bit mode.\n"
                },
                {
                    "name": "-mquad-memory-atomic",
                    "content": ""
                },
                {
                    "name": "-mno-quad-memory-atomic",
                    "content": "Generate code that uses (does not use) the atomic quad  word  memory  instructions.   The\n-mquad-memory-atomic option requires use of 64-bit mode.\n"
                },
                {
                    "name": "-mfloat128",
                    "content": ""
                },
                {
                    "name": "-mno-float128",
                    "content": "Enable/disable  the  float128  keyword  for  IEEE 128-bit floating point and use either\nsoftware emulation for IEEE 128-bit floating point or hardware instructions.\n\nThe VSX instruction set (-mvsx) must be enabled to use the IEEE  128-bit  floating  point\nsupport.  The IEEE 128-bit floating point is only supported on Linux.\n\nThe  default for -mfloat128 is enabled on PowerPC Linux systems using the VSX instruction\nset, and disabled on other systems.\n\nIf you use the ISA 3.0 instruction set (-mpower9-vector  or  -mcpu=power9)  on  a  64-bit\nsystem,  the  IEEE  128-bit floating point support will also enable the generation of ISA\n3.0 IEEE 128-bit floating point instructions.   Otherwise,  if  you  do  not  specify  to\ngenerate  ISA  3.0  instructions  or  you  are targeting a 32-bit big endian system, IEEE\n128-bit floating point will be done with software emulation.\n"
                },
                {
                    "name": "-mfloat128-hardware",
                    "content": ""
                },
                {
                    "name": "-mno-float128-hardware",
                    "content": "Enable/disable using ISA 3.0 hardware instructions to support the float128 data type.\n\nThe default for -mfloat128-hardware is enabled on PowerPC Linux systems using the ISA 3.0\ninstruction set, and disabled on other systems.\n"
                },
                {
                    "name": "-m32",
                    "content": ""
                },
                {
                    "name": "-m64",
                    "content": "Generate code for 32-bit or 64-bit environments of Darwin  and  SVR4  targets  (including\nGNU/Linux).   The  32-bit environment sets int, long and pointer to 32 bits and generates\ncode that runs on any PowerPC variant.  The 64-bit environment sets int to  32  bits  and\nlong and pointer to 64 bits, and generates code for PowerPC64, as for -mpowerpc64.\n"
                },
                {
                    "name": "-mfull-toc",
                    "content": ""
                },
                {
                    "name": "-mno-fp-in-toc",
                    "content": ""
                },
                {
                    "name": "-mno-sum-in-toc",
                    "content": ""
                },
                {
                    "name": "-mminimal-toc",
                    "content": "Modify  generation  of the TOC (Table Of Contents), which is created for every executable\nfile.  The -mfull-toc option is selected by default.  In  that  case,  GCC  allocates  at\nleast  one  TOC  entry  for each unique non-automatic variable reference in your program.\nGCC also places floating-point constants in the TOC.  However, only  16,384  entries  are\navailable in the TOC.\n\nIf  you  receive a linker error message that saying you have overflowed the available TOC\nspace, you can  reduce  the  amount  of  TOC  space  used  with  the  -mno-fp-in-toc  and\n-mno-sum-in-toc   options.   -mno-fp-in-toc  prevents  GCC  from  putting  floating-point\nconstants in the TOC and -mno-sum-in-toc forces GCC to generate code to calculate the sum\nof an address and a constant at run time instead of putting that sum into the  TOC.   You\nmay  specify  one  or  both  of  these options.  Each causes GCC to produce very slightly\nslower and larger code at the expense of conserving TOC space.\n\nIf you still run out of space in the TOC even when you specify  both  of  these  options,\nspecify  -mminimal-toc  instead.   This  option causes GCC to make only one TOC entry for\nevery file.  When you specify this option, GCC produces code that is  slower  and  larger\nbut which uses extremely little TOC space.  You may wish to use this option only on files\nthat contain less frequently-executed code.\n"
                },
                {
                    "name": "-maix64",
                    "content": ""
                },
                {
                    "name": "-maix32",
                    "content": "Enable  64-bit  AIX  ABI and calling convention: 64-bit pointers, 64-bit \"long\" type, and\nthe infrastructure needed to support them.  Specifying -maix64 implies -mpowerpc64, while\n-maix32 disables the 64-bit ABI and implies -mno-powerpc64.  GCC defaults to -maix32.\n"
                },
                {
                    "name": "-mxl-compat",
                    "content": ""
                },
                {
                    "name": "-mno-xl-compat",
                    "content": "Produce code that conforms more closely to IBM XL  compiler  semantics  when  using  AIX-\ncompatible  ABI.   Pass  floating-point  arguments  to  prototyped  functions  beyond the\nregister save area (RSA) on the stack in addition to argument FPRs.  Do not  assume  that\nmost  significant  double in 128-bit long double value is properly rounded when comparing\nvalues and converting to double.  Use XL symbol names for long double support routines.\n\nThe AIX calling convention was extended but not initially documented to handle an obscure\nK&R C case of calling a function that takes the  address  of  its  arguments  with  fewer\narguments  than  declared.   IBM XL compilers access floating-point arguments that do not\nfit in the RSA from the  stack  when  a  subroutine  is  compiled  without  optimization.\nBecause  always  storing  floating-point arguments on the stack is inefficient and rarely\nneeded, this option is not  enabled  by  default  and  only  is  necessary  when  calling\nsubroutines compiled by IBM XL compilers without optimization.\n"
                },
                {
                    "name": "-mpe",
                    "content": "Support  IBM  RS/6000  SP  Parallel Environment (PE).  Link an application written to use\nmessage passing with special startup code to enable the application to run.   The  system\nmust  have  PE  installed in the standard location (/usr/lpp/ppe.poe/), or the specs file\nmust be overridden with the -specs= option to specify the appropriate directory location.\nThe Parallel Environment does not support threads, so the -mpe option  and  the  -pthread\noption are incompatible.\n"
                },
                {
                    "name": "-malign-natural",
                    "content": ""
                },
                {
                    "name": "-malign-power",
                    "content": "On AIX, 32-bit Darwin, and 64-bit PowerPC GNU/Linux, the option -malign-natural overrides\nthe  ABI-defined  alignment  of  larger  types,  such as floating-point doubles, on their\nnatural size-based boundary.  The option -malign-power instructs GCC to follow  the  ABI-\nspecified alignment rules.  GCC defaults to the standard alignment defined in the ABI.\n\nOn 64-bit Darwin, natural alignment is the default, and -malign-power is not supported.\n"
                },
                {
                    "name": "-msoft-float",
                    "content": ""
                },
                {
                    "name": "-mhard-float",
                    "content": "Generate  code  that  does  not  use  (uses)  the  floating-point register set.  Software\nfloating-point emulation is provided if you use the -msoft-float  option,  and  pass  the\noption to GCC when linking.\n"
                },
                {
                    "name": "-mmultiple",
                    "content": ""
                },
                {
                    "name": "-mno-multiple",
                    "content": "Generate  code that uses (does not use) the load multiple word instructions and the store\nmultiple word instructions.   These  instructions  are  generated  by  default  on  POWER\nsystems,  and  not  generated on PowerPC systems.  Do not use -mmultiple on little-endian\nPowerPC systems, since those instructions do not work when the processor  is  in  little-\nendian  mode.   The  exceptions  are PPC740 and PPC750 which permit these instructions in\nlittle-endian mode.\n"
                },
                {
                    "name": "-mupdate",
                    "content": ""
                },
                {
                    "name": "-mno-update",
                    "content": "Generate code that uses (does not use) the load or store  instructions  that  update  the\nbase  register  to the address of the calculated memory location.  These instructions are\ngenerated by default.  If you use -mno-update, there is a small window between  the  time\nthat  the stack pointer is updated and the address of the previous frame is stored, which\nmeans code that walks the stack frame across interrupts  or  signals  may  get  corrupted\ndata.\n"
                },
                {
                    "name": "-mavoid-indexed-addresses",
                    "content": ""
                },
                {
                    "name": "-mno-avoid-indexed-addresses",
                    "content": "Generate  code  that  tries  to  avoid  (not  avoid)  the  use  of  indexed load or store\ninstructions. These instructions can incur a performance penalty on Power6 processors  in\ncertain situations, such as when stepping through large arrays that cross a 16M boundary.\nThis option is enabled by default when targeting Power6 and disabled otherwise.\n"
                },
                {
                    "name": "-mfused-madd",
                    "content": ""
                },
                {
                    "name": "-mno-fused-madd",
                    "content": "Generate  code  that  uses  (does  not  use)  the  floating-point multiply and accumulate\ninstructions.  These instructions are generated by default if hardware floating point  is\nused.  The machine-dependent -mfused-madd option is now mapped to the machine-independent\n-ffp-contract=fast option, and -mno-fused-madd is mapped to -ffp-contract=off.\n"
                },
                {
                    "name": "-mmulhw",
                    "content": ""
                },
                {
                    "name": "-mno-mulhw",
                    "content": "Generate  code  that  uses  (does not use) the half-word multiply and multiply-accumulate\ninstructions on the IBM 405,  440,  464  and  476  processors.   These  instructions  are\ngenerated by default when targeting those processors.\n"
                },
                {
                    "name": "-mdlmzb",
                    "content": ""
                },
                {
                    "name": "-mno-dlmzb",
                    "content": "Generate  code  that  uses  (does not use) the string-search dlmzb instruction on the IBM\n405, 440, 464 and  476  processors.   This  instruction  is  generated  by  default  when\ntargeting those processors.\n"
                },
                {
                    "name": "-mno-bit-align",
                    "content": ""
                },
                {
                    "name": "-mbit-align",
                    "content": "On  System  V.4 and embedded PowerPC systems do not (do) force structures and unions that\ncontain bit-fields to be aligned to the base type of the bit-field.\n\nFor example, by default a structure containing nothing but  8  \"unsigned\"  bit-fields  of\nlength  1  is  aligned  to  a  4-byte  boundary  and  has  a  size  of 4 bytes.  By using\n-mno-bit-align, the structure is aligned to a 1-byte boundary and is 1 byte in size.\n"
                },
                {
                    "name": "-mno-strict-align",
                    "content": ""
                },
                {
                    "name": "-mstrict-align",
                    "content": "On System V.4 and embedded PowerPC systems do  not  (do)  assume  that  unaligned  memory\nreferences are handled by the system.\n"
                },
                {
                    "name": "-mrelocatable",
                    "content": ""
                },
                {
                    "name": "-mno-relocatable",
                    "content": "Generate  code  that  allows  (does  not  allow) a static executable to be relocated to a\ndifferent address at run time.  A simple embedded PowerPC system loader  should  relocate\nthe  entire  contents  of  \".got2\" and 4-byte locations listed in the \".fixup\" section, a\ntable of 32-bit addresses generated by this option.  For this to work, all objects linked\ntogether must be compiled with -mrelocatable or  -mrelocatable-lib.   -mrelocatable  code\naligns the stack to an 8-byte boundary.\n"
                },
                {
                    "name": "-mrelocatable-lib",
                    "content": ""
                },
                {
                    "name": "-mno-relocatable-lib",
                    "content": "Like  -mrelocatable,  -mrelocatable-lib  generates  a  \".fixup\"  section  to allow static\nexecutables to be relocated at run time, but -mrelocatable-lib does not use  the  smaller\nstack  alignment of -mrelocatable.  Objects compiled with -mrelocatable-lib may be linked\nwith objects compiled with any combination of the -mrelocatable options.\n"
                },
                {
                    "name": "-mno-toc",
                    "content": ""
                },
                {
                    "name": "-mtoc",
                    "content": "On System V.4 and embedded PowerPC systems do not (do) assume that register 2 contains  a\npointer to a global area pointing to the addresses used in the program.\n"
                },
                {
                    "name": "-mlittle",
                    "content": ""
                },
                {
                    "name": "-mlittle-endian",
                    "content": "On  System  V.4  and  embedded  PowerPC systems compile code for the processor in little-\nendian mode.  The -mlittle-endian option is the same as -mlittle.\n"
                },
                {
                    "name": "-mbig",
                    "content": ""
                },
                {
                    "name": "-mbig-endian",
                    "content": "On System V.4 and embedded PowerPC systems compile code for the processor  in  big-endian\nmode.  The -mbig-endian option is the same as -mbig.\n"
                },
                {
                    "name": "-mdynamic-no-pic",
                    "content": "On  Darwin and Mac OS X systems, compile code so that it is not relocatable, but that its\nexternal references are relocatable.  The resulting code is  suitable  for  applications,\nbut not shared libraries.\n"
                },
                {
                    "name": "-msingle-pic-base",
                    "content": "Treat  the  register  used for PIC addressing as read-only, rather than loading it in the\nprologue for each function.  The runtime system  is  responsible  for  initializing  this\nregister with an appropriate value before execution begins.\n"
                },
                {
                    "name": "-mprioritize-restricted-insns=_",
                    "content": "This   option  controls  the  priority  that  is  assigned  to  dispatch-slot  restricted\ninstructions during the second scheduling pass.  The argument priority takes the value 0,\n1, or 2 to assign no, highest, or second-highest (respectively) priority to dispatch-slot\nrestricted instructions.\n"
                },
                {
                    "name": "-msched-costly-dep=_",
                    "content": "This option controls which  dependences  are  considered  costly  by  the  target  during\ninstruction scheduling.  The argument dependencetype takes one of the following values:\n\nno  No dependence is costly.\n\nall All dependences are costly.\n\ntruestoretoload\nA true dependence from store to load is costly.\n\nstoretoload\nAny dependence from store to load is costly.\n\nnumber\nAny dependence for which the latency is greater than or equal to number is costly.\n"
                },
                {
                    "name": "-minsert-sched-nops=_",
                    "content": "This  option  controls  which  NOP  insertion scheme is used during the second scheduling\npass.  The argument scheme takes one of the following values:\n\nno  Don't insert NOPs.\n\npad Pad with NOPs any dispatch group that  has  vacant  issue  slots,  according  to  the\nscheduler's grouping.\n\nregroupexact\nInsert  NOPs to force costly dependent insns into separate groups.  Insert exactly as\nmany NOPs as needed to force an insn to a  new  group,  according  to  the  estimated\nprocessor grouping.\n\nnumber\nInsert NOPs to force costly dependent insns into separate groups.  Insert number NOPs\nto force an insn to a new group.\n"
                },
                {
                    "name": "-mcall-sysv",
                    "content": "On  System  V.4  and embedded PowerPC systems compile code using calling conventions that\nadhere to the March 1995 draft of the System  V  Application  Binary  Interface,  PowerPC\nprocessor   supplement.    This   is   the   default  unless  you  configured  GCC  using\npowerpc-*-eabiaix.\n"
                },
                {
                    "name": "-mcall-sysv-eabi",
                    "content": ""
                },
                {
                    "name": "-mcall-eabi",
                    "content": "Specify both -mcall-sysv and -meabi options.\n"
                },
                {
                    "name": "-mcall-sysv-noeabi",
                    "content": "Specify both -mcall-sysv and -mno-eabi options.\n"
                },
                {
                    "name": "-mcall-aixdesc",
                    "content": "On System V.4 and embedded PowerPC systems compile code for the AIX operating system.\n"
                },
                {
                    "name": "-mcall-linux",
                    "content": "On System V.4 and embedded PowerPC systems compile code for the Linux-based GNU system.\n"
                },
                {
                    "name": "-mcall-freebsd",
                    "content": "On System V.4 and embedded PowerPC systems compile code for the FreeBSD operating system.\n"
                },
                {
                    "name": "-mcall-netbsd",
                    "content": "On System V.4 and embedded PowerPC systems compile code for the NetBSD operating system.\n"
                },
                {
                    "name": "-mcall-openbsd",
                    "content": "On System V.4 and embedded PowerPC systems compile code for the OpenBSD operating system.\n"
                },
                {
                    "name": "-mtraceback=_",
                    "content": "Select the type of traceback table. Valid values for tracebacktype are full,  part,  and\nno.\n"
                },
                {
                    "name": "-maix-struct-return",
                    "content": "Return all structures in memory (as specified by the AIX ABI).\n"
                },
                {
                    "name": "-msvr4-struct-return",
                    "content": "Return structures smaller than 8 bytes in registers (as specified by the SVR4 ABI).\n"
                },
                {
                    "name": "-mabi=_",
                    "content": "Extend  the  current  ABI  with  a particular extension, or remove such extension.  Valid\nvalues are: altivec, no-altivec, ibmlongdouble, ieeelongdouble,  elfv1,  elfv2,  and  for\nAIX: vec-extabi, vec-default.\n"
                },
                {
                    "name": "-mabi=ibmlongdouble",
                    "content": "Change  the current ABI to use IBM extended-precision long double.  This is not likely to\nwork if your system defaults to using IEEE extended-precision long double.  If you change\nthe long double type from IEEE extended-precision, the  compiler  will  issue  a  warning\nunless you use the -Wno-psabi option.  Requires -mlong-double-128 to be enabled.\n"
                },
                {
                    "name": "-mabi=ieeelongdouble",
                    "content": "Change the current ABI to use IEEE extended-precision long double.  This is not likely to\nwork  if your system defaults to using IBM extended-precision long double.  If you change\nthe long double type from IBM extended-precision,  the  compiler  will  issue  a  warning\nunless you use the -Wno-psabi option.  Requires -mlong-double-128 to be enabled.\n"
                },
                {
                    "name": "-mabi=elfv1",
                    "content": "Change  the  current  ABI  to  use the ELFv1 ABI.  This is the default ABI for big-endian\nPowerPC 64-bit Linux.  Overriding the default ABI requires special system support and  is\nlikely to fail in spectacular ways.\n"
                },
                {
                    "name": "-mabi=elfv2",
                    "content": "Change  the  current ABI to use the ELFv2 ABI.  This is the default ABI for little-endian\nPowerPC 64-bit Linux.  Overriding the default ABI requires special system support and  is\nlikely to fail in spectacular ways.\n"
                },
                {
                    "name": "-mgnu-attribute",
                    "content": ""
                },
                {
                    "name": "-mno-gnu-attribute",
                    "content": "Emit  .gnuattribute  assembly  directives  to  set  tag/value pairs in a .gnu.attributes\nsection that specify ABI variations in function parameters or return values.\n"
                },
                {
                    "name": "-mprototype",
                    "content": ""
                },
                {
                    "name": "-mno-prototype",
                    "content": "On System V.4 and embedded PowerPC systems assume that all  calls  to  variable  argument\nfunctions  are  properly  prototyped.  Otherwise, the compiler must insert an instruction\nbefore every non-prototyped call to set or clear bit 6 of  the  condition  code  register\n(\"CR\")  to  indicate  whether  floating-point  values  are  passed  in the floating-point\nregisters in case the function takes variable arguments.  With -mprototype, only calls to\nprototyped variable argument functions set or clear the bit.\n"
                },
                {
                    "name": "-msim",
                    "content": "On embedded PowerPC systems, assume that the startup module is called sim-crt0.o and that\nthe  standard  C  libraries  are  libsim.a  and  libc.a.   This  is   the   default   for\npowerpc-*-eabisim configurations.\n"
                },
                {
                    "name": "-mmvme",
                    "content": "On  embedded  PowerPC  systems,  assume  that the startup module is called crt0.o and the\nstandard C libraries are libmvme.a and libc.a.\n"
                },
                {
                    "name": "-mads",
                    "content": "On embedded PowerPC systems, assume that the startup module  is  called  crt0.o  and  the\nstandard C libraries are libads.a and libc.a.\n"
                },
                {
                    "name": "-myellowknife",
                    "content": "On  embedded  PowerPC  systems,  assume  that the startup module is called crt0.o and the\nstandard C libraries are libyk.a and libc.a.\n"
                },
                {
                    "name": "-mvxworks",
                    "content": "On System V.4 and embedded PowerPC systems, specify that you are compiling for a  VxWorks\nsystem.\n"
                },
                {
                    "name": "-memb",
                    "content": "On  embedded  PowerPC  systems, set the \"PPCEMB\" bit in the ELF flags header to indicate\nthat eabi extended relocations are used.\n"
                },
                {
                    "name": "-meabi",
                    "content": ""
                },
                {
                    "name": "-mno-eabi",
                    "content": "On System  V.4  and  embedded  PowerPC  systems  do  (do  not)  adhere  to  the  Embedded\nApplications  Binary  Interface (EABI), which is a set of modifications to the System V.4\nspecifications.  Selecting -meabi means that the stack is aligned to an 8-byte  boundary,\na function \"eabi\" is called from \"main\" to set up the EABI environment, and the -msdata\noption  can use both \"r2\" and \"r13\" to point to two separate small data areas.  Selecting\n-mno-eabi means that the stack is aligned to a 16-byte boundary, no  EABI  initialization\nfunction  is  called  from  \"main\",  and the -msdata option only uses \"r13\" to point to a\nsingle small data area.  The -meabi option is on by default if you configured  GCC  using\none of the powerpc*-*-eabi* options.\n"
                },
                {
                    "name": "-msdata=eabi",
                    "content": "On  System  V.4  and  embedded  PowerPC systems, put small initialized \"const\" global and\nstatic data in the \".sdata2\" section, which is pointed to by register  \"r2\".   Put  small\ninitialized  non-\"const\" global and static data in the \".sdata\" section, which is pointed\nto by register \"r13\".  Put small uninitialized global and  static  data  in  the  \".sbss\"\nsection,  which  is  adjacent  to  the  \".sdata\"  section.   The  -msdata=eabi  option is\nincompatible with the -mrelocatable option.  The -msdata=eabi option also sets the  -memb\noption.\n"
                },
                {
                    "name": "-msdata=sysv",
                    "content": "On  System  V.4  and  embedded  PowerPC  systems, put small global and static data in the\n\".sdata\" section, which is pointed to by register \"r13\".  Put small uninitialized  global\nand  static  data in the \".sbss\" section, which is adjacent to the \".sdata\" section.  The\n-msdata=sysv option is incompatible with the -mrelocatable option.\n"
                },
                {
                    "name": "-msdata=default",
                    "content": ""
                },
                {
                    "name": "-msdata",
                    "content": "On System V.4 and embedded PowerPC systems, if -meabi is used, compile code the  same  as\n-msdata=eabi, otherwise compile code the same as -msdata=sysv.\n"
                },
                {
                    "name": "-msdata=data",
                    "content": "On  System  V.4  and  embedded  PowerPC  systems,  put  small global data in the \".sdata\"\nsection.  Put small uninitialized global  data  in  the  \".sbss\"  section.   Do  not  use\nregister  \"r13\" to address small data however.  This is the default behavior unless other\n-msdata options are used.\n"
                },
                {
                    "name": "-msdata=none",
                    "content": ""
                },
                {
                    "name": "-mno-sdata",
                    "content": "On embedded PowerPC systems, put all initialized global and static data  in  the  \".data\"\nsection, and all uninitialized data in the \".bss\" section.\n"
                },
                {
                    "name": "-mreadonly-in-sdata",
                    "content": "Put read-only objects in the \".sdata\" section as well.  This is the default.\n"
                },
                {
                    "name": "-mblock-move-inline-limit=_",
                    "content": "Inline all block moves (such as calls to \"memcpy\" or structure copies) less than or equal\nto  num  bytes.   The minimum value for num is 32 bytes on 32-bit targets and 64 bytes on\n64-bit targets.  The default value is target-specific.\n"
                },
                {
                    "name": "-mblock-compare-inline-limit=_",
                    "content": "Generate non-looping inline code for all block compares (such as  calls  to  \"memcmp\"  or\nstructure  compares)  less  than or equal to num bytes. If num is 0, all inline expansion\n(non-loop and loop) of block compare is disabled. The default value is target-specific.\n"
                },
                {
                    "name": "-mblock-compare-inline-loop-limit=_",
                    "content": "Generate an inline expansion using loop code for all block compares that are less than or\nequal to num bytes, but  greater  than  the  limit  for  non-loop  inline  block  compare\nexpansion. If the block length is not constant, at most num bytes will be compared before\n\"memcmp\"  is  called  to compare the remainder of the block. The default value is target-\nspecific.\n"
                },
                {
                    "name": "-mstring-compare-inline-limit=_",
                    "content": "Compare at most num string bytes with inline code.  If the difference or end of string is\nnot found at the end of the inline compare a call to \"strcmp\" or \"strncmp\" will take care\nof the rest of the comparison. The default is 64 bytes.\n"
                },
                {
                    "name": "-G _",
                    "content": "On embedded PowerPC systems, put global and static items less than or equal to num  bytes\ninto  the  small  data  or  BSS  sections  instead of the normal data or BSS section.  By\ndefault, num is 8.  The -G num switch is also passed to the linker.  All  modules  should\nbe compiled with the same -G num value.\n",
                    "flag": "-G"
                },
                {
                    "name": "-mregnames",
                    "content": ""
                },
                {
                    "name": "-mno-regnames",
                    "content": "On  System  V.4  and  embedded  PowerPC  systems  do  (do not) emit register names in the\nassembly language output using symbolic forms.\n"
                },
                {
                    "name": "-mlongcall",
                    "content": ""
                },
                {
                    "name": "-mno-longcall",
                    "content": "By default assume that all calls are far away so that a longer and more expensive calling\nsequence is required.  This is required for calls farther than 32  megabytes  (33,554,432\nbytes)  from  the  current location.  A short call is generated if the compiler knows the\ncall cannot be that far away.  This setting can be overridden by the \"shortcall\" function\nattribute, or by #pragma longcall(0).\n\nSome linkers are capable of detecting out-of-range calls and generating glue code on  the\nfly.   On these systems, long calls are unnecessary and generate slower code.  As of this\nwriting, the AIX linker can do this, as can the GNU linker for PowerPC/64.  It is planned\nto add this feature to the GNU linker for 32-bit PowerPC systems as well.\n\nOn PowerPC64 ELFv2 and 32-bit PowerPC systems with newer GNU linkers,  GCC  can  generate\nlong  calls using an inline PLT call sequence (see -mpltseq).  PowerPC with -mbss-plt and\nPowerPC64 ELFv1 (big-endian) do not support inline PLT calls.\n\nOn Darwin/PPC systems, \"#pragma longcall\" generates \"jbsr callee,  L42\",  plus  a  branch\nisland (glue code).  The two target addresses represent the callee and the branch island.\nThe  Darwin/PPC  linker  prefers the first address and generates a \"bl callee\" if the PPC\n\"bl\" instruction reaches the callee directly; otherwise, the linker generates \"bl L42\" to\ncall the branch island.  The branch island  is  appended  to  the  body  of  the  calling\nfunction; it computes the full 32-bit address of the callee and jumps to it.\n\nOn  Mach-O  (Darwin) systems, this option directs the compiler emit to the glue for every\ndirect call, and the Darwin linker decides whether to use or discard it.\n\nIn the future, GCC may ignore all longcall specifications when the  linker  is  known  to\ngenerate glue.\n"
                },
                {
                    "name": "-mpltseq",
                    "content": ""
                },
                {
                    "name": "-mno-pltseq",
                    "content": "Implement  (do  not  implement) -fno-plt and long calls using an inline PLT call sequence\nthat supports lazy linking and long calls to  functions  in  dlopen'd  shared  libraries.\nInline  PLT  calls  are only supported on PowerPC64 ELFv2 and 32-bit PowerPC systems with\nnewer GNU linkers, and are enabled by default if the support is detected when configuring\nGCC, and, in the case of 32-bit PowerPC, if GCC is  configured  with  --enable-secureplt.\n-mpltseq  code  and  -mbss-plt  32-bit  PowerPC  relocatable  objects  may  not be linked\ntogether.\n"
                },
                {
                    "name": "-mtls-markers",
                    "content": ""
                },
                {
                    "name": "-mno-tls-markers",
                    "content": "Mark (do not mark) calls to \"tlsgetaddr\" with a relocation  specifying  the  function\nargument.   The  relocation  allows  the  linker to reliably associate function call with\nargument setup instructions for TLS optimization, which in  turn  allows  GCC  to  better\nschedule the sequence.\n"
                },
                {
                    "name": "-mrecip",
                    "content": ""
                },
                {
                    "name": "-mno-recip",
                    "content": "This  option  enables  use of the reciprocal estimate and reciprocal square root estimate\ninstructions with additional Newton-Raphson steps to increase precision instead of  doing\na  divide  or  square  root  and divide for floating-point arguments.  You should use the\n-ffast-math  option  when  using  -mrecip  (or  at   least   -funsafe-math-optimizations,\n-ffinite-math-only,  -freciprocal-math  and  -fno-trapping-math).   Note  that  while the\nthroughput of the sequence is generally higher than the throughput of the  non-reciprocal\ninstruction,  the  precision  of  the  sequence can be decreased by up to 2 ulp (i.e. the\ninverse of 1.0 equals 0.99999994) for reciprocal square roots.\n"
                },
                {
                    "name": "-mrecip=_",
                    "content": "This option controls which reciprocal estimate instructions may be used.  opt is a comma-\nseparated list of options, which may be preceded by a \"!\" to invert the option:\n\nall Enable all estimate instructions.\n\ndefault\nEnable the default instructions, equivalent to -mrecip.\n\nnone\nDisable all estimate instructions, equivalent to -mno-recip.\n\ndiv Enable  the  reciprocal  approximation  instructions  for  both  single  and   double\nprecision.\n\ndivf\nEnable the single-precision reciprocal approximation instructions.\n\ndivd\nEnable the double-precision reciprocal approximation instructions.\n\nrsqrt\nEnable  the  reciprocal  square  root  approximation instructions for both single and\ndouble precision.\n\nrsqrtf\nEnable the single-precision reciprocal square root approximation instructions.\n\nrsqrtd\nEnable the double-precision reciprocal square root approximation instructions.\n\nSo, for example, -mrecip=all,!rsqrtd enables all of the reciprocal estimate instructions,\nexcept for the \"FRSQRTE\", \"XSRSQRTEDP\", and \"XVRSQRTEDP\" instructions  which  handle  the\ndouble-precision reciprocal square root calculations.\n"
                },
                {
                    "name": "-mrecip-precision",
                    "content": ""
                },
                {
                    "name": "-mno-recip-precision",
                    "content": "Assume (do not assume) that the reciprocal estimate instructions provide higher-precision\nestimates  than  is mandated by the PowerPC ABI.  Selecting -mcpu=power6, -mcpu=power7 or\n-mcpu=power8 automatically selects -mrecip-precision.  The double-precision  square  root\nestimate  instructions are not generated by default on low-precision machines, since they\ndo not provide an estimate that converges after three steps.\n"
                },
                {
                    "name": "-mveclibabi=_",
                    "content": "Specifies the ABI type to use for vectorizing intrinsics using an external library.   The\nonly  type  supported  at  present  is  mass,  which  specifies to use IBM's Mathematical\nAcceleration  Subsystem  (MASS)  libraries  for  vectorizing  intrinsics  using  external\nlibraries.   GCC  currently  emits  calls  to  \"acosd2\",  \"acosf4\", \"acoshd2\", \"acoshf4\",\n\"asind2\", \"asinf4\",  \"asinhd2\",  \"asinhf4\",  \"atan2d2\",  \"atan2f4\",  \"atand2\",  \"atanf4\",\n\"atanhd2\", \"atanhf4\", \"cbrtd2\", \"cbrtf4\", \"cosd2\", \"cosf4\", \"coshd2\", \"coshf4\", \"erfcd2\",\n\"erfcf4\",  \"erfd2\",  \"erff4\", \"exp2d2\", \"exp2f4\", \"expd2\", \"expf4\", \"expm1d2\", \"expm1f4\",\n\"hypotd2\", \"hypotf4\", \"lgammad2\", \"lgammaf4\", \"log10d2\", \"log10f4\", \"log1pd2\", \"log1pf4\",\n\"log2d2\", \"log2f4\", \"logd2\",  \"logf4\",  \"powd2\",  \"powf4\",  \"sind2\",  \"sinf4\",  \"sinhd2\",\n\"sinhf4\",  \"sqrtd2\",  \"sqrtf4\",  \"tand2\", \"tanf4\", \"tanhd2\", and \"tanhf4\" when generating\ncode for power7.  Both -ftree-vectorize  and  -funsafe-math-optimizations  must  also  be\nenabled.  The MASS libraries must be specified at link time.\n"
                },
                {
                    "name": "-mfriz",
                    "content": ""
                },
                {
                    "name": "-mno-friz",
                    "content": "Generate  (do  not  generate) the \"friz\" instruction when the -funsafe-math-optimizations\noption is used to optimize rounding of floating-point values to 64-bit integer  and  back\nto  floating  point.   The  \"friz\"  instruction  does  not  return  the same value if the\nfloating-point number is too large to fit in an integer.\n"
                },
                {
                    "name": "-mpointers-to-nested-functions",
                    "content": ""
                },
                {
                    "name": "-mno-pointers-to-nested-functions",
                    "content": "Generate (do not generate) code to load up the static chain register (\"r11\") when calling\nthrough a pointer on AIX and 64-bit Linux systems where a function pointer  points  to  a\n3-word  descriptor  giving the function address, TOC value to be loaded in register \"r2\",\nand    static    chain    value    to    be    loaded    in    register    \"r11\".     The\n-mpointers-to-nested-functions  is  on  by  default.  You cannot call through pointers to\nnested functions or pointers to functions compiled in other languages that use the static\nchain if you use -mno-pointers-to-nested-functions.\n"
                },
                {
                    "name": "-msave-toc-indirect",
                    "content": ""
                },
                {
                    "name": "-mno-save-toc-indirect",
                    "content": "Generate (do not generate) code to save the TOC value in the reserved stack  location  in\nthe  function  prologue  if  the function calls through a pointer on AIX and 64-bit Linux\nsystems.  If the TOC value is not saved in the prologue, it is saved just before the call\nthrough the pointer.  The -mno-save-toc-indirect option is the default.\n"
                },
                {
                    "name": "-mcompat-align-parm",
                    "content": ""
                },
                {
                    "name": "-mno-compat-align-parm",
                    "content": "Generate (do not generate) code to pass structure parameters with a maximum alignment  of\n64 bits, for compatibility with older versions of GCC.\n\nOlder versions of GCC (prior to 4.9.0) incorrectly did not align a structure parameter on\na  128-bit  boundary  when that structure contained a member requiring 128-bit alignment.\nThis is corrected in more recent versions of GCC.  This option may be  used  to  generate\ncode that is compatible with functions compiled with older versions of GCC.\n\nThe -mno-compat-align-parm option is the default.\n"
                },
                {
                    "name": "-mstack-protector-guard=_",
                    "content": ""
                },
                {
                    "name": "-mstack-protector-guard-reg=_",
                    "content": ""
                },
                {
                    "name": "-mstack-protector-guard-offset=_",
                    "content": ""
                },
                {
                    "name": "-mstack-protector-guard-symbol=_",
                    "content": "Generate stack protection code using canary at guard.  Supported locations are global for\nglobal  canary  or  tls for per-thread canary in the TLS block (the default with GNU libc\nversion 2.4 or later).\n\nWith   the   latter    choice    the    options    -mstack-protector-guard-reg=reg    and\n-mstack-protector-guard-offset=offset  furthermore  specify which register to use as base\nregister for reading the canary, and from  what  offset  from  that  base  register.  The\ndefault     for     those     is     as     specified     in     the     relevant    ABI.\n-mstack-protector-guard-symbol=symbol overrides the offset with a symbol reference  to  a\ncanary in the TLS block.\n"
                },
                {
                    "name": "-mpcrel",
                    "content": ""
                },
                {
                    "name": "-mno-pcrel",
                    "content": "Generate  (do not generate) pc-relative addressing.  The -mpcrel option requires that the\nmedium code model (-mcmodel=medium) and  prefixed  addressing  (-mprefixed)  options  are\nenabled.\n"
                },
                {
                    "name": "-mprefixed",
                    "content": ""
                },
                {
                    "name": "-mno-prefixed",
                    "content": "Generate  (do  not generate) addressing modes using prefixed load and store instructions.\nThe -mprefixed option requires that the option -mcpu=power10 (or later) is enabled.\n"
                },
                {
                    "name": "-mmma",
                    "content": ""
                },
                {
                    "name": "-mno-mma",
                    "content": "Generate (do not generate) the MMA instructions.   The  -mma  option  requires  that  the\noption -mcpu=power10 (or later) is enabled.\n"
                },
                {
                    "name": "-mrop-protect",
                    "content": ""
                },
                {
                    "name": "-mno-rop-protect",
                    "content": "Generate (do not generate) ROP protection instructions when the target processor supports\nthem.  Currently this option disables the shrink-wrap optimization (-fshrink-wrap).\n"
                },
                {
                    "name": "-mprivileged",
                    "content": ""
                },
                {
                    "name": "-mno-privileged",
                    "content": "Generate (do not generate) code that will run in privileged state.\n"
                },
                {
                    "name": "-mblock-ops-unaligned-vsx",
                    "content": ""
                },
                {
                    "name": "-mno-block-ops-unaligned-vsx",
                    "content": "Generate  (do  not  generate)  unaligned  vsx  loads  and  stores for inline expansion of\n\"memcpy\" and \"memmove\".\n"
                },
                {
                    "name": "--param rs6000-vect-unroll-limit=",
                    "content": "The vectorizer will check with target  information  to  determine  whether  it  would  be\nbeneficial  to  unroll the main vectorized loop and by how much.  This parameter sets the\nupper bound of how much the vectorizer will unroll the main loop.  The default  value  is\nfour.\n\nRX Options\n\nThese command-line options are defined for RX targets:\n",
                    "long": "--param"
                },
                {
                    "name": "-m64bit-doubles",
                    "content": ""
                },
                {
                    "name": "-m32bit-doubles",
                    "content": "Make  the \"double\" data type be 64 bits (-m64bit-doubles) or 32 bits (-m32bit-doubles) in\nsize.  The default is -m32bit-doubles.  Note RX floating-point  hardware  only  works  on\n32-bit values, which is why the default is -m32bit-doubles.\n"
                },
                {
                    "name": "-fpu",
                    "content": ""
                },
                {
                    "name": "-nofpu",
                    "content": "Enables  (-fpu)  or disables (-nofpu) the use of RX floating-point hardware.  The default\nis enabled for the RX600 series and disabled for the RX200 series.\n\nFloating-point instructions are only generated for 32-bit floating-point values, however,\nso the FPU hardware is not used for doubles if the -m64bit-doubles option is used.\n\nNote If the -fpu option is  enabled  then  -funsafe-math-optimizations  is  also  enabled\nautomatically.  This is because the RX FPU instructions are themselves unsafe.\n"
                },
                {
                    "name": "-mcpu=_",
                    "content": "Selects  the  type  of  RX  CPU to be targeted.  Currently three types are supported, the\ngeneric RX600 and RX200 series hardware and the  specific  RX610  CPU.   The  default  is\nRX600.\n\nThe  only  difference  between  RX600  and  RX610  is that the RX610 does not support the\n\"MVTIPL\" instruction.\n\nThe RX200 series does not have a hardware floating-point unit and so -nofpu is enabled by\ndefault when this type is selected.\n"
                },
                {
                    "name": "-mbig-endian-data",
                    "content": ""
                },
                {
                    "name": "-mlittle-endian-data",
                    "content": "Store data (but not code) in the big-endian format.  The default is -mlittle-endian-data,\ni.e. to store data in the little-endian format.\n"
                },
                {
                    "name": "-msmall-data-limit=_",
                    "content": "Specifies the maximum size in bytes of global and static variables which  can  be  placed\ninto the small data area.  Using the small data area can lead to smaller and faster code,\nbut  the  size  of area is limited and it is up to the programmer to ensure that the area\ndoes not overflow.  Also when the small data area is  used  one  of  the  RX's  registers\n(usually  \"r13\")  is reserved for use pointing to this area, so it is no longer available\nfor use by the compiler.  This could result in slower and/or larger code if variables are\npushed onto the stack instead of being held in this register.\n\nNote, common variables (variables that have not been initialized) and constants  are  not\nplaced  into  the  small  data  area as they are assigned to other sections in the output\nexecutable.\n\nThe default value is zero, which disables  this  feature.   Note,  this  feature  is  not\nenabled  by  default with higher optimization levels (-O2 etc) because of the potentially\ndetrimental effects of reserving a register.  It is up to the  programmer  to  experiment\nand discover whether this feature is of benefit to their program.  See the description of\nthe -mpid option for a description of how the actual register to hold the small data area\npointer is chosen.\n"
                },
                {
                    "name": "-msim",
                    "content": ""
                },
                {
                    "name": "-mno-sim",
                    "content": "Use the simulator runtime.  The default is to use the libgloss board-specific runtime.\n"
                },
                {
                    "name": "-mas100-syntax",
                    "content": ""
                },
                {
                    "name": "-mno-as100-syntax",
                    "content": "When  generating  assembler  output  use a syntax that is compatible with Renesas's AS100\nassembler.  This syntax can also be handled  by  the  GAS  assembler,  but  it  has  some\nrestrictions so it is not generated by default.\n"
                },
                {
                    "name": "-mmax-constant-size=_",
                    "content": "Specifies  the  maximum size, in bytes, of a constant that can be used as an operand in a\nRX instruction.  Although the RX instruction set does allow constants of up to 4 bytes in\nlength to be used in instructions, a longer value equates to a longer instruction.   Thus\nin  some  circumstances  it  can be beneficial to restrict the size of constants that are\nused in instructions.  Constants that are too big are instead placed into a constant pool\nand referenced via register indirection.\n\nThe value N can be between 0 and 4.  A value of 0 (the default) or 4 means that constants\nof any size are allowed.\n"
                },
                {
                    "name": "-mrelax",
                    "content": "Enable linker relaxation.  Linker relaxation is a process whereby the linker attempts  to\nreduce  the  size  of  a  program  by  finding  shorter versions of various instructions.\nDisabled by default.\n"
                },
                {
                    "name": "-mint-register=_",
                    "content": "Specify the number of registers to reserve for fast  interrupt  handler  functions.   The\nvalue  N  can be between 0 and 4.  A value of 1 means that register \"r13\" is reserved for\nthe exclusive use of fast interrupt handlers.  A value of 2 reserves \"r13\" and \"r12\".   A\nvalue  of  3  reserves  \"r13\",  \"r12\"  and \"r11\", and a value of 4 reserves \"r13\" through\n\"r10\".  A value of 0, the default, does not reserve any registers.\n"
                },
                {
                    "name": "-msave-acc-in-interrupts",
                    "content": "Specifies that interrupt handler functions  should  preserve  the  accumulator  register.\nThis  is  only  necessary  if normal code might use the accumulator register, for example\nbecause it performs 64-bit multiplications.  The default is to ignore the accumulator  as\nthis makes the interrupt handlers faster.\n"
                },
                {
                    "name": "-mpid",
                    "content": ""
                },
                {
                    "name": "-mno-pid",
                    "content": "Enables the generation of position independent data.  When enabled any access to constant\ndata  is  done  via  an  offset  from a base address held in a register.  This allows the\nlocation of constant data to be determined at run time without requiring  the  executable\nto  be  relocated,  which  is  a  benefit  to  embedded  applications  with  tight memory\nconstraints.  Data that can be modified is not affected by this option.\n\nNote, using this feature reserves a register, usually \"r13\", for the constant  data  base\naddress.   This  can  result  in  slower  and/or  larger  code, especially in complicated\nfunctions.\n\nThe actual register chosen to hold the constant data base address  depends  upon  whether\nthe  -msmall-data-limit  and/or  the  -mint-register  command-line  options  are enabled.\nStarting with register \"r13\" and proceeding downwards, registers are allocated  first  to\nsatisfy  the  requirements  of -mint-register, then -mpid and finally -msmall-data-limit.\nThus it is possible for the small data area register to be \"r8\" if both  -mint-register=4\nand -mpid are specified on the command line.\n\nBy  default  this  feature  is not enabled.  The default can be restored via the -mno-pid\ncommand-line option.\n"
                },
                {
                    "name": "-mno-warn-multiple-fast-interrupts",
                    "content": ""
                },
                {
                    "name": "-mwarn-multiple-fast-interrupts",
                    "content": "Prevents GCC from issuing a warning message if it finds  more  than  one  fast  interrupt\nhandler  when  it  is compiling a file.  The default is to issue a warning for each extra\nfast interrupt handler found, as the RX only supports one such interrupt.\n"
                },
                {
                    "name": "-mallow-string-insns",
                    "content": ""
                },
                {
                    "name": "-mno-allow-string-insns",
                    "content": "Enables or disables the use of the string  manipulation  instructions  \"SMOVF\",  \"SCMPU\",\n\"SMOVB\",  \"SMOVU\", \"SUNTIL\" \"SWHILE\" and also the \"RMPA\" instruction.  These instructions\nmay prefetch data, which is not safe to do if accessing an I/O  register.   (See  section\n12.2.7 of the RX62N Group User's Manual for more information).\n\nThe  default  is  to allow these instructions, but it is not possible for GCC to reliably\ndetect all circumstances where a string instruction  might  be  used  to  access  an  I/O\nregister,  so their use cannot be disabled automatically.  Instead it is reliant upon the\nprogrammer to use the -mno-allow-string-insns option if their program accesses I/O space.\n\nWhen  the  instructions   are   enabled   GCC   defines   the   C   preprocessor   symbol\n\"RXALLOWSTRINGINSNS\",       otherwise       it       defines       the      symbol\n\"RXDISALLOWSTRINGINSNS\".\n"
                },
                {
                    "name": "-mjsr",
                    "content": ""
                },
                {
                    "name": "-mno-jsr",
                    "content": "Use only (or not only) \"JSR\" instructions to access functions.  This option can  be  used\nwhen code size exceeds the range of \"BSR\" instructions.  Note that -mno-jsr does not mean\nto not use \"JSR\" but instead means that any type of branch may be used.\n\nNote: The generic GCC command-line option -ffixed-reg has special significance to the RX port\nwhen  used  with  the  \"interrupt\"  function  attribute.  This attribute indicates a function\nintended to process fast interrupts.  GCC ensures that it  only  uses  the  registers  \"r10\",\n\"r11\",  \"r12\"  and/or  \"r13\"  and  only  provided  that  the  normal use of the corresponding\nregisters have been restricted via the -ffixed-reg or -mint-register command-line options.\n\nS/390 and zSeries Options\n\nThese are the -m options defined for the S/390 and zSeries architecture.\n"
                },
                {
                    "name": "-mhard-float",
                    "content": ""
                },
                {
                    "name": "-msoft-float",
                    "content": "Use (do not use) the hardware floating-point instructions  and  registers  for  floating-\npoint  operations.   When  -msoft-float  is  specified, functions in libgcc.a are used to\nperform  floating-point  operations.   When  -mhard-float  is  specified,  the   compiler\ngenerates IEEE floating-point instructions.  This is the default.\n"
                },
                {
                    "name": "-mhard-dfp",
                    "content": ""
                },
                {
                    "name": "-mno-hard-dfp",
                    "content": "Use  (do  not use) the hardware decimal-floating-point instructions for decimal-floating-\npoint operations.  When -mno-hard-dfp is specified, functions in  libgcc.a  are  used  to\nperform  decimal-floating-point  operations.   When -mhard-dfp is specified, the compiler\ngenerates  decimal-floating-point  hardware  instructions.   This  is  the  default   for\n-march=z9-ec or higher.\n"
                },
                {
                    "name": "-mlong-double-64",
                    "content": ""
                },
                {
                    "name": "-mlong-double-128",
                    "content": "These  switches control the size of \"long double\" type. A size of 64 bits makes the \"long\ndouble\" type equivalent to the \"double\" type. This is the default.\n"
                },
                {
                    "name": "-mbackchain",
                    "content": ""
                },
                {
                    "name": "-mno-backchain",
                    "content": "Store (do not store) the address of the caller's frame  as  backchain  pointer  into  the\ncallee's  stack  frame.  A backchain may be needed to allow debugging using tools that do\nnot understand DWARF call frame information.  When -mno-packed-stack is  in  effect,  the\nbackchain  pointer  is stored at the bottom of the stack frame; when -mpacked-stack is in\neffect, the backchain is placed into the topmost word of the 96/160  byte  register  save\narea.\n\nIn  general,  code  compiled  with -mbackchain is call-compatible with code compiled with\n-mno-backchain; however, use of the backchain for  debugging  purposes  usually  requires\nthat  the  whole  binary  is  built  with  -mbackchain.   Note  that  the  combination of\n-mbackchain, -mpacked-stack and -mhard-float is not supported.  In order to build a linux\nkernel use -msoft-float.\n\nThe default is to not maintain the backchain.\n"
                },
                {
                    "name": "-mpacked-stack",
                    "content": ""
                },
                {
                    "name": "-mno-packed-stack",
                    "content": "Use (do not use) the packed stack  layout.   When  -mno-packed-stack  is  specified,  the\ncompiler uses the all fields of the 96/160 byte register save area only for their default\npurpose;  unused  fields  still  take  up stack space.  When -mpacked-stack is specified,\nregister save slots are densely packed at the top of the register save area; unused space\nis reused for other purposes, allowing for more efficient  use  of  the  available  stack\nspace.  However, when -mbackchain is also in effect, the topmost word of the save area is\nalways  used  to store the backchain, and the return address register is always saved two\nwords below the backchain.\n\nAs long as the stack frame backchain is not used, code generated with  -mpacked-stack  is\ncall-compatible  with  code  generated  with  -mno-packed-stack.   Note that some non-FSF\nreleases of GCC 2.95 for S/390 or zSeries  generated  code  that  uses  the  stack  frame\nbackchain at run time, not just for debugging purposes.  Such code is not call-compatible\nwith  code compiled with -mpacked-stack.  Also, note that the combination of -mbackchain,\n-mpacked-stack and -mhard-float is not supported.  In order to build a linux  kernel  use\n-msoft-float.\n\nThe default is to not use the packed stack layout.\n"
                },
                {
                    "name": "-msmall-exec",
                    "content": ""
                },
                {
                    "name": "-mno-small-exec",
                    "content": "Generate  (or  do not generate) code using the \"bras\" instruction to do subroutine calls.\nThis only works reliably if the total executable size does not exceed 64k.   The  default\nis to use the \"basr\" instruction instead, which does not have this limitation.\n"
                },
                {
                    "name": "-m64",
                    "content": ""
                },
                {
                    "name": "-m31",
                    "content": "When  -m31  is  specified,  generate code compliant to the GNU/Linux for S/390 ABI.  When\n-m64 is specified, generate code compliant to the GNU/Linux for zSeries ABI.  This allows\nGCC in particular to generate 64-bit instructions.  For the s390 targets, the default  is\n-m31, while the s390x targets default to -m64.\n"
                },
                {
                    "name": "-mzarch",
                    "content": ""
                },
                {
                    "name": "-mesa",
                    "content": "When   -mzarch   is   specified,  generate  code  using  the  instructions  available  on\nz/Architecture.  When -mesa is specified, generate code using the instructions  available\non  ESA/390.   Note that -mesa is not possible with -m64.  When generating code compliant\nto the GNU/Linux for S/390 ABI, the default is -mesa.  When generating code compliant  to\nthe GNU/Linux for zSeries ABI, the default is -mzarch.\n"
                },
                {
                    "name": "-mhtm",
                    "content": ""
                },
                {
                    "name": "-mno-htm",
                    "content": "The  -mhtm option enables a set of builtins making use of instructions available with the\ntransactional execution  facility  introduced  with  the  IBM  zEnterprise  EC12  machine\ngeneration  S/390  System  z  Built-in Functions.  -mhtm is enabled by default when using\n-march=zEC12.\n"
                },
                {
                    "name": "-mvx",
                    "content": ""
                },
                {
                    "name": "-mno-vx",
                    "content": "When -mvx is specified, generate code using the instructions available  with  the  vector\nextension  facility  introduced with the IBM z13 machine generation.  This option changes\nthe ABI for some vector type values with regard to alignment and calling conventions.  In\ncase vector type values are being used in an ABI-relevant context  a  GAS  .gnuattribute\ncommand will be added to mark the resulting binary with the ABI used.  -mvx is enabled by\ndefault when using -march=z13.\n"
                },
                {
                    "name": "-mzvector",
                    "content": ""
                },
                {
                    "name": "-mno-zvector",
                    "content": "The  -mzvector  option enables vector language extensions and builtins using instructions\navailable with the  vector  extension  facility  introduced  with  the  IBM  z13  machine\ngeneration.  This option adds support for vector to be used as a keyword to define vector\ntype  variables and arguments.  vector is only available when GNU extensions are enabled.\nIt will not be expanded when requesting strict standard compliance  e.g.  with  -std=c99.\nIn  addition  to the GCC low-level builtins -mzvector enables a set of builtins added for\ncompatibility with AltiVec-style implementations like Power and Cell.  In order  to  make\nuse  of  these  builtins  the header file vecintrin.h needs to be included.  -mzvector is\ndisabled by default.\n"
                },
                {
                    "name": "-mmvcle",
                    "content": ""
                },
                {
                    "name": "-mno-mvcle",
                    "content": "Generate (or do not generate) code using the \"mvcle\" instruction to perform block  moves.\nWhen  -mno-mvcle  is  specified,  use  a  \"mvc\" loop instead.  This is the default unless\noptimizing for size.\n"
                },
                {
                    "name": "-mdebug",
                    "content": ""
                },
                {
                    "name": "-mno-debug",
                    "content": "Print (or do not print) additional debug information when compiling.  The default  is  to\nnot print debug information.\n"
                },
                {
                    "name": "-march=_",
                    "content": "Generate code that runs on cpu-type, which is the name of a system representing a certain\nprocessor  type.   Possible  values  for  cpu-type  are  z900/arch5,  z990/arch6, z9-109,\nz9-ec/arch7,  z10/arch8,   z196/arch9,   zEC12,   z13/arch11,   z14/arch12,   z15/arch13,\nz16/arch14, and native.\n\nThe default is -march=z900.\n\nSpecifying  native as cpu type can be used to select the best architecture option for the\nhost processor.  -march=native has no effect if GCC does not recognize the processor.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "Tune to cpu-type everything applicable about the generated code, except for the  ABI  and\nthe  set  of  available  instructions.   The  list  of cpu-type values is the same as for\n-march.  The default is the value used for -march.\n"
                },
                {
                    "name": "-mtpf-trace",
                    "content": ""
                },
                {
                    "name": "-mno-tpf-trace",
                    "content": "Generate code that adds (does not add) in TPF OS specific branches to trace  routines  in\nthe operating system.  This option is off by default, even when compiling for the TPF OS.\n"
                },
                {
                    "name": "-mtpf-trace-skip",
                    "content": ""
                },
                {
                    "name": "-mno-tpf-trace-skip",
                    "content": "Generate  code  that  changes  (does  not  change)  the default branch targets enabled by\n-mtpf-trace to point to specialized trace routines providing the ability  of  selectively\nskipping function trace entries for the TPF OS.  This option is off by default, even when\ncompiling for the TPF OS and specifying -mtpf-trace.\n"
                },
                {
                    "name": "-mfused-madd",
                    "content": ""
                },
                {
                    "name": "-mno-fused-madd",
                    "content": "Generate  code  that  uses  (does  not  use)  the  floating-point multiply and accumulate\ninstructions.  These instructions are generated by default if hardware floating point  is\nused.\n"
                },
                {
                    "name": "-mwarn-framesize=_",
                    "content": "Emit  a  warning if the current function exceeds the given frame size.  Because this is a\ncompile-time check it doesn't need to be a real problem when the  program  runs.   It  is\nintended  to  identify functions that most probably cause a stack overflow.  It is useful\nto be used in an environment with limited stack size e.g. the linux kernel.\n"
                },
                {
                    "name": "-mwarn-dynamicstack",
                    "content": "Emit a warning if the function calls \"alloca\" or uses dynamically-sized arrays.  This  is\ngenerally a bad idea with a limited stack size.\n"
                },
                {
                    "name": "-mstack-guard=_",
                    "content": ""
                },
                {
                    "name": "-mstack-size=_",
                    "content": "If  these  options  are  provided the S/390 back end emits additional instructions in the\nfunction prologue that trigger a trap if the stack size is stack-guard  bytes  above  the\nstack-size  (remember that the stack on S/390 grows downward).  If the stack-guard option\nis omitted the smallest power of 2 larger than the frame size of the compiled function is\nchosen.  These options are intended to be used to help debugging stack overflow problems.\nThe additionally emitted code causes only little overhead and hence can also be  used  in\nproduction-like  systems  without greater performance degradation.  The given values have\nto be exact powers of 2 and  stack-size  has  to  be  greater  than  stack-guard  without\nexceeding  64k.   In  order  to be efficient the extra code makes the assumption that the\nstack starts at an address aligned to the value given  by  stack-size.   The  stack-guard\noption can only be used in conjunction with stack-size.\n"
                },
                {
                    "name": "-mhotpatch=_",
                    "content": "If  the  hotpatch  option is enabled, a \"hot-patching\" function prologue is generated for\nall functions in the compilation unit.  The funtion label is  prepended  with  the  given\nnumber of two-byte NOP instructions (pre-halfwords, maximum 1000000).  After the label, 2\n*  post-halfwords  bytes  are  appended,  using  the  largest  NOP  like instructions the\narchitecture allows (maximum 1000000).\n\nIf both arguments are zero, hotpatching is disabled.\n\nThis option can be overridden for individual functions with the \"hotpatch\" attribute.\n\nSH Options\n\nThese -m options are defined for the SH implementations:\n"
                },
                {
                    "name": "-m1",
                    "content": ""
                },
                {
                    "name": "-m2",
                    "content": ""
                },
                {
                    "name": "-m2e",
                    "content": "Generate code for the SH2e.\n"
                },
                {
                    "name": "-m2a-nofpu",
                    "content": "Generate code for the SH2a without FPU, or  for  a  SH2a-FPU  in  such  a  way  that  the\nfloating-point unit is not used.\n"
                },
                {
                    "name": "-m2a-single-only",
                    "content": "Generate  code  for  the  SH2a-FPU, in such a way that no double-precision floating-point\noperations are used.\n"
                },
                {
                    "name": "-m2a-single",
                    "content": "Generate code for the SH2a-FPU assuming the floating-point unit  is  in  single-precision\nmode by default.\n"
                },
                {
                    "name": "-m2a",
                    "content": "Generate  code  for  the SH2a-FPU assuming the floating-point unit is in double-precision\nmode by default.\n"
                },
                {
                    "name": "-m3",
                    "content": ""
                },
                {
                    "name": "-m3e",
                    "content": "Generate code for the SH3e.\n"
                },
                {
                    "name": "-m4-nofpu",
                    "content": "Generate code for the SH4 without a floating-point unit.\n"
                },
                {
                    "name": "-m4-single-only",
                    "content": "Generate code for the SH4 with a floating-point unit that only supports  single-precision\narithmetic.\n"
                },
                {
                    "name": "-m4-single",
                    "content": "Generate code for the SH4 assuming the floating-point unit is in single-precision mode by\ndefault.\n"
                },
                {
                    "name": "-m4",
                    "content": ""
                },
                {
                    "name": "-m4-100",
                    "content": "Generate code for SH4-100.\n"
                },
                {
                    "name": "-m4-100-nofpu",
                    "content": "Generate code for SH4-100 in such a way that the floating-point unit is not used.\n"
                },
                {
                    "name": "-m4-100-single",
                    "content": "Generate code for SH4-100 assuming the floating-point unit is in single-precision mode by\ndefault.\n"
                },
                {
                    "name": "-m4-100-single-only",
                    "content": "Generate  code  for  SH4-100  in  such  a  way  that  no  double-precision floating-point\noperations are used.\n"
                },
                {
                    "name": "-m4-200",
                    "content": "Generate code for SH4-200.\n"
                },
                {
                    "name": "-m4-200-nofpu",
                    "content": "Generate code for SH4-200 without in such a way that the floating-point unit is not used.\n"
                },
                {
                    "name": "-m4-200-single",
                    "content": "Generate code for SH4-200 assuming the floating-point unit is in single-precision mode by\ndefault.\n"
                },
                {
                    "name": "-m4-200-single-only",
                    "content": "Generate code  for  SH4-200  in  such  a  way  that  no  double-precision  floating-point\noperations are used.\n"
                },
                {
                    "name": "-m4-300",
                    "content": "Generate code for SH4-300.\n"
                },
                {
                    "name": "-m4-300-nofpu",
                    "content": "Generate code for SH4-300 without in such a way that the floating-point unit is not used.\n"
                },
                {
                    "name": "-m4-300-single",
                    "content": "Generate  code  for  SH4-300  in  such  a  way  that  no  double-precision floating-point\noperations are used.\n"
                },
                {
                    "name": "-m4-300-single-only",
                    "content": "Generate code  for  SH4-300  in  such  a  way  that  no  double-precision  floating-point\noperations are used.\n"
                },
                {
                    "name": "-m4-340",
                    "content": "Generate code for SH4-340 (no MMU, no FPU).\n"
                },
                {
                    "name": "-m4-500",
                    "content": "Generate code for SH4-500 (no FPU).  Passes -isa=sh4-nofpu to the assembler.\n"
                },
                {
                    "name": "-m4a-nofpu",
                    "content": "Generate code for the SH4al-dsp, or for a SH4a in such a way that the floating-point unit\nis not used.\n"
                },
                {
                    "name": "-m4a-single-only",
                    "content": "Generate  code  for  the  SH4a,  in  such  a  way that no double-precision floating-point\noperations are used.\n"
                },
                {
                    "name": "-m4a-single",
                    "content": "Generate code for the SH4a assuming the floating-point unit is in  single-precision  mode\nby default.\n"
                },
                {
                    "name": "-m4a",
                    "content": "Generate code for the SH4a.\n"
                },
                {
                    "name": "-m4al",
                    "content": "Same  as -m4a-nofpu, except that it implicitly passes -dsp to the assembler.  GCC doesn't\ngenerate any DSP instructions at the moment.\n"
                },
                {
                    "name": "-mb",
                    "content": ""
                },
                {
                    "name": "-ml",
                    "content": ""
                },
                {
                    "name": "-mdalign",
                    "content": "Align doubles at 64-bit boundaries.  Note that this changes the calling conventions,  and\nthus some functions from the standard C library do not work unless you recompile it first\nwith -mdalign.\n"
                },
                {
                    "name": "-mrelax",
                    "content": "Shorten  some  address  references  at  link  time, when possible; uses the linker option\n-relax.\n"
                },
                {
                    "name": "-mbigtable",
                    "content": "Use 32-bit offsets in \"switch\" tables.  The default is to use 16-bit offsets.\n"
                },
                {
                    "name": "-mbitops",
                    "content": "Enable the use of bit manipulation instructions on SH2A.\n"
                },
                {
                    "name": "-mfmovd",
                    "content": "Enable the use of the instruction \"fmovd\".  Check -mdalign for alignment constraints.\n"
                },
                {
                    "name": "-mrenesas",
                    "content": "Comply with the calling conventions defined by Renesas.\n"
                },
                {
                    "name": "-mno-renesas",
                    "content": "Comply with the calling conventions defined for GCC before the Renesas  conventions  were\navailable.  This option is the default for all targets of the SH toolchain.\n"
                },
                {
                    "name": "-mnomacsave",
                    "content": "Mark the \"MAC\" register as call-clobbered, even if -mrenesas is given.\n"
                },
                {
                    "name": "-mieee",
                    "content": ""
                },
                {
                    "name": "-mno-ieee",
                    "content": "Control  the IEEE compliance of floating-point comparisons, which affects the handling of\ncases where the result of a comparison is unordered.  By  default  -mieee  is  implicitly\nenabled.   If -ffinite-math-only is enabled -mno-ieee is implicitly set, which results in\nfaster floating-point greater-equal and less-equal comparisons.   The  implicit  settings\ncan be overridden by specifying either -mieee or -mno-ieee.\n"
                },
                {
                    "name": "-minline-ic_invalidate",
                    "content": "Inline  code  to  invalidate  instruction  cache entries after setting up nested function\ntrampolines.  This option has no effect if -musermode is in effect and the selected  code\ngeneration  option  (e.g.  -m4) does not allow the use of the \"icbi\" instruction.  If the\nselected code generation option does not allow the use of  the  \"icbi\"  instruction,  and\n-musermode  is  not in effect, the inlined code manipulates the instruction cache address\narray directly with an associative write.  This not only requires privileged mode at  run\ntime,  but  it  also  fails  if the cache line had been mapped via the TLB and has become\nunmapped.\n"
                },
                {
                    "name": "-misize",
                    "content": "Dump instruction size and location in the assembly code.\n"
                },
                {
                    "name": "-mpadstruct",
                    "content": "This option is deprecated.   It  pads  structures  to  multiple  of  4  bytes,  which  is\nincompatible with the SH ABI.\n"
                },
                {
                    "name": "-matomic-model=_",
                    "content": "Sets  the model of atomic operations and additional parameters as a comma separated list.\nFor details on the atomic built-in functions see atomic Builtins.  The following models\nand parameters are supported:\n\nnone\nDisable compiler generated  atomic  sequences  and  emit  library  calls  for  atomic\noperations.  This is the default if the target is not \"sh*-*-linux*\".\n\nsoft-gusa\nGenerate  GNU/Linux compatible gUSA software atomic sequences for the atomic built-in\nfunctions.  The generated  atomic  sequences  require  additional  support  from  the\ninterrupt/exception  handling  code  of the system and are only suitable for SH3* and\nSH4* single-core systems.  This option is enabled  by  default  when  the  target  is\n\"sh*-*-linux*\" and SH3* or SH4*.  When the target is SH4A, this option also partially\nutilizes  the  hardware  atomic  instructions  \"movli.l\" and \"movco.l\" to create more\nefficient code, unless strict is specified.\n\nsoft-tcb\nGenerate software atomic sequences that use a variable in the thread  control  block.\nThis  is  a  variation  of the gUSA sequences which can also be used on SH1* and SH2*\ntargets.   The  generated  atomic  sequences  require  additional  support  from  the\ninterrupt/exception handling code of the system and are only suitable for single-core\nsystems.   When  using  this  model, the gbr-offset= parameter has to be specified as\nwell.\n\nsoft-imask\nGenerate software atomic sequences that temporarily  disable  interrupts  by  setting\n\"SR.IMASK  =  1111\".   This model works only when the program runs in privileged mode\nand  is  only  suitable  for  single-core  systems.   Additional  support  from   the\ninterrupt/exception  handling  code  of  the  system  is not required.  This model is\nenabled by default when the target is \"sh*-*-linux*\" and SH1* or SH2*.\n\nhard-llcs\nGenerate hardware atomic sequences using the  \"movli.l\"  and  \"movco.l\"  instructions\nonly.   This is only available on SH4A and is suitable for multi-core systems.  Since\nthe hardware instructions support only 32 bit atomic variables access to 8 or 16  bit\nvariables  is  emulated with 32 bit accesses.  Code compiled with this option is also\ncompatible with other software atomic model interrupt/exception handling  systems  if\nexecuted on an SH4A system.  Additional support from the interrupt/exception handling\ncode of the system is not required for this model.\n\ngbr-offset=\nThis  parameter  specifies  the offset in bytes of the variable in the thread control\nblock structure that should be used by the generated atomic sequences when the  soft-\ntcb  model  has  been  selected.   For  other  models this parameter is ignored.  The\nspecified value must be an integer multiple of four and in the range 0-1020.\n\nstrict\nThis parameter prevents mixed usage of multiple  atomic  models,  even  if  they  are\ncompatible,  and  makes the compiler generate atomic sequences of the specified model\nonly.\n"
                },
                {
                    "name": "-mtas",
                    "content": "Generate the \"tas.b\" opcode for \"atomictestandset\".  Notice that  depending  on  the\nparticular  hardware  and software configuration this can degrade overall performance due\nto the operand cache line flushes that are implied by the \"tas.b\" instruction.  On multi-\ncore SH4A processors the \"tas.b\" instruction must be  used  with  caution  since  it  can\nresult in data corruption for certain cache configurations.\n"
                },
                {
                    "name": "-mprefergot",
                    "content": "When  generating  position-independent  code, emit function calls using the Global Offset\nTable instead of the Procedure Linkage Table.\n"
                },
                {
                    "name": "-musermode",
                    "content": ""
                },
                {
                    "name": "-mno-usermode",
                    "content": "Don't allow (allow) the compiler generating privileged mode code.  Specifying  -musermode\nalso  implies  -mno-inline-icinvalidate if the inlined code would not work in user mode.\n-musermode is the default when the target is \"sh*-*-linux*\".  If the target  is  SH1*  or\nSH2* -musermode has no effect, since there is no user mode.\n"
                },
                {
                    "name": "-multcost=_",
                    "content": "Set the cost to assume for a multiply insn.\n"
                },
                {
                    "name": "-mdiv=_",
                    "content": "Set  the  division  strategy to be used for integer division operations.  strategy can be\none of:\n\ncall-div1\nCalls a library function that uses the single-step  division  instruction  \"div1\"  to\nperform  the  operation.   Division by zero calculates an unspecified result and does\nnot trap.  This is the default except for SH4, SH2A and SHcompact.\n\ncall-fp\nCalls a library function that performs the operation  in  double  precision  floating\npoint.   Division by zero causes a floating-point exception.  This is the default for\nSHcompact with FPU.  Specifying this for targets that do not have a double  precision\nFPU defaults to \"call-div1\".\n\ncall-table\nCalls  a  library function that uses a lookup table for small divisors and the \"div1\"\ninstruction with case distinction for larger divisors.  Division by  zero  calculates\nan  unspecified  result  and does not trap.  This is the default for SH4.  Specifying\nthis for targets that do not have dynamic shift instructions defaults to \"call-div1\".\n\nWhen a division strategy has not been specified the default strategy is selected based on\nthe current target.  For SH2A the default strategy  is  to  use  the  \"divs\"  and  \"divu\"\ninstructions instead of library function calls.\n"
                },
                {
                    "name": "-maccumulate-outgoing-args",
                    "content": "Reserve  space  once  for  outgoing arguments in the function prologue rather than around\neach call.  Generally beneficial for performance and size.  Also needed for unwinding  to\navoid changing the stack frame around conditional code.\n"
                },
                {
                    "name": "-mdivsi3_libfunc=_",
                    "content": "Set  the name of the library function used for 32-bit signed division to name.  This only\naffects the name used in the call division strategies, and the compiler still expects the\nsame sets of input/output/clobbered registers as if this option were not present.\n"
                },
                {
                    "name": "-mfixed-range=_",
                    "content": "Generate code treating the given register range as fixed registers.  A fixed register  is\none  that  the register allocator cannot use.  This is useful when compiling kernel code.\nA register range is specified as two registers separated by a  dash.   Multiple  register\nranges can be specified separated by a comma.\n"
                },
                {
                    "name": "-mbranch-cost=_",
                    "content": "Assume num to be the cost for a branch instruction.  Higher numbers make the compiler try\nto  generate  more  branch-free code if possible.  If not specified the value is selected\ndepending on the processor type that is being compiled for.\n"
                },
                {
                    "name": "-mzdcbranch",
                    "content": ""
                },
                {
                    "name": "-mno-zdcbranch",
                    "content": "Assume (do not assume) that zero displacement conditional branch  instructions  \"bt\"  and\n\"bf\"  are  fast.   If  -mzdcbranch  is  specified, the compiler prefers zero displacement\nbranch code sequences.  This is enabled by default when generating code for SH4 and SH4A.\nIt can be explicitly disabled by specifying -mno-zdcbranch.\n"
                },
                {
                    "name": "-mcbranch-force-delay-slot",
                    "content": "Force the usage of delay slots for conditional branches, which stuffs the delay slot with\na \"nop\" if a suitable instruction cannot be found.  By default this option  is  disabled.\nIt can be enabled to work around hardware bugs as found in the original SH7055.\n"
                },
                {
                    "name": "-mfused-madd",
                    "content": ""
                },
                {
                    "name": "-mno-fused-madd",
                    "content": "Generate  code  that  uses  (does  not  use)  the  floating-point multiply and accumulate\ninstructions.  These instructions are generated by default if hardware floating point  is\nused.  The machine-dependent -mfused-madd option is now mapped to the machine-independent\n-ffp-contract=fast option, and -mno-fused-madd is mapped to -ffp-contract=off.\n"
                },
                {
                    "name": "-mfsca",
                    "content": ""
                },
                {
                    "name": "-mno-fsca",
                    "content": "Allow  or  disallow  the  compiler  to  emit  the  \"fsca\" instruction for sine and cosine\napproximations.    The   option   -mfsca   must   be    used    in    combination    with\n-funsafe-math-optimizations.   It  is  enabled  by default when generating code for SH4A.\nUsing    -mno-fsca    disables    sine    and    cosine    approximations     even     if\n-funsafe-math-optimizations is in effect.\n"
                },
                {
                    "name": "-mfsrra",
                    "content": ""
                },
                {
                    "name": "-mno-fsrra",
                    "content": "Allow or disallow the compiler to emit the \"fsrra\" instruction for reciprocal square root\napproximations.     The    option    -mfsrra   must   be   used   in   combination   with\n-funsafe-math-optimizations and  -ffinite-math-only.   It  is  enabled  by  default  when\ngenerating   code   for   SH4A.    Using   -mno-fsrra  disables  reciprocal  square  root\napproximations even if -funsafe-math-optimizations and -ffinite-math-only are in effect.\n"
                },
                {
                    "name": "-mpretend-cmove",
                    "content": "Prefer zero-displacement conditional branches for conditional move instruction  patterns.\nThis can result in faster code on the SH4 processor.\n"
                },
                {
                    "name": "-mfdpic",
                    "content": "Generate code using the FDPIC ABI.\n\nSolaris 2 Options\n\nThese -m options are supported on Solaris 2:\n"
                },
                {
                    "name": "-mclear-hwcap",
                    "content": "-mclear-hwcap  tells  the  compiler  to remove the hardware capabilities generated by the\nSolaris assembler.  This is only necessary when  object  files  use  ISA  extensions  not\nsupported by the current machine, but check at runtime whether or not to use them.\n"
                },
                {
                    "name": "-mimpure-text",
                    "content": "-mimpure-text, used in addition to -shared, tells the compiler to not pass -z text to the\nlinker  when linking a shared object.  Using this option, you can link position-dependent\ncode into a shared object.\n\n-mimpure-text suppresses the \"relocations remain  against  allocatable  but  non-writable\nsections\"  linker  error  message.   However,  the necessary relocations trigger copy-on-\nwrite, and the shared object is not actually shared across processes.  Instead  of  using\n-mimpure-text, you should compile all source code with -fpic or -fPIC.\n\nThese switches are supported in addition to the above on Solaris 2:\n"
                },
                {
                    "name": "-pthreads",
                    "content": "This is a synonym for -pthread.\n\nSPARC Options\n\nThese -m options are supported on the SPARC:\n"
                },
                {
                    "name": "-mno-app-regs",
                    "content": ""
                },
                {
                    "name": "-mapp-regs",
                    "content": "Specify  -mapp-regs  to generate output using the global registers 2 through 4, which the\nSPARC SVR4 ABI reserves for applications.   Like  the  global  register  1,  each  global\nregister  2  through  4  is  then  treated  as an allocable register that is clobbered by\nfunction calls.  This is the default.\n\nTo  be  fully  SVR4  ABI-compliant  at  the  cost  of  some  performance  loss,   specify\n-mno-app-regs.  You should compile libraries and system software with this option.\n"
                },
                {
                    "name": "-mflat",
                    "content": ""
                },
                {
                    "name": "-mno-flat",
                    "content": "With  -mflat,  the compiler does not generate save/restore instructions and uses a \"flat\"\nor single register window model.  This model is  compatible  with  the  regular  register\nwindow  model.   The  local registers and the input registers (0--5) are still treated as\n\"call-saved\" registers and are saved on the stack as needed.\n\nWith -mno-flat (the default), the compiler generates  save/restore  instructions  (except\nfor leaf functions).  This is the normal operating mode.\n"
                },
                {
                    "name": "-mfpu",
                    "content": ""
                },
                {
                    "name": "-mhard-float",
                    "content": "Generate output containing floating-point instructions.  This is the default.\n"
                },
                {
                    "name": "-mno-fpu",
                    "content": ""
                },
                {
                    "name": "-msoft-float",
                    "content": "Generate  output  containing  library  calls  for floating point.  Warning: the requisite\nlibraries are not available for all  SPARC  targets.   Normally  the  facilities  of  the\nmachine's  usual  C  compiler  are  used,  but  this  cannot  be  done directly in cross-\ncompilation.  You must make your own arrangements to provide suitable  library  functions\nfor  cross-compilation.   The  embedded targets sparc-*-aout and sparclite-*-* do provide\nsoftware floating-point support.\n\n-msoft-float changes the calling convention in the output file;  therefore,  it  is  only\nuseful  if  you  compile  all  of a program with this option.  In particular, you need to\ncompile libgcc.a, the library that comes with GCC, with -msoft-float in order for this to\nwork.\n"
                },
                {
                    "name": "-mhard-quad-float",
                    "content": "Generate output containing quad-word (long double) floating-point instructions.\n"
                },
                {
                    "name": "-msoft-quad-float",
                    "content": "Generate output containing library  calls  for  quad-word  (long  double)  floating-point\ninstructions.   The  functions  called are those specified in the SPARC ABI.  This is the\ndefault.\n\nAs of this writing, there are no SPARC implementations that have hardware support for the\nquad-word floating-point instructions.  They all invoke a trap handler for one  of  these\ninstructions,  and then the trap handler emulates the effect of the instruction.  Because\nof the trap handler overhead, this is much slower than calling the ABI library  routines.\nThus the -msoft-quad-float option is the default.\n"
                },
                {
                    "name": "-mno-unaligned-doubles",
                    "content": ""
                },
                {
                    "name": "-munaligned-doubles",
                    "content": "Assume that doubles have 8-byte alignment.  This is the default.\n\nWith -munaligned-doubles, GCC assumes that doubles have 8-byte alignment only if they are\ncontained  in  another  type, or if they have an absolute address.  Otherwise, it assumes\nthey have 4-byte alignment.   Specifying  this  option  avoids  some  rare  compatibility\nproblems  with  code  generated  by  other  compilers.   It is not the default because it\nresults in a performance loss, especially for floating-point code.\n"
                },
                {
                    "name": "-muser-mode",
                    "content": ""
                },
                {
                    "name": "-mno-user-mode",
                    "content": "Do not generate code that can only run in supervisor mode.  This is relevant only for the\n\"casa\" instruction emitted for the LEON3 processor.  This is the default.\n"
                },
                {
                    "name": "-mfaster-structs",
                    "content": ""
                },
                {
                    "name": "-mno-faster-structs",
                    "content": "With -mfaster-structs, the compiler assumes that structures should have 8-byte alignment.\nThis enables the use of pairs of \"ldd\" and \"std\" instructions  for  copies  in  structure\nassignment,  in  place  of  twice  as many \"ld\" and \"st\" pairs.  However, the use of this\nchanged alignment directly violates the SPARC ABI.  Thus, it's intended only for  use  on\ntargets  where  the  developer  acknowledges that their resulting code is not directly in\nline with the rules of the ABI.\n"
                },
                {
                    "name": "-mstd-struct-return",
                    "content": ""
                },
                {
                    "name": "-mno-std-struct-return",
                    "content": "With -mstd-struct-return, the compiler generates checking  code  in  functions  returning\nstructures  or  unions to detect size mismatches between the two sides of function calls,\nas per the 32-bit ABI.\n\nThe default is -mno-std-struct-return.  This option has no effect in 64-bit mode.\n"
                },
                {
                    "name": "-mlra",
                    "content": ""
                },
                {
                    "name": "-mno-lra",
                    "content": "Enable Local Register Allocation.  This is the default for SPARC since GCC 7 so  -mno-lra\nneeds to be passed to get old Reload.\n"
                },
                {
                    "name": "-mcpu=_",
                    "content": "Set  the instruction set, register set, and instruction scheduling parameters for machine\ntype  cputype.   Supported  values  for  cputype  are  v7,  cypress,  v8,   supersparc,\nhypersparc,  leon,  leon3, leon3v7, leon5, sparclite, f930, f934, sparclite86x, sparclet,\ntsc701, v9, ultrasparc, ultrasparc3, niagara, niagara2, niagara3, niagara4, niagara7  and\nm8.\n\nNative  Solaris and GNU/Linux toolchains also support the value native, which selects the\nbest architecture option for the host processor.  -mcpu=native has no effect if GCC  does\nnot recognize the processor.\n\nDefault instruction scheduling parameters are used for values that select an architecture\nand not an implementation.  These are v7, v8, sparclite, sparclet, v9.\n\nHere is a list of each supported architecture and their supported implementations.\n\nv7  cypress, leon3v7\n\nv8  supersparc, hypersparc, leon, leon3, leon5\n\nsparclite\nf930, f934, sparclite86x\n\nsparclet\ntsc701\n\nv9  ultrasparc, ultrasparc3, niagara, niagara2, niagara3, niagara4, niagara7, m8\n\nBy  default  (unless  configured otherwise), GCC generates code for the V7 variant of the\nSPARC architecture.  With -mcpu=cypress, the compiler additionally optimizes it  for  the\nCypress  CY7C602  chip, as used in the SPARCStation/SPARCServer 3xx series.  This is also\nappropriate for the older SPARCStation 1, 2, IPX etc.\n\nWith -mcpu=v8, GCC generates code for the V8 variant of the SPARC architecture.  The only\ndifference from V7 code is that the compiler  emits  the  integer  multiply  and  integer\ndivide  instructions which exist in SPARC-V8 but not in SPARC-V7.  With -mcpu=supersparc,\nthe compiler  additionally  optimizes  it  for  the  SuperSPARC  chip,  as  used  in  the\nSPARCStation 10, 1000 and 2000 series.\n\nWith  -mcpu=sparclite,  GCC  generates  code  for  the  SPARClite  variant  of  the SPARC\narchitecture.  This adds the integer multiply,  integer  divide  step  and  scan  (\"ffs\")\ninstructions which exist in SPARClite but not in SPARC-V7.  With -mcpu=f930, the compiler\nadditionally  optimizes it for the Fujitsu MB86930 chip, which is the original SPARClite,\nwith no FPU.  With -mcpu=f934, the compiler additionally optimizes  it  for  the  Fujitsu\nMB86934 chip, which is the more recent SPARClite with FPU.\n\nWith   -mcpu=sparclet,  GCC  generates  code  for  the  SPARClet  variant  of  the  SPARC\narchitecture.  This adds the integer multiply, multiply/accumulate, integer  divide  step\nand  scan  (\"ffs\")  instructions  which  exist  in  SPARClet  but  not in SPARC-V7.  With\n-mcpu=tsc701, the compiler additionally optimizes it for the TEMIC SPARClet chip.\n\nWith -mcpu=v9, GCC generates code for the V9 variant of  the  SPARC  architecture.   This\nadds  64-bit  integer  and  floating-point move instructions, 3 additional floating-point\ncondition code registers and conditional move instructions.  With  -mcpu=ultrasparc,  the\ncompiler  additionally  optimizes  it  for  the  Sun  UltraSPARC  I/II/IIi  chips.   With\n-mcpu=ultrasparc3,  the  compiler  additionally  optimizes  it  for  the  Sun  UltraSPARC\nIII/III+/IIIi/IIIi+/IV/IV+   chips.    With   -mcpu=niagara,  the  compiler  additionally\noptimizes it for Sun UltraSPARC T1 chips.  With -mcpu=niagara2, the compiler additionally\noptimizes it for Sun UltraSPARC T2 chips. With -mcpu=niagara3, the compiler  additionally\noptimizes it for Sun UltraSPARC T3 chips.  With -mcpu=niagara4, the compiler additionally\noptimizes it for Sun UltraSPARC T4 chips.  With -mcpu=niagara7, the compiler additionally\noptimizes  it  for  Oracle  SPARC  M7  chips.   With  -mcpu=m8, the compiler additionally\noptimizes it for Oracle M8 chips.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "Set the instruction scheduling parameters for machine type cputype, but do not  set  the\ninstruction set or register set that the option -mcpu=cputype does.\n\nThe  same  values for -mcpu=cputype can be used for -mtune=cputype, but the only useful\nvalues are those that  select  a  particular  CPU  implementation.   Those  are  cypress,\nsupersparc,  hypersparc,  leon,  leon3, leon3v7, leon5, f930, f934, sparclite86x, tsc701,\nultrasparc, ultrasparc3, niagara, niagara2, niagara3, niagara4, niagara7  and  m8.   With\nnative Solaris and GNU/Linux toolchains, native can also be used.\n"
                },
                {
                    "name": "-mv8plus",
                    "content": ""
                },
                {
                    "name": "-mno-v8plus",
                    "content": "With  -mv8plus, GCC generates code for the SPARC-V8+ ABI.  The difference from the V8 ABI\nis that the global and out registers are considered 64 bits wide.   This  is  enabled  by\ndefault on Solaris in 32-bit mode for all SPARC-V9 processors.\n"
                },
                {
                    "name": "-mvis",
                    "content": ""
                },
                {
                    "name": "-mno-vis",
                    "content": "With  -mvis, GCC generates code that takes advantage of the UltraSPARC Visual Instruction\nSet extensions.  The default is -mno-vis.\n"
                },
                {
                    "name": "-mvis2",
                    "content": ""
                },
                {
                    "name": "-mno-vis2",
                    "content": "With -mvis2, GCC generates code that takes advantage of version  2.0  of  the  UltraSPARC\nVisual  Instruction  Set  extensions.   The  default  is -mvis2 when targeting a cpu that\nsupports such instructions, such as UltraSPARC-III and later.  Setting -mvis2  also  sets\n-mvis.\n"
                },
                {
                    "name": "-mvis3",
                    "content": ""
                },
                {
                    "name": "-mno-vis3",
                    "content": "With  -mvis3,  GCC  generates  code that takes advantage of version 3.0 of the UltraSPARC\nVisual Instruction Set extensions.  The default is  -mvis3  when  targeting  a  cpu  that\nsupports such instructions, such as niagara-3 and later.  Setting -mvis3 also sets -mvis2\nand -mvis.\n"
                },
                {
                    "name": "-mvis4",
                    "content": ""
                },
                {
                    "name": "-mno-vis4",
                    "content": "With  -mvis4,  GCC  generates  code that takes advantage of version 4.0 of the UltraSPARC\nVisual Instruction Set extensions.  The default is  -mvis4  when  targeting  a  cpu  that\nsupports  such  instructions,  such  as  niagara-7  and  later.  Setting -mvis4 also sets\n-mvis3, -mvis2 and -mvis.\n"
                },
                {
                    "name": "-mvis4b",
                    "content": ""
                },
                {
                    "name": "-mno-vis4b",
                    "content": "With -mvis4b, GCC generates code that takes advantage of version 4.0  of  the  UltraSPARC\nVisual Instruction Set extensions, plus the additional VIS instructions introduced in the\nOracle  SPARC  Architecture  2017.   The  default  is  -mvis4b  when targeting a cpu that\nsupports such instructions, such as m8 and later.   Setting  -mvis4b  also  sets  -mvis4,\n-mvis3, -mvis2 and -mvis.\n"
                },
                {
                    "name": "-mcbcond",
                    "content": ""
                },
                {
                    "name": "-mno-cbcond",
                    "content": "With  -mcbcond,  GCC  generates  code that takes advantage of the UltraSPARC Compare-and-\nBranch-on-Condition instructions.  The default is -mcbcond  when  targeting  a  CPU  that\nsupports such instructions, such as Niagara-4 and later.\n"
                },
                {
                    "name": "-mfmaf",
                    "content": ""
                },
                {
                    "name": "-mno-fmaf",
                    "content": "With -mfmaf, GCC generates code that takes advantage of the UltraSPARC Fused Multiply-Add\nFloating-point  instructions.   The  default is -mfmaf when targeting a CPU that supports\nsuch instructions, such as Niagara-3 and later.\n"
                },
                {
                    "name": "-mfsmuld",
                    "content": ""
                },
                {
                    "name": "-mno-fsmuld",
                    "content": "With -mfsmuld, GCC generates code that takes advantage  of  the  Floating-point  Multiply\nSingle  to  Double  (FsMULd)  instruction.   The default is -mfsmuld when targeting a CPU\nsupporting the architecture versions V8 or V9 with FPU except -mcpu=leon.\n"
                },
                {
                    "name": "-mpopc",
                    "content": ""
                },
                {
                    "name": "-mno-popc",
                    "content": "With -mpopc, GCC generates code that takes advantage of the UltraSPARC  Population  Count\ninstruction.   The  default  is  -mpopc  when  targeting  a  CPU  that  supports  such an\ninstruction, such as Niagara-2 and later.\n"
                },
                {
                    "name": "-msubxc",
                    "content": ""
                },
                {
                    "name": "-mno-subxc",
                    "content": "With -msubxc, GCC generates  code  that  takes  advantage  of  the  UltraSPARC  Subtract-\nExtended-with-Carry  instruction.   The  default  is  -msubxc  when  targeting a CPU that\nsupports such an instruction, such as Niagara-7 and later.\n"
                },
                {
                    "name": "-mfix-at697f",
                    "content": "Enable the documented workaround for the single erratum of  the  Atmel  AT697F  processor\n(which corresponds to erratum #13 of the AT697E processor).\n"
                },
                {
                    "name": "-mfix-ut699",
                    "content": "Enable  the  documented  workarounds  for  the  floating-point  errata and the data cache\nnullify errata of the UT699 processor.\n"
                },
                {
                    "name": "-mfix-ut700",
                    "content": "Enable the documented workaround for the back-to-back store errata  of  the  UT699E/UT700\nprocessor.\n"
                },
                {
                    "name": "-mfix-gr712rc",
                    "content": "Enable  the  documented  workaround  for  the  back-to-back  store  errata of the GR712RC\nprocessor.\n\nThese -m options are supported in addition to the above  on  SPARC-V9  processors  in  64-bit\nenvironments:\n"
                },
                {
                    "name": "-m32",
                    "content": ""
                },
                {
                    "name": "-m64",
                    "content": "Generate  code for a 32-bit or 64-bit environment.  The 32-bit environment sets int, long\nand pointer to 32 bits.  The 64-bit environment sets int to 32 bits and long and  pointer\nto 64 bits.\n"
                },
                {
                    "name": "-mcmodel=_",
                    "content": "Set the code model to one of\n\nmedlow\nThe  Medium/Low  code  model: 64-bit addresses, programs must be linked in the low 32\nbits of memory.  Programs can be statically or dynamically linked.\n\nmedmid\nThe Medium/Middle code model: 64-bit addresses, programs must be linked in the low 44\nbits of memory, the text and data segments must be less than 2GB in size and the data\nsegment must be located within 2GB of the text segment.\n\nmedany\nThe Medium/Anywhere code model: 64-bit addresses, programs may be linked anywhere  in\nmemory, the text and data segments must be less than 2GB in size and the data segment\nmust be located within 2GB of the text segment.\n\nembmedany\nThe  Medium/Anywhere  code model for embedded systems: 64-bit addresses, the text and\ndata segments must be less than  2GB  in  size,  both  starting  anywhere  in  memory\n(determined  at  link  time).  The global register %g4 points to the base of the data\nsegment.  Programs are statically linked and PIC is not supported.\n"
                },
                {
                    "name": "-mmemory-model=_",
                    "content": "Set the memory model in force on the processor to one of\n\ndefault\nThe default memory model for the processor and operating system.\n\nrmo Relaxed Memory Order\n\npso Partial Store Order\n\ntso Total Store Order\n\nsc  Sequential Consistency\n\nThese memory models are formally defined in  Appendix  D  of  the  SPARC-V9  architecture\nmanual, as set in the processor's \"PSTATE.MM\" field.\n"
                },
                {
                    "name": "-mstack-bias",
                    "content": ""
                },
                {
                    "name": "-mno-stack-bias",
                    "content": "With  -mstack-bias, GCC assumes that the stack pointer, and frame pointer if present, are\noffset by -2047 which must be added back when making stack frame references.  This is the\ndefault in 64-bit mode.  Otherwise, assume no such offset is present.\n\nOptions for System V\n\nThese additional options are available on System V Release 4  for  compatibility  with  other\ncompilers on those systems:\n"
                },
                {
                    "name": "-G   -symbolic  -shared",
                    "content": "",
                    "flag": "-G"
                },
                {
                    "name": "-Qy",
                    "content": "directive in the output.\n"
                },
                {
                    "name": "-Qn",
                    "content": ""
                },
                {
                    "name": "-YP,_",
                    "content": "Search the directories dirs, and no others, for libraries specified with -l.\n"
                },
                {
                    "name": "-Ym,_",
                    "content": "Look in the directory dir to find the M4 preprocessor.  The assembler uses this option.\n\nV850 Options\n\nThese -m options are defined for V850 implementations:\n"
                },
                {
                    "name": "-mlong-calls",
                    "content": ""
                },
                {
                    "name": "-mno-long-calls",
                    "content": "Treat all calls as being far away (near).  If calls are  assumed  to  be  far  away,  the\ncompiler  always loads the function's address into a register, and calls indirect through\nthe pointer.\n"
                },
                {
                    "name": "-mno-ep",
                    "content": ""
                },
                {
                    "name": "-mep",
                    "content": "Do not optimize (do optimize) basic blocks that use the same  index  pointer  4  or  more\ntimes  to  copy  pointer  into  the  \"ep\"  register,  and use the shorter \"sld\" and \"sst\"\ninstructions.  The -mep option is on by default if you optimize.\n"
                },
                {
                    "name": "-mno-prolog-function",
                    "content": ""
                },
                {
                    "name": "-mprolog-function",
                    "content": "Do not use (do use) external functions to save and restore registers at the prologue  and\nepilogue  of  a  function.  The external functions are slower, but use less code space if\nmore than one function saves the same number of registers.  The -mprolog-function  option\nis on by default if you optimize.\n"
                },
                {
                    "name": "-mspace",
                    "content": "Try  to  make the code as small as possible.  At present, this just turns on the -mep and\n-mprolog-function options.\n"
                },
                {
                    "name": "-mtda=_",
                    "content": "Put static or global variables whose size is n bytes or less into the tiny data area that\nregister \"ep\" points to.  The tiny data area can hold up to 256 bytes in total (128 bytes\nfor byte references).\n"
                },
                {
                    "name": "-msda=_",
                    "content": "Put static or global variables whose size is n bytes or less into  the  small  data  area\nthat register \"gp\" points to.  The small data area can hold up to 64 kilobytes.\n"
                },
                {
                    "name": "-mzda=_",
                    "content": "Put  static or global variables whose size is n bytes or less into the first 32 kilobytes\nof memory.\n"
                },
                {
                    "name": "-mv850",
                    "content": "Specify that the target processor is the V850.\n"
                },
                {
                    "name": "-mv850e3v5",
                    "content": "Specify  that  the  target  processor  is  the  V850E3V5.   The   preprocessor   constant\n\"v850e3v5\" is defined if this option is used.\n"
                },
                {
                    "name": "-mv850e2v4",
                    "content": "Specify  that  the target processor is the V850E3V5.  This is an alias for the -mv850e3v5\noption.\n"
                },
                {
                    "name": "-mv850e2v3",
                    "content": "Specify  that  the  target  processor  is  the  V850E2V3.   The   preprocessor   constant\n\"v850e2v3\" is defined if this option is used.\n"
                },
                {
                    "name": "-mv850e2",
                    "content": "Specify  that the target processor is the V850E2.  The preprocessor constant \"v850e2\"\nis defined if this option is used.\n"
                },
                {
                    "name": "-mv850e1",
                    "content": "Specify that the target processor is the V850E1.  The preprocessor constants \"v850e1\"\nand \"v850e\" are defined if this option is used.\n"
                },
                {
                    "name": "-mv850es",
                    "content": "Specify that the target processor is the V850ES.  This  is  an  alias  for  the  -mv850e1\noption.\n"
                },
                {
                    "name": "-mv850e",
                    "content": "Specify that the target processor is the V850E.  The preprocessor constant \"v850e\" is\ndefined if this option is used.\n\nIf neither -mv850 nor -mv850e nor -mv850e1 nor -mv850e2 nor -mv850e2v3 nor -mv850e3v5 are\ndefined then a default target processor is chosen and the relevant v850* preprocessor\nconstant is defined.\n\nThe  preprocessor  constants  \"v850\"  and  \"v851\" are always defined, regardless of\nwhich processor variant is the target.\n"
                },
                {
                    "name": "-mdisable-callt",
                    "content": ""
                },
                {
                    "name": "-mno-disable-callt",
                    "content": "This option suppresses generation of the  \"CALLT\"  instruction  for  the  v850e,  v850e1,\nv850e2, v850e2v3 and v850e3v5 flavors of the v850 architecture.\n\nThis  option  is  enabled  by default when the RH850 ABI is in use (see -mrh850-abi), and\ndisabled by default when the GCC ABI is  in  use.   If  \"CALLT\"  instructions  are  being\ngenerated then the C preprocessor symbol \"V850CALLT\" is defined.\n"
                },
                {
                    "name": "-mrelax",
                    "content": ""
                },
                {
                    "name": "-mno-relax",
                    "content": "Pass on (or do not pass on) the -mrelax command-line option to the assembler.\n"
                },
                {
                    "name": "-mlong-jumps",
                    "content": ""
                },
                {
                    "name": "-mno-long-jumps",
                    "content": "Disable (or re-enable) the generation of PC-relative jump instructions.\n"
                },
                {
                    "name": "-msoft-float",
                    "content": ""
                },
                {
                    "name": "-mhard-float",
                    "content": "Disable  (or  re-enable)  the  generation  of hardware floating point instructions.  This\noption is only significant when the  target  architecture  is  V850E2V3  or  higher.   If\nhardware  floating  point instructions are being generated then the C preprocessor symbol\n\"FPUOK\" is defined, otherwise the symbol \"NOFPU\" is defined.\n"
                },
                {
                    "name": "-mloop",
                    "content": "Enables the use of the e3v5 LOOP instruction.  The use of this instruction is not enabled\nby default when the e3v5 architecture is selected because its use is still experimental.\n"
                },
                {
                    "name": "-mrh850-abi",
                    "content": ""
                },
                {
                    "name": "-mghs",
                    "content": "Enables support for the RH850 version of the V850 ABI.  This is the default.   With  this\nversion of the ABI the following rules apply:\n\n*   Integer  sized  structures and unions are returned via a memory pointer rather than a\nregister.\n\n*   Large structures and unions (more than 8 bytes in size) are passed by value.\n\n*   Functions are aligned to 16-bit boundaries.\n\n*   The -m8byte-align command-line option is supported.\n\n*   The   -mdisable-callt   command-line   option   is   enabled   by    default.     The\n-mno-disable-callt command-line option is not supported.\n\nWhen this version of the ABI is enabled the C preprocessor symbol \"V850RH850ABI\" is\ndefined.\n"
                },
                {
                    "name": "-mgcc-abi",
                    "content": "Enables  support  for  the old GCC version of the V850 ABI.  With this version of the ABI\nthe following rules apply:\n\n*   Integer sized structures and unions are returned in register \"r10\".\n\n*   Large structures and unions (more than 8 bytes in size) are passed by reference.\n\n*   Functions are aligned to 32-bit boundaries, unless optimizing for size.\n\n*   The -m8byte-align command-line option is not supported.\n\n*   The -mdisable-callt command-line option is supported but not enabled by default.\n\nWhen this version of the ABI is enabled the C preprocessor symbol  \"V850GCCABI\"  is\ndefined.\n"
                },
                {
                    "name": "-m8byte-align",
                    "content": ""
                },
                {
                    "name": "-mno-8byte-align",
                    "content": "Enables  support  for  \"double\" and \"long long\" types to be aligned on 8-byte boundaries.\nThe default is to restrict the alignment  of  all  objects  to  at  most  4-bytes.   When\n-m8byte-align is in effect the C preprocessor symbol \"V8508BYTEALIGN\" is defined.\n"
                },
                {
                    "name": "-mbig-switch",
                    "content": "Generate   code   suitable   for  big  switch  tables.   Use  this  option  only  if  the\nassembler/linker complain about out of range branches within a switch table.\n"
                },
                {
                    "name": "-mapp-regs",
                    "content": "This option causes r2 and r5 to be used in the code  generated  by  the  compiler.   This\nsetting is the default.\n"
                },
                {
                    "name": "-mno-app-regs",
                    "content": "This option causes r2 and r5 to be treated as fixed registers.\n\nVAX Options\n\nThese -m options are defined for the VAX:\n"
                },
                {
                    "name": "-munix",
                    "content": "Do  not output certain jump instructions (\"aobleq\" and so on) that the Unix assembler for\nthe VAX cannot handle across long ranges.\n"
                },
                {
                    "name": "-mgnu",
                    "content": "Do output those jump instructions, on the assumption that  the  GNU  assembler  is  being\nused.\n"
                },
                {
                    "name": "-mg",
                    "content": ""
                },
                {
                    "name": "-mlra",
                    "content": ""
                },
                {
                    "name": "-mno-lra",
                    "content": "Enable  Local Register Allocation.  This is still experimental for the VAX, so by default\nthe compiler uses standard reload.\n\nVisium Options\n"
                },
                {
                    "name": "-mdebug",
                    "content": "A program which performs file I/O and is destined to run  on  an  MCM  target  should  be\nlinked  with  this  option.   It causes the libraries libc.a and libdebug.a to be linked.\nThe program should be run on the target under the control of  the  GDB  remote  debugging\nstub.\n"
                },
                {
                    "name": "-msim",
                    "content": "A  program  which  performs  file  I/O  and is destined to run on the simulator should be\nlinked with option.  This causes libraries libc.a and libsim.a to be linked.\n"
                },
                {
                    "name": "-mfpu",
                    "content": ""
                },
                {
                    "name": "-mhard-float",
                    "content": "Generate code containing floating-point instructions.  This is the default.\n"
                },
                {
                    "name": "-mno-fpu",
                    "content": ""
                },
                {
                    "name": "-msoft-float",
                    "content": "Generate code containing library calls for floating-point.\n\n-msoft-float changes the calling convention in the output file;  therefore,  it  is  only\nuseful  if  you  compile  all  of a program with this option.  In particular, you need to\ncompile libgcc.a, the library that comes with GCC, with -msoft-float in order for this to\nwork.\n"
                },
                {
                    "name": "-mcpu=_",
                    "content": "Set the instruction set, register set, and instruction scheduling parameters for  machine\ntype cputype.  Supported values for cputype are mcm, gr5 and gr6.\n\nmcm is a synonym of gr5 present for backward compatibility.\n\nBy  default  (unless configured otherwise), GCC generates code for the GR5 variant of the\nVisium architecture.\n\nWith -mcpu=gr6, GCC generates code for the GR6 variant of the Visium  architecture.   The\nonly difference from GR5 code is that the compiler will generate block move instructions.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "Set  the  instruction scheduling parameters for machine type cputype, but do not set the\ninstruction set or register set that the option -mcpu=cputype would.\n"
                },
                {
                    "name": "-msv-mode",
                    "content": "Generate code for the supervisor mode, where there are no restrictions on the  access  to\ngeneral registers.  This is the default.\n"
                },
                {
                    "name": "-muser-mode",
                    "content": "Generate code for the user mode, where the access to some general registers is forbidden:\non  the  GR5,  registers  r24  to  r31  cannot be accessed in this mode; on the GR6, only\nregisters r29 to r31 are affected.\n\nVMS Options\n\nThese -m options are defined for the VMS implementations:\n"
                },
                {
                    "name": "-mvms-return-codes",
                    "content": "Return VMS condition codes from \"main\". The default is to  return  POSIX-style  condition\n(e.g. error) codes.\n"
                },
                {
                    "name": "-mdebug-main=_",
                    "content": "Flag  the  first  routine  whose  name  starts  with  prefix  as the main routine for the\ndebugger.\n"
                },
                {
                    "name": "-mmalloc64",
                    "content": "Default to 64-bit memory allocation routines.\n"
                },
                {
                    "name": "-mpointer-size=_",
                    "content": "Set the default size of pointers. Possible options for size are 32 or short  for  32  bit\npointers,  64  or  long  for 64 bit pointers, and no for supporting only 32 bit pointers.\nThe later option disables \"pragma pointersize\".\n\nVxWorks Options\n\nThe options in this section are defined for all VxWorks targets.   Options  specific  to  the\ntarget hardware are listed with the other options for that target.\n"
                },
                {
                    "name": "-mrtp",
                    "content": "GCC  can  generate  code  for  both VxWorks kernels and real time processes (RTPs).  This\noption switches from the former to the latter.  It also defines  the  preprocessor  macro\n\"RTP\".\n"
                },
                {
                    "name": "-non-static",
                    "content": "Link  an  RTP  executable  against  shared  libraries  rather than static libraries.  The\noptions -static and -shared can also be used for RTPs; -static is the default.\n"
                },
                {
                    "name": "-Bstatic",
                    "content": ""
                },
                {
                    "name": "-Bdynamic",
                    "content": "These options are passed down to the linker.  They are  defined  for  compatibility  with\nDiab.\n"
                },
                {
                    "name": "-Xbind-lazy",
                    "content": "Enable  lazy  binding  of function calls.  This option is equivalent to -Wl,-z,now and is\ndefined for compatibility with Diab.\n"
                },
                {
                    "name": "-Xbind-now",
                    "content": "Disable lazy binding of function calls.  This option is the default and  is  defined  for\ncompatibility with Diab.\n\nx86 Options\n\nThese -m options are defined for the x86 family of computers.\n"
                },
                {
                    "name": "-march=_",
                    "content": "Generate  instructions  for  the  machine type cpu-type.  In contrast to -mtune=cpu-type,\nwhich merely tunes the generated code for the specified cpu-type, -march=cpu-type  allows\nGCC  to generate code that may not run at all on processors other than the one indicated.\nSpecifying -march=cpu-type implies -mtune=cpu-type, except where noted otherwise.\n\nThe choices for cpu-type are:\n\nnative\nThis selects the CPU to generate code for at  compilation  time  by  determining  the\nprocessor type of the compiling machine.  Using -march=native enables all instruction\nsubsets  supported  by the local machine (hence the result might not run on different\nmachines).  Using -mtune=native produces code optimized for the local  machine  under\nthe constraints of the selected instruction set.\n\nx86-64\nA generic CPU with 64-bit extensions.\n\nx86-64-v2\nx86-64-v3\nx86-64-v4\nThese choices for cpu-type select the corresponding micro-architecture level from the\nx86-64  psABI.  On ABIs other than the x86-64 psABI they select the same CPU features\nas the x86-64 psABI documents for the particular micro-architecture level.\n\nSince these cpu-type values do not have a corresponding -mtune setting, using  -march\nwith  these  values enables generic tuning.  Specific tuning can be enabled using the\n-mtune=other-cpu-type option with an appropriate other-cpu-type value.\n\ni386\nOriginal Intel i386 CPU.\n\ni486\nIntel i486 CPU.  (No scheduling is implemented for this chip.)\n\ni586\npentium\nIntel Pentium CPU with no MMX support.\n\nlakemont\nIntel Lakemont MCU, based on Intel Pentium CPU.\n\npentium-mmx\nIntel Pentium MMX CPU, based on Pentium core with MMX instruction set support.\n\npentiumpro\nIntel Pentium Pro CPU.\n\ni686\nWhen used with -march, the Pentium Pro instruction set is used, so the code  runs  on\nall i686 family chips.  When used with -mtune, it has the same meaning as generic.\n\npentium2\nIntel  Pentium  II  CPU,  based on Pentium Pro core with MMX and FXSR instruction set\nsupport.\n\npentium3\npentium3m\nIntel Pentium III CPU, based on Pentium Pro core with MMX, FXSR and  SSE  instruction\nset support.\n\npentium-m\nIntel  Pentium  M; low-power version of Intel Pentium III CPU with MMX, SSE, SSE2 and\nFXSR instruction set support.  Used by Centrino notebooks.\n\npentium4\npentium4m\nIntel Pentium 4 CPU with MMX, SSE, SSE2 and FXSR instruction set support.\n\nprescott\nImproved version of  Intel  Pentium  4  CPU  with  MMX,  SSE,  SSE2,  SSE3  and  FXSR\ninstruction set support.\n\nnocona\nImproved  version of Intel Pentium 4 CPU with 64-bit extensions, MMX, SSE, SSE2, SSE3\nand FXSR instruction set support.\n\ncore2\nIntel Core 2 CPU with 64-bit extensions, MMX, SSE, SSE2, SSE3, SSSE3, CX16, SAHF  and\nFXSR instruction set support.\n\nnehalem\nIntel  Nehalem  CPU  with  64-bit  extensions,  MMX,  SSE, SSE2, SSE3, SSSE3, SSE4.1,\nSSE4.2, POPCNT, CX16, SAHF and FXSR instruction set support.\n\nwestmere\nIntel Westmere CPU with 64-bit extensions,  MMX,  SSE,  SSE2,  SSE3,  SSSE3,  SSE4.1,\nSSE4.2, POPCNT, CX16, SAHF, FXSR and PCLMUL instruction set support.\n\nsandybridge\nIntel  Sandy  Bridge CPU with 64-bit extensions, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1,\nSSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE and PCLMUL instruction set support.\n\nivybridge\nIntel Ivy Bridge CPU with 64-bit extensions, MMX, SSE,  SSE2,  SSE3,  SSSE3,  SSE4.1,\nSSE4.2,  POPCNT,  CX16,  SAHF,  FXSR,  AVX,  XSAVE,  PCLMUL, FSGSBASE, RDRND and F16C\ninstruction set support.\n\nhaswell\nIntel Haswell CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1,\nSSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE,  RDRND,  F16C,  AVX2,\nBMI, BMI2, LZCNT, FMA, MOVBE and HLE instruction set support.\n\nbroadwell\nIntel  Broadwell  CPU  with  64-bit  extensions,  MOVBE, MMX, SSE, SSE2, SSE3, SSSE3,\nSSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND,  F16C,\nAVX2,  BMI,  BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX and PREFETCHW instruction set\nsupport.\n\nskylake\nIntel Skylake CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1,\nSSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE,  RDRND,  F16C,  AVX2,\nBMI,  BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AES, CLFLUSHOPT, XSAVEC,\nXSAVES and SGX instruction set support.\n\nbonnell\nIntel Bonnell CPU with 64-bit extensions, MOVBE,  MMX,  SSE,  SSE2,  SSE3  and  SSSE3\ninstruction set support.\n\nsilvermont\nIntel  Silvermont  CPU  with  64-bit  extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3,\nSSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, PCLMUL, PREFETCHW and RDRND instruction set\nsupport.\n\ngoldmont\nIntel Goldmont CPU with 64-bit  extensions,  MOVBE,  MMX,  SSE,  SSE2,  SSE3,  SSSE3,\nSSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, PCLMUL, PREFETCHW, RDRND, AES, SHA, RDSEED,\nXSAVE, XSAVEC, XSAVES, XSAVEOPT, CLFLUSHOPT and FSGSBASE instruction set support.\n\ngoldmont-plus\nIntel  Goldmont  Plus CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3,\nSSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, PCLMUL, PREFETCHW, RDRND, AES, SHA, RDSEED,\nXSAVE, XSAVEC,  XSAVES,  XSAVEOPT,  CLFLUSHOPT,  FSGSBASE,  PTWRITE,  RDPID  and  SGX\ninstruction set support.\n\ntremont\nIntel Tremont CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1,\nSSE4.2,  POPCNT, CX16, SAHF, FXSR, PCLMUL, PREFETCHW, RDRND, AES, SHA, RDSEED, XSAVE,\nXSAVEC, XSAVES, XSAVEOPT, CLFLUSHOPT, FSGSBASE, PTWRITE, RDPID, SGX, CLWB,  GFNI-SSE,\nMOVDIRI, MOVDIR64B, CLDEMOTE and WAITPKG instruction set support.\n\nsierraforest\nIntel  Sierra  Forest CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3,\nSSE4.1, SSE4.2,  POPCNT,  AES,  PREFETCHW,  PCLMUL,  RDRND,  XSAVE,  XSAVEC,  XSAVES,\nXSAVEOPT,   FSGSBASE,  PTWRITE,  RDPID,  SGX,  GFNI-SSE,  CLWB,  MOVDIRI,  MOVDIR64B,\nCLDEMOTE, WAITPKG, ADCX, AVX, AVX2, BMI, BMI2, F16C, FMA, LZCNT, PCONFIG, PKU,  VAES,\nVPCLMULQDQ,   SERIALIZE,   HRESET,   KL,   WIDEKL,  AVX-VNNI,  AVXIFMA,  AVXVNNIINT8,\nAVXNECONVERT, CMPCCXADD, ENQCMD and UINTR instruction set support.\n\ngrandridge\nIntel Grand Ridge CPU with 64-bit extensions, MOVBE, MMX,  SSE,  SSE2,  SSE3,  SSSE3,\nSSE4.1,  SSE4.2,  POPCNT,  AES,  PREFETCHW,  PCLMUL,  RDRND,  XSAVE,  XSAVEC, XSAVES,\nXSAVEOPT,  FSGSBASE,  PTWRITE,  RDPID,  SGX,  GFNI-SSE,  CLWB,  MOVDIRI,   MOVDIR64B,\nCLDEMOTE,  WAITPKG, ADCX, AVX, AVX2, BMI, BMI2, F16C, FMA, LZCNT, PCONFIG, PKU, VAES,\nVPCLMULQDQ,  SERIALIZE,  HRESET,  KL,   WIDEKL,   AVX-VNNI,   AVXIFMA,   AVXVNNIINT8,\nAVXNECONVERT, CMPCCXADD, ENQCMD and UINTR instruction set support.\n\nknl Intel  Knight's  Landing  CPU  with  64-bit  extensions, MOVBE, MMX, SSE, SSE2, SSE3,\nSSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND,\nF16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE,  RDSEED,  ADCX,  PREFETCHW,  AVX512PF,\nAVX512ER, AVX512F, AVX512CD and PREFETCHWT1 instruction set support.\n\nknm Intel  Knights  Mill  CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3,\nSSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND,  F16C,\nAVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AVX512PF, AVX512ER,\nAVX512F,  AVX512CD  and  PREFETCHWT1,  AVX5124VNNIW, AVX5124FMAPS and AVX512VPOPCNTDQ\ninstruction set support.\n\nskylake-avx512\nIntel Skylake Server CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3,  SSSE3,\nSSE4.1,  SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C,\nAVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX,  PREFETCHW,  AES,  CLFLUSHOPT,\nXSAVEC,  XSAVES,  SGX,  AVX512F,  CLWB,  AVX512VL,  AVX512BW,  AVX512DQ  and AVX512CD\ninstruction set support.\n\ncannonlake\nIntel Cannonlake Server CPU with 64-bit extensions,  MOVBE,  MMX,  SSE,  SSE2,  SSE3,\nSSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND,\nF16C,  AVX2,  BMI,  BMI2,  LZCNT,  FMA,  MOVBE,  HLE,  RDSEED,  ADCX, PREFETCHW, AES,\nCLFLUSHOPT, XSAVEC, XSAVES, SGX, AVX512F,  AVX512VL,  AVX512BW,  AVX512DQ,  AVX512CD,\nPKU, AVX512VBMI, AVX512IFMA and SHA instruction set support.\n\nicelake-client\nIntel  Icelake Client CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3,\nSSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND,  F16C,\nAVX2,  BMI,  BMI2,  LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AES, CLFLUSHOPT,\nXSAVEC,  XSAVES,  SGX,  AVX512F,  AVX512VL,  AVX512BW,   AVX512DQ,   AVX512CD,   PKU,\nAVX512VBMI,  AVX512IFMA,  SHA,  AVX512VNNI,  GFNI,  VAES,  AVX512VBMI2  , VPCLMULQDQ,\nAVX512BITALG, RDPID and AVX512VPOPCNTDQ instruction set support.\n\nicelake-server\nIntel Icelake Server CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3,  SSSE3,\nSSE4.1,  SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C,\nAVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX,  PREFETCHW,  AES,  CLFLUSHOPT,\nXSAVEC,   XSAVES,   SGX,   AVX512F,  AVX512VL,  AVX512BW,  AVX512DQ,  AVX512CD,  PKU,\nAVX512VBMI, AVX512IFMA,  SHA,  AVX512VNNI,  GFNI,  VAES,  AVX512VBMI2  ,  VPCLMULQDQ,\nAVX512BITALG,  RDPID,  AVX512VPOPCNTDQ,  PCONFIG,  WBNOINVD  and CLWB instruction set\nsupport.\n\ncascadelake\nIntel Cascadelake CPU with 64-bit extensions, MOVBE, MMX,  SSE,  SSE2,  SSE3,  SSSE3,\nSSE4.1,  SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C,\nAVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX,  PREFETCHW,  AES,  CLFLUSHOPT,\nXSAVEC,  XSAVES,  SGX,  AVX512F,  CLWB,  AVX512VL,  AVX512BW,  AVX512DQ, AVX512CD and\nAVX512VNNI instruction set support.\n\ncooperlake\nIntel cooperlake CPU with 64-bit extensions, MOVBE,  MMX,  SSE,  SSE2,  SSE3,  SSSE3,\nSSE4.1,  SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C,\nAVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX,  PREFETCHW,  AES,  CLFLUSHOPT,\nXSAVEC,   XSAVES,   SGX,  AVX512F,  CLWB,  AVX512VL,  AVX512BW,  AVX512DQ,  AVX512CD,\nAVX512VNNI and AVX512BF16 instruction set support.\n\ntigerlake\nIntel Tigerlake CPU with 64-bit extensions,  MOVBE,  MMX,  SSE,  SSE2,  SSE3,  SSSE3,\nSSE4.1,  SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C,\nAVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX,  PREFETCHW,  AES,  CLFLUSHOPT,\nXSAVEC, XSAVES, SGX, AVX512F, AVX512VL, AVX512BW, AVX512DQ, AVX512CD PKU, AVX512VBMI,\nAVX512IFMA,  SHA,  AVX512VNNI,  GFNI,  VAES,  AVX512VBMI2,  VPCLMULQDQ, AVX512BITALG,\nRDPID, AVX512VPOPCNTDQ, MOVDIRI, MOVDIR64B, CLWB,  AVX512VP2INTERSECT  and  KEYLOCKER\ninstruction set support.\n\nsapphirerapids\nIntel  sapphirerapids CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3,\nSSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND,  F16C,\nAVX2,  BMI,  BMI2,  LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AES, CLFLUSHOPT,\nXSAVEC,  XSAVES,  SGX,  AVX512F,  AVX512VL,  AVX512BW,   AVX512DQ,   AVX512CD,   PKU,\nAVX512VBMI,   AVX512IFMA,  SHA,  AVX512VNNI,  GFNI,  VAES,  AVX512VBMI2,  VPCLMULQDQ,\nAVX512BITALG, RDPID, AVX512VPOPCNTDQ, PCONFIG, WBNOINVD,  CLWB,  MOVDIRI,  MOVDIR64B,\nENQCMD,  CLDEMOTE,  PTWRITE, WAITPKG, SERIALIZE, TSXLDTRK, UINTR, AMX-BF16, AMX-TILE,\nAMX-INT8, AVX-VNNI, AVX512-FP16 and AVX512BF16 instruction set support.\n\nalderlake\nIntel Alderlake CPU with 64-bit extensions,  MOVBE,  MMX,  SSE,  SSE2,  SSE3,  SSSE3,\nSSE4.1,  SSE4.2,  POPCNT,  AES,  PREFETCHW,  PCLMUL,  RDRND,  XSAVE,  XSAVEC, XSAVES,\nXSAVEOPT,  FSGSBASE,  PTWRITE,  RDPID,  SGX,  GFNI-SSE,  CLWB,  MOVDIRI,   MOVDIR64B,\nCLDEMOTE,  WAITPKG, ADCX, AVX, AVX2, BMI, BMI2, F16C, FMA, LZCNT, PCONFIG, PKU, VAES,\nVPCLMULQDQ, SERIALIZE, HRESET, KL, WIDEKL and AVX-VNNI instruction set support.\n\nrocketlake\nIntel Rocketlake CPU with 64-bit extensions, MOVBE, MMX, SSE,  SSE2,  SSE3,  SSSE3  ,\nSSE4.1,  SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C,\nAVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX,  PREFETCHW,  AES,  CLFLUSHOPT,\nXSAVEC,  XSAVES,  AVX512F,  AVX512VL,  AVX512BW,  AVX512DQ, AVX512CD PKU, AVX512VBMI,\nAVX512IFMA, SHA, AVX512VNNI, GFNI, VAES, AVX512VBMI2, VPCLMULQDQ, AVX512BITALG, RDPID\nand AVX512VPOPCNTDQ instruction set support.\n\ngraniterapids\nIntel graniterapids CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2,  SSE3,  SSSE3,\nSSE4.1,  SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C,\nAVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX,  PREFETCHW,  AES,  CLFLUSHOPT,\nXSAVEC,   XSAVES,   SGX,   AVX512F,  AVX512VL,  AVX512BW,  AVX512DQ,  AVX512CD,  PKU,\nAVX512VBMI,  AVX512IFMA,  SHA,  AVX512VNNI,  GFNI,  VAES,  AVX512VBMI2,   VPCLMULQDQ,\nAVX512BITALG,  RDPID,  AVX512VPOPCNTDQ,  PCONFIG, WBNOINVD, CLWB, MOVDIRI, MOVDIR64B,\nENQCMD, CLDEMOTE, PTWRITE, WAITPKG, SERIALIZE, TSXLDTRK, UINTR,  AMX-BF16,  AMX-TILE,\nAMX-INT8,  AVX-VNNI,  AVX512-FP16, AVX512BF16, AMX-FP16 and PREFETCHI instruction set\nsupport.\n\ngraniterapids-d\nIntel graniterapids D CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3,\nSSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND,  F16C,\nAVX2,  BMI,  BMI2,  LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AES, CLFLUSHOPT,\nXSAVEC,  XSAVES,  SGX,  AVX512F,  AVX512VL,  AVX512BW,   AVX512DQ,   AVX512CD,   PKU,\nAVX512VBMI,   AVX512IFMA,  SHA,  AVX512VNNI,  GFNI,  VAES,  AVX512VBMI2,  VPCLMULQDQ,\nAVX512BITALG, RDPID, AVX512VPOPCNTDQ, PCONFIG, WBNOINVD,  CLWB,  MOVDIRI,  MOVDIR64B,\nENQCMD,  CLDEMOTE,  PTWRITE, WAITPKG, SERIALIZE, TSXLDTRK, UINTR, AMX-BF16, AMX-TILE,\nAMX-INT8, AVX-VNNI,  AVX512FP16,  AVX512BF16,  AMX-FP16,  PREFETCHI  and  AMX-COMPLEX\ninstruction set support.\n\nk6  AMD K6 CPU with MMX instruction set support.\n\nk6-2\nk6-3\nImproved versions of AMD K6 CPU with MMX and 3DNow! instruction set support.\n\nathlon\nathlon-tbird\nAMD  Athlon  CPU  with  MMX,  3dNOW!,  enhanced  3DNow! and SSE prefetch instructions\nsupport.\n\nathlon-4\nathlon-xp\nathlon-mp\nImproved AMD Athlon CPU with MMX, 3DNow!, enhanced 3DNow! and  full  SSE  instruction\nset support.\n\nk8\nopteron\nathlon64\nathlon-fx\nProcessors  based  on  the AMD K8 core with x86-64 instruction set support, including\nthe AMD Opteron, Athlon 64, and Athlon 64 FX processors.  (This supersets  MMX,  SSE,\nSSE2, 3DNow!, enhanced 3DNow! and 64-bit instruction set extensions.)\n\nk8-sse3\nopteron-sse3\nathlon64-sse3\nImproved versions of AMD K8 cores with SSE3 instruction set support.\n\namdfam10\nbarcelona\nCPUs  based  on  AMD  Family  10h  cores  with x86-64 instruction set support.  (This\nsupersets MMX, SSE, SSE2, SSE3,  SSE4A,  3DNow!,  enhanced  3DNow!,  ABM  and  64-bit\ninstruction set extensions.)\n\nbdver1\nCPUs  based  on  AMD  Family  15h  cores  with x86-64 instruction set support.  (This\nsupersets FMA4, AVX, XOP, LWP, AES, PCLMUL, CX16, MMX, SSE, SSE2, SSE3, SSE4A, SSSE3,\nSSE4.1, SSE4.2, ABM and 64-bit instruction set extensions.)\n\nbdver2\nAMD Family 15h core based CPUs with x86-64 instruction set support.  (This  supersets\nBMI,  TBM,  F16C,  FMA, FMA4, AVX, XOP, LWP, AES, PCLMUL, CX16, MMX, SSE, SSE2, SSE3,\nSSE4A, SSSE3, SSE4.1, SSE4.2, ABM and 64-bit instruction set extensions.)\n\nbdver3\nAMD Family 15h core based CPUs with x86-64 instruction set support.  (This  supersets\nBMI,  TBM,  F16C,  FMA,  FMA4,  FSGSBASE, AVX, XOP, LWP, AES, PCLMUL, CX16, MMX, SSE,\nSSE2, SSE3, SSE4A, SSSE3, SSE4.1, SSE4.2, ABM and 64-bit instruction set extensions.)\n\nbdver4\nAMD Family 15h core based CPUs with x86-64 instruction set support.  (This  supersets\nBMI,  BMI2,  TBM,  F16C, FMA, FMA4, FSGSBASE, AVX, AVX2, XOP, LWP, AES, PCLMUL, CX16,\nMOVBE, MMX, SSE, SSE2, SSE3, SSE4A, SSSE3, SSE4.1, SSE4.2, ABM and 64-bit instruction\nset extensions.)\n\nznver1\nAMD Family 17h core based CPUs with x86-64 instruction set support.  (This  supersets\nBMI,  BMI2,  F16C,  FMA, FSGSBASE, AVX, AVX2, ADCX, RDSEED, MWAITX, SHA, CLZERO, AES,\nPCLMUL, CX16, MOVBE, MMX, SSE, SSE2, SSE3, SSE4A, SSSE3, SSE4.1, SSE4.2, ABM, XSAVEC,\nXSAVES, CLFLUSHOPT, POPCNT, and 64-bit instruction set extensions.)\n\nznver2\nAMD Family 17h core based CPUs with x86-64 instruction set support.  (This  supersets\nBMI,  BMI2,  CLWB, F16C, FMA, FSGSBASE, AVX, AVX2, ADCX, RDSEED, MWAITX, SHA, CLZERO,\nAES, PCLMUL, CX16, MOVBE, MMX, SSE, SSE2, SSE3, SSE4A, SSSE3,  SSE4.1,  SSE4.2,  ABM,\nXSAVEC,  XSAVES,  CLFLUSHOPT,  POPCNT,  RDPID,  WBNOINVD,  and 64-bit instruction set\nextensions.)\n\nznver3\nAMD Family 19h core based CPUs with x86-64 instruction set support.  (This  supersets\nBMI,  BMI2,  CLWB, F16C, FMA, FSGSBASE, AVX, AVX2, ADCX, RDSEED, MWAITX, SHA, CLZERO,\nAES, PCLMUL, CX16, MOVBE, MMX, SSE, SSE2, SSE3, SSE4A, SSSE3,  SSE4.1,  SSE4.2,  ABM,\nXSAVEC,  XSAVES,  CLFLUSHOPT,  POPCNT,  RDPID,  WBNOINVD,  PKU, VPCLMULQDQ, VAES, and\n64-bit instruction set extensions.)\n\nznver4\nAMD Family 19h core based CPUs with x86-64 instruction set support.  (This  supersets\nBMI,  BMI2,  CLWB, F16C, FMA, FSGSBASE, AVX, AVX2, ADCX, RDSEED, MWAITX, SHA, CLZERO,\nAES, PCLMUL, CX16, MOVBE, MMX, SSE, SSE2, SSE3, SSE4A, SSSE3,  SSE4.1,  SSE4.2,  ABM,\nXSAVEC,  XSAVES, CLFLUSHOPT, POPCNT, RDPID, WBNOINVD, PKU, VPCLMULQDQ, VAES, AVX512F,\nAVX512DQ,  AVX512IFMA,  AVX512CD,   AVX512BW,   AVX512VL,   AVX512BF16,   AVX512VBMI,\nAVX512VBMI2,  AVX512VNNI,  AVX512BITALG, AVX512VPOPCNTDQ, GFNI and 64-bit instruction\nset extensions.)\n\nbtver1\nCPUs based on AMD Family 14h  cores  with  x86-64  instruction  set  support.   (This\nsupersets  MMX,  SSE,  SSE2, SSE3, SSSE3, SSE4A, CX16, ABM and 64-bit instruction set\nextensions.)\n\nbtver2\nCPUs based on AMD Family 16h cores with x86-64 instruction set support. This includes\nMOVBE, F16C, BMI, AVX, PCLMUL, AES, SSE4.2, SSE4.1, CX16, ABM,  SSE4A,  SSSE3,  SSE3,\nSSE2, SSE, MMX and 64-bit instruction set extensions.\n\nwinchip-c6\nIDT  WinChip  C6  CPU,  dealt in same way as i486 with additional MMX instruction set\nsupport.\n\nwinchip2\nIDT WinChip 2 CPU, dealt  in  same  way  as  i486  with  additional  MMX  and  3DNow!\ninstruction set support.\n\nc3  VIA  C3  CPU  with  MMX  and  3DNow!  instruction  set  support.   (No  scheduling is\nimplemented for this chip.)\n\nc3-2\nVIA C3-2  (Nehemiah/C5XL)  CPU  with  MMX  and  SSE  instruction  set  support.   (No\nscheduling is implemented for this chip.)\n\nc7  VIA  C7  (Esther)  CPU  with  MMX,  SSE,  SSE2 and SSE3 instruction set support.  (No\nscheduling is implemented for this chip.)\n\nsamuel-2\nVIA Eden Samuel 2 CPU with MMX and 3DNow! instruction set support.  (No scheduling is\nimplemented for this chip.)\n\nnehemiah\nVIA Eden Nehemiah CPU with MMX and SSE instruction set support.   (No  scheduling  is\nimplemented for this chip.)\n\nesther\nVIA  Eden  Esther  CPU  with  MMX,  SSE,  SSE2 and SSE3 instruction set support.  (No\nscheduling is implemented for this chip.)\n\neden-x2\nVIA Eden X2 CPU with x86-64, MMX, SSE, SSE2 and SSE3 instruction  set  support.   (No\nscheduling is implemented for this chip.)\n\neden-x4\nVIA  Eden  X4  CPU  with x86-64, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX and\nAVX2 instruction set support.  (No scheduling is implemented for this chip.)\n\nnano\nGeneric VIA Nano CPU with x86-64, MMX, SSE, SSE2,  SSE3  and  SSSE3  instruction  set\nsupport.  (No scheduling is implemented for this chip.)\n\nnano-1000\nVIA  Nano  1xxx  CPU  with  x86-64,  MMX,  SSE,  SSE2, SSE3 and SSSE3 instruction set\nsupport.  (No scheduling is implemented for this chip.)\n\nnano-2000\nVIA Nano 2xxx CPU with x86-64,  MMX,  SSE,  SSE2,  SSE3  and  SSSE3  instruction  set\nsupport.  (No scheduling is implemented for this chip.)\n\nnano-3000\nVIA Nano 3xxx CPU with x86-64, MMX, SSE, SSE2, SSE3, SSSE3 and SSE4.1 instruction set\nsupport.  (No scheduling is implemented for this chip.)\n\nnano-x2\nVIA  Nano  Dual  Core  CPU  with  x86-64,  MMX,  SSE,  SSE2,  SSE3,  SSSE3 and SSE4.1\ninstruction set support.  (No scheduling is implemented for this chip.)\n\nnano-x4\nVIA Nano Quad  Core  CPU  with  x86-64,  MMX,  SSE,  SSE2,  SSE3,  SSSE3  and  SSE4.1\ninstruction set support.  (No scheduling is implemented for this chip.)\n\nlujiazui\nZHAOXIN lujiazui CPU with x86-64, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2,\nAVX,  POPCNT,  AES,  PCLMUL,  RDRND, XSAVE, XSAVEOPT, FSGSBASE, CX16, ABM, BMI, BMI2,\nF16C, FXSR, RDSEED instruction set support.\n\ngeode\nAMD Geode embedded processor with MMX and 3DNow! instruction set support.\n"
                },
                {
                    "name": "-mtune=_",
                    "content": "Tune to cpu-type everything applicable about the generated code, except for the  ABI  and\nthe  set  of  available instructions.  While picking a specific cpu-type schedules things\nappropriately for that particular chip, the compiler does  not  generate  any  code  that\ncannot  run  on  the  default  machine type unless you use a -march=cpu-type option.  For\nexample, if GCC is configured for i686-pc-linux-gnu then -mtune=pentium4  generates  code\nthat is tuned for Pentium 4 but still runs on i686 machines.\n\nThe  choices  for  cpu-type  are  the same as for -march.  In addition, -mtune supports 2\nextra choices for cpu-type:\n\ngeneric\nProduce code optimized for the most common IA32/AMD64/EM64T processors.  If you  know\nthe  CPU on which your code will run, then you should use the corresponding -mtune or\n-march option instead of -mtune=generic.  But, if you do not know  exactly  what  CPU\nusers of your application will have, then you should use this option.\n\nAs  new  processors are deployed in the marketplace, the behavior of this option will\nchange.  Therefore, if you upgrade  to  a  newer  version  of  GCC,  code  generation\ncontrolled  by this option will change to reflect the processors that are most common\nat the time that version of GCC is released.\n\nThere is no -march=generic option because -march indicates the  instruction  set  the\ncompiler  can  use,  and  there  is  no  generic  instruction  set  applicable to all\nprocessors.   In  contrast,  -mtune  indicates  the  processor  (or,  in  this  case,\ncollection of processors) for which the code is optimized.\n\nintel\nProduce  code  optimized for the most current Intel processors, which are Haswell and\nSilvermont for this version of GCC.  If you know the CPU on which your code will run,\nthen  you  should  use  the  corresponding  -mtune  or  -march  option   instead   of\n-mtune=intel.   But, if you want your application performs better on both Haswell and\nSilvermont, then you should use this option.\n\nAs new Intel processors are deployed in the marketplace, the behavior of this  option\nwill  change.   Therefore,  if you upgrade to a newer version of GCC, code generation\ncontrolled by this option will change to reflect the most current Intel processors at\nthe time that version of GCC is released.\n\nThere is no -march=intel option because -march  indicates  the  instruction  set  the\ncompiler  can  use,  and  there  is  no  common  instruction  set  applicable  to all\nprocessors.   In  contrast,  -mtune  indicates  the  processor  (or,  in  this  case,\ncollection of processors) for which the code is optimized.\n"
                },
                {
                    "name": "-mcpu=_",
                    "content": "A deprecated synonym for -mtune.\n"
                },
                {
                    "name": "-mfpmath=_",
                    "content": "Generate floating-point arithmetic for selected unit unit.  The choices for unit are:\n\n387 Use  the standard 387 floating-point coprocessor present on the majority of chips and\nemulated otherwise.  Code compiled with this  option  runs  almost  everywhere.   The\ntemporary results are computed in 80-bit precision instead of the precision specified\nby the type, resulting in slightly different results compared to most of other chips.\nSee -ffloat-store for more detailed description.\n\nThis is the default choice for non-Darwin x86-32 targets.\n\nsse Use  scalar  floating-point  instructions  present  in the SSE instruction set.  This\ninstruction set is supported by Pentium III and newer chips, and in the AMD  line  by\nAthlon-4,  Athlon XP and Athlon MP chips.  The earlier version of the SSE instruction\nset supports only single-precision arithmetic, thus the double and extended-precision\narithmetic are still done using 387.  A later version, present only in Pentium 4  and\nAMD x86-64 chips, supports double-precision arithmetic too.\n\nFor  the  x86-32  compiler, you must use -march=cpu-type, -msse or -msse2 switches to\nenable SSE extensions and make this option effective.  For the x86-64 compiler, these\nextensions are enabled by default.\n\nThe resulting code should be considerably faster in the majority of cases  and  avoid\nthe numerical instability problems of 387 code, but may break some existing code that\nexpects temporaries to be 80 bits.\n\nThis  is  the  default choice for the x86-64 compiler, Darwin x86-32 targets, and the\ndefault choice for x86-32 targets with the SSE2 instruction set when  -ffast-math  is\nenabled.\n\nsse,387\nsse+387\nboth\nAttempt  to  utilize  both  instruction  sets  at once.  This effectively doubles the\namount of available registers, and on chips with separate execution units for 387 and\nSSE the execution resources  too.   Use  this  option  with  care,  as  it  is  still\nexperimental,  because  the GCC register allocator does not model separate functional\nunits well, resulting in unstable performance.\n"
                },
                {
                    "name": "-masm=_",
                    "content": "Output assembly instructions using selected dialect.  Also affects which dialect is  used\nfor  basic  \"asm\"  and  extended  \"asm\".  Supported choices (in dialect order) are att or\nintel. The default is att. Darwin does not support intel.\n"
                },
                {
                    "name": "-mieee-fp",
                    "content": ""
                },
                {
                    "name": "-mno-ieee-fp",
                    "content": "Control whether  or  not  the  compiler  uses  IEEE  floating-point  comparisons.   These\ncorrectly handle the case where the result of a comparison is unordered.\n"
                },
                {
                    "name": "-m80387",
                    "content": ""
                },
                {
                    "name": "-mhard-float",
                    "content": "Generate output containing 80387 instructions for floating point.\n"
                },
                {
                    "name": "-mno-80387",
                    "content": ""
                },
                {
                    "name": "-msoft-float",
                    "content": "Generate output containing library calls for floating point.\n\nWarning:  the  requisite  libraries  are not part of GCC.  Normally the facilities of the\nmachine's usual C compiler  are  used,  but  this  cannot  be  done  directly  in  cross-\ncompilation.   You  must make your own arrangements to provide suitable library functions\nfor cross-compilation.\n\nOn machines where a function returns floating-point results in the 80387 register  stack,\nsome floating-point opcodes may be emitted even if -msoft-float is used.\n"
                },
                {
                    "name": "-mno-fp-ret-in-387",
                    "content": "Do not use the FPU registers for return values of functions.\n\nThe usual calling convention has functions return values of types \"float\" and \"double\" in\nan  FPU  register, even if there is no FPU.  The idea is that the operating system should\nemulate an FPU.\n\nThe option -mno-fp-ret-in-387 causes such values to be returned in ordinary CPU registers\ninstead.\n"
                },
                {
                    "name": "-mno-fancy-math-387",
                    "content": "Some 387 emulators do not support the \"sin\", \"cos\" and \"sqrt\" instructions for  the  387.\nSpecify  this  option  to avoid generating those instructions.  This option is overridden\nwhen -march indicates that the target CPU always has an FPU and so the  instruction  does\nnot  need  emulation.   These  instructions  are  not  generated  unless you also use the\n-funsafe-math-optimizations switch.\n"
                },
                {
                    "name": "-malign-double",
                    "content": ""
                },
                {
                    "name": "-mno-align-double",
                    "content": "Control whether GCC aligns \"double\", \"long double\", and \"long long\" variables on  a  two-\nword boundary or a one-word boundary.  Aligning \"double\" variables on a two-word boundary\nproduces code that runs somewhat faster on a Pentium at the expense of more memory.\n\nOn x86-64, -malign-double is enabled by default.\n\nWarning:  if you use the -malign-double switch, structures containing the above types are\naligned differently than the published application binary  interface  specifications  for\nthe  x86-32  and  are not binary compatible with structures in code compiled without that\nswitch.\n"
                },
                {
                    "name": "-m96bit-long-double",
                    "content": ""
                },
                {
                    "name": "-m128bit-long-double",
                    "content": "These switches control the size of \"long double\" type.   The  x86-32  application  binary\ninterface  specifies  the  size  to  be 96 bits, so -m96bit-long-double is the default in\n32-bit mode.\n\nModern architectures (Pentium and newer) prefer \"long double\" to be aligned to an  8-  or\n16-byte  boundary.   In arrays or structures conforming to the ABI, this is not possible.\nSo specifying -m128bit-long-double aligns \"long double\" to a 16-byte boundary by  padding\nthe \"long double\" with an additional 32-bit zero.\n\nIn  the  x86-64 compiler, -m128bit-long-double is the default choice as its ABI specifies\nthat \"long double\" is aligned on 16-byte boundary.\n\nNotice that neither of these options enable any extra precision over the x87 standard  of\n80 bits for a \"long double\".\n\nWarning:  if you override the default value for your target ABI, this changes the size of\nstructures and arrays containing \"long  double\"  variables,  as  well  as  modifying  the\nfunction  calling  convention  for  functions  taking  \"long double\".  Hence they are not\nbinary-compatible with code compiled without that switch.\n"
                },
                {
                    "name": "-mlong-double-64",
                    "content": ""
                },
                {
                    "name": "-mlong-double-80",
                    "content": ""
                },
                {
                    "name": "-mlong-double-128",
                    "content": "These switches control the size of \"long double\" type. A size of 64 bits makes the  \"long\ndouble\"  type  equivalent  to  the \"double\" type. This is the default for 32-bit Bionic C\nlibrary.  A size of 128 bits makes the \"long double\" type equivalent to the  \"float128\"\ntype. This is the default for 64-bit Bionic C library.\n\nWarning:  if you override the default value for your target ABI, this changes the size of\nstructures and arrays containing \"long  double\"  variables,  as  well  as  modifying  the\nfunction  calling  convention  for  functions  taking  \"long double\".  Hence they are not\nbinary-compatible with code compiled without that switch.\n"
                },
                {
                    "name": "-malign-data=_",
                    "content": "Control how GCC aligns variables.  Supported values for type are  compat  uses  increased\nalignment  value  compatible  uses  GCC  4.8  and  earlier,  abi  uses alignment value as\nspecified by the psABI, and cacheline uses increased alignment value to match  the  cache\nline size.  compat is the default.\n"
                },
                {
                    "name": "-mlarge-data-threshold=_",
                    "content": "When  -mcmodel=medium  is specified, data objects larger than threshold are placed in the\nlarge data section.  This value must be the same  across  all  objects  linked  into  the\nbinary, and defaults to 65535.\n"
                },
                {
                    "name": "-mrtd",
                    "content": "Use  a different function-calling convention, in which functions that take a fixed number\nof arguments return with the \"ret num\" instruction,  which  pops  their  arguments  while\nreturning.   This  saves  one instruction in the caller since there is no need to pop the\narguments there.\n\nYou can specify that an individual function is called with this calling sequence with the\nfunction attribute \"stdcall\".  You can also  override  the  -mrtd  option  by  using  the\nfunction attribute \"cdecl\".\n\nWarning:  this  calling convention is incompatible with the one normally used on Unix, so\nyou cannot use it if you need to call libraries compiled with the Unix compiler.\n\nAlso, you must provide function prototypes for all functions that take  variable  numbers\nof  arguments  (including  \"printf\");  otherwise incorrect code is generated for calls to\nthose functions.\n\nIn addition, seriously incorrect code results if  you  call  a  function  with  too  many\narguments.  (Normally, extra arguments are harmlessly ignored.)\n"
                },
                {
                    "name": "-mregparm=_",
                    "content": "Control  how many registers are used to pass integer arguments.  By default, no registers\nare used to pass arguments, and at most 3 registers can be used.  You  can  control  this\nbehavior for a specific function by using the function attribute \"regparm\".\n\nWarning: if you use this switch, and num is nonzero, then you must build all modules with\nthe  same value, including any libraries.  This includes the system libraries and startup\nmodules.\n"
                },
                {
                    "name": "-msseregparm",
                    "content": "Use SSE register passing conventions for float and double arguments  and  return  values.\nYou  can  control  this  behavior for a specific function by using the function attribute\n\"sseregparm\".\n\nWarning: if you use this switch then you must build all  modules  with  the  same  value,\nincluding any libraries.  This includes the system libraries and startup modules.\n"
                },
                {
                    "name": "-mvect8-ret-in-mem",
                    "content": "Return 8-byte vectors in memory instead of MMX registers.  This is the default on VxWorks\nto  match  the ABI of the Sun Studio compilers until version 12.  Only use this option if\nyou need to remain compatible with existing code  produced  by  those  previous  compiler\nversions or older versions of GCC.\n"
                },
                {
                    "name": "-mpc32",
                    "content": ""
                },
                {
                    "name": "-mpc64",
                    "content": ""
                },
                {
                    "name": "-mpc80",
                    "content": "Set  80387  floating-point precision to 32, 64 or 80 bits.  When -mpc32 is specified, the\nsignificands of results of floating-point operations  are  rounded  to  24  bits  (single\nprecision);  -mpc64 rounds the significands of results of floating-point operations to 53\nbits (double precision) and -mpc80 rounds the significands of results  of  floating-point\noperations  to  64  bits  (extended  double  precision), which is the default.  When this\noption is used, floating-point operations in higher precisions are not available  to  the\nprogrammer without setting the FPU control word explicitly.\n\nSetting  the  rounding  of floating-point operations to less than the default 80 bits can\nspeed some programs by 2% or more.  Note that some  mathematical  libraries  assume  that\nextended-precision (80-bit) floating-point operations are enabled by default; routines in\nsuch  libraries  could  suffer  significant loss of accuracy, typically through so-called\n\"catastrophic cancellation\", when this option is used to set the precision to  less  than\nextended precision.\n"
                },
                {
                    "name": "-mdaz-ftz",
                    "content": "The flush-to-zero (FTZ) and denormals-are-zero (DAZ) flags in the MXCSR register are used\nto  control  floating-point  calculations.SSE  and  AVX instructions including scalar and\nvector instructions could benefit from enabling the FTZ and DAZ flags when  -mdaz-ftz  is\nspecified.  Don't  set FTZ/DAZ flags when -mno-daz-ftz or -shared is specified, -mdaz-ftz\nwill set FTZ/DAZ flags even with -shared.\n"
                },
                {
                    "name": "-mstackrealign",
                    "content": "Realign the stack at entry.  On the x86, the -mstackrealign option generates an alternate\nprologue and epilogue that realigns the  run-time  stack  if  necessary.   This  supports\nmixing  legacy codes that keep 4-byte stack alignment with modern codes that keep 16-byte\nstack alignment for SSE compatibility.  See also the attribute \"forcealignargpointer\",\napplicable to individual functions.\n"
                },
                {
                    "name": "-mpreferred-stack-boundary=_",
                    "content": "Attempt to keep the stack boundary aligned to a  2  raised  to  num  byte  boundary.   If\n-mpreferred-stack-boundary is not specified, the default is 4 (16 bytes or 128 bits).\n\nWarning:  When  generating code for the x86-64 architecture with SSE extensions disabled,\n-mpreferred-stack-boundary=3 can be used to keep the stack boundary  aligned  to  8  byte\nboundary.  Since x86-64 ABI require 16 byte stack alignment, this is ABI incompatible and\nintended  to be used in controlled environment where stack space is important limitation.\nThis option leads to wrong code when functions compiled  with  16  byte  stack  alignment\n(such  as  functions  from a standard library) are called with misaligned stack.  In this\ncase, SSE instructions may lead to misaligned memory access traps.  In addition, variable\narguments are handled incorrectly for 16 byte aligned objects (including x87 long  double\nand   int128),   leading   to   wrong   results.   You  must  build  all  modules  with\n-mpreferred-stack-boundary=3,  including  any  libraries.   This  includes   the   system\nlibraries and startup modules.\n"
                },
                {
                    "name": "-mincoming-stack-boundary=_",
                    "content": "Assume  the  incoming  stack  is  aligned  to  a  2  raised  to  num  byte  boundary.  If\n-mincoming-stack-boundary    is    not    specified,     the     one     specified     by\n-mpreferred-stack-boundary is used.\n\nOn  Pentium  and  Pentium  Pro, \"double\" and \"long double\" values should be aligned to an\n8-byte  boundary  (see  -malign-double)  or  suffer  significant  run  time   performance\npenalties.  On Pentium III, the Streaming SIMD Extension (SSE) data type \"m128\" may not\nwork properly if it is not 16-byte aligned.\n\nTo  ensure  proper  alignment  of this values on the stack, the stack boundary must be as\naligned as that required by any value stored on the stack.  Further, every function  must\nbe generated such that it keeps the stack aligned.  Thus calling a function compiled with\na  higher  preferred stack boundary from a function compiled with a lower preferred stack\nboundary most likely misaligns the stack.  It is  recommended  that  libraries  that  use\ncallbacks always use the default setting.\n\nThis  extra  alignment does consume extra stack space, and generally increases code size.\nCode that is sensitive to stack space usage,  such  as  embedded  systems  and  operating\nsystem     kernels,    may    want    to    reduce    the    preferred    alignment    to\n-mpreferred-stack-boundary=2.\n"
                },
                {
                    "name": "-mmmx",
                    "content": ""
                },
                {
                    "name": "-msse",
                    "content": ""
                },
                {
                    "name": "-msse2",
                    "content": ""
                },
                {
                    "name": "-msse3",
                    "content": ""
                },
                {
                    "name": "-mssse3",
                    "content": ""
                },
                {
                    "name": "-msse4",
                    "content": ""
                },
                {
                    "name": "-msse4a",
                    "content": ""
                },
                {
                    "name": "-msse4.1",
                    "content": ""
                },
                {
                    "name": "-msse4.2",
                    "content": ""
                },
                {
                    "name": "-mavx",
                    "content": ""
                },
                {
                    "name": "-mavx2",
                    "content": ""
                },
                {
                    "name": "-mavx512f",
                    "content": ""
                },
                {
                    "name": "-mavx512pf",
                    "content": ""
                },
                {
                    "name": "-mavx512er",
                    "content": ""
                },
                {
                    "name": "-mavx512cd",
                    "content": ""
                },
                {
                    "name": "-mavx512vl",
                    "content": ""
                },
                {
                    "name": "-mavx512bw",
                    "content": ""
                },
                {
                    "name": "-mavx512dq",
                    "content": ""
                },
                {
                    "name": "-mavx512ifma",
                    "content": ""
                },
                {
                    "name": "-mavx512vbmi",
                    "content": ""
                },
                {
                    "name": "-msha",
                    "content": ""
                },
                {
                    "name": "-maes",
                    "content": ""
                },
                {
                    "name": "-mpclmul",
                    "content": ""
                },
                {
                    "name": "-mclflushopt",
                    "content": ""
                },
                {
                    "name": "-mclwb",
                    "content": ""
                },
                {
                    "name": "-mfsgsbase",
                    "content": ""
                },
                {
                    "name": "-mptwrite",
                    "content": ""
                },
                {
                    "name": "-mrdrnd",
                    "content": ""
                },
                {
                    "name": "-mf16c",
                    "content": ""
                },
                {
                    "name": "-mfma",
                    "content": ""
                },
                {
                    "name": "-mpconfig",
                    "content": ""
                },
                {
                    "name": "-mwbnoinvd",
                    "content": ""
                },
                {
                    "name": "-mfma4",
                    "content": ""
                },
                {
                    "name": "-mprfchw",
                    "content": ""
                },
                {
                    "name": "-mrdpid",
                    "content": ""
                },
                {
                    "name": "-mprefetchwt1",
                    "content": ""
                },
                {
                    "name": "-mrdseed",
                    "content": ""
                },
                {
                    "name": "-msgx",
                    "content": ""
                },
                {
                    "name": "-mxop",
                    "content": ""
                },
                {
                    "name": "-mlwp",
                    "content": ""
                },
                {
                    "name": "-m3dnow",
                    "content": ""
                },
                {
                    "name": "-m3dnowa",
                    "content": ""
                },
                {
                    "name": "-mpopcnt",
                    "content": ""
                },
                {
                    "name": "-mabm",
                    "content": ""
                },
                {
                    "name": "-madx",
                    "content": ""
                },
                {
                    "name": "-mbmi",
                    "content": ""
                },
                {
                    "name": "-mbmi2",
                    "content": ""
                },
                {
                    "name": "-mlzcnt",
                    "content": ""
                },
                {
                    "name": "-mfxsr",
                    "content": ""
                },
                {
                    "name": "-mxsave",
                    "content": ""
                },
                {
                    "name": "-mxsaveopt",
                    "content": ""
                },
                {
                    "name": "-mxsavec",
                    "content": ""
                },
                {
                    "name": "-mxsaves",
                    "content": ""
                },
                {
                    "name": "-mrtm",
                    "content": ""
                },
                {
                    "name": "-mhle",
                    "content": ""
                },
                {
                    "name": "-mtbm",
                    "content": ""
                },
                {
                    "name": "-mmwaitx",
                    "content": ""
                },
                {
                    "name": "-mclzero",
                    "content": ""
                },
                {
                    "name": "-mpku",
                    "content": ""
                },
                {
                    "name": "-mavx512vbmi2",
                    "content": ""
                },
                {
                    "name": "-mavx512bf16",
                    "content": ""
                },
                {
                    "name": "-mavx512fp16",
                    "content": ""
                },
                {
                    "name": "-mgfni",
                    "content": ""
                },
                {
                    "name": "-mvaes",
                    "content": ""
                },
                {
                    "name": "-mwaitpkg",
                    "content": ""
                },
                {
                    "name": "-mvpclmulqdq",
                    "content": ""
                },
                {
                    "name": "-mavx512bitalg",
                    "content": ""
                },
                {
                    "name": "-mmovdiri",
                    "content": ""
                },
                {
                    "name": "-mmovdir64b",
                    "content": ""
                },
                {
                    "name": "-menqcmd",
                    "content": ""
                },
                {
                    "name": "-muintr",
                    "content": ""
                },
                {
                    "name": "-mtsxldtrk",
                    "content": ""
                },
                {
                    "name": "-mavx512vpopcntdq",
                    "content": ""
                },
                {
                    "name": "-mavx512vp2intersect",
                    "content": ""
                },
                {
                    "name": "-mavx5124fmaps",
                    "content": ""
                },
                {
                    "name": "-mavx512vnni",
                    "content": ""
                },
                {
                    "name": "-mavxvnni",
                    "content": ""
                },
                {
                    "name": "-mavx5124vnniw",
                    "content": ""
                },
                {
                    "name": "-mcldemote",
                    "content": ""
                },
                {
                    "name": "-mserialize",
                    "content": ""
                },
                {
                    "name": "-mamx-tile",
                    "content": ""
                },
                {
                    "name": "-mamx-int8",
                    "content": ""
                },
                {
                    "name": "-mamx-bf16",
                    "content": ""
                },
                {
                    "name": "-mhreset",
                    "content": ""
                },
                {
                    "name": "-mkl",
                    "content": ""
                },
                {
                    "name": "-mwidekl",
                    "content": ""
                },
                {
                    "name": "-mavxifma",
                    "content": ""
                },
                {
                    "name": "-mavxvnniint8",
                    "content": ""
                },
                {
                    "name": "-mavxneconvert",
                    "content": ""
                },
                {
                    "name": "-mcmpccxadd",
                    "content": ""
                },
                {
                    "name": "-mamx-fp16",
                    "content": ""
                },
                {
                    "name": "-mprefetchi",
                    "content": ""
                },
                {
                    "name": "-mraoint",
                    "content": ""
                },
                {
                    "name": "-mamx-complex",
                    "content": "These switches enable the use of instructions in the MMX, SSE, SSE2, SSE3,  SSSE3,  SSE4,\nSSE4A,  SSE4.1,  SSE4.2,  AVX,  AVX2,  AVX512F,  AVX512PF,  AVX512ER, AVX512CD, AVX512VL,\nAVX512BW, AVX512DQ, AVX512IFMA, AVX512VBMI, SHA, AES, PCLMUL, CLFLUSHOPT, CLWB, FSGSBASE,\nPTWRITE, RDRND, F16C,  FMA,  PCONFIG,  WBNOINVD,  FMA4,  PREFETCHW,  RDPID,  PREFETCHWT1,\nRDSEED, SGX, XOP, LWP, 3DNow!, enhanced 3DNow!, POPCNT, ABM, ADX, BMI, BMI2, LZCNT, FXSR,\nXSAVE,  XSAVEOPT,  XSAVEC, XSAVES, RTM, HLE, TBM, MWAITX, CLZERO, PKU, AVX512VBMI2, GFNI,\nVAES,  WAITPKG,  VPCLMULQDQ,  AVX512BITALG,  MOVDIRI,  MOVDIR64B,   AVX512BF16,   ENQCMD,\nAVX512VPOPCNTDQ,   AVX5124FMAPS,  AVX512VNNI,  AVX5124VNNIW,  SERIALIZE,  UINTR,  HRESET,\nAMXTILE, AMXINT8,  AMXBF16,  KL,  WIDEKL,  AVXVNNI,  AVX512-FP16,  AVXIFMA,  AVXVNNIINT8,\nAVXNECONVERT,  CMPCCXADD,  AMX-FP16,  PREFETCHI, RAOINT, AMX-COMPLEX or CLDEMOTE extended\ninstruction sets. Each  has  a  corresponding  -mno-  option  to  disable  use  of  these\ninstructions.\n\nThese  extensions  are  also available as built-in functions: see x86 Built-in Functions,\nfor details of the functions enabled and disabled by these switches.\n\nTo generate SSE/SSE2 instructions automatically from floating-point code (as  opposed  to\n387 instructions), see -mfpmath=sse.\n\nGCC  depresses  SSEx  instructions  when  -mavx  is  used.  Instead, it generates new AVX\ninstructions or AVX equivalence for all SSEx instructions when needed.\n\nThese options enable GCC to use these  extended  instructions  in  generated  code,  even\nwithout  -mfpmath=sse.   Applications  that  perform  run-time CPU detection must compile\nseparate files  for  each  supported  architecture,  using  the  appropriate  flags.   In\nparticular,  the  file containing the CPU detection code should be compiled without these\noptions.\n"
                },
                {
                    "name": "-mdump-tune-features",
                    "content": "This option instructs GCC to dump the names of the x86 performance  tuning  features  and\ndefault settings. The names can be used in -mtune-ctrl=feature-list.\n"
                },
                {
                    "name": "-mtune-ctrl=_",
                    "content": "This  option  is used to do fine grain control of x86 code generation features.  feature-\nlist is a comma separated list of feature  names.  See  also  -mdump-tune-features.  When\nspecified, the feature is turned on if it is not preceded with ^, otherwise, it is turned\noff.   -mtune-ctrl=feature-list  is  intended  to be used by GCC developers. Using it may\nlead to code paths not covered by testing and can potentially result in compiler ICEs  or\nruntime errors.\n"
                },
                {
                    "name": "-mno-default",
                    "content": "This option instructs GCC to turn off all tunable features. See also -mtune-ctrl=feature-\nlist and -mdump-tune-features.\n"
                },
                {
                    "name": "-mcld",
                    "content": "This  option  instructs GCC to emit a \"cld\" instruction in the prologue of functions that\nuse string instructions.  String instructions depend on the DF  flag  to  select  between\nautoincrement  or  autodecrement mode.  While the ABI specifies the DF flag to be cleared\non function entry, some operating systems violate this specification by not clearing  the\nDF flag in their exception dispatchers.  The exception handler can be invoked with the DF\nflag  set,  which  leads to wrong direction mode when string instructions are used.  This\noption can be enabled by default on 32-bit  x86  targets  by  configuring  GCC  with  the\n--enable-cld  configure  option.  Generation of \"cld\" instructions can be suppressed with\nthe -mno-cld compiler option in this case.\n"
                },
                {
                    "name": "-mvzeroupper",
                    "content": "This option instructs GCC to emit a \"vzeroupper\" instruction before a transfer of control\nflow out of the function to minimize the AVX to SSE transition penalty as well as  remove\nunnecessary \"zeroupper\" intrinsics.\n"
                },
                {
                    "name": "-mprefer-avx128",
                    "content": "This  option  instructs  GCC  to  use  128-bit  AVX  instructions  instead of 256-bit AVX\ninstructions in the auto-vectorizer.\n"
                },
                {
                    "name": "-mprefer-vector-width=_",
                    "content": "This option instructs GCC to use opt-bit vector width in instructions instead of  default\non the selected platform.\n"
                },
                {
                    "name": "-mmove-max=_",
                    "content": "This  option  instructs GCC to set the maximum number of bits can be moved from memory to\nmemory efficiently to bits.  The valid bits are 128, 256 and 512.\n"
                },
                {
                    "name": "-mstore-max=_",
                    "content": "This option instructs GCC to set the maximum number of  bits  can  be  stored  to  memory\nefficiently to bits.  The valid bits are 128, 256 and 512.\n\nnone\nNo extra limitations applied to GCC other than defined by the selected platform.\n\n128 Prefer 128-bit vector width for instructions.\n\n256 Prefer 256-bit vector width for instructions.\n\n512 Prefer 512-bit vector width for instructions.\n"
                },
                {
                    "name": "-mcx16",
                    "content": "This option enables GCC to generate \"CMPXCHG16B\" instructions in 64-bit code to implement\ncompare-and-exchange  operations  on 16-byte aligned 128-bit objects.  This is useful for\natomic updates of data structures exceeding one machine word in size.  The compiler  uses\nthis  instruction to implement sync Builtins.  However, for atomic Builtins operating\non 128-bit integers, a library call is always used.\n"
                },
                {
                    "name": "-msahf",
                    "content": "This option enables generation of  \"SAHF\"  instructions  in  64-bit  code.   Early  Intel\nPentium  4  CPUs with Intel 64 support, prior to the introduction of Pentium 4 G1 step in\nDecember 2005, lacked the \"LAHF\" and \"SAHF\" instructions which are  supported  by  AMD64.\nThese are load and store instructions, respectively, for certain status flags.  In 64-bit\nmode, the \"SAHF\" instruction is used to optimize \"fmod\", \"drem\", and \"remainder\" built-in\nfunctions; see Other Builtins for details.\n"
                },
                {
                    "name": "-mmovbe",
                    "content": "This  option  enables use of the \"movbe\" instruction to implement \"builtinbswap32\" and\n\"builtinbswap64\".\n"
                },
                {
                    "name": "-mshstk",
                    "content": "The -mshstk  option  enables  shadow  stack  built-in  functions  from  x86  Control-flow\nEnforcement Technology (CET).\n"
                },
                {
                    "name": "-mcrc32",
                    "content": "This      option      enables      built-in      functions      \"builtinia32crc32qi\",\n\"builtinia32crc32hi\",  \"builtinia32crc32si\"   and   \"builtinia32crc32di\"   to\ngenerate the \"crc32\" machine instruction.\n"
                },
                {
                    "name": "-mmwait",
                    "content": "This     option     enables     built-in    functions    \"builtinia32monitor\",    and\n\"builtinia32mwait\" to generate the \"monitor\" and \"mwait\" machine instructions.\n"
                },
                {
                    "name": "-mrecip",
                    "content": "This option enables use of \"RCPSS\"  and  \"RSQRTSS\"  instructions  (and  their  vectorized\nvariants  \"RCPPS\"  and  \"RSQRTPS\")  with  an  additional  Newton-Raphson step to increase\nprecision instead of \"DIVSS\" and \"SQRTSS\" (and their  vectorized  variants)  for  single-\nprecision   floating-point   arguments.   These  instructions  are  generated  only  when\n-funsafe-math-optimizations   is   enabled   together   with    -ffinite-math-only    and\n-fno-trapping-math.   Note  that  while the throughput of the sequence is higher than the\nthroughput of the non-reciprocal instruction,  the  precision  of  the  sequence  can  be\ndecreased by up to 2 ulp (i.e. the inverse of 1.0 equals 0.99999994).\n\nNote  that  GCC  implements  \"1.0f/sqrtf(x)\" in terms of \"RSQRTSS\" (or \"RSQRTPS\") already\nwith -ffast-math (or the above option combination), and doesn't need -mrecip.\n\nAlso note that GCC emits the above  sequence  with  additional  Newton-Raphson  step  for\nvectorized single-float division and vectorized sqrtf(x) already with -ffast-math (or the\nabove option combination), and doesn't need -mrecip.\n"
                },
                {
                    "name": "-mrecip=_",
                    "content": "This option controls which reciprocal estimate instructions may be used.  opt is a comma-\nseparated list of options, which may be preceded by a ! to invert the option:\n\nall Enable all estimate instructions.\n\ndefault\nEnable the default instructions, equivalent to -mrecip.\n\nnone\nDisable all estimate instructions, equivalent to -mno-recip.\n\ndiv Enable the approximation for scalar division.\n\nvec-div\nEnable the approximation for vectorized division.\n\nsqrt\nEnable the approximation for scalar square root.\n\nvec-sqrt\nEnable the approximation for vectorized square root.\n\nSo,  for  example, -mrecip=all,!sqrt enables all of the reciprocal approximations, except\nfor square root.\n"
                },
                {
                    "name": "-mveclibabi=_",
                    "content": "Specifies the ABI type to use for  vectorizing  intrinsics  using  an  external  library.\nSupported  values  for type are svml for the Intel short vector math library and acml for\nthe  AMD  math  core  library.   To  use   this   option,   both   -ftree-vectorize   and\n-funsafe-math-optimizations  have  to  be  enabled,  and  an  SVML or ACML ABI-compatible\nlibrary must be specified at link time.\n\nGCC  currently  emits  calls  to   \"vmldExp2\",   \"vmldLn2\",   \"vmldLog102\",   \"vmldPow2\",\n\"vmldTanh2\", \"vmldTan2\", \"vmldAtan2\", \"vmldAtanh2\", \"vmldCbrt2\", \"vmldSinh2\", \"vmldSin2\",\n\"vmldAsinh2\",    \"vmldAsin2\",   \"vmldCosh2\",   \"vmldCos2\",   \"vmldAcosh2\",   \"vmldAcos2\",\n\"vmlsExp4\", \"vmlsLn4\", \"vmlsLog104\", \"vmlsPow4\",  \"vmlsTanh4\",  \"vmlsTan4\",  \"vmlsAtan4\",\n\"vmlsAtanh4\",    \"vmlsCbrt4\",   \"vmlsSinh4\",   \"vmlsSin4\",   \"vmlsAsinh4\",   \"vmlsAsin4\",\n\"vmlsCosh4\", \"vmlsCos4\", \"vmlsAcosh4\" and \"vmlsAcos4\"  for  corresponding  function  type\nwhen   -mveclibabi=svml   is   used,   and   \"vrd2sin\",   \"vrd2cos\",  \"vrd2exp\",\n\"vrd2log\", \"vrd2log2\", \"vrd2log10\", \"vrs4sinf\", \"vrs4cosf\", \"vrs4expf\",\n\"vrs4logf\", \"vrs4log2f\", \"vrs4log10f\" and \"vrs4powf\"  for  the  corresponding\nfunction type when -mveclibabi=acml is used.\n"
                },
                {
                    "name": "-mabi=_",
                    "content": "Generate  code for the specified calling convention.  Permissible values are sysv for the\nABI used on GNU/Linux and other systems, and ms for the Microsoft ABI.  The default is to\nuse the Microsoft ABI when targeting Microsoft Windows and the  SysV  ABI  on  all  other\nsystems.   You  can  control  this  behavior for specific functions by using the function\nattributes \"msabi\" and \"sysvabi\".\n"
                },
                {
                    "name": "-mforce-indirect-call",
                    "content": "Force all calls to functions to be indirect. This is useful when  using  Intel  Processor\nTrace where it generates more precise timing information for function calls.\n"
                },
                {
                    "name": "-mmanual-endbr",
                    "content": "Insert  ENDBR  instruction  at function entry only via the \"cfcheck\" function attribute.\nThis is useful  when  used  with  the  option  -fcf-protection=branch  to  control  ENDBR\ninsertion at the function entry.\n"
                },
                {
                    "name": "-mcet-switch",
                    "content": "By  default, CET instrumentation is turned off on switch statements that use a jump table\nand indirect branch track is disabled.  Since jump tables are stored in read-only memory,\nthis does not result in a direct loss of hardening.  But  if  the  jump  table  index  is\nattacker-controlled,  the indirect jump may not be constrained by CET.  This option turns\non CET instrumentation to enable indirect branch track for switch  statements  with  jump\ntables which leads to the jump targets reachable via any indirect jumps.\n"
                },
                {
                    "name": "-mcall-ms2sysv-xlogues",
                    "content": "Due  to  differences in 64-bit ABIs, any Microsoft ABI function that calls a System V ABI\nfunction must consider RSI, RDI and XMM6-15 as  clobbered.   By  default,  the  code  for\nsaving  and  restoring  these  registers  is  emitted inline, resulting in fairly lengthy\nprologues and epilogues.  Using -mcall-ms2sysv-xlogues emits prologues and epilogues that\nuse stubs in the static portion of libgcc to  perform  these  saves  and  restores,  thus\nreducing function size at the cost of a few extra instructions.\n"
                },
                {
                    "name": "-mtls-dialect=_",
                    "content": "Generate  code  to access thread-local storage using the gnu or gnu2 conventions.  gnu is\nthe conservative default; gnu2 is more efficient, but it may add  compile-  and  run-time\nrequirements that cannot be satisfied on all systems.\n"
                },
                {
                    "name": "-mpush-args",
                    "content": ""
                },
                {
                    "name": "-mno-push-args",
                    "content": "Use  PUSH  operations  to  store outgoing parameters.  This method is shorter and usually\nequally fast as method using SUB/MOV operations and is enabled by default.  In some cases\ndisabling  it  may  improve  performance  because  of  improved  scheduling  and  reduced\ndependencies.\n"
                },
                {
                    "name": "-maccumulate-outgoing-args",
                    "content": "If  enabled,  the  maximum amount of space required for outgoing arguments is computed in\nthe  function  prologue.   This  is  faster  on  most  modern  CPUs  because  of  reduced\ndependencies,  improved  scheduling  and  reduced  stack  usage  when the preferred stack\nboundary is not equal to 2.  The drawback is a  notable  increase  in  code  size.   This\nswitch implies -mno-push-args.\n"
                },
                {
                    "name": "-mthreads",
                    "content": "Support  thread-safe  exception  handling  on  MinGW.   Programs that rely on thread-safe\nexception handling must compile and link  all  code  with  the  -mthreads  option.   When\ncompiling,  -mthreads  defines  -DMT;  when linking, it links in a special thread helper\nlibrary -lmingwthrd which cleans up per-thread exception-handling data.\n"
                },
                {
                    "name": "-mms-bitfields",
                    "content": ""
                },
                {
                    "name": "-mno-ms-bitfields",
                    "content": "Enable/disable bit-field layout compatible with the native Microsoft Windows compiler.\n\nIf \"packed\" is used on a structure, or if  bit-fields  are  used,  it  may  be  that  the\nMicrosoft  ABI  lays  out  the  structure  differently  than  the  way GCC normally does.\nParticularly when moving packed data between functions compiled with GCC and  the  native\nMicrosoft  compiler  (either via function call or as data in a file), it may be necessary\nto access either format.\n\nThis option is enabled by default for Microsoft Windows targets.  This behavior can  also\nbe  controlled  locally by use of variable or type attributes.  For more information, see\nx86 Variable Attributes and x86 Type Attributes.\n\nThe Microsoft structure layout algorithm is fairly simple with the exception of the  bit-\nfield  packing.   The  padding  and alignment of members of structures and whether a bit-\nfield can straddle a storage-unit boundary are determine by these rules:\n\n1. Structure members are stored sequentially in the order in which they are\ndeclared: the first member has the lowest memory address  and  the  last  member  the\nhighest.\n\n2. Every data object has an alignment requirement.  The alignment requirement\nfor  all  data except structures, unions, and arrays is either the size of the object\nor the current packing size (specified with either the  \"aligned\"  attribute  or  the\n\"pack\" pragma), whichever is less.  For structures, unions, and arrays, the alignment\nrequirement  is  the  largest  alignment requirement of its members.  Every object is\nallocated an offset so that:\n\noffset % alignmentrequirement == 0\n\n3. Adjacent bit-fields are packed into the same 1-, 2-, or 4-byte allocation\nunit if the integral types are the same size and if the next bit-field fits into  the\ncurrent allocation unit without crossing the boundary imposed by the common alignment\nrequirements of the bit-fields.\n\nMSVC interprets zero-length bit-fields in the following ways:\n\n1. If a zero-length bit-field is inserted between two bit-fields that\nare normally coalesced, the bit-fields are not coalesced.\n\nFor example:\n\nstruct\n{\nunsigned long bf1 : 12;\nunsigned long : 0;\nunsigned long bf2 : 12;\n} t1;\n\nThe  size of \"t1\" is 8 bytes with the zero-length bit-field.  If the zero-length bit-\nfield were removed, \"t1\"'s size would be 4 bytes.\n\n2. If a zero-length bit-field is inserted after a bit-field, \"foo\", and the\nalignment of the zero-length bit-field is greater than the member  that  follows  it,\n\"bar\", \"bar\" is aligned as the type of the zero-length bit-field.\n\nFor example:\n\nstruct\n{\nchar foo : 4;\nshort : 0;\nchar bar;\n} t2;\n\nstruct\n{\nchar foo : 4;\nshort : 0;\ndouble bar;\n} t3;\n\nFor  \"t2\",  \"bar\" is placed at offset 2, rather than offset 1.  Accordingly, the size\nof \"t2\" is 4.  For \"t3\", the zero-length bit-field does not affect the  alignment  of\n\"bar\" or, as a result, the size of the structure.\n\nTaking this into account, it is important to note the following:\n\n1. If a zero-length bit-field follows a normal bit-field, the type of the\nzero-length  bit-field  may  affect  the alignment of the structure as whole. For\nexample, \"t2\" has a size of 4 bytes, since the zero-length  bit-field  follows  a\nnormal bit-field, and is of type short.\n\n2. Even if a zero-length bit-field is not followed by a normal bit-field, it may\nstill affect the alignment of the structure:\n\nstruct\n{\nchar foo : 6;\nlong : 0;\n} t4;\n\nHere, \"t4\" takes up 4 bytes.\n\n3. Zero-length bit-fields following non-bit-field members are ignored:\nstruct\n{\nchar foo;\nlong : 0;\nchar bar;\n} t5;\n\nHere, \"t5\" takes up 2 bytes.\n"
                },
                {
                    "name": "-mno-align-stringops",
                    "content": "Do not align the destination of inlined string operations.  This switch reduces code size\nand improves performance in case the destination is already aligned, but GCC doesn't know\nabout it.\n"
                },
                {
                    "name": "-minline-all-stringops",
                    "content": "By default GCC inlines string operations only when the destination is known to be aligned\nto  least a 4-byte boundary.  This enables more inlining and increases code size, but may\nimprove performance of code that depends on fast \"memcpy\" and \"memset\" for short lengths.\nThe option enables inline expansion of \"strlen\" for all pointer alignments.\n"
                },
                {
                    "name": "-minline-stringops-dynamically",
                    "content": "For string operations of unknown size, use run-time checks with  inline  code  for  small\nblocks and a library call for large blocks.\n"
                },
                {
                    "name": "-mstringop-strategy=_",
                    "content": "Override the internal decision heuristic for the particular algorithm to use for inlining\nstring operations.  The allowed values for alg are:\n\nrepbyte\nrep4byte\nrep8byte\nExpand using i386 \"rep\" prefix of the specified size.\n\nbyteloop\nloop\nunrolledloop\nExpand into an inline loop.\n\nlibcall\nAlways use a library call.\n"
                },
                {
                    "name": "-mmemcpy-strategy=_",
                    "content": "Override  the  internal  decision  heuristic  to  decide  if \"builtinmemcpy\" should be\ninlined and what inline algorithm to use when the expected size of the copy operation  is\nknown.  strategy  is  a comma-separated list of alg:maxsize:destalign triplets.  alg is\nspecified in -mstringop-strategy, maxsize specifies the max byte size with which  inline\nalgorithm alg is allowed.  For the last triplet, the maxsize must be -1. The maxsize of\nthe  triplets  in  the list must be specified in increasing order.  The minimal byte size\nfor alg is 0 for the first triplet and \"maxsize + 1\" of the preceding range.\n"
                },
                {
                    "name": "-mmemset-strategy=_",
                    "content": "The  option  is  similar  to  -mmemcpy-strategy=   except   that   it   is   to   control\n\"builtinmemset\" expansion.\n"
                },
                {
                    "name": "-momit-leaf-frame-pointer",
                    "content": "Don't  keep  the  frame  pointer  in  a  register  for  leaf  functions.  This avoids the\ninstructions to save, set up, and restore frame pointers  and  makes  an  extra  register\navailable  in  leaf  functions.   The  option -fomit-leaf-frame-pointer removes the frame\npointer for leaf functions, which might make debugging harder.\n"
                },
                {
                    "name": "-mtls-direct-seg-refs",
                    "content": ""
                },
                {
                    "name": "-mno-tls-direct-seg-refs",
                    "content": "Controls whether TLS variables may be accessed with offsets from the TLS segment register\n(%gs for 32-bit, %fs for 64-bit), or whether the  thread  base  pointer  must  be  added.\nWhether  or  not  this  is valid depends on the operating system, and whether it maps the\nsegment to cover the entire TLS area.\n\nFor systems that use the GNU C Library, the default is on.\n"
                },
                {
                    "name": "-msse2avx",
                    "content": ""
                },
                {
                    "name": "-mno-sse2avx",
                    "content": "Specify that the assembler should encode SSE instructions with VEX  prefix.   The  option\n-mavx turns this on by default.\n"
                },
                {
                    "name": "-mfentry",
                    "content": ""
                },
                {
                    "name": "-mno-fentry",
                    "content": "If  profiling is active (-pg), put the profiling counter call before the prologue.  Note:\nOn x86 architectures the attribute \"mshookprologue\" isn't possible at  the  moment  for\n-mfentry and -pg.\n"
                },
                {
                    "name": "-mrecord-mcount",
                    "content": ""
                },
                {
                    "name": "-mno-record-mcount",
                    "content": "If  profiling  is active (-pg), generate a mcountloc section that contains pointers to\neach profiling call. This is useful for automatically patching and out calls.\n"
                },
                {
                    "name": "-mnop-mcount",
                    "content": ""
                },
                {
                    "name": "-mno-nop-mcount",
                    "content": "If profiling is active (-pg), generate the calls to the profiling functions as NOPs. This\nis useful when they should be patched in later dynamically. This is  likely  only  useful\ntogether with -mrecord-mcount.\n"
                },
                {
                    "name": "-minstrument-return=_",
                    "content": "Instrument  function  exit  in -pg -mfentry instrumented functions with call to specified\nfunction. This only instruments true returns ending  with  ret,  but  not  sibling  calls\nending  with  jump.  Valid  types  are none to not instrument, call to generate a call to\nreturn, or nop5 to generate a 5 byte nop.\n"
                },
                {
                    "name": "-mrecord-return",
                    "content": ""
                },
                {
                    "name": "-mno-record-return",
                    "content": "Generate a returnloc section pointing to all return instrumentation code.\n"
                },
                {
                    "name": "-mfentry-name=_",
                    "content": "Set name of fentry symbol called at function entry for -pg -mfentry functions.\n"
                },
                {
                    "name": "-mfentry-section=_",
                    "content": "Set name of section to record -mrecord-mcount calls (default mcountloc).\n"
                },
                {
                    "name": "-mskip-rax-setup",
                    "content": ""
                },
                {
                    "name": "-mno-skip-rax-setup",
                    "content": "When  generating  code  for  the  x86-64  architecture  with  SSE  extensions   disabled,\n-mskip-rax-setup  can  be used to skip setting up RAX register when there are no variable\narguments passed in vector registers.\n\nWarning: Since RAX register is used to avoid unnecessarily  saving  vector  registers  on\nstack  when  passing variable arguments, the impacts of this option are callees may waste\nsome stack space, misbehave or jump to a random location.  GCC 4.4 or  newer  don't  have\nthose issues, regardless the RAX register value.\n"
                },
                {
                    "name": "-m8bit-idiv",
                    "content": ""
                },
                {
                    "name": "-mno-8bit-idiv",
                    "content": "On  some  processors,  like Intel Atom, 8-bit unsigned integer divide is much faster than\n32-bit/64-bit integer divide.  This option generates a run-time check.  If both  dividend\nand  divisor  are within range of 0 to 255, 8-bit unsigned integer divide is used instead\nof 32-bit/64-bit integer divide.\n"
                },
                {
                    "name": "-mavx256-split-unaligned-load",
                    "content": ""
                },
                {
                    "name": "-mavx256-split-unaligned-store",
                    "content": "Split 32-byte AVX unaligned load and store.\n"
                },
                {
                    "name": "-mstack-protector-guard=_",
                    "content": ""
                },
                {
                    "name": "-mstack-protector-guard-reg=_",
                    "content": ""
                },
                {
                    "name": "-mstack-protector-guard-offset=_",
                    "content": "Generate stack protection code using canary at guard.  Supported locations are global for\nglobal canary or tls for per-thread canary in the TLS block (the default).   This  option\nhas effect only when -fstack-protector or -fstack-protector-all is specified.\n\nWith    the    latter    choice    the    options   -mstack-protector-guard-reg=reg   and\n-mstack-protector-guard-offset=offset furthermore specify which segment register (%fs  or\n%gs)  to use as base register for reading the canary, and from what offset from that base\nregister.  The default for those is as specified in the relevant ABI.\n"
                },
                {
                    "name": "-mgeneral-regs-only",
                    "content": "Generate code that uses only the general-purpose registers.  This prevents  the  compiler\nfrom using floating-point, vector, mask and bound registers.\n"
                },
                {
                    "name": "-mrelax-cmpxchg-loop",
                    "content": "When emitting a compare-and-swap loop for sync Builtins and atomic Builtins lacking a\nnative  instruction,  optimize  for  the  highly contended case by issuing an atomic load\nbefore the \"CMPXCHG\" instruction, and using the \"PAUSE\" instruction  to  save  CPU  power\nwhen restarting the loop.\n"
                },
                {
                    "name": "-mindirect-branch=_",
                    "content": "Convert  indirect  call  and jump with choice.  The default is keep, which keeps indirect\ncall and jump unmodified.  thunk converts indirect call  and  jump  to  call  and  return\nthunk.   thunk-inline  converts  indirect call and jump to inlined call and return thunk.\nthunk-extern converts indirect call and jump to external call and return  thunk  provided\nin  a  separate  object  file.   You can control this behavior for a specific function by\nusing the function attribute \"indirectbranch\".\n\nNote   that   -mcmodel=large   is   incompatible   with    -mindirect-branch=thunk    and\n-mindirect-branch=thunk-extern since the thunk function may not be reachable in the large\ncode model.\n\nNote  that -mindirect-branch=thunk-extern is compatible with -fcf-protection=branch since\nthe external thunk can be made to enable control-flow check.\n"
                },
                {
                    "name": "-mfunction-return=_",
                    "content": "Convert function return with choice.  The default is keep, which  keeps  function  return\nunmodified.   thunk  converts  function  return  to  call and return thunk.  thunk-inline\nconverts function return  to  inlined  call  and  return  thunk.   thunk-extern  converts\nfunction  return  to  external  call and return thunk provided in a separate object file.\nYou can control this behavior for a specific function by  using  the  function  attribute\n\"functionreturn\".\n\nNote  that -mindirect-return=thunk-extern is compatible with -fcf-protection=branch since\nthe external thunk can be made to enable control-flow check.\n\nNote   that   -mcmodel=large   is   incompatible   with    -mfunction-return=thunk    and\n-mfunction-return=thunk-extern since the thunk function may not be reachable in the large\ncode model.\n"
                },
                {
                    "name": "-mindirect-branch-register",
                    "content": "Force indirect call and jump via register.\n"
                },
                {
                    "name": "-mharden-sls=_",
                    "content": "Generate  code  to  mitigate  against  straight  line speculation (SLS) with choice.  The\ndefault is none which disables all SLS  hardening.   return  enables  SLS  hardening  for\nfunction  returns.   indirect-jmp  enables SLS hardening for indirect jumps.  all enables\nall SLS hardening.\n"
                },
                {
                    "name": "-mindirect-branch-cs-prefix",
                    "content": "Add CS prefix to call and jmp to indirect thunk with branch target in r8-r15 registers so\nthat the call and jmp instruction length is 6 bytes to allow them  to  be  replaced  with\nlfence; call *%r8-r15 or lfence; jmp *%r8-r15 at run-time.\n\nThese  -m  switches  are  supported  in  addition to the above on x86-64 processors in 64-bit\nenvironments.\n"
                },
                {
                    "name": "-m32",
                    "content": ""
                },
                {
                    "name": "-m64",
                    "content": ""
                },
                {
                    "name": "-mx32",
                    "content": ""
                },
                {
                    "name": "-m16",
                    "content": ""
                },
                {
                    "name": "-miamcu",
                    "content": "Generate code for a 16-bit, 32-bit or 64-bit environment.  The -m32  option  sets  \"int\",\n\"long\", and pointer types to 32 bits, and generates code that runs in 32-bit mode.\n\nThe  -m64  option  sets  \"int\"  to  32  bits and \"long\" and pointer types to 64 bits, and\ngenerates code for the x86-64 architecture.  For Darwin only the -m64 option  also  turns\noff the -fno-pic and -mdynamic-no-pic options.\n\nThe -mx32 option sets \"int\", \"long\", and pointer types to 32 bits, and generates code for\nthe x86-64 architecture.\n\nThe -m16 option is the same as -m32, except for that it outputs the \".code16gcc\" assembly\ndirective  at  the  beginning of the assembly output so that the binary can run in 16-bit\nmode.\n\nThe -miamcu option generates code which conforms to Intel MCU  psABI.   It  requires  the\n-m32 option to be turned on.\n"
                },
                {
                    "name": "-mno-red-zone",
                    "content": "Do  not  use  a  so-called  \"red  zone\" for x86-64 code.  The red zone is mandated by the\nx86-64 ABI; it is a 128-byte area beyond the location of the stack pointer  that  is  not\nmodified  by  signal  or  interrupt handlers and therefore can be used for temporary data\nwithout adjusting the stack pointer.  The flag -mno-red-zone disables this red zone.\n"
                },
                {
                    "name": "-mcmodel=small",
                    "content": "Generate code for the small code model: the program and its symbols must be linked in the\nlower 2 GB of the address space.  Pointers are 64 bits.  Programs can  be  statically  or\ndynamically linked.  This is the default code model.\n"
                },
                {
                    "name": "-mcmodel=kernel",
                    "content": "Generate  code  for  the  kernel code model.  The kernel runs in the negative 2 GB of the\naddress space.  This model has to be used for Linux kernel code.\n"
                },
                {
                    "name": "-mcmodel=medium",
                    "content": "Generate code for the medium model: the program is linked  in  the  lower  2  GB  of  the\naddress  space.   Small  symbols  are  also placed there.  Symbols with sizes larger than\n-mlarge-data-threshold are put into large data or BSS sections and can be  located  above\n2GB.  Programs can be statically or dynamically linked.\n"
                },
                {
                    "name": "-mcmodel=large",
                    "content": "Generate  code  for the large model.  This model makes no assumptions about addresses and\nsizes of sections.\n"
                },
                {
                    "name": "-maddress-mode=long",
                    "content": "Generate code for long  address  mode.   This  is  only  supported  for  64-bit  and  x32\nenvironments.  It is the default address mode for 64-bit environments.\n"
                },
                {
                    "name": "-maddress-mode=short",
                    "content": "Generate  code  for  short  address  mode.   This  is  only  supported for 32-bit and x32\nenvironments.  It is the default address mode for 32-bit and x32 environments.\n"
                },
                {
                    "name": "-mneeded",
                    "content": ""
                },
                {
                    "name": "-mno-needed",
                    "content": "Emit GNUPROPERTYX86ISA1NEEDED GNU property for Linux target to indicate  the  micro-\narchitecture ISA level required to execute the binary.\n"
                },
                {
                    "name": "-mno-direct-extern-access",
                    "content": "Without  -fpic  nor  -fPIC,  always use the GOT pointer to access external symbols.  With\n-fpic or -fPIC, treat access to protected symbols  as  local  symbols.   The  default  is\n-mdirect-extern-access.\n\nWarning: shared libraries compiled with -mno-direct-extern-access and executable compiled\nwith -mdirect-extern-access may not be binary compatible if protected symbols are used in\nshared libraries and executable.\n"
                },
                {
                    "name": "-munroll-only-small-loops",
                    "content": "Controls conservative small loop unrolling. It is default enabled by O2, and unrolls loop\nwith  less  than 4 insns by 1 time. Explicit -f[no-]unroll-[all-]loops would disable this\nflag to avoid any unintended unrolling behavior that user does not want.\n"
                },
                {
                    "name": "-mlam=_",
                    "content": "LAM(linear-address masking) allows special bits in the pointer to be used  for  metadata.\nThe  default is none. With u48, pointer bits in positions 62:48 can be used for metadata;\nWith u57, pointer bits in positions 62:57 can be used for metadata.\n\nx86 Windows Options\n\nThese additional options are available for Microsoft Windows targets:\n"
                },
                {
                    "name": "-mconsole",
                    "content": "This option specifies that a console application is to be generated, by  instructing  the\nlinker  to  set  the  PE  header  subsystem type required for console applications.  This\noption is available for Cygwin and MinGW targets and  is  enabled  by  default  on  those\ntargets.\n"
                },
                {
                    "name": "-mdll",
                    "content": "This  option  is  available  for  Cygwin  and MinGW targets.  It specifies that a DLL---a\ndynamic link library---is to be generated, enabling the selection of the required runtime\nstartup object and entry point.\n"
                },
                {
                    "name": "-mnop-fun-dllimport",
                    "content": "This option is available for Cygwin and MinGW targets.  It specifies that the \"dllimport\"\nattribute should be ignored.\n"
                },
                {
                    "name": "-mthreads",
                    "content": "This option is available for MinGW  targets.  It  specifies  that  MinGW-specific  thread\nsupport is to be used.\n"
                },
                {
                    "name": "-municode",
                    "content": "This  option  is  available  for MinGW-w64 targets.  It causes the \"UNICODE\" preprocessor\nmacro to be predefined, and chooses Unicode-capable runtime startup code.\n"
                },
                {
                    "name": "-mwin32",
                    "content": "This option is available for Cygwin and MinGW targets.  It  specifies  that  the  typical\nMicrosoft  Windows  predefined  macros  are  to be set in the pre-processor, but does not\ninfluence the choice of runtime library/startup code.\n"
                },
                {
                    "name": "-mwindows",
                    "content": "This option is available  for  Cygwin  and  MinGW  targets.   It  specifies  that  a  GUI\napplication  is  to be generated by instructing the linker to set the PE header subsystem\ntype appropriately.\n"
                },
                {
                    "name": "-fno-set-stack-executable",
                    "content": "This option is available for MinGW targets. It specifies that the executable flag for the\nstack used by nested functions isn't set. This  is  necessary  for  binaries  running  in\nkernel  mode  of  Microsoft  Windows,  as  there  the  User32  API,  which is used to set\nexecutable privileges, isn't available.\n"
                },
                {
                    "name": "-fwritable-relocated-rdata",
                    "content": "This option is available for MinGW and Cygwin targets.  It specifies that  relocated-data\nin  read-only  section  is  put  into the \".data\" section.  This is a necessary for older\nruntimes not supporting modification of \".rdata\" sections for pseudo-relocation.\n"
                },
                {
                    "name": "-mpe-aligned-commons",
                    "content": "This option is available for Cygwin  and  MinGW  targets.   It  specifies  that  the  GNU\nextension  to  the  PE file format that permits the correct alignment of COMMON variables\nshould be used when generating code.  It is enabled by default if GCC  detects  that  the\ntarget assembler found during configuration supports the feature.\n\nSee also under x86 Options for standard options.\n\nXstormy16 Options\n\nThese options are defined for Xstormy16:\n"
                },
                {
                    "name": "-msim",
                    "content": "Choose startup files and linker script suitable for the simulator.\n\nXtensa Options\n\nThese options are supported for Xtensa targets:\n"
                },
                {
                    "name": "-mconst16",
                    "content": ""
                },
                {
                    "name": "-mno-const16",
                    "content": "Enable  or  disable  use  of  \"CONST16\"  instructions  for  loading constant values.  The\n\"CONST16\" instruction is currently not a standard option from Tensilica.   When  enabled,\n\"CONST16\" instructions are always used in place of the standard \"L32R\" instructions.  The\nuse of \"CONST16\" is enabled by default only if the \"L32R\" instruction is not available.\n"
                },
                {
                    "name": "-mfused-madd",
                    "content": ""
                },
                {
                    "name": "-mno-fused-madd",
                    "content": "Enable  or  disable  use  of fused multiply/add and multiply/subtract instructions in the\nfloating-point option.  This has no effect if  the  floating-point  option  is  not  also\nenabled.   Disabling  fused  multiply/add  and  multiply/subtract instructions forces the\ncompiler to use separate instructions for the multiply and add/subtract operations.  This\nmay be desirable in some cases where strict IEEE 754-compliant results are required:  the\nfused  multiply  add/subtract  instructions do not round the intermediate result, thereby\nproducing results with more bits of  precision  than  specified  by  the  IEEE  standard.\nDisabling  fused  multiply add/subtract instructions also ensures that the program output\nis not  sensitive  to  the  compiler's  ability  to  combine  multiply  and  add/subtract\noperations.\n"
                },
                {
                    "name": "-mserialize-volatile",
                    "content": ""
                },
                {
                    "name": "-mno-serialize-volatile",
                    "content": "When  this  option  is  enabled, GCC inserts \"MEMW\" instructions before \"volatile\" memory\nreferences to guarantee sequential consistency.   The  default  is  -mserialize-volatile.\nUse -mno-serialize-volatile to omit the \"MEMW\" instructions.\n"
                },
                {
                    "name": "-mforce-no-pic",
                    "content": "For targets, like GNU/Linux, where all user-mode Xtensa code must be position-independent\ncode (PIC), this option disables PIC for compiling kernel code.\n"
                },
                {
                    "name": "-mtext-section-literals",
                    "content": ""
                },
                {
                    "name": "-mno-text-section-literals",
                    "content": "These   options   control   the   treatment   of   literal   pools.    The   default   is\n-mno-text-section-literals, which places literals in a separate  section  in  the  output\nfile.   This  allows  the literal pool to be placed in a data RAM/ROM, and it also allows\nthe linker to combine literal pools  from  separate  object  files  to  remove  redundant\nliterals   and  improve  code  size.   With  -mtext-section-literals,  the  literals  are\ninterspersed in the text section in order to keep them as  close  as  possible  to  their\nreferences.   This may be necessary for large assembly files.  Literals for each function\nare placed right before that function.\n"
                },
                {
                    "name": "-mauto-litpools",
                    "content": ""
                },
                {
                    "name": "-mno-auto-litpools",
                    "content": "These options control the treatment of literal pools.  The default is -mno-auto-litpools,\nwhich  places  literals   in   a   separate   section   in   the   output   file   unless\n-mtext-section-literals  is  used.  With -mauto-litpools the literals are interspersed in\nthe text section by  the  assembler.   Compiler  does  not  produce  explicit  \".literal\"\ndirectives  and  loads literals into registers with \"MOVI\" instructions instead of \"L32R\"\nto let the assembler do relaxation and place literals as necessary.  This  option  allows\nassembler  to  create several literal pools per function and assemble very big functions,\nwhich may not be possible with -mtext-section-literals.\n"
                },
                {
                    "name": "-mtarget-align",
                    "content": ""
                },
                {
                    "name": "-mno-target-align",
                    "content": "When this  option  is  enabled,  GCC  instructs  the  assembler  to  automatically  align\ninstructions  to  reduce  branch  penalties  at  the  expense  of some code density.  The\nassembler attempts to  widen  density  instructions  to  align  branch  targets  and  the\ninstructions following call instructions.  If there are not enough preceding safe density\ninstructions to align a target, no widening is performed.  The default is -mtarget-align.\nThese options do not affect the treatment of auto-aligned instructions like \"LOOP\", which\nthe  assembler always aligns, either by widening density instructions or by inserting NOP\ninstructions.\n"
                },
                {
                    "name": "-mlongcalls",
                    "content": ""
                },
                {
                    "name": "-mno-longcalls",
                    "content": "When this option is enabled, GCC instructs the assembler to  translate  direct  calls  to\nindirect  calls  unless it can determine that the target of a direct call is in the range\nallowed by the  call  instruction.   This  translation  typically  occurs  for  calls  to\nfunctions  in other source files.  Specifically, the assembler translates a direct \"CALL\"\ninstruction  into  an  \"L32R\"  followed  by  a  \"CALLX\"  instruction.   The  default   is\n-mno-longcalls.   This  option  should  be  used  in  programs  where the call target can\npotentially be out of range.  This option  is  implemented  in  the  assembler,  not  the\ncompiler,   so   the   assembly   code   generated   by   GCC  still  shows  direct  call\ninstructions---look at the disassembled object code to see the actual instructions.  Note\nthat the assembler uses an indirect call for every cross-file call, not just  those  that\nreally are out of range.\n"
                },
                {
                    "name": "-mabi=_",
                    "content": "Generate  code  for the specified ABI.  Permissible values are: call0, windowed.  Default\nABI is chosen by the Xtensa core configuration.\n"
                },
                {
                    "name": "-mabi=call0",
                    "content": "When this option is enabled function parameters are  passed  in  registers  \"a2\"  through\n\"a7\", registers \"a12\" through \"a15\" are caller-saved, and register \"a15\" may be used as a\nframe  pointer.   When  this  version  of  the  ABI  is enabled the C preprocessor symbol\n\"XTENSACALL0ABI\" is defined.\n"
                },
                {
                    "name": "-mabi=windowed",
                    "content": "When this option is enabled function parameters are passed  in  registers  \"a10\"  through\n\"a15\",  and  called  function rotates register window by 8 registers on entry so that its\narguments are found in registers \"a2\" through \"a7\".  Register \"a7\" may be used as a frame\npointer.  Register window is rotated 8 registers back upon return.  When this version  of\nthe ABI is enabled the C preprocessor symbol \"XTENSAWINDOWEDABI\" is defined.\n"
                },
                {
                    "name": "-mextra-l32r-costs=_",
                    "content": "Specify  an  extra  cost  of instruction RAM/ROM access for \"L32R\" instructions, in clock\ncycles.  This affects, when optimizing for speed, whether loading a constant from literal\npool using \"L32R\" or synthesizing the  constant  from  a  small  one  with  a  couple  of\narithmetic instructions.  The default value is 0.\n\nzSeries Options\n\nThese are listed under\n"
                }
            ]
        },
        "ENVIRONMENT": {
            "content": "This  section  describes several environment variables that affect how GCC operates.  Some of\nthem work by specifying directories or prefixes to use when searching for  various  kinds  of\nfiles.  Some are used to specify other aspects of the compilation environment.\n\nNote  that  you can also specify places to search using options such as -B, -I and -L.  These\ntake precedence over places  specified  using  environment  variables,  which  in  turn  take\nprecedence over those specified by the configuration of GCC.\n\nLANG\nLCCTYPE\nLCMESSAGES\nLCALL\nThese  environment variables control the way that GCC uses localization information which\nallows GCC to  work  with  different  national  conventions.   GCC  inspects  the  locale\ncategories  LCCTYPE  and  LCMESSAGES  if it has been configured to do so.  These locale\ncategories can be set to any value supported by your installation.  A  typical  value  is\nenGB.UTF-8 for English in the United Kingdom encoded in UTF-8.\n\nThe  LCCTYPE  environment  variable  specifies character classification.  GCC uses it to\ndetermine the character boundaries in  a  string;  this  is  needed  for  some  multibyte\nencodings  that  contain  quote and escape characters that are otherwise interpreted as a\nstring end or escape.\n\nThe LCMESSAGES  environment  variable  specifies  the  language  to  use  in  diagnostic\nmessages.\n\nIf  the  LCALL  environment  variable  is  set,  it  overrides the value of LCCTYPE and\nLCMESSAGES; otherwise, LCCTYPE and  LCMESSAGES  default  to  the  value  of  the  LANG\nenvironment  variable.  If none of these variables are set, GCC defaults to traditional C\nEnglish behavior.\n\nTMPDIR\nIf TMPDIR is set, it specifies the directory  to  use  for  temporary  files.   GCC  uses\ntemporary  files  to  hold  the output of one stage of compilation which is to be used as\ninput to the next stage: for example, the output of the preprocessor, which is the  input\nto the compiler proper.\n\nGCCCOMPAREDEBUG\nSetting GCCCOMPAREDEBUG is nearly equivalent to passing -fcompare-debug to the compiler\ndriver.  See the documentation of this option for more details.\n\nGCCEXECPREFIX\nIf  GCCEXECPREFIX  is set, it specifies a prefix to use in the names of the subprograms\nexecuted by the compiler.  No slash is added when this prefix is combined with  the  name\nof a subprogram, but you can specify a prefix that ends with a slash if you wish.\n\nIf  GCCEXECPREFIX  is  not set, GCC attempts to figure out an appropriate prefix to use\nbased on the pathname it is invoked with.\n\nIf GCC cannot find the subprogram using the specified prefix, it  tries  looking  in  the\nusual places for the subprogram.\n\nThe default value of GCCEXECPREFIX is prefix/lib/gcc/ where prefix is the prefix to the\ninstalled  compiler.  In  many  cases  prefix  is  the value of \"prefix\" when you ran the\nconfigure script.\n\nOther prefixes specified with -B take precedence over this prefix.\n\nThis prefix is also used for finding files such as crt0.o that are used for linking.\n\nIn addition, the prefix is used in an unusual way in finding the  directories  to  search\nfor  header  files.  For each of the standard directories whose name normally begins with\n/usr/local/lib/gcc (more  precisely,  with  the  value  of  GCCINCLUDEDIR),  GCC  tries\nreplacing  that  beginning  with  the  specified prefix to produce an alternate directory\nname.  Thus, with -Bfoo/, GCC searches foo/bar  just  before  it  searches  the  standard\ndirectory  /usr/local/lib/bar.  If a standard directory begins with the configured prefix\nthen the value of prefix is replaced by GCCEXECPREFIX when looking for header files.\n\nCOMPILERPATH\nThe value of COMPILERPATH is a colon-separated list of directories, much like PATH.  GCC\ntries the directories thus specified when searching for subprograms, if  it  cannot  find\nthe subprograms using GCCEXECPREFIX.\n\nLIBRARYPATH\nThe value of LIBRARYPATH is a colon-separated list of directories, much like PATH.  When\nconfigured  as a native compiler, GCC tries the directories thus specified when searching\nfor special linker files, if it cannot find them using  GCCEXECPREFIX.   Linking  using\nGCC  also  uses these directories when searching for ordinary libraries for the -l option\n(but directories specified with -L come first).\n\nLANG\nThis variable is used to pass locale information to the compiler.  One way in which  this\ninformation is used is to determine the character set to be used when character literals,\nstring literals and comments are parsed in C and C++.  When the compiler is configured to\nallow multibyte characters, the following values for LANG are recognized:\n\nC-JIS\nRecognize JIS characters.\n\nC-SJIS\nRecognize SJIS characters.\n\nC-EUCJP\nRecognize EUCJP characters.\n\nIf LANG is not defined, or if it has some other value, then the compiler uses \"mblen\" and\n\"mbtowc\"  as  defined  by  the  default  locale  to  recognize  and  translate  multibyte\ncharacters.\n\nGCCEXTRADIAGNOSTICOUTPUT\nIf GCCEXTRADIAGNOSTICOUTPUT is set to one of the  following  values,  then  additional\ntext    will    be    emitted    to    stderr    when    fix-it    hints   are   emitted.\n-fdiagnostics-parseable-fixits and -fno-diagnostics-parseable-fixits take precedence over\nthis environment variable.\n\nfixits-v1\nEmit  parseable  fix-it  hints,  equivalent  to  -fdiagnostics-parseable-fixits.   In\nparticular,  columns  are  expressed  as a count of bytes, starting at byte 1 for the\ninitial column.\n\nfixits-v2\nAs  \"fixits-v1\",  but  columns   are   expressed   as   display   columns,   as   per\n-fdiagnostics-column-unit=display.\n\nSome additional environment variables affect the behavior of the preprocessor.\n\nCPATH\nCINCLUDEPATH\nCPLUSINCLUDEPATH\nOBJCINCLUDEPATH\nEach  variable's  value  is  a list of directories separated by a special character, much\nlike PATH, in which to look for header files.  The special  character,  \"PATHSEPARATOR\",\nis  target-dependent  and  determined  at  GCC  build  time.  For Microsoft Windows-based\ntargets it is a semicolon, and for almost all other targets it is a colon.\n\nCPATH specifies a list of directories to be searched as if specified with -I,  but  after\nany  paths  given with -I options on the command line.  This environment variable is used\nregardless of which language is being preprocessed.\n\nThe remaining environment variables apply only when preprocessing the particular language\nindicated.  Each specifies a list of directories to be  searched  as  if  specified  with\n-isystem, but after any paths given with -isystem options on the command line.\n\nIn  all  these  variables,  an empty element instructs the compiler to search its current\nworking directory.  Empty elements can appear at the beginning or end  of  a  path.   For\ninstance,  if  the  value  of  CPATH  is \":/special/include\", that has the same effect as\n-I. -I/special/include.\n\nDEPENDENCIESOUTPUT\nIf this variable is set, its value specifies how to output dependencies for Make based on\nthe non-system header files processed by the compiler.  System header files  are  ignored\nin the dependency output.\n\nThe  value  of  DEPENDENCIESOUTPUT can be just a file name, in which case the Make rules\nare written to that file, guessing the target name from the source  file  name.   Or  the\nvalue  can  have  the  form file target, in which case the rules are written to file file\nusing target as the target name.\n\nIn other words, this environment variable is equivalent to combining the options -MM  and\n-MF, with an optional -MT switch too.\n\nSUNPRODEPENDENCIES\nThis  variable  is the same as DEPENDENCIESOUTPUT (see above), except that system header\nfiles are not ignored, so it implies -M rather than -MM.  However, the dependence on  the\nmain input file is omitted.\n\nSOURCEDATEEPOCH\nIf  this  variable is set, its value specifies a UNIX timestamp to be used in replacement\nof the current date and time in  the  \"DATE\"  and  \"TIME\"  macros,  so  that  the\nembedded timestamps become reproducible.\n\nThe value of SOURCEDATEEPOCH must be a UNIX timestamp, defined as the number of seconds\n(excluding  leap  seconds)  since 01 Jan 1970 00:00:00 represented in ASCII; identical to\nthe output of \"date +%s\" on GNU/Linux and other systems that support the %s extension  in\nthe \"date\" command.\n\nThe value should be a known timestamp such as the last modification time of the source or\npackage and it should be set by the build process.\n",
            "subsections": []
        },
        "BUGS": {
            "content": "For instructions on reporting bugs, see <file:///usr/share/doc/gcc-13/README.Bugs>.\n",
            "subsections": []
        },
        "FOOTNOTES": {
            "content": "1.  On  some  systems, gcc -shared needs to build supplementary stub code for constructors to\nwork.  On multi-libbed systems, gcc -shared must select the correct support libraries  to\nlink against.  Failing to supply the correct flags may lead to subtle defects.  Supplying\nthem in cases where they are not necessary is innocuous.  -shared suppresses the addition\nof  startup code to alter the floating-point environment as done with -ffast-math, -Ofast\nor -funsafe-math-optimizations on some targets.\n",
            "subsections": []
        },
        "SEE ALSO": {
            "content": "gpl(7), gfdl(7), fsf-funding(7), cpp(1), gcov(1), as(1), ld(1), gdb(1) and the  Info  entries\nfor gcc, cpp, as, ld, binutils and gdb.\n",
            "subsections": []
        },
        "AUTHOR": {
            "content": "See  the  Info  entry for gcc, or <https://gcc.gnu.org/onlinedocs/gcc/Contributors.html>, for\ncontributors to GCC.\n",
            "subsections": []
        },
        "COPYRIGHT": {
            "content": "Copyright (c) 1988-2023 Free Software Foundation, Inc.\n\nPermission is granted to copy, distribute and/or modify this document under the terms of  the\nGNU  Free  Documentation  License,  Version  1.3  or  any later version published by the Free\nSoftware Foundation; with the Invariant Sections  being  \"GNU  General  Public  License\"  and\n\"Funding Free Software\", the Front-Cover texts being (a) (see below), and with the Back-Cover\nTexts being (b) (see below).  A copy of the license is included in the gfdl(7) man page.\n\n(a) The FSF's Front-Cover Text is:\n\nA GNU Manual\n\n(b) The FSF's Back-Cover Text is:\n\nYou have freedom to copy and modify this GNU Manual, like GNU\nsoftware.  Copies published by the Free Software Foundation raise\nfunds for GNU development.\n\ngcc-13                                       2024-09-04                                       GCC(1)",
            "subsections": []
        }
    },
    "summary": "gcc - GNU project C and C++ compiler",
    "flags": [
        {
            "flag": "-x",
            "long": null,
            "arg": null,
            "description": "Specify explicitly the language for the following input files (rather than letting the compiler choose a default based on the file name suffix). This option applies to all following input files until the next -x option. Possible values for language are: c c-header cpp-output c++ c++-header c++-system-header c++-user-header c++-cpp-output objective-c objective-c-header objective-c-cpp-output objective-c++ objective-c++-header objective-c++-cpp-output assembler assembler-with-cpp ada d f77 f77-cpp-input f95 f95-cpp-input go"
        },
        {
            "flag": "-x",
            "long": null,
            "arg": null,
            "description": "Turn off any specification of a language, so that subsequent files are handled according to their file name suffixes (as they are if -x has not been used at all). If you only want some of the stages of compilation, you can use -x (or filename suffixes) to tell gcc where to start, and one of the options -c, -S, or -E to say where gcc is to stop. Note that some combinations (for example, -x cpp-output -E) instruct gcc to do nothing at all."
        },
        {
            "flag": "-c",
            "long": null,
            "arg": null,
            "description": "done. The ultimate output is in the form of an object file for each source file. By default, the object file name for a source file is made by replacing the suffix .c, .i, .s, etc., with .o. Unrecognized input files, not requiring compilation or assembly, are ignored."
        },
        {
            "flag": "-S",
            "long": null,
            "arg": null,
            "description": "of an assembler code file for each non-assembler input file specified. By default, the assembler file name for a source file is made by replacing the suffix .c, .i, etc., with .s. Input files that don't require compilation are ignored."
        },
        {
            "flag": "-E",
            "long": null,
            "arg": null,
            "description": "form of preprocessed source code, which is sent to the standard output. Input files that don't require preprocessing are ignored."
        },
        {
            "flag": "-o",
            "long": null,
            "arg": null,
            "description": "Place the primary output in file file. This applies to whatever sort of output is being produced, whether it be an executable file, an object file, an assembler file or preprocessed C code. If -o is not specified, the default is to put an executable file in a.out, the object file for source.suffix in source.o, its assembler file in source.s, a precompiled header file in source.suffix.gch, and all preprocessed C source on standard output. Though -o names only the primary output, it also affects the naming of auxiliary and dump outputs. See the examples below. Unless overridden, both auxiliary outputs and dump outputs are placed in the same directory as the primary output. In auxiliary outputs, the suffix of the input file is replaced with that of the auxiliary output file type; in dump outputs, the suffix of the dump file is appended to the input file suffix. In compilation commands, the base name of both auxiliary and dump outputs is that of the primary output; in compile and link commands, the primary output name, minus the executable suffix, is combined with the input file name. If both share the same base name, disregarding the suffix, the result of the combination is that base name, otherwise, they are concatenated, separated by a dash. gcc -c foo.c ... will use foo.o as the primary output, and place aux outputs and dumps next to it, e.g., aux file foo.dwo for -gsplit-dwarf, and dump file foo.c.???r.final for -fdump-rtl-final. If a non-linker output file is explicitly specified, aux and dump files by default take the same base name: gcc -c foo.c -o dir/foobar.o ... will name aux outputs dir/foobar.* and dump outputs dir/foobar.c.*. A linker output will instead prefix aux and dump outputs: gcc foo.c bar.c -o dir/foobar ... will generally name aux outputs dir/foobar-foo.* and dir/foobar-bar.*, and dump outputs dir/foobar-foo.c.* and dir/foobar-bar.c.*. The one exception to the above is when the executable shares the base name with the single input: gcc foo.c -o dir/foo ... in which case aux outputs are named dir/foo.* and dump outputs named dir/foo.c.*. The location and the names of auxiliary and dump outputs can be adjusted by the options -dumpbase, -dumpbase-ext, -dumpdir, -save-temps=cwd, and -save-temps=obj."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option sets the base name for auxiliary and dump output files. It does not affect the name of the primary output file. Intermediate outputs, when preserved, are not regarded as primary outputs, but as auxiliary outputs: gcc -save-temps -S foo.c saves the (no longer) temporary preprocessed file in foo.i, and then compiles to the (implied) output file foo.s, whereas: gcc -save-temps -dumpbase save-foo -c foo.c preprocesses to in save-foo.i, compiles to save-foo.s (now an intermediate, thus auxiliary output), and then assembles to the (implied) output file foo.o. Absent this option, dump and aux files take their names from the input file, or from the (non-linker) output file, if one is explicitly specified: dump output files (e.g. those requested by -fdump-* options) with the input name suffix, and aux output files (those requested by other non-dump options, e.g. \"-save-temps\", \"-gsplit-dwarf\", \"-fcallgraph-info\") without it. Similar suffix differentiation of dump and aux outputs can be attained for explicitly- given -dumpbase basename.suf by also specifying -dumpbase-ext .suf. If dumpbase is explicitly specified with any directory component, any dumppfx specification (e.g. -dumpdir or -save-temps=*) is ignored, and instead of appending to it, dumpbase fully overrides it: gcc foo.c -c -o dir/foo.o -dumpbase alt/foo \\ -dumpdir pfx- -save-temps=cwd ... creates auxiliary and dump outputs named alt/foo.*, disregarding dir/ in -o, the ./ prefix implied by -save-temps=cwd, and pfx- in -dumpdir. When -dumpbase is specified in a command that compiles multiple inputs, or that compiles and then links, it may be combined with dumppfx, as specified under -dumpdir. Then, each input file is compiled using the combined dumppfx, and default values for dumpbase and auxdropsuf are computed for each input file: gcc foo.c bar.c -c -dumpbase main ... creates foo.o and bar.o as primary outputs, and avoids overwriting the auxiliary and dump outputs by using the dumpbase as a prefix, creating auxiliary and dump outputs named main-foo.* and main-bar.*. An empty string specified as dumpbase avoids the influence of the output basename in the naming of auxiliary and dump outputs during compilation, computing default values : gcc -c foo.c -o dir/foobar.o -dumpbase \" ... will name aux outputs dir/foo.* and dump outputs dir/foo.c.*. Note how their basenames are taken from the input name, but the directory still defaults to that of the output. The empty-string dumpbase does not prevent the use of the output basename for outputs during linking: gcc foo.c bar.c -o dir/foobar -dumpbase \" -flto ... The compilation of the source files will name auxiliary outputs dir/foo.* and dir/bar.*, and dump outputs dir/foo.c.* and dir/bar.c.*. LTO recompilation during linking will use dir/foobar. as the prefix for dumps and auxiliary files."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When forming the name of an auxiliary (but not a dump) output file, drop trailing auxdropsuf from dumpbase before appending any suffixes. If not specified, this option defaults to the suffix of a default dumpbase, i.e., the suffix of the input file when -dumpbase is not present in the command line, or dumpbase is combined with dumppfx. gcc foo.c -c -o dir/foo.o -dumpbase x-foo.c -dumpbase-ext .c ... creates dir/foo.o as the main output, and generates auxiliary outputs in dir/x-foo.*, taking the location of the primary output, and dropping the .c suffix from the dumpbase. Dump outputs retain the suffix: dir/x-foo.c.*. This option is disregarded if it does not match the suffix of a specified dumpbase, except as an alternative to the executable suffix when appending the linker output base name to dumppfx, as specified below: gcc foo.c bar.c -o main.out -dumpbase-ext .out ... creates main.out as the primary output, and avoids overwriting the auxiliary and dump outputs by using the executable name minus auxdropsuf as a prefix, creating auxiliary outputs named main-foo.* and main-bar.* and dump outputs named main-foo.c.* and main-bar.c.*."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When forming the name of an auxiliary or dump output file, use dumppfx as a prefix: gcc -dumpdir pfx- -c foo.c ... creates foo.o as the primary output, and auxiliary outputs named pfx-foo.*, combining the given dumppfx with the default dumpbase derived from the default primary output, derived in turn from the input name. Dump outputs also take the input name suffix: pfx-foo.c.*. If dumppfx is to be used as a directory name, it must end with a directory separator: gcc -dumpdir dir/ -c foo.c -o obj/bar.o ... creates obj/bar.o as the primary output, and auxiliary outputs named dir/bar.*, combining the given dumppfx with the default dumpbase derived from the primary output name. Dump outputs also take the input name suffix: dir/bar.c.*. It defaults to the location of the output file, unless the output file is a special file like \"/dev/null\". Options -save-temps=cwd and -save-temps=obj override this default, just like an explicit -dumpdir option. In case multiple such options are given, the last one prevails: gcc -dumpdir pfx- -c foo.c -save-temps=obj ... outputs foo.o, with auxiliary outputs named foo.* because -save-temps=* overrides the dumppfx given by the earlier -dumpdir option. It does not matter that =obj is the default for -save-temps, nor that the output directory is implicitly the current directory. Dump outputs are named foo.c.*. When compiling from multiple input files, if -dumpbase is specified, dumpbase, minus a auxdropsuf suffix, and a dash are appended to (or override, if containing any directory components) an explicit or defaulted dumppfx, so that each of the multiple compilations gets differently-named aux and dump outputs. gcc foo.c bar.c -c -dumpdir dir/pfx- -dumpbase main ... outputs auxiliary dumps to dir/pfx-main-foo.* and dir/pfx-main-bar.*, appending dumpbase- to dumppfx. Dump outputs retain the input file suffix: dir/pfx-main-foo.c.* and dir/pfx-main-bar.c.*, respectively. Contrast with the single-input compilation: gcc foo.c -c -dumpdir dir/pfx- -dumpbase main ... that, applying -dumpbase to a single source, does not compute and append a separate dumpbase per input file. Its auxiliary and dump outputs go in dir/pfx-main.*. When compiling and then linking from multiple input files, a defaulted or explicitly specified dumppfx also undergoes the dumpbase- transformation above (e.g. the compilation of foo.c and bar.c above, but without -c). If neither -dumpdir nor -dumpbase are given, the linker output base name, minus auxdropsuf, if specified, or the executable suffix otherwise, plus a dash is appended to the default dumppfx instead. Note, however, that unlike earlier cases of linking: gcc foo.c bar.c -dumpdir dir/pfx- -o main ... does not append the output name main to dumppfx, because -dumpdir is explicitly specified. The goal is that the explicitly-specified dumppfx may contain the specified output name as part of the prefix, if desired; only an explicitly-specified -dumpbase would be combined with it, in order to avoid simply discarding a meaningful option. When compiling and then linking from a single input file, the linker output base name will only be appended to the default dumppfx as above if it does not share the base name with the single input file name. This has been covered in single-input linking cases above, but not with an explicit -dumpdir that inhibits the combination, even if overridden by -save-temps=*: gcc foo.c -dumpdir alt/pfx- -o dir/main.exe -save-temps=cwd ... Auxiliary outputs are named foo.*, and dump outputs foo.c.*, in the current working directory as ultimately requested by -save-temps=cwd. Summing it all up for an intuitive though slightly imprecise data flow: the primary output name is broken into a directory part and a basename part; dumppfx is set to the former, unless overridden by -dumpdir or -save-temps=*, and dumpbase is set to the latter, unless overriden by -dumpbase. If there are multiple inputs or linking, this dumpbase may be combined with dumppfx and taken from each input file. Auxiliary output names for each input are formed by combining dumppfx, dumpbase minus suffix, and the auxiliary output suffix; dump output names are only different in that the suffix from dumpbase is retained. When it comes to auxiliary and dump outputs created during LTO recompilation, a combination of dumppfx and dumpbase, as given or as derived from the linker output name but not from inputs, even in cases in which this combination would not otherwise be used as such, is passed down with a trailing period replacing the compiler-added dash, if any, as a -dumpdir option to lto-wrapper; being involved in linking, this program does not normally get any -dumpbase and -dumpbase-ext, and it ignores them. When running sub-compilers, lto-wrapper appends LTO stage names to the received dumppfx, ensures it contains a directory component so that it overrides any -dumpdir, and passes that as -dumpbase to sub-compilers."
        },
        {
            "flag": "-v",
            "long": null,
            "arg": null,
            "description": "Also print the version number of the compiler driver program and of the preprocessor and the compiler proper."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Like -v except the commands are not executed and arguments are quoted unless they contain only alphanumeric characters or \"./-\". This is useful for shell scripts to capture the driver-generated command lines."
        },
        {
            "flag": "",
            "long": "--help",
            "arg": null,
            "description": "Print (on the standard output) a description of the command-line options understood by gcc. If the -v option is also specified then --help is also passed on to the various processes invoked by gcc, so that they can display the command-line options they accept. If the -Wextra option has also been specified (prior to the --help option), then command- line options that have no documentation associated with them are also displayed."
        },
        {
            "flag": "",
            "long": "--target-help",
            "arg": null,
            "description": "Print (on the standard output) a description of target-specific command-line options for each tool. For some targets extra target-specific information may also be printed. --help={class|[^]qualifier}[,...] Print (on the standard output) a description of the command-line options understood by the compiler that fit into all specified classes and qualifiers. These are the supported classes: optimizers Display all of the optimization options supported by the compiler. warnings Display all of the options controlling warning messages produced by the compiler. target Display target-specific options. Unlike the --target-help option however, target- specific options of the linker and assembler are not displayed. This is because those tools do not currently support the extended --help= syntax. params Display the values recognized by the --param option. language Display the options supported for language, where language is the name of one of the languages supported in this version of GCC. If an option is supported by all languages, one needs to select common class. common Display the options that are common to all languages. These are the supported qualifiers: undocumented Display only those options that are undocumented. joined Display options taking an argument that appears after an equal sign in the same continuous piece of text, such as: --help=target. separate Display options taking an argument that appears as a separate word following the original option, such as: -o output-file. Thus for example to display all the undocumented target-specific switches supported by the compiler, use: --help=target,undocumented The sense of a qualifier can be inverted by prefixing it with the ^ character, so for example to display all binary warning options (i.e., ones that are either on or off and that do not take an argument) that have a description, use: --help=warnings,^joined,^undocumented The argument to --help= should not consist solely of inverted qualifiers. Combining several classes is possible, although this usually restricts the output so much that there is nothing to display. One case where it does work, however, is when one of the classes is target. For example, to display all the target-specific optimization options, use: --help=target,optimizers The --help= option can be repeated on the command line. Each successive use displays its requested class of options, skipping those that have already been displayed. If --help is also specified anywhere on the command line then this takes precedence over any --help= option. If the -Q option appears on the command line before the --help= option, then the descriptive text displayed by --help= is changed. Instead of describing the displayed options, an indication is given as to whether the option is enabled, disabled or set to a specific value (assuming that the compiler knows this at the point where the --help= option is used). Here is a truncated example from the ARM port of gcc: % gcc -Q -mabi=2 --help=target -c The following options are target specific: -mabi= 2 -mabort-on-noreturn [disabled] -mapcs [disabled] The output is sensitive to the effects of previous command-line options, so for example it is possible to find out which optimizations are enabled at -O2 by using: -Q -O2 --help=optimizers Alternatively you can discover which binary optimizations are enabled by -O3 by using: gcc -c -Q -O3 --help=optimizers > /tmp/O3-opts gcc -c -Q -O2 --help=optimizers > /tmp/O2-opts diff /tmp/O2-opts /tmp/O3-opts | grep enabled"
        },
        {
            "flag": "",
            "long": "--version",
            "arg": null,
            "description": "Display the version number and copyrights of the invoked GCC."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Normally the gcc program exits with the code of 1 if any phase of the compiler returns a non-success return code. If you specify -pass-exit-codes, the gcc program instead returns with the numerically highest error produced by any phase returning an error indication. The C, C++, and Fortran front ends return 4 if an internal compiler error is encountered."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use pipes rather than temporary files for communication between the various stages of compilation. This fails to work on some systems where the assembler is unable to read from a pipe; but the GNU assembler has no trouble."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Process file after the compiler reads in the standard specs file, in order to override the defaults which the gcc driver program uses when determining what switches to pass to cc1, cc1plus, as, ld, etc. More than one -specs=file can be specified on the command line, and they are processed in order, from left to right."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Invoke all subcommands under a wrapper program. The name of the wrapper program and its parameters are passed as a comma separated list. gcc -c t.c -wrapper gdb,--args This invokes all subprograms of gcc under gdb --args, thus the invocation of cc1 is gdb --args cc1 ...."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When compiling files residing in directory old, record any references to them in the result of the compilation as if the files resided in directory new instead. Specifying this option is equivalent to specifying all the individual -f*-prefix-map options. This can be used to make reproducible builds that are location independent. Directories referenced by directives are not affected by these options. See also -fmacro-prefix-map, -fdebug-prefix-map, -fprofile-prefix-map and -fcanon-prefix-map."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "For the -f*-prefix-map options normally comparison of old prefix against the filename that would be normally referenced in the result of the compilation is done using textual comparison of the prefixes, or ignoring character case for case insensitive filesystems and considering slashes and backslashes as equal on DOS based filesystems. The -fcanon-prefix-map causes such comparisons to be done on canonicalized paths of old and the referenced filename."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Load the plugin code in file name.so, assumed to be a shared object to be dlopen'd by the compiler. The base name of the shared object file is used to identify the plugin for the purposes of argument parsing (See -fplugin-arg-name-key=value below). Each plugin should define the callback functions specified in the Plugins API."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Define an argument called key with a value of value for the plugin called name."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "For C and C++ source and include files, generate corresponding Ada specs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "In conjunction with -fdump-ada-spec[-slim] above, generate Ada specs as child units of parent unit."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "For input files in any language, generate corresponding Go declarations in file. This generates Go \"const\", \"type\", \"var\", and \"func\" declarations which may be a useful way to start writing a Go interface to code written in some other language. @file Read command-line options from file. The options read are inserted in place of the original @file option. If file does not exist, or cannot be read, then the option will be treated literally, and not removed. Options in file are separated by whitespace. A whitespace character may be included in an option by surrounding the entire option in either single or double quotes. Any character (including a backslash) may be included by prefixing the character to be included with a backslash. The file may itself contain additional @file options; any such options will be processed recursively."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "In C mode, this is equivalent to -std=c90. In C++ mode, it is equivalent to -std=c++98. This turns off certain features of GCC that are incompatible with ISO C90 (when compiling C code), or of standard C++ (when compiling C++ code), such as the \"asm\" and \"typeof\" keywords, and predefined macros such as \"unix\" and \"vax\" that identify the type of system you are using. It also enables the undesirable and rarely used ISO trigraph feature. For the C compiler, it disables recognition of C++ style // comments as well as the \"inline\" keyword. The alternate keywords \"asm\", \"extension\", \"inline\" and \"typeof\" continue to work despite -ansi. You would not want to use them in an ISO C program, of course, but it is useful to put them in header files that might be included in compilations done with -ansi. Alternate predefined macros such as \"unix\" and \"vax\" are also available, with or without -ansi. The -ansi option does not cause non-ISO programs to be rejected gratuitously. For that, -Wpedantic is required in addition to -ansi. The macro \"STRICTANSI\" is predefined when the -ansi option is used. Some header files may notice this macro and refrain from declaring certain functions or defining certain macros that the ISO standard doesn't call for; this is to avoid interfering with any programs that might use these names for other things. Functions that are normally built in but do not have semantics defined by ISO C (such as \"alloca\" and \"ffs\") are not built-in functions when -ansi is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Determine the language standard. This option is currently only supported when compiling C or C++. The compiler can accept several base standards, such as c90 or c++98, and GNU dialects of those standards, such as gnu90 or gnu++98. When a base standard is specified, the compiler accepts all programs following that standard plus those using GNU extensions that do not contradict it. For example, -std=c90 turns off certain features of GCC that are incompatible with ISO C90, such as the \"asm\" and \"typeof\" keywords, but not other GNU extensions that do not have a meaning in ISO C90, such as omitting the middle term of a \"?:\" expression. On the other hand, when a GNU dialect of a standard is specified, all features supported by the compiler are enabled, even when those features change the meaning of the base standard. As a result, some strict-conforming programs may be rejected. The particular standard is used by -Wpedantic to identify which features are GNU extensions given that version of the standard. For example -std=gnu90 -Wpedantic warns about C++ style // comments, while -std=gnu99 -Wpedantic does not. A value for this option must be provided; possible values are c90 c89 iso9899:1990 Support all ISO C90 programs (certain GNU extensions that conflict with ISO C90 are disabled). Same as -ansi for C code. iso9899:199409 ISO C90 as modified in amendment 1. c99 c9x iso9899:1999 iso9899:199x ISO C99. This standard is substantially completely supported, modulo bugs and floating-point issues (mainly but not entirely relating to optional C99 features from Annexes F and G). See <https://gcc.gnu.org/c99status.html> for more information. The names c9x and iso9899:199x are deprecated. c11 c1x iso9899:2011 ISO C11, the 2011 revision of the ISO C standard. This standard is substantially completely supported, modulo bugs, floating-point issues (mainly but not entirely relating to optional C11 features from Annexes F and G) and the optional Annexes K (Bounds-checking interfaces) and L (Analyzability). The name c1x is deprecated. c17 c18 iso9899:2017 iso9899:2018 ISO C17, the 2017 revision of the ISO C standard (published in 2018). This standard is same as C11 except for corrections of defects (all of which are also applied with -std=c11) and a new value of \"STDCVERSION\", and so is supported to the same extent as C11. c2x The next version of the ISO C standard, still under development. The support for this version is experimental and incomplete. gnu90 gnu89 GNU dialect of ISO C90 (including some C99 features). gnu99 gnu9x GNU dialect of ISO C99. The name gnu9x is deprecated. gnu11 gnu1x GNU dialect of ISO C11. The name gnu1x is deprecated. gnu17 gnu18 GNU dialect of ISO C17. This is the default for C code. gnu2x The next version of the ISO C standard, still under development, plus GNU extensions. The support for this version is experimental and incomplete. c++98 c++03 The 1998 ISO C++ standard plus the 2003 technical corrigendum and some additional defect reports. Same as -ansi for C++ code. gnu++98 gnu++03 GNU dialect of -std=c++98. c++11 c++0x The 2011 ISO C++ standard plus amendments. The name c++0x is deprecated. gnu++11 gnu++0x GNU dialect of -std=c++11. The name gnu++0x is deprecated. c++14 c++1y The 2014 ISO C++ standard plus amendments. The name c++1y is deprecated. gnu++14 gnu++1y GNU dialect of -std=c++14. The name gnu++1y is deprecated. c++17 c++1z The 2017 ISO C++ standard plus amendments. The name c++1z is deprecated. gnu++17 gnu++1z GNU dialect of -std=c++17. This is the default for C++ code. The name gnu++1z is deprecated. c++20 c++2a The 2020 ISO C++ standard plus amendments. Support is experimental, and could change in incompatible ways in future releases. The name c++2a is deprecated. gnu++20 gnu++2a GNU dialect of -std=c++20. Support is experimental, and could change in incompatible ways in future releases. The name gnu++2a is deprecated. c++2b c++23 The next revision of the ISO C++ standard, planned for 2023. Support is highly experimental, and will almost certainly change in incompatible ways in future releases. gnu++2b gnu++23 GNU dialect of -std=c++2b. Support is highly experimental, and will almost certainly change in incompatible ways in future releases."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Output to the given filename prototyped declarations for all functions declared and/or defined in a translation unit, including those in header files. This option is silently ignored in any language other than C. Besides declarations, the file indicates, in comments, the origin of each declaration (source file and line), whether the declaration was implicit, prototyped or unprototyped (I, N for new or O for old, respectively, in the first character after the line number and the colon), and whether it came from a declaration or a definition (C or F, respectively, in the following character). In the case of function definitions, a K&R-style list of arguments followed by their declarations is also provided, inside comments, after the declaration."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not recognize \"asm\", \"inline\" or \"typeof\" as a keyword, so that code can use these words as identifiers. You can use the keywords \"asm\", \"inline\" and \"typeof\" instead. In C, -ansi implies -fno-asm. In C++, \"inline\" is a standard keyword and is not affected by this switch. You may want to use the -fno-gnu-keywords flag instead, which disables \"typeof\" but not \"asm\" and \"inline\". In C99 mode (-std=c99 or -std=gnu99), this switch only affects the \"asm\" and \"typeof\" keywords, since \"inline\" is a standard keyword in ISO C99. In C2X mode (-std=c2x or -std=gnu2x), this switch only affects the \"asm\" keyword, since \"typeof\" is a standard keyword in ISO C2X."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't recognize built-in functions that do not begin with builtin as prefix. GCC normally generates special code to handle certain built-in functions more efficiently; for instance, calls to \"alloca\" may become single instructions which adjust the stack directly, and calls to \"memcpy\" may become inline copy loops. The resulting code is often both smaller and faster, but since the function calls no longer appear as such, you cannot set a breakpoint on those calls, nor can you change the behavior of the functions by linking with a different library. In addition, when a function is recognized as a built-in function, GCC may use information about that function to warn about problems with calls to that function, or to generate more efficient code, even if the resulting code still contains calls to that function. For example, warnings are given with -Wformat for bad calls to \"printf\" when \"printf\" is built in and \"strlen\" is known not to modify global memory. With the -fno-builtin-function option only the built-in function function is disabled. function must not begin with builtin. If a function is named that is not built-in in this version of GCC, this option is ignored. There is no corresponding -fbuiltin-function option; if you wish to enable built-in functions selectively when using -fno-builtin or -ffreestanding, you may define macros such as: #define abs(n) builtinabs ((n)) #define strcpy(d, s) builtinstrcpy ((d), (s))"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow conditional expressions with mismatched types in the second and third arguments. The value of such an expression is void. This option is not supported for C++."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assert that compilation targets a freestanding environment. This implies -fno-builtin. A freestanding environment is one in which the standard library may not exist, and program startup may not necessarily be at \"main\". The most obvious example is an OS kernel. This is equivalent to -fno-hosted."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable parsing of function definitions marked with \"GIMPLE\". This is an experimental feature that allows unit testing of GIMPLE passes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When the option -fgnu-tm is specified, the compiler generates code for the Linux variant of Intel's current Transactional Memory ABI specification document (Revision 1.1, May 6 2009). This is an experimental feature whose interface may change in future versions of GCC, as the official specification changes. Please note that not all architectures are supported for this feature. For more information on GCC's support for transactional memory, Note that the transactional memory feature is not supported with non-call exceptions (-fnon-call-exceptions)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The option -fgnu89-inline tells GCC to use the traditional GNU semantics for \"inline\" functions when in C99 mode. Using this option is roughly equivalent to adding the \"gnuinline\" function attribute to all inline functions. The option -fno-gnu89-inline explicitly tells GCC to use the C99 semantics for \"inline\" when in C99 or gnu99 mode (i.e., it specifies the default behavior). This option is not supported in -std=c90 or -std=gnu90 mode. The preprocessor macros \"GNUCGNUINLINE\" and \"GNUCSTDCINLINE\" may be used to check which semantics are in effect for \"inline\" functions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assert that compilation targets a hosted environment. This implies -fbuiltin. A hosted environment is one in which the entire standard library is available, and in which \"main\" has a return type of \"int\". Examples are nearly everything except a kernel. This is equivalent to -fno-freestanding."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow implicit conversions between vectors with differing numbers of elements and/or incompatible element types. This option should not be used for new code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Accept some non-standard constructs used in Microsoft header files. In C++ code, this allows member names in structures to be similar to previous types declarations. typedef int UOW; struct ABC { UOW UOW; }; Some cases of unnamed fields in structures and unions are only accepted with this option. Note that this option is off for all targets except for x86 targets using ms-abi."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify for which OpenMP and OpenACC offload targets code should be generated. The default behavior, equivalent to -foffload=default, is to generate code for all supported offload targets. The -foffload=disable form generates code only for the host fallback, while -foffload=target-list generates code only for the specified comma-separated list of offload targets. Offload targets are specified in GCC's internal target-triplet format. You can run the compiler with -v to show the list of configured offload targets under \"OFFLOADTARGETNAMES\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -foffload-options=options, GCC passes the specified options to the compilers for all enabled offloading targets. You can specify options that apply only to a specific target or targets by using the -foffload-options=target-list=options form. The target-list is a comma-separated list in the same format as for the -foffload= option. Typical command lines are -foffload-options=-lgfortran -foffload-options=-lm -foffload-options=\"-lgfortran -lm\" -foffload-options=nvptx-none=-latomic -foffload-options=amdgcn-amdhsa=-march=gfx906 -foffload-options=-lm"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable handling of OpenACC directives \"#pragma acc\" in C/C++ and \"!$acc\" in Fortran. When -fopenacc is specified, the compiler generates accelerated code according to the OpenACC Application Programming Interface v2.6 <https://www.openacc.org>. This option implies -pthread, and thus is only supported on targets that have support for -pthread."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify default compute dimensions for parallel offload regions that do not explicitly specify. The geom value is a triple of ':'-separated sizes, in order 'gang', 'worker' and, 'vector'. A size can be omitted, to use a target-specific default value."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable handling of OpenMP directives \"#pragma omp\" in C/C++, \"[[omp::directive(...)]]\" and \"[[omp::sequence(...)]]\" in C++ and \"!$omp\" in Fortran. When -fopenmp is specified, the compiler generates parallel code according to the OpenMP Application Program Interface v4.5 <https://www.openmp.org>. This option implies -pthread, and thus is only supported on targets that have support for -pthread. -fopenmp implies -fopenmp-simd."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable handling of OpenMP's \"simd\", \"declare simd\", \"declare reduction\", \"assume\", \"ordered\", \"scan\", \"loop\" directives and combined or composite directives with \"simd\" as constituent with \"#pragma omp\" in C/C++, \"[[omp::directive(...)]]\" and \"[[omp::sequence(...)]]\" in C++ and \"!$omp\" in Fortran. Other OpenMP directives are ignored."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "In addition to generating SIMD clones for functions marked with the \"declare simd\" directive, GCC also generates clones for functions marked with the OpenMP \"declare target\" directive that are suitable for vectorization when this option is in effect. The device-type may be one of \"none\", \"host\", \"nohost\", and \"any\", which correspond to keywords for the \"devicetype\" clause of the \"declare target\" directive; clones are generated for the intersection of devices specified. -fopenmp-target-simd-clone is equivalent to -fopenmp-target-simd-clone=any and -fno-openmp-target-simd-clone is equivalent to -fopenmp-target-simd-clone=none. At -O2 and higher (but not -Os or -Og) this optimization defaults to -fopenmp-target-simd-clone=nohost; otherwise it is disabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "ISO/IEC TS 18661-3 defines new permissible values for \"FLTEVALMETHOD\" that indicate that operations and constants with a semantic type that is an interchange or extended format should be evaluated to the precision and range of that type. These new values are a superset of those permitted under C99/C11, which does not specify the meaning of other positive values of \"FLTEVALMETHOD\". As such, code conforming to C11 may not have been written expecting the possibility of the new values. -fpermitted-flt-eval-methods specifies whether the compiler should allow only the values of \"FLTEVALMETHOD\" specified in C99/C11, or the extended set of values specified in ISO/IEC TS 18661-3. style is either \"c11\" or \"ts-18661-3\" as appropriate. The default when in a standards compliant mode (-std=c11 or similar) is -fpermitted-flt-eval-methods=c11. The default when in a GNU dialect (-std=gnu11 or similar) is -fpermitted-flt-eval-methods=ts-18661-3."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Accept some non-standard constructs used in Plan 9 code. This enables -fms-extensions, permits passing pointers to structures with anonymous fields to functions that expect pointers to elements of the type of the field, and permits referring to anonymous fields declared using a typedef. This is only supported for C, not C++."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These options control whether a bit-field is signed or unsigned, when the declaration does not use either \"signed\" or \"unsigned\". By default, such a bit-field is signed, because this is consistent: the basic integer types such as \"int\" are signed types."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Let the type \"char\" be signed, like \"signed char\". Note that this is equivalent to -fno-unsigned-char, which is the negative form of -funsigned-char. Likewise, the option -fno-signed-char is equivalent to -funsigned-char."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Let the type \"char\" be unsigned, like \"unsigned char\". Each kind of machine has a default for what \"char\" should be. It is either like \"unsigned char\" by default or like \"signed char\" by default. Ideally, a portable program should always use \"signed char\" or \"unsigned char\" when it depends on the signedness of an object. But many programs have been written to use plain \"char\" and expect it to be signed, or expect it to be unsigned, depending on the machines they were written for. This option, and its inverse, let you make such a program work with the opposite default. The type \"char\" is always a distinct type from each of \"signed char\" or \"unsigned char\", even though its behavior is always just like one of those two."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Control when to treat the trailing array of a structure as a flexible array member for the purpose of accessing the elements of such an array. The positive form is equivalent to -fstrict-flex-arrays=3, which is the strictest. A trailing array is treated as a flexible array member only when it is declared as a flexible array member per C99 standard onwards. The negative form is equivalent to -fstrict-flex-arrays=0, which is the least strict. All trailing arrays of structures are treated as flexible array members."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Control when to treat the trailing array of a structure as a flexible array member for the purpose of accessing the elements of such an array. The value of level controls the level of strictness. The possible values of level are the same as for the \"strictflexarray\" attribute. You can control this behavior for a specific trailing array field of a structure by using the variable attribute \"strictflexarray\" attribute."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the default scalar storage order of structures and unions to the specified endianness. The accepted values are big-endian, little-endian and native for the native endianness of the target (the default). This option is not supported for C++. Warning: the -fsso-struct switch causes GCC to generate code that is not binary compatible with code generated without it if the specified endianness is not the native endianness of the target."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use version n of the C++ ABI. The default is version 0. Version 0 refers to the version conforming most closely to the C++ ABI specification. Therefore, the ABI obtained using version 0 will change in different versions of G++ as ABI bugs are fixed. Version 1 is the version of the C++ ABI that first appeared in G++ 3.2. Version 2 is the version of the C++ ABI that first appeared in G++ 3.4, and was the default through G++ 4.9. Version 3 corrects an error in mangling a constant address as a template argument. Version 4, which first appeared in G++ 4.5, implements a standard mangling for vector types. Version 5, which first appeared in G++ 4.6, corrects the mangling of attribute const/volatile on function pointer types, decltype of a plain decl, and use of a function parameter in the declaration of another parameter. Version 6, which first appeared in G++ 4.7, corrects the promotion behavior of C++11 scoped enums and the mangling of template argument packs, const/staticcast, prefix ++ and --, and a class scope function used as a template argument. Version 7, which first appeared in G++ 4.8, that treats nullptrt as a builtin type and corrects the mangling of lambdas in default argument scope. Version 8, which first appeared in G++ 4.9, corrects the substitution behavior of function types with function-cv-qualifiers. Version 9, which first appeared in G++ 5.2, corrects the alignment of \"nullptrt\". Version 10, which first appeared in G++ 6.1, adds mangling of attributes that affect type identity, such as ia32 calling convention attributes (e.g. stdcall). Version 11, which first appeared in G++ 7, corrects the mangling of sizeof... expressions and operator names. For multiple entities with the same name within a function, that are declared in different scopes, the mangling now changes starting with the twelfth occurrence. It also implies -fnew-inheriting-ctors. Version 12, which first appeared in G++ 8, corrects the calling conventions for empty classes on the x8664 target and for classes with only deleted copy/move constructors. It accidentally changes the calling convention for classes with a deleted copy constructor and a trivial move constructor. Version 13, which first appeared in G++ 8.2, fixes the accidental change in version 12. Version 14, which first appeared in G++ 10, corrects the mangling of the nullptr expression. Version 15, which first appeared in G++ 10.3, corrects G++ 10 ABI tag regression. Version 16, which first appeared in G++ 11, changes the mangling of \"alignof\" to be distinct from that of \"alignof\", and dependent operator names. Version 17, which first appeared in G++ 12, fixes layout of classes that inherit from aggregate classes with default member initializers in C++14 and up. Version 18, which first appeard in G++ 13, fixes manglings of lambdas that have additional context. See also -Wabi."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On targets that support strong aliases, G++ works around mangling changes by creating an alias with the correct mangled name when defining a symbol with an incorrect mangled name. This switch specifies which ABI version to use for the alias. With -fabi-version=0 (the default), this defaults to 13 (GCC 8.2 compatibility). If another ABI version is explicitly selected, this defaults to 0. For compatibility with GCC versions 3.2 through 4.9, use -fabi-compat-version=2. If this option is not provided but -Wabi=n is, that version is used for compatibility aliases. If this option is provided along with -Wabi (without the version), the version from this option is used for the warning."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Turn off all access checking. This switch is mainly useful for working around bugs in the access control code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable support for C++17 \"new\" of types that require more alignment than \"void* ::operator new(std::sizet)\" provides. A numeric argument such as \"-faligned-new=32\" can be used to specify how much alignment (in bytes) is provided by that function, but few users will need to override the default of alignof(std::maxalignt). This flag is enabled by default for -std=c++17."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable support for \"char8t\" as adopted for C++20. This includes the addition of a new \"char8t\" fundamental type, changes to the types of UTF-8 string and character literals, new signatures for user-defined literals, associated standard library updates, and new \"cppchar8t\" and \"cpplibchar8t\" feature test macros. This option enables functions to be overloaded for ordinary and UTF-8 strings: int f(const char *); // #1 int f(const char8t *); // #2 int v1 = f(\"text\"); // Calls #1 int v2 = f(u8\"text\"); // Calls #2 and introduces new signatures for user-defined literals: int operator\"\"udl1(char8t); int v3 = u8'x'udl1; int operator\"\"udl2(const char8t*, std::sizet); int v4 = u8\"text\"udl2; template<typename T, T...> int operator\"\"udl3(); int v5 = u8\"text\"udl3; The change to the types of UTF-8 string and character literals introduces incompatibilities with ISO C++11 and later standards. For example, the following code is well-formed under ISO C++11, but is ill-formed when -fchar8t is specified. const char *cp = u8\"xx\";// error: invalid conversion from // `const char8t*' to `const char*' int f(const char*); auto v = f(u8\"xx\"); // error: invalid conversion from // `const char8t*' to `const char*' std::string s{u8\"xx\"}; // error: no matching function for call to // `std::basicstring<char>::basicstring()' using namespace std::literals; s = u8\"xx\"s; // error: conversion from // `basicstring<char8t>' to non-scalar // type `basicstring<char>' requested"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Check that the pointer returned by \"operator new\" is non-null before attempting to modify the storage allocated. This check is normally unnecessary because the C++ standard specifies that \"operator new\" only returns 0 if it is declared throw(), in which case the compiler always checks the return value even without this option. In all other cases, when \"operator new\" has a non-empty exception specification, memory exhaustion is signalled by throwing \"std::badalloc\". See also new (nothrow)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable support for the C++ Concepts feature for constraining template arguments. With -std=c++20 and above, Concepts are part of the language standard, so -fconcepts defaults to on. Some constructs that were allowed by the earlier C++ Extensions for Concepts Technical Specification, ISO 19217 (2015), but didn't make it into the standard, can additionally be enabled by -fconcepts-ts."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the maximum nested evaluation depth for C++11 constexpr functions to n. A limit is needed to detect endless recursion during constant expression evaluation. The minimum specified by the standard is 512."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the maximum level of nested evaluation depth for C++11 constexpr functions that will be cached to n. This is a heuristic that trades off compilation speed (when the cache avoids repeated calculations) against memory consumption (when the cache grows very large from highly recursive evaluations). The default is 8. Very few users are likely to want to adjust it, but if your code does heavy constexpr calculations you might want to experiment to find which value works best for you."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Annex F of the C standard specifies that IEC559 floating point exceptions encountered at compile time should not stop compilation. C++ compilers have historically not followed this guidance, instead treating floating point division by zero as non-constant even though it has a well defined value. This flag tells the compiler to give Annex F priority over other rules saying that a particular operation is undefined. constexpr float inf = 1./0.; // OK with -fconstexpr-fp-except"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the maximum number of iterations for a loop in C++14 constexpr functions to n. A limit is needed to detect infinite loops during constant expression evaluation. The default is 262144 (1<<18)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the maximum number of operations during a single constexpr evaluation. Even when number of iterations of a single loop is limited with the above limit, if there are several nested loops and each of them has many iterations but still smaller than the above limit, or if in a body of some loop or even outside of a loop too many expressions need to be evaluated, the resulting constexpr evaluation might take too long. The default is 33554432 (1<<25)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable experimental support for the C++ Contracts feature, as briefly added to and then removed from the C++20 working paper (N4820). The implementation also includes proposed enhancements from papers P1290, P1332, and P1429. This functionality is intended mostly for those interested in experimentation towards refining the feature to get it into shape for a future C++ standard. On violation of a checked contract, the violation handler is called. Users can replace the violation handler by defining void handlecontractviolation (const std::experimental::contractviolation&); There are different sets of additional flags that can be used together to specify which contracts will be checked and how, for N4820 contracts, P1332 contracts, or P1429 contracts; these sets cannot be used together. -fcontract-mode=[on|off] Control whether any contracts have any semantics at all. Defaults to on. -fcontract-assumption-mode=[on|off] [N4820] Control whether contracts with level axiom should have the assume semantic. Defaults to on. -fcontract-build-level=[off|default|audit] [N4820] Specify which level of contracts to generate checks for. Defaults to default. -fcontract-continuation-mode=[on|off] [N4820] Control whether to allow the program to continue executing after a contract violation. That is, do checked contracts have the maybe semantic described below rather than the never semantic. Defaults to off. -fcontract-role=<name>:<default>,<audit>,<axiom> [P1332] Specify the concrete semantics for each contract level of a particular contract role. -fcontract-semantic=[default|audit|axiom]:<semantic> [P1429] Specify the concrete semantic for a particular contract level. -fcontract-strict-declarations=[on|off] Control whether to reject adding contracts to a function after its first declaration. Defaults to off. The possible concrete semantics for that can be specified with -fcontract-role or -fcontract-semantic are: \"ignore\" This contract has no effect. \"assume\" This contract is treated like C++23 \"[[assume]]\". \"checknevercontinue\" \"never\" \"abort\" This contract is checked. If it fails, the violation handler is called. If the handler returns, \"std::terminate\" is called. \"checkmaybecontinue\" \"maybe\" This contract is checked. If it fails, the violation handler is called. If the handler returns, execution continues normally."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable support for the C++ coroutines extension (experimental)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The C++ standard allows an implementation to omit creating a temporary that is only used to initialize another object of the same type. Specifying this option disables that optimization, and forces G++ to call the copy constructor in all cases. This option also causes G++ to call trivial member functions which otherwise would be expanded inline. In C++17, the compiler is required to omit these temporaries, but this option still affects trivial member functions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't generate code to check for violation of exception specifications at run time. This option violates the C++ standard, but may be useful for reducing code size in production builds, much like defining \"NDEBUG\". This does not give user code permission to throw exceptions in violation of the exception specifications; the compiler still optimizes based on the specifications, so throwing an unexpected exception results in undefined behavior at run time."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The C++11 and OpenMP standards allow \"threadlocal\" and \"threadprivate\" variables to have dynamic (runtime) initialization. To support this, any use of such a variable goes through a wrapper function that performs any necessary initialization. When the use and definition of the variable are in the same translation unit, this overhead can be optimized away, but when the use is in a different translation unit there is significant overhead even if the variable doesn't actually need dynamic initialization. If the programmer can be sure that no use of the variable in a non-defining TU needs to trigger dynamic initialization (either because the variable is statically initialized, or a use of the variable in the defining TU will be executed before any uses in another TU), they can avoid this overhead with the -fno-extern-tls-init option. On targets that support symbol aliases, the default is -fextern-tls-init. On targets that do not support symbol aliases, the default is -fno-extern-tls-init."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Permit the C++ frontend to fold calls to \"std::move\", \"std::forward\", \"std::addressof\" and \"std::asconst\". In contrast to inlining, this means no debug information will be generated for such calls. Since these functions are rarely interesting to debug, this flag is enabled by default unless -fno-inline is active."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not recognize \"typeof\" as a keyword, so that code can use this word as an identifier. You can use the keyword \"typeof\" instead. This option is implied by the strict ISO C++ dialects: -ansi, -std=c++98, -std=c++11, etc."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Make inline functions implicitly constexpr, if they satisfy the requirements for a constexpr function. This option can be used in C++14 mode or later. This can result in initialization changing from dynamic to static and other optimizations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Never emit code for non-inline templates that are instantiated implicitly (i.e. by use); only emit code for explicit instantiations. If you use this option, you must take care to structure your code to include all the necessary explicit instantiations to avoid getting undefined symbols at link time."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't emit code for implicit instantiations of inline templates, either. The default is to handle inlines differently so that compiles with and without optimization need the same set of explicit instantiations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "To save space, do not emit out-of-line copies of inline functions controlled by \"#pragma implementation\". This causes linker errors if these functions are not inlined everywhere they are called."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable support for C++20 modules. The -fno-modules-ts is usually not needed, as that is the default. Even though this is a C++20 feature, it is not currently implicitly enabled by selecting that standard version."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Compile a header file to create an importable header unit."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Member functions defined in their class definitions are not implicitly inline for modular code. This is different to traditional C++ behavior, for good reasons. However, it may result in a difficulty during code porting. This option makes such function definitions implicitly inline. It does however generate an ABI incompatibility, so you must use it everywhere or nowhere. (Such definitions outside of a named module remain implicitly inline, regardless.)"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable lazy module importing and module mapper creation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "An oracle to query for module name to filename mappings. If unspecified the CXXMODULEMAPPER environment variable is used, and if that is unset, an in-process default is provided."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Only emit the Compiled Module Interface, inhibiting any object file."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable Wpedantic warnings about constructs used in MFC, such as implicit int and getting a pointer to member function via non-standard syntax."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the P0136 adjustment to the semantics of C++11 constructor inheritance. This is part of C++17 but also considered to be a Defect Report against C++11 and C++14. This flag is enabled by default unless -fabi-version=10 or lower is specified."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the P0522 resolution to Core issue 150, template template parameters and default arguments: this allows a template with default template arguments as an argument for a template template parameter with fewer template parameters. This flag is enabled by default for -std=c++17."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable built-in declarations of functions that are not mandated by ANSI/ISO C. These include \"ffs\", \"alloca\", \"exit\", \"index\", \"bzero\", \"conjf\", and other related functions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Treat a throw() exception specification as if it were a \"noexcept\" specification to reduce or eliminate the text size overhead relative to a function with no exception specification. If the function has local variables of types with non-trivial destructors, the exception specification actually makes the function smaller because the EH cleanups for those variables can be optimized away. The semantic effect is that an exception thrown out of a function with such an exception specification results in a call to \"terminate\" rather than \"unexpected\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not treat the operator name keywords \"and\", \"bitand\", \"bitor\", \"compl\", \"not\", \"or\" and \"xor\" as synonyms as keywords."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable diagnostics that the standard says a compiler does not need to issue. Currently, the only such diagnostic issued by G++ is the one for a name having multiple meanings within a class."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Downgrade some diagnostics about nonconformant code from errors to warnings. Thus, using -fpermissive allows some nonconforming code to compile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When an error message refers to a specialization of a function template, the compiler normally prints the signature of the template followed by the template arguments and any typedefs or typenames in the signature (e.g. \"void f(T) [with T = int]\" rather than \"void f(int)\") so that it's clear which template is involved. When an error message refers to a specialization of a class template, the compiler omits any template arguments that match the default template arguments for that template. If either of these behaviors make it harder to understand the error message rather than easier, you can use -fno-pretty-templates to disable them."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable generation of information about every class with virtual functions for use by the C++ run-time type identification features (\"dynamiccast\" and \"typeid\"). If you don't use those parts of the language, you can save some space by using this flag. Note that exception handling uses the same information, but G++ generates it as needed. The \"dynamiccast\" operator can still be used for casts that do not require run-time type information, i.e. casts to \"void *\" or to unambiguous base classes. Mixing code compiled with -frtti with that compiled with -fno-rtti may not work. For example, programs may fail to link if a class compiled with -fno-rtti is used as a base for a class compiled with -frtti."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the built-in global declarations void operator delete (void *, std::sizet) noexcept; void operator delete[] (void *, std::sizet) noexcept; as introduced in C++14. This is useful for user-defined replacement deallocation functions that, for example, use the size of the object to make deallocation faster. Enabled by default under -std=c++14 and above. The flag -Wsized-deallocation warns about places that might want to add a definition."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow the compiler to optimize using the assumption that a value of enumerated type can only be one of the values of the enumeration (as defined in the C++ standard; basically, a value that can be represented in the minimum number of bits needed to represent all the enumerators). This assumption may not be valid if the program uses a cast to convert an arbitrary integer value to the enumerated type."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Evaluate member access, array subscripting, and shift expressions in left-to-right order, and evaluate assignment in right-to-left order, as adopted for C++17. Enabled by default with -std=c++17. -fstrong-eval-order=some enables just the ordering of member access and shift expressions, and is the default without -std=c++17."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the maximum number of template instantiation notes for a single warning or error to n. The default value is 10."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the maximum instantiation depth for template classes to n. A limit on the template instantiation depth is needed to detect endless recursions during template class instantiation. ANSI/ISO C++ conforming programs must not rely on a maximum depth greater than 17 (changed to 1024 in C++11). The default value is 900, as the compiler can run out of stack space before hitting 1024 in some situations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not emit the extra code to use the routines specified in the C++ ABI for thread-safe initialization of local statics. You can use this option to reduce code size slightly in code that doesn't need to be thread-safe."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Register destructors for objects with static storage duration with the \"cxaatexit\" function rather than the \"atexit\" function. This option is required for fully standards- compliant handling of static destructors, but only works if your C library supports \"cxaatexit\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't use the \"cxagetexceptionptr\" runtime routine. This causes \"std::uncaughtexception\" to be incorrect, but is necessary if the runtime routine is not available."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This switch declares that the user does not attempt to compare pointers to inline functions or methods where the addresses of the two functions are taken in different shared objects. The effect of this is that GCC may, effectively, mark inline methods with \"attribute ((visibility (\"hidden\")))\" so that they do not appear in the export table of a DSO and do not require a PLT indirection when used within the DSO. Enabling this option can have a dramatic effect on load and link times of a DSO as it massively reduces the size of the dynamic export table when the library makes heavy use of templates. The behavior of this switch is not quite the same as marking the methods as hidden directly, because it does not affect static variables local to the function or cause the compiler to deduce that the function is defined in only one shared object. You may mark a method as having a visibility explicitly to negate the effect of the switch for that method. For example, if you do want to compare pointers to a particular inline method, you might mark it as having default visibility. Marking the enclosing class with explicit visibility has no effect. Explicitly instantiated inline methods are unaffected by this option as their linkage might otherwise cross a shared library boundary."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This flag attempts to use visibility settings to make GCC's C++ linkage model compatible with that of Microsoft Visual Studio. The flag makes these changes to GCC's linkage model: 1. It sets the default visibility to \"hidden\", like -fvisibility=hidden. 2. Types, but not their members, are not hidden by default. 3. The One Definition Rule is relaxed for types without explicit visibility specifications that are defined in more than one shared object: those declarations are permitted if they are permitted when this option is not used. In new code it is better to use -fvisibility=hidden and export those classes that are intended to be externally visible. Unfortunately it is possible for code to rely, perhaps accidentally, on the Visual Studio behavior. Among the consequences of these changes are that static data members of the same type with the same name but defined in different shared objects are different, so changing one does not change the other; and that pointers to function members defined in different shared objects may not compare equal. When this flag is given, it is a violation of the ODR to define types with the same name differently."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use weak symbol support, even if it is provided by the linker. By default, G++ uses weak symbols if they are available. This option exists only for testing, and should not be used by end-users; it results in inferior code and has no benefits. This option may be removed in a future release of G++."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Accept imaginary, fixed-point, or machine-defined literal number suffixes as GNU extensions. When this option is turned off these suffixes are treated as C++11 user- defined literal numeric suffixes. This is on by default for all pre-C++11 dialects and all GNU dialects: -std=c++98, -std=gnu++98, -std=gnu++11, -std=gnu++14. This option is off by default for ISO C++11 onwards (-std=c++11, ...)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not search for header files in the standard directories specific to C++, but do still search the other standard directories. (This option is used when building the C++ library.)"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Inform of include translation events. The first will note accepted include translations, the second will note declined include translations. The header form will inform of include translations relating to that specific header. If header is of the form \"user\" or \"<system>\" it will be resolved to a specific user or system header using the include path."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Inform of Compiled Module Interface pathnames. The first will note all read CMI pathnames. The module form will not reading a specific module's CMI. module may be a named module or a header-unit (the latter indicated by either being a pathname containing directory separators or enclosed in \"<>\" or \"\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When G++ is configured to support this option, it allows specification of alternate C++ runtime libraries. Two options are available: libstdc++ (the default, native C++ runtime for G++) and libc++ which is the C++ runtime installed on some operating systems (e.g. Darwin versions from Darwin11 onwards). The option switches G++ to use the headers from the specified library and to emit \"-lstdc++\" or \"-lc++\" respectively, when a C++ runtime is required for linking. In addition, these warning options have meanings only for C++ programs:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a type with an ABI tag is used in a context that does not have that ABI tag. See C++ Attributes for more information about ABI tags."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about uses of a comma expression within a subscripting expression. This usage was deprecated in C++20 and is going to be removed in C++23. However, a comma expression wrapped in \"( )\" is not deprecated. Example: void f(int *a, int b, int c) { a[b,c]; // deprecated in C++20, invalid in C++23 a[(b,c)]; // OK } In C++23 it is valid to have comma separated expressions in a subscript when an overloaded subscript operator is found and supports the right number and types of arguments. G++ will accept the formerly valid syntax for code that is not valid in C++23 but used to be valid but deprecated in C++20 with a pedantic warning that can be disabled with -Wno-comma-subscript. Enabled by default with -std=c++20 unless -Wno-deprecated, and with -std=c++23 regardless of -Wno-deprecated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when performing class template argument deduction (CTAD) on a type with no explicitly written deduction guides. This warning will point out cases where CTAD succeeded only because the compiler synthesized the implicit deduction guides, which might not be what the programmer intended. Certain style guides allow CTAD only on types that specifically \"opt-in\"; i.e., on types that are designed to support CTAD. This warning can be suppressed with the following pattern: struct allowctadt; // any name works template <typename T> struct S { S(T) { } }; // Guide with incomplete parameter type will never be considered. S(allowctadt) -> S<void>;"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a class seems unusable because all the constructors or destructors in that class are private, and it has neither friends nor public static member functions. Also warn if there are no non-private methods, and there's at least one private member function that isn't a constructor or destructor."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a reference is bound to a temporary whose lifetime has ended. For example: int n = 1; const int& r = std::max(n - 1, n + 1); // r is dangling In the example above, two temporaries are created, one for each argument, and a reference to one of the temporaries is returned. However, both temporaries are destroyed at the end of the full expression, so the reference \"r\" is dangling. This warning also detects dangling references in member initializer lists: const int& f(const int& i) { return i; } struct S { const int &r; // r is dangling S() : r(f(10)) { } }; Member functions are checked as well, but only their object argument: struct S { const S& self () { return *this; } }; const S& s = S().self(); // s is dangling Certain functions are safe in this respect, for example \"std::usefacet\": they take and return a reference, but they don't return one of its arguments, which can fool the warning. Such functions can be excluded from the warning by wrapping them in a \"#pragma\": #pragma GCC diagnostic push #pragma GCC diagnostic ignored \"-Wdangling-reference\" const T& foo (const T&) { ... } #pragma GCC diagnostic pop -Wdangling-reference also warns about code like auto p = std::minmax(1, 2); where \"std::minmax\" returns \"std::pair<const int&, const int&>\", and both references dangle after the end of the full expression that contains the call to \"std::minmax\". This warning is enabled by -Wextra."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when \"delete\" is used to destroy an instance of a class that has virtual functions and non-virtual destructor. It is unsafe to delete an instance of a derived class through a pointer to a base class if the base class does not have a virtual destructor. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn that the implicit declaration of a copy constructor or copy assignment operator is deprecated if the class has a user-provided copy constructor or copy assignment operator, in C++11 and up. This warning is enabled by -Wextra. With -Wdeprecated-copy-dtor, also deprecate if the class has a user-provided destructor."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable the warning about the case when the usual arithmetic conversions are applied on operands where one is of enumeration type and the other is of a different enumeration type. This conversion was deprecated in C++20. For example: enum E1 { e }; enum E2 { f }; int k = f - e; -Wdeprecated-enum-enum-conversion is enabled by default with -std=c++20. In pre-C++20 dialects, this warning can be enabled by -Wenum-conversion."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable the warning about the case when the usual arithmetic conversions are applied on operands where one is of enumeration type and the other is of a floating-point type. This conversion was deprecated in C++20. For example: enum E1 { e }; enum E2 { f }; bool b = e <= 3.7; -Wdeprecated-enum-float-conversion is enabled by default with -std=c++20. In pre-C++20 dialects, this warning can be enabled by -Wenum-conversion."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn about uses of \"std::initializerlist\" that are likely to result in dangling pointers. Since the underlying array for an \"initializerlist\" is handled like a normal C++ temporary object, it is easy to inadvertently keep a pointer to the array past the end of the array's lifetime. For example: * If a function returns a temporary \"initializerlist\", or a local \"initializerlist\" variable, the array's lifetime ends at the end of the return statement, so the value returned has a dangling pointer. * If a new-expression creates an \"initializerlist\", the array only lives until the end of the enclosing full-expression, so the \"initializerlist\" in the heap has a dangling pointer. * When an \"initializerlist\" variable is assigned from a brace-enclosed initializer list, the temporary array created for the right side of the assignment only lives until the end of the full-expression, so at the next statement the \"initializerlist\" variable has a dangling pointer. // li's initial underlying array lives as long as li std::initializerlist<int> li = { 1,2,3 }; // assignment changes li to point to a temporary array li = { 4, 5 }; // now the temporary is gone and li has a dangling pointer int i = li.begin()[0] // undefined behavior * When a list constructor stores the \"begin\" pointer from the \"initializerlist\" argument, this doesn't extend the lifetime of the array, so if a class variable is constructed from a temporary \"initializerlist\", the pointer is left dangling by the end of the variable declaration statement."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a function never produces a constant expression. In C++20 and earlier, for every \"constexpr\" function and function template, there must be at least one set of function arguments in at least one instantiation such that an invocation of the function or constructor could be an evaluated subexpression of a core constant expression. C++23 removed this restriction, so it's possible to have a function or a function template marked \"constexpr\" for which no invocation satisfies the requirements of a core constant expression. This warning is enabled as a pedantic warning by default in C++20 and earlier. In C++23, -Winvalid-constexpr can be turned on, in which case it will be an ordinary warning. For example: void f (int& i); constexpr void g (int& i) { // Warns by default in C++20, in C++23 only with -Winvalid-constexpr. f(i); }"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Verify all imported macro definitions are valid at the end of compilation. This is not enabled by default, as it requires additional processing to determine. It may be useful when preparing sets of header-units to ensure consistent macros."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn when a string or character literal is followed by a ud-suffix which does not begin with an underscore. As a conforming extension, GCC treats such suffixes as separate preprocessing tokens in order to maintain backwards compatibility with code that uses formatting macros from \"<inttypes.h>\". For example: #define STDCFORMATMACROS #include <inttypes.h> #include <stdio.h> int main() { int64t i64 = 123; printf(\"My int64: %\" PRId64\"\\n\", i64); } In this case, \"PRId64\" is treated as a separate preprocessing token. This option also controls warnings when a user-defined literal operator is declared with a literal suffix identifier that doesn't begin with an underscore. Literal suffix identifiers that don't begin with an underscore are reserved for future standardization. These warnings are enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "For C++11 and later standards, narrowing conversions are diagnosed by default, as required by the standard. A narrowing conversion from a constant produces an error, and a narrowing conversion from a non-constant produces a warning, but -Wno-narrowing suppresses the diagnostic. Note that this does not affect the meaning of well-formed code; narrowing conversions are still considered ill-formed in SFINAE contexts. With -Wnarrowing in C++98, warn when a narrowing conversion prohibited by C++11 occurs within { }, e.g. int i = { 2.2 }; // error: narrowing from double to int This flag is included in -Wall and -Wc++11-compat."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a noexcept-expression evaluates to false because of a call to a function that does not have a non-throwing exception specification (i.e. throw() or \"noexcept\") but is known by the compiler to never throw an exception."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if the C++17 feature making \"noexcept\" part of a function type changes the mangled name of a symbol relative to C++14. Enabled by -Wabi and -Wc++17-compat. As an example: template <class T> void f(T t) { t(); }; void g() noexcept; void h() { f(g); } In C++14, \"f\" calls \"f<void(*)()>\", but in C++17 it calls \"f<void(*)()noexcept>\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when the destination of a call to a raw memory function such as \"memset\" or \"memcpy\" is an object of class type, and when writing into such an object might bypass the class non-trivial or deleted constructor or copy assignment, violate const-correctness or encapsulation, or corrupt virtual table pointers. Modifying the representation of such objects may violate invariants maintained by member functions of the class. For example, the call to \"memset\" below is undefined because it modifies a non-trivial class object and is, therefore, diagnosed. The safe way to either initialize or clear the storage of objects of such types is by using the appropriate constructor or assignment operator, if one is available. std::string str = \"abc\"; memset (&str, 0, sizeof str); The -Wclass-memaccess option is enabled by -Wall. Explicitly casting the pointer to the class object to \"void *\" or to a type that can be safely accessed by the raw memory function suppresses the warning."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a class has virtual functions and an accessible non-virtual destructor itself or in an accessible polymorphic base class, in which case it is possible but unsafe to delete an instance of a derived class through a pointer to the class itself or base class. This warning is automatically enabled if -Weffc++ is specified. The -Wdelete-non-virtual-dtor option (enabled by -Wall) should be preferred because it warns about the unsafe cases without false positives."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn on uses of the \"register\" storage class specifier, except when it is part of the GNU Explicit Register Variables extension. The use of the \"register\" keyword as storage class specifier has been deprecated in C++11 and removed in C++17. Enabled by default with -std=c++17."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when the order of member initializers given in the code does not match the order in which they must be executed. For instance: struct A { int i; int j; A(): j (0), i (1) { } }; The compiler rearranges the member initializers for \"i\" and \"j\" to match the declaration order of the members, emitting a warning to that effect. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning warns when a call to \"std::move\" prevents copy elision. A typical scenario when copy elision can occur is when returning in a function with a class return type, when the expression being returned is the name of a non-volatile automatic object, and is not a function parameter, and has the same type as the function return type. struct T { ... }; T fn() { T t; ... return std::move (t); } But in this example, the \"std::move\" call prevents copy elision. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning warns about redundant calls to \"std::move\"; that is, when a move operation would have been performed even without the \"std::move\" call. This happens because the compiler is forced to treat the object as if it were an rvalue in certain situations such as returning a local variable, where copy elision isn't applicable. Consider: struct T { ... }; T fn(T t) { ... return std::move (t); } Here, the \"std::move\" call is redundant. Because G++ implements Core Issue 1579, another example is: struct T { // convertible to U ... }; struct U { ... }; U fn() { T t; ... return std::move (t); } In this example, copy elision isn't applicable because the type of the expression being returned and the function return type differ, yet G++ treats the return value as if it were designated by an rvalue. This warning is enabled by -Wextra."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning warns when a C++ range-based for-loop is creating an unnecessary copy. This can happen when the range declaration is not a reference, but probably should be. For example: struct S { char arr[128]; }; void fn () { S arr[5]; for (const auto x : arr) { ... } } It does not warn when the type being copied is a trivially-copyable type whose size is less than 64 bytes. This warning also warns when a loop variable in a range-based for-loop is initialized with a value of a different type resulting in a copy. For example: void fn() { int arr[10]; for (const double &x : arr) { ... } } In the example above, in every iteration of the loop a temporary value of type \"double\" is created and destroyed, to which the reference \"const double &\" is bound. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about redundant class-key and enum-key in references to class types and enumerated types in contexts where the key can be eliminated without causing an ambiguity. For example: struct foo; struct foo *p; // warn that keyword struct can be eliminated On the other hand, in this example there is no warning: struct foo; void foo (); // \"hides\" struct foo void bar (struct foo&); // no warning, keyword struct is necessary"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn if a class type has a base or a field whose type uses the anonymous namespace or depends on a type with no linkage. If a type A depends on a type B with no or internal linkage, defining it in multiple translation units would be an ODR violation because the meaning of B is different in each translation unit. If A only appears in a single translation unit, the best way to silence the warning is to give it internal linkage by putting it in an anonymous namespace as well. The compiler doesn't give this warning for types defined in the main .C file, as those are unlikely to have multiple definitions. -Wsubobject-linkage is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about violations of the following style guidelines from Scott Meyers' Effective C++ series of books: * Define a copy constructor and an assignment operator for classes with dynamically- allocated memory. * Prefer initialization to assignment in constructors. * Have \"operator=\" return a reference to *this. * Don't try to return a reference when you must return an object. * Distinguish between prefix and postfix forms of increment and decrement operators. * Never overload \"&&\", \"||\", or \",\". This option also enables -Wnon-virtual-dtor, which is also one of the effective C++ recommendations. However, the check is extended to warn about the lack of virtual destructor in accessible non-polymorphic bases classes too. When selecting this option, be aware that the standard library headers do not obey all of these guidelines; use grep -v to filter out those warnings."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable the warning about the case when an exception handler is shadowed by another handler, which can point out a wrong ordering of exception handlers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about the use of an uncasted \"NULL\" as sentinel. When compiling only with GCC this is a valid sentinel, as \"NULL\" is defined to \"null\". Although it is a null pointer constant rather than a null pointer, it is guaranteed to be of the same size as a pointer. But this use is not portable across different compilers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable warnings when non-template friend functions are declared within a template. In very old versions of GCC that predate implementation of the ISO standard, declarations such as friend int foo(int), where the name of the friend is an unqualified-id, could be interpreted as a particular specialization of a template function; the warning exists to diagnose compatibility problems, and is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if an old-style (C-style) cast to a non-void type is used within a C++ program. The new-style casts (\"dynamiccast\", \"staticcast\", \"reinterpretcast\", and \"constcast\") are less vulnerable to unintended effects and much easier to search for."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a function declaration hides virtual functions from a base class. For example, in: struct A { virtual void f(); }; struct B: public A { void f(int); // does not override }; the \"A\" class version of \"f\" is hidden in \"B\", and code like: B* b; b->f(); fails to compile. In cases where the different signatures are not an accident, the simplest solution is to add a using-declaration to the derived class to un-hide the base function, e.g. add \"using A::f;\" to \"B\". The optional level suffix controls the behavior when all the declarations in the derived class override virtual functions in the base class, even if not all of the base functions are overridden: struct C { virtual void f(); virtual void f(int); }; struct D: public C { void f(int); // does override } This pattern is less likely to be a mistake; if D is only used virtually, the user might have decided that the base class semantics for some of the overloads are fine. At level 1, this case does not warn; at level 2, it does. -Woverloaded-virtual by itself selects level 2. Level 1 is included in -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable the diagnostic for converting a bound pointer to member function to a plain pointer."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when overload resolution chooses a promotion from unsigned or enumerated type to a signed type, over a conversion to an unsigned type of the same size. Previous versions of G++ tried to preserve unsignedness, but the standard mandates the current behavior."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a primary template declaration is encountered. Some coding rules disallow templates, and this may be used to enforce that rule. The warning is inactive inside a system header file, such as the STL, so one can still use the STL. One may also instantiate or specialize templates."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for mismatches between calls to \"operator new\" or \"operator delete\" and the corresponding call to the allocation or deallocation function. This includes invocations of C++ \"operator delete\" with pointers returned from either mismatched forms of \"operator new\", or from other functions that allocate objects for which the \"operator delete\" isn't a suitable deallocator, as well as calls to other deallocation functions with pointers returned from \"operator new\" for which the deallocation function isn't suitable. For example, the \"delete\" expression in the function below is diagnosed because it doesn't match the array form of the \"new\" expression the pointer argument was returned from. Similarly, the call to \"free\" is also diagnosed. void f () { int *a = new int[n]; delete a; // warning: mismatch in array forms of expressions char *p = new char[n]; free (p); // warning: mismatch between new and free } The related option -Wmismatched-dealloc diagnoses mismatches involving allocation and deallocation functions other than \"operator new\" and \"operator delete\". -Wmismatched-new-delete is included in -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for declarations of structs, classes, and class templates and their specializations with a class-key that does not match either the definition or the first declaration if no definition is provided. For example, the declaration of \"struct Object\" in the argument list of \"draw\" triggers the warning. To avoid it, either remove the redundant class-key \"struct\" or replace it with \"class\" to match its definition. class Object { public: virtual ~Object () = 0; }; void draw (struct Object*); It is not wrong to declare a class with the class-key \"struct\" as the example above shows. The -Wmismatched-tags option is intended to help achieve a consistent style of class declarations. In code that is intended to be portable to Windows-based compilers the warning helps prevent unresolved references due to the difference in the mangling of symbols declared with different class-keys. The option can be used either on its own or in conjunction with -Wredundant-tags."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a class is defined with multiple direct base classes. Some coding rules disallow multiple inheritance, and this may be used to enforce that rule. The warning is inactive inside a system header file, such as the STL, so one can still use the STL. One may also define classes that indirectly use multiple inheritance."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a class is defined with a virtual direct base class. Some coding rules disallow multiple inheritance, and this may be used to enforce that rule. The warning is inactive inside a system header file, such as the STL, so one can still use the STL. One may also define classes that indirectly use virtual inheritance."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Suppress warnings about inheriting from a virtual base with a non-trivial C++11 move assignment operator. This is dangerous because if the virtual base is reachable along more than one path, it is moved multiple times, which can mean both objects end up in the moved-from state. If the move assignment operator is written to avoid moving from a moved-from object, this warning can be disabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a namespace definition is opened. Some coding rules disallow namespaces, and this may be used to enforce that rule. The warning is inactive inside a system header file, such as the STL, so one can still use the STL. One may also use using directives and qualified names."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable the warning about a throw-expression that will immediately result in a call to \"terminate\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about the most vexing parse syntactic ambiguity. This warns about the cases when a declaration looks like a variable definition, but the C++ language requires it to be interpreted as a function declaration. For instance: void f(double a) { int i(); // extern int i (void); int n(int(a)); // extern int n (int); } Another example: struct S { S(int); }; void f(double a) { S x(int(a)); // extern struct S x (int); S y(int()); // extern struct S y (int (*) (void)); S z(); // extern struct S z (void); } The warning will suggest options how to deal with such an ambiguity; e.g., it can suggest removing the parentheses or using braces instead. This warning is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn when a conversion function converts an object to the same type, to a base class of that type, or to void; such a conversion function will never be called."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about deprecated uses of the \"volatile\" qualifier. This includes postfix and prefix \"++\" and \"--\" expressions of \"volatile\"-qualified types, using simple assignments where the left operand is a \"volatile\"-qualified non-class type for their value, compound assignments where the left operand is a \"volatile\"-qualified non-class type, \"volatile\"-qualified function return type, \"volatile\"-qualified parameter type, and structured bindings of a \"volatile\"-qualified type. This usage was deprecated in C++20. Enabled by default with -std=c++20."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a literal 0 is used as null pointer constant. This can be useful to facilitate the conversion to \"nullptr\" in C++11."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about a new-expression of a type that requires greater alignment than the alignof(std::maxalignt) but uses an allocation function without an explicit alignment parameter. This option is enabled by -Wall. Normally this only warns about global allocation functions, but -Waligned-new=all also warns about class member allocation functions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about placement new expressions with undefined behavior, such as constructing an object in a buffer that is smaller than the type of the object. For example, the placement new expression below is diagnosed because it attempts to construct an array of 64 integers in a buffer only 64 bytes large. char buf [64]; new (buf) int[64]; This warning is enabled by default. -Wplacement-new=1 This is the default warning level of -Wplacement-new. At this level the warning is not issued for some strictly undefined constructs that GCC allows as extensions for compatibility with legacy code. For example, the following \"new\" expression is not diagnosed at this level even though it has undefined behavior according to the C++ standard because it writes past the end of the one-element array. struct S { int n, a[1]; }; S *s = (S *)malloc (sizeof *s + 31 * sizeof s->a[0]); new (s->a)int [32](); -Wplacement-new=2 At this level, in addition to diagnosing all the same constructs as at level 1, a diagnostic is also issued for placement new expressions that construct an object in the last member of structure whose type is an array of a single element and whose size is less than the size of the object being constructed. While the previous example would be diagnosed, the following construct makes use of the flexible member array extension to avoid the warning at level 2. struct S { int n, a[]; }; S *s = (S *)malloc (sizeof *s + 32 * sizeof s->a[0]); new (s->a)int [32]();"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about catch handlers that do not catch via reference. With -Wcatch-value=1 (or -Wcatch-value for short) warn about polymorphic class types that are caught by value. With -Wcatch-value=2 warn about all class types that are caught by value. With -Wcatch-value=3 warn about all types that are not caught by reference. -Wcatch-value is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for conditionally-supported (C++11 [intro.defs]) constructs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn when deleting a pointer to incomplete type, which may cause undefined behavior at runtime. This warning is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about redundant semicolons after in-class function definitions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls warnings when a base class is inaccessible in a class derived from it due to ambiguity. The warning is enabled by default. Note that the warning for ambiguous virtual bases is enabled by the -Wextra option. struct A { int a; }; struct B : A { }; struct C : B, A { };"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Suppress warnings about use of C++11 inheriting constructors when the base class inherited from has a C variadic constructor; the warning is on by default because the ellipsis is not inherited."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Suppress warnings from applying the \"offsetof\" macro to a non-POD type. According to the 2014 ISO C++ standard, applying \"offsetof\" to a non-standard-layout type is undefined. In existing C++ implementations, however, \"offsetof\" typically gives meaningful results. This flag is for users who are aware that they are writing nonportable code and who have deliberately chosen to ignore the warning about it. The restrictions on \"offsetof\" may be relaxed in a future version of the C++ standard."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about a definition of an unsized deallocation function void operator delete (void *) noexcept; void operator delete[] (void *) noexcept; without a definition of the corresponding sized deallocation function void operator delete (void *, std::sizet) noexcept; void operator delete[] (void *, std::sizet) noexcept; or vice versa. Enabled by -Wextra along with -fsized-deallocation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about types with virtual methods where code quality would be improved if the type were declared with the C++11 \"final\" specifier, or, if possible, declared in an anonymous namespace. This allows GCC to more aggressively devirtualize the polymorphic calls. This warning is more effective with link-time optimization, where the information about the class hierarchy graph is more complete."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about virtual methods where code quality would be improved if the method were declared with the C++11 \"final\" specifier, or, if possible, its type were declared in an anonymous namespace or with the \"final\" specifier. This warning is more effective with link-time optimization, where the information about the class hierarchy graph is more complete. It is recommended to first consider suggestions of -Wsuggest-final-types and then rebuild with new annotations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about overriding virtual functions that are not marked with the \"override\" keyword."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about uses of pointers to dynamically allocated objects that have been rendered indeterminate by a call to a deallocation function. The warning is enabled at all optimization levels but may yield different results with optimization than without. -Wuse-after-free=1 At level 1 the warning attempts to diagnose only unconditional uses of pointers made indeterminate by a deallocation call or a successful call to \"realloc\", regardless of whether or not the call resulted in an actual reallocatio of memory. This includes double-\"free\" calls as well as uses in arithmetic and relational expressions. Although undefined, uses of indeterminate pointers in equality (or inequality) expressions are not diagnosed at this level. -Wuse-after-free=2 At level 2, in addition to unconditional uses, the warning also diagnoses conditional uses of pointers made indeterminate by a deallocation call. As at level 2, uses in equality (or inequality) expressions are not diagnosed. For example, the second call to \"free\" in the following function is diagnosed at this level: struct A { int refcount; void *data; }; void release (struct A *p) { int refcount = --p->refcount; free (p); if (refcount == 0) free (p->data); // warning: p may be used after free } -Wuse-after-free=3 At level 3, the warning also diagnoses uses of indeterminate pointers in equality expressions. All uses of indeterminate pointers are undefined but equality tests sometimes appear after calls to \"realloc\" as an attempt to determine whether the call resulted in relocating the object to a different address. They are diagnosed at a separate level to aid legacy code gradually transition to safe alternatives. For example, the equality test in the function below is diagnosed at this level: void adjustpointers (int, int); void grow (int p, int n) { int q = (int)realloc (p, n *= 2); if (q == p) return; adjustpointers ((int)q, n); } To avoid the warning at this level, store offsets into allocated memory instead of pointers. This approach obviates needing to adjust the stored pointers after reallocation. -Wuse-after-free=2 is included in -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when an expression is cast to its own type. This warning does not occur when a class object is converted to a non-reference type as that is a way to create a temporary: struct S { }; void g (S&&); void f (S&& arg) { g (S(arg)); // make arg prvalue so that it can bind to S&& }"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn for conversions between \"NULL\" and non-pointer types. -Wconversion-null is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use class-name as the name of the class to instantiate for each literal string specified with the syntax \"@\"...\"\". The default class name is \"NXConstantString\" if the GNU runtime is being used, and \"NSConstantString\" if the NeXT runtime is being used (see below). On Darwin (macOS, MacOS X) platforms, the -fconstant-cfstrings option, if also present, overrides the -fconstant-string-class setting and cause \"@\"...\"\" literals to be laid out as constant CoreFoundation strings. Note that -fconstant-cfstrings is an alias for the target-specific -mconstant-cfstrings equivalent."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate object code compatible with the standard GNU Objective-C runtime. This is the default for most types of systems."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output compatible with the NeXT runtime. This is the default for NeXT-based systems, including Darwin and Mac OS X. The macro \"NEXTRUNTIME\" is predefined if (and only if) this option is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that all Objective-C message dispatches (\"[receiver message:arg]\") in this translation unit ensure that the receiver is not \"nil\". This allows for more efficient entry points in the runtime to be used. This option is only available in conjunction with the NeXT runtime and ABI version 0 or 1."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use version n of the Objective-C ABI for the selected runtime. This option is currently supported only for the NeXT runtime. In that case, Version 0 is the traditional (32-bit) ABI without support for properties and other Objective-C 2.0 additions. Version 1 is the traditional (32-bit) ABI with support for properties and other Objective-C 2.0 additions. Version 2 is the modern (64-bit) ABI. If nothing is specified, the default is Version 0 on 32-bit target machines, and Version 2 on 64-bit target machines."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "For each Objective-C class, check if any of its instance variables is a C++ object with a non-trivial default constructor. If so, synthesize a special \"- (id) .cxxconstruct\" instance method which runs non-trivial default constructors on any such instance variables, in order, and then return \"self\". Similarly, check if any instance variable is a C++ object with a non-trivial destructor, and if so, synthesize a special \"- (void) .cxxdestruct\" method which runs all such default destructors, in reverse order. The \"- (id) .cxxconstruct\" and \"- (void) .cxxdestruct\" methods thusly generated only operate on instance variables declared in the current Objective-C class, and not those inherited from superclasses. It is the responsibility of the Objective-C runtime to invoke all such methods in an object's inheritance hierarchy. The \"- (id) .cxxconstruct\" methods are invoked by the runtime immediately after a new object instance is allocated; the \"- (void) .cxxdestruct\" methods are invoked immediately before the runtime deallocates an object instance. As of this writing, only the NeXT runtime on Mac OS X 10.4 and later has support for invoking the \"- (id) .cxxconstruct\" and \"- (void) .cxxdestruct\" methods."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow fast jumps to the message dispatcher. On Darwin this is accomplished via the comm page."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable syntactic support for structured exception handling in Objective-C, similar to what is offered by C++. This option is required to use the Objective-C keywords @try, @throw, @catch, @finally and @synchronized. This option is available with both the GNU runtime and the NeXT runtime (but not available in conjunction with the NeXT runtime on Mac OS X 10.2 and earlier)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable garbage collection (GC) in Objective-C and Objective-C++ programs. This option is only available with the NeXT runtime; the GNU runtime has a different garbage collection implementation that does not require special compiler flags."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "For the NeXT runtime with version 2 of the ABI, check for a nil receiver in method invocations before doing the actual method call. This is the default and can be disabled using -fno-objc-nilcheck. Class methods and super calls are never checked for nil in this way no matter what this flag is set to. Currently this flag does nothing when the GNU runtime, or an older version of the NeXT runtime ABI, is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Conform to the language syntax of Objective-C 1.0, the language recognized by GCC 4.0. This only affects the Objective-C additions to the C/C++ language; it does not affect conformance to C/C++ standards, which is controlled by the separate C/C++ dialect option flags. When this option is used with the Objective-C or Objective-C++ compiler, any Objective-C syntax that is not recognized by GCC 4.0 is rejected. This is useful if you need to make sure that your Objective-C code can be compiled with older versions of GCC."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit a special marker instructing ld(1) not to statically link in the resulting object file, and allow dyld(1) to load it in at run time instead. This is used in conjunction with the Fix-and-Continue debugging mode, where the object file in question may be recompiled and dynamically reloaded in the course of program execution, without the need to restart the program itself. Currently, Fix-and-Continue functionality is only available in conjunction with the NeXT runtime on Mac OS X 10.3 and later."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When compiling for the NeXT runtime, the compiler ordinarily replaces calls to objcgetClass(\"...\") (when the name of the class is known at compile time) with static class references that get initialized at load time, which improves run-time performance. Specifying the -fzero-link flag suppresses this behavior and causes calls to objcgetClass(\"...\") to be retained. This is useful in Zero-Link debugging mode, since it allows for individual class implementations to be modified during program execution. The GNU runtime currently always retains calls to objcgetclass(\"...\") regardless of command-line options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "By default instance variables in Objective-C can be accessed as if they were local variables from within the methods of the class they're declared in. This can lead to shadowing between instance variables and other variables declared either locally inside a class method or globally with the same name. Specifying the -fno-local-ivars flag disables this behavior thus avoiding variable shadowing issues."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the default instance variable visibility to the specified option so that instance variables declared outside the scope of any access modifier directives default to the specified visibility."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dump interface declarations for all classes seen in the source file to a file named sourcename.decl."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever an Objective-C assignment is being intercepted by the garbage collector."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn if a property for an Objective-C object has no assign semantics specified."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If a class is declared to implement a protocol, a warning is issued for every method in the protocol that is not implemented by the class. The default behavior is to issue a warning for every method not explicitly implemented in the class, even if a method implementation is inherited from the superclass. If you use the -Wno-protocol option, then methods inherited from the superclass are considered to be implemented, and no warning is issued for them."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a class interface lacks a superclass. Most classes will inherit from \"NSObject\" (or \"Object\") for example. When declaring classes intended to be root classes, the warning can be suppressed by marking their interfaces with \"attribute((objcrootclass))\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if multiple methods of different types for the same selector are found during compilation. The check is performed on the list of methods in the final stage of compilation. Additionally, a check is performed for each selector appearing in a @selector(...) expression, and a corresponding method for that selector has been found during compilation. Because these checks scan the method table only at the end of compilation, these warnings are not produced if the final stage of compilation is not reached, for example because an error is found during compilation, or because the -fsyntax-only option is being used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if multiple methods with differing argument and/or return types are found for a given selector when attempting to send a message using this selector to a receiver of type \"id\" or \"Class\". When this flag is off (which is the default behavior), the compiler omits such warnings if any differences found are confined to types that share the same size and alignment."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a @selector(...) expression referring to an undeclared selector is found. A selector is considered undeclared if no method with that name has been declared before the @selector(...) expression, either explicitly in an @interface or @protocol declaration, or implicitly in an @implementation section. This option always performs its checks as soon as a @selector(...) expression is found, while -Wselector only performs its checks in the final stage of compilation. This also enforces the coding style convention that methods and selectors must be declared before being used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate C header describing the largest structure that is passed by value, if any."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Try to format error messages so that they fit on lines of about n characters. If n is zero, then no line-wrapping is done; each error message appears on a single line. This is the default for all front ends. Note - this option also affects the display of the #error and #warning pre-processor directives, and the deprecated function/type/variable attribute. It does not however affect the pragma GCC warning and pragma GCC error pragmas."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option requests that diagnostic output look as plain as possible, which may be useful when running dejagnu or other utilities that need to parse diagnostics output and prefer that it remain more stable over time. -fdiagnostics-plain-output is currently equivalent to the following options: -fno-diagnostics-show-caret -fno-diagnostics-show-line-numbers -fdiagnostics-color=never -fdiagnostics-urls=never -fdiagnostics-path-format=separate-events In the future, if GCC changes the default appearance of its diagnostics, the corresponding option to disable the new behavior will be added to this list."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Only meaningful in line-wrapping mode. Instructs the diagnostic messages reporter to emit source location information once; that is, in case the message is too long to fit on a single physical line and has to be wrapped, the source location won't be emitted (as prefix) again, over and over, in subsequent continuation lines. This is the default behavior."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Only meaningful in line-wrapping mode. Instructs the diagnostic messages reporter to emit the same source location information (as prefix) for physical lines that result from the process of breaking a message which is too long to fit on a single line."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use color in diagnostics. WHEN is never, always, or auto. The default depends on how the compiler has been configured, it can be any of the above WHEN options or also never if GCCCOLORS environment variable isn't present in the environment, and auto otherwise. auto makes GCC use color only when the standard error is a terminal, and when not executing in an emacs shell. The forms -fdiagnostics-color and -fno-diagnostics-color are aliases for -fdiagnostics-color=always and -fdiagnostics-color=never, respectively. The colors are defined by the environment variable GCCCOLORS. Its value is a colon- separated list of capabilities and Select Graphic Rendition (SGR) substrings. SGR commands are interpreted by the terminal or terminal emulator. (See the section in the documentation of your text terminal for permitted values and their meanings as character attributes.) These substring values are integers in decimal representation and can be concatenated with semicolons. Common values to concatenate include 1 for bold, 4 for underline, 5 for blink, 7 for inverse, 39 for default foreground color, 30 to 37 for foreground colors, 90 to 97 for 16-color mode foreground colors, 38;5;0 to 38;5;255 for 88-color and 256-color modes foreground colors, 49 for default background color, 40 to 47 for background colors, 100 to 107 for 16-color mode background colors, and 48;5;0 to 48;5;255 for 88-color and 256-color modes background colors. The default GCCCOLORS is error=01;31:warning=01;35:note=01;36:range1=32:range2=34:locus=01:\\ quote=01:path=01;36:fixit-insert=32:fixit-delete=31:\\ diff-filename=01:diff-hunk=32:diff-delete=31:diff-insert=32:\\ type-diff=01;32:fnname=01;32:targs=35 where 01;31 is bold red, 01;35 is bold magenta, 01;36 is bold cyan, 32 is green, 34 is blue, 01 is bold, and 31 is red. Setting GCCCOLORS to the empty string disables colors. Supported capabilities are as follows. \"error=\" SGR substring for error: markers. \"warning=\" SGR substring for warning: markers. \"note=\" SGR substring for note: markers. \"path=\" SGR substring for colorizing paths of control-flow events as printed via -fdiagnostics-path-format=, such as the identifiers of individual events and lines indicating interprocedural calls and returns. \"range1=\" SGR substring for first additional range. \"range2=\" SGR substring for second additional range. \"locus=\" SGR substring for location information, file:line or file:line:column etc. \"quote=\" SGR substring for information printed within quotes. \"fnname=\" SGR substring for names of C++ functions. \"targs=\" SGR substring for C++ function template parameter bindings. \"fixit-insert=\" SGR substring for fix-it hints suggesting text to be inserted or replaced. \"fixit-delete=\" SGR substring for fix-it hints suggesting text to be deleted. \"diff-filename=\" SGR substring for filename headers within generated patches. \"diff-hunk=\" SGR substring for the starts of hunks within generated patches. \"diff-delete=\" SGR substring for deleted lines within generated patches. \"diff-insert=\" SGR substring for inserted lines within generated patches. \"type-diff=\" SGR substring for highlighting mismatching types within template arguments in the C++ frontend."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use escape sequences to embed URLs in diagnostics. For example, when -fdiagnostics-show-option emits text showing the command-line option controlling a diagnostic, embed a URL for documentation of that option. WHEN is never, always, or auto. auto makes GCC use URL escape sequences only when the standard error is a terminal, and when not executing in an emacs shell or any graphical terminal which is known to be incompatible with this feature, see below. The default depends on how the compiler has been configured. It can be any of the above WHEN options. GCC can also be configured (via the --with-diagnostics-urls=auto-if-env configure-time option) so that the default is affected by environment variables. Under such a configuration, GCC defaults to using auto if either GCCURLS or TERMURLS environment variables are present and non-empty in the environment of the compiler, or never if neither are. However, even with -fdiagnostics-urls=always the behavior is dependent on those environment variables: If GCCURLS is set to empty or no, do not embed URLs in diagnostics. If set to st, URLs use ST escape sequences. If set to bel, the default, URLs use BEL escape sequences. Any other non-empty value enables the feature. If GCCURLS is not set, use TERMURLS as a fallback. Note: ST is an ANSI escape sequence, string terminator ESC \\, BEL is an ASCII character, CTRL-G that usually sounds like a beep. At this time GCC tries to detect also a few terminals that are known to not implement the URL feature, and have bugs or at least had bugs in some versions that are still in use, where the URL escapes are likely to misbehave, i.e. print garbage on the screen. That list is currently xfce4-terminal, certain known to be buggy gnome-terminal versions, the linux console, and mingw. This check can be skipped with the -fdiagnostics-urls=always."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "By default, each diagnostic emitted includes text indicating the command-line option that directly controls the diagnostic (if such an option is known to the diagnostic machinery). Specifying the -fno-diagnostics-show-option flag suppresses that behavior."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "By default, each diagnostic emitted includes the original source line and a caret ^ indicating the column. This option suppresses this information. The source line is truncated to n characters, if the -fmessage-length=n option is given. When the output is done to the terminal, the width is limited to the width given by the COLUMNS environment variable or, if not set, to the terminal width."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "By default, when printing source code (via -fdiagnostics-show-caret), diagnostics can label ranges of source code with pertinent information, such as the types of expressions: printf (\"foo %s bar\", longi + longj); ~^ ~~~~~~~~~~~~~~~ | | char * long int This option suppresses the printing of these labels (in the example above, the vertical bars and the \"char *\" and \"long int\" text)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Diagnostic messages can optionally have an associated CWE (\"https://cwe.mitre.org/index.html\") identifier. GCC itself only provides such metadata for some of the -fanalyzer diagnostics. GCC plugins may also provide diagnostics with such metadata. By default, if this information is present, it will be printed with the diagnostic. This option suppresses the printing of this metadata."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Diagnostic messages can optionally have rules associated with them, such as from a coding standard, or a specification. GCC itself does not do this for any of its diagnostics, but plugins may do so. By default, if this information is present, it will be printed with the diagnostic. This option suppresses the printing of this metadata."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "By default, when printing source code (via -fdiagnostics-show-caret), a left margin is printed, showing line numbers. This option suppresses this left margin."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls the minimum width of the left margin printed by -fdiagnostics-show-line-numbers. It defaults to 6."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit fix-it hints in a machine-parseable format, suitable for consumption by IDEs. For each fix-it, a line will be printed after the relevant diagnostic, starting with the string \"fix-it:\". For example: fix-it:\"test.c\":{45:3-45:21}:\"gtkwidgetshowall\" The location is expressed as a half-open range, expressed as a count of bytes, starting at byte 1 for the initial column. In the above example, bytes 3 through 20 of line 45 of \"test.c\" are to be replaced with the given string: 00000000011111111112222222222 12345678901234567890123456789 gtkwidgetshowall (dlg); ^^^^^^^^^^^^^^^^^^ gtkwidgetshowall The filename and replacement string escape backslash as \"\\\\\", tab as \"\\t\", newline as \"\\n\", double quotes as \"\\\"\", non-printable characters as octal (e.g. vertical tab as \"\\013\"). An empty replacement string indicates that the given range is to be removed. An empty range (e.g. \"45:3-45:3\") indicates that the string is to be inserted at the given position."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print fix-it hints to stderr in unified diff format, after any diagnostics are printed. For example: --- test.c +++ test.c @ -42,5 +42,5 @ void showcb(GtkDialog *dlg) { - gtkwidgetshowall(dlg); + gtkwidgetshowall(dlg); } The diff may or may not be colorized, following the same rules as for diagnostics (see -fdiagnostics-color)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "In the C++ frontend, when printing diagnostics showing mismatching template types, such as: could not convert 'std::map<int, std::vector<double> >()' from 'map<[...],vector<double>>' to 'map<[...],vector<float>> the -fdiagnostics-show-template-tree flag enables printing a tree-like structure showing the common and differing parts of the types, such as: map< [...], vector< [double != float]>> The parts that differ are highlighted with color (\"double\" and \"float\" in this case)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "By default when the C++ frontend prints diagnostics showing mismatching template types, common parts of the types are printed as \"[...]\" to simplify the error message. For example: could not convert 'std::map<int, std::vector<double> >()' from 'map<[...],vector<double>>' to 'map<[...],vector<float>> Specifying the -fno-elide-type flag suppresses that behavior. This flag also affects the output of the -fdiagnostics-show-template-tree flag."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify how to print paths of control-flow events for diagnostics that have such a path associated with them. KIND is none, separate-events, or inline-events, the default. none means to not print diagnostic paths. separate-events means to print a separate \"note\" diagnostic for each event within the diagnostic. For example: test.c:29:5: error: passing NULL as argument 1 to 'PyListAppend' which requires a non-NULL parameter test.c:25:10: note: (1) when 'PyListNew' fails, returning NULL test.c:27:3: note: (2) when 'i < count' test.c:29:5: note: (3) when calling 'PyListAppend', passing NULL from (1) as argument 1 inline-events means to print the events \"inline\" within the source code. This view attempts to consolidate the events into runs of sufficiently-close events, printing them as labelled ranges within the source. For example, the same events as above might be printed as: 'test': events 1-3 | | 25 | list = PyListNew(0); | | ^~~~~~~~~~~~~ | | | | | (1) when 'PyListNew' fails, returning NULL | 26 | | 27 | for (i = 0; i < count; i++) { | | ~~~ | | | | | (2) when 'i < count' | 28 | item = PyLongFromLong(random()); | 29 | PyListAppend(list, item); | | ~~~~~~~~~~~~~~~~~~~~~~~~~ | | | | | (3) when calling 'PyListAppend', passing NULL from (1) as argument 1 | Interprocedural control flow is shown by grouping the events by stack frame, and using indentation to show how stack frames are nested, pushed, and popped. For example: 'test': events 1-2 | | 133 | { | | ^ | | | | | (1) entering 'test' | 134 | boxedint *obj = makeboxedint (i); | | ~~~~~~~~~~~~~~~~~~ | | | | | (2) calling 'makeboxedint' | +--> 'makeboxedint': events 3-4 | | 120 | { | | ^ | | | | | (3) entering 'makeboxedint' | 121 | boxedint *result = (boxedint *)wrappedmalloc (sizeof (boxedint)); | | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | | | | | (4) calling 'wrappedmalloc' | +--> 'wrappedmalloc': events 5-6 | | 7 | { | | ^ | | | | | (5) entering 'wrappedmalloc' | 8 | return malloc (size); | | ~~~~~~~~~~~~~ | | | | | (6) calling 'malloc' | <-------------+ | 'test': event 7 | | 138 | freeboxedint (obj); | | ^~~~~~~~~~~~~~~~~~~~ | | | | | (7) calling 'freeboxedint' | (etc)"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option provides additional information when printing control-flow paths associated with a diagnostic. If this is option is provided then the stack depth will be printed for each run of events within -fdiagnostics-path-format=inline-events. If provided with -fdiagnostics-path-format=separate-events, then the stack depth and function declaration will be appended when printing each event. This is intended for use by GCC developers and plugin developers when debugging diagnostics that report interprocedural control flow."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not print column numbers in diagnostics. This may be necessary if diagnostics are being scanned by a program that does not understand the column numbers, such as dejagnu."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select the units for the column number. This affects traditional diagnostics (in the absence of -fno-show-column), as well as JSON format diagnostics if requested. The default UNIT, display, considers the number of display columns occupied by each character. This may be larger than the number of bytes required to encode the character, in the case of tab characters, or it may be smaller, in the case of multibyte characters. For example, the character \"GREEK SMALL LETTER PI (U+03C0)\" occupies one display column, and its UTF-8 encoding requires two bytes; the character \"SLIGHTLY SMILING FACE (U+1F642)\" occupies two display columns, and its UTF-8 encoding requires four bytes. Setting UNIT to byte changes the column number to the raw byte count in all cases, as was traditionally output by GCC prior to version 11.1.0."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select the origin for column numbers, i.e. the column number assigned to the first column. The default value of 1 corresponds to traditional GCC behavior and to the GNU style guide. Some utilities may perform better with an origin of 0; any non-negative value may be specified."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When GCC prints pertinent source lines for a diagnostic it normally attempts to print the source bytes directly. However, some diagnostics relate to encoding issues in the source file, such as malformed UTF-8, or issues with Unicode normalization. These diagnostics are flagged so that GCC will escape bytes that are not printable ASCII when printing their pertinent source lines. This option controls how such bytes should be escaped. The default FORMAT, unicode displays Unicode characters that are not printable ASCII in the form <U+XXXX>, and bytes that do not correspond to a Unicode character validly- encoded in UTF-8-encoded will be displayed as hexadecimal in the form <XX>. For example, a source line containing the string before followed by the Unicode character U+03C0 (\"GREEK SMALL LETTER PI\", with UTF-8 encoding 0xCF 0x80) followed by the byte 0xBF (a stray UTF-8 trailing byte), followed by the string after will be printed for such a diagnostic as: before<U+03C0><BF>after Setting FORMAT to bytes will display all non-printable-ASCII bytes in the form <XX>, thus showing the underlying encoding of non-ASCII Unicode characters. For the example above, the following will be printed: before<CF><80><BF>after"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select a different format for printing diagnostics. FORMAT is text, sarif-stderr, sarif- file, json, json-stderr, or json-file. The default is text. The sarif-stderr and sarif-file formats both emit diagnostics in SARIF Version 2.1.0 format, either to stderr, or to a file named source.sarif, respectively. The json format is a synonym for json-stderr. The json-stderr and json-file formats are identical, apart from where the JSON is emitted to - with the former, the JSON is emitted to stderr, whereas with json-file it is written to source.gcc.json. The emitted JSON consists of a top-level JSON array containing JSON objects representing the diagnostics. The JSON is emitted as one line, without formatting; the examples below have been formatted for clarity. Diagnostics can have child diagnostics. For example, this error and note: misleading-indentation.c:15:3: warning: this 'if' clause does not guard... [-Wmisleading-indentation] 15 | if (flag) | ^~ misleading-indentation.c:17:5: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if' 17 | y = 2; | ^ might be printed in JSON form (after formatting) like this: [ { \"kind\": \"warning\", \"locations\": [ { \"caret\": { \"display-column\": 3, \"byte-column\": 3, \"column\": 3, \"file\": \"misleading-indentation.c\", \"line\": 15 }, \"finish\": { \"display-column\": 4, \"byte-column\": 4, \"column\": 4, \"file\": \"misleading-indentation.c\", \"line\": 15 } } ], \"message\": \"this \\u2018if\\u2019 clause does not guard...\", \"option\": \"-Wmisleading-indentation\", \"optionurl\": \"https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#index-Wmisleading-indentation\", \"children\": [ { \"kind\": \"note\", \"locations\": [ { \"caret\": { \"display-column\": 5, \"byte-column\": 5, \"column\": 5, \"file\": \"misleading-indentation.c\", \"line\": 17 } } ], \"escape-source\": false, \"message\": \"...this statement, but the latter is ...\" } ] \"escape-source\": false, \"column-origin\": 1, } ] where the \"note\" is a child of the \"warning\". A diagnostic has a \"kind\". If this is \"warning\", then there is an \"option\" key describing the command-line option controlling the warning. A diagnostic can contain zero or more locations. Each location has an optional \"label\" string and up to three positions within it: a \"caret\" position and optional \"start\" and \"finish\" positions. A position is described by a \"file\" name, a \"line\" number, and three numbers indicating a column position: * \"display-column\" counts display columns, accounting for tabs and multibyte characters. * \"byte-column\" counts raw bytes. * \"column\" is equal to one of the previous two, as dictated by the -fdiagnostics-column-unit option. All three columns are relative to the origin specified by -fdiagnostics-column-origin, which is typically equal to 1 but may be set, for instance, to 0 for compatibility with other utilities that number columns from 0. The column origin is recorded in the JSON output in the \"column-origin\" tag. In the remaining examples below, the extra column number outputs have been omitted for brevity. For example, this error: bad-binary-ops.c:64:23: error: invalid operands to binary + (have 'S' {aka 'struct s'} and 'T' {aka 'struct t'}) 64 | return callee4a () + callee4b (); | ~~~~~~~~~~~~ ^ ~~~~~~~~~~~~ | | | | | T {aka struct t} | S {aka struct s} has three locations. Its primary location is at the \"+\" token at column 23. It has two secondary locations, describing the left and right-hand sides of the expression, which have labels. It might be printed in JSON form as: { \"children\": [], \"kind\": \"error\", \"locations\": [ { \"caret\": { \"column\": 23, \"file\": \"bad-binary-ops.c\", \"line\": 64 } }, { \"caret\": { \"column\": 10, \"file\": \"bad-binary-ops.c\", \"line\": 64 }, \"finish\": { \"column\": 21, \"file\": \"bad-binary-ops.c\", \"line\": 64 }, \"label\": \"S {aka struct s}\" }, { \"caret\": { \"column\": 25, \"file\": \"bad-binary-ops.c\", \"line\": 64 }, \"finish\": { \"column\": 36, \"file\": \"bad-binary-ops.c\", \"line\": 64 }, \"label\": \"T {aka struct t}\" } ], \"escape-source\": false, \"message\": \"invalid operands to binary + ...\" } If a diagnostic contains fix-it hints, it has a \"fixits\" array, consisting of half-open intervals, similar to the output of -fdiagnostics-parseable-fixits. For example, this diagnostic with a replacement fix-it hint: demo.c:8:15: error: 'struct s' has no member named 'colour'; did you mean 'color'? 8 | return ptr->colour; | ^~~~~~ | color might be printed in JSON form as: { \"children\": [], \"fixits\": [ { \"next\": { \"column\": 21, \"file\": \"demo.c\", \"line\": 8 }, \"start\": { \"column\": 15, \"file\": \"demo.c\", \"line\": 8 }, \"string\": \"color\" } ], \"kind\": \"error\", \"locations\": [ { \"caret\": { \"column\": 15, \"file\": \"demo.c\", \"line\": 8 }, \"finish\": { \"column\": 20, \"file\": \"demo.c\", \"line\": 8 } } ], \"escape-source\": false, \"message\": \"\\u2018struct s\\u2019 has no member named ...\" } where the fix-it hint suggests replacing the text from \"start\" up to but not including \"next\" with \"string\"'s value. Deletions are expressed via an empty value for \"string\", insertions by having \"start\" equal \"next\". If the diagnostic has a path of control-flow events associated with it, it has a \"path\" array of objects representing the events. Each event object has a \"description\" string, a \"location\" object, along with a \"function\" string and a \"depth\" number for representing interprocedural paths. The \"function\" represents the current function at that event, and the \"depth\" represents the stack depth relative to some baseline: the higher, the more frames are within the stack. For example, the intraprocedural example shown for -fdiagnostics-path-format= might have this JSON for its path: \"path\": [ { \"depth\": 0, \"description\": \"when 'PyListNew' fails, returning NULL\", \"function\": \"test\", \"location\": { \"column\": 10, \"file\": \"test.c\", \"line\": 25 } }, { \"depth\": 0, \"description\": \"when 'i < count'\", \"function\": \"test\", \"location\": { \"column\": 3, \"file\": \"test.c\", \"line\": 27 } }, { \"depth\": 0, \"description\": \"when calling 'PyListAppend', passing NULL from (1) as argument 1\", \"function\": \"test\", \"location\": { \"column\": 5, \"file\": \"test.c\", \"line\": 29 } } ] Diagnostics have a boolean attribute \"escape-source\", hinting whether non-ASCII bytes should be escaped when printing the pertinent lines of source code (\"true\" for diagnostics involving source encoding issues)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Check the code for syntax errors, but don't do anything beyond that."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Limits the maximum number of error messages to n, at which point GCC bails out rather than attempting to continue processing the source code. If n is 0 (the default), there is no limit on the number of error messages produced. If -Wfatal-errors is also specified, then -Wfatal-errors takes precedence over this option."
        },
        {
            "flag": "-w",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Make all warnings into errors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Make the specified warning into an error. The specifier for a warning is appended; for example -Werror=switch turns the warnings controlled by -Wswitch into errors. This switch takes a negative form, to be used to negate -Werror for specific warnings; for example -Wno-error=switch makes -Wswitch warnings not be errors, even when -Werror is in effect. The warning message for each controllable warning includes the option that controls the warning. That option can then be used with -Werror= and -Wno-error= as described above. (Printing of the option in the warning message can be disabled using the -fno-diagnostics-show-option flag.) Note that specifying -Werror=foo automatically implies -Wfoo. However, -Wno-error=foo does not imply anything."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option causes the compiler to abort compilation on the first error occurred rather than trying to keep going and printing further error messages. You can request many specific warnings with options beginning with -W, for example -Wimplicit to request warnings on implicit declarations. Each of these specific warning options also has a negative form beginning -Wno- to turn off warnings; for example, -Wno-implicit. This manual lists only one of the two forms, whichever is not the default. For further language- specific options also refer to C++ Dialect Options and Objective-C and Objective-C++ Dialect Options. Additional warnings can be produced by enabling the static analyzer; Some options, such as -Wall and -Wextra, turn on other options, such as -Wunused, which may turn on further options, such as -Wunused-value. The combined effect of positive and negative forms is that more specific options have priority over less specific ones, independently of their position in the command-line. For options of the same specificity, the last one takes effect. Options enabled or disabled via pragmas take effect as if they appeared at the end of the command-line. When an unrecognized warning option is requested (e.g., -Wunknown-warning), GCC emits a diagnostic stating that the option is not recognized. However, if the -Wno- form is used, the behavior is slightly different: no diagnostic is produced for -Wno-unknown-warning unless other diagnostics are being produced. This allows the use of new -Wno- options with old compilers, but if something goes wrong, the compiler warns that an unrecognized option is present. The effectiveness of some warnings depends on optimizations also being enabled. For example"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "other warnings may not be issued at all unless optimization is enabled. While optimization in general improves the efficacy of control and data flow sensitive warnings, in some cases it may also cause false positives."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Issue all the warnings demanded by strict ISO C and ISO C++; reject all programs that use forbidden extensions, and some other programs that do not follow ISO C and ISO C++. For ISO C, follows the version of the ISO C standard specified by any -std option used. Valid ISO C and ISO C++ programs should compile properly with or without this option (though a rare few require -ansi or a -std option specifying the required version of ISO C). However, without this option, certain GNU extensions and traditional C and C++ features are supported as well. With this option, they are rejected. -Wpedantic does not cause warning messages for use of the alternate keywords whose names begin and end with . This alternate format can also be used to disable warnings for non-ISO intN types, i.e. intN. Pedantic warnings are also disabled in the expression that follows \"extension\". However, only system header files should use these escape routes; application programs should avoid them. Some users try to use -Wpedantic to check programs for strict ISO C conformance. They soon find that it does not do quite what they want: it finds some non-ISO practices, but not all---only those for which ISO C requires a diagnostic, and some others for which diagnostics have been added. A feature to report any failure to conform to ISO C might be useful in some instances, but would require considerable additional work and would be quite different from -Wpedantic. We don't have plans to support such a feature in the near future. Where the standard specified with -std represents a GNU extended dialect of C, such as gnu90 or gnu99, there is a corresponding base standard, the version of ISO C on which the GNU extended dialect is based. Warnings from -Wpedantic are given where they are required by the base standard. (It does not make sense for such warnings to be given only for features not in the specified GNU C dialect, since by definition the GNU dialects of C include all features the compiler supports with the given option, and there would be nothing to warn about.)"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Give an error whenever the base standard (see -Wpedantic) requires a diagnostic, in some cases where there is undefined behavior at compile-time and in some other cases that do not prevent compilation of programs that are valid according to the standard. This is not equivalent to -Werror=pedantic, since there are errors enabled by this option and not enabled by the latter and vice versa."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This enables all the warnings about constructions that some users consider questionable, and that are easy to avoid (or modify to prevent the warning), even in conjunction with macros. This also enables some language-specific warnings described in C++ Dialect Options and Objective-C and Objective-C++ Dialect Options. -Wall turns on the following warning flags: -Waddress -Warray-bounds=1 (only with -O2) -Warray-compare -Warray-parameter=2 (C and Objective-C only) -Wbool-compare -Wbool-operation -Wc++11-compat -Wc++14-compat -Wcatch-value (C++ and Objective-C++ only) -Wchar-subscripts -Wcomment -Wdangling-pointer=2 -Wduplicate-decl-specifier (C and Objective-C only) -Wenum-compare (in C/ObjC; this is on by default in C++) -Wenum-int-mismatch (C and Objective-C only) -Wformat -Wformat-overflow -Wformat-truncation -Wint-in-bool-context -Wimplicit (C and Objective-C only) -Wimplicit-int (C and Objective-C only) -Wimplicit-function-declaration (C and Objective-C only) -Winit-self (only for C++) -Wlogical-not-parentheses -Wmain (only for C/ObjC and unless -ffreestanding) -Wmaybe-uninitialized -Wmemset-elt-size -Wmemset-transposed-args -Wmisleading-indentation (only for C/C++) -Wmismatched-dealloc -Wmismatched-new-delete (only for C/C++) -Wmissing-attributes -Wmissing-braces (only for C/ObjC) -Wmultistatement-macros -Wnarrowing (only for C++) -Wnonnull -Wnonnull-compare -Wopenmp-simd -Wparentheses -Wpessimizing-move (only for C++) -Wpointer-sign -Wrange-loop-construct (only for C++) -Wreorder -Wrestrict -Wreturn-type -Wself-move (only for C++) -Wsequence-point -Wsign-compare (only in C++) -Wsizeof-array-div -Wsizeof-pointer-div -Wsizeof-pointer-memaccess -Wstrict-aliasing -Wstrict-overflow=1 -Wswitch -Wtautological-compare -Wtrigraphs -Wuninitialized -Wunknown-pragmas -Wunused-function -Wunused-label -Wunused-value -Wunused-variable -Wuse-after-free=2 -Wvla-parameter (C and Objective-C only) -Wvolatile-register-var -Wzero-length-bounds Note that some warning flags are not implied by -Wall. Some of them warn about constructions that users generally do not consider questionable, but which occasionally you might wish to check for; others warn about constructions that are necessary or hard to avoid in some cases, and there is no simple way to modify the code to suppress the warning. Some of them are enabled by -Wextra but many of them must be enabled individually."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This enables some extra warning flags that are not enabled by -Wall. (This option used to be called -W. The older name is still supported, but the newer name is more descriptive.) -Wclobbered -Wcast-function-type -Wdangling-reference (C++ only) -Wdeprecated-copy (C++ only) -Wempty-body -Wenum-conversion (C only) -Wignored-qualifiers -Wimplicit-fallthrough=3 -Wmissing-field-initializers -Wmissing-parameter-type (C only) -Wold-style-declaration (C only) -Woverride-init -Wsign-compare (C only) -Wstring-compare -Wredundant-move (only for C++) -Wtype-limits -Wuninitialized -Wshift-negative-value (in C++11 to C++17 and in C99 and newer) -Wunused-parameter (only with -Wunused or -Wall) -Wunused-but-set-parameter (only with -Wunused or -Wall) The option -Wextra also prints warning messages for the following cases: * A pointer is compared against integer zero with \"<\", \"<=\", \">\", or \">=\". * (C++ only) An enumerator and a non-enumerator both appear in a conditional expression. * (C++ only) Ambiguous virtual bases. * (C++ only) Subscripting an array that has been declared \"register\". * (C++ only) Taking the address of a variable that has been declared \"register\". * (C++ only) A base class is not initialized in the copy constructor of a derived class."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about code affected by ABI changes. This includes code that may not be compatible with the vendor-neutral C++ ABI as well as the psABI for the particular target. Since G++ now defaults to updating the ABI with each major release, normally -Wabi warns only about C++ ABI compatibility problems if there is a check added later in a release series for an ABI issue discovered since the initial release. -Wabi warns about more things if an older ABI version is selected (with -fabi-version=n). -Wabi can also be used with an explicit version number to warn about C++ ABI compatibility with a particular -fabi-version level, e.g. -Wabi=2 to warn about changes relative to -fabi-version=2. If an explicit version number is provided and -fabi-compat-version is not specified, the version number from this option is used for compatibility aliases. If no explicit version number is provided with this option, but -fabi-compat-version is specified, that version number is used for C++ ABI warnings. Although an effort has been made to warn about all such cases, there are probably some cases that are not warned about, even though G++ is generating incompatible code. There may also be cases where warnings are emitted even though the code that is generated is compatible. You should rewrite your code to avoid these warnings if you are concerned about the fact that code generated by G++ may not be binary compatible with code generated by other compilers. Known incompatibilities in -fabi-version=2 (which was the default from GCC 3.4 to 4.9) include: * A template with a non-type template parameter of reference type was mangled incorrectly: extern int N; template <int &> struct S {}; void n (S<N>) {2} This was fixed in -fabi-version=3. * SIMD vector types declared using \"attribute ((vectorsize))\" were mangled in a non- standard way that does not allow for overloading of functions taking vectors of different sizes. The mangling was changed in -fabi-version=4. * \"attribute ((const))\" and \"noreturn\" were mangled as type qualifiers, and \"decltype\" of a plain declaration was folded away. These mangling issues were fixed in -fabi-version=5. * Scoped enumerators passed as arguments to a variadic function are promoted like unscoped enumerators, causing \"vaarg\" to complain. On most targets this does not actually affect the parameter passing ABI, as there is no way to pass an argument smaller than \"int\". Also, the ABI changed the mangling of template argument packs, \"constcast\", \"staticcast\", prefix increment/decrement, and a class scope function used as a template argument. These issues were corrected in -fabi-version=6. * Lambdas in default argument scope were mangled incorrectly, and the ABI changed the mangling of \"nullptrt\". These issues were corrected in -fabi-version=7. * When mangling a function type with function-cv-qualifiers, the un-qualified function type was incorrectly treated as a substitution candidate. This was fixed in -fabi-version=8, the default for GCC 5.1. * decltype(nullptr) incorrectly had an alignment of 1, leading to unaligned accesses. Note that this did not affect the ABI of a function with a \"nullptrt\" parameter, as parameters have a minimum alignment. This was fixed in -fabi-version=9, the default for GCC 5.2. * Target-specific attributes that affect the identity of a type, such as ia32 calling conventions on a function type (stdcall, regparm, etc.), did not affect the mangled name, leading to name collisions when function pointers were used as template arguments. This was fixed in -fabi-version=10, the default for GCC 6.1. This option also enables warnings about psABI-related changes. The known psABI changes at this point include: * For SysV/x86-64, unions with \"long double\" members are passed in memory as specified in psABI. Prior to GCC 4.4, this was not the case. For example: union U { long double ld; int i; }; \"union U\" is now always passed in memory."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "C++ requires that unqualified uses of a name within a class have the same meaning in the complete scope of the class, so declaring the name after using it is ill-formed: struct A; struct B1 { A a; typedef A A; }; // warning, 'A' changes meaning struct B2 { A a; struct A { }; }; // error, 'A' changes meaning By default, the B1 case is only a warning because the two declarations have the same type, while the B2 case is an error. Both diagnostics can be disabled with -Wno-changes-meaning. Alternately, the error case can be reduced to a warning with -Wno-error=changes-meaning or -fpermissive. Both diagnostics are also suppressed by -fms-extensions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if an array subscript has type \"char\". This is a common cause of error, as programmers often forget that this type is signed on some machines. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if feedback profiles do not match when using the -fprofile-use option. If a source file is changed between compiling with -fprofile-generate and with -fprofile-use, the files with the profile feedback can fail to match the source file and GCC cannot use the profile feedback information. By default, this warning is enabled and is treated as an error. -Wno-coverage-mismatch can be used to disable the warning or -Wno-error=coverage-mismatch can be used to disable the error. Disabling the error for this warning can result in poorly optimized code and is useful only in the case of very minor changes such as bug fixes to an existing code-base. Completely disabling the warning is not recommended."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn in case a function ends earlier than it begins due to an invalid linenum macros. The warning is emitted only with --coverage enabled. By default, this warning is enabled and is treated as an error. -Wno-coverage-invalid-line-number can be used to disable the warning or -Wno-error=coverage-invalid-line-number can be used to disable the error."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Suppress warning messages emitted by \"#warning\" directives."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Give a warning when a value of type \"float\" is implicitly promoted to \"double\". CPUs with a 32-bit \"single-precision\" floating-point unit implement \"float\" in hardware, but emulate \"double\" in software. On such a machine, doing computations using \"double\" values is much more expensive because of the overhead required for software emulation. It is easy to accidentally do computations with \"double\" because floating-point literals are implicitly of type \"double\". For example, in: float area(float radius) { return 3.14159 * radius * radius; } the compiler performs the entire computation with \"double\" because the floating-point literal is a \"double\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a declaration has duplicate \"const\", \"volatile\", \"restrict\" or \"Atomic\" specifier. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Check calls to \"printf\" and \"scanf\", etc., to make sure that the arguments supplied have types appropriate to the format string specified, and that the conversions specified in the format string make sense. This includes standard functions, and others specified by format attributes, in the \"printf\", \"scanf\", \"strftime\" and \"strfmon\" (an X/Open extension, not in the C standard) families (or other target-specific families). Which functions are checked without format attributes having been specified depends on the standard version selected, and such checks of functions without the attribute specified are disabled by -ffreestanding or -fno-builtin. The formats are checked against the format features supported by GNU libc version 2.2. These include all ISO C90 and C99 features, as well as features from the Single Unix Specification and some BSD and GNU extensions. Other library implementations may not support all these features; GCC does not support warning about features that go beyond a particular library's limitations. However, if -Wpedantic is used with -Wformat, warnings are given about format features not in the selected standard version (but not for \"strfmon\" formats, since those are not in any version of the C standard). -Wformat=1 -Wformat Option -Wformat is equivalent to -Wformat=1, and -Wno-format is equivalent to -Wformat=0. Since -Wformat also checks for null format arguments for several functions, -Wformat also implies -Wnonnull. Some aspects of this level of format checking can be disabled by the options: -Wno-format-contains-nul, -Wno-format-extra-args, and -Wno-format-zero-length. -Wformat is enabled by -Wall. -Wformat=2 Enable -Wformat plus additional format checks. Currently equivalent to -Wformat -Wformat-nonliteral -Wformat-security -Wformat-y2k."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If -Wformat is specified, do not warn about format strings that contain NUL bytes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If -Wformat is specified, do not warn about excess arguments to a \"printf\" or \"scanf\" format function. The C standard specifies that such arguments are ignored. Where the unused arguments lie between used arguments that are specified with $ operand number specifications, normally warnings are still given, since the implementation could not know what type to pass to \"vaarg\" to skip the unused arguments. However, in the case of \"scanf\" formats, this option suppresses the warning if the unused arguments are all pointers, since the Single Unix Specification says that such unused arguments are allowed."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about calls to formatted input/output functions such as \"sprintf\" and \"vsprintf\" that might overflow the destination buffer. When the exact number of bytes written by a format directive cannot be determined at compile-time it is estimated based on heuristics that depend on the level argument and on optimization. While enabling optimization will in most cases improve the accuracy of the warning, it may also result in false positives. -Wformat-overflow -Wformat-overflow=1 Level 1 of -Wformat-overflow enabled by -Wformat employs a conservative approach that warns only about calls that most likely overflow the buffer. At this level, numeric arguments to format directives with unknown values are assumed to have the value of one, and strings of unknown length to be empty. Numeric arguments that are known to be bounded to a subrange of their type, or string arguments whose output is bounded either by their directive's precision or by a finite set of string literals, are assumed to take on the value within the range that results in the most bytes on output. For example, the call to \"sprintf\" below is diagnosed because even with both a and b equal to zero, the terminating NUL character ('\\0') appended by the function to the destination buffer will be written past its end. Increasing the size of the buffer by a single byte is sufficient to avoid the warning, though it may not be sufficient to avoid the overflow. void f (int a, int b) { char buf [13]; sprintf (buf, \"a = %i, b = %i\\n\", a, b); } -Wformat-overflow=2 Level 2 warns also about calls that might overflow the destination buffer given an argument of sufficient length or magnitude. At level 2, unknown numeric arguments are assumed to have the minimum representable value for signed types with a precision greater than 1, and the maximum representable value otherwise. Unknown string arguments whose length cannot be assumed to be bounded either by the directive's precision, or by a finite set of string literals they may evaluate to, or the character array they may point to, are assumed to be 1 character long. At level 2, the call in the example above is again diagnosed, but this time because with a equal to a 32-bit \"INTMIN\" the first %i directive will write some of its digits beyond the end of the destination buffer. To make the call safe regardless of the values of the two variables, the size of the destination buffer must be increased to at least 34 bytes. GCC includes the minimum size of the buffer in an informational note following the warning. An alternative to increasing the size of the destination buffer is to constrain the range of formatted values. The maximum length of string arguments can be bounded by specifying the precision in the format directive. When numeric arguments of format directives can be assumed to be bounded by less than the precision of their type, choosing an appropriate length modifier to the format specifier will reduce the required buffer size. For example, if a and b in the example above can be assumed to be within the precision of the \"short int\" type then using either the %hi format directive or casting the argument to \"short\" reduces the maximum required size of the buffer to 24 bytes. void f (int a, int b) { char buf [23]; sprintf (buf, \"a = %hi, b = %i\\n\", a, (short)b); }"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If -Wformat is specified, do not warn about zero-length formats. The C standard specifies that zero-length formats are allowed."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If -Wformat is specified, also warn if the format string is not a string literal and so cannot be checked, unless the format function takes its format arguments as a \"valist\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If -Wformat is specified, also warn about uses of format functions that represent possible security problems. At present, this warns about calls to \"printf\" and \"scanf\" functions where the format string is not a string literal and there are no format arguments, as in \"printf (foo);\". This may be a security hole if the format string came from untrusted input and contains %n. (This is currently a subset of what -Wformat-nonliteral warns about, but in future warnings may be added to -Wformat-security that are not included in -Wformat-nonliteral.)"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If -Wformat is specified, also warn if the format string requires an unsigned argument and the argument is signed and vice versa."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about calls to formatted input/output functions such as \"snprintf\" and \"vsnprintf\" that might result in output truncation. When the exact number of bytes written by a format directive cannot be determined at compile-time it is estimated based on heuristics that depend on the level argument and on optimization. While enabling optimization will in most cases improve the accuracy of the warning, it may also result in false positives. Except as noted otherwise, the option uses the same logic -Wformat-overflow. -Wformat-truncation -Wformat-truncation=1 Level 1 of -Wformat-truncation enabled by -Wformat employs a conservative approach that warns only about calls to bounded functions whose return value is unused and that will most likely result in output truncation. -Wformat-truncation=2 Level 2 warns also about calls to bounded functions whose return value is used and that might result in truncation given an argument of sufficient length or magnitude."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If -Wformat is specified, also warn about \"strftime\" formats that may yield only a two- digit year."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about passing a null pointer for arguments marked as requiring a non-null value by the \"nonnull\" function attribute. -Wnonnull is included in -Wall and -Wformat. It can be disabled with the -Wno-nonnull option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when comparing an argument marked with the \"nonnull\" function attribute against null inside the function. -Wnonnull-compare is included in -Wall. It can be disabled with the -Wno-nonnull-compare option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if the compiler detects paths that trigger erroneous or undefined behavior due to dereferencing a null pointer. This option is only active when -fdelete-null-pointer-checks is active, which is enabled by optimizations in most targets. The precision of the warnings depends on the optimization options used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about infinitely recursive calls. The warning is effective at all optimization levels but requires optimization in order to detect infinite recursion in calls between two or more functions. -Winfinite-recursion is included in -Wall. Compare with -Wanalyzer-infinite-recursion which provides a similar diagnostic, but is implemented in a different way (as part of -fanalyzer)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about uninitialized variables that are initialized with themselves. Note this option can only be used with the -Wuninitialized option. For example, GCC warns about \"i\" being uninitialized in the following snippet only when -Winit-self has been specified: int f() { int i = i; return i; } This warning is enabled by -Wall in C++."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls warnings when a declaration does not specify a type. This warning is enabled by default in C99 and later dialects of C, and also by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls warnings when a function is used before being declared. This warning is enabled by default in C99 and later dialects of C, and also by -Wall. The warning is made into an error by -pedantic-errors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Same as -Wimplicit-int and -Wimplicit-function-declaration. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "-Wimplicit-fallthrough is the same as -Wimplicit-fallthrough=3 and -Wno-implicit-fallthrough is the same as -Wimplicit-fallthrough=0."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a switch case falls through. For example: switch (cond) { case 1: a = 1; break; case 2: a = 2; case 3: a = 3; break; } This warning does not warn when the last statement of a case cannot fall through, e.g. when there is a return statement or a call to function declared with the noreturn attribute. -Wimplicit-fallthrough= also takes into account control flow statements, such as ifs, and only warns when appropriate. E.g. switch (cond) { case 1: if (i > 3) { bar (5); break; } else if (i < 1) { bar (0); } else return; default: ... } Since there are occasions where a switch case fall through is desirable, GCC provides an attribute, \"attribute ((fallthrough))\", that is to be used along with a null statement to suppress this warning that would normally occur: switch (cond) { case 1: bar (0); attribute ((fallthrough)); default: ... } C++17 provides a standard way to suppress the -Wimplicit-fallthrough warning using \"[[fallthrough]];\" instead of the GNU attribute. In C++11 or C++14 users can use \"[[gnu::fallthrough]];\", which is a GNU extension. Instead of these attributes, it is also possible to add a fallthrough comment to silence the warning. The whole body of the C or C++ style comment should match the given regular expressions listed below. The option argument n specifies what kind of comments are accepted: *<-Wimplicit-fallthrough=0 disables the warning altogether.> *<-Wimplicit-fallthrough=1 matches \".*\" regular> expression, any comment is used as fallthrough comment. *<-Wimplicit-fallthrough=2 case insensitively matches> \".*falls?[ \\t-]*thr(ough|u).*\" regular expression. *<-Wimplicit-fallthrough=3 case sensitively matches one of the> following regular expressions: *<\"-fallthrough\"> *<\"@fallthrough@\"> *<\"lint -fallthrough[ \\t]*\"> *<\"[ \\t.!]*(ELSE,? |INTENTIONAL(LY)? )?FALL(S | |-)?THR(OUGH|U)[ \\t.!]*(-[^\\n\\r]*)?\"> *<\"[ \\t.!]*(Else,? |Intentional(ly)? )?Fall((s | |-)[Tt]|t)hr(ough|u)[ \\t.!]*(-[^\\n\\r]*)?\"> *<\"[ \\t.!]*([Ee]lse,? |[Ii]ntentional(ly)? )?fall(s | |-)?thr(ough|u)[ \\t.!]*(-[^\\n\\r]*)?\"> *<-Wimplicit-fallthrough=4 case sensitively matches one of the> following regular expressions: *<\"-fallthrough\"> *<\"@fallthrough@\"> *<\"lint -fallthrough[ \\t]*\"> *<\"[ \\t]*FALLTHR(OUGH|U)[ \\t]*\"> *<-Wimplicit-fallthrough=5 doesn't recognize any comments as> fallthrough comments, only attributes disable the warning. The comment needs to be followed after optional whitespace and other comments by \"case\" or \"default\" keywords or by a user label that precedes some \"case\" or \"default\" label. switch (cond) { case 1: bar (0); /* FALLTHRU */ default: ... } The -Wimplicit-fallthrough=3 warning is enabled by -Wextra."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Control if warnings triggered by the \"warnifnotaligned\" attribute should be issued. These warnings are enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if the return type of a function has a type qualifier such as \"const\". For ISO C such a type qualifier has no effect, since the value returned by a function is not an lvalue. For C++, the warning is only emitted for scalar types or \"void\". ISO C prohibits qualified \"void\" return types on function definitions, so such return types always receive a warning even without this option. This warning is also enabled by -Wextra."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls warnings when an attribute is ignored. This is different from the -Wattributes option in that it warns whenever the compiler decides to drop an attribute, not that the attribute is either unknown, used in a wrong place, etc. This warning is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if the type of \"main\" is suspicious. \"main\" should be a function with external linkage, returning int, taking either zero arguments, two, or three arguments of appropriate types. This warning is enabled by default in C++ and is enabled by either -Wall or -Wpedantic."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when the indentation of the code does not reflect the block structure. Specifically, a warning is issued for \"if\", \"else\", \"while\", and \"for\" clauses with a guarded statement that does not use braces, followed by an unguarded statement with the same indentation. In the following example, the call to \"bar\" is misleadingly indented as if it were guarded by the \"if\" conditional. if (somecondition ()) foo (); bar (); /* Gotcha: this is not guarded by the \"if\". */ In the case of mixed tabs and spaces, the warning uses the -ftabstop= option to determine if the statements line up (defaulting to 8). The warning is not issued for code involving multiline preprocessor logic such as the following example. if (flagA) foo (0); #if SOMECONDITIONTHATDOESNOTHOLD if (flagB) #endif foo (1); The warning is not issued after a \"#line\" directive, since this typically indicates autogenerated code, and no assumptions can be made about the layout of the file that the directive references. This warning is enabled by -Wall in C and C++."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a declaration of a function is missing one or more attributes that a related function is declared with and whose absence may adversely affect the correctness or efficiency of generated code. For example, the warning is issued for declarations of aliases that use attributes to specify less restrictive requirements than those of their targets. This typically represents a potential optimization opportunity. By contrast, the -Wattribute-alias=2 option controls warnings issued when the alias is more restrictive than the target, which could lead to incorrect code generation. Attributes considered include \"allocalign\", \"allocsize\", \"cold\", \"const\", \"hot\", \"leaf\", \"malloc\", \"nonnull\", \"noreturn\", \"nothrow\", \"pure\", \"returnsnonnull\", and \"returnstwice\". In C++, the warning is issued when an explicit specialization of a primary template declared with attribute \"allocalign\", \"allocsize\", \"assumealigned\", \"format\", \"formatarg\", \"malloc\", or \"nonnull\" is declared without it. Attributes \"deprecated\", \"error\", and \"warning\" suppress the warning.. You can use the \"copy\" attribute to apply the same set of attributes to a declaration as that on another declaration without explicitly enumerating the attributes. This attribute can be applied to declarations of functions, variables, or types. -Wmissing-attributes is enabled by -Wall. For example, since the declaration of the primary function template below makes use of both attribute \"malloc\" and \"allocsize\" the declaration of the explicit specialization of the template is diagnosed because it is missing one of the attributes. template <class T> T* attribute ((malloc, allocsize (1))) allocate (sizet); template <> void* attribute ((malloc)) // missing allocsize allocate<void> (sizet);"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if an aggregate or union initializer is not fully bracketed. In the following example, the initializer for \"a\" is not fully bracketed, but that for \"b\" is fully bracketed. int a[2][2] = { 0, 1, 2, 3 }; int b[2][2] = { { 0, 1 }, { 2, 3 } }; This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a user-supplied include directory does not exist. This option is disabled by default for C, C++, Objective-C and Objective-C++. For Fortran, it is partially enabled by default by warning for -I and -J, only."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls warnings if feedback profiles are missing when using the -fprofile-use option. This option diagnoses those cases where a new function or a new file is added between compiling with -fprofile-generate and with -fprofile-use, without regenerating the profiles. In these cases, the profile feedback data files do not contain any profile feedback information for the newly added function or file respectively. Also, in the case when profile count data (.gcda) files are removed, GCC cannot use any profile feedback information. In all these cases, warnings are issued to inform you that a profile generation step is due. Ignoring the warning can result in poorly optimized code. -Wno-missing-profile can be used to disable the warning, but this is not recommended and should be done only when non-existent profile data is justified."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for calls to deallocation functions with pointer arguments returned from from allocations functions for which the former isn't a suitable deallocator. A pair of functions can be associated as matching allocators and deallocators by use of attribute \"malloc\". Unless disabled by the -fno-builtin option the standard functions \"calloc\", \"malloc\", \"realloc\", and \"free\", as well as the corresponding forms of C++ \"operator new\" and \"operator delete\" are implicitly associated as matching allocators and deallocators. In the following example \"mydealloc\" is the deallocator for pointers returned from \"myalloc\". void mydealloc (void*); attribute ((malloc (mydealloc, 1))) void* myalloc (sizet); void f (void) { void *p = myalloc (32); // ...use p... free (p); // warning: not a matching deallocator for myalloc mydealloc (p); // ok } In C++, the related option -Wmismatched-new-delete diagnoses mismatches involving either \"operator new\" or \"operator delete\". Option -Wmismatched-dealloc is included in -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about unsafe multiple statement macros that appear to be guarded by a clause such as \"if\", \"else\", \"for\", \"switch\", or \"while\", in which only the first statement is actually guarded after the macro is expanded. For example: #define DOIT x++; y++ if (c) DOIT; will increment \"y\" unconditionally, not just when \"c\" holds. The can usually be fixed by wrapping the macro in a do-while loop: #define DOIT do { x++; y++; } while (0) if (c) DOIT; This warning is enabled by -Wall in C and C++."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if parentheses are omitted in certain contexts, such as when there is an assignment in a context where a truth value is expected, or when operators are nested whose precedence people often get confused about. Also warn if a comparison like \"x<=y<=z\" appears; this is equivalent to \"(x<=y ? 1 : 0) <= z\", which is a different interpretation from that of ordinary mathematical notation. Also warn for dangerous uses of the GNU extension to \"?:\" with omitted middle operand. When the condition in the \"?\": operator is a boolean expression, the omitted value is always 1. Often programmers expect it to be a value computed inside the conditional expression instead. For C++ this also warns for some cases of unnecessary parentheses in declarations, which can indicate an attempt at a function call instead of a declaration: { // Declares a local variable called mymutex. std::uniquelock<std::mutex> (mymutex); // User meant std::uniquelock<std::mutex> lock (mymutex); } This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning warns when a value is moved to itself with \"std::move\". Such a \"std::move\" typically has no effect. struct T { ... }; void fn() { T t; ... t = std::move (t); } This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about code that may have undefined semantics because of violations of sequence point rules in the C and C++ standards. The C and C++ standards define the order in which expressions in a C/C++ program are evaluated in terms of sequence points, which represent a partial ordering between the execution of parts of the program: those executed before the sequence point, and those executed after it. These occur after the evaluation of a full expression (one which is not part of a larger expression), after the evaluation of the first operand of a \"&&\", \"||\", \"? :\" or \",\" (comma) operator, before a function is called (but after the evaluation of its arguments and the expression denoting the called function), and in certain other places. Other than as expressed by the sequence point rules, the order of evaluation of subexpressions of an expression is not specified. All these rules describe only a partial order rather than a total order, since, for example, if two functions are called within one expression with no sequence point between them, the order in which the functions are called is not specified. However, the standards committee have ruled that function calls do not overlap. It is not specified when between sequence points modifications to the values of objects take effect. Programs whose behavior depends on this have undefined behavior; the C and C++ standards specify that \"Between the previous and next sequence point an object shall have its stored value modified at most once by the evaluation of an expression. Furthermore, the prior value shall be read only to determine the value to be stored.\". If a program breaks these rules, the results on any particular implementation are entirely unpredictable. Examples of code with undefined behavior are \"a = a++;\", \"a[n] = b[n++]\" and \"a[i++] = i;\". Some more complicated cases are not diagnosed by this option, and it may give an occasional false positive result, but in general it has been found fairly effective at detecting this sort of problem in programs. The C++17 standard will define the order of evaluation of operands in more cases: in particular it requires that the right-hand side of an assignment be evaluated before the left-hand side, so the above examples are no longer undefined. But this option will still warn about them, to help people avoid writing code that is undefined in C and earlier revisions of C++. The standard is worded confusingly, therefore there is some debate over the precise meaning of the sequence point rules in subtle cases. Links to discussions of the problem, including proposed formal definitions, may be found on the GCC readings page, at <https://gcc.gnu.org/readings.html>. This warning is enabled by -Wall for C and C++."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn about returning a pointer (or in C++, a reference) to a variable that goes out of scope after the function returns."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a function is defined with a return type that defaults to \"int\". Also warn about any \"return\" statement with no return value in a function whose return type is not \"void\" (falling off the end of the function body is considered returning without a value). For C only, warn about a \"return\" statement with an expression in a function whose return type is \"void\", unless the expression type is also \"void\". As a GNU extension, the latter case is accepted without a warning unless -Wpedantic is used. Attempting to use the return value of a non-\"void\" function other than \"main\" that flows off the end by reaching the closing curly brace that terminates the function is undefined. Unlike in C, in C++, flowing off the end of a non-\"void\" function other than \"main\" results in undefined behavior even when the value of the function is not used. This warning is enabled by default in C++ and by -Wall otherwise."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Controls warnings if a shift count is negative. This warning is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Controls warnings if a shift count is greater than or equal to the bit width of the type. This warning is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if left shifting a negative value. This warning is enabled by -Wextra in C99 (and newer) and C++11 to C++17 modes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These options control warnings about left shift overflows. -Wshift-overflow=1 This is the warning level of -Wshift-overflow and is enabled by default in C99 and C++11 modes (and newer). This warning level does not warn about left-shifting 1 into the sign bit. (However, in C, such an overflow is still rejected in contexts where an integer constant expression is required.) No warning is emitted in C++20 mode (and newer), as signed left shifts always wrap. -Wshift-overflow=2 This warning level also warns about left-shifting 1 into the sign bit, unless C++14 mode (or newer) is active."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a \"switch\" statement has an index of enumerated type and lacks a \"case\" for one or more of the named codes of that enumeration. (The presence of a \"default\" label prevents this warning.) \"case\" labels outside the enumeration range also provoke warnings when this option is used (even if there is a \"default\" label). This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a \"switch\" statement does not have a \"default\" case."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a \"switch\" statement has an index of enumerated type and lacks a \"case\" for one or more of the named codes of that enumeration. \"case\" labels outside the enumeration range also provoke warnings when this option is used. The only difference between -Wswitch and this option is that this option gives a warning about an omitted enumeration code even if there is a \"default\" label."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn when a \"switch\" statement has an index of boolean type and the case values are outside the range of a boolean type. It is possible to suppress this warning by casting the controlling expression to a type other than \"bool\". For example: switch ((int) (a == 4)) { ... } This warning is enabled by default for C and C++ programs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls warnings when a \"switch\" case has a value that is outside of its respective type range. This warning is enabled by default for C and C++ programs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn when a \"switch\" statement contains statements between the controlling expression and the first case label, which will never be executed. For example: switch (cond) { i = 15; ... case 5: ... } -Wswitch-unreachable does not warn if the statement between the controlling expression and the first case label is just a declaration: switch (cond) { int i; ... case 5: i = 5; ... } This warning is enabled by default for C and C++ programs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when \"syncfetchandnand\" and \"syncnandandfetch\" built-in functions are used. These functions changed semantics in GCC 4.4."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when \"-ftrivial-auto-var-init\" cannot initialize the automatic variable. A common situation is an automatic variable that is declared between the controlling expression and the first case label of a \"switch\" statement."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a function parameter is assigned to, but otherwise unused (aside from its declaration). To suppress this warning use the \"unused\" attribute. This warning is also enabled by -Wunused together with -Wextra."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a local variable is assigned to, but otherwise unused (aside from its declaration). This warning is enabled by -Wall. To suppress this warning use the \"unused\" attribute. This warning is also enabled by -Wunused, which is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a static function is declared but not defined or a non-inline static function is unused. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a label is declared but not used. This warning is enabled by -Wall. To suppress this warning use the \"unused\" attribute."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a typedef locally defined in a function is not used. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a function parameter is unused aside from its declaration. To suppress this warning use the \"unused\" attribute."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn if a caller of a function marked with attribute \"warnunusedresult\" does not use its return value. The default is -Wunused-result."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a local or static variable is unused aside from its declaration. This option implies -Wunused-const-variable=1 for C, but not for C++. This warning is enabled by -Wall. To suppress this warning use the \"unused\" attribute."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a constant static variable is unused aside from its declaration. -Wunused-const-variable=1 is enabled by -Wunused-variable for C, but not for C++. In C this declares variable storage, but in C++ this is not an error since const variables take the place of \"#define\"s. To suppress this warning use the \"unused\" attribute. -Wunused-const-variable=1 This is the warning level that is enabled by -Wunused-variable for C. It warns only about unused static const variables defined in the main compilation unit, but not about static const variables declared in any header included. -Wunused-const-variable=2 This warning level also warns for unused constant static variables in headers (excluding system headers). This is the warning level of -Wunused-const-variable and must be explicitly requested since in C++ this isn't an error and in C it might be harder to clean up all headers included."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a statement computes a result that is explicitly not used. To suppress this warning cast the unused expression to \"void\". This includes an expression-statement or the left-hand side of a comma expression that contains no side effects. For example, an expression such as \"x[i,j]\" causes a warning, while \"x[(void)i,j]\" does not. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "All the above -Wunused options combined. In order to get a warning about an unused function parameter, you must either specify -Wextra -Wunused (note that -Wall implies -Wunused), or separately specify -Wunused-parameter."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if an object with automatic or allocated storage duration is used without having been initialized. In C++, also warn if a non-static reference or non-static \"const\" member appears in a class without constructors. In addition, passing a pointer (or in C++, a reference) to an uninitialized object to a \"const\"-qualified argument of a built-in function known to read the object is also diagnosed by this warning. (-Wmaybe-uninitialized is issued for ordinary functions.) If you want to warn about code that uses the uninitialized value of the variable in its own initializer, use the -Winit-self option. These warnings occur for individual uninitialized elements of structure, union or array variables as well as for variables that are uninitialized as a whole. They do not occur for variables or elements declared \"volatile\". Because these warnings depend on optimization, the exact variables or elements for which there are warnings depend on the precise optimization options and version of GCC used. Note that there may be no warning about a variable that is used only to compute a value that itself is never used, because such computations may be deleted by data flow analysis before the warnings are printed. In C++, this warning also warns about using uninitialized objects in member-initializer- lists. For example, GCC warns about \"b\" being uninitialized in the following snippet: struct A { int a; int b; A() : a(b) { } };"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls warnings for invocations of atomic Builtins, sync Builtins, and the C11 atomic generic functions with a memory consistency argument that is either invalid for the operation or outside the range of values of the \"memoryorder\" enumeration. For example, since the \"atomicstore\" and \"atomicstoren\" built-ins are only defined for the relaxed, release, and sequentially consistent memory orders the following code is diagnosed: void store (int *i) { atomicstoren (i, 0, memoryorderconsume); } -Winvalid-memory-model is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "For an object with automatic or allocated storage duration, if there exists a path from the function entry to a use of the object that is initialized, but there exist some other paths for which the object is not initialized, the compiler emits a warning if it cannot prove the uninitialized paths are not executed at run time. In addition, passing a pointer (or in C++, a reference) to an uninitialized object to a \"const\"-qualified function argument is also diagnosed by this warning. (-Wuninitialized is issued for built-in functions known to read the object.) Annotating the function with attribute \"access (none)\" indicates that the argument isn't used to access the object and avoids the warning. These warnings are only possible in optimizing compilation, because otherwise GCC does not keep track of the state of variables. These warnings are made optional because GCC may not be able to determine when the code is correct in spite of appearing to have an error. Here is one example of how this can happen: { int x; switch (y) { case 1: x = 1; break; case 2: x = 4; break; case 3: x = 5; } foo (x); } If the value of \"y\" is always 1, 2 or 3, then \"x\" is always initialized, but GCC doesn't know this. To suppress the warning, you need to provide a default case with assert(0) or similar code. This option also warns when a non-volatile automatic variable might be changed by a call to \"longjmp\". The compiler sees only the calls to \"setjmp\". It cannot know where \"longjmp\" will be called; in fact, a signal handler could call it at any point in the code. As a result, you may get a warning even when there is in fact no problem because \"longjmp\" cannot in fact be called at the place that would cause a problem. Some spurious warnings can be avoided if you declare all the functions you use that never return as \"noreturn\". This warning is enabled by -Wall or -Wextra."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a \"#pragma\" directive is encountered that is not understood by GCC. If this command-line option is used, warnings are even issued for unknown pragmas in system header files. This is not the case if the warnings are only enabled by the -Wall command-line option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn about misuses of pragmas, such as incorrect parameters, invalid syntax, or conflicts between pragmas. See also -Wunknown-pragmas."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn if a priority from 0 to 100 is used for constructor or destructor. The use of constructor and destructor attributes allow you to assign a priority to the constructor/destructor to control its order of execution before \"main\" is called or after it returns. The priority values must be greater than 100 as the compiler reserves priority values between 0--100 for the implementation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is only active when -fstrict-aliasing is active. It warns about code that might break the strict aliasing rules that the compiler is using for optimization. The warning does not catch all cases, but does attempt to catch the more common pitfalls. It is included in -Wall. It is equivalent to -Wstrict-aliasing=3"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is only active when -fstrict-aliasing is active. It warns about code that might break the strict aliasing rules that the compiler is using for optimization. Higher levels correspond to higher accuracy (fewer false positives). Higher levels also correspond to more effort, similar to the way -O works. -Wstrict-aliasing is equivalent to -Wstrict-aliasing=3. Level 1: Most aggressive, quick, least accurate. Possibly useful when higher levels do not warn but -fstrict-aliasing still breaks the code, as it has very few false negatives. However, it has many false positives. Warns for all pointer conversions between possibly incompatible types, even if never dereferenced. Runs in the front end only. Level 2: Aggressive, quick, not too precise. May still have many false positives (not as many as level 1 though), and few false negatives (but possibly more than level 1). Unlike level 1, it only warns when an address is taken. Warns about incomplete types. Runs in the front end only. Level 3 (default for -Wstrict-aliasing): Should have very few false positives and few false negatives. Slightly slower than levels 1 or 2 when optimization is enabled. Takes care of the common pun+dereference pattern in the front end: \"*(int*)&somefloat\". If optimization is enabled, it also runs in the back end, where it deals with multiple statement cases using flow-sensitive points-to information. Only warns when the converted pointer is dereferenced. Does not warn about incomplete types."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is only active when signed overflow is undefined. It warns about cases where the compiler optimizes based on the assumption that signed overflow does not occur. Note that it does not warn about all cases where the code might overflow: it only warns about cases where the compiler implements some optimization. Thus this warning depends on the optimization level. An optimization that assumes that signed overflow does not occur is perfectly safe if the values of the variables involved are such that overflow never does, in fact, occur. Therefore this warning can easily give a false positive: a warning about code that is not actually a problem. To help focus on important issues, several warning levels are defined. No warnings are issued for the use of undefined signed overflow when estimating how many iterations a loop requires, in particular when determining whether a loop will be executed at all. -Wstrict-overflow=1 Warn about cases that are both questionable and easy to avoid. For example the compiler simplifies \"x + 1 > x\" to 1. This level of -Wstrict-overflow is enabled by -Wall; higher levels are not, and must be explicitly requested. -Wstrict-overflow=2 Also warn about other cases where a comparison is simplified to a constant. For example: \"abs (x) >= 0\". This can only be simplified when signed integer overflow is undefined, because \"abs (INTMIN)\" overflows to \"INTMIN\", which is less than zero. -Wstrict-overflow (with no level) is the same as -Wstrict-overflow=2. -Wstrict-overflow=3 Also warn about other cases where a comparison is simplified. For example: \"x + 1 > 1\" is simplified to \"x > 0\". -Wstrict-overflow=4 Also warn about other simplifications not covered by the above cases. For example: \"(x * 10) / 5\" is simplified to \"x * 2\". -Wstrict-overflow=5 Also warn about cases where the compiler reduces the magnitude of a constant involved in a comparison. For example: \"x + 2 > y\" is simplified to \"x + 1 >= y\". This is reported only at the highest warning level because this simplification applies to many comparisons, so this warning level gives a very large number of false positives."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for calls to \"strcmp\" and \"strncmp\" whose result is determined to be either zero or non-zero in tests for such equality owing to the length of one argument being greater than the size of the array the other argument is stored in (or the bound in the case of \"strncmp\"). Such calls could be mistakes. For example, the call to \"strcmp\" below is diagnosed because its result is necessarily non-zero irrespective of the contents of the array \"a\". extern char a[4]; void f (char *d) { strcpy (d, \"string\"); ... if (0 == strcmp (a, d)) // cannot be true puts (\"a and d are the same\"); } -Wstring-compare is enabled by -Wextra."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for calls to string manipulation functions such as \"memcpy\" and \"strcpy\" that are determined to overflow the destination buffer. The optional argument is one greater than the type of Object Size Checking to perform to determine the size of the destination. The argument is meaningful only for functions that operate on character arrays but not for raw memory functions like \"memcpy\" which always make use of Object Size type-0. The option also warns for calls that specify a size in excess of the largest possible object or at most \"SIZEMAX / 2\" bytes. The option produces the best results with optimization enabled but can detect a small subset of simple buffer overflows even without optimization in calls to the GCC built-in functions like \"builtinmemcpy\" that correspond to the standard functions. In any case, the option warns about just a subset of buffer overflows detected by the corresponding overflow checking built-ins. For example, the option issues a warning for the \"strcpy\" call below because it copies at least 5 characters (the string \"blue\" including the terminating NUL) into the buffer of size 4. enum Color { blue, purple, yellow }; const char* f (enum Color clr) { static char buf [4]; const char *str; switch (clr) { case blue: str = \"blue\"; break; case purple: str = \"purple\"; break; case yellow: str = \"yellow\"; break; } return strcpy (buf, str); // warning here } Option -Wstringop-overflow=2 is enabled by default. -Wstringop-overflow -Wstringop-overflow=1 The -Wstringop-overflow=1 option uses type-zero Object Size Checking to determine the sizes of destination objects. At this setting the option does not warn for writes past the end of subobjects of larger objects accessed by pointers unless the size of the largest surrounding object is known. When the destination may be one of several objects it is assumed to be the largest one of them. On Linux systems, when optimization is enabled at this setting the option warns for the same code as when the \"FORTIFYSOURCE\" macro is defined to a non-zero value. -Wstringop-overflow=2 The -Wstringop-overflow=2 option uses type-one Object Size Checking to determine the sizes of destination objects. At this setting the option warns about overflows when writing to members of the largest complete objects whose exact size is known. However, it does not warn for excessive writes to the same members of unknown objects referenced by pointers since they may point to arrays containing unknown numbers of elements. This is the default setting of the option. -Wstringop-overflow=3 The -Wstringop-overflow=3 option uses type-two Object Size Checking to determine the sizes of destination objects. At this setting the option warns about overflowing the smallest object or data member. This is the most restrictive setting of the option that may result in warnings for safe code. -Wstringop-overflow=4 The -Wstringop-overflow=4 option uses type-three Object Size Checking to determine the sizes of destination objects. At this setting the option warns about overflowing any data members, and when the destination is one of several objects it uses the size of the largest of them to decide whether to issue a warning. Similarly to -Wstringop-overflow=3 this setting of the option may result in warnings for benign code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for calls to string manipulation functions such as \"memchr\", or \"strcpy\" that are determined to read past the end of the source sequence. Option -Wstringop-overread is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn for calls to bounded string manipulation functions such as \"strncat\", \"strncpy\", and \"stpncpy\" that may either truncate the copied string or leave the destination unchanged. In the following example, the call to \"strncat\" specifies a bound that is less than the length of the source string. As a result, the copy of the source will be truncated and so the call is diagnosed. To avoid the warning use \"bufsize - strlen (buf) - 1)\" as the bound. void append (char *buf, sizet bufsize) { strncat (buf, \".txt\", 3); } As another example, the following call to \"strncpy\" results in copying to \"d\" just the characters preceding the terminating NUL, without appending the NUL to the end. Assuming the result of \"strncpy\" is necessarily a NUL-terminated string is a common mistake, and so the call is diagnosed. To avoid the warning when the result is not expected to be NUL-terminated, call \"memcpy\" instead. void copy (char *d, const char *s) { strncpy (d, s, strlen (s)); } In the following example, the call to \"strncpy\" specifies the size of the destination buffer as the bound. If the length of the source string is equal to or greater than this size the result of the copy will not be NUL-terminated. Therefore, the call is also diagnosed. To avoid the warning, specify \"sizeof buf - 1\" as the bound and set the last element of the buffer to \"NUL\". void copy (const char *s) { char buf[80]; strncpy (buf, s, sizeof buf); ... } In situations where a character array is intended to store a sequence of bytes with no terminating \"NUL\" such an array may be annotated with attribute \"nonstring\" to avoid this warning. Such arrays, however, are not suitable arguments to functions that expect \"NUL\"-terminated strings. To help detect accidental misuses of such arrays GCC issues warnings unless it can prove that the use is safe."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about inproper usages of flexible array members according to the level of the \"strictflexarray (level)\" attribute attached to the trailing array field of a structure if it's available, otherwise according to the level of the option -fstrict-flex-arrays=level. This option is effective only when level is bigger than 0. Otherwise, it will be ignored with a warning. when level=1, warnings will be issued for a trailing array reference of a structure that have 2 or more elements if the trailing array is referenced as a flexible array member. when level=2, in addition to level=1, additional warnings will be issued for a trailing one-element array reference of a structure if the array is referenced as a flexible array member. when level=3, in addition to level=2, additional warnings will be issued for a trailing zero-length array reference of a structure if the array is referenced as a flexible array member."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for cases where adding an attribute may be beneficial. The attributes currently supported are listed below. -Wsuggest-attribute=pure -Wsuggest-attribute=const -Wsuggest-attribute=noreturn -Wmissing-noreturn -Wsuggest-attribute=malloc Warn about functions that might be candidates for attributes \"pure\", \"const\" or \"noreturn\" or \"malloc\". The compiler only warns for functions visible in other compilation units or (in the case of \"pure\" and \"const\") if it cannot prove that the function returns normally. A function returns normally if it doesn't contain an infinite loop or return abnormally by throwing, calling \"abort\" or trapping. This analysis requires option -fipa-pure-const, which is enabled by default at -O and higher. Higher optimization levels improve the accuracy of the analysis. -Wsuggest-attribute=format -Wmissing-format-attribute Warn about function pointers that might be candidates for \"format\" attributes. Note these are only possible candidates, not absolute ones. GCC guesses that function pointers with \"format\" attributes that are used in assignment, initialization, parameter passing or return statements should have a corresponding \"format\" attribute in the resulting type. I.e. the left-hand side of the assignment or initialization, the type of the parameter variable, or the return type of the containing function respectively should also have a \"format\" attribute to avoid the warning. GCC also warns about function definitions that might be candidates for \"format\" attributes. Again, these are only possible candidates. GCC guesses that \"format\" attributes might be appropriate for any function that calls a function like \"vprintf\" or \"vscanf\", but this might not always be the case, and some functions for which \"format\" attributes are appropriate may not be detected. -Wsuggest-attribute=cold Warn about functions that might be candidates for \"cold\" attribute. This is based on static detection and generally only warns about functions which always leads to a call to another \"cold\" function such as wrappers of C++ \"throw\" or fatal error reporting functions leading to \"abort\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about calls to allocation functions decorated with attribute \"allocsize\" that specify zero bytes, including those to the built-in forms of the functions \"alignedalloc\", \"alloca\", \"calloc\", \"malloc\", and \"realloc\". Because the behavior of these functions when called with a zero size differs among implementations (and in the case of \"realloc\" has been deprecated) relying on it may result in subtle portability bugs and should be avoided."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about calls to functions decorated with attribute \"allocsize\" that attempt to allocate objects larger than the specified number of bytes, or where the result of the size computation in an integer type with infinite precision would exceed the value of PTRDIFFMAX on the target. -Walloc-size-larger-than=PTRDIFFMAX is enabled by default. Warnings controlled by the option can be disabled either by specifying byte-size of SIZEMAX or more or by -Wno-alloc-size-larger-than."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable -Walloc-size-larger-than= warnings. The option is equivalent to -Walloc-size-larger-than=SIZEMAX or larger."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option warns on all uses of \"alloca\" in the source."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option warns on calls to \"alloca\" with an integer argument whose value is either zero, or that is not bounded by a controlling predicate that limits its value to at most byte-size. It also warns for calls to \"alloca\" where the bound value is unknown. Arguments of non-integer types are considered unbounded even if they appear to be constrained to the expected range. For example, a bounded case of \"alloca\" could be: void func (sizet n) { void *p; if (n <= 1000) p = alloca (n); else p = malloc (n); f (p); } In the above example, passing \"-Walloca-larger-than=1000\" would not issue a warning because the call to \"alloca\" is known to be at most 1000 bytes. However, if \"-Walloca-larger-than=500\" were passed, the compiler would emit a warning. Unbounded uses, on the other hand, are uses of \"alloca\" with no controlling predicate constraining its integer argument. For example: void func () { void *p = alloca (n); f (p); } If \"-Walloca-larger-than=500\" were passed, the above would trigger a warning, but this time because of the lack of bounds checking. Note, that even seemingly correct code involving signed integers could cause a warning: void func (signed int n) { if (n < 500) { p = alloca (n); f (p); } } In the above example, n could be negative, causing a larger than expected argument to be implicitly cast into the \"alloca\" call. This option also warns when \"alloca\" is used in a loop. -Walloca-larger-than=PTRDIFFMAX is enabled by default but is usually only effective when -ftree-vrp is active (default for -O2 and above). See also -Wvla-larger-than=byte-size."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable -Walloca-larger-than= warnings. The option is equivalent to -Walloca-larger-than=SIZEMAX or larger."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do warn about implicit conversions from arithmetic operations even when conversion of the operands to the same type cannot change their values. This affects warnings from -Wconversion, -Wfloat-conversion, and -Wsign-conversion. void f (char c, int i) { c = c + i; // warns with B<-Wconversion> c = c + 1; // only warns with B<-Warith-conversion> }"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about out of bounds subscripts or offsets into arrays. This warning is enabled by -Wall. It is more effective when -ftree-vrp is active (the default for -O2 and above) but a subset of instances are issued even without optimization. By default, the trailing array of a structure will be treated as a flexible array member by -Warray-bounds or -Warray-bounds=n if it is declared as either a flexible array member per C99 standard onwards ([]), a GCC zero-length array extension ([0]), or an one-element array ([1]). As a result, out of bounds subscripts or offsets into zero-length arrays or one-element arrays are not warned by default. You can add the option -fstrict-flex-arrays or -fstrict-flex-arrays=level to control how this option treat trailing array of a structure as a flexible array member: when level<=1, no change to the default behavior. when level=2, additional warnings will be issued for out of bounds subscripts or offsets into one-element arrays; when level=3, in addition to level=2, additional warnings will be issued for out of bounds subscripts or offsets into zero-length arrays. -Warray-bounds=1 This is the default warning level of -Warray-bounds and is enabled by -Wall; higher levels are not, and must be explicitly requested. -Warray-bounds=2 This warning level also warns about the intermediate results of pointer arithmetic that may yield out of bounds values. This warning level may give a larger number of false positives and is deactivated by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about equality and relational comparisons between two operands of array type. This comparison was deprecated in C++20. For example: int arr1[5]; int arr2[5]; bool same = arr1 == arr2; -Warray-compare is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about redeclarations of functions involving arguments of array or pointer types of inconsistent kinds or forms, and enable the detection of out-of-bounds accesses to such parameters by warnings such as -Warray-bounds. If the first function declaration uses the array form the bound specified in the array is assumed to be the minimum number of elements expected to be provided in calls to the function and the maximum number of elements accessed by it. Failing to provide arguments of sufficient size or accessing more than the maximum number of elements may be diagnosed by warnings such as -Warray-bounds. At level 1 the warning diagnoses inconsistencies involving array parameters declared using the \"T[static N]\" form. For example, the warning triggers for the following redeclarations because the first one allows an array of any size to be passed to \"f\" while the second one with the keyword \"static\" specifies that the array argument must have at least four elements. void f (int[static 4]); void f (int[]); // warning (inconsistent array form) void g (void) { int *p = (int *)malloc (4); f (p); // warning (array too small) ... } At level 2 the warning also triggers for redeclarations involving any other inconsistency in array or pointer argument forms denoting array sizes. Pointers and arrays of unspecified bound are considered equivalent and do not trigger a warning. void g (int*); void g (int[]); // no warning void g (int[8]); // warning (inconsistent array bound) -Warray-parameter=2 is included in -Wall. The -Wvla-parameter option triggers warnings for similar inconsistencies involving Variable Length Array arguments."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about declarations using the \"alias\" and similar attributes whose target is incompatible with the type of the alias. -Wattribute-alias=1 The default warning level of the -Wattribute-alias option diagnoses incompatibilities between the type of the alias declaration and that of its target. Such incompatibilities are typically indicative of bugs. -Wattribute-alias=2 At this level -Wattribute-alias also diagnoses cases where the attributes of the alias declaration are more restrictive than the attributes applied to its target. These mismatches can potentially result in incorrect code generation. In other cases they may be benign and could be resolved simply by adding the missing attribute to the target. For comparison, see the -Wmissing-attributes option, which controls diagnostics when the alias declaration is less restrictive than the target, rather than more restrictive. Attributes considered include \"allocalign\", \"allocsize\", \"cold\", \"const\", \"hot\", \"leaf\", \"malloc\", \"nonnull\", \"noreturn\", \"nothrow\", \"pure\", \"returnsnonnull\", and \"returnstwice\". -Wattribute-alias is equivalent to -Wattribute-alias=1. This is the default. You can disable these warnings with either -Wno-attribute-alias or -Wattribute-alias=0."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about possibly misleading UTF-8 bidirectional control characters in comments, string literals, character constants, and identifiers. Such characters can change left-to-right writing direction into right-to-left (and vice versa), which can cause confusion between the logical order and visual order. This may be dangerous; for instance, it may seem that a piece of code is not commented out, whereas it in fact is. There are three levels of warning supported by GCC. The default is -Wbidi-chars=unpaired, which warns about improperly terminated bidi contexts. -Wbidi-chars=none turns the warning off. -Wbidi-chars=any warns about any use of bidirectional control characters. By default, this warning does not warn about UCNs. It is, however, possible to turn on such checking by using -Wbidi-chars=unpaired,ucn or -Wbidi-chars=any,ucn. Using -Wbidi-chars=ucn is valid, and is equivalent to -Wbidi-chars=unpaired,ucn, if no previous -Wbidi-chars=any was specified."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about boolean expression compared with an integer value different from \"true\"/\"false\". For instance, the following comparison is always false: int n = 5; ... if ((n > 1) == 2) { ... } This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about suspicious operations on expressions of a boolean type. For instance, bitwise negation of a boolean is very likely a bug in the program. For C, this warning also warns about incrementing or decrementing a boolean, which rarely makes sense. (In C++, decrementing a boolean is always invalid. Incrementing a boolean is invalid in C++17, and deprecated otherwise.) This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when an if-else has identical branches. This warning detects cases like if (p != NULL) return 0; else return 0; It doesn't warn when both branches contain just a null statement. This warning also warn for conditional operators: int i = x ? *p : *p;"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about duplicated conditions in an if-else-if chain. For instance, warn for the following code: if (p->q != NULL) { ... } else if (p->q != NULL) { ... }"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when the builtinframeaddress or builtinreturnaddress is called with an argument greater than 0. Such calls may return indeterminate values or crash the program. The warning is included in -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn if type qualifiers on pointers are being discarded. Typically, the compiler warns if a \"const char *\" variable is passed to a function that takes a \"char *\" parameter. This option can be used to suppress such a warning."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn if type qualifiers on arrays which are pointer targets are being discarded. Typically, the compiler warns if a \"const int (*)[]\" variable is passed to a function that takes a \"int (*)[]\" parameter. This option can be used to suppress such a warning."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn when there is a conversion between pointers that have incompatible types. This warning is for cases not covered by -Wno-pointer-sign, which warns for pointer argument passing or assignment with different signedness."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn about incompatible integer to pointer and pointer to integer conversions. This warning is about implicit conversions; for explicit conversions the warnings -Wno-int-to-pointer-cast and -Wno-pointer-to-int-cast may be used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about accesses to elements of zero-length array members that might overlap other members of the same object. Declaring interior zero-length arrays is discouraged because accesses to them are undefined. For example, the first two stores in function \"bad\" are diagnosed because the array elements overlap the subsequent members \"b\" and \"c\". The third store is diagnosed by -Warray-bounds because it is beyond the bounds of the enclosing object. struct X { int a[0]; int b, c; }; struct X x; void bad (void) { x.a[0] = 0; // -Wzero-length-bounds x.a[1] = 1; // -Wzero-length-bounds x.a[2] = 2; // -Warray-bounds } Option -Wzero-length-bounds is enabled by -Warray-bounds."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn about compile-time integer division by zero. Floating-point division by zero is not warned about, as it can be a legitimate way of obtaining infinities and NaNs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print warning messages for constructs found in system header files. Warnings from system headers are normally suppressed, on the assumption that they usually do not indicate real problems and would only make the compiler output harder to read. Using this command-line option tells GCC to emit warnings from system headers as if they occurred in user code. However, note that using -Wall in conjunction with this option does not warn about unknown pragmas in system headers---for that, -Wunknown-pragmas must also be used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a self-comparison always evaluates to true or false. This warning detects various mistakes such as: int i = 1; ... if (i > i) { ... } This warning also warns about bitwise comparisons that always evaluate to true or false, for instance: if ((a & 16) == 10) { ... } will always be false. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about trampolines generated for pointers to nested functions. A trampoline is a small piece of data or code that is created at run time on the stack when the address of a nested function is taken, and is used to call the nested function indirectly. For some targets, it is made up of data only and thus requires no special treatment. But, for most targets, it is made up of code and thus requires the stack to be made executable in order for the program to work properly."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if floating-point values are used in equality comparisons. The idea behind this is that sometimes it is convenient (for the programmer) to consider floating-point values as approximations to infinitely precise real numbers. If you are doing this, then you need to compute (by analyzing the code, or in some other way) the maximum or likely maximum error that the computation introduces, and allow for it when performing comparisons (and when producing output, but that's a different problem). In particular, instead of testing for equality, you should check to see whether the two values have ranges that overlap; and this is done with the relational operators, so equality comparisons are probably mistaken."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about certain constructs that behave differently in traditional and ISO C. Also warn about ISO C constructs that have no traditional C equivalent, and/or problematic constructs that should be avoided. * Macro parameters that appear within string literals in the macro body. In traditional C macro replacement takes place within string literals, but in ISO C it does not. * In traditional C, some preprocessor directives did not exist. Traditional preprocessors only considered a line to be a directive if the # appeared in column 1 on the line. Therefore -Wtraditional warns about directives that traditional C understands but ignores because the # does not appear as the first character on the line. It also suggests you hide directives like \"#pragma\" not understood by traditional C by indenting them. Some traditional implementations do not recognize \"#elif\", so this option suggests avoiding it altogether. * A function-like macro that appears without arguments. * The unary plus operator. * The U integer constant suffix, or the F or L floating-point constant suffixes. (Traditional C does support the L suffix on integer constants.) Note, these suffixes appear in macros defined in the system headers of most modern systems, e.g. the MIN/MAX macros in \"<limits.h>\". Use of these macros in user code might normally lead to spurious warnings, however GCC's integrated preprocessor has enough context to avoid warning in these cases. * A function declared external in one block and then used after the end of the block. * A \"switch\" statement has an operand of type \"long\". * A non-\"static\" function declaration follows a \"static\" one. This construct is not accepted by some traditional C compilers. * The ISO type of an integer constant has a different width or signedness from its traditional type. This warning is only issued if the base of the constant is ten. I.e. hexadecimal or octal values, which typically represent bit patterns, are not warned about. * Usage of ISO string concatenation is detected. * Initialization of automatic aggregates. * Identifier conflicts with labels. Traditional C lacks a separate namespace for labels. * Initialization of unions. If the initializer is zero, the warning is omitted. This is done under the assumption that the zero initializer in user code appears conditioned on e.g. \"STDC\" to avoid missing initializer warnings and relies on default initialization to zero in the traditional C case. * Conversions by prototypes between fixed/floating-point values and vice versa. The absence of these prototypes when compiling with traditional C causes serious problems. This is a subset of the possible conversion warnings; for the full set use -Wtraditional-conversion. * Use of ISO C style function definitions. This warning intentionally is not issued for prototype declarations or variadic functions because these ISO C features appear in your code when using libiberty's traditional C compatibility macros, \"PARAMS\" and \"VPARAMS\". This warning is also bypassed for nested functions because that feature is already a GCC extension and thus not relevant to traditional C compatibility."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a prototype causes a type conversion that is different from what would happen to the same argument in the absence of a prototype. This includes conversions of fixed point to floating and vice versa, and conversions changing the width or signedness of a fixed-point argument except when the same as the default promotion."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a declaration is found after a statement in a block. This construct, known from C++, was introduced with ISO C99 and is by default allowed in GCC. It is not supported by ISO C90."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a local variable or type declaration shadows another variable, parameter, type, class member (in C++), or instance variable (in Objective-C) or whenever a built-in function is shadowed. Note that in C++, the compiler warns if a local variable shadows an explicit typedef, but not if it shadows a struct/class/enum. If this warning is enabled, it includes also all instances of local shadowing. This means that -Wno-shadow=local and -Wno-shadow=compatible-local are ignored when -Wshadow is used. Same as -Wshadow=global."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn whenever a local variable shadows an instance variable in an Objective-C method."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for any shadowing. Same as -Wshadow."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a local variable shadows another local variable or parameter."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a local variable shadows another local variable or parameter whose type is compatible with that of the shadowing variable. In C++, type compatibility here means the type of the shadowing variable can be converted to that of the shadowed variable. The creation of this flag (in addition to -Wshadow=local) is based on the idea that when a local variable shadows another one of incompatible type, it is most likely intentional, not a bug or typo, as shown in the following example: for (SomeIterator i = SomeObj.begin(); i != SomeObj.end(); ++i) { for (int i = 0; i < N; ++i) { ... } ... } Since the two variable \"i\" in the example above have incompatible types, enabling only -Wshadow=compatible-local does not emit a warning. Because their types are incompatible, if a programmer accidentally uses one in place of the other, type checking is expected to catch that and emit an error or warning. Use of this flag instead of -Wshadow=local can possibly reduce the number of warnings triggered by intentional shadowing. Note that this also means that shadowing \"const char *i\" by \"char *i\" does not emit a warning. This warning is also enabled by -Wshadow=local."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever an object is defined whose size exceeds byte-size. -Wlarger-than=PTRDIFFMAX is enabled by default. Warnings controlled by the option can be disabled either by specifying byte-size of SIZEMAX or more or by -Wno-larger-than. Also warn for calls to bounded functions such as \"memchr\" or \"strnlen\" that specify a bound greater than the largest possible object, which is PTRDIFFMAX bytes by default. These warnings can only be disabled by -Wno-larger-than."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable -Wlarger-than= warnings. The option is equivalent to -Wlarger-than=SIZEMAX or larger."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if the size of a function frame exceeds byte-size. The computation done to determine the stack frame size is approximate and not conservative. The actual requirements may be somewhat greater than byte-size even if you do not get a warning. In addition, any space allocated via \"alloca\", variable-length arrays, or related constructs is not included by the compiler when determining whether or not to issue a warning. -Wframe-larger-than=PTRDIFFMAX is enabled by default. Warnings controlled by the option can be disabled either by specifying byte-size of SIZEMAX or more or by -Wno-frame-larger-than."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable -Wframe-larger-than= warnings. The option is equivalent to -Wframe-larger-than=SIZEMAX or larger."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when attempting to deallocate an object that was either not allocated on the heap, or by using a pointer that was not returned from a prior call to the corresponding allocation function. For example, because the call to \"stpcpy\" returns a pointer to the terminating nul character and not to the beginning of the object, the call to \"free\" below is diagnosed. void f (char *p) { p = stpcpy (p, \"abc\"); // ... free (p); // warning } -Wfree-nonheap-object is included in -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if the stack usage of a function might exceed byte-size. The computation done to determine the stack usage is conservative. Any space allocated via \"alloca\", variable- length arrays, or related constructs is included by the compiler when determining whether or not to issue a warning. The message is in keeping with the output of -fstack-usage. * If the stack usage is fully static but exceeds the specified amount, it's: warning: stack usage is 1120 bytes * If the stack usage is (partly) dynamic but bounded, it's: warning: stack usage might be 1648 bytes * If the stack usage is (partly) dynamic and not bounded, it's: warning: stack usage might be unbounded -Wstack-usage=PTRDIFFMAX is enabled by default. Warnings controlled by the option can be disabled either by specifying byte-size of SIZEMAX or more or by -Wno-stack-usage."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable -Wstack-usage= warnings. The option is equivalent to -Wstack-usage=SIZEMAX or larger."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if the loop cannot be optimized because the compiler cannot assume anything on the bounds of the loop indices. With -funsafe-loop-optimizations warn if the compiler makes such assumptions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When used in combination with -Wformat and -pedantic without GNU extensions, this option disables the warnings about non-ISO \"printf\" / \"scanf\" format width specifiers \"I32\", \"I64\", and \"I\" used on Windows targets, which depend on the MS runtime."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about anything that depends on the \"size of\" a function type or of \"void\". GNU C assigns these types a size of 1, for convenience in calculations with \"void *\" pointers and pointers to functions. In C++, warn also when an arithmetic operation involves \"NULL\". This warning is also enabled by -Wpedantic."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn if a pointer is compared with a zero character constant. This usually means that the pointer was meant to be dereferenced. For example: const char *p = foo (); if (p == '\\0') return 42; Note that the code above is invalid in C++11. This warning is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about unsupported features in ThreadSanitizer. ThreadSanitizer does not support \"std::atomicthreadfence\" and can report false positives. This warning is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a comparison is always true or always false due to the limited range of the data type, but do not warn for constant expressions. For example, warn if an unsigned variable is compared against zero with \"<\" or \">=\". This warning is also enabled by -Wextra."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for calls to standard functions that compute the absolute value of an argument when a more appropriate standard function is available. For example, calling abs(3.14) triggers the warning because the appropriate function to call to compute the absolute value of a double argument is \"fabs\". The option also triggers warnings when the argument in a call to such a function has an unsigned type. This warning can be suppressed with an explicit type cast and it is also enabled by -Wextra."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a comment-start sequence /* appears in a /* comment, or whenever a backslash-newline appears in a // comment. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if any trigraphs are encountered that might change the meaning of the program. Trigraphs within comments are not warned about, except those that would form escaped newlines. This option is implied by -Wall. If -Wall is not given, this option is still enabled unless trigraphs are enabled. To get trigraph conversion without warnings, but get the other -Wall warnings, use -trigraphs -Wall -Wno-trigraphs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if an undefined identifier is evaluated in an \"#if\" directive. Such identifiers are replaced with zero."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever defined is encountered in the expansion of a macro (including the case where the macro is expanded by an #if directive). Such usage is not portable. This warning is also enabled by -Wpedantic and -Wextra."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about macros defined in the main file that are unused. A macro is used if it is expanded or tested for existence at least once. The preprocessor also warns if the macro has not been used at the time it is redefined or undefined. Built-in macros, macros defined on the command line, and macros defined in include files are not warned about. Note: If a macro is actually used, but only used in skipped conditional blocks, then the preprocessor reports it as unused. To avoid the warning in such a case, you might improve the scope of the macro's definition by, for example, moving it into the first skipped block. Alternatively, you could provide a dummy use with something like: #if defined themacrocausingthewarning #endif"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn whenever an \"#else\" or an \"#endif\" are followed by text. This sometimes happens in older programs with code of the form #if FOO ... #else FOO ... #endif FOO The second and third \"FOO\" should be in comments. This warning is on by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a function call is cast to a non-matching type. For example, warn if a call to a function returning an integer type is cast to a pointer type."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about features not present in ISO C90, but present in ISO C99. For instance, warn about use of variable length arrays, \"long long\" type, \"bool\" type, compound literals, designated initializers, and so on. This option is independent of the standards mode. Warnings are disabled in the expression that follows \"extension\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about features not present in ISO C99, but present in ISO C11. For instance, warn about use of anonymous structures and unions, \"Atomic\" type qualifier, \"Threadlocal\" storage-class specifier, \"Alignas\" specifier, \"Alignof\" operator, \"Generic\" keyword, and so on. This option is independent of the standards mode. Warnings are disabled in the expression that follows \"extension\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about features not present in ISO C11, but present in ISO C2X. For instance, warn about omitting the string in \"Staticassert\", use of [[]] syntax for attributes, use of decimal floating-point types, and so on. This option is independent of the standards mode. Warnings are disabled in the expression that follows \"extension\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about ISO C constructs that are outside of the common subset of ISO C and ISO C++, e.g. request for implicit conversion from \"void *\" to a pointer to non-\"void\" type."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about C++ constructs whose meaning differs between ISO C++ 1998 and ISO C++ 2011, e.g., identifiers in ISO C++ 1998 that are keywords in ISO C++ 2011. This warning turns on -Wnarrowing and is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about C++ constructs whose meaning differs between ISO C++ 2011 and ISO C++ 2014. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about C++ constructs whose meaning differs between ISO C++ 2014 and ISO C++ 2017. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about C++ constructs whose meaning differs between ISO C++ 2017 and ISO C++ 2020. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn about C++11 constructs in code being compiled using an older C++ standard. Even without this option, some C++11 constructs will only be diagnosed if -Wpedantic is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn about C++14 constructs in code being compiled using an older C++ standard. Even without this option, some C++14 constructs will only be diagnosed if -Wpedantic is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn about C++17 constructs in code being compiled using an older C++ standard. Even without this option, some C++17 constructs will only be diagnosed if -Wpedantic is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn about C++20 constructs in code being compiled using an older C++ standard. Even without this option, some C++20 constructs will only be diagnosed if -Wpedantic is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn about C++23 constructs in code being compiled using an older C++ standard. Even without this option, some C++23 constructs will only be diagnosed if -Wpedantic is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a pointer is cast so as to remove a type qualifier from the target type. For example, warn if a \"const char *\" is cast to an ordinary \"char *\". Also warn when making a cast that introduces a type qualifier in an unsafe way. For example, casting \"char \" to \"const char \" is unsafe, as in this example: /* p is char value. */ const char q = (const char ) p; /* Assignment of readonly string to const char * is OK. */ *q = \"string\"; /* Now char pointer points to read-only memory. */ p = 'b';"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a pointer is cast such that the required alignment of the target is increased. For example, warn if a \"char *\" is cast to an \"int *\" on machines where integers can only be accessed at two- or four-byte boundaries."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn whenever a pointer is cast such that the required alignment of the target is increased. For example, warn if a \"char *\" is cast to an \"int *\" regardless of the target machine."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a function pointer is cast to an incompatible function pointer. In a cast involving function types with a variable argument list only the types of initial arguments that are provided are considered. Any parameter of pointer-type matches any other pointer-type. Any benign differences in integral types are ignored, like \"int\" vs. \"long\" on ILP32 targets. Likewise type qualifiers are ignored. The function type \"void (*) (void)\" is special and matches everything, which can be used to suppress this warning. In a cast involving pointer to member types this warning warns whenever the type cast is changing the pointer to member type. This warning is enabled by -Wextra."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When compiling C, give string constants the type \"const char[length]\" so that copying the address of one into a non-\"const\" \"char *\" pointer produces a warning. These warnings help you find at compile time code that can try to write into a string constant, but only if you have been very careful about using \"const\" in declarations and prototypes. Otherwise, it is just a nuisance. This is why we did not make -Wall request these warnings. When compiling C++, warn about the deprecated conversion from string literals to \"char *\". This warning is enabled by default for C++ programs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for variables that might be changed by \"longjmp\" or \"vfork\". This warning is also enabled by -Wextra."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "By default, language front ends complain when a command-line option is valid, but not applicable to that front end. This may be disabled with -Wno-complain-wrong-lang, which is mostly useful when invoking a single compiler driver for multiple source files written in different languages, for example: $ g++ -fno-rtti a.cc b.f90 The driver g++ invokes the C++ front end to compile a.cc and the Fortran front end to compile b.f90. The latter front end diagnoses f951: Warning: command-line option '-fno-rtti' is valid for C++/D/ObjC++ but not for Fortran, which may be disabled with -Wno-complain-wrong-lang."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for implicit conversions that may alter a value. This includes conversions between real and integer, like \"abs (x)\" when \"x\" is \"double\"; conversions between signed and unsigned, like \"unsigned ui = -1\"; and conversions to smaller types, like \"sqrtf (MPI)\". Do not warn for explicit casts like \"abs ((int) x)\" and \"ui = (unsigned) -1\", or if the value is not changed by the conversion like in \"abs (2.0)\". Warnings about conversions between signed and unsigned integers can be disabled by using -Wno-sign-conversion. For C++, also warn for confusing overload resolution for user-defined conversions; and conversions that never use a type conversion operator: conversions to \"void\", the same type, a base class or a reference to them. Warnings about conversions between signed and unsigned integers are disabled by default in C++ unless -Wsign-conversion is explicitly enabled. Warnings about conversion from arithmetic on a small type back to that type are only given with -Warith-conversion."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about constructions where there may be confusion to which \"if\" statement an \"else\" branch belongs. Here is an example of such a case: { if (a) if (b) foo (); else bar (); } In C/C++, every \"else\" branch belongs to the innermost possible \"if\" statement, which in this example is \"if (b)\". This is often not what the programmer expected, as illustrated in the above example by indentation the programmer chose. When there is the potential for this confusion, GCC issues a warning when this flag is specified. To eliminate the warning, add explicit braces around the innermost \"if\" statement so there is no way the \"else\" can belong to the enclosing \"if\". The resulting code looks like this: { if (a) { if (b) foo (); else bar (); } } This warning is enabled by -Wparentheses."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about uses of pointers (or C++ references) to objects with automatic storage duration after their lifetime has ended. This includes local variables declared in nested blocks, compound literals and other unnamed temporary objects. In addition, warn about storing the address of such objects in escaped pointers. The warning is enabled at all optimization levels but may yield different results with optimization than without. -Wdangling-pointer=1 At level 1 the warning diagnoses only unconditional uses of dangling pointers. For example int f (int c1, int c2, x) { char *p = strchr ((char[]){ c1, c2 }, c3); // warning: dangling pointer to a compound literal return p ? *p : 'x'; } In the following function the store of the address of the local variable \"x\" in the escaped pointer *p also triggers the warning. void g (int p) { int x = 7; // warning: storing the address of a local variable in *p *p = &x; } -Wdangling-pointer=2 At level 2, in addition to unconditional uses the warning also diagnoses conditional uses of dangling pointers. For example, because the array a in the following function is out of scope when the pointer s that was set to point is used, the warning triggers at this level. void f (char *s) { if (!s) { char a[12] = \"tmpname\"; s = a; } // warning: dangling pointer to a may be used strcat (s, \".tmp\"); ... } -Wdangling-pointer=2 is included in -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when macros \"TIME\", \"DATE\" or \"TIMESTAMP\" are encountered as they might prevent bit-wise-identical reproducible compilations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if an empty body occurs in an \"if\", \"else\" or \"do while\" statement. This warning is also enabled by -Wextra."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn about stray tokens after \"#else\" and \"#endif\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about a comparison between values of different enumerated types. In C++ enumerated type mismatches in conditional expressions are also diagnosed and the warning is enabled by default. In C this warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a value of enumerated type is implicitly converted to a different enumerated type. This warning is enabled by -Wextra in C."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about mismatches between an enumerated type and an integer type in declarations. For example: enum E { l = -1, z = 0, g = 1 }; int foo(void); enum E foo(void); In C, an enumerated type is compatible with \"char\", a signed integer type, or an unsigned integer type. However, since the choice of the underlying type of an enumerated type is implementation-defined, such mismatches may cause portability issues. In C++, such mismatches are an error. In C, this warning is enabled by -Wall and -Wc++-compat."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a \"goto\" statement or a \"switch\" statement jumps forward across the initialization of a variable, or jumps backward to a label after the variable has been initialized. This only warns about variables that are initialized when they are declared. This warning is only supported for C and Objective-C; in C++ this sort of branch is an error in any case. -Wjump-misses-init is included in -Wc++-compat. It can be disabled with the -Wno-jump-misses-init option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when a comparison between signed and unsigned values could produce an incorrect result when the signed value is converted to unsigned. In C++, this warning is also enabled by -Wall. In C, it is also enabled by -Wextra."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for implicit conversions that may change the sign of an integer value, like assigning a signed integer expression to an unsigned integer variable. An explicit cast silences the warning. In C, this option is enabled also by -Wconversion."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for implicit conversions that reduce the precision of a real value. This includes conversions from real to integer, and from higher precision real to lower precision real values. This option is also enabled by -Wconversion."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn on suspicious constructs involving reverse scalar storage order."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about divisions of two sizeof operators when the first one is applied to an array and the divisor does not equal the size of the array element. In such a case, the computation will not yield the number of elements in the array, which is likely what the user intended. This warning warns e.g. about int fn () { int arr[10]; return sizeof (arr) / sizeof (short); } This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for suspicious divisions of two sizeof expressions that divide the pointer size by the element size, which is the usual way to compute the array size but won't work out correctly with pointers. This warning warns e.g. about \"sizeof (ptr) / sizeof (ptr[0])\" if \"ptr\" is not an array, but a pointer. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for suspicious length parameters to certain string and memory built-in functions if the argument uses \"sizeof\". This warning triggers for example for \"memset (ptr, 0, sizeof (ptr));\" if \"ptr\" is not an array, but a pointer, and suggests a possible fix, or about \"memcpy (&foo, ptr, sizeof (&foo));\". -Wsizeof-pointer-memaccess also warns about calls to bounded string copy functions like \"strncat\" or \"strncpy\" that specify as the bound a \"sizeof\" expression of the source array. For example, in the following function the call to \"strncat\" specifies the size of the source string as the bound. That is almost certainly a mistake and so the call is diagnosed. void makefile (const char *name) { char path[PATHMAX]; strncpy (path, name, sizeof path - 1); strncat (path, \".text\", sizeof \".text\"); ... } The -Wsizeof-pointer-memaccess option is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn when the \"sizeof\" operator is applied to a parameter that is declared as an array in a function definition. This warning is enabled by default for C and C++ programs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for suspicious calls to the \"memset\" built-in function, if the first argument references an array, and the third argument is a number equal to the number of elements, but not equal to the size of the array in memory. This indicates that the user has omitted a multiplication by the element size. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for suspicious calls to the \"memset\" built-in function where the second argument is not zero and the third argument is zero. For example, the call \"memset (buf, sizeof buf, 0)\" is diagnosed because \"memset (buf, 0, sizeof buf)\" was meant instead. The diagnostic is only emitted if the third argument is a literal zero. Otherwise, if it is an expression that is folded to zero, or a cast of zero to some type, it is far less likely that the arguments have been mistakenly transposed and no warning is emitted. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about suspicious uses of address expressions. These include comparing the address of a function or a declared object to the null pointer constant such as in void f (void); void g (void) { if (!f) // warning: expression evaluates to false abort (); } comparisons of a pointer to a string literal, such as in void f (const char *x) { if (x == \"abc\") // warning: expression evaluates to false puts (\"equal\"); } and tests of the results of pointer addition or subtraction for equality to null, such as in void f (const int *p, int i) { return p + i == NULL; } Such uses typically indicate a programmer error: the address of most functions and objects necessarily evaluates to true (the exception are weak symbols), so their use in a conditional might indicate missing parentheses in a function call or a missing dereference in an array expression. The subset of the warning for object pointers can be suppressed by casting the pointer operand to an integer type such as \"intptrt\" or \"uintptrt\". Comparisons against string literals result in unspecified behavior and are not portable, and suggest the intent was to call \"strcmp\". The warning is suppressed if the suspicious expression is the result of macro expansion. -Waddress warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn when the address of packed member of struct or union is taken, which usually results in an unaligned pointer value. This is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about suspicious uses of logical operators in expressions. This includes using logical operators in contexts where a bit-wise operator is likely to be expected. Also warns when the operands of a logical operator are the same: extern int a; if (a < 0 && a < 0) { ... }"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about logical not used on the left hand side operand of a comparison. This option does not warn if the right operand is considered to be a boolean expression. Its purpose is to detect suspicious code like the following: int a; ... if (!a > 1) { ... } It is possible to suppress the warning by wrapping the LHS into parentheses: if ((!a) > 1) { ... } This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if any functions that return structures or unions are defined or called. (In languages where you can return an array, this also elicits a warning.)"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if in a loop with constant number of iterations the compiler detects undefined behavior in some statement during one or more of the iterations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn if an unexpected \"attribute\" is used, such as unrecognized attributes, function attributes applied to variables, etc. This does not stop errors for incorrect use of supported attributes. Additionally, using -Wno-attributes=, it is possible to suppress warnings about unknown scoped attributes (in C++11 and C2X). For example, -Wno-attributes=vendor::attr disables warning about the following declaration: [[vendor::attr]] void f(); It is also possible to disable warning about all attributes in a namespace using -Wno-attributes=vendor:: which prevents warning about both of these declarations: [[vendor::safe]] void f(); [[vendor::unsafe]] void f2(); Note that -Wno-attributes= does not imply -Wno-attributes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a built-in function is declared with an incompatible signature or as a non- function, or when a built-in function declared with a type that does not include a prototype is called with arguments whose promoted types do not match those expected by the function. When -Wextra is specified, also warn when a built-in function that takes arguments is declared without a prototype. The -Wbuiltin-declaration-mismatch warning is enabled by default. To avoid the warning include the appropriate header to bring the prototypes of built-in functions into scope. For example, the call to \"memset\" below is diagnosed by the warning because the function expects a value of type \"sizet\" as its argument but the type of 32 is \"int\". With -Wextra, the declaration of the function is diagnosed as well. extern void* memset (); void f (void *d) { memset (d, '\\0', 32); }"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn if certain built-in macros are redefined. This suppresses warnings for redefinition of \"TIMESTAMP\", \"TIME\", \"DATE\", \"FILE\", and \"BASEFILE\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a function is declared or defined without specifying the argument types. (An old-style function definition is permitted without a warning if preceded by a declaration that specifies the argument types.)"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for obsolescent usages, according to the C Standard, in a declaration. For example, warn if storage-class specifiers like \"static\" are not the first things in a declaration. This warning is also enabled by -Wextra."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if an old-style function definition is used. A warning is given even if there is a previous prototype. A definition using () is not considered an old-style definition in C2X mode, because it is equivalent to (void) in that case, but is considered an old-style definition for older standards."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "A function parameter is declared without a type specifier in K&R-style functions: void foo(bar) { } This warning is also enabled by -Wextra."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a global function is defined without a previous prototype declaration. This warning is issued even if the definition itself provides a prototype. Use this option to detect global functions that do not have a matching prototype declaration in a header file. This option is not valid for C++ because all function declarations provide prototypes and a non-matching declaration declares an overload rather than conflict with an earlier declaration. Use -Wmissing-declarations to detect missing declarations in C++."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a global function is defined without a previous declaration. Do so even if the definition itself provides a prototype. Use this option to detect global functions that are not declared in header files. In C, no warnings are issued for functions with previous non-prototype declarations; use -Wmissing-prototypes to detect missing prototypes. In C++, no warnings are issued for function templates, or for inline functions, or for functions in anonymous namespaces."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a structure's initializer has some fields missing. For example, the following code causes such a warning, because \"x.h\" is implicitly zero: struct s { int f, g, h; }; struct s x = { 3, 4 }; This option does not warn about designated initializers, so the following modification does not trigger a warning: struct s { int f, g, h; }; struct s x = { .f = 3, .g = 4 }; In C this option does not warn about the universal zero initializer { 0 }: struct s { int f, g, h; }; struct s x = { 0 }; Likewise, in C++ this option does not warn about the empty { } initializer, for example: struct s { int f, g, h; }; s x = { }; This warning is included in -Wextra. To get other -Wextra warnings without this one, use -Wextra -Wno-missing-field-initializers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "By default, the compiler warns about a concept-id appearing as a C++20 simple- requirement: bool satisfied = requires { C<T> }; Here satisfied will be true if C<T> is a valid expression, which it is for all T. Presumably the user meant to write bool satisfied = requires { requires C<T> }; so satisfied is only true if concept C is satisfied for type T. This warning can be disabled with -Wno-missing-requires."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The member access tokens ., -> and :: must be followed by the \"template\" keyword if the parent object is dependent and the member being named is a template. template <class X> void DoStuff (X x) { x.template DoSomeOtherStuff<X>(); // Good. x.DoMoreStuff<X>(); // Warning, x is dependent. } In rare cases it is possible to get false positives. To silence this, wrap the expression in parentheses. For example, the following is treated as a template, even where m and N are integers: void NotATemplate (myclass t) { int N = 5; bool test = t.m < N > (0); // Treated as a template. test = (t.m < N) > (0); // Same meaning, but not treated as a template. } This warning can be disabled with -Wno-missing-template-keyword."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn if a multicharacter constant ('FOOF') is used. Usually they indicate a typo in the user's code, as they have implementation-defined values, and should not be used in portable code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "In ISO C and ISO C++, two identifiers are different if they are different sequences of characters. However, sometimes when characters outside the basic ASCII character set are used, you can have two different character sequences that look the same. To avoid confusion, the ISO 10646 standard sets out some normalization rules which when applied ensure that two sequences that look the same are turned into the same sequence. GCC can warn you if you are using identifiers that have not been normalized; this option controls that warning. There are four levels of warning supported by GCC. The default is -Wnormalized=nfc, which warns about any identifier that is not in the ISO 10646 \"C\" normalized form, NFC. NFC is the recommended form for most uses. It is equivalent to -Wnormalized. Unfortunately, there are some characters allowed in identifiers by ISO C and ISO C++ that, when turned into NFC, are not allowed in identifiers. That is, there's no way to use these symbols in portable ISO C or C++ and have all your identifiers in NFC. -Wnormalized=id suppresses the warning for these characters. It is hoped that future versions of the standards involved will correct this, which is why this option is not the default. You can switch the warning off for all characters by writing -Wnormalized=none or -Wno-normalized. You should only do this if you are using some other normalization scheme (like \"D\"), because otherwise you can easily create bugs that are literally impossible to see. Some characters in ISO 10646 have distinct meanings but look identical in some fonts or display methodologies, especially once formatting has been applied. For instance \"\\u207F\", \"SUPERSCRIPT LATIN SMALL LETTER N\", displays just like a regular \"n\" that has been placed in a superscript. ISO 10646 defines the NFKC normalization scheme to convert all these into a standard form as well, and GCC warns if your code is not in NFKC if you use -Wnormalized=nfkc. This warning is comparable to warning about every identifier that contains the letter O because it might be confused with the digit 0, and so is not the default, but may be useful as a local coding convention if the programming environment cannot be fixed to display these characters distinctly."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn about usage of functions declared with \"warning\" attribute. By default, this warning is enabled. -Wno-attribute-warning can be used to disable the warning or -Wno-error=attribute-warning can be used to disable the error when compiled with -Werror flag."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn about usage of deprecated features."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn about uses of functions, variables, and types marked as deprecated by using the \"deprecated\" attribute."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn about compile-time overflow in constant expressions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about One Definition Rule violations during link-time optimization. Enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about potentially suboptimal choices related to OpenACC parallelism."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if the vectorizer cost model overrides the OpenMP simd directive set by user. The -fsimd-cost-model=unlimited option can be used to relax the cost model."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if an initialized field without side effects is overridden when using designated initializers. This warning is included in -Wextra. To get other -Wextra warnings without this one, use -Wextra -Wno-override-init."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn if an initialized field with side effects is overridden when using designated initializers. This warning is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a structure is given the packed attribute, but the packed attribute has no effect on the layout or size of the structure. Such structures may be mis-aligned for little benefit. For instance, in this code, the variable \"f.x\" in \"struct bar\" is misaligned even though \"struct bar\" does not itself have the packed attribute: struct foo { int x; char a, b, c, d; } attribute((packed)); struct bar { char z; struct foo f; };"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The 4.1, 4.2 and 4.3 series of GCC ignore the \"packed\" attribute on bit-fields of type \"char\". This was fixed in GCC 4.4 but the change can lead to differences in the structure layout. GCC informs you when the offset of such a field has changed in GCC 4.4. For example there is no longer a 4-bit padding between field \"a\" and \"b\" in this structure: struct foo { char a:4; char b:8; } attribute ((packed)); This warning is enabled by default. Use -Wno-packed-bitfield-compat to disable this warning."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a structure field with explicitly specified alignment in a packed struct or union is misaligned. For example, a warning will be issued on \"struct S\", like, \"warning: alignment 1 of 'struct S' is less than 8\", in this code: struct attribute ((aligned (8))) S8 { char a[8]; }; struct attribute ((packed)) S { struct S8 s8; }; This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if padding is included in a structure, either to align an element of the structure or to align the whole structure. Sometimes when this happens it is possible to rearrange the fields of the structure to reduce the padding and so make the structure smaller."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if anything is declared more than once in the same scope, even in cases where multiple declaration is valid and changes nothing."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when an object referenced by a \"restrict\"-qualified parameter (or, in C++, a \"restrict\"-qualified parameter) is aliased by another argument, or when copies between such objects overlap. For example, the call to the \"strcpy\" function below attempts to truncate the string by replacing its initial characters with the last four. However, because the call writes the terminating NUL into \"a[4]\", the copies overlap and the call is diagnosed. void foo (void) { char a[] = \"abcd1234\"; strcpy (a, a + 4); ... } The -Wrestrict option detects some instances of simple overlap even without optimization but works best at -O2 and above. It is included in -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if an \"extern\" declaration is encountered within a function."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a function that is declared as inline cannot be inlined. Even with this option, the compiler does not warn about failures to inline functions declared in system headers. The compiler uses a variety of heuristics to determine whether or not to inline a function. For example, the compiler takes into account the size of the function being inlined and the amount of inlining that has already been done in the current function. Therefore, seemingly insignificant changes in the source program can cause the warnings produced by -Winline to appear or disappear."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about use of C++17 \"std::hardwaredestructiveinterferencesize\" without specifying its value with --param destructive-interference-size. Also warn about questionable values for that option. This variable is intended to be used for controlling class layout, to avoid false sharing in concurrent code: struct independentfields { alignas(std::hardwaredestructiveinterferencesize) std::atomic<int> one; alignas(std::hardwaredestructiveinterferencesize) std::atomic<int> two; }; Here one and two are intended to be far enough apart that stores to one won't require accesses to the other to reload the cache line. By default, --param destructive-interference-size and --param constructive-interference- size are set based on the current -mtune option, typically to the L1 cache line size for the particular target CPU, sometimes to a range if tuning for a generic target. So all translation units that depend on ABI compatibility for the use of these variables must be compiled with the same -mtune (or -mcpu). If ABI stability is important, such as if the use is in a header for a library, you should probably not use the hardware interference size variables at all. Alternatively, you can force a particular value with --param. If you are confident that your use of the variable does not affect ABI outside a single build of your project, you can turn off the warning with -Wno-interference-size."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for suspicious use of integer values where boolean values are expected, such as conditional expressions (?:) using non-boolean integer constants in boolean context, like \"if (a <= b ? 2 : 3)\". Or left shifting of signed integers in boolean context, like \"for (a = 0; 1 << a; a++);\". Likewise for all kinds of multiplications regardless of the data type. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Suppress warnings from casts to pointer type of an integer of a different size. In C++, casting to a pointer type of smaller size is an error. Wint-to-pointer-cast is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Suppress warnings from casts from a pointer to an integer type of a different size."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a precompiled header is found in the search path but cannot be used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if an invalid UTF-8 character is found. This warning is on by default for C++23 if -finput-charset=UTF-8 is used and turned into error with -pedantic-errors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't diagnose invalid forms of delimited or named escape sequences which are treated as separate tokens. Wunicode is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if \"long long\" type is used. This is enabled by either -Wpedantic or -Wtraditional in ISO C90 and C++98 modes. To inhibit the warning messages, use -Wno-long-long."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if variadic macros are used in ISO C90 mode, or if the GNU alternate syntax is used in ISO C99 mode. This is enabled by either -Wpedantic or -Wtraditional. To inhibit the warning messages, use -Wno-variadic-macros."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not warn upon questionable usage of the macros used to handle variable arguments like \"vastart\". These warnings are enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if vector operation is not implemented via SIMD capabilities of the architecture. Mainly useful for the performance tuning. Vector operation can be implemented \"piecewise\", which means that the scalar operation is performed on every vector element; \"in parallel\", which means that the vector operation is implemented using scalars of wider type, which normally is more performance efficient; and \"as a single scalar\", which means that vector fits into a scalar type."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a variable-length array is used in the code. -Wno-vla prevents the -Wpedantic warning of the variable-length array."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If this option is used, the compiler warns for declarations of variable-length arrays whose size is either unbounded, or bounded by an argument that allows the array size to exceed byte-size bytes. This is similar to how -Walloca-larger-than=byte-size works, but with variable-length arrays. Note that GCC may optimize small variable-length arrays of a known value into plain arrays, so this warning may not get triggered for such arrays. -Wvla-larger-than=PTRDIFFMAX is enabled by default but is typically only effective when -ftree-vrp is active (default for -O2 and above). See also -Walloca-larger-than=byte-size."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable -Wvla-larger-than= warnings. The option is equivalent to -Wvla-larger-than=SIZEMAX or larger."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about redeclarations of functions involving arguments of Variable Length Array types of inconsistent kinds or forms, and enable the detection of out-of-bounds accesses to such parameters by warnings such as -Warray-bounds. If the first function declaration uses the VLA form the bound specified in the array is assumed to be the minimum number of elements expected to be provided in calls to the function and the maximum number of elements accessed by it. Failing to provide arguments of sufficient size or accessing more than the maximum number of elements may be diagnosed. For example, the warning triggers for the following redeclarations because the first one allows an array of any size to be passed to \"f\" while the second one specifies that the array argument must have at least \"n\" elements. In addition, calling \"f\" with the associated VLA bound parameter in excess of the actual VLA bound triggers a warning as well. void f (int n, int[n]); // warning: argument 2 previously declared as a VLA void f (int, int[]); void g (int n) { if (n > 4) return; int a[n]; // warning: access to a by f may be out of bounds f (sizeof a, a); ... } -Wvla-parameter is included in -Wall. The -Warray-parameter option triggers warnings for similar problems involving ordinary array arguments."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a register variable is declared volatile. The volatile modifier does not inhibit all optimizations that may eliminate reads and/or writes to register variables. This warning is enabled by -Wall."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about uses of \"^\", the exclusive or operator, where it appears the user meant exponentiation. Specifically, the warning occurs when the left-hand side is the decimal constant 2 or 10 and the right-hand side is also a decimal constant. In C and C++, \"^\" means exclusive or, whereas in some other languages (e.g. TeX and some versions of BASIC) it means exponentiation. This warning is enabled by default. It can be silenced by converting one of the operands to hexadecimal."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if a requested optimization pass is disabled. This warning does not generally indicate that there is anything wrong with your code; it merely indicates that GCC's optimizers are unable to handle the code effectively. Often, the problem is that your code is too big or too complex; GCC refuses to optimize programs when the optimization itself is likely to take inordinate amounts of time."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn for pointer argument passing or assignment with different signedness. This option is only supported for C and Objective-C. It is implied by -Wall and by -Wpedantic, which can be disabled with -Wno-pointer-sign."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is only active when -fstack-protector is active. It warns about functions that are not protected against stack smashing."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about string constants that are longer than the \"minimum maximum\" length specified in the C standard. Modern compilers generally allow string constants that are much longer than the standard's minimum limit, but very portable programs should avoid using longer strings. The limit applies after string constant concatenation, and does not count the trailing NUL. In C90, the limit was 509 characters; in C99, it was raised to 4095. C++98 does not specify a normative minimum maximum, so we do not diagnose overlength strings in C++. This option is implied by -Wpedantic, and can be disabled with -Wno-overlength-strings."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Issue a warning for any floating constant that does not have a suffix. When used together with -Wsystem-headers it warns about such constants in system header files. This can be useful when preparing code to use with the \"FLOATCONSTDECIMAL64\" pragma from the decimal floating-point extension to C99."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "During the link-time optimization, do not warn about type mismatches in global declarations from different compilation units. Requires -flto to be enabled. Enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Suppress warnings when a positional initializer is used to initialize a structure that has been marked with the \"designatedinit\" attribute."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option enables an static analysis of program flow which looks for \"interesting\" interprocedural paths through the code, and issues warnings for problems found on them. This analysis is much more expensive than other GCC warnings. In technical terms, it performs coverage-guided symbolic execution of the code being compiled. It is neither sound nor complete: it can have false positives and false negatives. It is a bug-finding tool, rather than a tool for proving program correctness. The analyzer is only suitable for use on C code in this release. Enabling this option effectively enables the following warnings: -Wanalyzer-allocation-size -Wanalyzer-deref-before-check -Wanalyzer-double-fclose -Wanalyzer-double-free -Wanalyzer-exposure-through-output-file -Wanalyzer-exposure-through-uninit-copy -Wanalyzer-fd-access-mode-mismatch -Wanalyzer-fd-double-close -Wanalyzer-fd-leak -Wanalyzer-fd-phase-mismatch -Wanalyzer-fd-type-mismatch -Wanalyzer-fd-use-after-close -Wanalyzer-fd-use-without-check -Wanalyzer-file-leak -Wanalyzer-free-of-non-heap -Wanalyzer-imprecise-fp-arithmetic -Wanalyzer-infinite-recursion -Wanalyzer-jump-through-null -Wanalyzer-malloc-leak -Wanalyzer-mismatching-deallocation -Wanalyzer-null-argument -Wanalyzer-null-dereference -Wanalyzer-out-of-bounds -Wanalyzer-possible-null-argument -Wanalyzer-possible-null-dereference -Wanalyzer-putenv-of-auto-var -Wanalyzer-shift-count-negative -Wanalyzer-shift-count-overflow -Wanalyzer-stale-setjmp-buffer -Wanalyzer-unsafe-call-within-signal-handler -Wanalyzer-use-after-free -Wanalyzer-use-of-pointer-in-stale-stack-frame -Wanalyzer-use-of-uninitialized-value -Wanalyzer-va-arg-type-mismatch -Wanalyzer-va-list-exhausted -Wanalyzer-va-list-leak -Wanalyzer-va-list-use-after-va-end -Wanalyzer-write-to-const -Wanalyzer-write-to-string-literal This option is only available if GCC was configured with analyzer support enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If -fanalyzer is enabled, the analyzer uses various heuristics to attempt to explore the control flow and data flow in the program, but these can be defeated by sufficiently complicated code. By default, the analysis silently stops if the code is too complicated for the analyzer to fully explore and it reaches an internal limit. The -Wanalyzer-too-complex option warns if this occurs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; to disable it, use -Wno-analyzer-allocation-size. This diagnostic warns for paths through the code in which a pointer to a buffer is assigned to point at a buffer with a size that is not a multiple of \"sizeof (*pointer)\". See CWE-131: Incorrect Calculation of Buffer Size (\"https://cwe.mitre.org/data/definitions/131.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-deref-before-check to disable it. This diagnostic warns for paths through the code in which a pointer is checked for \"NULL\" *after* it has already been dereferenced, suggesting that the pointer could have been NULL. Such cases suggest that the check for NULL is either redundant, or that it needs to be moved to before the pointer is dereferenced. This diagnostic also considers values passed to a function argument marked with \"attribute((nonnull))\" as requiring a non-NULL value, and thus will complain if such values are checked for \"NULL\" after returning from such a function call. This diagnostic is unlikely to be reported when any level of optimization is enabled, as GCC's optimization logic will typically consider such checks for NULL as being redundant, and optimize them away before the analyzer \"sees\" them. Hence optimization should be disabled when attempting to trigger this diagnostic."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-double-fclose to disable it. This diagnostic warns for paths through the code in which a \"FILE *\" can have \"fclose\" called on it more than once. See CWE-1341: Multiple Releases of Same Resource or Handle (\"https://cwe.mitre.org/data/definitions/1341.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-double-free to disable it. This diagnostic warns for paths through the code in which a pointer can have a deallocator called on it more than once, either \"free\", or a deallocator referenced by attribute \"malloc\". See CWE-415: Double Free (\"https://cwe.mitre.org/data/definitions/415.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-exposure-through-output-file to disable it. This diagnostic warns for paths through the code in which a security-sensitive value is written to an output file (such as writing a password to a log file). See CWE-532: Information Exposure Through Log Files (\"https://cwe.mitre.org/data/definitions/532.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires both -fanalyzer and the use of a plugin to specify a function that copies across a \"trust boundary\". Use -Wno-analyzer-exposure-through-uninit-copy to disable it. This diagnostic warns for \"infoleaks\" - paths through the code in which uninitialized values are copied across a security boundary (such as code within an OS kernel that copies a partially-initialized struct on the stack to user space). See CWE-200: Exposure of Sensitive Information to an Unauthorized Actor (\"https://cwe.mitre.org/data/definitions/200.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-fd-access-mode-mismatch to disable it. This diagnostic warns for paths through code in which a \"read\" on a write-only file descriptor is attempted, or vice versa. This diagnostic also warns for code paths in a which a function with attribute \"fdargread (N)\" is called with a file descriptor opened with \"OWRONLY\" at referenced argument \"N\" or a function with attribute \"fdargwrite (N)\" is called with a file descriptor opened with \"ORDONLY\" at referenced argument N."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-fd-double-close to disable it. This diagnostic warns for paths through code in which a file descriptor can be closed more than once. See CWE-1341: Multiple Releases of Same Resource or Handle (\"https://cwe.mitre.org/data/definitions/1341.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-fd-leak to disable it. This diagnostic warns for paths through code in which an open file descriptor is leaked. See CWE-775: Missing Release of File Descriptor or Handle after Effective Lifetime (\"https://cwe.mitre.org/data/definitions/775.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-fd-phase-mismatch to disable it. This diagnostic warns for paths through code in which an operation is attempted in the wrong phase of a file descriptor's lifetime. For example, it will warn on attempts to call \"accept\" on a stream socket that has not yet had \"listen\" successfully called on it. See CWE-666: Operation on Resource in Wrong Phase of Lifetime (\"https://cwe.mitre.org/data/definitions/666.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-fd-type-mismatch to disable it. This diagnostic warns for paths through code in which an operation is attempted on the wrong type of file descriptor. For example, it will warn on attempts to use socket operations on a file descriptor obtained via \"open\", or when attempting to use a stream socket operation on a datagram socket."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-fd-use-after-close to disable it. This diagnostic warns for paths through code in which a read or write is called on a closed file descriptor. This diagnostic also warns for paths through code in which a function with attribute \"fdarg (N)\" or \"fdargread (N)\" or \"fdargwrite (N)\" is called with a closed file descriptor at referenced argument \"N\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-fd-use-without-check to disable it. This diagnostic warns for paths through code in which a file descriptor is used without being checked for validity. This diagnostic also warns for paths through code in which a function with attribute \"fdarg (N)\" or \"fdargread (N)\" or \"fdargwrite (N)\" is called with a file descriptor, at referenced argument \"N\", without being checked for validity."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-file-leak to disable it. This diagnostic warns for paths through the code in which a \"<stdio.h>\" \"FILE *\" stream object is leaked. See CWE-775: Missing Release of File Descriptor or Handle after Effective Lifetime (\"https://cwe.mitre.org/data/definitions/775.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-free-of-non-heap to disable it. This diagnostic warns for paths through the code in which \"free\" is called on a non-heap pointer (e.g. an on-stack buffer, or a global). See CWE-590: Free of Memory not on the Heap (\"https://cwe.mitre.org/data/definitions/590.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-imprecise-fp-arithmetic to disable it. This diagnostic warns for paths through the code in which floating-point arithmetic is used in locations where precise computation is needed. This diagnostic only warns on use of floating-point operands inside the calculation of an allocation size at the moment."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-infinite-recursion to disable it. This diagnostics warns for paths through the code which appear to lead to infinite recursion. Specifically, when the analyzer \"sees\" a recursive call, it will compare the state of memory at the entry to the new frame with that at the entry to the previous frame of that function on the stack. The warning is issued if nothing in memory appears to be changing; any changes observed to parameters or globals are assumed to lead to termination of the recursion and thus suppress the warning. This diagnostic is likely to miss cases of infinite recursion that are convered to iteration by the optimizer before the analyzer \"sees\" them. Hence optimization should be disabled when attempting to trigger this diagnostic. Compare with -Winfinite-recursion, which provides a similar diagnostic, but is implemented in a different way."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-jump-through-null to disable it. This diagnostic warns for paths through the code in which a \"NULL\" function pointer is called."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-malloc-leak to disable it. This diagnostic warns for paths through the code in which a pointer allocated via an allocator is leaked: either \"malloc\", or a function marked with attribute \"malloc\". See CWE-401: Missing Release of Memory after Effective Lifetime (\"https://cwe.mitre.org/data/definitions/401.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-mismatching-deallocation to disable it. This diagnostic warns for paths through the code in which the wrong deallocation function is called on a pointer value, based on which function was used to allocate the pointer value. The diagnostic will warn about mismatches between \"free\", scalar \"delete\" and vector \"delete[]\", and those marked as allocator/deallocator pairs using attribute \"malloc\". See CWE-762: Mismatched Memory Management Routines (\"https://cwe.mitre.org/data/definitions/762.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-out-of-bounds to disable it. This diagnostic warns for paths through the code in which a buffer is definitely read or written out-of-bounds. The diagnostic applies for cases where the analyzer is able to determine a constant offset and for accesses past the end of a buffer, also a constant capacity. Further, the diagnostic does limited checking for accesses past the end when the offset as well as the capacity is symbolic. See CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer (\"https://cwe.mitre.org/data/definitions/119.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-possible-null-argument to disable it. This diagnostic warns for paths through the code in which a possibly-NULL value is passed to a function argument marked with \"attribute((nonnull))\" as requiring a non-NULL value. See CWE-690: Unchecked Return Value to NULL Pointer Dereference (\"https://cwe.mitre.org/data/definitions/690.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-possible-null-dereference to disable it. This diagnostic warns for paths through the code in which a possibly-NULL value is dereferenced. See CWE-690: Unchecked Return Value to NULL Pointer Dereference (\"https://cwe.mitre.org/data/definitions/690.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-null-argument to disable it. This diagnostic warns for paths through the code in which a value known to be NULL is passed to a function argument marked with \"attribute((nonnull))\" as requiring a non- NULL value. See CWE-476: NULL Pointer Dereference (\"https://cwe.mitre.org/data/definitions/476.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-null-dereference to disable it. This diagnostic warns for paths through the code in which a value known to be NULL is dereferenced. See CWE-476: NULL Pointer Dereference (\"https://cwe.mitre.org/data/definitions/476.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-putenv-of-auto-var to disable it. This diagnostic warns for paths through the code in which a call to \"putenv\" is passed a pointer to an automatic variable or an on-stack buffer. See POS34-C. Do not call putenv() with a pointer to an automatic variable as the argument (\"https://wiki.sei.cmu.edu/confluence/x/6NYxBQ\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-shift-count-negative to disable it. This diagnostic warns for paths through the code in which a shift is attempted with a negative count. It is analogous to the -Wshift-count-negative diagnostic implemented in the C/C++ front ends, but is implemented based on analyzing interprocedural paths, rather than merely parsing the syntax tree. However, the analyzer does not prioritize detection of such paths, so false negatives are more likely relative to other warnings."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-shift-count-overflow to disable it. This diagnostic warns for paths through the code in which a shift is attempted with a count greater than or equal to the precision of the operand's type. It is analogous to the -Wshift-count-overflow diagnostic implemented in the C/C++ front ends, but is implemented based on analyzing interprocedural paths, rather than merely parsing the syntax tree. However, the analyzer does not prioritize detection of such paths, so false negatives are more likely relative to other warnings."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-stale-setjmp-buffer to disable it. This diagnostic warns for paths through the code in which \"longjmp\" is called to rewind to a \"jmpbuf\" relating to a \"setjmp\" call in a function that has returned. When \"setjmp\" is called on a \"jmpbuf\" to record a rewind location, it records the stack frame. The stack frame becomes invalid when the function containing the \"setjmp\" call returns. Attempting to rewind to it via \"longjmp\" would reference a stack frame that no longer exists, and likely lead to a crash (or worse)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires both -fanalyzer and -fanalyzer-checker=taint to enable it; use -Wno-analyzer-tainted-allocation-size to disable it. This diagnostic warns for paths through the code in which a value that could be under an attacker's control is used as the size of an allocation without being sanitized, so that an attacker could inject an excessively large allocation and potentially cause a denial of service attack. See CWE-789: Memory Allocation with Excessive Size Value (\"https://cwe.mitre.org/data/definitions/789.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires both -fanalyzer and -fanalyzer-checker=taint to enable it; use -Wno-analyzer-tainted-assertion to disable it. This diagnostic warns for paths through the code in which a value that could be under an attacker's control is used as part of a condition without being first sanitized, and that condition guards a call to a function marked with attribute \"noreturn\" (such as the function \"builtinunreachable\"). Such functions typically indicate abnormal termination of the program, such as for assertion failure handlers. For example: assert (sometaintedvalue < SOMELIMIT); In such cases: * when assertion-checking is enabled: an attacker could trigger a denial of service by injecting an assertion failure * when assertion-checking is disabled, such as by defining \"NDEBUG\", an attacker could inject data that subverts the process, since it presumably violates a precondition that is being assumed by the code. Note that when assertion-checking is disabled, the assertions are typically removed by the preprocessor before the analyzer has a chance to \"see\" them, so this diagnostic can only generate warnings on builds in which assertion-checking is enabled. For the purpose of this warning, any function marked with attribute \"noreturn\" is considered as a possible assertion failure handler, including \"builtinunreachable\". Note that these functions are sometimes removed by the optimizer before the analyzer \"sees\" them. Hence optimization should be disabled when attempting to trigger this diagnostic. See CWE-617: Reachable Assertion (\"https://cwe.mitre.org/data/definitions/617.html\"). The warning can also report problematic constructions such as switch (sometaintedvalue) { case 0: /* [...etc; various valid cases omitted...] */ break; default: builtinunreachable (); /* BUG: attacker can trigger this */ } despite the above not being an assertion failure, strictly speaking."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires both -fanalyzer and -fanalyzer-checker=taint to enable it; use -Wno-analyzer-tainted-array-index to disable it. This diagnostic warns for paths through the code in which a value that could be under an attacker's control is used as the index of an array access without being sanitized, so that an attacker could inject an out-of-bounds access. See CWE-129: Improper Validation of Array Index (\"https://cwe.mitre.org/data/definitions/129.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires both -fanalyzer and -fanalyzer-checker=taint to enable it; use -Wno-analyzer-tainted-divisor to disable it. This diagnostic warns for paths through the code in which a value that could be under an attacker's control is used as the divisor in a division or modulus operation without being sanitized, so that an attacker could inject a division-by-zero. See CWE-369: Divide By Zero (\"https://cwe.mitre.org/data/definitions/369.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires both -fanalyzer and -fanalyzer-checker=taint to enable it; use -Wno-analyzer-tainted-offset to disable it. This diagnostic warns for paths through the code in which a value that could be under an attacker's control is used as a pointer offset without being sanitized, so that an attacker could inject an out-of-bounds access. See CWE-823: Use of Out-of-range Pointer Offset (\"https://cwe.mitre.org/data/definitions/823.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires both -fanalyzer and -fanalyzer-checker=taint to enable it; use -Wno-analyzer-tainted-size to disable it. This diagnostic warns for paths through the code in which a value that could be under an attacker's control is used as the size of an operation such as \"memset\" without being sanitized, so that an attacker could inject an out-of-bounds access. See CWE-129: Improper Validation of Array Index (\"https://cwe.mitre.org/data/definitions/129.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-unsafe-call-within-signal-handler to disable it. This diagnostic warns for paths through the code in which a function known to be async- signal-unsafe (such as \"fprintf\") is called from a signal handler. See CWE-479: Signal Handler Use of a Non-reentrant Function (\"https://cwe.mitre.org/data/definitions/479.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-use-after-free to disable it. This diagnostic warns for paths through the code in which a pointer is used after a deallocator is called on it: either \"free\", or a deallocator referenced by attribute \"malloc\". See CWE-416: Use After Free (\"https://cwe.mitre.org/data/definitions/416.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-use-of-pointer-in-stale-stack-frame to disable it. This diagnostic warns for paths through the code in which a pointer is dereferenced that points to a variable in a stale stack frame."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-va-arg-type-mismatch to disable it. This diagnostic warns for interprocedural paths through the code for which the analyzer detects an attempt to use \"vaarg\" to extract a value passed to a variadic call, but uses a type that does not match that of the expression passed to the call. See CWE-686: Function Call With Incorrect Argument Type (\"https://cwe.mitre.org/data/definitions/686.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-va-list-exhausted to disable it. This diagnostic warns for interprocedural paths through the code for which the analyzer detects an attempt to use \"vaarg\" to access the next value passed to a variadic call, but all of the values in the \"valist\" have already been consumed. See CWE-685: Function Call With Incorrect Number of Arguments (\"https://cwe.mitre.org/data/definitions/685.html\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-va-list-leak to disable it. This diagnostic warns for interprocedural paths through the code for which the analyzer detects that \"vastart\" or \"vacopy\" has been called on a \"valist\" without a corresponding call to \"vaend\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-va-list-use-after-va-end to disable it. This diagnostic warns for interprocedural paths through the code for which the analyzer detects an attempt to use a \"valist\" after \"vaend\" has been called on it. \"valist\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-write-to-const to disable it. This diagnostic warns for paths through the code in which the analyzer detects an attempt to write through a pointer to a \"const\" object. However, the analyzer does not prioritize detection of such paths, so false negatives are more likely relative to other warnings."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-write-to-string-literal to disable it. This diagnostic warns for paths through the code in which the analyzer detects an attempt to write through a pointer to a string literal. However, the analyzer does not prioritize detection of such paths, so false negatives are more likely relative to other warnings."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This warning requires -fanalyzer, which enables it; use -Wno-analyzer-use-of-uninitialized-value to disable it. This diagnostic warns for paths through the code in which an uninitialized value is used. See CWE-457: Use of Uninitialized Variable (\"https://cwe.mitre.org/data/definitions/457.html\"). The analyzer has hardcoded knowledge about the behavior of the following memory-management functions: *<\"alloca\"> *<The built-in functions \"builtinalloc\",> \"builtinallocwithalign\", @item \"builtincalloc\", \"builtinfree\", \"builtinmalloc\", \"builtinmemcpy\", \"builtinmemcpychk\", \"builtinmemset\", \"builtinmemsetchk\", \"builtinrealloc\", \"builtinstackrestore\", and \"builtinstacksave\" *<\"calloc\"> *<\"free\"> *<\"malloc\"> *<\"memset\"> *<\"operator delete\"> *<\"operator delete []\"> *<\"operator new\"> *<\"operator new []\"> *<\"realloc\"> *<\"strdup\"> *<\"strndup\"> of the following functions for working with file descriptors: *<\"open\"> *<\"close\"> *<\"creat\"> *<\"dup\", \"dup2\" and \"dup3\"> *<\"isatty\"> *<\"pipe\", and \"pipe2\"> *<\"read\"> *<\"write\"> *<\"socket\", \"bind\", \"listen\", \"accept\", and \"connect\"> of the following functions for working with \"<stdio.h>\" streams: *<The built-in functions \"builtinfprintf\",> \"builtinfprintfunlocked\", \"builtinfputc\", \"builtinfputcunlocked\", \"builtinfputs\", \"builtinfputsunlocked\", \"builtinfwrite\", \"builtinfwriteunlocked\", \"builtinprintf\", \"builtinprintfunlocked\", \"builtinputc\", \"builtinputchar\", \"builtinputcharunlocked\", \"builtinputcunlocked\", \"builtinputs\", \"builtinputsunlocked\", \"builtinvfprintf\", and \"builtinvprintf\" *<\"fopen\"> *<\"fclose\"> *<\"ferror\"> *<\"fgets\"> *<\"fgetsunlocked\"> *<\"fileno\"> *<\"fread\"> *<\"getc\"> *<\"getchar\"> *<\"fprintf\"> *<\"printf\"> *<\"fwrite\"> and of the following functions: *<The built-in functions \"builtinexpect\",> \"builtinexpectwithprobability\", \"builtinstrchr\", \"builtinstrcpy\", \"builtinstrcpychk\", \"builtinstrlen\", \"builtinvacopy\", and \"builtinvastart\" *<The GNU extensions \"error\" and \"erroratline\"> *<\"getpass\"> *<\"longjmp\"> *<\"putenv\"> *<\"setjmp\"> *<\"siglongjmp\"> *<\"signal\"> *<\"sigsetjmp\"> *<\"strchr\"> *<\"strlen\"> In addition, various functions with an \"analyzer\" prefix have special meaning to the analyzer, described in the GCC Internals manual. Pertinent parameters for controlling the exploration are: *<--param analyzer-bb-explosion-factor=value> *<--param analyzer-max-enodes-per-program-point=value> *<--param analyzer-max-recursion-depth=value> *<--param analyzer-min-snodes-for-call-summary=value> The following options control the analyzer."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Simplify interprocedural analysis by computing the effect of certain calls, rather than exploring all paths through the function from callsite to each possible return. If enabled, call summaries are only used for functions with more than one call site, and that are sufficiently complicated (as per --param analyzer-min-snodes-for-call-summary=value)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Restrict the analyzer to run just the named checker, and enable it. Some checkers are disabled by default (even with -fanalyzer), such as the \"taint\" checker that implements -Wanalyzer-tainted-array-index, and this option is required to enable them. Note: currently, -fanalyzer-checker=taint disables the following warnings from -fanalyzer: -Wanalyzer-deref-before-check -Wanalyzer-double-fclose -Wanalyzer-double-free -Wanalyzer-exposure-through-output-file -Wanalyzer-fd-access-mode-mismatch -Wanalyzer-fd-double-close -Wanalyzer-fd-leak -Wanalyzer-fd-use-after-close -Wanalyzer-fd-use-without-check -Wanalyzer-file-leak -Wanalyzer-free-of-non-heap -Wanalyzer-malloc-leak -Wanalyzer-mismatching-deallocation -Wanalyzer-null-argument -Wanalyzer-null-dereference -Wanalyzer-possible-null-argument -Wanalyzer-possible-null-dereference -Wanalyzer-unsafe-call-within-signal-handler -Wanalyzer-use-after-free -Wanalyzer-va-list-leak -Wanalyzer-va-list-use-after-va-end"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is intended for analyzer developers. By default the analyzer verifies that there is a feasible control flow path for each diagnostic it emits: that the conditions that hold are not mutually exclusive. Diagnostics for which no feasible path can be found are rejected. This filtering can be suppressed with -fno-analyzer-feasibility, for debugging issues in this code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is intended for analyzer developers. Internally the analyzer builds an \"exploded graph\" that combines control flow graphs with data flow information. By default, an edge in this graph can contain the effects of a run of multiple statements within a basic block. With -fanalyzer-fine-grained, each statement gets its own edge."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is intended for analyzer developers: if multiple diagnostics have been detected as being duplicates of each other, it emits a note when reporting the best diagnostic, giving the number of additional diagnostics that were suppressed by the deduplication logic."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is intended for analyzer developers. By default the analyzer attempts to simplify analysis by merging sufficiently similar states at each program point as it builds its \"exploded graph\". With -fno-analyzer-state-merge this merging can be suppressed, for debugging state-handling issues."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is intended for analyzer developers. By default the analyzer attempts to simplify analysis by purging aspects of state at a program point that appear to no longer be relevant e.g. the values of locals that aren't accessed later in the function and which aren't relevant to leak analysis. With -fno-analyzer-state-purge this purging of state can be suppressed, for debugging state-handling issues."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is intended for analyzer developers. By default the analyzer will stop exploring an execution path after encountering certain diagnostics, in order to avoid potentially issuing a cascade of follow-up diagnostics. The diagnostics that terminate analysis along a path are: *<-Wanalyzer-null-argument> *<-Wanalyzer-null-dereference> *<-Wanalyzer-use-after-free> *<-Wanalyzer-use-of-pointer-in-stale-stack-frame> *<-Wanalyzer-use-of-uninitialized-value> With -fno-analyzer-suppress-followups the analyzer will continue to explore such paths even after such diagnostics, which may be helpful for debugging issues in the analyzer, or for microbenchmarks for detecting undefined behavior."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option enables transitivity of constraints within the analyzer."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is intended for analyzer developers. -fanalyzer runs relatively late compared to other code analysis tools, and some optimizations have already been applied to the code. In particular function inlining may have occurred, leading to the interprocedural execution paths emitted by the analyzer containing function frames that don't correspond to those in the original source code. By default the analyzer attempts to reconstruct the original function frames, and to emit events showing the inlined calls. With -fno-analyzer-undo-inlining this attempt to reconstruct the original frame information can be be disabled, which may be of help when debugging issues in the analyzer."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is intended for analyzer developers. It enables more verbose, lower-level detail in the descriptions of control flow within diagnostic paths."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is intended for analyzer developers. It enables more verbose, lower-level detail in the descriptions of events relating to state machines within diagnostic paths."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls the complexity of the control flow paths that are emitted for analyzer diagnostics. The level can be one of: 0 At this level, interprocedural call and return events are displayed, along with the most pertinent state-change events relating to a diagnostic. For example, for a double-\"free\" diagnostic, both calls to \"free\" will be shown. 1 As per the previous level, but also show events for the entry to each function. 2 As per the previous level, but also show events relating to control flow that are significant to triggering the issue (e.g. \"true path taken\" at a conditional). This level is the default. 3 As per the previous level, but show all control flow events, not just significant ones. 4 This level is intended for analyzer developers; it adds various other events intended for debugging the analyzer."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dump internal details about what the analyzer is doing to file.analyzer.txt. -fdump-analyzer-stderr overrides this option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dump internal details about what the analyzer is doing to stderr. This option overrides -fdump-analyzer."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dump a representation of the call graph suitable for viewing with GraphViz to file.callgraph.dot."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dump a representation of the \"exploded graph\" suitable for viewing with GraphViz to file.eg.dot. Nodes are color-coded based on state-machine states to emphasize state changes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit diagnostics showing where nodes in the \"exploded graph\" are in relation to the program source."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dump a textual representation of the \"exploded graph\" to file.eg.txt."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dump a textual representation of the \"exploded graph\" to one dump file per node, to file.eg-id.txt. This is typically a large number of dump files."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dump a textual representation of the \"exploded path\" for each diagnostic to file.idx.kind.epath.txt."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dump internal details about the analyzer's search for feasible paths. The details are written in a form suitable for viewing with GraphViz to filenames of the form file.*.fg.dot, file.*.tg.dot, and file.*.fpath.txt."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dump a compressed JSON representation of analyzer internals to file.analyzer.json.gz. The precise format is subject to change."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "As per -fdump-analyzer-supergraph, dump a representation of the \"supergraph\" suitable for viewing with GraphViz, but annotate the graph with information on what state will be purged at each node. The graph is written to file.state-purge.dot."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dump representations of the \"supergraph\" suitable for viewing with GraphViz to file.supergraph.dot and to file.supergraph-eg.dot. These show all of the control flow graphs in the program, with interprocedural edges for calls and returns. The second dump contains annotations showing nodes in the \"exploded graph\" and diagnostics associated with them."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit custom warnings with internal details intended for analyzer developers."
        },
        {
            "flag": "-g",
            "long": null,
            "arg": null,
            "description": "XCOFF, or DWARF). GDB can work with this debugging information. On most systems that use stabs format, -g enables use of extra debugging information that only GDB can use; this extra information makes debugging work better in GDB but probably makes other debuggers crash or refuse to read the program. If you want to control for certain whether to generate the extra information, use -gvms (see below)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Produce debugging information for use by GDB. This means to use the most expressive format available (DWARF, stabs, or the native format if neither of those are supported), including GDB extensions if at all possible."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Produce debugging information in DWARF format (if that is supported). The value of version may be either 2, 3, 4 or 5; the default version for most targets is 5 (with the exception of VxWorks, TPF and Darwin/Mac OS X, which default to version 2, and AIX, which defaults to version 4). Note that with DWARF Version 2, some ports require and always use some non-conflicting DWARF 3 extensions in the unwind tables. Version 4 may require GDB 7.0 and -fvar-tracking-assignments for maximum benefit. Version 5 requires GDB 8.0 or higher. GCC no longer supports DWARF Version 1, which is substantially different than Version 2 and later. For historical reasons, some other DWARF-related options such as -fno-dwarf2-cfi-asm) retain a reference to DWARF Version 2 in their names, but apply to all currently-supported versions of DWARF."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Request BTF debug information. BTF is the default debugging format for the eBPF target. On other targets, like x86, BTF debug information can be generated along with DWARF debug information when both of the debug formats are enabled explicitly via their respective command line options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Request CTF debug information and use level to specify how much CTF debug information should be produced. If -gctf is specified without a value for level, the default level of CTF debug information is 2. CTF debug information can be generated along with DWARF debug information when both of the debug formats are enabled explicitly via their respective command line options. Level 0 produces no CTF debug information at all. Thus, -gctf0 negates -gctf. Level 1 produces CTF information for tracebacks only. This includes callsite information, but does not include type information. Level 2 produces type information for entities (functions, data objects etc.) at file- scope or global-scope only."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Produce debugging information in Alpha/VMS debug format (if that is supported). This is the format used by DEBUG on Alpha/VMS systems."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Request debugging information and also use level to specify how much information. The default level is 2. Level 0 produces no debug information at all. Thus, -g0 negates -g. Level 1 produces minimal information, enough for making backtraces in parts of the program that you don't plan to debug. This includes descriptions of functions and external variables, and line number tables, but no information about local variables. Level 3 includes extra information, such as all the macro definitions present in the program. Some debuggers support macro expansion when you use -g3. If you use multiple -g options, with or without level numbers, the last such option is the one that is effective. -gdwarf does not accept a concatenated debug level, to avoid confusion with -gdwarf-level. Instead use an additional -glevel option to change the debug level for DWARF."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "By default, no debug information is produced for symbols that are not actually used. Use this option if you want debug information for all symbols."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Instead of emitting debugging information for a C++ class in only one object file, emit it in all object files using the class. This option should be used only with debuggers that are unable to handle the way GCC normally emits debugging information for classes because using this option increases the size of debugging information by as much as a factor of two."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Direct the linker to not merge together strings in the debugging information that are identical in different object files. Merging is not supported by all assemblers or linkers. Merging decreases the size of the debug information in the output file at the cost of increasing link processing time. Merging is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When compiling files residing in directory old, record debugging information describing them as if the files resided in directory new instead. This can be used to replace a build-time path with an install-time path in the debug info. It can also be used to change an absolute path to a relative path by using . for new. This can give more reproducible builds, which are location independent, but may require an extra command to tell GDB where to find the source files. See also -ffile-prefix-map and -fcanon-prefix-map."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Run variable tracking pass. It computes where variables are stored at each position in code. Better debugging information is then generated (if the debugging information format supports this information). It is enabled by default when compiling with optimization (-Os, -O, -O2, ...), debugging information (-g) and the debug info format supports it."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Annotate assignments to user variables early in the compilation and attempt to carry the annotations over throughout the compilation all the way to the end, in an attempt to improve debug information while optimizing. Use of -gdwarf-4 is recommended along with it. It can be enabled even if var-tracking is disabled, in which case annotations are created and maintained, but discarded at the end. By default, this flag is enabled together with -fvar-tracking, except when selective scheduling is enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If DWARF debugging information is enabled, separate as much debugging information as possible into a separate output file with the extension .dwo. This option allows the build system to avoid linking files with debug information. To be useful, this option requires a debugger capable of reading .dwo files."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If DWARF debugging information is enabled, the -gdwarf32 selects the 32-bit DWARF format and the -gdwarf64 selects the 64-bit DWARF format. The default is target specific, on most targets it is -gdwarf32 though. The 32-bit DWARF format is smaller, but can't support more than 2GiB of debug information in any of the DWARF debug information sections. The 64-bit DWARF format allows larger debug information and might not be well supported by all consumers yet."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Add description attributes to some DWARF DIEs that have no name attribute, such as artificial variables, external references and call site parameter DIEs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate DWARF \".debugpubnames\" and \".debugpubtypes\" sections."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate \".debugpubnames\" and \".debugpubtypes\" sections in a format suitable for conversion into a GDB index. This option is only useful with a linker that can produce GDB index version 7."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When using DWARF Version 4 or higher, type DIEs can be put into their own \".debugtypes\" section instead of making them part of the \".debuginfo\" section. It is more efficient to put them in a separate comdat section since the linker can then remove duplicates. But not all DWARF consumers support \".debugtypes\" sections yet and on some objects \".debugtypes\" produces larger instead of smaller debugging information."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This switch causes the command-line options used to invoke the compiler that may affect code generation to be appended to the DWATproducer attribute in DWARF debugging information. The options are concatenated with spaces separating them from each other and from the compiler version. It is enabled by default. See also -frecord-gcc-switches for another way of storing compiler options into the object file."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disallow using extensions of later DWARF standard version than selected with -gdwarf-version. On most targets using non-conflicting DWARF extensions from later standard versions is allowed."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow using extensions of later DWARF standard version than selected with -gdwarf-version."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Inform the compiler that the assembler supports \".loc\" directives. It may then use them for the assembler to generate DWARF2+ line number tables. This is generally desirable, because assembler-generated line-number tables are a lot more compact than those the compiler can generate itself. This option will be enabled by default if, at GCC configure time, the assembler was found to support such directives."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force GCC to generate DWARF2+ line number tables internally, if DWARF2+ line number tables are to be generated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Inform the compiler that the assembler supports \"view\" assignment and reset assertion checking in \".loc\" directives. This option will be enabled by default if, at GCC configure time, the assembler was found to support them."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force GCC to assign view numbers internally, if -gvariable-location-views are explicitly requested."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit location column information into DWARF debugging information, rather than just file and line. This option is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option causes GCC to create markers in the internal representation at the beginning of statements, and to keep them roughly in place throughout compilation, using them to guide the output of \"isstmt\" markers in the line number table. This is enabled by default when compiling with optimization (-Os, -O1, -O2, ...), and outputting DWARF 2 debug information at the normal level."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Augment variable location lists with progressive view numbers implied from the line number table. This enables debug information consumers to inspect state at certain points of the program, even if no instructions associated with the corresponding source locations are present at that point. If the assembler lacks support for view numbers in line number tables, this will cause the compiler to emit the line number table, which generally makes them somewhat less compact. The augmented line number tables and location lists are fully backward-compatible, so they can be consumed by debug information consumers that are not aware of these augmentations, but they won't derive any benefit from them either. This is enabled by default when outputting DWARF 2 debug information at the normal level, as long as there is assembler support, -fvar-tracking-assignments is enabled and -gstrict-dwarf is not. When assembler support is not available, this may still be enabled, but it will force GCC to output internal line number tables, and if -ginternal-reset-location-views is not enabled, that will most certainly lead to silently mismatching location views. There is a proposed representation for view numbers that is not backward compatible with the location list format introduced in DWARF 5, that can be enabled with -gvariable-location-views=incompat5. This option may be removed in the future, is only provided as a reference implementation of the proposed representation. Debug information consumers are not expected to support this extended format, and they would be rendered unable to decode location lists using it."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Attempt to determine location views that can be omitted from location view lists. This requires the compiler to have very accurate insn length estimates, which isn't always the case, and it may cause incorrect view lists to be generated silently when using an assembler that does not support location view lists. The GNU assembler will flag any such error as a \"view number mismatch\". This is only enabled on ports that define a reliable estimation function."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate extended debug information for inlined functions. Location view tracking markers are inserted at inlined entry points, so that address and view numbers can be computed and output in debug information. This can be enabled independently of location views, in which case the view numbers won't be output, but it can only be enabled along with statement frontiers, and it is only enabled by default if location views are enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Produce compressed debug sections in DWARF format, if that is supported. If type is not given, the default type depends on the capabilities of the assembler and linker used. type may be one of none (don't compress debug sections), or zlib (use zlib compression in ELF gABI format). If the linker doesn't support writing compressed debug sections, the option is rejected. Otherwise, if the assembler does not support them, -gz is silently ignored when producing object files."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit debug information for struct-like types only when the base name of the compilation source file matches the base name of file in which the struct is defined. This option substantially reduces the size of debugging information, but at significant potential loss in type information to the debugger. See -femit-struct-debug-reduced for a less aggressive option. See -femit-struct-debug-detailed for more detailed control. This option works only with DWARF debug output."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit debug information for struct-like types only when the base name of the compilation source file matches the base name of file in which the type is defined, unless the struct is a template or defined in a system header. This option significantly reduces the size of debugging information, with some potential loss in type information to the debugger. See -femit-struct-debug-baseonly for a more aggressive option. See -femit-struct-debug-detailed for more detailed control. This option works only with DWARF debug output."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the struct-like types for which the compiler generates debug information. The intent is to reduce duplicate struct debug information between different object files within the same program. This option is a detailed version of -femit-struct-debug-reduced and -femit-struct-debug-baseonly, which serves for most needs. A specification has the syntax[dir:|ind:][ord:|gen:](any|sys|base|none) The optional first word limits the specification to structs that are used directly (dir:) or used indirectly (ind:). A struct type is used directly when it is the type of a variable, member. Indirect uses arise through pointers to structs. That is, when use of an incomplete struct is valid, the use is indirect. An example is struct one direct; struct two * indirect;. The optional second word limits the specification to ordinary structs (ord:) or generic structs (gen:). Generic structs are a bit complicated to explain. For C++, these are non-explicit specializations of template classes, or non-template classes within the above. Other programming languages have generics, but -femit-struct-debug-detailed does not yet implement them. The third word specifies the source files for those structs for which the compiler should emit debug information. The values none and any have the normal meaning. The value base means that the base of name of the file in which the type declaration appears must match the base of the name of the main compilation file. In practice, this means that when compiling foo.c, debug information is generated for types declared in that file and foo.h, but not other header files. The value sys means those types satisfying base or declared in system or compiler headers. You may need to experiment to determine the best settings for your application. The default is -femit-struct-debug-detailed=all. This option works only with DWARF debug output."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit DWARF unwind info as compiler generated \".ehframe\" section instead of using GAS \".cfi*\" directives."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Normally, when producing DWARF output, GCC avoids producing debug symbol output for types that are nowhere used in the source file being compiled. Sometimes it is useful to have GCC emit debugging information for all types declared in a compilation unit, regardless of whether or not they are actually used in that compilation unit, for example if, in the debugger, you want to cast a value to a type that is not actually used in your program (but is declared). More often, however, this results in a significant amount of wasted space."
        },
        {
            "flag": "-O",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "large function. With -O, the compiler tries to reduce code size and execution time, without performing any optimizations that take a great deal of compilation time. -O turns on the following optimization flags: -fauto-inc-dec -fbranch-count-reg -fcombine-stack-adjustments -fcompare-elim -fcprop-registers -fdce -fdefer-pop -fdelayed-branch -fdse -fforward-propagate -fguess-branch-probability -fif-conversion -fif-conversion2 -finline-functions-called-once -fipa-modref -fipa-profile -fipa-pure-const -fipa-reference -fipa-reference-addressable -fmerge-constants -fmove-loop-invariants -fmove-loop-stores -fomit-frame-pointer -freorder-blocks -fshrink-wrap -fshrink-wrap-separate -fsplit-wide-types -fssa-backprop -fssa-phiopt -ftree-bit-ccp -ftree-ccp -ftree-ch -ftree-coalesce-vars -ftree-copy-prop -ftree-dce -ftree-dominator-opts -ftree-dse -ftree-forwprop -ftree-fre -ftree-phiprop -ftree-pta -ftree-scev-cprop -ftree-sink -ftree-slsr -ftree-sra -ftree-ter -funit-at-a-time"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "a space-speed tradeoff. As compared to -O, this option increases both compilation time and the performance of the generated code. -O2 turns on all optimization flags specified by -O1. It also turns on the following optimization flags: -falign-functions -falign-jumps -falign-labels -falign-loops -fcaller-saves -fcode-hoisting -fcrossjumping -fcse-follow-jumps -fcse-skip-blocks -fdelete-null-pointer-checks -fdevirtualize -fdevirtualize-speculatively -fexpensive-optimizations -ffinite-loops -fgcse -fgcse-lm -fhoist-adjacent-loads -finline-functions -finline-small-functions -findirect-inlining -fipa-bit-cp -fipa-cp -fipa-icf -fipa-ra -fipa-sra -fipa-vrp -fisolate-erroneous-paths-dereference -flra-remat -foptimize-sibling-calls -foptimize-strlen -fpartial-inlining -fpeephole2 -freorder-blocks-algorithm=stc -freorder-blocks-and-partition -freorder-functions -frerun-cse-after-loop -fschedule-insns -fschedule-insns2 -fsched-interblock -fsched-spec -fstore-merging -fstrict-aliasing -fthread-jumps -ftree-builtin-call-dce -ftree-loop-vectorize -ftree-pre -ftree-slp-vectorize -ftree-switch-conversion -ftree-tail-merge -ftree-vrp -fvect-cost-model=very-cheap Please note the warning under -fgcse about invoking -O2 on programs that use computed gotos. NOTE: In Ubuntu 8.10 and later versions, -DFORTIFYSOURCE=2, in Ubuntu 24.04 and later versions, -DFORTIFYSOURCE=3, is set by default, and is activated when -O is set to 2 or higher. This enables additional compile-time and run-time checks for several libc functions. To disable, specify either -UFORTIFYSOURCE or -DFORTIFYSOURCE=0. NOTE: In Debian 13 and Ubuntu 24.04 and later versions, -DTIMEBITS=64 together with -DFILEOFFSETBITS=64 is set by default on the 32bit architectures armel, armhf, hppa, m68k, mips, mipsel, powerpc and sh4."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "following optimization flags: -fgcse-after-reload -fipa-cp-clone -floop-interchange -floop-unroll-and-jam -fpeel-loops -fpredictive-commoning -fsplit-loops -fsplit-paths -ftree-loop-distribution -ftree-partial-pre -funswitch-loops -fvect-cost-model=dynamic -fversion-loops-for-strides"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "code size: -falign-functions -falign-jumps -falign-labels -falign-loops -fprefetch-loop-arrays -freorder-blocks-algorithm=stc It also enables -finline-functions, causes the compiler to tune for code size rather than execution speed, and performs further optimizations designed to reduce code size."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disregard strict standards compliance. -Ofast enables all -O3 optimizations. It also enables optimizations that are not valid for all standard-compliant programs. It turns on -ffast-math, -fallow-store-data-races and the Fortran-specific -fstack-arrays, unless -fmax-stack-var-size is specified, and -fno-protect-parens. It turns off -fsemantic-interposition."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "standard edit-compile-debug cycle, offering a reasonable level of optimization while maintaining fast compilation and a good debugging experience. It is a better choice than -O0 for producing debuggable code because some compiler passes that collect debug information are disabled at -O0. Like -O0, -Og completely disables a number of optimization passes so that individual options controlling them have no effect. Otherwise -Og enables all -O1 optimization flags except for those that may interfere with debugging: -fbranch-count-reg -fdelayed-branch -fdse -fif-conversion -fif-conversion2 -finline-functions-called-once -fmove-loop-invariants -fmove-loop-stores -fssa-phiopt -ftree-bit-ccp -ftree-dse -ftree-pta -ftree-sra"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "instructions executed if those instructions require fewer bytes to encode. -Oz behaves similarly to -Os including enabling most -O2 optimizations. If you use multiple -O options, with or without level numbers, the last such option is the one that is effective. Options of the form -fflag specify machine-independent flags. Most flags have both positive and negative forms; the negative form of -ffoo is -fno-foo. In the table below, only one of the forms is listed---the one you typically use. You can figure out the other form by either removing no- or adding it. The following options control specific optimizations. They are either activated by -O options or are related to ones that are. You can use the following flags in the rare cases when \"fine-tuning\" of optimizations to be performed is desired."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "For machines that must pop arguments after a function call, always pop the arguments as soon as each function returns. At levels -O1 and higher, -fdefer-pop is the default; this allows the compiler to let arguments accumulate on the stack for several function calls and pop them all at once."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform a forward propagation pass on RTL. The pass tries to combine two instructions and checks if the result can be simplified. If loop unrolling is active, two passes are performed and the second is scheduled after loop unrolling. This option is enabled by default at optimization levels -O1, -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "-ffp-contract=off disables floating-point expression contraction. -ffp-contract=fast enables floating-point expression contraction such as forming of fused multiply-add operations if the target has native support for them. -ffp-contract=on enables floating- point expression contraction if allowed by the language standard. This is currently not implemented and treated equal to -ffp-contract=off. The default is -ffp-contract=fast."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Omit the frame pointer in functions that don't need one. This avoids the instructions to save, set up and restore the frame pointer; on many targets it also makes an extra register available. On some targets this flag has no effect because the standard calling sequence always uses a frame pointer, so it cannot be omitted. Note that -fno-omit-frame-pointer doesn't guarantee the frame pointer is used in all functions. Several targets always omit the frame pointer in leaf functions. Enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Optimize sibling and tail recursive calls. Enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Optimize various standard C string functions (e.g. \"strlen\", \"strchr\" or \"strcpy\") and their \"FORTIFYSOURCE\" counterparts into faster alternatives. Enabled at levels -O2, -O3."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not expand any functions inline apart from those marked with the \"alwaysinline\" attribute. This is the default when not optimizing. Single functions can be exempted from inlining by marking them with the \"noinline\" attribute."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Integrate functions into their callers when their body is smaller than expected function call code (so overall size of program gets smaller). The compiler heuristically decides which functions are simple enough to be worth integrating in this way. This inlining applies to all functions, even those not declared inline. Enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Inline also indirect calls that are discovered to be known at compile time thanks to previous inlining. This option has any effect only when inlining itself is turned on by the -finline-functions or -finline-small-functions options. Enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Consider all functions for inlining, even if they are not declared inline. The compiler heuristically decides which functions are worth integrating in this way. If all calls to a given function are integrated, and the function is declared \"static\", then the function is normally not output as assembler code in its own right. Enabled at levels -O2, -O3, -Os. Also enabled by -fprofile-use and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Consider all \"static\" functions called once for inlining into their caller even if they are not marked \"inline\". If a call to a given function is integrated, then the function is not output as assembler code in its own right. Enabled at levels -O1, -O2, -O3 and -Os, but not -Og."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Inline functions marked by \"alwaysinline\" and functions whose body seems smaller than the function call overhead early before doing -fprofile-generate instrumentation and real inlining pass. Doing so makes profiling significantly cheaper and usually inlining faster on programs having large chains of nested wrapper functions. Enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform interprocedural scalar replacement of aggregates, removal of unused parameters and replacement of parameters passed by reference by parameters passed by value. Enabled at levels -O2, -O3 and -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "By default, GCC limits the size of functions that can be inlined. This flag allows coarse control of this limit. n is the size of functions that can be inlined in number of pseudo instructions. Inlining is actually controlled by a number of parameters, which may be specified individually by using --param name=value. The -finline-limit=n option sets some of these parameters as follows: max-inline-insns-single is set to n/2. max-inline-insns-auto is set to n/2. See below for a documentation of the individual parameters controlling inlining and for the defaults of these parameters. Note: there may be no value to -finline-limit that results in default behavior. Note: pseudo instruction represents, in this particular context, an abstract measurement of function's size. In no way does it represent a count of assembly instructions and as such its exact meaning might change from one release to an another."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This is a more fine-grained version of -fkeep-inline-functions, which applies only to functions that are declared using the \"dllexport\" attribute or declspec."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "In C, emit \"static\" functions that are declared \"inline\" into the object file, even if the function has been inlined into all of its callers. This switch does not affect functions using the \"extern inline\" extension in GNU C90. In C++, emit any and all inline functions into the object file."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit \"static\" functions into the object file, even if the function is never used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit variables declared \"static const\" when optimization isn't turned on, even if the variables aren't referenced. GCC enables this option by default. If you want to force the compiler to check if a variable is referenced, regardless of whether or not optimization is turned on, use the -fno-keep-static-consts option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Attempt to merge identical constants (string constants and floating-point constants) across compilation units. This option is the default for optimized compilation if the assembler and linker support it. Use -fno-merge-constants to inhibit this behavior. Enabled at levels -O1, -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Attempt to merge identical constants and identical variables. This option implies -fmerge-constants. In addition to -fmerge-constants this considers e.g. even constant initialized arrays or initialized constant variables with integral or floating-point types. Languages like C or C++ require each variable, including multiple instances of the same variable in recursive calls, to have distinct locations, so using this option results in non-conforming behavior."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform swing modulo scheduling immediately before the first scheduling pass. This pass looks at innermost loops and reorders their instructions by overlapping different iterations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform more aggressive SMS-based modulo scheduling with register moves allowed. By setting this flag certain anti-dependences edges are deleted, which triggers the generation of reg-moves based on the life-range analysis. This option is effective only with -fmodulo-sched enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable the optimization pass that scans for opportunities to use \"decrement and branch\" instructions on a count register instead of instruction sequences that decrement a register, compare it against zero, and then branch based upon the result. This option is only meaningful on architectures that support such instructions, which include x86, PowerPC, IA-64 and S/390. Note that the -fno-branch-count-reg option doesn't remove the decrement and branch instructions from the generated instruction stream introduced by other optimization passes. The default is -fbranch-count-reg at -O1 and higher, except for -Og."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not put function addresses in registers; make each instruction that calls a constant function contain the function's address explicitly. This option results in less efficient code, but some strange hacks that alter the assembler output may be confused by the optimizations performed when this option is not used. The default is -ffunction-cse"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If the target supports a BSS section, GCC by default puts variables that are initialized to zero into BSS. This can save space in the resulting code. This option turns off this behavior because some programs explicitly rely on variables going to the data section---e.g., so that the resulting executable can find the beginning of that section and/or make assumptions based on that. The default is -fzero-initialized-in-bss."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform optimizations that check to see if a jump branches to a location where another comparison subsumed by the first is found. If so, the first branch is redirected to either the destination of the second branch or a point immediately following it, depending on whether the condition is known to be true or false. Enabled at levels -O1, -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When using a type that occupies multiple registers, such as \"long long\" on a 32-bit system, split the registers apart and allocate them independently. This normally generates better code for those types, but may make debugging more difficult. Enabled at levels -O1, -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Fully split wide types early, instead of very late. This option has no effect unless -fsplit-wide-types is turned on. This is the default on some targets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "In common subexpression elimination (CSE), scan through jump instructions when the target of the jump is not reached by any other path. For example, when CSE encounters an \"if\" statement with an \"else\" clause, CSE follows the jump when the condition tested is false. Enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This is similar to -fcse-follow-jumps, but causes CSE to follow jumps that conditionally skip over blocks. When CSE encounters a simple \"if\" statement with no else clause, -fcse-skip-blocks causes CSE to follow the jump around the body of the \"if\". Enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Re-run common subexpression elimination after loop optimizations are performed. Enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform a global common subexpression elimination pass. This pass also performs global constant and copy propagation. Note: When compiling a program using computed gotos, a GCC extension, you may get better run-time performance if you disable the global common subexpression elimination pass by adding -fno-gcse to the command line. Enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When -fgcse-lm is enabled, global common subexpression elimination attempts to move loads that are only killed by stores into themselves. This allows a loop containing a load/store sequence to be changed to a load outside the loop, and a copy/store within the loop. Enabled by default when -fgcse is enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When -fgcse-sm is enabled, a store motion pass is run after global common subexpression elimination. This pass attempts to move stores out of loops. When used in conjunction with -fgcse-lm, loops containing a load/store sequence can be changed to a load before the loop and a store after the loop. Not enabled at any optimization level."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When -fgcse-las is enabled, the global common subexpression elimination pass eliminates redundant loads that come after stores to the same memory location (both partial and full redundancies). Not enabled at any optimization level."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When -fgcse-after-reload is enabled, a redundant load elimination pass is performed after reload. The purpose of this pass is to clean up redundant spilling. Enabled by -O3, -fprofile-use and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option tells the loop optimizer to use language constraints to derive bounds for the number of iterations of a loop. This assumes that loop code does not invoke undefined behavior by for example causing signed integer overflows or out-of-bound array accesses. The bounds for the number of iterations of a loop are used to guide loop unrolling and peeling and loop exit test optimizations. This option is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option tells the compiler that variables declared in common blocks (e.g. Fortran) may later be overridden with longer trailing arrays. This prevents certain optimizations that depend on knowing the array bounds."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform cross-jumping transformation. This transformation unifies equivalent code and saves code size. The resulting code may or may not perform better than without cross- jumping. Enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Combine increments or decrements of addresses with memory accesses. This pass is always skipped on architectures that do not have instructions to support this. Enabled by default at -O1 and higher on architectures that support this."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform dead code elimination (DCE) on RTL. Enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform dead store elimination (DSE) on RTL. Enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Attempt to transform conditional jumps into branch-less equivalents. This includes use of conditional moves, min, max, set flags and abs instructions, and some tricks doable by standard arithmetics. The use of conditional execution on chips where it is available is controlled by -fif-conversion2. Enabled at levels -O1, -O2, -O3, -Os, but not with -Og."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use conditional execution (where available) to transform conditional jumps into branch- less equivalents. Enabled at levels -O1, -O2, -O3, -Os, but not with -Og."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The C++ ABI requires multiple entry points for constructors and destructors: one for a base subobject, one for a complete object, and one for a virtual destructor that calls operator delete afterwards. For a hierarchy with virtual bases, the base and complete variants are clones, which means two copies of the function. With this option, the base and complete variants are changed to be thunks that call a common implementation. Enabled by -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that programs cannot safely dereference null pointers, and that no code or data element resides at address zero. This option enables simple constant folding optimizations at all optimization levels. In addition, other optimization passes in GCC use this flag to control global dataflow analyses that eliminate useless checks for null pointers; these assume that a memory access to address zero always results in a trap, so that if a pointer is checked after it has already been dereferenced, it cannot be null. Note however that in some environments this assumption is not true. Use -fno-delete-null-pointer-checks to disable this optimization for programs that depend on that behavior. This option is enabled by default on most targets. On Nios II ELF, it defaults to off. On AVR and MSP430, this option is completely disabled. Passes that use the dataflow information are enabled independently at different optimization levels."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Attempt to convert calls to virtual functions to direct calls. This is done both within a procedure and interprocedurally as part of indirect inlining (-findirect-inlining) and interprocedural constant propagation (-fipa-cp). Enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Attempt to convert calls to virtual functions to speculative direct calls. Based on the analysis of the type inheritance graph, determine for a given call the set of likely targets. If the set is small, preferably of size 1, change the call into a conditional deciding between direct and indirect calls. The speculative calls enable more optimizations, such as inlining. When they seem useless after further optimization, they are converted back into original form."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Stream extra information needed for aggressive devirtualization when running the link- time optimizer in local transformation mode. This option enables more devirtualization but significantly increases the size of streamed data. For this reason it is disabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform a number of minor optimizations that are relatively expensive. Enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Attempt to remove redundant extension instructions. This is especially helpful for the x86-64 architecture, which implicitly zero-extends in 64-bit registers after writing to their lower 32-bit half. Enabled for Alpha, AArch64 and x86 at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "In C++ the value of an object is only affected by changes within its lifetime: when the constructor begins, the object has an indeterminate value, and any changes during the lifetime of the object are dead when the object is destroyed. Normally dead store elimination will take advantage of this; if your code relies on the value of the object storage persisting beyond the lifetime of the object, you can use this flag to disable this optimization. To preserve stores before the constructor starts (e.g. because your operator new clears the object storage) but still treat the object as dead after the destructor, you can use -flifetime-dse=1. The default behavior can be explicitly selected with -flifetime-dse=2. -flifetime-dse=0 is equivalent to -fno-lifetime-dse."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Attempt to decrease register pressure through register live range shrinkage. This is helpful for fast processors with small or moderate size register sets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use the specified coloring algorithm for the integrated register allocator. The algorithm argument can be priority, which specifies Chow's priority coloring, or CB, which specifies Chaitin-Briggs coloring. Chaitin-Briggs coloring is not implemented for all architectures, but for those targets that do support it, it is the default because it generates better code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use specified regions for the integrated register allocator. The region argument should be one of the following: all Use all loops as register allocation regions. This can give the best results for machines with a small and/or irregular register set. mixed Use all loops except for loops with small register pressure as the regions. This value usually gives the best results in most cases and for most architectures, and is enabled by default when compiling with optimization for speed (-O, -O2, ...). one Use all functions as a single region. This typically results in the smallest code size, and is enabled by default for -Os or -O0."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use IRA to evaluate register pressure in the code hoisting pass for decisions to hoist expressions. This option usually results in smaller code, but it can slow the compiler down. This option is enabled at level -Os for all targets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use IRA to evaluate register pressure in loops for decisions to move loop invariants. This option usually results in generation of faster and smaller code on machines with large register files (>= 32 registers), but it can slow the compiler down. This option is enabled at level -O3 for some targets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable sharing of stack slots used for saving call-used hard registers living through a call. Each hard register gets a separate stack slot, and as a result function stack frames are larger."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable sharing of stack slots allocated for pseudo-registers. Each pseudo-register that does not get a hard register gets a separate stack slot, and as a result function stack frames are larger."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable CFG-sensitive rematerialization in LRA. Instead of loading values of spilled pseudos, LRA tries to rematerialize (recalculate) values if it is profitable. Enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If supported for the target machine, attempt to reorder instructions to exploit instruction slots available after delayed branch instructions. Enabled at levels -O1, -O2, -O3, -Os, but not at -Og."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If supported for the target machine, attempt to reorder instructions to eliminate execution stalls due to required data being unavailable. This helps machines that have slow floating point or memory load instructions by allowing other instructions to be issued until the result of the load or floating-point instruction is required. Enabled at levels -O2, -O3."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Similar to -fschedule-insns, but requests an additional pass of instruction scheduling after register allocation has been done. This is especially useful on machines with a relatively small number of registers and where memory load instructions take more than one cycle. Enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable instruction scheduling across basic blocks, which is normally enabled when scheduling before register allocation, i.e. with -fschedule-insns or at -O2 or higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable speculative motion of non-load instructions, which is normally enabled when scheduling before register allocation, i.e. with -fschedule-insns or at -O2 or higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable register pressure sensitive insn scheduling before register allocation. This only makes sense when scheduling before register allocation is enabled, i.e. with -fschedule-insns or at -O2 or higher. Usage of this option can improve the generated code and decrease its size by preventing register pressure increase above the number of available hard registers and subsequent spills in register allocation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow speculative motion of some load instructions. This only makes sense when scheduling before register allocation, i.e. with -fschedule-insns or at -O2 or higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow speculative motion of more load instructions. This only makes sense when scheduling before register allocation, i.e. with -fschedule-insns or at -O2 or higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Define how many insns (if any) can be moved prematurely from the queue of stalled insns into the ready list during the second scheduling pass. -fno-sched-stalled-insns means that no insns are moved prematurely, -fsched-stalled-insns=0 means there is no limit on how many queued insns can be moved prematurely. -fsched-stalled-insns without a value is equivalent to -fsched-stalled-insns=1."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Define how many insn groups (cycles) are examined for a dependency on a stalled insn that is a candidate for premature removal from the queue of stalled insns. This has an effect only during the second scheduling pass, and only if -fsched-stalled-insns is used. -fno-sched-stalled-insns-dep is equivalent to -fsched-stalled-insns-dep=0. -fsched-stalled-insns-dep without a value is equivalent to -fsched-stalled-insns-dep=1."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When scheduling after register allocation, use superblock scheduling. This allows motion across basic block boundaries, resulting in faster schedules. This option is experimental, as not all machine descriptions used by GCC model the CPU closely enough to avoid unreliable results from the algorithm. This only makes sense when scheduling after register allocation, i.e. with -fschedule-insns2 or at -O2 or higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the group heuristic in the scheduler. This heuristic favors the instruction that belongs to a schedule group. This is enabled by default when scheduling is enabled, i.e. with -fschedule-insns or -fschedule-insns2 or at -O2 or higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the critical-path heuristic in the scheduler. This heuristic favors instructions on the critical path. This is enabled by default when scheduling is enabled, i.e. with -fschedule-insns or -fschedule-insns2 or at -O2 or higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the speculative instruction heuristic in the scheduler. This heuristic favors speculative instructions with greater dependency weakness. This is enabled by default when scheduling is enabled, i.e. with -fschedule-insns or -fschedule-insns2 or at -O2 or higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the rank heuristic in the scheduler. This heuristic favors the instruction belonging to a basic block with greater size or frequency. This is enabled by default when scheduling is enabled, i.e. with -fschedule-insns or -fschedule-insns2 or at -O2 or higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the last-instruction heuristic in the scheduler. This heuristic favors the instruction that is less dependent on the last instruction scheduled. This is enabled by default when scheduling is enabled, i.e. with -fschedule-insns or -fschedule-insns2 or at -O2 or higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the dependent-count heuristic in the scheduler. This heuristic favors the instruction that has more instructions depending on it. This is enabled by default when scheduling is enabled, i.e. with -fschedule-insns or -fschedule-insns2 or at -O2 or higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Modulo scheduling is performed before traditional scheduling. If a loop is modulo scheduled, later scheduling passes may change its schedule. Use this option to control that behavior."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Schedule instructions using selective scheduling algorithm. Selective scheduling runs instead of the first scheduler pass."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Schedule instructions using selective scheduling algorithm. Selective scheduling runs instead of the second scheduler pass."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable software pipelining of innermost loops during selective scheduling. This option has no effect unless one of -fselective-scheduling or -fselective-scheduling2 is turned on."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When pipelining loops during selective scheduling, also pipeline outer loops. This option has no effect unless -fsel-sched-pipelining is turned on."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Some object formats, like ELF, allow interposing of symbols by the dynamic linker. This means that for symbols exported from the DSO, the compiler cannot perform interprocedural propagation, inlining and other optimizations in anticipation that the function or variable in question may change. While this feature is useful, for example, to rewrite memory allocation functions by a debugging implementation, it is expensive in the terms of code quality. With -fno-semantic-interposition the compiler assumes that if interposition happens for functions the overwriting function will have precisely the same semantics (and side effects). Similarly if interposition happens for variables, the constructor of the variable will be the same. The flag has no effect for functions explicitly declared inline (where it is never allowed for interposition to change semantics) and for symbols explicitly declared weak."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit function prologues only before parts of the function that need it, rather than at the top of the function. This flag is enabled by default at -O and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Shrink-wrap separate parts of the prologue and epilogue separately, so that those parts are only executed when needed. This option is on by default, but has no effect unless -fshrink-wrap is also turned on and the target supports this."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable allocation of values to registers that are clobbered by function calls, by emitting extra instructions to save and restore the registers around such calls. Such allocation is done only when it seems to result in better code. This option is always enabled by default on certain machines, usually those which have no call-preserved registers to use instead. Enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Tracks stack adjustments (pushes and pops) and stack memory references and then tries to find ways to combine them. Enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use caller save registers for allocation if those registers are not used by any called function. In that case it is not necessary to save and restore them around calls. This is only possible if called functions are part of same compilation unit as current function and they are compiled before it. Enabled at levels -O2, -O3, -Os, however the option is disabled if generated code will be instrumented for profiling (-p, or -pg) or if callee's register usage cannot be known exactly (this happens on targets that do not expose prologues and epilogues in RTL)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Attempt to minimize stack usage. The compiler attempts to use less stack space, even if that makes the program slower. This option implies setting the large-stack-frame parameter to 100 and the large-stack-frame-growth parameter to 400."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform reassociation on trees. This flag is enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform code hoisting. Code hoisting tries to move the evaluation of expressions executed on all paths to the function exit as early as possible. This is especially useful as a code size optimization, but it often helps for code speed as well. This flag is enabled by default at -O2 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform partial redundancy elimination (PRE) on trees. This flag is enabled by default at -O2 and -O3."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Make partial redundancy elimination (PRE) more aggressive. This flag is enabled by default at -O3."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform forward propagation on trees. This flag is enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform full redundancy elimination (FRE) on trees. The difference between FRE and PRE is that FRE only considers expressions that are computed on all paths leading to the redundant computation. This analysis is faster than PRE, though it exposes fewer redundancies. This flag is enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform hoisting of loads from conditional pointers on trees. This pass is enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Speculatively hoist loads from both branches of an if-then-else if the loads are from adjacent locations in the same structure and the target architecture has a conditional move instruction. This flag is enabled by default at -O2 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform copy propagation on trees. This pass eliminates unnecessary copy operations. This flag is enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Discover which functions are pure or constant. Enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Discover which static variables do not escape the compilation unit. Enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Discover read-only, write-only and non-addressable static variables. Enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Reduce stack alignment on call sites if possible. Enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform interprocedural pointer analysis and interprocedural modification and reference analysis. This option can cause excessive memory and compile-time usage on large compilation units. It is not enabled by default at any optimization level."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform interprocedural profile propagation. The functions called only from cold functions are marked as cold. Also functions executed once (such as \"cold\", \"noreturn\", static constructors or destructors) are identified. Cold functions and loop less parts of functions executed once are then optimized for size. Enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform interprocedural mod/ref analysis. This optimization analyzes the side effects of functions (memory locations that are modified or referenced) and enables better optimization across the function call boundary. This flag is enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform interprocedural constant propagation. This optimization analyzes the program to determine when values passed to functions are constants and then optimizes accordingly. This optimization can substantially increase performance if the application has constants passed to functions. This flag is enabled by default at -O2, -Os and -O3. It is also enabled by -fprofile-use and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform function cloning to make interprocedural constant propagation stronger. When enabled, interprocedural constant propagation performs function cloning when externally visible function can be called with constant arguments. Because this optimization can create multiple copies of functions, it may significantly increase code size (see --param ipa-cp-unit-growth=value). This flag is enabled by default at -O3. It is also enabled by -fprofile-use and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When enabled, perform interprocedural bitwise constant propagation. This flag is enabled by default at -O2 and by -fprofile-use and -fauto-profile. It requires that -fipa-cp is enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When enabled, perform interprocedural propagation of value ranges. This flag is enabled by default at -O2. It requires that -fipa-cp is enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform Identical Code Folding for functions and read-only variables. The optimization reduces code size and may disturb unwind stacks by replacing a function by equivalent one with a different name. The optimization works more effectively with link-time optimization enabled. Although the behavior is similar to the Gold Linker's ICF optimization, GCC ICF works on different levels and thus the optimizations are not same - there are equivalences that are found only by GCC and equivalences found only by Gold. This flag is enabled by default at -O2 and -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Control GCC's optimizations to produce output suitable for live-patching. If the compiler's optimization uses a function's body or information extracted from its body to optimize/change another function, the latter is called an impacted function of the former. If a function is patched, its impacted functions should be patched too. The impacted functions are determined by the compiler's interprocedural optimizations. For example, a caller is impacted when inlining a function into its caller, cloning a function and changing its caller to call this new clone, or extracting a function's pureness/constness information to optimize its direct or indirect callers, etc. Usually, the more IPA optimizations enabled, the larger the number of impacted functions for each function. In order to control the number of impacted functions and more easily compute the list of impacted function, IPA optimizations can be partially enabled at two different levels. The level argument should be one of the following: inline-clone Only enable inlining and cloning optimizations, which includes inlining, cloning, interprocedural scalar replacement of aggregates and partial inlining. As a result, when patching a function, all its callers and its clones' callers are impacted, therefore need to be patched as well. -flive-patching=inline-clone disables the following optimization flags: -fwhole-program -fipa-pta -fipa-reference -fipa-ra -fipa-icf -fipa-icf-functions -fipa-icf-variables -fipa-bit-cp -fipa-vrp -fipa-pure-const -fipa-reference-addressable -fipa-stack-alignment -fipa-modref inline-only-static Only enable inlining of static functions. As a result, when patching a static function, all its callers are impacted and so need to be patched as well. In addition to all the flags that -flive-patching=inline-clone disables, -flive-patching=inline-only-static disables the following additional optimization flags: -fipa-cp-clone -fipa-sra -fpartial-inlining -fipa-cp When -flive-patching is specified without any value, the default value is inline-clone. This flag is disabled by default. Note that -flive-patching is not supported with link-time optimization (-flto)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Detect paths that trigger erroneous or undefined behavior due to dereferencing a null pointer. Isolate those paths from the main control flow and turn the statement with erroneous or undefined behavior into a trap. This flag is enabled by default at -O2 and higher and depends on -fdelete-null-pointer-checks also being enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Detect paths that trigger erroneous or undefined behavior due to a null value being used in a way forbidden by a \"returnsnonnull\" or \"nonnull\" attribute. Isolate those paths from the main control flow and turn the statement with erroneous or undefined behavior into a trap. This is not currently enabled, but may be enabled by -O2 in the future."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform forward store motion on trees. This flag is enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform sparse conditional bit constant propagation on trees and propagate pointer alignment information. This pass only operates on local scalar variables and is enabled by default at -O1 and higher, except for -Og. It requires that -ftree-ccp is enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform sparse conditional constant propagation (CCP) on trees. This pass only operates on local scalar variables and is enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Propagate information about uses of a value up the definition chain in order to simplify the definitions. For example, this pass strips sign operations if the sign of a value never matters. The flag is enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform pattern matching on SSA PHI nodes to optimize conditional code. This pass is enabled by default at -O1 and higher, except for -Og."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform conversion of simple initializations in a switch to initializations from a scalar array. This flag is enabled by default at -O2 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Look for identical code sequences. When found, replace one with a jump to the other. This optimization is known as tail merging or cross jumping. This flag is enabled by default at -O2 and higher. The compilation time in this pass can be limited using max- tail-merge-comparisons parameter and max-tail-merge-iterations parameter."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform dead code elimination (DCE) on trees. This flag is enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform conditional dead code elimination (DCE) for calls to built-in functions that may set \"errno\" but are otherwise free of side effects. This flag is enabled by default at -O2 and higher if -Os is not also specified."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that a loop with an exit will eventually take the exit and not loop indefinitely. This allows the compiler to remove loops that otherwise have no side-effects, not considering eventual endless looping as such. This option is enabled by default at -O2 for C++ with -std=c++11 or higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform a variety of simple scalar cleanups (constant/copy propagation, redundancy elimination, range propagation and expression simplification) based on a dominator tree traversal. This also performs jump threading (to reduce jumps to jumps). This flag is enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform dead store elimination (DSE) on trees. A dead store is a store into a memory location that is later overwritten by another store without any intervening loads. In this case the earlier store can be deleted. This flag is enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform loop header copying on trees. This is beneficial since it increases effectiveness of code motion optimizations. It also saves one jump. This flag is enabled by default at -O1 and higher. It is not enabled for -Os, since it usually increases code size."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform loop optimizations on trees. This flag is enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform loop nest optimizations. Same as -floop-nest-optimize. To use this code transformation, GCC has to be configured with --with-isl to enable the Graphite loop transformation infrastructure."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the identity transformation for graphite. For every SCoP we generate the polyhedral representation and transform it back to gimple. Using -fgraphite-identity we can check the costs or benefits of the GIMPLE -> GRAPHITE -> GIMPLE transformation. Some minimal optimizations are also performed by the code generator isl, like index splitting and dead code elimination in loops."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the isl based loop nest optimizer. This is a generic loop nest optimizer based on the Pluto optimization algorithms. It calculates a loop structure optimized for data- locality and parallelism. This option is experimental."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use the Graphite data dependence analysis to identify loops that can be parallelized. Parallelize all the loops that can be analyzed to not contain loop carried dependences without checking that it is profitable to parallelize the loops."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "While transforming the program out of the SSA representation, attempt to reduce copying by coalescing versions of different user-defined variables, instead of just compiler temporaries. This may severely limit the ability to debug an optimized program compiled with -fno-var-tracking-assignments. In the negated form, this flag prevents SSA coalescing of user variables. This option is enabled by default if optimization is enabled, and it does very little otherwise."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Attempt to transform conditional jumps in the innermost loops to branch-less equivalents. The intent is to remove control-flow from the innermost loops in order to improve the ability of the vectorization pass to handle these loops. This is enabled by default if vectorization is enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform loop distribution. This flag can improve cache performance on big loop bodies and allow further loop optimizations, like parallelization or vectorization, to take place. For example, the loop DO I = 1, N A(I) = B(I) + C D(I) = E(I) * F ENDDO is transformed to DO I = 1, N A(I) = B(I) + C ENDDO DO I = 1, N D(I) = E(I) * F ENDDO This flag is enabled by default at -O3. It is also enabled by -fprofile-use and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform loop distribution of patterns that can be code generated with calls to a library. This flag is enabled by default at -O2 and higher, and by -fprofile-use and -fauto-profile. This pass distributes the initialization loops and generates a call to memset zero. For example, the loop DO I = 1, N A(I) = 0 B(I) = A(I) + I ENDDO is transformed to DO I = 1, N A(I) = 0 ENDDO DO I = 1, N B(I) = A(I) + I ENDDO and the initialization loop is transformed into a call to memset zero. This flag is enabled by default at -O3. It is also enabled by -fprofile-use and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform loop interchange outside of graphite. This flag can improve cache performance on loop nest and allow further loop optimizations, like vectorization, to take place. For example, the loop for (int i = 0; i < N; i++) for (int j = 0; j < N; j++) for (int k = 0; k < N; k++) c[i][j] = c[i][j] + a[i][k]*b[k][j]; is transformed to for (int i = 0; i < N; i++) for (int k = 0; k < N; k++) for (int j = 0; j < N; j++) c[i][j] = c[i][j] + a[i][k]*b[k][j]; This flag is enabled by default at -O3. It is also enabled by -fprofile-use and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Apply unroll and jam transformations on feasible loops. In a loop nest this unrolls the outer loop by some factor and fuses the resulting multiple inner loops. This flag is enabled by default at -O3. It is also enabled by -fprofile-use and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform loop invariant motion on trees. This pass moves only invariants that are hard to handle at RTL level (function calls, operations that expand to nontrivial sequences of insns). With -funswitch-loops it also moves operands of conditions that are invariant out of the loop, so that we can use just trivial invariantness analysis in loop unswitching. The pass also includes store motion."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Create a canonical counter for number of iterations in loops for which determining number of iterations requires complicated analysis. Later optimizations then may determine the number easily. Useful especially in connection with unrolling."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform final value replacement. If a variable is modified in a loop in such a way that its value when exiting the loop can be determined using only its initial value and the number of loop iterations, replace uses of the final value by such a computation, provided it is sufficiently cheap. This reduces data dependencies and may allow further simplifications. Enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform induction variable optimizations (strength reduction, induction variable merging and induction variable elimination) on trees."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Parallelize loops, i.e., split their iteration space to run in n threads. This is only possible for loops whose iterations are independent and can be arbitrarily reordered. The optimization is only profitable on multiprocessor machines, for loops that are CPU- intensive, rather than constrained e.g. by memory bandwidth. This option implies -pthread, and thus is only supported on targets that have support for -pthread."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform function-local points-to analysis on trees. This flag is enabled by default at -O1 and higher, except for -Og."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform scalar replacement of aggregates. This pass replaces structure references with scalars to prevent committing structures to memory too early. This flag is enabled by default at -O1 and higher, except for -Og."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform merging of narrow stores to consecutive memory addresses. This pass merges contiguous stores of immediate values narrower than a word into fewer wider stores to reduce the number of instructions. This is enabled by default at -O2 and higher as well as -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform temporary expression replacement during the SSA->normal phase. Single use/single def temporaries are replaced at their use location with their defining expression. This results in non-GIMPLE code, but gives the expanders much more complex trees to work on resulting in better RTL generation. This is enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform straight-line strength reduction on trees. This recognizes related expressions involving multiplications and replaces them by less expensive calculations when possible. This is enabled by default at -O1 and higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform vectorization on trees. This flag enables -ftree-loop-vectorize and -ftree-slp-vectorize if not explicitly specified."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform loop vectorization on trees. This flag is enabled by default at -O2 and by -ftree-vectorize, -fprofile-use, and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform basic block vectorization on trees. This flag is enabled by default at -O2 and by -ftree-vectorize, -fprofile-use, and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Initialize automatic variables with either a pattern or with zeroes to increase the security and predictability of a program by preventing uninitialized memory disclosure and use. GCC still considers an automatic variable that doesn't have an explicit initializer as uninitialized, -Wuninitialized and -Wanalyzer-use-of-uninitialized-value will still report warning messages on such automatic variables and the compiler will perform optimization as if the variable were uninitialized. With this option, GCC will also initialize any padding of automatic variables that have structure or union types to zeroes. However, the current implementation cannot initialize automatic variables that are declared between the controlling expression and the first case of a \"switch\" statement. Using -Wtrivial-auto-var-init to report all such cases. The three values of choice are: * uninitialized doesn't initialize any automatic variables. This is C and C++'s default. * pattern Initialize automatic variables with values which will likely transform logic bugs into crashes down the line, are easily recognized in a crash dump and without being values that programmers can rely on for useful program semantics. The current value is byte-repeatable pattern with byte \"0xFE\". The values used for pattern initialization might be changed in the future. * zero Initialize automatic variables with zeroes. The default is uninitialized. You can control this behavior for a specific variable by using the variable attribute \"uninitialized\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Alter the cost model used for vectorization. The model argument should be one of unlimited, dynamic, cheap or very-cheap. With the unlimited model the vectorized code- path is assumed to be profitable while with the dynamic model a runtime check guards the vectorized code-path to enable it only for iteration counts that will likely execute faster than when executing the original scalar loop. The cheap model disables vectorization of loops where doing so would be cost prohibitive for example due to required runtime checks for data dependence or alignment but otherwise is equal to the dynamic model. The very-cheap model only allows vectorization if the vector code would entirely replace the scalar code that is being vectorized. For example, if each iteration of a vectorized loop would only be able to handle exactly four iterations of the scalar loop, the very-cheap model would only allow vectorization if the scalar iteration count is known to be a multiple of four. The default cost model depends on other optimization flags and is either dynamic or cheap."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Alter the cost model used for vectorization of loops marked with the OpenMP simd directive. The model argument should be one of unlimited, dynamic, cheap. All values of model have the same meaning as described in -fvect-cost-model and by default a cost model defined with -fvect-cost-model is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform Value Range Propagation on trees. This is similar to the constant propagation pass, but instead of values, ranges of values are propagated. This allows the optimizers to remove unnecessary range checks like array bound checks and null pointer checks. This is enabled by default at -O2 and higher. Null pointer check elimination is only done if -fdelete-null-pointer-checks is enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Split paths leading to loop backedges. This can improve dead code elimination and common subexpression elimination. This is enabled by default at -O3 and above."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enables expression of values of induction variables in later iterations of the unrolled loop using the value in the first iteration. This breaks long dependency chains, thus improving efficiency of the scheduling passes. A combination of -fweb and CSE is often sufficient to obtain the same effect. However, that is not reliable in cases where the loop body is more complicated than a single basic block. It also does not work at all on some architectures due to restrictions in the CSE pass. This optimization is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With this option, the compiler creates multiple copies of some local variables when unrolling a loop, which can result in superior code. This optimization is enabled by default for PowerPC targets, but disabled by default otherwise."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Inline parts of functions. This option has any effect only when inlining itself is turned on by the -finline-functions or -finline-small-functions options. Enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform predictive commoning optimization, i.e., reusing computations (especially memory loads and stores) performed in previous iterations of loops. This option is enabled at level -O3. It is also enabled by -fprofile-use and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If supported by the target machine, generate instructions to prefetch memory to improve the performance of loops that access large arrays. This option may generate better or worse code; results are highly dependent on the structure of loops within the source code. Disabled at level -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not substitute constants for known return value of formatted output functions such as \"sprintf\", \"snprintf\", \"vsprintf\", and \"vsnprintf\" (but not \"printf\" of \"fprintf\"). This transformation allows GCC to optimize or even eliminate branches based on the known return value of these functions called with arguments that are either constant, or whose values are known to be in a range that makes determining the exact return value possible. For example, when -fprintf-return-value is in effect, both the branch and the body of the \"if\" statement (but not the call to \"snprint\") can be optimized away when \"i\" is a 32-bit or smaller integer because the return value is guaranteed to be at most 8. char buf[9]; if (snprintf (buf, \"%08x\", i) >= sizeof buf) ... The -fprintf-return-value option relies on other optimizations and yields best results with -O2 and above. It works in tandem with the -Wformat-overflow and -Wformat-truncation options. The -fprintf-return-value option is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable any machine-specific peephole optimizations. The difference between -fno-peephole and -fno-peephole2 is in how they are implemented in the compiler; some targets use one, some use the other, a few use both. -fpeephole is enabled by default. -fpeephole2 enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not guess branch probabilities using heuristics. GCC uses heuristics to guess branch probabilities if they are not provided by profiling feedback (-fprofile-arcs). These heuristics are based on the control flow graph. If some branch probabilities are specified by \"builtinexpect\", then the heuristics are used to guess branch probabilities for the rest of the control flow graph, taking the \"builtinexpect\" info into account. The interactions between the heuristics and \"builtinexpect\" can be complex, and in some cases, it may be useful to disable the heuristics so that the effects of \"builtinexpect\" are easier to understand. It is also possible to specify expected probability of the expression with \"builtinexpectwithprobability\" built-in function. The default is -fguess-branch-probability at levels -O, -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Reorder basic blocks in the compiled function in order to reduce number of taken branches and improve code locality. Enabled at levels -O1, -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use the specified algorithm for basic block reordering. The algorithm argument can be simple, which does not increase code size (except sometimes due to secondary effects like alignment), or stc, the \"software trace cache\" algorithm, which tries to put all often executed code together, minimizing the number of branches executed by making extra copies of code. The default is simple at levels -O1, -Os, and stc at levels -O2, -O3."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "In addition to reordering basic blocks in the compiled function, in order to reduce number of taken branches, partitions hot and cold basic blocks into separate sections of the assembly and .o files, to improve paging and cache locality performance. This optimization is automatically turned off in the presence of exception handling or unwind tables (on targets using setjump/longjump or target specific scheme), for linkonce sections, for functions with a user-defined section attribute and on any architecture that does not support named sections. When -fsplit-stack is used this option is not enabled by default (to avoid linker errors), but may be enabled explicitly (if using a working linker). Enabled for x86 at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Reorder functions in the object file in order to improve code locality. This is implemented by using special subsections \".text.hot\" for most frequently executed functions and \".text.unlikely\" for unlikely executed functions. Reordering is done by the linker so object file format must support named sections and linker must place them in a reasonable way. This option isn't effective unless you either provide profile feedback (see -fprofile-arcs for details) or manually annotate functions with \"hot\" or \"cold\" attributes. Enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow the compiler to assume the strictest aliasing rules applicable to the language being compiled. For C (and C++), this activates optimizations based on the type of expressions. In particular, an object of one type is assumed never to reside at the same address as an object of a different type, unless the types are almost the same. For example, an \"unsigned int\" can alias an \"int\", but not a \"void*\" or a \"double\". A character type may alias any other type. Pay special attention to code like this: union aunion { int i; double d; }; int f() { union aunion t; t.d = 3.0; return t.i; } The practice of reading from a different union member than the one most recently written to (called \"type-punning\") is common. Even with -fstrict-aliasing, type-punning is allowed, provided the memory is accessed through the union type. So, the code above works as expected. However, this code might not: int f() { union aunion t; int* ip; t.d = 3.0; ip = &t.i; return *ip; } Similarly, access by taking the address, casting the resulting pointer and dereferencing the result has undefined behavior, even if the cast uses a union type, e.g.: int f() { double d = 3.0; return ((union aunion *) &d)->i; } The -fstrict-aliasing option is enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Controls whether rules of -fstrict-aliasing are applied across function boundaries. Note that if multiple functions gets inlined into a single function the memory accesses are no longer considered to be crossing a function boundary. The -fipa-strict-aliasing option is enabled by default and is effective only in combination with -fstrict-aliasing."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Align the start of functions to the next power-of-two greater than or equal to n, skipping up to m-1 bytes. This ensures that at least the first m bytes of the function can be fetched by the CPU without crossing an n-byte alignment boundary. If m is not specified, it defaults to n. Examples: -falign-functions=32 aligns functions to the next 32-byte boundary, -falign-functions=24 aligns to the next 32-byte boundary only if this can be done by skipping 23 bytes or less, -falign-functions=32:7 aligns to the next 32-byte boundary only if this can be done by skipping 6 bytes or less. The second pair of n2:m2 values allows you to specify a secondary alignment: -falign-functions=64:7:32:3 aligns to the next 64-byte boundary if this can be done by skipping 6 bytes or less, otherwise aligns to the next 32-byte boundary if this can be done by skipping 2 bytes or less. If m2 is not specified, it defaults to n2. Some assemblers only support this flag when n is a power of two; in that case, it is rounded up. -fno-align-functions and -falign-functions=1 are equivalent and mean that functions are not aligned. If n is not specified or is zero, use a machine-dependent default. The maximum allowed n option value is 65536. Enabled at levels -O2, -O3."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If this option is enabled, the compiler tries to avoid unnecessarily overaligning functions. It attempts to instruct the assembler to align by the amount specified by -falign-functions, but not to skip more bytes than the size of the function."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Align all branch targets to a power-of-two boundary. Parameters of this option are analogous to the -falign-functions option. -fno-align-labels and -falign-labels=1 are equivalent and mean that labels are not aligned. If -falign-loops or -falign-jumps are applicable and are greater than this value, then their values are used instead. If n is not specified or is zero, use a machine-dependent default which is very likely to be 1, meaning no alignment. The maximum allowed n option value is 65536. Enabled at levels -O2, -O3."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Align loops to a power-of-two boundary. If the loops are executed many times, this makes up for any execution of the dummy padding instructions. If -falign-labels is greater than this value, then its value is used instead. Parameters of this option are analogous to the -falign-functions option. -fno-align-loops and -falign-loops=1 are equivalent and mean that loops are not aligned. The maximum allowed n option value is 65536. If n is not specified or is zero, use a machine-dependent default. Enabled at levels -O2, -O3."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Align branch targets to a power-of-two boundary, for branch targets where the targets can only be reached by jumping. In this case, no dummy operations need be executed. If -falign-labels is greater than this value, then its value is used instead. Parameters of this option are analogous to the -falign-functions option. -fno-align-jumps and -falign-jumps=1 are equivalent and mean that loops are not aligned. If n is not specified or is zero, use a machine-dependent default. The maximum allowed n option value is 65536. Enabled at levels -O2, -O3."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not remove unused C++ allocations in dead code elimination."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow the compiler to perform optimizations that may introduce new data races on stores, without proving that the variable cannot be concurrently accessed by other threads. Does not affect optimization of local data. It is safe to use this option if it is known that global data will not be accessed by multiple threads. Examples of optimizations enabled by -fallow-store-data-races include hoisting or if- conversions that may cause a value that was already in memory to be re-written with that same value. Such re-writing is safe in a single threaded context but may be unsafe in a multi-threaded context. Note that on some processors, if-conversions may be required in order to enable vectorization. Enabled at level -Ofast."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is left for compatibility reasons. -funit-at-a-time has no effect, while -fno-unit-at-a-time implies -fno-toplevel-reorder and -fno-section-anchors. Enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not reorder top-level functions, variables, and \"asm\" statements. Output them in the same order that they appear in the input file. When this option is used, unreferenced static variables are not removed. This option is intended to support existing code that relies on a particular ordering. For new code, it is better to use attributes when possible. -ftoplevel-reorder is the default at -O1 and higher, and also at -O0 if -fsection-anchors is explicitly requested. Additionally -fno-toplevel-reorder implies -fno-section-anchors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With this option, the compiler turns calls to \"builtinunreachable\" into traps, instead of using them for optimization. This also affects any such calls implicitly generated by the compiler. This option has the same effect as -fsanitize=unreachable -fsanitize-trap=unreachable, but does not affect the values of those options. If -fsanitize=unreachable is enabled, that option takes priority over this one. This option is enabled by default at -O0 and -Og."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Constructs webs as commonly used for register allocation purposes and assign each web individual pseudo register. This allows the register allocation pass to operate on pseudos directly, but also strengthens several other optimization passes, such as CSE, loop optimizer and trivial dead code remover. It can, however, make debugging impossible, since variables no longer stay in a \"home register\". Enabled by default with -funroll-loops."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that the current compilation unit represents the whole program being compiled. All public functions and variables with the exception of \"main\" and those merged by attribute \"externallyvisible\" become static functions and in effect are optimized more aggressively by interprocedural optimizers. With -flto this option has a limited use. In most cases the precise list of symbols used or exported from the binary is known the resolution info passed to the link-time optimizer by the linker plugin. It is still useful if no linker plugin is used or during incremental link step when final code is produced (with -flto -flinker-output=nolto-rel)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option runs the standard link-time optimizer. When invoked with source code, it generates GIMPLE (one of GCC's internal representations) and writes it to special ELF sections in the object file. When the object files are linked together, all the function bodies are read from these ELF sections and instantiated as if they had been part of the same translation unit. To use the link-time optimizer, -flto and optimization options should be specified at compile time and during the final link. It is recommended that you compile all the files participating in the same link with the same options and also specify those options at link time. For example: gcc -c -O2 -flto foo.c gcc -c -O2 -flto bar.c gcc -o myprog -flto -O2 foo.o bar.o The first two invocations to GCC save a bytecode representation of GIMPLE into special ELF sections inside foo.o and bar.o. The final invocation reads the GIMPLE bytecode from foo.o and bar.o, merges the two files into a single internal image, and compiles the result as usual. Since both foo.o and bar.o are merged into a single image, this causes all the interprocedural analyses and optimizations in GCC to work across the two files as if they were a single one. This means, for example, that the inliner is able to inline functions in bar.o into functions in foo.o and vice-versa. Another (simpler) way to enable link-time optimization is: gcc -o myprog -flto -O2 foo.c bar.c The above generates bytecode for foo.c and bar.c, merges them together into a single GIMPLE representation and optimizes them as usual to produce myprog. The important thing to keep in mind is that to enable link-time optimizations you need to use the GCC driver to perform the link step. GCC automatically performs link-time optimization if any of the objects involved were compiled with the -flto command-line option. You can always override the automatic decision to do link-time optimization by passing -fno-lto to the link command. To make whole program optimization effective, it is necessary to make certain whole program assumptions. The compiler needs to know what functions and variables can be accessed by libraries and runtime outside of the link-time optimized unit. When supported by the linker, the linker plugin (see -fuse-linker-plugin) passes information to the compiler about used and externally visible symbols. When the linker plugin is not available, -fwhole-program should be used to allow the compiler to make these assumptions, which leads to more aggressive optimization decisions. When a file is compiled with -flto without -fuse-linker-plugin, the generated object file is larger than a regular object file because it contains GIMPLE bytecodes and the usual final code (see -ffat-lto-objects). This means that object files with LTO information can be linked as normal object files; if -fno-lto is passed to the linker, no interprocedural optimizations are applied. Note that when -fno-fat-lto-objects is enabled the compile stage is faster but you cannot perform a regular, non-LTO link on them. When producing the final binary, GCC only applies link-time optimizations to those files that contain bytecode. Therefore, you can mix and match object files and libraries with GIMPLE bytecodes and final object code. GCC automatically selects which files to optimize in LTO mode and which files to link without further processing. Generally, options specified at link time override those specified at compile time, although in some cases GCC attempts to infer link-time options from the settings used to compile the input files. If you do not specify an optimization level option -O at link time, then GCC uses the highest optimization level used when compiling the object files. Note that it is generally ineffective to specify an optimization level option only at link time and not at compile time, for two reasons. First, compiling without optimization suppresses compiler passes that gather information needed for effective optimization at link time. Second, some early optimization passes can be performed only at compile time and not at link time. There are some code generation flags preserved by GCC when generating bytecodes, as they need to be used during the final link. Currently, the following options and their settings are taken from the first object file that explicitly specifies them: -fcommon, -fexceptions, -fnon-call-exceptions, -fgnu-tm and all the -m target flags. The following options -fPIC, -fpic, -fpie and -fPIE are combined based on the following scheme: B<-fPIC> + B<-fpic> = B<-fpic> B<-fPIC> + B<-fno-pic> = B<-fno-pic> B<-fpic/-fPIC> + (no option) = (no option) B<-fPIC> + B<-fPIE> = B<-fPIE> B<-fpic> + B<-fPIE> = B<-fpie> B<-fPIC/-fpic> + B<-fpie> = B<-fpie> Certain ABI-changing flags are required to match in all compilation units, and trying to override this at link time with a conflicting value is ignored. This includes options such as -freg-struct-return and -fpcc-struct-return. Other options such as -ffp-contract, -fno-strict-overflow, -fwrapv, -fno-trapv or -fno-strict-aliasing are passed through to the link stage and merged conservatively for conflicting translation units. Specifically -fno-strict-overflow, -fwrapv and -fno-trapv take precedence; and for example -ffp-contract=off takes precedence over -ffp-contract=fast. You can override them at link time. Diagnostic options such as -Wstringop-overflow are passed through to the link stage and their setting matches that of the compile-step at function granularity. Note that this matters only for diagnostics emitted during optimization. Note that code transforms such as inlining can lead to warnings being enabled or disabled for regions if code not consistent with the setting at compile time. When you need to pass options to the assembler via -Wa or -Xassembler make sure to either compile such translation units with -fno-lto or consistently use the same assembler options on all translation units. You can alternatively also specify assembler options at LTO link time. To enable debug info generation you need to supply -g at compile time. If any of the input files at link time were built with debug info generation enabled the link will enable debug info generation as well. Any elaborate debug info settings like the dwarf level -gdwarf-5 need to be explicitly repeated at the linker command line and mixing different settings in different translation units is discouraged. If LTO encounters objects with C linkage declared with incompatible types in separate translation units to be linked together (undefined behavior according to ISO C99 6.2.7), a non-fatal diagnostic may be issued. The behavior is still undefined at run time. Similar diagnostics may be raised for other languages. Another feature of LTO is that it is possible to apply interprocedural optimizations on files written in different languages: gcc -c -flto foo.c g++ -c -flto bar.cc gfortran -c -flto baz.f90 g++ -o myprog -flto -O3 foo.o bar.o baz.o -lgfortran Notice that the final link is done with g++ to get the C++ runtime libraries and -lgfortran is added to get the Fortran runtime libraries. In general, when mixing languages in LTO mode, you should use the same link command options as when mixing languages in a regular (non-LTO) compilation. If object files containing GIMPLE bytecode are stored in a library archive, say libfoo.a, it is possible to extract and use them in an LTO link if you are using a linker with plugin support. To create static libraries suitable for LTO, use gcc-ar and gcc-ranlib instead of ar and ranlib; to show the symbols of object files with GIMPLE bytecode, use gcc-nm. Those commands require that ar, ranlib and nm have been compiled with plugin support. At link time, use the flag -fuse-linker-plugin to ensure that the library participates in the LTO optimization process: gcc -o myprog -O2 -flto -fuse-linker-plugin a.o b.o -lfoo With the linker plugin enabled, the linker extracts the needed GIMPLE files from libfoo.a and passes them on to the running GCC to make them part of the aggregated GIMPLE image to be optimized. If you are not using a linker with plugin support and/or do not enable the linker plugin, then the objects inside libfoo.a are extracted and linked as usual, but they do not participate in the LTO optimization process. In order to make a static library suitable for both LTO optimization and usual linkage, compile its object files with -flto -ffat-lto-objects. Link-time optimizations do not require the presence of the whole program to operate. If the program does not require any symbols to be exported, it is possible to combine -flto and -fwhole-program to allow the interprocedural optimizers to use more aggressive assumptions which may lead to improved optimization opportunities. Use of -fwhole-program is not needed when linker plugin is active (see -fuse-linker-plugin). The current implementation of LTO makes no attempt to generate bytecode that is portable between different types of hosts. The bytecode files are versioned and there is a strict version check, so bytecode files generated in one version of GCC do not work with an older or newer version of GCC. Link-time optimization does not work well with generation of debugging information on systems other than those using a combination of ELF and DWARF. If you specify the optional n, the optimization and code generation done at link time is executed in parallel using n parallel jobs by utilizing an installed make program. The environment variable MAKE may be used to override the program used. You can also specify -flto=jobserver to use GNU make's job server mode to determine the number of parallel jobs. This is useful when the Makefile calling GCC is already executing in parallel. You must prepend a + to the command recipe in the parent Makefile for this to work. This option likely only works if MAKE is GNU make. Even without the option value, GCC tries to automatically detect a running GNU make's job server. Use -flto=auto to use GNU make's job server, if available, or otherwise fall back to autodetection of the number of CPU threads present in your system."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the partitioning algorithm used by the link-time optimizer. The value is either 1to1 to specify a partitioning mirroring the original source files or balanced to specify partitioning into equally sized chunks (whenever possible) or max to create new partition for every symbol where possible. Specifying none as an algorithm disables partitioning and streaming completely. The default value is balanced. While 1to1 can be used as an workaround for various code ordering issues, the max partitioning is intended for internal testing only. The value one specifies that exactly one partition should be used while the value none bypasses partitioning and executes the link-time optimization step directly from the WPA phase."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option specifies the level of compression used for intermediate language written to LTO object files, and is only meaningful in conjunction with LTO mode (-flto). GCC currently supports two LTO compression algorithms. For zstd, valid values are 0 (no compression) to 19 (maximum compression), while zlib supports values from 0 to 9. Values outside this range are clamped to either minimum or maximum of the supported values. If the option is not given, a default balanced compression setting is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enables the use of a linker plugin during link-time optimization. This option relies on plugin support in the linker, which is available in gold or in GNU ld 2.21 or newer. This option enables the extraction of object files with GIMPLE bytecode out of library archives. This improves the quality of optimization by exposing more code to the link- time optimizer. This information specifies what symbols can be accessed externally (by non-LTO object or during dynamic linking). Resulting code quality improvements on binaries (and shared libraries that use hidden visibility) are similar to -fwhole-program. See -flto for a description of the effect of this flag and how to use it. This option is enabled by default when LTO support in GCC is enabled and GCC was configured for use with a linker supporting plugins (GNU ld 2.21 or newer or gold)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Fat LTO objects are object files that contain both the intermediate language and the object code. This makes them usable for both LTO linking and normal linking. This option is effective only when compiling with -flto and is ignored at link time. -fno-fat-lto-objects improves compilation time over plain LTO, but requires the complete toolchain to be aware of LTO. It requires a linker with linker plugin support for basic functionality. Additionally, nm, ar and ranlib need to support linker plugins to allow a full-featured build environment (capable of building static libraries etc). GCC provides the gcc-ar, gcc-nm, gcc-ranlib wrappers to pass the right options to these tools. With non fat LTO makefiles need to be modified to use them. Note that modern binutils provide plugin auto-load mechanism. Installing the linker plugin into $libdir/bfd-plugins has the same effect as usage of the command wrappers (gcc-ar, gcc-nm and gcc-ranlib). The default is -fno-fat-lto-objects on targets with linker plugin support."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "After register allocation and post-register allocation instruction splitting, identify arithmetic instructions that compute processor flags similar to a comparison operation based on that arithmetic. If possible, eliminate the explicit comparison operation. This pass only applies to certain targets that cannot explicitly represent the comparison operation before register allocation is complete. Enabled at levels -O1, -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "After register allocation and post-register allocation instruction splitting, perform a copy-propagation pass to try to reduce scheduling dependencies and occasionally eliminate the copy. Enabled at levels -O1, -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Profiles collected using an instrumented binary for multi-threaded programs may be inconsistent due to missed counter updates. When this option is specified, GCC uses heuristics to correct or smooth out such inconsistencies. By default, GCC emits an error message when an inconsistent profile is detected. This option is enabled by -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With \"-fprofile-use\" all portions of programs not executed during train run are optimized agressively for size rather than speed. In some cases it is not practical to train all possible hot paths in the program. (For example, program may contain functions specific for a given hardware and trianing may not cover all hardware configurations program is run on.) With \"-fprofile-partial-training\" profile feedback will be ignored for all functions not executed during the train run leading them to be optimized as if they were compiled without profile feedback. This leads to better performance when train run is not representative but also leads to significantly bigger code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable profile feedback-directed optimizations, and the following optimizations, many of which are generally profitable only with profile feedback available: -fbranch-probabilities -fprofile-values -funroll-loops -fpeel-loops -ftracer -fvpt -finline-functions -fipa-cp -fipa-cp-clone -fipa-bit-cp -fpredictive-commoning -fsplit-loops -funswitch-loops -fgcse-after-reload -ftree-loop-vectorize -ftree-slp-vectorize -fvect-cost-model=dynamic -ftree-loop-distribute-patterns -fprofile-reorder-functions Before you can use this option, you must first generate profiling information. By default, GCC emits an error message if the feedback profiles do not match the source code. This error can be turned into a warning by using -Wno-error=coverage-mismatch. Note this may result in poorly optimized code. Additionally, by default, GCC also emits a warning message if the feedback profiles do not exist (see -Wmissing-profile). If path is specified, GCC looks at the path to find the profile feedback data files. See -fprofile-dir."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable sampling-based feedback-directed optimizations, and the following optimizations, many of which are generally profitable only with profile feedback available: -fbranch-probabilities -fprofile-values -funroll-loops -fpeel-loops -ftracer -fvpt -finline-functions -fipa-cp -fipa-cp-clone -fipa-bit-cp -fpredictive-commoning -fsplit-loops -funswitch-loops -fgcse-after-reload -ftree-loop-vectorize -ftree-slp-vectorize -fvect-cost-model=dynamic -ftree-loop-distribute-patterns -fprofile-correction path is the name of a file containing AutoFDO profile information. If omitted, it defaults to fbdata.afdo in the current directory. Producing an AutoFDO profile data file requires running your program with the perf utility on a supported GNU/Linux target system. For more information, see <https://perf.wiki.kernel.org/>. E.g. perf record -e brinstretired:neartaken -b -o perf.data \\ -- yourprogram Then use the creategcov tool to convert the raw profile data to a format that can be used by GCC. You must also supply the unstripped binary for your program to this tool. See <https://github.com/google/autofdo>. E.g. creategcov --binary=yourprogram.unstripped --profile=perf.data \\ --gcov=profile.afdo The following options control compiler behavior regarding floating-point arithmetic. These options trade off between speed and correctness. All must be specifically enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not store floating-point variables in registers, and inhibit other options that might change whether a floating-point value is taken from a register or memory. This option prevents undesirable excess precision on machines such as the 68000 where the floating registers (of the 68881) keep more precision than a \"double\" is supposed to have. Similarly for the x86 architecture. For most programs, the excess precision does only good, but a few programs rely on the precise definition of IEEE floating point. Use -ffloat-store for such programs, after modifying them to store all pertinent intermediate computations into variables."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option allows further control over excess precision on machines where floating-point operations occur in a format with more precision or range than the IEEE standard and interchange floating-point types. By default, -fexcess-precision=fast is in effect; this means that operations may be carried out in a wider precision than the types specified in the source if that would result in faster code, and it is unpredictable when rounding to the types specified in the source code takes place. When compiling C or C++, if -fexcess-precision=standard is specified then excess precision follows the rules specified in ISO C99 or C++; in particular, both casts and assignments cause values to be rounded to their semantic types (whereas -ffloat-store only affects assignments). This option is enabled by default for C or C++ if a strict conformance option such as -std=c99 or -std=c++17 is used. -ffast-math enables -fexcess-precision=fast by default regardless of whether a strict conformance option is used. -fexcess-precision=standard is not implemented for languages other than C or C++. On the x86, it has no effect if -mfpmath=sse or -mfpmath=sse+387 is specified; in the former case, IEEE semantics apply without excess precision, and in the latter, rounding is unpredictable."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Sets the options -fno-math-errno, -funsafe-math-optimizations, -ffinite-math-only, -fno-rounding-math, -fno-signaling-nans, -fcx-limited-range and -fexcess-precision=fast. This option causes the preprocessor macro \"FASTMATH\" to be defined. This option is not turned on by any -O option besides -Ofast since it can result in incorrect output for programs that depend on an exact implementation of IEEE or ISO rules/specifications for math functions. It may, however, yield faster code for programs that do not require the guarantees of these specifications."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not set \"errno\" after calling math functions that are executed with a single instruction, e.g., \"sqrt\". A program that relies on IEEE exceptions for math error handling may want to use this flag for speed while maintaining IEEE arithmetic compatibility. This option is not turned on by any -O option since it can result in incorrect output for programs that depend on an exact implementation of IEEE or ISO rules/specifications for math functions. It may, however, yield faster code for programs that do not require the guarantees of these specifications. The default is -fmath-errno. On Darwin systems, the math library never sets \"errno\". There is therefore no reason for the compiler to consider the possibility that it might, and -fno-math-errno is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow optimizations for floating-point arithmetic that (a) assume that arguments and results are valid and (b) may violate IEEE or ANSI standards. When used at link time, it may include libraries or startup files that change the default FPU control word or other similar optimizations. This option is not turned on by any -O option since it can result in incorrect output for programs that depend on an exact implementation of IEEE or ISO rules/specifications for math functions. It may, however, yield faster code for programs that do not require the guarantees of these specifications. Enables -fno-signed-zeros, -fno-trapping-math, -fassociative-math and -freciprocal-math. The default is -fno-unsafe-math-optimizations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow re-association of operands in series of floating-point operations. This violates the ISO C and C++ language standard by possibly changing computation result. NOTE: re- ordering may change the sign of zero as well as ignore NaNs and inhibit or create underflow or overflow (and thus cannot be used on code that relies on rounding behavior like \"(x + 252) - 252\". May also reorder floating-point comparisons and thus may not be used when ordered comparisons are required. This option requires that both -fno-signed-zeros and -fno-trapping-math be in effect. Moreover, it doesn't make much sense with -frounding-math. For Fortran the option is automatically enabled when both -fno-signed-zeros and -fno-trapping-math are in effect. The default is -fno-associative-math."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow the reciprocal of a value to be used instead of dividing by the value if this enables optimizations. For example \"x / y\" can be replaced with \"x * (1/y)\", which is useful if \"(1/y)\" is subject to common subexpression elimination. Note that this loses precision and increases the number of flops operating on the value. The default is -fno-reciprocal-math."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow optimizations for floating-point arithmetic that assume that arguments and results are not NaNs or +-Infs. This option is not turned on by any -O option since it can result in incorrect output for programs that depend on an exact implementation of IEEE or ISO rules/specifications for math functions. It may, however, yield faster code for programs that do not require the guarantees of these specifications. The default is -fno-finite-math-only."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow optimizations for floating-point arithmetic that ignore the signedness of zero. IEEE arithmetic specifies the behavior of distinct +0.0 and -0.0 values, which then prohibits simplification of expressions such as x+0.0 or 0.0*x (even with -ffinite-math-only). This option implies that the sign of a zero result isn't significant. The default is -fsigned-zeros."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Compile code assuming that floating-point operations cannot generate user-visible traps. These traps include division by zero, overflow, underflow, inexact result and invalid operation. This option requires that -fno-signaling-nans be in effect. Setting this option may allow faster code if one relies on \"non-stop\" IEEE arithmetic, for example. This option should never be turned on by any -O option since it can result in incorrect output for programs that depend on an exact implementation of IEEE or ISO rules/specifications for math functions. The default is -ftrapping-math. Future versions of GCC may provide finer control of this setting using C99's \"FENVACCESS\" pragma. This command-line option will be used along with -frounding-math to specify the default state for \"FENVACCESS\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable transformations and optimizations that assume default floating-point rounding behavior. This is round-to-zero for all floating point to integer conversions, and round-to-nearest for all other arithmetic truncations. This option should be specified for programs that change the FP rounding mode dynamically, or that may be executed with a non-default rounding mode. This option disables constant folding of floating-point expressions at compile time (which may be affected by rounding mode) and arithmetic transformations that are unsafe in the presence of sign-dependent rounding modes. The default is -fno-rounding-math. This option is experimental and does not currently guarantee to disable all GCC optimizations that are affected by rounding mode. Future versions of GCC may provide finer control of this setting using C99's \"FENVACCESS\" pragma. This command-line option will be used along with -ftrapping-math to specify the default state for \"FENVACCESS\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Compile code assuming that IEEE signaling NaNs may generate user-visible traps during floating-point operations. Setting this option disables optimizations that may change the number of exceptions visible with signaling NaNs. This option implies -ftrapping-math. This option causes the preprocessor macro \"SUPPORTSNAN\" to be defined. The default is -fno-signaling-nans. This option is experimental and does not currently guarantee to disable all GCC optimizations that affect signaling NaN behavior."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not allow the built-in functions \"ceil\", \"floor\", \"round\" and \"trunc\", and their \"float\" and \"long double\" variants, to generate code that raises the \"inexact\" floating- point exception for noninteger arguments. ISO C99 and C11 allow these functions to raise the \"inexact\" exception, but ISO/IEC TS 18661-1:2014, the C bindings to IEEE 754-2008, as integrated into ISO C2X, does not allow these functions to do so. The default is -ffp-int-builtin-inexact, allowing the exception to be raised, unless C2X or a later C standard is selected. This option does nothing unless -ftrapping-math is in effect. Even if -fno-fp-int-builtin-inexact is used, if the functions generate a call to a library function then the \"inexact\" exception may be raised if the library implementation does not follow TS 18661."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Treat floating-point constants as single precision instead of implicitly converting them to double-precision constants."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When enabled, this option states that a range reduction step is not needed when performing complex division. Also, there is no checking whether the result of a complex multiplication or division is \"NaN + I*NaN\", with an attempt to rescue the situation in that case. The default is -fno-cx-limited-range, but is enabled by -ffast-math. This option controls the default setting of the ISO C99 \"CXLIMITEDRANGE\" pragma. Nevertheless, the option applies to all languages."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Complex multiplication and division follow Fortran rules. Range reduction is done as part of complex division, but there is no checking whether the result of a complex multiplication or division is \"NaN + I*NaN\", with an attempt to rescue the situation in that case. The default is -fno-cx-fortran-rules. The following options control optimizations that may improve performance, but are not enabled by any -O options. This section includes experimental options that may produce broken code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "After running a program compiled with -fprofile-arcs, you can compile it a second time using -fbranch-probabilities, to improve optimizations based on the number of times each branch was taken. When a program compiled with -fprofile-arcs exits, it saves arc execution counts to a file called sourcename.gcda for each source file. The information in this data file is very dependent on the structure of the generated code, so you must use the same source code and the same optimization options for both compilations. See details about the file naming in -fprofile-arcs. With -fbranch-probabilities, GCC puts a REGBRPROB note on each JUMPINSN and CALLINSN. These can be used to improve optimization. Currently, they are only used in one place: in reorg.cc, instead of guessing which path a branch is most likely to take, the REGBRPROB values are used to exactly determine which path is taken more often. Enabled by -fprofile-use and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If combined with -fprofile-arcs, it adds code so that some data about values of expressions in the program is gathered. With -fbranch-probabilities, it reads back the data gathered from profiling values of expressions for usage in optimizations. Enabled by -fprofile-generate, -fprofile-use, and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Function reordering based on profile instrumentation collects first time of execution of a function and orders these functions in ascending order. Enabled with -fprofile-use."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If combined with -fprofile-arcs, this option instructs the compiler to add code to gather information about values of expressions. With -fbranch-probabilities, it reads back the data gathered and actually performs the optimizations based on them. Currently the optimizations include specialization of division operations using the knowledge about the value of the denominator. Enabled with -fprofile-use and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Attempt to avoid false dependencies in scheduled code by making use of registers left over after register allocation. This optimization most benefits processors with lots of registers. Depending on the debug information format adopted by the target, however, it can make debugging impossible, since variables no longer stay in a \"home register\". Enabled by default with -funroll-loops."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Performs a target dependent pass over the instruction stream to schedule instructions of same type together because target machine can execute them more efficiently if they are adjacent to each other in the instruction flow. Enabled at levels -O2, -O3, -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform tail duplication to enlarge superblock size. This transformation simplifies the control flow of the function allowing other optimizations to do a better job. Enabled by -fprofile-use and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Unroll loops whose number of iterations can be determined at compile time or upon entry to the loop. -funroll-loops implies -frerun-cse-after-loop, -fweb and -frename-registers. It also turns on complete loop peeling (i.e. complete removal of loops with a small constant number of iterations). This option makes code larger, and may or may not make it run faster. Enabled by -fprofile-use and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Unroll all loops, even if their number of iterations is uncertain when the loop is entered. This usually makes programs run more slowly. -funroll-all-loops implies the same options as -funroll-loops."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Peels loops for which there is enough information that they do not roll much (from profile feedback or static analysis). It also turns on complete loop peeling (i.e. complete removal of loops with small constant number of iterations). Enabled by -O3, -fprofile-use, and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enables the loop invariant motion pass in the RTL loop optimizer. Enabled at level -O1 and higher, except for -Og."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enables the loop store motion pass in the GIMPLE loop optimizer. This moves invariant stores to after the end of the loop in exchange for carrying the stored value in a register across the iteration. Note for this option to have an effect -ftree-loop-im has to be enabled as well. Enabled at level -O1 and higher, except for -Og."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Split a loop into two if it contains a condition that's always true for one side of the iteration space and false for the other. Enabled by -fprofile-use and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Move branches with loop invariant conditions out of the loop, with duplicates of the loop on both branches (modified according to result of the condition). Enabled by -fprofile-use and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If a loop iterates over an array with a variable stride, create another version of the loop that assumes the stride is always one. For example: for (int i = 0; i < n; ++i) x[i * stride] = ...; becomes: if (stride == 1) for (int i = 0; i < n; ++i) x[i] = ...; else for (int i = 0; i < n; ++i) x[i * stride] = ...; This is particularly useful for assumed-shape arrays in Fortran where (for example) it allows better vectorization assuming contiguous accesses. This flag is enabled by default at -O3. It is also enabled by -fprofile-use and -fauto-profile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Place each function or data item into its own section in the output file if the target supports arbitrary sections. The name of the function or the name of the data item determines the section's name in the output file. Use these options on systems where the linker can perform optimizations to improve locality of reference in the instruction space. Most systems using the ELF object format have linkers with such optimizations. On AIX, the linker rearranges sections (CSECTs) based on the call graph. The performance impact varies. Together with a linker garbage collection (linker --gc-sections option) these options may lead to smaller statically-linked executables (after stripping). On ELF/DWARF systems these options do not degenerate the quality of the debug information. There could be issues with other object files/debug info formats. Only use these options when there are significant benefits from doing so. When you specify these options, the assembler and linker create larger object and executable files and are also slower. These options affect code generation. They prevent optimizations by the compiler and assembler using relative locations inside a translation unit since the locations are unknown until link time. An example of such an optimization is relaxing calls to short call instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Optimize the prologue of variadic argument functions with respect to usage of those arguments."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Try to reduce the number of symbolic address calculations by using shared \"anchor\" symbols to address nearby objects. This transformation can help to reduce the number of GOT entries and GOT accesses on some targets. For example, the implementation of the following function \"foo\": static int a, b, c; int foo (void) { return a + b + c; } usually calculates the addresses of all three variables, but if you compile it with -fsection-anchors, it accesses the variables from a common anchor point instead. The effect is similar to the following pseudocode (which isn't valid C): int foo (void) { register int *xr = &x; return xr[&a - &x] + xr[&b - &x] + xr[&c - &x]; } Not all targets support this option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Zero call-used registers at function return to increase program security by either mitigating Return-Oriented Programming (ROP) attacks or preventing information leakage through registers. The possible values of choice are the same as for the \"zerocallusedregs\" attribute. The default is skip. You can control this behavior for a specific function by using the function attribute \"zerocallusedregs\". --param name=value In some places, GCC uses various constants to control the amount of optimization that is done. For example, GCC does not inline functions that contain more than a certain number of instructions. You can control some of these constants on the command line using the --param option. The names of specific parameters, and the meaning of the values, are tied to the internals of the compiler, and are subject to change without notice in future releases. In order to get the minimal, maximal and default values of a parameter, use the --help=param -Q options. In each case, the value is an integer. The following choices of name are recognized for all targets: predictable-branch-outcome When branch is predicted to be taken with probability lower than this threshold (in percent), then it is considered well predictable. max-rtl-if-conversion-insns RTL if-conversion tries to remove conditional branches around a block and replace them with conditionally executed instructions. This parameter gives the maximum number of instructions in a block which should be considered for if-conversion. The compiler will also use other heuristics to decide whether if-conversion is likely to be profitable. max-rtl-if-conversion-predictable-cost RTL if-conversion will try to remove conditional branches around a block and replace them with conditionally executed instructions. These parameters give the maximum permissible cost for the sequence that would be generated by if-conversion depending on whether the branch is statically determined to be predictable or not. The units for this parameter are the same as those for the GCC internal seqcost metric. The compiler will try to provide a reasonable default for this parameter using the BRANCHCOST target macro. max-crossjump-edges The maximum number of incoming edges to consider for cross-jumping. The algorithm used by -fcrossjumping is O(N^2) in the number of edges incoming to each block. Increasing values mean more aggressive optimization, making the compilation time increase with probably small improvement in executable size. min-crossjump-insns The minimum number of instructions that must be matched at the end of two blocks before cross-jumping is performed on them. This value is ignored in the case where all instructions in the block being cross-jumped from are matched. max-grow-copy-bb-insns The maximum code size expansion factor when copying basic blocks instead of jumping. The expansion is relative to a jump instruction. max-goto-duplication-insns The maximum number of instructions to duplicate to a block that jumps to a computed goto. To avoid O(N^2) behavior in a number of passes, GCC factors computed gotos early in the compilation process, and unfactors them as late as possible. Only computed jumps at the end of a basic blocks with no more than max-goto-duplication- insns are unfactored. max-delay-slot-insn-search The maximum number of instructions to consider when looking for an instruction to fill a delay slot. If more than this arbitrary number of instructions are searched, the time savings from filling the delay slot are minimal, so stop searching. Increasing values mean more aggressive optimization, making the compilation time increase with probably small improvement in execution time. max-delay-slot-live-search When trying to fill delay slots, the maximum number of instructions to consider when searching for a block with valid live register information. Increasing this arbitrarily chosen value means more aggressive optimization, increasing the compilation time. This parameter should be removed when the delay slot code is rewritten to maintain the control-flow graph. max-gcse-memory The approximate maximum amount of memory in \"kB\" that can be allocated in order to perform the global common subexpression elimination optimization. If more memory than specified is required, the optimization is not done. max-gcse-insertion-ratio If the ratio of expression insertions to deletions is larger than this value for any expression, then RTL PRE inserts or removes the expression and thus leaves partially redundant computations in the instruction stream. max-pending-list-length The maximum number of pending dependencies scheduling allows before flushing the current state and starting over. Large functions with few branches or calls can create excessively large lists which needlessly consume memory and resources. max-modulo-backtrack-attempts The maximum number of backtrack attempts the scheduler should make when modulo scheduling a loop. Larger values can exponentially increase compilation time. max-inline-functions-called-once-loop-depth Maximal loop depth of a call considered by inline heuristics that tries to inline all functions called once. max-inline-functions-called-once-insns Maximal estimated size of functions produced while inlining functions called once. max-inline-insns-single Several parameters control the tree inliner used in GCC. This number sets the maximum number of instructions (counted in GCC's internal representation) in a single function that the tree inliner considers for inlining. This only affects functions declared inline and methods implemented in a class declaration (C++). max-inline-insns-auto When you use -finline-functions (included in -O3), a lot of functions that would otherwise not be considered for inlining by the compiler are investigated. To those functions, a different (more restrictive) limit compared to functions declared inline can be applied (--param max-inline-insns-auto). max-inline-insns-small This is bound applied to calls which are considered relevant with -finline-small-functions. max-inline-insns-size This is bound applied to calls which are optimized for size. Small growth may be desirable to anticipate optimization oppurtunities exposed by inlining. uninlined-function-insns Number of instructions accounted by inliner for function overhead such as function prologue and epilogue. uninlined-function-time Extra time accounted by inliner for function overhead such as time needed to execute function prologue and epilogue. inline-heuristics-hint-percent The scale (in percents) applied to inline-insns-single, inline-insns-single-O2, inline-insns-auto when inline heuristics hints that inlining is very profitable (will enable later optimizations). uninlined-thunk-insns uninlined-thunk-time Same as --param uninlined-function-insns and --param uninlined-function-time but applied to function thunks. inline-min-speedup When estimated performance improvement of caller + callee runtime exceeds this threshold (in percent), the function can be inlined regardless of the limit on --param max-inline-insns-single and --param max-inline-insns-auto. large-function-insns The limit specifying really large functions. For functions larger than this limit after inlining, inlining is constrained by --param large-function-growth. This parameter is useful primarily to avoid extreme compilation time caused by non-linear algorithms used by the back end. large-function-growth Specifies maximal growth of large function caused by inlining in percents. For example, parameter value 100 limits large function growth to 2.0 times the original size. large-unit-insns The limit specifying large translation unit. Growth caused by inlining of units larger than this limit is limited by --param inline-unit-growth. For small units this might be too tight. For example, consider a unit consisting of function A that is inline and B that just calls A three times. If B is small relative to A, the growth of unit is 300\\% and yet such inlining is very sane. For very large units consisting of small inlineable functions, however, the overall unit growth limit is needed to avoid exponential explosion of code size. Thus for smaller units, the size is increased to --param large-unit-insns before applying --param inline-unit-growth. lazy-modules Maximum number of concurrently open C++ module files when lazy loading. inline-unit-growth Specifies maximal overall growth of the compilation unit caused by inlining. For example, parameter value 20 limits unit growth to 1.2 times the original size. Cold functions (either marked cold via an attribute or by profile feedback) are not accounted into the unit size. ipa-cp-unit-growth Specifies maximal overall growth of the compilation unit caused by interprocedural constant propagation. For example, parameter value 10 limits unit growth to 1.1 times the original size. ipa-cp-large-unit-insns The size of translation unit that IPA-CP pass considers large. large-stack-frame The limit specifying large stack frames. While inlining the algorithm is trying to not grow past this limit too much. large-stack-frame-growth Specifies maximal growth of large stack frames caused by inlining in percents. For example, parameter value 1000 limits large stack frame growth to 11 times the original size. max-inline-insns-recursive max-inline-insns-recursive-auto Specifies the maximum number of instructions an out-of-line copy of a self-recursive inline function can grow into by performing recursive inlining. --param max-inline-insns-recursive applies to functions declared inline. For functions not declared inline, recursive inlining happens only when -finline-functions (included in -O3) is enabled; --param max-inline-insns-recursive- auto applies instead. max-inline-recursive-depth max-inline-recursive-depth-auto Specifies the maximum recursion depth used for recursive inlining. --param max-inline-recursive-depth applies to functions declared inline. For functions not declared inline, recursive inlining happens only when -finline-functions (included in -O3) is enabled; --param max-inline-recursive-depth- auto applies instead. min-inline-recursive-probability Recursive inlining is profitable only for function having deep recursion in average and can hurt for function having little recursion depth by increasing the prologue size or complexity of function body to other optimizers. When profile feedback is available (see -fprofile-generate) the actual recursion depth can be guessed from the probability that function recurses via a given call expression. This parameter limits inlining only to call expressions whose probability exceeds the given threshold (in percents). early-inlining-insns Specify growth that the early inliner can make. In effect it increases the amount of inlining for code having a large abstraction penalty. max-early-inliner-iterations Limit of iterations of the early inliner. This basically bounds the number of nested indirect calls the early inliner can resolve. Deeper chains are still handled by late inlining. comdat-sharing-probability Probability (in percent) that C++ inline function with comdat visibility are shared across multiple compilation units. modref-max-bases modref-max-refs modref-max-accesses Specifies the maximal number of base pointers, references and accesses stored for a single function by mod/ref analysis. modref-max-tests Specifies the maxmal number of tests alias oracle can perform to disambiguate memory locations using the mod/ref information. This parameter ought to be bigger than --param modref-max-bases and --param modref-max-refs. modref-max-depth Specifies the maximum depth of DFS walk used by modref escape analysis. Setting to 0 disables the analysis completely. modref-max-escape-points Specifies the maximum number of escape points tracked by modref per SSA-name. modref-max-adjustments Specifies the maximum number the access range is enlarged during modref dataflow analysis. profile-func-internal-id A parameter to control whether to use function internal id in profile database lookup. If the value is 0, the compiler uses an id that is based on function assembler name and filename, which makes old profile data more tolerant to source changes such as function reordering etc. min-vect-loop-bound The minimum number of iterations under which loops are not vectorized when -ftree-vectorize is used. The number of iterations after vectorization needs to be greater than the value specified by this option to allow vectorization. gcse-cost-distance-ratio Scaling factor in calculation of maximum distance an expression can be moved by GCSE optimizations. This is currently supported only in the code hoisting pass. The bigger the ratio, the more aggressive code hoisting is with simple expressions, i.e., the expressions that have cost less than gcse-unrestricted-cost. Specifying 0 disables hoisting of simple expressions. gcse-unrestricted-cost Cost, roughly measured as the cost of a single typical machine instruction, at which GCSE optimizations do not constrain the distance an expression can travel. This is currently supported only in the code hoisting pass. The lesser the cost, the more aggressive code hoisting is. Specifying 0 allows all expressions to travel unrestricted distances. max-hoist-depth The depth of search in the dominator tree for expressions to hoist. This is used to avoid quadratic behavior in hoisting algorithm. The value of 0 does not limit on the search, but may slow down compilation of huge functions. max-tail-merge-comparisons The maximum amount of similar bbs to compare a bb with. This is used to avoid quadratic behavior in tree tail merging. max-tail-merge-iterations The maximum amount of iterations of the pass over the function. This is used to limit compilation time in tree tail merging. store-merging-allow-unaligned Allow the store merging pass to introduce unaligned stores if it is legal to do so. max-stores-to-merge The maximum number of stores to attempt to merge into wider stores in the store merging pass. max-store-chains-to-track The maximum number of store chains to track at the same time in the attempt to merge them into wider stores in the store merging pass. max-stores-to-track The maximum number of stores to track at the same time in the attemt to to merge them into wider stores in the store merging pass. max-unrolled-insns The maximum number of instructions that a loop may have to be unrolled. If a loop is unrolled, this parameter also determines how many times the loop code is unrolled. max-average-unrolled-insns The maximum number of instructions biased by probabilities of their execution that a loop may have to be unrolled. If a loop is unrolled, this parameter also determines how many times the loop code is unrolled. max-unroll-times The maximum number of unrollings of a single loop. max-peeled-insns The maximum number of instructions that a loop may have to be peeled. If a loop is peeled, this parameter also determines how many times the loop code is peeled. max-peel-times The maximum number of peelings of a single loop. max-peel-branches The maximum number of branches on the hot path through the peeled sequence. max-completely-peeled-insns The maximum number of insns of a completely peeled loop. max-completely-peel-times The maximum number of iterations of a loop to be suitable for complete peeling. max-completely-peel-loop-nest-depth The maximum depth of a loop nest suitable for complete peeling. max-unswitch-insns The maximum number of insns of an unswitched loop. max-unswitch-depth The maximum depth of a loop nest to be unswitched. lim-expensive The minimum cost of an expensive expression in the loop invariant motion. min-loop-cond-split-prob When FDO profile information is available, min-loop-cond-split-prob specifies minimum threshold for probability of semi-invariant condition statement to trigger loop split. iv-consider-all-candidates-bound Bound on number of candidates for induction variables, below which all candidates are considered for each use in induction variable optimizations. If there are more candidates than this, only the most relevant ones are considered to avoid quadratic time complexity. iv-max-considered-uses The induction variable optimizations give up on loops that contain more induction variable uses. iv-always-prune-cand-set-bound If the number of candidates in the set is smaller than this value, always try to remove unnecessary ivs from the set when adding a new one. avg-loop-niter Average number of iterations of a loop. dse-max-object-size Maximum size (in bytes) of objects tracked bytewise by dead store elimination. Larger values may result in larger compilation times. dse-max-alias-queries-per-store Maximum number of queries into the alias oracle per store. Larger values result in larger compilation times and may result in more removed dead stores. scev-max-expr-size Bound on size of expressions used in the scalar evolutions analyzer. Large expressions slow the analyzer. scev-max-expr-complexity Bound on the complexity of the expressions in the scalar evolutions analyzer. Complex expressions slow the analyzer. max-tree-if-conversion-phi-args Maximum number of arguments in a PHI supported by TREE if conversion unless the loop is marked with simd pragma. vect-max-layout-candidates The maximum number of possible vector layouts (such as permutations) to consider when optimizing to-be-vectorized code. vect-max-version-for-alignment-checks The maximum number of run-time checks that can be performed when doing loop versioning for alignment in the vectorizer. vect-max-version-for-alias-checks The maximum number of run-time checks that can be performed when doing loop versioning for alias in the vectorizer. vect-max-peeling-for-alignment The maximum number of loop peels to enhance access alignment for vectorizer. Value -1 means no limit. max-iterations-to-track The maximum number of iterations of a loop the brute-force algorithm for analysis of the number of iterations of the loop tries to evaluate. hot-bb-count-fraction The denominator n of fraction 1/n of the maximal execution count of a basic block in the entire program that a basic block needs to at least have in order to be considered hot. The default is 10000, which means that a basic block is considered hot if its execution count is greater than 1/10000 of the maximal execution count. 0 means that it is never considered hot. Used in non-LTO mode. hot-bb-count-ws-permille The number of most executed permilles, ranging from 0 to 1000, of the profiled execution of the entire program to which the execution count of a basic block must be part of in order to be considered hot. The default is 990, which means that a basic block is considered hot if its execution count contributes to the upper 990 permilles, or 99.0%, of the profiled execution of the entire program. 0 means that it is never considered hot. Used in LTO mode. hot-bb-frequency-fraction The denominator n of fraction 1/n of the execution frequency of the entry block of a function that a basic block of this function needs to at least have in order to be considered hot. The default is 1000, which means that a basic block is considered hot in a function if it is executed more frequently than 1/1000 of the frequency of the entry block of the function. 0 means that it is never considered hot. unlikely-bb-count-fraction The denominator n of fraction 1/n of the number of profiled runs of the entire program below which the execution count of a basic block must be in order for the basic block to be considered unlikely executed. The default is 20, which means that a basic block is considered unlikely executed if it is executed in fewer than 1/20, or 5%, of the runs of the program. 0 means that it is always considered unlikely executed. max-predicted-iterations The maximum number of loop iterations we predict statically. This is useful in cases where a function contains a single loop with known bound and another loop with unknown bound. The known number of iterations is predicted correctly, while the unknown number of iterations average to roughly 10. This means that the loop without bounds appears artificially cold relative to the other one. builtin-expect-probability Control the probability of the expression having the specified value. This parameter takes a percentage (i.e. 0 ... 100) as input. builtin-string-cmp-inline-length The maximum length of a constant string for a builtin string cmp call eligible for inlining. align-threshold Select fraction of the maximal frequency of executions of a basic block in a function to align the basic block. align-loop-iterations A loop expected to iterate at least the selected number of iterations is aligned. tracer-dynamic-coverage tracer-dynamic-coverage-feedback This value is used to limit superblock formation once the given percentage of executed instructions is covered. This limits unnecessary code size expansion. The tracer-dynamic-coverage-feedback parameter is used only when profile feedback is available. The real profiles (as opposed to statically estimated ones) are much less balanced allowing the threshold to be larger value. tracer-max-code-growth Stop tail duplication once code growth has reached given percentage. This is a rather artificial limit, as most of the duplicates are eliminated later in cross jumping, so it may be set to much higher values than is the desired code growth. tracer-min-branch-ratio Stop reverse growth when the reverse probability of best edge is less than this threshold (in percent). tracer-min-branch-probability tracer-min-branch-probability-feedback Stop forward growth if the best edge has probability lower than this threshold. Similarly to tracer-dynamic-coverage two parameters are provided. tracer-min-branch- probability-feedback is used for compilation with profile feedback and tracer-min- branch-probability compilation without. The value for compilation with profile feedback needs to be more conservative (higher) in order to make tracer effective. stack-clash-protection-guard-size Specify the size of the operating system provided stack guard as 2 raised to num bytes. Higher values may reduce the number of explicit probes, but a value larger than the operating system provided guard will leave code vulnerable to stack clash style attacks. stack-clash-protection-probe-interval Stack clash protection involves probing stack space as it is allocated. This param controls the maximum distance between probes into the stack as 2 raised to num bytes. Higher values may reduce the number of explicit probes, but a value larger than the operating system provided guard will leave code vulnerable to stack clash style attacks. max-cse-path-length The maximum number of basic blocks on path that CSE considers. max-cse-insns The maximum number of instructions CSE processes before flushing. ggc-min-expand GCC uses a garbage collector to manage its own memory allocation. This parameter specifies the minimum percentage by which the garbage collector's heap should be allowed to expand between collections. Tuning this may improve compilation speed; it has no effect on code generation. The default is 30% + 70% * (RAM/1GB) with an upper bound of 100% when RAM >= 1GB. If \"getrlimit\" is available, the notion of \"RAM\" is the smallest of actual RAM and \"RLIMITDATA\" or \"RLIMITAS\". If GCC is not able to calculate RAM on a particular platform, the lower bound of 30% is used. Setting this parameter and ggc-min- heapsize to zero causes a full collection to occur at every opportunity. This is extremely slow, but can be useful for debugging. ggc-min-heapsize Minimum size of the garbage collector's heap before it begins bothering to collect garbage. The first collection occurs after the heap expands by ggc-min-expand% beyond ggc-min-heapsize. Again, tuning this may improve compilation speed, and has no effect on code generation. The default is the smaller of RAM/8, RLIMITRSS, or a limit that tries to ensure that RLIMITDATA or RLIMITAS are not exceeded, but with a lower bound of 4096 (four megabytes) and an upper bound of 131072 (128 megabytes). If GCC is not able to calculate RAM on a particular platform, the lower bound is used. Setting this parameter very large effectively disables garbage collection. Setting this parameter and ggc-min-expand to zero causes a full collection to occur at every opportunity. max-reload-search-insns The maximum number of instruction reload should look backward for equivalent register. Increasing values mean more aggressive optimization, making the compilation time increase with probably slightly better performance. max-cselib-memory-locations The maximum number of memory locations cselib should take into account. Increasing values mean more aggressive optimization, making the compilation time increase with probably slightly better performance. max-sched-ready-insns The maximum number of instructions ready to be issued the scheduler should consider at any given time during the first scheduling pass. Increasing values mean more thorough searches, making the compilation time increase with probably little benefit. max-sched-region-blocks The maximum number of blocks in a region to be considered for interblock scheduling. max-pipeline-region-blocks The maximum number of blocks in a region to be considered for pipelining in the selective scheduler. max-sched-region-insns The maximum number of insns in a region to be considered for interblock scheduling. max-pipeline-region-insns The maximum number of insns in a region to be considered for pipelining in the selective scheduler. min-spec-prob The minimum probability (in percents) of reaching a source block for interblock speculative scheduling. max-sched-extend-regions-iters The maximum number of iterations through CFG to extend regions. A value of 0 disables region extensions. max-sched-insn-conflict-delay The maximum conflict delay for an insn to be considered for speculative motion. sched-spec-prob-cutoff The minimal probability of speculation success (in percents), so that speculative insns are scheduled. sched-state-edge-prob-cutoff The minimum probability an edge must have for the scheduler to save its state across it. sched-mem-true-dep-cost Minimal distance (in CPU cycles) between store and load targeting same memory locations. selsched-max-lookahead The maximum size of the lookahead window of selective scheduling. It is a depth of search for available instructions. selsched-max-sched-times The maximum number of times that an instruction is scheduled during selective scheduling. This is the limit on the number of iterations through which the instruction may be pipelined. selsched-insns-to-rename The maximum number of best instructions in the ready list that are considered for renaming in the selective scheduler. sms-min-sc The minimum value of stage count that swing modulo scheduler generates. max-last-value-rtl The maximum size measured as number of RTLs that can be recorded in an expression in combiner for a pseudo register as last known value of that register. max-combine-insns The maximum number of instructions the RTL combiner tries to combine. integer-share-limit Small integer constants can use a shared data structure, reducing the compiler's memory usage and increasing its speed. This sets the maximum value of a shared integer constant. ssp-buffer-size The minimum size of buffers (i.e. arrays) that receive stack smashing protection when -fstack-protector is used. This default before Ubuntu 10.10 was \"8\". Currently it is \"4\", to increase the number of functions protected by the stack protector. min-size-for-stack-sharing The minimum size of variables taking part in stack slot sharing when not optimizing. max-jump-thread-duplication-stmts Maximum number of statements allowed in a block that needs to be duplicated when threading jumps. max-jump-thread-paths The maximum number of paths to consider when searching for jump threading opportunities. When arriving at a block, incoming edges are only considered if the number of paths to be searched so far multiplied by the number of incoming edges does not exhaust the specified maximum number of paths to consider. max-fields-for-field-sensitive Maximum number of fields in a structure treated in a field sensitive manner during pointer analysis. prefetch-latency Estimate on average number of instructions that are executed before prefetch finishes. The distance prefetched ahead is proportional to this constant. Increasing this number may also lead to less streams being prefetched (see simultaneous-prefetches). simultaneous-prefetches Maximum number of prefetches that can run at the same time. l1-cache-line-size The size of cache line in L1 data cache, in bytes. l1-cache-size The size of L1 data cache, in kilobytes. l2-cache-size The size of L2 data cache, in kilobytes. prefetch-dynamic-strides Whether the loop array prefetch pass should issue software prefetch hints for strides that are non-constant. In some cases this may be beneficial, though the fact the stride is non-constant may make it hard to predict when there is clear benefit to issuing these hints. Set to 1 if the prefetch hints should be issued for non-constant strides. Set to 0 if prefetch hints should be issued only for strides that are known to be constant and below prefetch-minimum-stride. prefetch-minimum-stride Minimum constant stride, in bytes, to start using prefetch hints for. If the stride is less than this threshold, prefetch hints will not be issued. This setting is useful for processors that have hardware prefetchers, in which case there may be conflicts between the hardware prefetchers and the software prefetchers. If the hardware prefetchers have a maximum stride they can handle, it should be used here to improve the use of software prefetchers. A value of -1 means we don't have a threshold and therefore prefetch hints can be issued for any constant stride. This setting is only useful for strides that are known and constant. destructive-interference-size constructive-interference-size The values for the C++17 variables \"std::hardwaredestructiveinterferencesize\" and \"std::hardwareconstructiveinterferencesize\". The destructive interference size is the minimum recommended offset between two independent concurrently-accessed objects; the constructive interference size is the maximum recommended size of contiguous memory accessed together. Typically both will be the size of an L1 cache line for the target, in bytes. For a generic target covering a range of L1 cache line sizes, typically the constructive interference size will be the small end of the range and the destructive size will be the large end. The destructive interference size is intended to be used for layout, and thus has ABI impact. The default value is not expected to be stable, and on some targets varies with -mtune, so use of this variable in a context where ABI stability is important, such as the public interface of a library, is strongly discouraged; if it is used in that context, users can stabilize the value using this option. The constructive interference size is less sensitive, as it is typically only used in a staticassert to make sure that a type fits within a cache line. See also -Winterference-size. loop-interchange-max-num-stmts The maximum number of stmts in a loop to be interchanged. loop-interchange-stride-ratio The minimum ratio between stride of two loops for interchange to be profitable. min-insn-to-prefetch-ratio The minimum ratio between the number of instructions and the number of prefetches to enable prefetching in a loop. prefetch-min-insn-to-mem-ratio The minimum ratio between the number of instructions and the number of memory references to enable prefetching in a loop. use-canonical-types Whether the compiler should use the \"canonical\" type system. Should always be 1, which uses a more efficient internal mechanism for comparing types in C++ and Objective-C++. However, if bugs in the canonical type system are causing compilation failures, set this value to 0 to disable canonical types. switch-conversion-max-branch-ratio Switch initialization conversion refuses to create arrays that are bigger than switch-conversion-max-branch-ratio times the number of branches in the switch. max-partial-antic-length Maximum length of the partial antic set computed during the tree partial redundancy elimination optimization (-ftree-pre) when optimizing at -O3 and above. For some sorts of source code the enhanced partial redundancy elimination optimization can run away, consuming all of the memory available on the host machine. This parameter sets a limit on the length of the sets that are computed, which prevents the runaway behavior. Setting a value of 0 for this parameter allows an unlimited set length. rpo-vn-max-loop-depth Maximum loop depth that is value-numbered optimistically. When the limit hits the innermost rpo-vn-max-loop-depth loops and the outermost loop in the loop nest are value-numbered optimistically and the remaining ones not. sccvn-max-alias-queries-per-access Maximum number of alias-oracle queries we perform when looking for redundancies for loads and stores. If this limit is hit the search is aborted and the load or store is not considered redundant. The number of queries is algorithmically limited to the number of stores on all paths from the load to the function entry. ira-max-loops-num IRA uses regional register allocation by default. If a function contains more loops than the number given by this parameter, only at most the given number of the most frequently-executed loops form regions for regional register allocation. ira-max-conflict-table-size Although IRA uses a sophisticated algorithm to compress the conflict table, the table can still require excessive amounts of memory for huge functions. If the conflict table for a function could be more than the size in MB given by this parameter, the register allocator instead uses a faster, simpler, and lower-quality algorithm that does not require building a pseudo-register conflict table. ira-loop-reserved-regs IRA can be used to evaluate more accurate register pressure in loops for decisions to move loop invariants (see -O3). The number of available registers reserved for some other purposes is given by this parameter. Default of the parameter is the best found from numerous experiments. ira-consider-dup-in-all-alts Make IRA to consider matching constraint (duplicated operand number) heavily in all available alternatives for preferred register class. If it is set as zero, it means IRA only respects the matching constraint when it's in the only available alternative with an appropriate register class. Otherwise, it means IRA will check all available alternatives for preferred register class even if it has found some choice with an appropriate register class and respect the found qualified matching constraint. ira-simple-lra-insn-threshold Approximate function insn number in 1K units triggering simple local RA. lra-inheritance-ebb-probability-cutoff LRA tries to reuse values reloaded in registers in subsequent insns. This optimization is called inheritance. EBB is used as a region to do this optimization. The parameter defines a minimal fall-through edge probability in percentage used to add BB to inheritance EBB in LRA. The default value was chosen from numerous runs of SPEC2000 on x86-64. loop-invariant-max-bbs-in-loop Loop invariant motion can be very expensive, both in compilation time and in amount of needed compile-time memory, with very large loops. Loops with more basic blocks than this parameter won't have loop invariant motion optimization performed on them. loop-max-datarefs-for-datadeps Building data dependencies is expensive for very large loops. This parameter limits the number of data references in loops that are considered for data dependence analysis. These large loops are no handled by the optimizations using loop data dependencies. max-vartrack-size Sets a maximum number of hash table slots to use during variable tracking dataflow analysis of any function. If this limit is exceeded with variable tracking at assignments enabled, analysis for that function is retried without it, after removing all debug insns from the function. If the limit is exceeded even without debug insns, var tracking analysis is completely disabled for the function. Setting the parameter to zero makes it unlimited. max-vartrack-expr-depth Sets a maximum number of recursion levels when attempting to map variable names or debug temporaries to value expressions. This trades compilation time for more complete debug information. If this is set too low, value expressions that are available and could be represented in debug information may end up not being used; setting this higher may enable the compiler to find more complex debug expressions, but compile time and memory use may grow. max-debug-marker-count Sets a threshold on the number of debug markers (e.g. begin stmt markers) to avoid complexity explosion at inlining or expanding to RTL. If a function has more such gimple stmts than the set limit, such stmts will be dropped from the inlined copy of a function, and from its RTL expansion. min-nondebug-insn-uid Use uids starting at this parameter for nondebug insns. The range below the parameter is reserved exclusively for debug insns created by -fvar-tracking-assignments, but debug insns may get (non-overlapping) uids above it if the reserved range is exhausted. ipa-sra-deref-prob-threshold IPA-SRA replaces a pointer which is known not be NULL with one or more new parameters only when the probability (in percent, relative to function entry) of it being dereferenced is higher than this parameter. ipa-sra-ptr-growth-factor IPA-SRA replaces a pointer to an aggregate with one or more new parameters only when their cumulative size is less or equal to ipa-sra-ptr-growth-factor times the size of the original pointer parameter. ipa-sra-ptrwrap-growth-factor Additional maximum allowed growth of total size of new parameters that ipa-sra replaces a pointer to an aggregate with, if it points to a local variable that the caller only writes to and passes it as an argument to other functions. ipa-sra-max-replacements Maximum pieces of an aggregate that IPA-SRA tracks. As a consequence, it is also the maximum number of replacements of a formal parameter. sra-max-scalarization-size-Ospeed sra-max-scalarization-size-Osize The two Scalar Reduction of Aggregates passes (SRA and IPA-SRA) aim to replace scalar parts of aggregates with uses of independent scalar variables. These parameters control the maximum size, in storage units, of aggregate which is considered for replacement when compiling for speed (sra-max-scalarization-size-Ospeed) or size (sra-max-scalarization-size-Osize) respectively. sra-max-propagations The maximum number of artificial accesses that Scalar Replacement of Aggregates (SRA) will track, per one local variable, in order to facilitate copy propagation. tm-max-aggregate-size When making copies of thread-local variables in a transaction, this parameter specifies the size in bytes after which variables are saved with the logging functions as opposed to save/restore code sequence pairs. This option only applies when using -fgnu-tm. graphite-max-nb-scop-params To avoid exponential effects in the Graphite loop transforms, the number of parameters in a Static Control Part (SCoP) is bounded. A value of zero can be used to lift the bound. A variable whose value is unknown at compilation time and defined outside a SCoP is a parameter of the SCoP. loop-block-tile-size Loop blocking or strip mining transforms, enabled with -floop-block or -floop-strip-mine, strip mine each loop in the loop nest by a given number of iterations. The strip length can be changed using the loop-block-tile-size parameter. ipa-jump-function-lookups Specifies number of statements visited during jump function offset discovery. ipa-cp-value-list-size IPA-CP attempts to track all possible values and types passed to a function's parameter in order to propagate them and perform devirtualization. ipa-cp-value- list-size is the maximum number of values and types it stores per one formal parameter of a function. ipa-cp-eval-threshold IPA-CP calculates its own score of cloning profitability heuristics and performs those cloning opportunities with scores that exceed ipa-cp-eval-threshold. ipa-cp-max-recursive-depth Maximum depth of recursive cloning for self-recursive function. ipa-cp-min-recursive-probability Recursive cloning only when the probability of call being executed exceeds the parameter. ipa-cp-profile-count-base When using -fprofile-use option, IPA-CP will consider the measured execution count of a call graph edge at this percentage position in their histogram as the basis for its heuristics calculation. ipa-cp-recursive-freq-factor The number of times interprocedural copy propagation expects recursive functions to call themselves. ipa-cp-recursion-penalty Percentage penalty the recursive functions will receive when they are evaluated for cloning. ipa-cp-single-call-penalty Percentage penalty functions containing a single call to another function will receive when they are evaluated for cloning. ipa-max-agg-items IPA-CP is also capable to propagate a number of scalar values passed in an aggregate. ipa-max-agg-items controls the maximum number of such values per one parameter. ipa-cp-loop-hint-bonus When IPA-CP determines that a cloning candidate would make the number of iterations of a loop known, it adds a bonus of ipa-cp-loop-hint-bonus to the profitability score of the candidate. ipa-max-loop-predicates The maximum number of different predicates IPA will use to describe when loops in a function have known properties. ipa-max-aa-steps During its analysis of function bodies, IPA-CP employs alias analysis in order to track values pointed to by function parameters. In order not spend too much time analyzing huge functions, it gives up and consider all memory clobbered after examining ipa-max-aa-steps statements modifying memory. ipa-max-switch-predicate-bounds Maximal number of boundary endpoints of case ranges of switch statement. For switch exceeding this limit, IPA-CP will not construct cloning cost predicate, which is used to estimate cloning benefit, for default case of the switch statement. ipa-max-param-expr-ops IPA-CP will analyze conditional statement that references some function parameter to estimate benefit for cloning upon certain constant value. But if number of operations in a parameter expression exceeds ipa-max-param-expr-ops, the expression is treated as complicated one, and is not handled by IPA analysis. lto-partitions Specify desired number of partitions produced during WHOPR compilation. The number of partitions should exceed the number of CPUs used for compilation. lto-min-partition Size of minimal partition for WHOPR (in estimated instructions). This prevents expenses of splitting very small programs into too many partitions. lto-max-partition Size of max partition for WHOPR (in estimated instructions). to provide an upper bound for individual size of partition. Meant to be used only with balanced partitioning. lto-max-streaming-parallelism Maximal number of parallel processes used for LTO streaming. cxx-max-namespaces-for-diagnostic-help The maximum number of namespaces to consult for suggestions when C++ name lookup fails for an identifier. sink-frequency-threshold The maximum relative execution frequency (in percents) of the target block relative to a statement's original block to allow statement sinking of a statement. Larger numbers result in more aggressive statement sinking. A small positive adjustment is applied for statements with memory operands as those are even more profitable so sink. max-stores-to-sink The maximum number of conditional store pairs that can be sunk. Set to 0 if either vectorization (-ftree-vectorize) or if-conversion (-ftree-loop-if-convert) is disabled. case-values-threshold The smallest number of different values for which it is best to use a jump-table instead of a tree of conditional branches. If the value is 0, use the default for the machine. jump-table-max-growth-ratio-for-size The maximum code size growth ratio when expanding into a jump table (in percent). The parameter is used when optimizing for size. jump-table-max-growth-ratio-for-speed The maximum code size growth ratio when expanding into a jump table (in percent). The parameter is used when optimizing for speed. tree-reassoc-width Set the maximum number of instructions executed in parallel in reassociated tree. This parameter overrides target dependent heuristics used by default if has non zero value. sched-pressure-algorithm Choose between the two available implementations of -fsched-pressure. Algorithm 1 is the original implementation and is the more likely to prevent instructions from being reordered. Algorithm 2 was designed to be a compromise between the relatively conservative approach taken by algorithm 1 and the rather aggressive approach taken by the default scheduler. It relies more heavily on having a regular register file and accurate register pressure classes. See haifa-sched.cc in the GCC sources for more details. The default choice depends on the target. max-slsr-cand-scan Set the maximum number of existing candidates that are considered when seeking a basis for a new straight-line strength reduction candidate. asan-globals Enable buffer overflow detection for global objects. This kind of protection is enabled by default if you are using -fsanitize=address option. To disable global objects protection use --param asan-globals=0. asan-stack Enable buffer overflow detection for stack objects. This kind of protection is enabled by default when using -fsanitize=address. To disable stack protection use --param asan-stack=0 option. asan-instrument-reads Enable buffer overflow detection for memory reads. This kind of protection is enabled by default when using -fsanitize=address. To disable memory reads protection use --param asan-instrument-reads=0. asan-instrument-writes Enable buffer overflow detection for memory writes. This kind of protection is enabled by default when using -fsanitize=address. To disable memory writes protection use --param asan-instrument-writes=0 option. asan-memintrin Enable detection for built-in functions. This kind of protection is enabled by default when using -fsanitize=address. To disable built-in functions protection use --param asan-memintrin=0. asan-use-after-return Enable detection of use-after-return. This kind of protection is enabled by default when using the -fsanitize=address option. To disable it use --param asan-use-after-return=0. Note: By default the check is disabled at run time. To enable it, add \"detectstackuseafterreturn=1\" to the environment variable ASANOPTIONS. asan-instrumentation-with-call-threshold If number of memory accesses in function being instrumented is greater or equal to this number, use callbacks instead of inline checks. E.g. to disable inline code use --param asan-instrumentation-with-call-threshold=0. asan-kernel-mem-intrinsic-prefix If nonzero, prefix calls to \"memcpy\", \"memset\" and \"memmove\" with asan or hwasan for -fsanitize=kernel-address or -fsanitize=kernel-hwaddress, respectively. hwasan-instrument-stack Enable hwasan instrumentation of statically sized stack-allocated variables. This kind of instrumentation is enabled by default when using -fsanitize=hwaddress and disabled by default when using -fsanitize=kernel-hwaddress. To disable stack instrumentation use --param hwasan-instrument-stack=0, and to enable it use --param hwasan-instrument-stack=1. hwasan-random-frame-tag When using stack instrumentation, decide tags for stack variables using a deterministic sequence beginning at a random tag for each frame. With this parameter unset tags are chosen using the same sequence but beginning from 1. This is enabled by default for -fsanitize=hwaddress and unavailable for -fsanitize=kernel-hwaddress. To disable it use --param hwasan-random-frame-tag=0. hwasan-instrument-allocas Enable hwasan instrumentation of dynamically sized stack-allocated variables. This kind of instrumentation is enabled by default when using -fsanitize=hwaddress and disabled by default when using -fsanitize=kernel-hwaddress. To disable instrumentation of such variables use --param hwasan-instrument-allocas=0, and to enable it use --param hwasan-instrument-allocas=1. hwasan-instrument-reads Enable hwasan checks on memory reads. Instrumentation of reads is enabled by default for both -fsanitize=hwaddress and -fsanitize=kernel-hwaddress. To disable checking memory reads use --param hwasan-instrument-reads=0. hwasan-instrument-writes Enable hwasan checks on memory writes. Instrumentation of writes is enabled by default for both -fsanitize=hwaddress and -fsanitize=kernel-hwaddress. To disable checking memory writes use --param hwasan-instrument-writes=0. hwasan-instrument-mem-intrinsics Enable hwasan instrumentation of builtin functions. Instrumentation of these builtin functions is enabled by default for both -fsanitize=hwaddress and -fsanitize=kernel-hwaddress. To disable instrumentation of builtin functions use --param hwasan-instrument-mem-intrinsics=0. use-after-scope-direct-emission-threshold If the size of a local variable in bytes is smaller or equal to this number, directly poison (or unpoison) shadow memory instead of using run-time callbacks. tsan-distinguish-volatile Emit special instrumentation for accesses to volatiles. tsan-instrument-func-entry-exit Emit instrumentation calls to tsanfuncentry() and tsanfuncexit(). max-fsm-thread-path-insns Maximum number of instructions to copy when duplicating blocks on a finite state automaton jump thread path. threader-debug threader-debug=[none|all] Enables verbose dumping of the threader solver. parloops-chunk-size Chunk size of omp schedule for loops parallelized by parloops. parloops-schedule Schedule type of omp schedule for loops parallelized by parloops (static, dynamic, guided, auto, runtime). parloops-min-per-thread The minimum number of iterations per thread of an innermost parallelized loop for which the parallelized variant is preferred over the single threaded one. Note that for a parallelized loop nest the minimum number of iterations of the outermost loop per thread is two. max-ssa-name-query-depth Maximum depth of recursion when querying properties of SSA names in things like fold routines. One level of recursion corresponds to following a use-def chain. max-speculative-devirt-maydefs The maximum number of may-defs we analyze when looking for a must-def specifying the dynamic type of an object that invokes a virtual call we may be able to devirtualize speculatively. evrp-sparse-threshold Maximum number of basic blocks before EVRP uses a sparse cache. ranger-debug Specifies the type of debug output to be issued for ranges. evrp-switch-limit Specifies the maximum number of switch cases before EVRP ignores a switch. unroll-jam-min-percent The minimum percentage of memory references that must be optimized away for the unroll-and-jam transformation to be considered profitable. unroll-jam-max-unroll The maximum number of times the outer loop should be unrolled by the unroll-and-jam transformation. max-rtl-if-conversion-unpredictable-cost Maximum permissible cost for the sequence that would be generated by the RTL if- conversion pass for a branch that is considered unpredictable. max-variable-expansions-in-unroller If -fvariable-expansion-in-unroller is used, the maximum number of times that an individual variable will be expanded during loop unrolling. partial-inlining-entry-probability Maximum probability of the entry BB of split region (in percent relative to entry BB of the function) to make partial inlining happen. max-tracked-strlens Maximum number of strings for which strlen optimization pass will track string lengths. gcse-after-reload-partial-fraction The threshold ratio for performing partial redundancy elimination after reload. gcse-after-reload-critical-fraction The threshold ratio of critical edges execution count that permit performing redundancy elimination after reload. max-loop-header-insns The maximum number of insns in loop header duplicated by the copy loop headers pass. vect-epilogues-nomask Enable loop epilogue vectorization using smaller vector size. vect-partial-vector-usage Controls when the loop vectorizer considers using partial vector loads and stores as an alternative to falling back to scalar code. 0 stops the vectorizer from ever using partial vector loads and stores. 1 allows partial vector loads and stores if vectorization removes the need for the code to iterate. 2 allows partial vector loads and stores in all loops. The parameter only has an effect on targets that support partial vector loads and stores. vect-inner-loop-cost-factor The maximum factor which the loop vectorizer applies to the cost of statements in an inner loop relative to the loop being vectorized. The factor applied is the maximum of the estimated number of iterations of the inner loop and this parameter. The default value of this parameter is 50. vect-induction-float Enable loop vectorization of floating point inductions. avoid-fma-max-bits Maximum number of bits for which we avoid creating FMAs. sms-loop-average-count-threshold A threshold on the average loop count considered by the swing modulo scheduler. sms-dfa-history The number of cycles the swing modulo scheduler considers when checking conflicts using DFA. graphite-allow-codegen-errors Whether codegen errors should be ICEs when -fchecking. sms-max-ii-factor A factor for tuning the upper bound that swing modulo scheduler uses for scheduling a loop. lra-max-considered-reload-pseudos The max number of reload pseudos which are considered during spilling a non-reload pseudo. max-pow-sqrt-depth Maximum depth of sqrt chains to use when synthesizing exponentiation by a real constant. max-dse-active-local-stores Maximum number of active local stores in RTL dead store elimination. asan-instrument-allocas Enable asan allocas/VLAs protection. max-iterations-computation-cost Bound on the cost of an expression to compute the number of iterations. max-isl-operations Maximum number of isl operations, 0 means unlimited. graphite-max-arrays-per-scop Maximum number of arrays per scop. max-vartrack-reverse-op-size Max. size of loc list for which reverse ops should be added. fsm-scale-path-stmts Scale factor to apply to the number of statements in a threading path crossing a loop backedge when comparing to --param=max-jump-thread-duplication-stmts. uninit-control-dep-attempts Maximum number of nested calls to search for control dependencies during uninitialized variable analysis. uninit-max-chain-len Maximum number of predicates anded for each predicate ored in the normalized predicate chain. uninit-max-num-chains Maximum number of predicates ored in the normalized predicate chain. sched-autopref-queue-depth Hardware autoprefetcher scheduler model control flag. Number of lookahead cycles the model looks into; at ' ' only enable instruction sorting heuristic. loop-versioning-max-inner-insns The maximum number of instructions that an inner loop can have before the loop versioning pass considers it too big to copy. loop-versioning-max-outer-insns The maximum number of instructions that an outer loop can have before the loop versioning pass considers it too big to copy, discounting any instructions in inner loops that directly benefit from versioning. ssa-name-def-chain-limit The maximum number of SSANAME assignments to follow in determining a property of a variable such as its value. This limits the number of iterations or recursive calls GCC performs when optimizing certain statements or when determining their validity prior to issuing diagnostics. store-merging-max-size Maximum size of a single store merging region in bytes. hash-table-verification-limit The number of elements for which hash table verification is done for each searched element. max-find-base-term-values Maximum number of VALUEs handled during a single findbaseterm call. analyzer-max-enodes-per-program-point The maximum number of exploded nodes per program point within the analyzer, before terminating analysis of that point. analyzer-max-constraints The maximum number of constraints per state. analyzer-min-snodes-for-call-summary The minimum number of supernodes within a function for the analyzer to consider summarizing its effects at call sites. analyzer-max-enodes-for-full-dump The maximum depth of exploded nodes that should appear in a dot dump before switching to a less verbose format. analyzer-max-recursion-depth The maximum number of times a callsite can appear in a call stack within the analyzer, before terminating analysis of a call that would recurse deeper. analyzer-max-svalue-depth The maximum depth of a symbolic value, before approximating the value as unknown. analyzer-max-infeasible-edges The maximum number of infeasible edges to reject before declaring a diagnostic as infeasible. gimple-fe-computed-hot-bb-threshold The number of executions of a basic block which is considered hot. The parameter is used only in GIMPLE FE. analyzer-bb-explosion-factor The maximum number of 'after supernode' exploded nodes within the analyzer per supernode, before terminating analysis. ranger-logical-depth Maximum depth of logical expression evaluation ranger will look through when evaluating outgoing edge ranges. ranger-recompute-depth Maximum depth of instruction chains to consider for recomputation in the outgoing range calculator. relation-block-limit Maximum number of relations the oracle will register in a basic block. min-pagesize Minimum page size for warning purposes. openacc-kernels Specify mode of OpenACC `kernels' constructs handling. With --param=openacc-kernels=decompose, OpenACC `kernels' constructs are decomposed into parts, a sequence of compute constructs, each then handled individually. This is work in progress. With --param=openacc-kernels=parloops, OpenACC `kernels' constructs are handled by the parloops pass, en bloc. This is the current default. openacc-privatization Control whether the -fopt-info-omp-note and applicable -fdump-tree-*-details options emit OpenACC privatization diagnostics. With --param=openacc-privatization=quiet, don't diagnose. This is the current default. With --param=openacc-privatization=noisy, do diagnose. The following choices of name are available on AArch64 targets: aarch64-sve-compare-costs When vectorizing for SVE, consider using \"unpacked\" vectors for smaller elements and use the cost model to pick the cheapest approach. Also use the cost model to choose between SVE and Advanced SIMD vectorization. Using unpacked vectors includes storing smaller elements in larger containers and accessing elements with extending loads and truncating stores. aarch64-float-recp-precision The number of Newton iterations for calculating the reciprocal for float type. The precision of division is proportional to this param when division approximation is enabled. The default value is 1. aarch64-double-recp-precision The number of Newton iterations for calculating the reciprocal for double type. The precision of division is propotional to this param when division approximation is enabled. The default value is 2. aarch64-autovec-preference Force an ISA selection strategy for auto-vectorization. Accepts values from 0 to 4, inclusive. 0 Use the default heuristics. 1 Use only Advanced SIMD for auto-vectorization. 2 Use only SVE for auto-vectorization. 3 Use both Advanced SIMD and SVE. Prefer Advanced SIMD when the costs are deemed equal. 4 Use both Advanced SIMD and SVE. Prefer SVE when the costs are deemed equal. The default value is 0. aarch64-loop-vect-issue-rate-niters The tuning for some AArch64 CPUs tries to take both latencies and issue rates into account when deciding whether a loop should be vectorized using SVE, vectorized using Advanced SIMD, or not vectorized at all. If this parameter is set to n, GCC will not use this heuristic for loops that are known to execute in fewer than n Advanced SIMD iterations. aarch64-vect-unroll-limit The vectorizer will use available tuning information to determine whether it would be beneficial to unroll the main vectorized loop and by how much. This parameter set's the upper bound of how much the vectorizer will unroll the main loop. The default value is four. The following choices of name are available on i386 and x8664 targets: x86-stlf-window-ninsns Instructions number above which STFL stall penalty can be compensated. x86-stv-max-visits The maximum number of use and def visits when discovering a STV chain before the discovery is aborted."
        },
        {
            "flag": "-p",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "(for -p) or gprof (for -pg). You must use this option when compiling the source files you want data about, and you must also use it when linking. You can use the function attribute \"noinstrumentfunction\" to suppress profiling of individual functions when compiling with these options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Add code so that program flow arcs are instrumented. During execution the program records how many times each branch and call is executed and how many times it is taken or returns. On targets that support constructors with priority support, profiling properly handles constructors, destructors and C++ constructors (and destructors) of classes which are used as a type of a global variable. When the compiled program exits it saves this data to a file called auxname.gcda for each source file. The data may be used for profile-directed optimizations (-fbranch-probabilities), or for test coverage analysis (-ftest-coverage). Each object file's auxname is generated from the name of the output file, if explicitly specified and it is not the final executable, otherwise it is the basename of the source file. In both cases any suffix is removed (e.g. foo.gcda for input file dir/foo.c, or dir/foo.gcda for output file specified as -o dir/foo.o). Note that if a command line directly links source files, the corresponding .gcda files will be prefixed with the unsuffixed name of the output file. E.g. \"gcc a.c b.c -o binary\" would generate binary-a.gcda and binary-b.gcda files."
        },
        {
            "flag": "",
            "long": "--coverage",
            "arg": null,
            "description": "This option is used to compile and link code instrumented for coverage analysis. The option is a synonym for -fprofile-arcs -ftest-coverage (when compiling) and -lgcov (when linking). See the documentation for those options for more details. * Compile the source files with -fprofile-arcs plus optimization and code generation options. For test coverage analysis, use the additional -ftest-coverage option. You do not need to profile every source file in a program. * Compile the source files additionally with -fprofile-abs-path to create absolute path names in the .gcno files. This allows gcov to find the correct sources in projects where compilations occur with different working directories. * Link your object files with -lgcov or -fprofile-arcs (the latter implies the former). * Run the program on a representative workload to generate the arc profile information. This may be repeated any number of times. You can run concurrent instances of your program, and provided that the file system supports locking, the data files will be correctly updated. Unless a strict ISO C dialect option is in effect, \"fork\" calls are detected and correctly handled without double counting. Moreover, an object file can be recompiled multiple times and the corresponding .gcda file merges as long as the source file and the compiler options are unchanged. * For profile-directed optimizations, compile the source files again with the same optimization and code generation options plus -fbranch-probabilities. * For test coverage analysis, use gcov to produce human readable information from the .gcno and .gcda files. Refer to the gcov documentation for further information. With -fprofile-arcs, for each function of your program GCC creates a program flow graph, then finds a spanning tree for the graph. Only arcs that are not on the spanning tree have to be instrumented: the compiler adds code to count the number of times that these arcs are executed. When an arc is the only exit or only entrance to a block, the instrumentation code can be added to the block; otherwise, a new basic block must be created to hold the instrumentation code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Produce a notes file that the gcov code-coverage utility can use to show program coverage. Each source file's note file is called auxname.gcno. Refer to the -fprofile-arcs option above for a description of auxname and instructions on how to generate test coverage data. Coverage data matches the source files more closely if you do not optimize."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Automatically convert relative source file names to absolute path names in the .gcno files. This allows gcov to find the correct sources in projects where compilations occur with different working directories."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the directory to search for the profile data files in to path. This option affects only the profile data generated by -fprofile-generate, -ftest-coverage, -fprofile-arcs and used by -fprofile-use and -fbranch-probabilities and its related options. Both absolute and relative paths can be used. By default, GCC uses the current directory as path, thus the profile data file appears in the same directory as the object file. In order to prevent the file name clashing, if the object file name is not an absolute path, we mangle the absolute path of the sourcename.gcda file and use it as the file name of a .gcda file. See details about the file naming in -fprofile-arcs. See similar option -fprofile-note. When an executable is run in a massive parallel environment, it is recommended to save profile to different folders. That can be done with variables in path that are exported during run-time: %p process ID. %q{VAR} value of environment variable VAR"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable options usually used for instrumenting application to produce profile useful for later recompilation with profile feedback based optimization. You must use -fprofile-generate both when compiling and when linking your program. The following options are enabled: -fprofile-arcs, -fprofile-values, -finline-functions, and -fipa-bit-cp. If path is specified, GCC looks at the path to find the profile feedback data files. See -fprofile-dir. To optimize the program based on the collected profile information, use -fprofile-use."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Register the profile information in the specified section instead of using a constructor/destructor. The section name is name if it is specified, otherwise the section name defaults to \".gcovinfo\". A pointer to the profile information generated by -fprofile-arcs is placed in the specified section for each translation unit. This option disables the profile information registration through a constructor and it disables the profile information processing through a destructor. This option is not intended to be used in hosted environments such as GNU/Linux. It targets freestanding environments (for example embedded systems) with limited resources which do not support constructors/destructors or the C library file I/O. The linker could collect the input sections in a continuous memory block and define start and end symbols. A GNU linker script example which defines a linker output section follows: .gcovinfo : { PROVIDE (gcovinfostart = .); KEEP (*(.gcovinfo)) PROVIDE (gcovinfoend = .); } The program could dump the profiling information registered in this linker set for example like this: #include <gcov.h> #include <stdio.h> #include <stdlib.h> extern const struct gcovinfo *const gcovinfostart[]; extern const struct gcovinfo *const gcovinfoend[]; static void dump (const void *d, unsigned n, void *arg) { const unsigned char *c = d; for (unsigned i = 0; i < n; ++i) printf (\"%02x\", c[i]); } static void filename (const char *f, void *arg) { gcovfilenametogcfn (f, dump, arg ); } static void * allocate (unsigned length, void *arg) { return malloc (length); } static void dumpgcovinfo (void) { const struct gcovinfo *const *info = gcovinfostart; const struct gcovinfo *const *end = gcovinfoend; /* Obfuscate variable to prevent compiler optimizations. */ asm (\"\" : \"+r\" (info)); while (info != end) { void *arg = NULL; gcovinfotogcda (*info, filename, dump, allocate, arg); putchar ('\\n'); ++info; } } int main (void) { dumpgcovinfo (); return 0; } The merge-stream subcommand of gcov-tool may be used to deserialize the data stream generated by the \"gcovfilenametogcfn\" and \"gcovinfotogcda\" functions and merge the profile information into .gcda files on the host filesystem."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If path is specified, GCC saves .gcno file into path location. If you combine the option with multiple source files, the .gcno file will be overwritten."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option can be used in combination with profile-generate=profiledir and profile-use=profiledir to inform GCC where is the base directory of built source tree. By default profiledir will contain files with mangled absolute paths of all object files in the built project. This is not desirable when directory used to build the instrumented binary differs from the directory used to build the binary optimized with profile feedback because the profile data will not be found during the optimized build. In such setups -fprofile-prefix-path=path with path pointing to the base directory of the build can be used to strip the irrelevant part of the path and keep all file names relative to the main build directory."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When compiling files residing in directory old, record profiling information (with --coverage) describing them as if the files resided in directory new instead. See also -ffile-prefix-map and -fcanon-prefix-map."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Alter the update method for an application instrumented for profile feedback based optimization. The method argument should be one of single, atomic or prefer-atomic. The first one is useful for single-threaded applications, while the second one prevents profile corruption by emitting thread-safe code. Warning: When an application does not properly join all threads (or creates an detached thread), a profile file can be still corrupted. Using prefer-atomic would be transformed either to atomic, when supported by a target, or to single otherwise. The GCC driver automatically selects prefer-atomic when -pthread is present in the command line."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Instrument only functions from files whose name matches any of the regular expressions (separated by semi-colons). For example, -fprofile-filter-files=main\\.c;module.*\\.c will instrument only main.c and all C files starting with 'module'."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Instrument only functions from files whose name does not match any of the regular expressions (separated by semi-colons). For example, -fprofile-exclude-files=/usr/.* will prevent instrumentation of all files that are located in the /usr/ folder."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Control level of reproducibility of profile gathered by \"-fprofile-generate\". This makes it possible to rebuild program with same outcome which is useful, for example, for distribution packages. With -fprofile-reproducible=serial the profile gathered by -fprofile-generate is reproducible provided the trained program behaves the same at each invocation of the train run, it is not multi-threaded and profile data streaming is always done in the same order. Note that profile streaming happens at the end of program run but also before \"fork\" function is invoked. Note that it is quite common that execution counts of some part of programs depends, for example, on length of temporary file names or memory space randomization (that may affect hash-table collision rate). Such non-reproducible part of programs may be annotated by \"noinstrumentfunction\" function attribute. gcov-dump with -l can be used to dump gathered data and verify that they are indeed reproducible. With -fprofile-reproducible=parallel-runs collected profile stays reproducible regardless the order of streaming of the data into gcda files. This setting makes it possible to run multiple instances of instrumented program in parallel (such as with \"make -j\"). This reduces quality of gathered data, in particular of indirect call profiling."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable AddressSanitizer, a fast memory error detector. Memory access instructions are instrumented to detect out-of-bounds and use-after-free bugs. The option enables -fsanitize-address-use-after-scope. See <https://github.com/google/sanitizers/wiki/AddressSanitizer> for more details. The run- time behavior can be influenced using the ASANOPTIONS environment variable. When set to \"help=1\", the available options are shown at startup of the instrumented program. See <https://github.com/google/sanitizers/wiki/AddressSanitizerFlags#run-time-flags> for a list of supported options. The option cannot be combined with -fsanitize=thread or -fsanitize=hwaddress. Note that the only target -fsanitize=hwaddress is currently supported on is AArch64. To get more accurate stack traces, it is possible to use options such as -O0, -O1, or -Og (which, for instance, prevent most function inlining), -fno-optimize-sibling-calls (which prevents optimizing sibling and tail recursive calls; this option is implicit for -O0, -O1, or -Og), or -fno-ipa-icf (which disables Identical Code Folding for functions). Since multiple runs of the program may yield backtraces with different addresses due to ASLR (Address Space Layout Randomization), it may be desirable to turn ASLR off. On Linux, this can be achieved with setarch `uname -m` -R ./prog."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable AddressSanitizer for Linux kernel. See <https://github.com/google/kernel-sanitizers> for more details."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable Hardware-assisted AddressSanitizer, which uses a hardware ability to ignore the top byte of a pointer to allow the detection of memory errors with a low memory overhead. Memory access instructions are instrumented to detect out-of-bounds and use-after-free bugs. The option enables -fsanitize-address-use-after-scope. See <https://clang.llvm.org/docs/HardwareAssistedAddressSanitizerDesign.html> for more details. The run-time behavior can be influenced using the HWASANOPTIONS environment variable. When set to \"help=1\", the available options are shown at startup of the instrumented program. The option cannot be combined with -fsanitize=thread or -fsanitize=address, and is currently only available on AArch64."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable Hardware-assisted AddressSanitizer for compilation of the Linux kernel. Similar to -fsanitize=kernel-address but using an alternate instrumentation method, and similar to -fsanitize=hwaddress but with instrumentation differences necessary for compiling the Linux kernel. These differences are to avoid hwasan library initialization calls and to account for the stack pointer having a different value in its top byte. Note: This option has different defaults to the -fsanitize=hwaddress. Instrumenting the stack and alloca calls are not on by default but are still possible by specifying the command-line options --param hwasan-instrument-stack=1 and --param hwasan-instrument-allocas=1 respectively. Using a random frame tag is not implemented for kernel instrumentation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Instrument comparison operation (<, <=, >, >=) with pointer operands. The option must be combined with either -fsanitize=kernel-address or -fsanitize=address The option cannot be combined with -fsanitize=thread. Note: By default the check is disabled at run time. To enable it, add \"detectinvalidpointerpairs=2\" to the environment variable ASANOPTIONS. Using \"detectinvalidpointerpairs=1\" detects invalid operation only when both pointers are non-null."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Instrument subtraction with pointer operands. The option must be combined with either -fsanitize=kernel-address or -fsanitize=address The option cannot be combined with -fsanitize=thread. Note: By default the check is disabled at run time. To enable it, add \"detectinvalidpointerpairs=2\" to the environment variable ASANOPTIONS. Using \"detectinvalidpointerpairs=1\" detects invalid operation only when both pointers are non-null."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable ShadowCallStack, a security enhancement mechanism used to protect programs against return address overwrites (e.g. stack buffer overflows.) It works by saving a function's return address to a separately allocated shadow call stack in the function prologue and restoring the return address from the shadow call stack in the function epilogue. Instrumentation only occurs in functions that need to save the return address to the stack. Currently it only supports the aarch64 platform. It is specifically designed for linux kernels that enable the CONFIGSHADOWCALLSTACK option. For the user space programs, runtime support is not currently provided in libc and libgcc. Users who want to use this feature in user space need to provide their own support for the runtime. It should be noted that this may cause the ABI rules to be broken. On aarch64, the instrumentation makes use of the platform register \"x18\". This generally means that any code that may run on the same thread as code compiled with ShadowCallStack must be compiled with the flag -ffixed-x18, otherwise functions compiled without -ffixed-x18 might clobber \"x18\" and so corrupt the shadow stack pointer. Also, because there is no userspace runtime support, code compiled with ShadowCallStack cannot use exception handling. Use -fno-exceptions to turn off exceptions. See <https://clang.llvm.org/docs/ShadowCallStack.html> for more details."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable ThreadSanitizer, a fast data race detector. Memory access instructions are instrumented to detect data race bugs. See <https://github.com/google/sanitizers/wiki#threadsanitizer> for more details. The run- time behavior can be influenced using the TSANOPTIONS environment variable; see <https://github.com/google/sanitizers/wiki/ThreadSanitizerFlags> for a list of supported options. The option cannot be combined with -fsanitize=address, -fsanitize=leak. Note that sanitized atomic builtins cannot throw exceptions when operating on invalid memory addresses with non-call exceptions (-fnon-call-exceptions)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable LeakSanitizer, a memory leak detector. This option only matters for linking of executables. The executable is linked against a library that overrides \"malloc\" and other allocator functions. See <https://github.com/google/sanitizers/wiki/AddressSanitizerLeakSanitizer> for more details. The run-time behavior can be influenced using the LSANOPTIONS environment variable. The option cannot be combined with -fsanitize=thread."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable UndefinedBehaviorSanitizer, a fast undefined behavior detector. Various computations are instrumented to detect undefined behavior at runtime. See <https://clang.llvm.org/docs/UndefinedBehaviorSanitizer.html> for more details. The run-time behavior can be influenced using the UBSANOPTIONS environment variable. Current suboptions are: -fsanitize=shift This option enables checking that the result of a shift operation is not undefined. Note that what exactly is considered undefined differs slightly between C and C++, as well as between ISO C90 and C99, etc. This option has two suboptions, -fsanitize=shift-base and -fsanitize=shift-exponent. -fsanitize=shift-exponent This option enables checking that the second argument of a shift operation is not negative and is smaller than the precision of the promoted first argument. -fsanitize=shift-base If the second argument of a shift operation is within range, check that the result of a shift operation is not undefined. Note that what exactly is considered undefined differs slightly between C and C++, as well as between ISO C90 and C99, etc. -fsanitize=integer-divide-by-zero Detect integer division by zero. -fsanitize=unreachable With this option, the compiler turns the \"builtinunreachable\" call into a diagnostics message call instead. When reaching the \"builtinunreachable\" call, the behavior is undefined. -fsanitize=vla-bound This option instructs the compiler to check that the size of a variable length array is positive. -fsanitize=null This option enables pointer checking. Particularly, the application built with this option turned on will issue an error message when it tries to dereference a NULL pointer, or if a reference (possibly an rvalue reference) is bound to a NULL pointer, or if a method is invoked on an object pointed by a NULL pointer. -fsanitize=return This option enables return statement checking. Programs built with this option turned on will issue an error message when the end of a non-void function is reached without actually returning a value. This option works in C++ only. -fsanitize=signed-integer-overflow This option enables signed integer overflow checking. We check that the result of \"+\", \"*\", and both unary and binary \"-\" does not overflow in the signed arithmetics. This also detects \"INTMIN / -1\" signed division. Note, integer promotion rules must be taken into account. That is, the following is not an overflow: signed char a = SCHARMAX; a++; -fsanitize=bounds This option enables instrumentation of array bounds. Various out of bounds accesses are detected. Flexible array members, flexible array member-like arrays, and initializers of variables with static storage are not instrumented, with the exception of flexible array member-like arrays for which \"-fstrict-flex-arrays\" or \"-fstrict-flex-arrays=\" options or \"strictflexarray\" attributes say they shouldn't be treated like flexible array member-like arrays. -fsanitize=bounds-strict This option enables strict instrumentation of array bounds. Most out of bounds accesses are detected, including flexible array member-like arrays. Initializers of variables with static storage are not instrumented. -fsanitize=alignment This option enables checking of alignment of pointers when they are dereferenced, or when a reference is bound to insufficiently aligned target, or when a method or constructor is invoked on insufficiently aligned object. -fsanitize=object-size This option enables instrumentation of memory references using the \"builtindynamicobjectsize\" function. Various out of bounds pointer accesses are detected. -fsanitize=float-divide-by-zero Detect floating-point division by zero. Unlike other similar options, -fsanitize=float-divide-by-zero is not enabled by -fsanitize=undefined, since floating-point division by zero can be a legitimate way of obtaining infinities and NaNs. -fsanitize=float-cast-overflow This option enables floating-point type to integer conversion checking. We check that the result of the conversion does not overflow. Unlike other similar options, -fsanitize=float-cast-overflow is not enabled by -fsanitize=undefined. This option does not work well with \"FEINVALID\" exceptions enabled. -fsanitize=nonnull-attribute This option enables instrumentation of calls, checking whether null values are not passed to arguments marked as requiring a non-null value by the \"nonnull\" function attribute. -fsanitize=returns-nonnull-attribute This option enables instrumentation of return statements in functions marked with \"returnsnonnull\" function attribute, to detect returning of null values from such functions. -fsanitize=bool This option enables instrumentation of loads from bool. If a value other than 0/1 is loaded, a run-time error is issued. -fsanitize=enum This option enables instrumentation of loads from an enum type. If a value outside the range of values for the enum type is loaded, a run-time error is issued. -fsanitize=vptr This option enables instrumentation of C++ member function calls, member accesses and some conversions between pointers to base and derived classes, to verify the referenced object has the correct dynamic type. -fsanitize=pointer-overflow This option enables instrumentation of pointer arithmetics. If the pointer arithmetics overflows, a run-time error is issued. -fsanitize=builtin This option enables instrumentation of arguments to selected builtin functions. If an invalid value is passed to such arguments, a run-time error is issued. E.g. passing 0 as the argument to \"builtinctz\" or \"builtinclz\" invokes undefined behavior and is diagnosed by this option. Note that sanitizers tend to increase the rate of false positive warnings, most notably those around -Wmaybe-uninitialized. We recommend against combining -Werror and [the use of] sanitizers. While -ftrapv causes traps for signed overflows to be emitted, -fsanitize=undefined gives a diagnostic message. This currently works only for the C family of languages."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option disables all previously enabled sanitizers. -fsanitize=all is not allowed, as some sanitizers cannot be used together."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option forces GCC to use custom shadow offset in AddressSanitizer checks. It is useful for experimenting with different shadow memory layouts in Kernel AddressSanitizer."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Sanitize global variables in selected user-defined sections. si may contain wildcards."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "-fsanitize-recover= controls error recovery mode for sanitizers mentioned in comma- separated list of opts. Enabling this option for a sanitizer component causes it to attempt to continue running the program as if no error happened. This means multiple runtime errors can be reported in a single program run, and the exit code of the program may indicate success even when errors have been reported. The -fno-sanitize-recover= option can be used to alter this behavior: only the first detected error is reported and program then exits with a non-zero exit code. Currently this feature only works for -fsanitize=undefined (and its suboptions except for -fsanitize=unreachable and -fsanitize=return), -fsanitize=float-cast-overflow, -fsanitize=float-divide-by-zero, -fsanitize=bounds-strict, -fsanitize=kernel-address and -fsanitize=address. For these sanitizers error recovery is turned on by default, except -fsanitize=address, for which this feature is experimental. -fsanitize-recover=all and -fno-sanitize-recover=all is also accepted, the former enables recovery for all sanitizers that support it, the latter disables recovery for all sanitizers that support it. Even if a recovery mode is turned on the compiler side, it needs to be also enabled on the runtime library side, otherwise the failures are still fatal. The runtime library defaults to \"haltonerror=0\" for ThreadSanitizer and UndefinedBehaviorSanitizer, while default value for AddressSanitizer is \"haltonerror=1\". This can be overridden through setting the \"haltonerror\" flag in the corresponding environment variable. Syntax without an explicit opts parameter is deprecated. It is equivalent to specifying an opts list of: undefined,float-cast-overflow,float-divide-by-zero,bounds-strict"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable sanitization of local variables to detect use-after-scope bugs. The option sets -fstack-reuse to none."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The -fsanitize-trap= option instructs the compiler to report for sanitizers mentioned in comma-separated list of opts undefined behavior using \"builtintrap\" rather than a \"libubsan\" library routine. If this option is enabled for certain sanitizer, it takes precedence over the -fsanitizer-recover= for that sanitizer, \"builtintrap\" will be emitted and be fatal regardless of whether recovery is enabled or disabled using -fsanitize-recover=. The advantage of this is that the \"libubsan\" library is not needed and is not linked in, so this is usable even in freestanding environments. Currently this feature works with -fsanitize=undefined (and its suboptions except for -fsanitize=vptr), -fsanitize=float-cast-overflow, -fsanitize=float-divide-by-zero and -fsanitize=bounds-strict. \"-fsanitize-trap=all\" can be also specified, which enables it for \"undefined\" suboptions, -fsanitize=float-cast-overflow, -fsanitize=float-divide-by-zero and -fsanitize=bounds-strict. If \"-fsanitize-trap=undefined\" or \"-fsanitize-trap=all\" is used and \"-fsanitize=vptr\" is enabled on the command line, the instrumentation is silently ignored as the instrumentation always needs \"libubsan\" support, -fsanitize-trap=vptr is not allowed."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The -fsanitize-undefined-trap-on-error option is deprecated equivalent of -fsanitize-trap=all."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable coverage-guided fuzzing code instrumentation. Inserts a call to \"sanitizercovtracepc\" into every basic block."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable dataflow guided fuzzing code instrumentation. Inserts a call to \"sanitizercovtracecmp1\", \"sanitizercovtracecmp2\", \"sanitizercovtracecmp4\" or \"sanitizercovtracecmp8\" for integral comparison with both operands variable or \"sanitizercovtraceconstcmp1\", \"sanitizercovtraceconstcmp2\", \"sanitizercovtraceconstcmp4\" or \"sanitizercovtraceconstcmp8\" for integral comparison with one operand constant, \"sanitizercovtracecmpf\" or \"sanitizercovtracecmpd\" for float or double comparisons and \"sanitizercovtraceswitch\" for switch statements."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable code instrumentation of control-flow transfers to increase program security by checking that target addresses of control-flow transfer instructions (such as indirect function call, function return, indirect jump) are valid. This prevents diverting the flow of control to an unexpected target. This is intended to protect against such threats as Return-oriented Programming (ROP), and similarly call/jmp-oriented programming (COP/JOP). The value \"branch\" tells the compiler to implement checking of validity of control-flow transfer at the point of indirect branch instructions, i.e. call/jmp instructions. The value \"return\" implements checking of validity at the point of returning from a function. The value \"full\" is an alias for specifying both \"branch\" and \"return\". The value \"none\" turns off instrumentation. The value \"check\" is used for the final link with link-time optimization (LTO). An error is issued if LTO object files are compiled with different -fcf-protection values. The value \"check\" is ignored at the compile time. The macro \"CET\" is defined when -fcf-protection is used. The first bit of \"CET\" is set to 1 for the value \"branch\" and the second bit of \"CET\" is set to 1 for the \"return\". You can also use the \"nocfcheck\" attribute to identify which functions and calls should be skipped from instrumentation. Currently the x86 GNU/Linux target provides an implementation based on Intel Control-flow Enforcement Technology (CET) which works for i686 processor or newer. NOTE: In Ubuntu 19.10 and later versions, -fcf-protection is enabled by default for C, C++, ObjC, ObjC++, if none of -fno-cf-protection nor -fcf-protection=* are found."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "For every logical test that survives gimple optimizations and is not the condition in a conditional branch (for example, conditions tested for conditional moves, or to store in boolean variables), emit extra code to compute and verify the reversed condition, and to call \"builtintrap\" if the results do not match. Use with -fharden-conditional-branches to cover all conditionals."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "For every non-vectorized conditional branch that survives gimple optimizations, emit extra code to compute and verify the reversed condition, and to call \"builtintrap\" if the result is unexpected. Use with -fharden-compares to cover all conditionals."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit extra code to check for buffer overflows, such as stack smashing attacks. This is done by adding a guard variable to functions with vulnerable objects. This includes functions that call \"alloca\", and functions with buffers larger than or equal to 8 bytes. The guards are initialized when a function is entered and then checked when the function exits. If a guard check fails, an error message is printed and the program exits. Only variables that are actually allocated on the stack are considered, optimized away variables or variables allocated in registers don't count."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Like -fstack-protector except that all functions are protected."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Like -fstack-protector but includes additional functions to be protected --- those that have local array definitions, or have references to local frame addresses. Only variables that are actually allocated on the stack are considered, optimized away variables or variables allocated in registers don't count. NOTE: In Ubuntu 14.10 and later versions, -fstack-protector-strong is enabled by default for C, C++, ObjC, ObjC++, if none of -fno-stack-protector, -nostdlib, nor -ffreestanding are found."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Like -fstack-protector but only protects those functions which have the \"stackprotect\" attribute."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code to verify that you do not go beyond the boundary of the stack. You should specify this flag if you are running in an environment with multiple threads, but you only rarely need to specify it in a single-threaded environment since stack overflow is automatically detected on nearly all systems if there is only one stack. Note that this switch does not actually cause checking to be done; the operating system or the language runtime must do that. The switch causes generation of code to ensure that they see the stack being extended. You can additionally specify a string parameter: no means no checking, generic means force the use of old-style checking, specific means use the best checking method and is equivalent to bare -fstack-check. Old-style checking is a generic mechanism that requires no specific target support in the compiler but comes with the following drawbacks: 1. Modified allocation strategy for large objects: they are always allocated dynamically if their size exceeds a fixed threshold. Note this may change the semantics of some code. 2. Fixed limit on the size of the static frame of functions: when it is topped by a particular function, stack checking is not reliable and a warning is issued by the compiler. 3. Inefficiency: because of both the modified allocation strategy and the generic implementation, code performance is hampered. Note that old-style stack checking is also the fallback method for specific if no target support has been added in the compiler. -fstack-check= is designed for Ada's needs to detect infinite recursion and stack overflows. specific is an excellent choice when compiling Ada code. It is not generally sufficient to protect against stack-clash attacks. To protect against those you want -fstack-clash-protection."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code to prevent stack clash style attacks. When this option is enabled, the compiler will only allocate one page of stack space at a time and each page is accessed immediately after allocation. Thus, it prevents allocations from jumping over any stack guard page provided by the operating system. Most targets do not fully support stack clash protection. However, on those targets -fstack-clash-protection will protect dynamic stack allocations. -fstack-clash-protection may also provide limited protection for static stack allocations if the target supports -fstack-check=specific. NOTE: In Ubuntu 19.10 and later versions, -fstack-clash-protection is enabled by default for C, C++, ObjC, ObjC++, unless -fno-stack-clash-protection is found."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code to ensure that the stack does not grow beyond a certain value, either the value of a register or the address of a symbol. If a larger stack is required, a signal is raised at run time. For most targets, the signal is raised before the stack overruns the boundary, so it is possible to catch the signal without taking special precautions. For instance, if the stack starts at absolute address 0x80000000 and grows downwards, you can use the flags -fstack-limit-symbol=stacklimit and -Wl,--defsym,stacklimit=0x7ffe0000 to enforce a stack limit of 128KB. Note that this may only work with the GNU linker. You can locally override stack limit checking by using the \"nostacklimit\" function attribute."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code to automatically split the stack before it overflows. The resulting program has a discontiguous stack which can only overflow if the program is unable to allocate any more memory. This is most useful when running threaded programs, as it is no longer necessary to calculate a good stack size to use for each thread. This is currently only implemented for the x86 targets running GNU/Linux. When code compiled with -fsplit-stack calls code compiled without -fsplit-stack, there may not be much stack space available for the latter code to run. If compiling all code, including library code, with -fsplit-stack is not an option, then the linker can fix up these calls so that the code compiled without -fsplit-stack always has a large stack. Support for this is implemented in the gold linker in GNU binutils release 2.21 and later."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is only available when compiling C++ code. It turns on (or off, if using -fvtable-verify=none) the security feature that verifies at run time, for every virtual call, that the vtable pointer through which the call is made is valid for the type of the object, and has not been corrupted or overwritten. If an invalid vtable pointer is detected at run time, an error is reported and execution of the program is immediately halted. This option causes run-time data structures to be built at program startup, which are used for verifying the vtable pointers. The options std and preinit control the timing of when these data structures are built. In both cases the data structures are built before execution reaches \"main\". Using -fvtable-verify=std causes the data structures to be built after shared libraries have been loaded and initialized. -fvtable-verify=preinit causes them to be built before shared libraries have been loaded and initialized. If this option appears multiple times in the command line with different values specified, none takes highest priority over both std and preinit; preinit takes priority over std."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When used in conjunction with -fvtable-verify=std or -fvtable-verify=preinit, causes debug versions of the runtime functions for the vtable verification feature to be called. This flag also causes the compiler to log information about which vtable pointers it finds for each class. This information is written to a file named vtvsetptrdata.log in the directory named by the environment variable VTVLOGSDIR if that is defined or the current working directory otherwise. Note: This feature appends data to the log file. If you want a fresh log file, be sure to delete any existing one."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This is a debugging flag. When used in conjunction with -fvtable-verify=std or -fvtable-verify=preinit, this causes the compiler to keep track of the total number of virtual calls it encounters and the number of verifications it inserts. It also counts the number of calls to certain run-time library functions that it inserts and logs this information for each compilation unit. The compiler writes this information to a file named vtvcountdata.log in the directory named by the environment variable VTVLOGSDIR if that is defined or the current working directory otherwise. It also counts the size of the vtable pointer sets for each class, and writes this information to vtvclasssetsizes.log in the same directory. Note: This feature appends data to the log files. To get fresh log files, be sure to delete any existing ones."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate instrumentation calls for entry and exit to functions. Just after function entry and just before function exit, the following profiling functions are called with the address of the current function and its call site. (On some platforms, \"builtinreturnaddress\" does not work beyond the current function, so the call site information may not be available to the profiling functions otherwise.) void cygprofilefuncenter (void *thisfn, void *callsite); void cygprofilefuncexit (void *thisfn, void *callsite); The first argument is the address of the start of the current function, which may be looked up exactly in the symbol table. This instrumentation is also done for functions expanded inline in other functions. The profiling calls indicate where, conceptually, the inline function is entered and exited. This means that addressable versions of such functions must be available. If all your uses of a function are expanded inline, this may mean an additional expansion of code size. If you use \"extern inline\" in your C code, an addressable version of such functions must be provided. (This is normally the case anyway, but if you get lucky and the optimizer always expands the functions inline, you might have gotten away without providing static copies.) A function may be given the attribute \"noinstrumentfunction\", in which case this instrumentation is not done. This can be used, for example, for the profiling functions listed above, high-priority interrupt routines, and any functions from which the profiling functions cannot safely be called (perhaps signal handlers, if the profiling routines generate output or allocate memory)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This is similar to -finstrument-functions, but the profiling functions are called only once per instrumented function, i.e. the first profiling function is called after the first entry into the instrumented function and the second profiling function is called before the exit corresponding to this first entry. The definition of \"once\" for the purpose of this option is a little vague because the implementation is not protected against data races. As a result, the implementation only guarantees that the profiling functions are called at least once per process and at most once per thread, but the calls are always paired, that is to say, if a thread calls the first function, then it will call the second function, unless it never reaches the exit of the instrumented function."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the list of functions that are excluded from instrumentation (see the description of -finstrument-functions). If the file that contains a function definition matches with one of file, then that function is not instrumented. The match is done on substrings: if the file parameter is a substring of the file name, it is considered to be a match. For example: -finstrument-functions-exclude-file-list=/bits/stl,include/sys excludes any inline function defined in files whose pathnames contain /bits/stl or include/sys. If, for some reason, you want to include letter , in one of sym, write ,. For example, -finstrument-functions-exclude-file-list=',,tmp' (note the single quote surrounding the option)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This is similar to -finstrument-functions-exclude-file-list, but this option sets the list of function names to be excluded from instrumentation. The function name to be matched is its user-visible name, such as \"vector<int> blah(const vector<int> &)\", not the internal mangled name (e.g., \"Z4blahRSt6vectorIiSaIiEE\"). The match is done on substrings: if the sym parameter is a substring of the function name, it is considered to be a match. For C99 and C++ extended identifiers, the function name must be given in UTF-8, not using universal character names."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate N NOPs right at the beginning of each function, with the function entry point before the Mth NOP. If M is omitted, it defaults to 0 so the function entry points to the address just at the first NOP. The NOP instructions reserve extra space which can be used to patch in any desired instrumentation at run time, provided that the code segment is writable. The amount of space is controllable indirectly via the number of NOPs; the NOP instruction used corresponds to the instruction emitted by the internal GCC back-end interface \"gennop\". This behavior is target-specific and may also depend on the architecture variant and/or other compilation options. For run-time identification, the starting addresses of these areas, which correspond to their respective function entries minus M, are additionally collected in the \"patchablefunctionentries\" section of the resulting binary. Note that the value of \"attribute ((patchablefunctionentry (N,M)))\" takes precedence over command-line option -fpatchable-function-entry=N,M. This can be used to increase the area size or to remove it completely on a single function. If \"N=0\", no pad location is recorded. The NOP instructions are inserted at---and maybe before, depending on M---the function entry address, even before the prologue. On PowerPC with the ELFv2 ABI, for a function with dual entry points, the local entry point is this function entry address. The maximum value of N and M is 65535. On PowerPC with the ELFv2 ABI, for a function with dual entry points, the supported values for M are 0, 2, 6 and 14."
        },
        {
            "flag": "-D",
            "long": null,
            "arg": null,
            "description": "Predefine name as a macro, with definition 1."
        },
        {
            "flag": "-D",
            "long": null,
            "arg": null,
            "description": "The contents of definition are tokenized and processed as if they appeared during translation phase three in a #define directive. In particular, the definition is truncated by embedded newline characters. If you are invoking the preprocessor from a shell or shell-like program you may need to use the shell's quoting syntax to protect characters such as spaces that have a meaning in the shell syntax. If you wish to define a function-like macro on the command line, write its argument list with surrounding parentheses before the equals sign (if any). Parentheses are meaningful to most shells, so you should quote the option. With sh and csh, -D'name(args...)=definition' works. -D and -U options are processed in the order they are given on the command line. All -imacros file and -include file options are processed after all -D and -U options."
        },
        {
            "flag": "-U",
            "long": null,
            "arg": null,
            "description": "Cancel any previous definition of name, either built in or provided with a -D option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Process file as if \"#include \"file\"\" appeared as the first line of the primary source file. However, the first directory searched for file is the preprocessor's working directory instead of the directory containing the main source file. If not found there, it is searched for in the remainder of the \"#include \"...\"\" search chain as normal. If multiple -include options are given, the files are included in the order they appear on the command line."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Exactly like -include, except that any output produced by scanning file is thrown away. Macros it defines remain defined. This allows you to acquire all the macros from a header without also processing its declarations. All files specified by -imacros are processed before all files specified by -include."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not predefine any system-specific or GCC-specific macros. The standard predefined macros remain defined."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Define additional macros required for using the POSIX threads library. You should use this option consistently for both compilation and linking. This option is supported on GNU/Linux targets, most other Unix derivatives, and also on x86 Cygwin and MinGW targets."
        },
        {
            "flag": "-M",
            "long": null,
            "arg": null,
            "description": "describing the dependencies of the main source file. The preprocessor outputs one make rule containing the object file name for that source file, a colon, and the names of all the included files, including those coming from -include or -imacros command-line options. Unless specified explicitly (with -MT or -MQ), the object file name consists of the name of the source file with any suffix replaced with object file suffix and with any leading directory parts removed. If there are many included files then the rule is split into several lines using \\-newline. The rule has no commands. This option does not suppress the preprocessor's debug output, such as -dM. To avoid mixing such debug output with the dependency rules you should explicitly specify the dependency output file with -MF, or use an environment variable like DEPENDENCIESOUTPUT. Debug output is still sent to the regular output stream as normal. Passing -M to the driver implies -E, and suppresses warnings with an implicit -w."
        },
        {
            "flag": "-M",
            "long": null,
            "arg": null,
            "description": "header files that are included, directly or indirectly, from such a header. This implies that the choice of angle brackets or double quotes in an #include directive does not in itself determine whether that header appears in -MM dependency output."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When used with -M or -MM, specifies a file to write the dependencies to. If no -MF switch is given the preprocessor sends the rules to the same place it would send preprocessed output. When used with the driver options -MD or -MMD, -MF overrides the default dependency output file. If file is -, then the dependencies are written to stdout."
        },
        {
            "flag": "-M",
            "long": null,
            "arg": null,
            "description": "missing header files are generated files and adds them to the dependency list without raising an error. The dependency filename is taken directly from the \"#include\" directive without prepending any path. -MG also suppresses preprocessed output, as a missing header file renders this useless. This feature is used in automatic updating of makefiles."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable dependency generation for compiled module interfaces."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "file, causing each to depend on nothing. These dummy rules work around errors make gives if you remove header files without updating the Makefile to match. This is typical output: test.o: test.c test.h test.h:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Change the target of the rule emitted by dependency generation. By default CPP takes the name of the main input file, deletes any directory components and any file suffix such as .c, and appends the platform's usual object suffix. The result is the target. An -MT option sets the target to be exactly the string you specify. If you want multiple targets, you can specify them as a single argument to -MT, or use multiple -MT options. For example, -MT '$(objpfx)foo.o' might give $(objpfx)foo.o: foo.c"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Same as -MT, but it quotes any characters which are special to Make. -MQ '$(objpfx)foo.o' gives $$(objpfx)foo.o: foo.c The default target is automatically quoted, as if it were given with -MQ."
        },
        {
            "flag": "-E",
            "long": null,
            "arg": null,
            "description": "file based on whether an -o option is given. If it is, the driver uses its argument but with a suffix of .d, otherwise it takes the name of the input file, removes any directory components and suffix, and applies a .d suffix. If -MD is used in conjunction with -E, any -o switch is understood to specify the dependency output file, but if used without -E, each -o is understood to specify a target object file. Since -E is not implied, -MD can be used to generate a dependency output file as a side effect of the compilation process."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Like -MD except mention only user header files, not system header files."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Indicate to the preprocessor that the input file has already been preprocessed. This suppresses things like macro expansion, trigraph conversion, escaped newline splicing, and processing of most directives. The preprocessor still recognizes and removes comments, so that you can pass a file preprocessed with -C to the compiler without problems. In this mode the integrated preprocessor is little more than a tokenizer for the front ends. -fpreprocessed is implicit if the input file has one of the extensions .i, .ii or .mi. These are the extensions that GCC uses for preprocessed files created by -save-temps."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When preprocessing, handle directives, but do not expand macros. The option's behavior depends on the -E and -fpreprocessed options. With -E, preprocessing is limited to the handling of directives such as \"#define\", \"#ifdef\", and \"#error\". Other preprocessor operations, such as macro expansion and trigraph conversion are not performed. In addition, the -dD option is implicitly enabled. With -fpreprocessed, predefinition of command line and most builtin macros is disabled. Macros such as \"LINE\", which are contextually dependent, are handled normally. This enables compilation of files previously preprocessed with \"-E -fdirectives-only\". With both -E and -fpreprocessed, the rules for -fpreprocessed take precedence. This enables full preprocessing of files previously preprocessed with \"-E -fdirectives-only\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Accept $ in identifiers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Accept universal character names and extended characters in identifiers. This option is enabled by default for C99 (and later C standard versions) and C++."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When preprocessing, do not shorten system header paths with canonicalization."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the maximum depth of the nested #include. The default is 200."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the distance between tab stops. This helps the preprocessor report correct column numbers in warnings or errors, even if tabs appear on the line. If the value is less than 1 or greater than 100, the option is ignored. The default is 8."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Track locations of tokens across macro expansions. This allows the compiler to emit diagnostic about the current macro expansion stack when a compilation error occurs in a macro expansion. Using this option makes the preprocessor and the compiler consume more memory. The level parameter can be used to choose the level of precision of token location tracking thus decreasing the memory consumption if necessary. Value 0 of level de-activates this option. Value 1 tracks tokens locations in a degraded mode for the sake of minimal memory overhead. In this mode all tokens resulting from the expansion of an argument of a function-like macro have the same location. Value 2 tracks tokens locations completely. This value is the most memory hungry. When this option is given no argument, the default parameter value is 2. Note that \"-ftrack-macro-expansion=2\" is activated by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When preprocessing files residing in directory old, expand the \"FILE\" and \"BASEFILE\" macros as if the files resided in directory new instead. This can be used to change an absolute path to a relative path by using . for new which can result in more reproducible builds that are location independent. This option also affects \"builtinFILE()\" during compilation. See also -ffile-prefix-map and -fcanon-prefix-map."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the execution character set, used for string and character constants. The default is UTF-8. charset can be any encoding supported by the system's \"iconv\" library routine."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the wide execution character set, used for wide string and character constants. The default is one of UTF-32BE, UTF-32LE, UTF-16BE, or UTF-16LE, whichever corresponds to the width of \"wchart\" and the big-endian or little-endian byte order being used for code generation. As with -fexec-charset, charset can be any encoding supported by the system's \"iconv\" library routine; however, you will have problems with encodings that do not fit exactly in \"wchart\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the input character set, used for translation from the character set of the input file to the source character set used by GCC. If the locale does not specify, or GCC cannot get this information from the locale, the default is UTF-8. This can be overridden by either the locale or this command-line option. Currently the command-line option takes precedence if there's a conflict. charset can be any encoding supported by the system's \"iconv\" library routine."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When using precompiled headers, this flag causes the dependency-output flags to also list the files from the precompiled header's dependencies. If not specified, only the precompiled header are listed and not the files that were used to create it, because those files are not consulted when a precompiled header is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option allows use of a precompiled header together with -E. It inserts a special \"#pragma\", \"#pragma GCC pchpreprocess \"filename\"\" in the output to mark the place where the precompiled header was found, and its filename. When -fpreprocessed is in use, GCC recognizes this \"#pragma\" and loads the PCH. This option is off by default, because the resulting preprocessed output is only really suitable as input to GCC. It is switched on by -save-temps. You should not write this \"#pragma\" in your own code, but it is safe to edit the filename if the PCH file is available in a different location. The filename may be absolute or it may be relative to GCC's current directory."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable generation of linemarkers in the preprocessor output that let the compiler know the current working directory at the time of preprocessing. When this option is enabled, the preprocessor emits, after the initial linemarker, a second linemarker with the current working directory followed by two slashes. GCC uses this directory, when it's present in the preprocessed input, as the directory emitted as the current working directory in some debugging information formats. This option is implicitly enabled if debugging information is enabled, but this can be inhibited with the negated form -fno-working-directory. If the -P flag is present in the command line, this option has no effect, since no \"#line\" directives are emitted whatsoever."
        },
        {
            "flag": "-A",
            "long": null,
            "arg": null,
            "description": "Make an assertion with the predicate predicate and answer answer. This form is preferred to the older form -A predicate(answer), which is still supported, because it does not use shell special characters."
        },
        {
            "flag": "-A",
            "long": null,
            "arg": null,
            "description": "Cancel an assertion with the predicate predicate and answer answer."
        },
        {
            "flag": "-C",
            "long": null,
            "arg": null,
            "description": "comments in processed directives, which are deleted along with the directive. You should be prepared for side effects when using -C; it causes the preprocessor to treat comments as tokens in their own right. For example, comments appearing at the start of what would be a directive line have the effect of turning that line into an ordinary source line, since the first token on the line is no longer a #."
        },
        {
            "flag": "-C",
            "long": null,
            "arg": null,
            "description": "comments contained within macros are also passed through to the output file where the macro is expanded. In addition to the side effects of the -C option, the -CC option causes all C++-style comments inside a macro to be converted to C-style comments. This is to prevent later use of that macro from inadvertently commenting out the remainder of the source line. The -CC option is generally used to support lint comments."
        },
        {
            "flag": "-P",
            "long": null,
            "arg": null,
            "description": "useful when running the preprocessor on something that is not C code, and will be sent to a program which might be confused by the linemarkers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Try to imitate the behavior of pre-standard C preprocessors, as opposed to ISO C preprocessors. See the GNU CPP manual for details. Note that GCC does not otherwise attempt to emulate a pre-standard C compiler, and these options are only supported with the -E switch, or when invoking CPP explicitly."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Support ISO C trigraphs. These are three-character sequences, all starting with ??, that are defined by ISO C to stand for single characters. For example, ??/ stands for \\, so '??/n' is a character constant for a newline. The nine trigraphs and their replacements are Trigraph: ??( ??) ??< ??> ??= ??/ ??' ??! ??- Replacement: [ ] { } # \\ ^ | ~ By default, GCC ignores trigraphs, but in standard-conforming modes it converts them. See the -std and -ansi options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable special code to work around file systems which only permit very short file names, such as MS-DOS."
        },
        {
            "flag": "-H",
            "long": null,
            "arg": null,
            "description": "name is indented to show how deep in the #include stack it is. Precompiled header files are also printed, even if they are found to be invalid; an invalid precompiled header file is printed with ...x and a valid one with ...! ."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Says to make debugging dumps during compilation as specified by letters. The flags documented here are those relevant to the preprocessor. Other letters are interpreted by the compiler proper, or reserved for future versions of GCC, and so are silently ignored. If you specify letters whose behavior conflicts, the result is undefined. -dM Instead of the normal output, generate a list of #define directives for all the macros defined during the execution of the preprocessor, including predefined macros. This gives you a way of finding out what is predefined in your version of the preprocessor. Assuming you have no file foo.h, the command touch foo.h; cpp -dM foo.h shows all the predefined macros. If you use -dM without the -E option, -dM is interpreted as a synonym for -fdump-rtl-mach. -dD Like -dM except in two respects: it does not include the predefined macros, and it outputs both the #define directives and the result of preprocessing. Both kinds of output go to the standard output file. -dN Like -dD, but emit only the macro names, not their expansions. -dI Output #include directives in addition to the result of preprocessing. -dU Like -dD except that only macros that are expanded, or whose definedness is tested in preprocessor directives, are output; the output is delayed until the use or test of the macro; and #undef directives are also output for macros tested but undefined at the time."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is only useful for debugging GCC. When used from CPP or with -E, it dumps debugging information about location maps. Every token in the output is preceded by the dump of the map its location belongs to. When used from GCC without -E, this option has no effect."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "You can use -Wp,option to bypass the compiler driver and pass option directly through to the preprocessor. If option contains commas, it is split into multiple options at the commas. However, many options are modified, translated or interpreted by the compiler driver before being passed to the preprocessor, and -Wp forcibly bypasses this phase. The preprocessor's direct interface is undocumented and subject to change, so whenever possible you should avoid using -Wp and let the driver handle the options instead."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Pass option as an option to the preprocessor. You can use this to supply system-specific preprocessor options that GCC does not recognize. If you want to pass an option that takes an argument, you must use -Xpreprocessor twice, once for the option and once for the argument."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Perform preprocessing as a separate pass before compilation. By default, GCC performs preprocessing as an integrated part of input tokenization and parsing. If this option is provided, the appropriate language front end (cc1, cc1plus, or cc1obj for C, C++, and Objective-C, respectively) is instead invoked twice, once for preprocessing only and once for actual compilation of the preprocessed input. This option may be useful in conjunction with the -B or -wrapper options to specify an alternate preprocessor or perform additional processing of the program source between normal preprocessing and compilation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Adjust GCC to expect large source files, at the expense of slower compilation and higher memory usage. Specifically, GCC normally tracks both column numbers and line numbers within source files and it normally prints both of these numbers in diagnostics. However, once it has processed a certain number of source lines, it stops tracking column numbers and only tracks line numbers. This means that diagnostics for later lines do not include column numbers. It also means that options like -Wmisleading-indentation cease to work at that point, although the compiler prints a note if this happens. Passing -flarge-source-files significantly increases the number of source lines that GCC can process before it stops tracking columns."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Pass option as an option to the assembler. If option contains commas, it is split into multiple options at the commas."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Pass option as an option to the assembler. You can use this to supply system-specific assembler options that GCC does not recognize. If you want to pass an option that takes an argument, you must use -Xassembler twice, once for the option and once for the argument."
        },
        {
            "flag": "-c",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "-S",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "-E",
            "long": null,
            "arg": null,
            "description": "not be used as arguments."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls code generation of the link-time optimizer. By default the linker output is automatically determined by the linker plugin. For debugging the compiler and if incremental linking with a non-LTO object file is desired, it may be useful to control the type manually. If type is exec, code generation produces a static binary. In this case -fpic and -fpie are both disabled. If type is dyn, code generation produces a shared library. In this case -fpic or -fPIC is preserved, but not enabled automatically. This allows to build shared libraries without position-independent code on architectures where this is possible, i.e. on x86. If type is pie, code generation produces an -fpie executable. This results in similar optimizations as exec except that -fpie is not disabled if specified at compilation time. If type is rel, the compiler assumes that incremental linking is done. The sections containing intermediate code for link-time optimization are merged, pre-optimized, and output to the resulting object file. In addition, if -ffat-lto-objects is specified, binary code is produced for future non-LTO linking. The object file produced by incremental linking is smaller than a static library produced from the same object files. At link time the result of incremental linking also loads faster than a static library assuming that the majority of objects in the library are used. Finally nolto-rel configures the compiler for incremental linking where code generation is forced, a final binary is produced, and the intermediate code for later link-time optimization is stripped. When multiple object files are linked together the resulting code is better optimized than with link-time optimizations disabled (for example, cross- module inlining happens), but most of benefits of whole program optimizations are lost. During the incremental link (by -r) the linker plugin defaults to rel. With current interfaces to GNU Binutils it is however not possible to incrementally link LTO objects and non-LTO objects into a single mixed object file. If any of object files in incremental link cannot be used for link-time optimization, the linker plugin issues a warning and uses nolto-rel. To maintain whole program optimization, it is recommended to link such objects into static library instead. Alternatively it is possible to use H.J. Lu's binutils with support for mixed objects."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use the bfd linker instead of the default linker."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use the gold linker instead of the default linker."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use the LLVM lld linker instead of the default linker."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use the Modern Linker (mold) instead of the default linker."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "-l",
            "long": null,
            "arg": null,
            "description": "Search the library named library when linking. (The second alternative with the library as a separate argument is only for POSIX compliance and is not recommended.) The -l option is passed directly to the linker by GCC. Refer to your linker documentation for exact details. The general description below applies to the GNU linker. The linker searches a standard list of directories for the library. The directories searched include several standard system directories plus any that you specify with -L. Static libraries are archives of object files, and have file names like liblibrary.a. Some targets also support shared libraries, which typically have names like liblibrary.so. If both static and shared libraries are found, the linker gives preference to linking with the shared library unless the -static option is used. It makes a difference where in the command you write this option; the linker searches and processes libraries and object files in the order they are specified. Thus, foo.o -lz bar.o searches library z after file foo.o but before bar.o. If bar.o refers to functions in z, those functions may not be loaded."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "You need this special case of the -l option in order to link an Objective-C or Objective-C++ program."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use the standard system startup files when linking. The standard system libraries are used normally, unless -nostdlib, -nolibc, or -nodefaultlibs is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use the standard system libraries when linking. Only the libraries you specify are passed to the linker, and options specifying linkage of the system libraries, such as -static-libgcc or -shared-libgcc, are ignored. The standard startup files are used normally, unless -nostartfiles is used. The compiler may generate calls to \"memcmp\", \"memset\", \"memcpy\" and \"memmove\". These entries are usually resolved by entries in libc. These entry points should be supplied through some other mechanism when this option is specified."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use the C library or system libraries tightly coupled with it when linking. Still link with the startup files, libgcc or toolchain provided language support libraries such as libgnat, libgfortran or libstdc++ unless options preventing their inclusion are used as well. This typically removes -lc from the link command line, as well as system libraries that normally go with it and become meaningless when absence of a C library is assumed, for example -lpthread or -lm in some configurations. This is intended for bare- board targets when there is indeed no C library available."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use the standard system startup files or libraries when linking. No startup files and only the libraries you specify are passed to the linker, and options specifying linkage of the system libraries, such as -static-libgcc or -shared-libgcc, are ignored. The compiler may generate calls to \"memcmp\", \"memset\", \"memcpy\" and \"memmove\". These entries are usually resolved by entries in libc. These entry points should be supplied through some other mechanism when this option is specified. One of the standard libraries bypassed by -nostdlib and -nodefaultlibs is libgcc.a, a library of internal subroutines which GCC uses to overcome shortcomings of particular machines, or special needs for some languages. In most cases, you need libgcc.a even when you want to avoid other standard libraries. In other words, when you specify -nostdlib or -nodefaultlibs you should usually specify -lgcc as well. This ensures that you have no unresolved references to internal GCC library subroutines. (An example of such an internal subroutine is \"main\", used to ensure C++ constructors are called.)"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not implicitly link with standard C++ libraries."
        },
        {
            "flag": "-e",
            "long": null,
            "arg": null,
            "description": "--entry=entry Specify that the program entry point is entry. The argument is interpreted by the linker; the GNU linker accepts either a symbol name or an address."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Produce a dynamically linked position independent executable on targets that support it. For predictable results, you must also specify the same set of options used for compilation (-fpie, -fPIE, or model suboptions) when you specify this linker option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't produce a dynamically linked position independent executable."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Produce a static position independent executable on targets that support it. A static position independent executable is similar to a static executable, but can be loaded at any address without a dynamic linker. For predictable results, you must also specify the same set of options used for compilation (-fpie, -fPIE, or model suboptions) when you specify this linker option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Link with the POSIX threads library. This option is supported on GNU/Linux targets, most other Unix derivatives, and also on x86 Cygwin and MinGW targets. On some targets this option also sets flags for the preprocessor, so it should be used consistently for both compilation and linking."
        },
        {
            "flag": "-r",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Pass the flag -export-dynamic to the ELF linker, on targets that support it. This instructs the linker to add all symbols, not only used ones, to the dynamic symbol table. This option is needed for some uses of \"dlopen\" or to allow obtaining backtraces from within a program."
        },
        {
            "flag": "-s",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On systems that support dynamic linking, this overrides -pie and prevents linking with the shared libraries. On other systems, this option has no effect."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Produce a shared object which can then be linked with other objects to form an executable. Not all systems support this option. For predictable results, you must also specify the same set of options used for compilation (-fpic, -fPIC, or model suboptions) when you specify this linker option.[1]"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On systems that provide libgcc as a shared library, these options force the use of either the shared or static version, respectively. If no shared version of libgcc was built when the compiler was configured, these options have no effect. There are several situations in which an application should use the shared libgcc instead of the static version. The most common of these is when the application wishes to throw and catch exceptions across different shared libraries. In that case, each of the libraries as well as the application itself should use the shared libgcc. Therefore, the G++ driver automatically adds -shared-libgcc whenever you build a shared library or a main executable, because C++ programs typically use exceptions, so this is the right thing to do. If, instead, you use the GCC driver to create shared libraries, you may find that they are not always linked with the shared libgcc. If GCC finds, at its configuration time, that you have a non-GNU linker or a GNU linker that does not support option --eh-frame-hdr, it links the shared version of libgcc into shared libraries by default. Otherwise, it takes advantage of the linker and optimizes away the linking with the shared version of libgcc, linking with the static version of libgcc by default. This allows exceptions to propagate through such shared libraries, without incurring relocation costs at library load time. However, if a library or main executable is supposed to throw or catch exceptions, you must link it using the G++ driver, or using the option -shared-libgcc, such that it is linked with the shared libgcc."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When the -fsanitize=address option is used to link a program, the GCC driver automatically links against libasan. If libasan is available as a shared library, and the -static option is not used, then this links against the shared version of libasan. The -static-libasan option directs the GCC driver to link libasan statically, without necessarily linking other libraries statically."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When the -fsanitize=thread option is used to link a program, the GCC driver automatically links against libtsan. If libtsan is available as a shared library, and the -static option is not used, then this links against the shared version of libtsan. The -static-libtsan option directs the GCC driver to link libtsan statically, without necessarily linking other libraries statically."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When the -fsanitize=leak option is used to link a program, the GCC driver automatically links against liblsan. If liblsan is available as a shared library, and the -static option is not used, then this links against the shared version of liblsan. The -static-liblsan option directs the GCC driver to link liblsan statically, without necessarily linking other libraries statically."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When the -fsanitize=undefined option is used to link a program, the GCC driver automatically links against libubsan. If libubsan is available as a shared library, and the -static option is not used, then this links against the shared version of libubsan. The -static-libubsan option directs the GCC driver to link libubsan statically, without necessarily linking other libraries statically."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When the g++ program is used to link a C++ program, it normally automatically links against libstdc++. If libstdc++ is available as a shared library, and the -static option is not used, then this links against the shared version of libstdc++. That is normally fine. However, it is sometimes useful to freeze the version of libstdc++ used by the program without going all the way to a fully static link. The -static-libstdc++ option directs the g++ driver to link libstdc++ statically, without necessarily linking other libraries statically."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Bind references to global symbols when building a shared object. Warn about any unresolved references (unless overridden by the link editor option -Xlinker -z -Xlinker defs). Only a few systems support this option."
        },
        {
            "flag": "-T",
            "long": null,
            "arg": null,
            "description": "Use script as the linker script. This option is supported by most systems using the GNU linker. On some targets, such as bare-board targets without an operating system, the -T option may be required when linking to avoid references to undefined symbols."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Pass option as an option to the linker. You can use this to supply system-specific linker options that GCC does not recognize. If you want to pass an option that takes a separate argument, you must use -Xlinker twice, once for the option and once for the argument. For example, to pass -assert definitions, you must write -Xlinker -assert -Xlinker definitions. It does not work to write -Xlinker \"-assert definitions\", because this passes the entire string as a single argument, which is not what the linker expects. When using the GNU linker, it is usually more convenient to pass arguments to linker options using the option=value syntax than as separate arguments. For example, you can specify -Xlinker -Map=output.map rather than -Xlinker -Map -Xlinker output.map. Other linkers may not support this syntax for command-line options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Pass option as an option to the linker. If option contains commas, it is split into multiple options at the commas. You can use this syntax to pass an argument to the option. For example, -Wl,-Map,output.map passes -Map output.map to the linker. When using the GNU linker, you can also get the same effect with -Wl,-Map=output.map. NOTE: In Ubuntu 8.10 and later versions, for LDFLAGS, the option -Wl,-z,relro is used. To disable, use -Wl,-z,norelro."
        },
        {
            "flag": "-u",
            "long": null,
            "arg": null,
            "description": "Pretend the symbol symbol is undefined, to force linking of library modules to define it. You can use -u multiple times with different symbols to force loading of additional library modules."
        },
        {
            "flag": "-z",
            "long": null,
            "arg": null,
            "description": "-z is passed directly on to the linker along with the keyword keyword. See the section in the documentation of your linker for permitted values and their meanings."
        },
        {
            "flag": "-I",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Add the directory dir to the list of directories to be searched for header files during preprocessing. If dir begins with = or $SYSROOT, then the = or $SYSROOT is replaced by the sysroot prefix; see --sysroot and -isysroot. Directories specified with -iquote apply only to the quote form of the directive, \"#include \"file\"\". Directories specified with -I, -isystem, or -idirafter apply to lookup for both the \"#include \"file\"\" and \"#include <file>\" directives. You can specify any number or combination of these options on the command line to search for header files in several directories. The lookup order is as follows: 1. For the quote form of the include directive, the directory of the current file is searched first. 2. For the quote form of the include directive, the directories specified by -iquote options are searched in left-to-right order, as they appear on the command line. 3. Directories specified with -I options are scanned in left-to-right order. 4. Directories specified with -isystem options are scanned in left-to-right order. 5. Standard system directories are scanned. 6. Directories specified with -idirafter options are scanned in left-to-right order. You can use -I to override a system header file, substituting your own version, since these directories are searched before the standard system header file directories. However, you should not use this option to add directories that contain vendor-supplied system header files; use -isystem for that. The -isystem and -idirafter options also mark the directory as a system directory, so that it gets the same special treatment that is applied to the standard system directories. If a standard system include directory, or a directory specified with -isystem, is also specified with -I, the -I option is ignored. The directory is still searched but as a system directory at its normal position in the system include chain. This is to ensure that GCC's procedure to fix buggy system headers and the ordering for the \"#includenext\" directive are not inadvertently changed. If you really need to change the search order for system directories, use the -nostdinc and/or -isystem options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "-I directories before the -I- and remove the -I- option. Any directories specified with -I options before -I- are searched only for headers requested with \"#include \"file\"\"; they are not searched for \"#include <file>\". If additional directories are specified with -I options after the -I-, those directories are searched for all #include directives. In addition, -I- inhibits the use of the directory of the current file directory as the first search directory for \"#include \"file\"\". There is no way to override this effect of -I-."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify prefix as the prefix for subsequent -iwithprefix options. If the prefix represents a directory, you should include the final /."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Append dir to the prefix specified previously with -iprefix, and add the resulting directory to the include search path. -iwithprefixbefore puts it in the same place -I would; -iwithprefix puts it where -idirafter would."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is like the --sysroot option, but applies only to header files (except for Darwin targets, where it applies to both header files and libraries). See the --sysroot option for more information."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use dir as a subdirectory of the directory containing target-specific C++ headers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not search the standard system directories for header files. Only the directories explicitly specified with -I, -iquote, -isystem, and/or -idirafter options (and the directory of the current file, if appropriate) are searched."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not search for header files in the C++-specific standard directories, but do still search the other standard directories. (This option is used when building the C++ library.)"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the directory to search for plugins that are passed by -fplugin=name instead of -fplugin=path/name.so. This option is not meant to be used by the user, but only passed by the driver."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Add directory dir to the list of directories to be searched for -l."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option specifies where to find the executables, libraries, include files, and data files of the compiler itself. The compiler driver program runs one or more of the subprograms cpp, cc1, as and ld. It tries prefix as a prefix for each program it tries to run, both with and without machine/version/ for the corresponding target machine and compiler version. For each subprogram to be run, the compiler driver first tries the -B prefix, if any. If that name is not found, or if -B is not specified, the driver tries two standard prefixes, /usr/lib/gcc/ and /usr/local/lib/gcc/. If neither of those results in a file name that is found, the unmodified program name is searched for using the directories specified in your PATH environment variable. The compiler checks to see if the path provided by -B refers to a directory, and if necessary it adds a directory separator character at the end of the path. -B prefixes that effectively specify directory names also apply to libraries in the linker, because the compiler translates these options into -L options for the linker. They also apply to include files in the preprocessor, because the compiler translates these options into -isystem options for the preprocessor. In this case, the compiler appends include to the prefix. The runtime support file libgcc.a can also be searched for using the -B prefix, if needed. If it is not found there, the two standard prefixes above are tried, and that is all. The file is left out of the link if it is not found by those means. Another way to specify a prefix much like the -B prefix is to use the environment variable GCCEXECPREFIX. As a special kludge, if the path provided by -B is [dir/]stageN/, where N is a number in the range 0 to 9, then it is replaced by [dir/]include. This is to help with boot- strapping the compiler."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not expand any symbolic links, resolve references to /../ or /./, or make the path absolute when generating a relative prefix. --sysroot=dir Use dir as the logical root directory for headers and libraries. For example, if the compiler normally searches for headers in /usr/include and libraries in /usr/lib, it instead searches dir/usr/include and dir/usr/lib. If you use both this option and the -isysroot option, then the --sysroot option applies to libraries, but the -isysroot option applies to header files. The GNU linker (beginning with version 2.16) has the necessary support for this option. If your linker does not support this option, the header file aspect of --sysroot still works, but the library aspect does not."
        },
        {
            "flag": "",
            "long": "--no-sysroot-suffix",
            "arg": null,
            "description": "For some targets, a suffix is added to the root directory specified with --sysroot, depending on the other options used, so that headers may for example be found in dir/suffix/usr/include instead of dir/usr/include. This option disables the addition of such a suffix."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls stack space reuse for user declared local/auto variables and compiler generated temporaries. reuselevel can be all, namedvars, or none. all enables stack reuse for all local variables and temporaries, namedvars enables the reuse only for user defined local variables with names, and none disables stack reuse completely. The default value is all. The option is needed when the program extends the lifetime of a scoped local variable or a compiler generated temporary beyond the end point defined by the language. When a lifetime of a variable ends, and if the variable lives in memory, the optimizing compiler has the freedom to reuse its stack space with other temporaries or scoped local variables whose live range does not overlap with it. Legacy code extending local lifetime is likely to break with the stack reuse optimization. For example, int *p; { int local1; p = &local1; local1 = 10; .... } { int local2; local2 = 20; ... } if (*p == 10) // out of scope use of local1 { } Another example: struct A { A(int k) : i(k), j(k) { } int i; int j; }; A *ap; void foo(const A& ar) { ap = &ar; } void bar() { foo(A(10)); // temp object's lifetime ends when foo returns { A a(20); .... } ap->i+= 10; // ap references out of scope temp whose space // is reused with a. What is the value of ap->i? } The lifetime of a compiler generated temporary is well defined by the C++ standard. When a lifetime of a temporary ends, and if the temporary lives in memory, the optimizing compiler has the freedom to reuse its stack space with other temporaries or scoped local variables whose live range does not overlap with it. However some of the legacy code relies on the behavior of older compilers in which temporaries' stack space is not reused, the aggressive stack reuse can lead to runtime errors. This option is used to control the temporary stack reuse optimization."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option generates traps for signed overflow on addition, subtraction, multiplication operations. The options -ftrapv and -fwrapv override each other, so using -ftrapv -fwrapv on the command-line results in -fwrapv being effective. Note that only active options override, so using -ftrapv -fwrapv -fno-wrapv on the command-line results in -ftrapv being effective."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option instructs the compiler to assume that signed arithmetic overflow of addition, subtraction and multiplication wraps around using twos-complement representation. This flag enables some optimizations and disables others. The options -ftrapv and -fwrapv override each other, so using -ftrapv -fwrapv on the command-line results in -fwrapv being effective. Note that only active options override, so using -ftrapv -fwrapv -fno-wrapv on the command-line results in -ftrapv being effective."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option instructs the compiler to assume that pointer arithmetic overflow on addition and subtraction wraps around using twos-complement representation. This flag disables some optimizations which assume pointer overflow is invalid."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option implies -fno-wrapv -fno-wrapv-pointer and when negated implies -fwrapv -fwrapv-pointer."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable exception handling. Generates extra code needed to propagate exceptions. For some targets, this implies GCC generates frame unwind information for all functions, which can produce significant data size overhead, although it does not affect execution. If you do not specify this option, GCC enables it by default for languages like C++ that normally require exception handling, and disables it for languages like C that do not normally require it. However, you may need to enable this option when compiling C code that needs to interoperate properly with exception handlers written in C++. You may also wish to disable this option if you are compiling older C++ programs that don't use exception handling."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that allows trapping instructions to throw exceptions. Note that this requires platform-specific runtime support that does not exist everywhere. Moreover, it only allows trapping instructions to throw exceptions, i.e. memory references or floating-point instructions. It does not allow exceptions to be thrown from arbitrary signal handlers such as \"SIGALRM\". This enables -fexceptions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Consider that instructions that may throw exceptions but don't otherwise contribute to the execution of the program can be optimized away. This does not affect calls to functions except those with the \"pure\" or \"const\" attributes. This option is enabled by default for the Ada and C++ compilers, as permitted by the language specifications. Optimization passes that cause dead exceptions to be removed are enabled independently at different optimization levels."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Similar to -fexceptions, except that it just generates any needed static data, but does not affect the generated code in any other way. You normally do not need to enable this option; instead, a language processor that needs this handling enables it on your behalf."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate unwind table in DWARF format, if supported by target machine. The table is exact at each instruction boundary, so it can be used for stack unwinding from asynchronous events (such as debugger or garbage collector)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On systems with recent GNU assembler and C library, the C++ compiler uses the \"STBGNUUNIQUE\" binding to make sure that definitions of template static data members and static local variables in inline functions are unique even in the presence of \"RTLDLOCAL\"; this is necessary to avoid problems with a library used by two different \"RTLDLOCAL\" plugins depending on a definition in one of them and therefore disagreeing with the other one about the binding of the symbol. But this causes \"dlclose\" to be ignored for affected DSOs; if your program relies on reinitialization of a DSO via \"dlclose\" and \"dlopen\", you can use -fno-gnu-unique."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Return \"short\" \"struct\" and \"union\" values in memory like longer ones, rather than in registers. This convention is less efficient, but it has the advantage of allowing intercallability between GCC-compiled files and files compiled with other compilers, particularly the Portable C Compiler (pcc). The precise convention for returning structures in memory depends on the target configuration macros. Short structures and unions are those whose size and alignment match that of some integer type. Warning: code compiled with the -fpcc-struct-return switch is not binary compatible with code compiled with the -freg-struct-return switch. Use it to conform to a non-default application binary interface."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Return \"struct\" and \"union\" values in registers when possible. This is more efficient for small structures than -fpcc-struct-return. If you specify neither -fpcc-struct-return nor -freg-struct-return, GCC defaults to whichever convention is standard for the target. If there is no standard convention, GCC defaults to -fpcc-struct-return, except on targets where GCC is the principal compiler. In those cases, we can choose the standard, and we chose the more efficient register return alternative. Warning: code compiled with the -freg-struct-return switch is not binary compatible with code compiled with the -fpcc-struct-return switch. Use it to conform to a non-default application binary interface."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allocate to an \"enum\" type only as many bytes as it needs for the declared range of possible values. Specifically, the \"enum\" type is equivalent to the smallest integer type that has enough room. Warning: the -fshort-enums switch causes GCC to generate code that is not binary compatible with code generated without that switch. Use it to conform to a non-default application binary interface."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Override the underlying type for \"wchart\" to be \"short unsigned int\" instead of the default for the target. This option is useful for building programs to run under WINE. Warning: the -fshort-wchar switch causes GCC to generate code that is not binary compatible with code generated without that switch. Use it to conform to a non-default application binary interface."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "In C code, this option controls the placement of global variables defined without an initializer, known as tentative definitions in the C standard. Tentative definitions are distinct from declarations of a variable with the \"extern\" keyword, which do not allocate storage. The default is -fno-common, which specifies that the compiler places uninitialized global variables in the BSS section of the object file. This inhibits the merging of tentative definitions by the linker so you get a multiple-definition error if the same variable is accidentally defined in more than one compilation unit. The -fcommon places uninitialized global variables in a common block. This allows the linker to resolve all tentative definitions of the same variable in different compilation units to the same object, or to a non-tentative definition. This behavior is inconsistent with C++, and on many targets implies a speed and code size penalty on global variable references. It is mainly useful to enable legacy code to link without errors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Ignore the \"#ident\" directive."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't output a \".size\" assembler directive, or anything else that would cause trouble if the function is split in the middle, and the two halves are placed at locations far apart in memory. This option is used when compiling crtstuff.c; you should not need to use it for anything else."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Put extra commentary information in the generated assembly code to make it more readable. This option is generally only of use to those who actually need to read the generated assembly code (perhaps while debugging the compiler itself). -fno-verbose-asm, the default, causes the extra information to be omitted and is useful when comparing two assembler files. The added comments include: * information on the compiler version and command-line options, * the source code lines associated with the assembly instructions, in the form FILENAME:LINENUMBER:CONTENT OF LINE, * hints on which high-level expressions correspond to the various assembly instruction operands. For example, given this C source file: int test (int n) { int i; int total = 0; for (i = 0; i < n; i++) total += i * i; return total; } compiling to (x8664) assembly via -S and emitting the result direct to stdout via -o - gcc -S test.c -fverbose-asm -Os -o - gives output similar to this: .file \"test.c\" # GNU C11 (GCC) version 7.0.0 20160809 (experimental) (x8664-pc-linux-gnu) [...snip...] # options passed: [...snip...] .text .globl test .type test, @function test: .LFB0: .cfistartproc # test.c:4: int total = 0; xorl %eax, %eax # <retval> # test.c:6: for (i = 0; i < n; i++) xorl %edx, %edx # i .L2: # test.c:6: for (i = 0; i < n; i++) cmpl %edi, %edx # n, i jge .L5 #, # test.c:7: total += i * i; movl %edx, %ecx # i, tmp92 imull %edx, %ecx # i, tmp92 # test.c:6: for (i = 0; i < n; i++) incl %edx # i # test.c:7: total += i * i; addl %ecx, %eax # tmp92, <retval> jmp .L2 # .L5: # test.c:10: } ret .cfiendproc .LFE0: .size test, .-test .ident \"GCC: (GNU) 7.0.0 20160809 (experimental)\" .section .note.GNU-stack,\"\",@progbits The comments are intended for humans rather than machines and hence the precise format of the comments is subject to change."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This switch causes the command line used to invoke the compiler to be recorded into the object file that is being created. This switch is only implemented on some targets and the exact format of the recording is target and binary file format dependent, but it usually takes the form of a section containing ASCII text. This switch is related to the -fverbose-asm switch, but that switch only records information in the assembler output file as comments, so it never reaches the object file. See also -grecord-gcc-switches for another way of storing compiler options into the object file."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate position-independent code (PIC) suitable for use in a shared library, if supported for the target machine. Such code accesses all constant addresses through a global offset table (GOT). The dynamic loader resolves the GOT entries when the program starts (the dynamic loader is not part of GCC; it is part of the operating system). If the GOT size for the linked executable exceeds a machine-specific maximum size, you get an error message from the linker indicating that -fpic does not work; in that case, recompile with -fPIC instead. (These maximums are 8k on the SPARC, 28k on AArch64 and 32k on the m68k and RS/6000. The x86 has no such limit.) Position-independent code requires special support, and therefore works only on certain machines. For the x86, GCC supports PIC for System V but not for the Sun 386i. Code generated for the IBM RS/6000 is always position-independent. When this flag is set, the macros \"pic\" and \"PIC\" are defined to 1."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If supported for the target machine, emit position-independent code, suitable for dynamic linking and avoiding any limit on the size of the global offset table. This option makes a difference on AArch64, m68k, PowerPC and SPARC. Position-independent code requires special support, and therefore works only on certain machines. When this flag is set, the macros \"pic\" and \"PIC\" are defined to 2."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These options are similar to -fpic and -fPIC, but the generated position-independent code can be only linked into executables. Usually these options are used to compile code that will be linked using the -pie GCC option. -fpie and -fPIE both define the macros \"pie\" and \"PIE\". The macros have the value 1 for -fpie and 2 for -fPIE."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use the PLT for external function calls in position-independent code. Instead, load the callee address at call sites from the GOT and branch to it. This leads to more efficient code by eliminating PLT stubs and exposing GOT loads to optimizations. On architectures such as 32-bit x86 where PLT stubs expect the GOT pointer in a specific register, this gives more register allocation freedom to the compiler. Lazy binding requires use of the PLT; with -fno-plt all external symbols are resolved at load time. Alternatively, the function attribute \"noplt\" can be used to avoid calls through the PLT for specific external functions. In position-dependent code, a few targets also convert calls to functions that are marked to not use the PLT to use the GOT instead."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use jump tables for switch statements even where it would be more efficient than other code generation strategies. This option is of use in conjunction with -fpic or -fPIC for building code that forms part of a dynamic linker and cannot reference the address of a jump table. On some targets, jump tables do not require a GOT and this option is not needed."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use bit tests for switch statements even where it would be more efficient than other code generation strategies."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Treat the register named reg as a fixed register; generated code should never refer to it (except perhaps as a stack pointer, frame pointer or in some other fixed role). reg must be the name of a register. The register names accepted are machine-specific and are defined in the \"REGISTERNAMES\" macro in the machine description macro file. This flag does not have a negative form, because it specifies a three-way choice."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Treat the register named reg as an allocable register that is clobbered by function calls. It may be allocated for temporaries or variables that do not live across a call. Functions compiled this way do not save and restore the register reg. It is an error to use this flag with the frame pointer or stack pointer. Use of this flag for other registers that have fixed pervasive roles in the machine's execution model produces disastrous results. This flag does not have a negative form, because it specifies a three-way choice."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Treat the register named reg as an allocable register saved by functions. It may be allocated even for temporaries or variables that live across a call. Functions compiled this way save and restore the register reg if they use it. It is an error to use this flag with the frame pointer or stack pointer. Use of this flag for other registers that have fixed pervasive roles in the machine's execution model produces disastrous results. A different sort of disaster results from the use of this flag for a register in which function values may be returned. This flag does not have a negative form, because it specifies a three-way choice."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Without a value specified, pack all structure members together without holes. When a value is specified (which must be a small power of two), pack structure members according to this value, representing the maximum alignment (that is, objects with default alignment requirements larger than this are output potentially unaligned at the next fitting location. Warning: the -fpack-struct switch causes GCC to generate code that is not binary compatible with code generated without that switch. Additionally, it makes the code suboptimal. Use it to conform to a non-default application binary interface."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option and its counterpart, -fno-leading-underscore, forcibly change the way C symbols are represented in the object file. One use is to help link with legacy assembly code. Warning: the -fleading-underscore switch causes GCC to generate code that is not binary compatible with code generated without that switch. Use it to conform to a non-default application binary interface. Not all targets provide complete support for this switch."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Alter the thread-local storage model to be used. The model argument should be one of global-dynamic, local-dynamic, initial-exec or local-exec. Note that the choice is subject to optimization: the compiler may use a more efficient model for symbols not visible outside of the translation unit, or if -fpic is not given on the command line. The default without -fpic is initial-exec; with -fpic the default is global-dynamic."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "For targets that normally need trampolines for nested functions, always generate them instead of using descriptors. Otherwise, for targets that do not need them, like for example HP-PA or IA-64, do nothing. A trampoline is a small piece of code that is created at run time on the stack when the address of a nested function is taken, and is used to call the nested function indirectly. Therefore, it requires the stack to be made executable in order for the program to work properly. -fno-trampolines is enabled by default on a language by language basis to let the compiler avoid generating them, if it computes that this is safe, and replace them with descriptors. Descriptors are made up of data only, but the generated code must be prepared to deal with them. As of this writing, -fno-trampolines is enabled by default only for Ada. Moreover, code compiled with -ftrampolines and code compiled with -fno-trampolines are not binary compatible if nested functions are present. This option must therefore be used on a program-wide basis and be manipulated with extreme care. For languages other than Ada, the \"-ftrampolines\" and \"-fno-trampolines\" options currently have no effect, and trampolines are always generated on platforms that need them for nested functions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the default ELF image symbol visibility to the specified option---all symbols are marked with this unless overridden within the code. Using this feature can very substantially improve linking and load times of shared object libraries, produce more optimized code, provide near-perfect API export and prevent symbol clashes. It is strongly recommended that you use this in any shared objects you distribute. Despite the nomenclature, default always means public; i.e., available to be linked against from outside the shared object. protected and internal are pretty useless in real-world usage so the only other commonly used option is hidden. The default if -fvisibility isn't specified is default, i.e., make every symbol public. A good explanation of the benefits offered by ensuring ELF symbols have the correct visibility is given by \"How To Write Shared Libraries\" by Ulrich Drepper (which can be found at <https://www.akkadia.org/drepper/>)---however a superior solution made possible by this option to marking things hidden when the default is public is to make the default hidden and mark things public. This is the norm with DLLs on Windows and with -fvisibility=hidden and \"attribute ((visibility(\"default\")))\" instead of \"declspec(dllexport)\" you get almost identical semantics with identical syntax. This is a great boon to those working with cross-platform projects. For those adding visibility support to existing code, you may find \"#pragma GCC visibility\" of use. This works by you enclosing the declarations you wish to set visibility for with (for example) \"#pragma GCC visibility push(hidden)\" and \"#pragma GCC visibility pop\". Bear in mind that symbol visibility should be viewed as part of the API interface contract and thus all new code should always specify visibility when it is not the default; i.e., declarations only for use within the local DSO should always be marked explicitly as hidden as so to avoid PLT indirection overheads---making this abundantly clear also aids readability and self-documentation of the code. Note that due to ISO C++ specification requirements, \"operator new\" and \"operator delete\" must always be of default visibility. Be aware that headers from outside your project, in particular system headers and headers from any other library you use, may not be expecting to be compiled with visibility other than the default. You may need to explicitly say \"#pragma GCC visibility push(default)\" before including any such headers. \"extern\" declarations are not affected by -fvisibility, so a lot of code can be recompiled with -fvisibility=hidden with no modifications. However, this means that calls to \"extern\" functions with no explicit visibility use the PLT, so it is more effective to use \"attribute ((visibility))\" and/or \"#pragma GCC visibility\" to tell the compiler which \"extern\" declarations should be treated as hidden. Note that -fvisibility does affect C++ vague linkage entities. This means that, for instance, an exception class that is be thrown between DSOs must be explicitly marked with default visibility so that the typeinfo nodes are unified between the DSOs. An overview of these techniques, their benefits and how to use them is at <https://gcc.gnu.org/wiki/Visibility>."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option should be used if accesses to volatile bit-fields (or other structure fields, although the compiler usually honors those types anyway) should use a single access of the width of the field's type, aligned to a natural alignment if possible. For example, targets with memory-mapped peripheral registers might require all such accesses to be 16 bits wide; with this flag you can declare all peripheral bit-fields as \"unsigned short\" (assuming short is 16 bits on these targets) to force GCC to use 16-bit accesses instead of, perhaps, a more efficient 32-bit access. If this option is disabled, the compiler uses the most efficient instruction. In the previous example, that might be a 32-bit load instruction, even though that accesses bytes that do not contain any portion of the bit-field, or memory-mapped registers unrelated to the one being updated. In some cases, such as when the \"packed\" attribute is applied to a structure field, it may not be possible to access the field with a single read or write that is correctly aligned for the target machine. In this case GCC falls back to generating multiple accesses rather than code that will fault or truncate the result at run time. Note: Due to restrictions of the C/C++11 memory model, write accesses are not allowed to touch non bit-field members. It is therefore recommended to define all bits of the field's type as bit-field members. The default value of this option is determined by the application binary interface for the target processor."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls whether any out-of-line instance of the \"sync\" family of functions may be used to implement the C++11 \"atomic\" family of functions. The default value of this option is enabled, thus the only useful form of the option is -fno-sync-libcalls. This option is used in the implementation of the libatomic runtime library."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Makes the compiler output callgraph information for the program, on a per-object-file basis. The information is generated in the common VCG format. It can be decorated with additional, per-node and/or per-edge information, if a list of comma-separated markers is additionally specified. When the \"su\" marker is specified, the callgraph is decorated with stack usage information; it is equivalent to -fstack-usage. When the \"da\" marker is specified, the callgraph is decorated with information about dynamically allocated objects. When compiling with -flto, no callgraph information is output along with the object file. At LTO link time, -fcallgraph-info may generate multiple callgraph information files next to intermediate LTO output files."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Says to make debugging dumps during compilation at times specified by letters. This is used for debugging the RTL-based passes of the compiler. Some -dletters switches have different meaning when -E is used for preprocessing. Debug dumps can be enabled with a -fdump-rtl switch or some -d option letters. Here are the possible letters for use in pass and letters, and their meanings: -fdump-rtl-alignments Dump after branch alignments have been computed. -fdump-rtl-asmcons Dump after fixing rtl statements that have unsatisfied in/out constraints. -fdump-rtl-autoincdec Dump after auto-inc-dec discovery. This pass is only run on architectures that have auto inc or auto dec instructions. -fdump-rtl-barriers Dump after cleaning up the barrier instructions. -fdump-rtl-bbpart Dump after partitioning hot and cold basic blocks. -fdump-rtl-bbro Dump after block reordering. -fdump-rtl-btl1 -fdump-rtl-btl2 -fdump-rtl-btl1 and -fdump-rtl-btl2 enable dumping after the two branch target load optimization passes. -fdump-rtl-bypass Dump after jump bypassing and control flow optimizations. -fdump-rtl-combine Dump after the RTL instruction combination pass. -fdump-rtl-compgotos Dump after duplicating the computed gotos. -fdump-rtl-ce1 -fdump-rtl-ce2 -fdump-rtl-ce3 -fdump-rtl-ce1, -fdump-rtl-ce2, and -fdump-rtl-ce3 enable dumping after the three if conversion passes. -fdump-rtl-cprophardreg Dump after hard register copy propagation. -fdump-rtl-csa Dump after combining stack adjustments. -fdump-rtl-cse1 -fdump-rtl-cse2 -fdump-rtl-cse1 and -fdump-rtl-cse2 enable dumping after the two common subexpression elimination passes. -fdump-rtl-dce Dump after the standalone dead code elimination passes. -fdump-rtl-dbr Dump after delayed branch scheduling. -fdump-rtl-dce1 -fdump-rtl-dce2 -fdump-rtl-dce1 and -fdump-rtl-dce2 enable dumping after the two dead store elimination passes. -fdump-rtl-eh Dump after finalization of EH handling code. -fdump-rtl-ehranges Dump after conversion of EH handling range regions. -fdump-rtl-expand Dump after RTL generation. -fdump-rtl-fwprop1 -fdump-rtl-fwprop2 -fdump-rtl-fwprop1 and -fdump-rtl-fwprop2 enable dumping after the two forward propagation passes. -fdump-rtl-gcse1 -fdump-rtl-gcse2 -fdump-rtl-gcse1 and -fdump-rtl-gcse2 enable dumping after global common subexpression elimination. -fdump-rtl-init-regs Dump after the initialization of the registers. -fdump-rtl-initvals Dump after the computation of the initial value sets. -fdump-rtl-intocfglayout Dump after converting to cfglayout mode. -fdump-rtl-ira Dump after iterated register allocation. -fdump-rtl-jump Dump after the second jump optimization. -fdump-rtl-loop2 -fdump-rtl-loop2 enables dumping after the rtl loop optimization passes. -fdump-rtl-mach Dump after performing the machine dependent reorganization pass, if that pass exists. -fdump-rtl-modesw Dump after removing redundant mode switches. -fdump-rtl-rnreg Dump after register renumbering. -fdump-rtl-outofcfglayout Dump after converting from cfglayout mode. -fdump-rtl-peephole2 Dump after the peephole pass. -fdump-rtl-postreload Dump after post-reload optimizations. -fdump-rtl-proandepilogue Dump after generating the function prologues and epilogues. -fdump-rtl-sched1 -fdump-rtl-sched2 -fdump-rtl-sched1 and -fdump-rtl-sched2 enable dumping after the basic block scheduling passes. -fdump-rtl-ree Dump after sign/zero extension elimination. -fdump-rtl-seqabstr Dump after common sequence discovery. -fdump-rtl-shorten Dump after shortening branches. -fdump-rtl-sibling Dump after sibling call optimizations. -fdump-rtl-split1 -fdump-rtl-split2 -fdump-rtl-split3 -fdump-rtl-split4 -fdump-rtl-split5 These options enable dumping after five rounds of instruction splitting. -fdump-rtl-sms Dump after modulo scheduling. This pass is only run on some architectures. -fdump-rtl-stack Dump after conversion from GCC's \"flat register file\" registers to the x87's stack- like registers. This pass is only run on x86 variants. -fdump-rtl-subreg1 -fdump-rtl-subreg2 -fdump-rtl-subreg1 and -fdump-rtl-subreg2 enable dumping after the two subreg expansion passes. -fdump-rtl-unshare Dump after all rtl has been unshared. -fdump-rtl-vartrack Dump after variable tracking. -fdump-rtl-vregs Dump after converting virtual registers to hard registers. -fdump-rtl-web Dump after live range splitting. -fdump-rtl-regclass -fdump-rtl-subregsofmodeinit -fdump-rtl-subregsofmodefinish -fdump-rtl-dfinit -fdump-rtl-dfinish These dumps are defined but always produce empty files. -da -fdump-rtl-all Produce all the dumps listed above. -dA Annotate the assembler output with miscellaneous debugging information. -dD Dump all macro definitions, at the end of preprocessing, in addition to normal output. -dH Produce a core dump whenever an error occurs. -dp Annotate the assembler output with a comment indicating which pattern and alternative is used. The length and cost of each instruction are also printed. -dP Dump the RTL in the assembler output as a comment before each instruction. Also turns on -dp annotation. -dx Just generate RTL for a function instead of compiling it. Usually used with -fdump-rtl-expand."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dump debugging information generated during the debug generation phase."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dump debugging information generated during the early debug generation phase."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When doing debugging dumps, suppress address output. This makes it more feasible to use diff on debugging dumps for compiler invocations with different compiler binaries and/or different text / bss / data / heap / stack / dso start locations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Collect and dump debug information into a temporary file if an internal compiler error (ICE) occurs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When doing debugging dumps, suppress instruction numbers and address output. This makes it more feasible to use diff on debugging dumps for compiler invocations with different options, in particular with and without -g."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When doing debugging dumps (see -d option above), suppress instruction numbers for the links to the previous and next instructions in a sequence."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Control the dumping at various stages of inter-procedural analysis language tree to a file. The file name is generated by appending a switch specific suffix to the source file name, and the file is created in the same directory as the output file. The following dumps are possible: all Enables all inter-procedural analysis dumps. cgraph Dumps information about call-graph optimization, unused function removal, and inlining decisions. inline Dump after function inlining. Additionally, the options -optimized, -missed, -note, and -all can be provided, with the same meaning as for -fopt-info, defaulting to -optimized. For example, -fdump-ipa-inline-optimized-missed will emit information on callsites that were inlined, along with callsites that were not inlined. By default, the dump will contain messages about successful optimizations (equivalent to -optimized) together with low-level details about the analysis."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dump language-specific information. The file name is made by appending .lang to the source file name."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Control the dumping of language-specific information. The options and filename portions behave as described in the -fdump-tree option. The following switch values are accepted: all Enable all language-specific dumps. class Dump class hierarchy information. Virtual table information is emitted unless 'slim' is specified. This option is applicable to C++ only. module Dump module information. Options lineno (locations), graph (reachability), blocks (clusters), uid (serialization), alias (mergeable), asmname (Elrond), eh (mapper) &"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print on stderr the list of optimization passes that are turned on and off by the current command-line options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable and control dumping of pass statistics in a separate file. The file name is generated by appending a suffix ending in .statistics to the source file name, and the file is created in the same directory as the output file. If the -option form is used, -stats causes counters to be summed over the whole compilation unit while -details dumps every event as the passes generate them. The default with no option is to sum counters for each function compiled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Control the dumping at various stages of processing the intermediate language tree to a file. If the -options form is used, options is a list of - separated options which control the details of the dump. Not all options are applicable to all dumps; those that are not meaningful are ignored. The following options are available address Print the address of each node. Usually this is not meaningful as it changes according to the environment and source file. Its primary use is for tying up a dump file with a debug environment. asmname If \"DECLASSEMBLERNAME\" has been set for a given decl, use that in the dump instead of \"DECLNAME\". Its primary use is ease of use working backward from mangled names in the assembly file. slim When dumping front-end intermediate representations, inhibit dumping of members of a scope or body of a function merely because that scope has been reached. Only dump such items when they are directly reachable by some other path. When dumping pretty-printed trees, this option inhibits dumping the bodies of control structures. When dumping RTL, print the RTL in slim (condensed) form instead of the default LISP- like representation. raw Print a raw representation of the tree. By default, trees are pretty-printed into a C-like representation. details Enable more detailed dumps (not honored by every dump option). Also include information from the optimization passes. stats Enable dumping various statistics about the pass (not honored by every dump option). blocks Enable showing basic block boundaries (disabled in raw dumps). graph For each of the other indicated dump files (-fdump-rtl-pass), dump a representation of the control flow graph suitable for viewing with GraphViz to file.passid.pass.dot. Each function in the file is pretty-printed as a subgraph, so that GraphViz can render them all in a single plot. This option currently only works for RTL dumps, and the RTL is always dumped in slim form. vops Enable showing virtual operands for every statement. lineno Enable showing line numbers for statements. uid Enable showing the unique ID (\"DECLUID\") for each variable. verbose Enable showing the tree dump for each statement. eh Enable showing the EH region number holding each statement. scev Enable showing scalar evolution analysis details. optimized Enable showing optimization information (only available in certain passes). missed Enable showing missed optimization information (only available in certain passes). note Enable other detailed optimization information (only available in certain passes). all Turn on all options, except raw, slim, verbose and lineno. optall Turn on all optimization options, i.e., optimized, missed, and note. To determine what tree dumps are available or find the dump for a pass of interest follow the steps below. 1. Invoke GCC with -fdump-passes and in the stderr output look for a code that corresponds to the pass you are interested in. For example, the codes \"tree-evrp\", \"tree-vrp1\", and \"tree-vrp2\" correspond to the three Value Range Propagation passes. The number at the end distinguishes distinct invocations of the same pass. 2. To enable the creation of the dump file, append the pass code to the -fdump- option prefix and invoke GCC with it. For example, to enable the dump from the Early Value Range Propagation pass, invoke GCC with the -fdump-tree-evrp option. Optionally, you may specify the name of the dump file. If you don't specify one, GCC creates as described below. 3. Find the pass dump in a file whose name is composed of three components separated by a period: the name of the source file GCC was invoked to compile, a numeric suffix indicating the pass number followed by the letter t for tree passes (and the letter r for RTL passes), and finally the pass code. For example, the Early VRP pass dump might be in a file named myfile.c.038t.evrp in the current working directory. Note that the numeric codes are not stable and may change from one version of GCC to another."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Controls optimization dumps from various optimization passes. If the -options form is used, options is a list of - separated option keywords to select the dump details and optimizations. The options can be divided into three groups: 1. options describing what kinds of messages should be emitted, 2. options describing the verbosity of the dump, and 3. options describing which optimizations should be included. The options from each group can be freely mixed as they are non-overlapping. However, in case of any conflicts, the later options override the earlier options on the command line. The following options control which kinds of messages should be emitted: optimized Print information when an optimization is successfully applied. It is up to a pass to decide which information is relevant. For example, the vectorizer passes print the source location of loops which are successfully vectorized. missed Print information about missed optimizations. Individual passes control which information to include in the output. note Print verbose information about optimizations, such as certain transformations, more detailed messages about decisions etc. all Print detailed optimization information. This includes optimized, missed, and note. The following option controls the dump verbosity: internals By default, only \"high-level\" messages are emitted. This option enables additional, more detailed, messages, which are likely to only be of interest to GCC developers. One or more of the following option keywords can be used to describe a group of optimizations: ipa Enable dumps from all interprocedural optimizations. loop Enable dumps from all loop optimizations. inline Enable dumps from all inlining optimizations. omp Enable dumps from all OMP (Offloading and Multi Processing) optimizations. vec Enable dumps from all vectorization optimizations. optall Enable dumps from all optimizations. This is a superset of the optimization groups listed above. If options is omitted, it defaults to optimized-optall, which means to dump messages about successful optimizations from all the passes, omitting messages that are treated as \"internals\". If the filename is provided, then the dumps from all the applicable optimizations are concatenated into the filename. Otherwise the dump is output onto stderr. Though multiple -fopt-info options are accepted, only one of them can include a filename. If other filenames are provided then all but the first such option are ignored. Note that the output filename is overwritten in case of multiple translation units. If a combined output from multiple translation units is desired, stderr should be used instead. In the following example, the optimization info is output to stderr: gcc -O3 -fopt-info This example: gcc -O3 -fopt-info-missed=missed.all outputs missed optimization report from all the passes into missed.all, and this one: gcc -O2 -ftree-vectorize -fopt-info-vec-missed prints information about missed optimization opportunities from vectorization passes on stderr. Note that -fopt-info-vec-missed is equivalent to -fopt-info-missed-vec. The order of the optimization group names and message types listed after -fopt-info does not matter. As another example, gcc -O3 -fopt-info-inline-optimized-missed=inline.txt outputs information about missed optimizations as well as optimized locations from all the inlining passes into inline.txt. Finally, consider: gcc -fopt-info-vec-missed=vec.miss -fopt-info-loop-optimized=loop.opt Here the two output filenames vec.miss and loop.opt are in conflict since only one output file is allowed. In this case, only the first option takes effect and the subsequent options are ignored. Thus only vec.miss is produced which contains dumps from the vectorizer about missed opportunities."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Write a SRCFILE.opt-record.json.gz file detailing what optimizations were performed, for those optimizations that support -fopt-info. This option is experimental and the format of the data within the compressed JSON file is subject to change. It is roughly equivalent to a machine-readable version of -fopt-info-all, as a collection of messages with source file, line number and column number, with the following additional data for each message: * the execution count of the code being optimized, along with metadata about whether this was from actual profile data, or just an estimate, allowing consumers to prioritize messages by code hotness, * the function name of the code being optimized, where applicable, * the \"inlining chain\" for the code being optimized, so that when a function is inlined into several different places (which might themselves be inlined), the reader can distinguish between the copies, * objects identifying those parts of the message that refer to expressions, statements or symbol-table nodes, which of these categories they are, and, when available, their source code location, * the GCC pass that emitted the message, and * the location in GCC's own code from which the message was emitted Additionally, some messages are logically nested within other messages, reflecting implementation details of the optimization passes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On targets that use instruction scheduling, this option controls the amount of debugging output the scheduler prints to the dump files. For n greater than zero, -fsched-verbose outputs the same information as -fdump-rtl-sched1 and -fdump-rtl-sched2. For n greater than one, it also output basic block probabilities, detailed ready list information and unit/insn info. For n greater than two, it includes RTL at abort point, control-flow and regions info. And for n over four, -fsched-verbose also includes dependence info."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This is a set of options that are used to explicitly disable/enable optimization passes. These options are intended for use for debugging GCC. Compiler users should use regular options for enabling/disabling passes instead. -fdisable-ipa-pass Disable IPA pass pass. pass is the pass name. If the same pass is statically invoked in the compiler multiple times, the pass name should be appended with a sequential number starting from 1. -fdisable-rtl-pass -fdisable-rtl-pass=range-list Disable RTL pass pass. pass is the pass name. If the same pass is statically invoked in the compiler multiple times, the pass name should be appended with a sequential number starting from 1. range-list is a comma-separated list of function ranges or assembler names. Each range is a number pair separated by a colon. The range is inclusive in both ends. If the range is trivial, the number pair can be simplified as a single number. If the function's call graph node's uid falls within one of the specified ranges, the pass is disabled for that function. The uid is shown in the function header of a dump file, and the pass names can be dumped by using option -fdump-passes. -fdisable-tree-pass -fdisable-tree-pass=range-list Disable tree pass pass. See -fdisable-rtl for the description of option arguments. -fenable-ipa-pass Enable IPA pass pass. pass is the pass name. If the same pass is statically invoked in the compiler multiple times, the pass name should be appended with a sequential number starting from 1. -fenable-rtl-pass -fenable-rtl-pass=range-list Enable RTL pass pass. See -fdisable-rtl for option argument description and examples. -fenable-tree-pass -fenable-tree-pass=range-list Enable tree pass pass. See -fdisable-rtl for the description of option arguments. Here are some examples showing uses of these options. # disable ccp1 for all functions -fdisable-tree-ccp1 # disable complete unroll for function whose cgraph node uid is 1 -fenable-tree-cunroll=1 # disable gcse2 for functions at the following ranges [1,1], # [300,400], and [400,1000] # disable gcse2 for functions foo and foo2 -fdisable-rtl-gcse2=foo,foo2 # disable early inlining -fdisable-tree-einline # disable ipa inlining -fdisable-ipa-inline # enable tree full unroll -fenable-tree-unroll"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable internal consistency checking. The default depends on the compiler configuration. -fchecking=2 enables further internal consistency checking that might affect code generation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option provides a seed that GCC uses in place of random numbers in generating certain symbol names that have to be different in every compiled file. It is also used to place unique stamps in coverage data files and the object files that produce them. You can use the -frandom-seed option to produce reproducibly identical object files. The string can either be a number (decimal, octal or hex) or an arbitrary string (in which case it's converted to a number by computing CRC32). The string should be different for every file you compile."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Store the usual \"temporary\" intermediate files permanently; name them as auxiliary output files, as specified described under -dumpbase and -dumpdir. When used in combination with the -x command-line option, -save-temps is sensible enough to avoid overwriting an input source file with the same extension as an intermediate file. The corresponding intermediate file may be obtained by renaming the source file before using -save-temps."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Equivalent to -save-temps -dumpdir ./."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Equivalent to -save-temps -dumpdir outdir/, where outdir/ is the directory of the output file specified after the -o option, including any directory separators. If the -o option is not used, the -save-temps=obj switch behaves like -save-temps=cwd."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Report the CPU time taken by each subprocess in the compilation sequence. For C source files, this is the compiler proper and assembler (plus the linker if linking is done). Without the specification of an output file, the output looks like this: # cc1 0.12 0.01 # as 0.00 0.01 The first number on each line is the \"user time\", that is time spent executing the program itself. The second number is \"system time\", time spent executing operating system routines on behalf of the program. Both numbers are in seconds. With the specification of an output file, the output is appended to the named file, and it looks like this: 0.12 0.01 cc1 <options> 0.00 0.01 as <options> The \"user time\" and the \"system time\" are moved before the program name, and the options passed to the program are displayed, so that one can later tell what file was being compiled, and with which options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dump the final internal representation (RTL) to file. If the optional argument is omitted (or if file is \".\"), the name of the dump file is determined by appending \".gkd\" to the dump base name, see -dumpbase."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If no error occurs during compilation, run the compiler a second time, adding opts and -fcompare-debug-second to the arguments passed to the second compilation. Dump the final internal representation in both compilations, and print an error if they differ. If the equal sign is omitted, the default -gtoggle is used. The environment variable GCCCOMPAREDEBUG, if defined, non-empty and nonzero, implicitly enables -fcompare-debug. If GCCCOMPAREDEBUG is defined to a string starting with a dash, then it is used for opts, otherwise the default -gtoggle is used. -fcompare-debug=, with the equal sign but without opts, is equivalent to -fno-compare-debug, which disables the dumping of the final representation and the second compilation, preventing even GCCCOMPAREDEBUG from taking effect. To verify full coverage during -fcompare-debug testing, set GCCCOMPAREDEBUG to say -fcompare-debug-not-overridden, which GCC rejects as an invalid option in any actual compilation (rather than preprocessing, assembly or linking). To get just a warning, setting GCCCOMPAREDEBUG to -w%n-fcompare-debug not overridden will do."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is implicitly passed to the compiler for the second compilation requested by -fcompare-debug, along with options to silence warnings, and omitting other options that would cause the compiler to produce output to files or to standard output as a side effect. Dump files and preserved temporary files are renamed so as to contain the \".gk\" additional extension during the second compilation, to avoid overwriting those generated by the first. When this option is passed to the compiler driver, it causes the first compilation to be skipped, which makes it useful for little other than debugging the compiler proper."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Turn off generation of debug info, if leaving out this option generates it, or turn it on at level 2 otherwise. The position of this argument in the command line does not matter; it takes effect after all other options are processed, and it does so only once, no matter how many times it is given. This is mainly intended to be used with -fcompare-debug."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Toggle -fvar-tracking-assignments, in the same way that -gtoggle toggles -g."
        },
        {
            "flag": "-Q",
            "long": null,
            "arg": null,
            "description": "statistics about each pass when it finishes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Makes the compiler print some statistics about the time consumed by each pass when it finishes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Record the time consumed by infrastructure parts separately for each pass."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Control the verbosity of the dump file for the integrated register allocator. The default value is 5. If the value n is greater or equal to 10, the dump output is sent to stderr using the same format as n minus 10."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Prints a report with internal details on the workings of the link-time optimizer. The contents of this report vary from version to version. It is meant to be useful to GCC developers when processing object files in LTO mode (via -flto). Disabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Like -flto-report, but only print for the WPA phase of link-time optimization."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Makes the compiler print some statistics about permanent memory allocation when it finishes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Makes the compiler print some statistics about permanent memory allocation for the WPA phase only."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Makes the compiler print some statistics about permanent memory allocation before or after interprocedural optimization."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option enables multilib-aware \"TFLAGS\" to be used to build target libraries with options different from those the compiler is configured to use by default, through the use of specs Like \"TFLAGS\", this allows the target libraries to be built for portable baseline environments, while the compiler defaults to more demanding ones. That's useful because users can easily override the defaults the compiler is configured to use to build their own programs, if the defaults are not ideal for their target environment, whereas rebuilding the runtime libraries is usually not as easy or desirable. Unlike \"TFLAGS\", the use of specs enables different flags to be selected for different multilibs. The way to accomplish that is to build with make TFLAGS=-fmultiflags, after configuring --with-specs=%{fmultiflags:...}. This option is discarded by the driver once it's done processing driver self spec. It is also useful to check that \"TFLAGS\" are being used to build all target libraries, by configuring a non-bootstrap compiler --with-specs='%{!fmultiflags:%emissing TFLAGS}' and building the compiler and target libraries."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Makes the compiler print some statistics about consistency of the (estimated) profile and effect of individual passes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Makes the compiler output stack usage information for the program, on a per-function basis. The filename for the dump is made by appending .su to the auxname. auxname is generated from the name of the output file, if explicitly specified and it is not an executable, otherwise it is the basename of the source file. An entry is made up of three fields: * The name of the function. * A number of bytes. * One or more qualifiers: \"static\", \"dynamic\", \"bounded\". The qualifier \"static\" means that the function manipulates the stack statically: a fixed number of bytes are allocated for the frame on function entry and released on function exit; no stack adjustments are otherwise made in the function. The second field is this fixed number of bytes. The qualifier \"dynamic\" means that the function manipulates the stack dynamically: in addition to the static allocation described above, stack adjustments are made in the body of the function, for example to push/pop arguments around function calls. If the qualifier \"bounded\" is also present, the amount of these adjustments is bounded at compile time and the second field is an upper bound of the total amount of stack used by the function. If it is not present, the amount of these adjustments is not bounded at compile time and the second field only represents the bounded part."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit statistics about front-end processing at the end of the compilation. This option is supported only by the C++ front end, and the information is generally only useful to the G++ development team."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print the name and the counter upper bound for all debug counters."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the internal debug counter lower and upper bound. counter-value-list is a comma- separated list of name:lowerbound1-upperbound1 [:lowerbound2-upperbound2...] tuples which sets the name of the counter and list of closed intervals. The lowerbound is optional and is zero initialized if not set. For example, with -fdbg-cnt=dce:2-4:10-11,tailcall:10, dbgcnt(dce) returns true only for second, third, fourth, tenth and eleventh invocation. For dbgcnt(tailcall) true is returned for first 10 invocations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print the full absolute name of the library file library that would be used when linking---and don't do anything else. With this option, GCC does not compile or link anything; it just prints the file name."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print the directory name corresponding to the multilib selected by any other switches present in the command line. This directory is supposed to exist in GCCEXECPREFIX."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print the mapping from multilib directory names to compiler switches that enable them. The directory name is separated from the switches by ;, and each switch starts with an @ instead of the -, without spaces between multiple switches. This is supposed to ease shell processing."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print the path to OS libraries for the selected multilib, relative to some lib subdirectory. If OS libraries are present in the lib subdirectory and no multilibs are used, this is usually just ., if OS libraries are present in libsuffix sibling directories this prints e.g. ../lib64, ../lib or ../lib32, or if OS libraries are present in lib/subdir subdirectories it prints e.g. amd64, sparcv9 or ev6."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print the path to OS libraries for the selected multiarch, relative to some lib subdirectory."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Like -print-file-name, but searches for a program such as cpp."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Same as -print-file-name=libgcc.a. This is useful when you use -nostdlib or -nodefaultlibs but you do want to link with libgcc.a. You can do: gcc -nostdlib <files>... `gcc -print-libgcc-file-name`"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print the name of the configured installation directory and a list of program and library directories gcc searches---and don't do anything else. This is useful when gcc prints the error message installation problem, cannot exec cpp0: No such file or directory. To resolve this you either need to put cpp0 and the other compiler components where gcc expects to find them, or you can set the environment variable GCCEXECPREFIX to the directory where you installed them. Don't forget the trailing /."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print the target sysroot directory that is used during compilation. This is the target sysroot specified either at configure time or using the --sysroot option, possibly with an extra suffix that depends on compilation options. If no target sysroot is specified, the option prints nothing."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print the suffix added to the target sysroot when searching for headers, or give an error if the compiler is not configured with such a suffix---and don't do anything else."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print the compiler's target machine (for example, i686-pc-linux-gnu)---and don't do anything else."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print the compiler version (for example, 3.0, 6.3.0 or 7)---and don't do anything else. This is the compiler version used in filesystem paths and specs. Depending on how the compiler has been configured it can be just a single number (major version), two numbers separated by a dot (major and minor version) or three numbers separated by dots (major, minor and patchlevel version)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print the full compiler version---and don't do anything else. The output is always three numbers separated by dots, major, minor and patchlevel version."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print the compiler's built-in specs---and don't do anything else. (This is used when GCC itself is being built.)"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the specified data model. Permissible values are ilp32 for SysV-like data model where int, long int and pointers are 32 bits, and lp64 for SysV-like data model where int is 32 bits, but long int and pointers are 64 bits. The default depends on the specific target configuration. Note that the LP64 and ILP32 ABIs are not link-compatible; you must compile your entire program with the same ABI, and link with a compatible set of libraries."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate big-endian code. This is the default when GCC is configured for an aarch64be-*-* target."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code which uses only the general-purpose registers. This will prevent the compiler from using floating-point and Advanced SIMD registers but will not impose any restrictions on the assembler."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate little-endian code. This is the default when GCC is configured for an aarch64-*-* but not an aarch64be-*-* target."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the tiny code model. The program and its statically defined symbols must be within 1MB of each other. Programs can be statically or dynamically linked."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the small code model. The program and its statically defined symbols must be within 4GB of each other. Programs can be statically or dynamically linked. This is the default code model."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the large code model. This makes no assumptions about addresses and sizes of sections. Programs can be statically linked only. The -mcmodel=large option is incompatible with -mabi=ilp32, -fpic and -fPIC."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Avoid or allow generating memory accesses that may not be aligned on a natural object boundary as described in the architecture specification."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Omit or keep the frame pointer in leaf functions. The former behavior is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate stack protection code using canary at guard. Supported locations are global for a global canary or sysreg for a canary in an appropriate system register. With the latter choice the options -mstack-protector-guard-reg=reg and -mstack-protector-guard-offset=offset furthermore specify which system register to use as base register for reading the canary, and from what offset from that base register. There is no default register or offset as this is entirely for use within the Linux kernel."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use TLS descriptors as the thread-local storage mechanism for dynamic accesses of TLS variables. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use traditional TLS as the thread-local storage mechanism for dynamic accesses of TLS variables."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify bit size of immediate TLS offsets. Valid values are 12, 24, 32, 48. This option requires binutils 2.26 or newer."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable or disable the workaround for the ARM Cortex-A53 erratum number 835769. This involves inserting a NOP instruction between memory instructions and 64-bit integer multiply-accumulate instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable or disable the workaround for the ARM Cortex-A53 erratum number 843419. This erratum workaround is made at link time and this will only pass the corresponding flag to the linker."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable or disable the reciprocal square root approximation. This option only has an effect if -ffast-math or -funsafe-math-optimizations is used as well. Enabling this reduces precision of reciprocal square root results to about 16 bits for single precision and to 32 bits for double precision."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable or disable the square root approximation. This option only has an effect if -ffast-math or -funsafe-math-optimizations is used as well. Enabling this reduces precision of square root results to about 16 bits for single precision and to 32 bits for double precision. If enabled, it implies -mlow-precision-recip-sqrt."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable or disable the division approximation. This option only has an effect if -ffast-math or -funsafe-math-optimizations is used as well. Enabling this reduces precision of division results to about 16 bits for single precision and to 32 bits for double precision."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable or disable generation of additional code to track speculative execution through conditional branches. The tracking state can then be used by the compiler when expanding calls to \"builtinspeculationsafecopy\" to permit a more efficient code sequence to be generated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable or disable calls to out-of-line helpers to implement atomic operations. These helpers will, at runtime, determine if the LSE instructions from ARMv8.1-A can be used; if not, they will use the load/store-exclusive instructions that are present in the base ARMv8.0 ISA. This option is only applicable when compiling for the base ARMv8.0 instruction set. If using a later revision, e.g. -march=armv8.1-a or -march=armv8-a+lse, the ARMv8.1-Atomics instructions will be used directly. The same applies when using -mcpu= when the selected cpu supports the lse feature. This option is on by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the name of the target architecture and, optionally, one or more feature modifiers. This option has the form -march=arch{+[no]feature}*. The table below summarizes the permissible values for arch and the features that they enable by default: arch value : Architecture : Includes by default armv8-a : Armv8-A : +fp, +simd armv8.1-a : Armv8.1-A : armv8-a, +crc, +lse, +rdma armv8.2-a : Armv8.2-A : armv8.1-a armv8.3-a : Armv8.3-A : armv8.2-a, +pauth armv8.4-a : Armv8.4-A : armv8.3-a, +flagm, +fp16fml, +dotprod armv8.5-a : Armv8.5-A : armv8.4-a, +sb, +ssbs, +predres armv8.6-a : Armv8.6-A : armv8.5-a, +bf16, +i8mm armv8.7-a : Armv8.7-A : armv8.6-a, +ls64 armv8.8-a : Armv8.8-a : armv8.7-a, +mops armv9-a : Armv9-A : armv8.5-a, +sve, +sve2 armv9.1-a : Armv9.1-A : armv9-a, +bf16, +i8mm armv9.2-a : Armv9.2-A : armv9.1-a, +ls64 armv9.3-a : Armv9.3-A : armv9.2-a, +mops armv8-r : Armv8-R : armv8-r The value native is available on native AArch64 GNU/Linux and causes the compiler to pick the architecture of the host system. This option has no effect if the compiler is unable to recognize the architecture of the host system, The permissible values for feature are listed in the sub-section on aarch64-feature-modifiers,,-march and -mcpu Feature Modifiers. Where conflicting feature modifiers are specified, the right-most feature is used. GCC uses name to determine what kind of instructions it can emit when generating assembly code. If -march is specified without either of -mtune or -mcpu also being specified, the code is tuned to perform well across a range of target processors implementing the target architecture."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the name of the target processor for which GCC should tune the performance of the code. Permissible values for this option are: generic, cortex-a35, cortex-a53, cortex-a55, cortex-a57, cortex-a72, cortex-a73, cortex-a75, cortex-a76, cortex-a76ae, cortex-a77, cortex-a65, cortex-a65ae, cortex-a34, cortex-a78, cortex-a78ae, cortex-a78c, ares, exynos-m1, emag, falkor, neoverse-512tvb, neoverse-e1, neoverse-n1, neoverse-n2, neoverse-v1, neoverse-v2, qdf24xx, saphira, phecda, xgene1, vulcan, octeontx, octeontx81, octeontx83, octeontx2, octeontx2t98, octeontx2t96 octeontx2t93, octeontx2f95, octeontx2f95n, octeontx2f95mm, a64fx, thunderx, thunderxt88, thunderxt88p1, thunderxt81, tsv110, thunderxt83, thunderx2t99, thunderx3t110, zeus, cortex-a57.cortex-a53, cortex-a72.cortex-a53, cortex-a73.cortex-a35, cortex-a73.cortex-a53, cortex-a75.cortex-a55, cortex-a76.cortex-a55, cortex-r82, cortex-x1, cortex-x1c, cortex-x2, cortex-x3, cortex-a510, cortex-a710, cortex-a715, ampere1, ampere1a, cobalt-100 and native. The values cortex-a57.cortex-a53, cortex-a72.cortex-a53, cortex-a73.cortex-a35, cortex-a73.cortex-a53, cortex-a75.cortex-a55, cortex-a76.cortex-a55 specify that GCC should tune for a big.LITTLE system. The value neoverse-512tvb specifies that GCC should tune for Neoverse cores that (a) implement SVE and (b) have a total vector bandwidth of 512 bits per cycle. In other words, the option tells GCC to tune for Neoverse cores that can execute 4 128-bit Advanced SIMD arithmetic instructions a cycle and that can execute an equivalent number of SVE arithmetic instructions per cycle (2 for 256-bit SVE, 4 for 128-bit SVE). This is more general than tuning for a specific core like Neoverse V1 but is more specific than the default tuning described below. Additionally on native AArch64 GNU/Linux systems the value native tunes performance to the host system. This option has no effect if the compiler is unable to recognize the processor of the host system. Where none of -mtune=, -mcpu= or -march= are specified, the code is tuned to perform well across a range of target processors. This option cannot be suffixed by feature modifiers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the name of the target processor, optionally suffixed by one or more feature modifiers. This option has the form -mcpu=cpu{+[no]feature}*, where the permissible values for cpu are the same as those available for -mtune. The permissible values for feature are documented in the sub-section on aarch64-feature-modifiers,,-march and -mcpu Feature Modifiers. Where conflicting feature modifiers are specified, the right-most feature is used. GCC uses name to determine what kind of instructions it can emit when generating assembly code (as if by -march) and to determine the target processor for which to tune for performance (as if by -mtune). Where this option is used in conjunction with -march or -mtune, those options take precedence over the appropriate part of this option. -mcpu=neoverse-512tvb is special in that it does not refer to a specific core, but instead refers to all Neoverse cores that (a) implement SVE and (b) have a total vector bandwidth of 512 bits a cycle. Unless overridden by -march, -mcpu=neoverse-512tvb generates code that can run on a Neoverse V1 core, since Neoverse V1 is the first Neoverse core with these properties. Unless overridden by -mtune, -mcpu=neoverse-512tvb tunes code in the same way as for -mtune=neoverse-512tvb."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Override tuning decisions made by the back-end in response to a -mtune= switch. The syntax, semantics, and accepted values for string in this option are not guaranteed to be consistent across releases. This option is only intended to be useful when developing GCC."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable verbose cost model dumping in the debug dump files. This option is provided for use in debugging the compiler."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable or disable PC-relative literal loads. With this option literal pools are accessed using a single instruction and emitted after each function. This limits the maximum size of functions to 1MB. This is enabled by default for -mcmodel=tiny."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select the function scope on which return address signing will be applied. Permissible values are none, which disables return address signing, non-leaf, which enables pointer signing for functions which are not leaf functions, and all, which enables pointer signing for all functions. The default value is none. This option has been deprecated by -mbranch-protection."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select the branch protection features to use. none is the default and turns off all types of branch protection. standard turns on all types of branch protection features. If a feature has additional tuning options, then standard sets it to its standard level. pac-ret[+leaf] turns on return address signing to its standard level: signing functions that save the return address to memory (non-leaf functions will practically always do this) using the a-key. The optional argument leaf can be used to extend the signing to include leaf functions. The optional argument b-key can be used to sign the functions with the B-key instead of the A-key. bti turns on branch target identification mechanism."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable compiler hardening against straight line speculation (SLS). opts is a comma- separated list of the following options: retbr blr In addition, -mharden-sls=all enables all SLS hardening while -mharden-sls=none disables all SLS hardening."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the number of bits in an SVE vector register. This option only has an effect when SVE is enabled. GCC supports two forms of SVE code generation: \"vector-length agnostic\" output that works with any size of vector register and \"vector-length specific\" output that allows GCC to make assumptions about the vector length when it is useful for optimization reasons. The possible values of bits are: scalable, 128, 256, 512, 1024 and 2048. Specifying scalable selects vector-length agnostic output. At present -msve-vector-bits=128 also generates vector-length agnostic output for big-endian targets. All other values generate vector- length specific code. The behavior of these values may change in future releases and no value except scalable should be relied on for producing code that is portable across different hardware SVE vector lengths. The default is -msve-vector-bits=scalable, which produces vector-length agnostic code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Feature modifiers used with -march and -mcpu can be any of the following and their inverses nofeature: crc Enable CRC extension. This is on by default for -march=armv8.1-a."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't allocate any register in the range \"r32\"...\"r63\". That allows code to run on hardware variants that lack these registers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Preferentially allocate registers that allow short instruction generation. This can result in increased instruction count, so this may either reduce or increase overall code size."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the cost of branches to roughly num \"simple\" instructions. This cost is only a heuristic and is not guaranteed to produce consistent results across releases."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the generation of conditional moves."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit num NOPs before every other generated instruction."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "For single-precision floating-point comparisons, emit an \"fsub\" instruction and test the flags. This is faster than a software comparison, but can get incorrect results in the presence of NaNs, or when two different small numbers are compared such that their difference is calculated as zero. The default is -msoft-cmpsf, which uses slower, but IEEE-compliant, software comparisons."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the offset between the top of the stack and the stack pointer. E.g., a value of 8 means that the eight bytes in the range \"sp+0...sp+7\" can be used by leaf functions without stack allocation. Values other than 8 or 16 are untested and unlikely to work. Note also that this option changes the ABI; compiling a program with a different stack offset than the libraries have been compiled with generally does not work. This option can be useful if you want to evaluate if a different stack offset would give you better code, but to actually use a different stack offset to build working programs, it is recommended to configure the toolchain with the appropriate --with-stack-offset=num option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Make the scheduler assume that the rounding mode has been set to truncating. The default is -mround-nearest."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If not otherwise specified by an attribute, assume all calls might be beyond the offset range of the \"b\" / \"bl\" instructions, and therefore load the function address into a register before performing a (otherwise direct) call. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If not otherwise specified by an attribute, assume all direct calls are in the range of the \"b\" / \"bl\" instructions, so use these instructions for direct calls. The default is -mlong-calls."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume addresses can be loaded as 16-bit unsigned values. This does not apply to function addresses for which -mlong-calls semantics are in effect."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the prevailing mode of the floating-point unit. This determines the floating-point mode that is provided and expected at function call and return time. Making this mode match the mode you predominantly need at function start can make your programs smaller and faster by avoiding unnecessary mode switches. mode can be set to one the following values: caller Any mode at function entry is valid, and retained or restored when the function returns, and when it calls other functions. This mode is useful for compiling libraries or other compilation units you might want to incorporate into different programs with different prevailing FPU modes, and the convenience of being able to use a single object file outweighs the size and speed overhead for any extra mode switching that might be needed, compared with what would be needed with a more specific choice of prevailing FPU mode. truncate This is the mode used for floating-point calculations with truncating (i.e. round towards zero) rounding mode. That includes conversion from floating point to integer. round-nearest This is the mode used for floating-point calculations with round-to-nearest-or-even rounding mode. int This is the mode used to perform integer calculations in the FPU, e.g. integer multiply, or integer multiply-and-accumulate. The default is -mfp-mode=caller"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Code generation tweaks that disable, respectively, splitting of 32-bit loads, generation of post-increment addresses, and generation of post-modify addresses. The defaults are msplit-lohi, -mpost-inc, and -mpost-modify."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Change the preferred SIMD mode to SImode. The default is -mvect-double, which uses DImode as preferred SIMD mode."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The maximum alignment for SIMD vector mode types. num may be 4 or 8. The default is 8. Note that this is an ABI change, even though many library function interfaces are unaffected if they don't use SIMD vector modes in places that affect size and/or alignment of relevant types."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Split vector moves into single word moves before reload. In theory this can give better register allocation, but so far the reverse seems to be generally the case."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify a register to hold the constant -1, which makes loading small negative constants and certain bitmasks faster. Allowable values for reg are r43 and r63, which specify use of that register as a fixed register, and none, which means that no register is used for this purpose. The default is -m1reg-none. AMD GCN Options These options are defined specifically for the AMD GCN port."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set architecture type or tuning for gpu. Supported values for gpu are fiji Compile for GCN3 Fiji devices (gfx803). gfx900 Compile for GCN5 Vega 10 devices (gfx900). gfx906 Compile for GCN5 Vega 20 devices (gfx906). gfx908 Compile for CDNA1 Instinct MI100 series devices (gfx908). gfx90a Compile for CDNA2 Instinct MI200 series devices (gfx90a)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Compile binaries suitable for devices with the SRAM-ECC feature enabled, disabled, or either mode. This feature can be enabled per-process on some devices. The compiled code must match the device mode. The default is any, for devices that support it."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify how many bytes of stack space will be requested for each GPU thread (wave-front). Beware that there may be many threads and limited memory available. The size of the stack allocation may also have an impact on run-time performance. The default is 32KB when using OpenACC or OpenMP, and 1MB otherwise."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Compile binaries suitable for devices with the XNACK feature enabled. Some devices always require XNACK and some allow the user to configure XNACK. The compiled code must match the device mode. The default is -mno-xnack. At present this option is a placeholder for support that is not yet implemented. ARC Options The following options control the architecture variant for which code is being compiled:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate instructions supported by barrel shifter. This is the default unless -mcpu=ARC601 or -mcpu=ARCEM is in effect."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force to call a function using jlis instruction. This option is valid only for ARCv2 architecture."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set architecture type, register usage, and instruction scheduling parameters for cpu. There are also shortcut alias options available for backward compatibility and convenience. Supported values for cpu are arc600 Compile for ARC600. Aliases: -mA6, -mARC600. arc601 Compile for ARC601. Alias: -mARC601. arc700 Compile for ARC700. Aliases: -mA7, -mARC700. This is the default when configured with --with-cpu=arc700. arcem Compile for ARC EM. archs Compile for ARC HS. em Compile for ARC EM CPU with no hardware extensions. em4 Compile for ARC EM4 CPU. em4dmips Compile for ARC EM4 DMIPS CPU. em4fpus Compile for ARC EM4 DMIPS CPU with the single-precision floating-point extension. em4fpuda Compile for ARC EM4 DMIPS CPU with single-precision floating-point and double assist instructions. hs Compile for ARC HS CPU with no hardware extensions except the atomic instructions. hs34 Compile for ARC HS34 CPU. hs38 Compile for ARC HS38 CPU. hs38linux Compile for ARC HS38 CPU with all hardware extensions on. hs4x Compile for ARC HS4x CPU. hs4xd Compile for ARC HS4xD CPU. hs4xrel31 Compile for ARC HS4x CPU release 3.10a. arc600norm Compile for ARC 600 CPU with \"norm\" instructions enabled. arc600mul32x16 Compile for ARC 600 CPU with \"norm\" and 32x16-bit multiply instructions enabled. arc600mul64 Compile for ARC 600 CPU with \"norm\" and \"mul64\"-family instructions enabled. arc601norm Compile for ARC 601 CPU with \"norm\" instructions enabled. arc601mul32x16 Compile for ARC 601 CPU with \"norm\" and 32x16-bit multiply instructions enabled. arc601mul64 Compile for ARC 601 CPU with \"norm\" and \"mul64\"-family instructions enabled. nps400 Compile for ARC 700 on NPS400 chip. emmini Compile for ARC EM minimalist configuration featuring reduced register set."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate double-precision FPX instructions, tuned for the compact implementation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate double-precision FPX instructions, tuned for the fast implementation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable \"lr\" and \"sr\" instructions from using FPX extension aux registers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate extended arithmetic instructions. Currently only \"divaw\", \"adds\", \"subs\", and \"sat16\" are supported. Only valid for -mcpu=ARC700."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not generate \"mpy\"-family instructions for ARC700. This option is deprecated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate 32x16-bit multiply and multiply-accumulate instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate \"mul64\" and \"mulu64\" instructions. Only valid for -mcpu=ARC600."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate \"norm\" instructions. This is the default if -mcpu=ARC700 is in effect."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate single-precision FPX instructions, tuned for the compact implementation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate single-precision FPX instructions, tuned for the fast implementation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable generation of ARC SIMD instructions via target-specific builtins. Only valid for -mcpu=ARC700."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option ignored; it is provided for compatibility purposes only. Software floating- point code is emitted by default, and this default can overridden by FPX options; -mspfp, -mspfp-compact, or -mspfp-fast for single precision, and -mdpfp, -mdpfp-compact, or -mdpfp-fast for double precision."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate \"swap\" instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This enables use of the locked load/store conditional extension to implement atomic memory built-in functions. Not available for ARC 6xx or ARC EM cores."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable \"div\" and \"rem\" instructions for ARCv2 cores."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable code density instructions for ARC EM. This option is on by default for ARC HS."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable double load/store operations for ARC HS cores."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify thread pointer register number."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Compile ARCv2 code with a multiplier design option. You can specify the option using either a string or numeric value for multo. wlh1 is the default value. The recognized values are: 0 none No multiplier available. 1 w 16x16 multiplier, fully pipelined. The following instructions are enabled: \"mpyw\" and \"mpyuw\". 2 wlh1 32x32 multiplier, fully pipelined (1 stage). The following instructions are additionally enabled: \"mpy\", \"mpyu\", \"mpym\", \"mpymu\", and \"mpys\". 3 wlh2 32x32 multiplier, fully pipelined (2 stages). The following instructions are additionally enabled: \"mpy\", \"mpyu\", \"mpym\", \"mpymu\", and \"mpys\". 4 wlh3 Two 16x16 multipliers, blocking, sequential. The following instructions are additionally enabled: \"mpy\", \"mpyu\", \"mpym\", \"mpymu\", and \"mpys\". 5 wlh4 One 16x16 multiplier, blocking, sequential. The following instructions are additionally enabled: \"mpy\", \"mpyu\", \"mpym\", \"mpymu\", and \"mpys\". 6 wlh5 One 32x4 multiplier, blocking, sequential. The following instructions are additionally enabled: \"mpy\", \"mpyu\", \"mpym\", \"mpymu\", and \"mpys\". 7 plusdmpy ARC HS SIMD support. 8 plusmacd ARC HS SIMD support. 9 plusqmacw ARC HS SIMD support. This option is only available for ARCv2 cores."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enables support for specific floating-point hardware extensions for ARCv2 cores. Supported values for fpu are: fpus Enables support for single-precision floating-point hardware extensions. fpud Enables support for double-precision floating-point hardware extensions. The single- precision floating-point extension is also enabled. Not available for ARC EM. fpuda Enables support for double-precision floating-point hardware extensions using double- precision assist instructions. The single-precision floating-point extension is also enabled. This option is only available for ARC EM. fpudadiv Enables support for double-precision floating-point hardware extensions using double- precision assist instructions. The single-precision floating-point, square-root, and divide extensions are also enabled. This option is only available for ARC EM. fpudafma Enables support for double-precision floating-point hardware extensions using double- precision assist instructions. The single-precision floating-point and fused multiply and add hardware extensions are also enabled. This option is only available for ARC EM. fpudaall Enables support for double-precision floating-point hardware extensions using double- precision assist instructions. All single-precision floating-point hardware extensions are also enabled. This option is only available for ARC EM. fpusdiv Enables support for single-precision floating-point, square-root and divide hardware extensions. fpuddiv Enables support for double-precision floating-point, square-root and divide hardware extensions. This option includes option fpusdiv. Not available for ARC EM. fpusfma Enables support for single-precision floating-point and fused multiply and add hardware extensions. fpudfma Enables support for double-precision floating-point and fused multiply and add hardware extensions. This option includes option fpusfma. Not available for ARC EM. fpusall Enables support for all single-precision floating-point hardware extensions. fpudall Enables support for all single- and double-precision floating-point hardware extensions. Not available for ARC EM."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies general-purposes registers that the processor automatically saves/restores on interrupt entry and exit. register-range is specified as two registers separated by a dash. The register range always starts with \"r0\", the upper limit is \"fp\" register. blink and lpcount are optional. This option is only valid for ARC EM and ARC HS cores."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies the number of registers replicated in second register bank on entry to fast interrupt. Fast interrupts are interrupts with the highest priority level P0. These interrupts save only PC and STATUS32 registers to avoid memory transactions during interrupt entry and exit sequences. Use this option when you are using fast interrupts in an ARC V2 family processor. Permitted values are 4, 8, 16, and 32."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the width of the \"lpcount\" register. Valid values for width are 8, 16, 20, 24, 28 and 32 bits. The default width is fixed to 32 bits. If the width is less than 32, the compiler does not attempt to transform loops in your program to use the zero-delay loop mechanism unless it is known that the \"lpcount\" register can hold the required loop-counter value. Depending on the width specified, the compiler and run-time library might continue to use the loop mechanism for various needs. This option defines macro \"ARCLPCWIDTH\" with the value of width."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option instructs the compiler to generate code for a 16-entry register file. This option defines the \"ARCRF16\" preprocessor macro."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable use of \"bi\" or \"bih\" instructions to implement jump tables. The following options are passed through to the assembler, and also define preprocessor macro symbols."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Passed down to the assembler to enable the DSP Pack A extensions. Also sets the preprocessor symbol \"Xdsppacka\". This option is deprecated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Passed down to the assembler to enable the dual Viterbi butterfly extension. Also sets the preprocessor symbol \"Xdvbf\". This option is deprecated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Passed down to the assembler to enable the locked load/store conditional extension. Also sets the preprocessor symbol \"Xlock\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Passed down to the assembler. Also sets the preprocessor symbol \"Xxmacd16\". This option is deprecated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Passed down to the assembler. Also sets the preprocessor symbol \"Xxmac24\". This option is deprecated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Passed down to the assembler to enable the 64-bit time-stamp counter extension instruction. Also sets the preprocessor symbol \"Xrtsc\". This option is deprecated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Passed down to the assembler to enable the swap byte ordering extension instruction. Also sets the preprocessor symbol \"Xswape\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Passed down to the assembler to enable dual- and single-operand instructions for telephony. Also sets the preprocessor symbol \"Xtelephony\". This option is deprecated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Passed down to the assembler to enable the XY memory extension. Also sets the preprocessor symbol \"Xxy\". The following options control how the assembly code is annotated:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Annotate assembler instructions with estimated addresses."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Explain what alignment considerations lead to the decision to make an instruction short or long. The following options are passed through to the linker:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Passed through to the linker, to specify use of the \"arclinux\" emulation. This option is enabled by default in tool chains built for \"arc-linux-uclibc\" and \"arceb-linux-uclibc\" targets when profiling is not requested."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Passed through to the linker, to specify use of the \"arclinuxprof\" emulation. This option is enabled by default in tool chains built for \"arc-linux-uclibc\" and \"arceb-linux-uclibc\" targets when profiling is requested. The following options control the semantics of generated code:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate calls as register indirect calls, thus providing access to the full 32-bit address range."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't use less than 25-bit addressing range for calls, which is the offset available for an unconditional branch-and-link instruction. Conditional execution of function calls is suppressed, to allow use of the 25-bit range, rather than the 21-bit range with conditional branch-and-link. This is the default for tool chains built for \"arc-linux-uclibc\" and \"arceb-linux-uclibc\" targets."
        },
        {
            "flag": "-G",
            "long": null,
            "arg": null,
            "description": "Put definitions of externally-visible data in a small data section if that data is no bigger than num bytes. The default value of num is 4 for any ARC configuration, or 8 when we have double load/store operations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not generate sdata references. This is the default for tool chains built for \"arc-linux-uclibc\" and \"arceb-linux-uclibc\" targets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use ordinarily cached memory accesses for volatile references. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable cache bypass for volatile references. The following options fine tune code generation:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Does nothing. Preserved for backward compatibility."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the use of pre/post modify with register displacement."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable bbit peephole2."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option disables a target-specific pass in arcreorg to generate compare-and-branch (\"brcc\") instructions. It has no effect on generation of these instructions driven by the combiner pass."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use PC-relative switch case tables to enable case table shortening. This is the default for -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable compact \"casesi\" pattern. This is the default for -Os, and only available for ARCv1 cores. This option is deprecated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable the ARCompact-specific pass to generate conditional execution instructions. Due to delay slot scheduling and interactions between operand numbers, literal sizes, instruction lengths, and the support for conditional execution, the target-independent pass to generate conditional execution is often lacking, so the ARC port has kept a special pass around that tries to find more conditional execution generation opportunities after register allocation, branch shortening, and delay slot scheduling have been done. This pass generally, but not always, improves performance and code size, at the cost of extra compilation time, which is why there is an option to switch it off. If you have a problem with call instructions exceeding their allowable offset range because they are conditionalized, you should consider using -mmedium-calls instead."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable pre-reload use of the \"cbranchsi\" pattern."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Expand \"adddi3\" and \"subdi3\" at RTL generation time into \"add.f\", \"adc\" etc. This option is deprecated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the use of indexed loads. This can be problematic because some optimizers then assume that indexed stores exist, which is not the case."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable Local Register Allocation. This is still experimental for ARC, so by default the compiler uses standard reload (i.e. -mno-lra)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't indicate any priority for target registers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Indicate target register priority for r0..r3 / r12..r15."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Reduce target register priority for r0..r3 / r12..r15."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When optimizing for size (using -Os), prologues and epilogues that have to save or restore a large number of registers are often shortened by using call to a special function in libgcc; this is referred to as a millicode call. As these calls can pose performance issues, and/or cause linking issues when linking in a nonstandard way, this option is provided to turn on or off millicode call generation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option enable the compiler to emit \"enter\" and \"leave\" instructions. These instructions are only valid for CPUs with code-density feature."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Does nothing. Preserved for backward compatibility."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Ths option is deprecated. Enable q instruction alternatives. This is the default for -Os."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Does nothing. Preserved for backward compatibility."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Does nothing. Preserved for backward compatibility."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Fine-tune size optimization with regards to instruction lengths and alignment. The recognized values for level are: 0 No size optimization. This level is deprecated and treated like 1. 1 Short instructions are used opportunistically. 2 In addition, alignment of loops and of code after barriers are dropped. 3 In addition, optional data alignment is dropped, and the option Os is enabled. This defaults to 3 when -Os is in effect. Otherwise, the behavior when this is not set is equivalent to level 1."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set instruction scheduling parameters for cpu, overriding any implied by -mcpu=. Supported values for cpu are ARC600 Tune for ARC600 CPU. ARC601 Tune for ARC601 CPU. ARC700 Tune for ARC700 CPU with standard multiplier block. ARC700-xmac Tune for ARC700 CPU with XMAC block. ARC725D Tune for ARC725D CPU. ARC750D Tune for ARC750D CPU. core3 Tune for ARCv2 core3 type CPU. This option enable usage of \"dbnz\" instruction. release31a Tune for ARC4x release 3.10a."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Cost to assume for a multiply instruction, with 4 being equal to a normal instruction."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Does nothing. Preserved for backward compatibility. The following options are maintained for backward compatibility, but are now deprecated and will be removed in a future release:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Obsolete FPX."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "code is supported by configuring GCC to build \"arceb-elf32\" and \"arceb-linux-uclibc\" targets, for which big endian is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "endian code is supported by configuring GCC to build \"arc-elf32\" and \"arc-linux-uclibc\" targets, for which little endian is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Replaced by -mbarrel-shifter."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Replaced by -mdpfp-compact."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Replaced by -mdpfp-fast."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Replaced by -mdsp-packa."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Replaced by -mea."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Replaced by -mmac-24."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Replaced by -mmac-d16."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Replaced by -mspfp-compact."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Replaced by -mspfp-fast."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Values arc600, arc601, arc700 and arc700-xmac for cpu are replaced by ARC600, ARC601, ARC700 and ARC700-xmac respectively."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Replaced by -mmultcost. ARM Options These -m options are defined for the ARM port:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the specified ABI. Permissible values are: apcs-gnu, atpcs, aapcs, aapcs-linux and iwmmxt."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate a stack frame that is compliant with the ARM Procedure Call Standard for all functions, even if this is not strictly necessary for correct execution of the code. Specifying -fomit-frame-pointer with this option causes the stack frames not to be generated for leaf functions. The default is -mno-apcs-frame. This option is deprecated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This is a synonym for -mapcs-frame and is deprecated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that supports calling between the ARM and Thumb instruction sets. Without this option, on pre-v5 architectures, the two instruction sets cannot be reliably used inside one program. The default is -mno-thumb-interwork, since slightly larger code is generated when -mthumb-interwork is specified. In AAPCS configurations this option is meaningless."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Prevent the reordering of instructions in the function prologue, or the merging of those instruction with the instructions in the function's body. This means that all functions start with a recognizable set of instructions (or in fact one of a choice from a small set of different function prologues), and this information can be used to locate the start of functions inside an executable piece of code. The default is -msched-prolog."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies which floating-point ABI to use. Permissible values are: soft, softfp and hard. Specifying soft causes GCC to generate output containing library calls for floating-point operations. softfp allows the generation of code using hardware floating-point instructions, but still uses the soft-float calling conventions. hard allows generation of floating-point instructions and uses FPU-specific calling conventions. The default depends on the specific target configuration. Note that the hard-float and soft-float ABIs are not link-compatible; you must compile your entire program with the same ABI, and link with a compatible set of libraries."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code which uses only the general-purpose registers. This will prevent the compiler from using floating-point and Advanced SIMD registers but will not impose any restrictions on the assembler."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a processor running in little-endian mode. This is the default for all standard configurations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a processor running in big-endian mode; the default is to compile code for a little-endian processor."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When linking a big-endian image select between BE8 and BE32 formats. The option has no effect for little-endian images and is ignored. The default is dependent on the selected target architecture. For ARMv6 and later architectures the default is BE8, for older architectures the default is BE32. BE32 format has been deprecated by ARM."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This specifies the name of the target ARM architecture. GCC uses this name to determine what kind of instructions it can emit when generating assembly code. This option can be used in conjunction with or instead of the -mcpu= option. Permissible names are: armv4t, armv5t, armv5te, armv6, armv6j, armv6k, armv6kz, armv6t2, armv6z, armv6zk, armv7, armv7-a, armv7ve, armv8-a, armv8.1-a, armv8.2-a, armv8.3-a, armv8.4-a, armv8.5-a, armv8.6-a, armv9-a, armv7-r, armv8-r, armv6-m, armv6s-m, armv7-m, armv7e-m, armv8-m.base, armv8-m.main, armv8.1-m.main, armv9-a, iwmmxt and iwmmxt2. Additionally, the following architectures, which lack support for the Thumb execution state, are recognized but support is deprecated: armv4. Many of the architectures support extensions. These can be added by appending +extension to the architecture name. Extension options are processed in order and capabilities accumulate. An extension will also enable any necessary base extensions upon which it depends. For example, the +crypto extension will always enable the +simd extension. The exception to the additive construction is for extensions that are prefixed with +no...: these extensions disable the specified option and any other extensions that may depend on the presence of that extension. For example, -march=armv7-a+simd+nofp+vfpv4 is equivalent to writing -march=armv7-a+vfpv4 since the +simd option is entirely disabled by the +nofp option that follows it. Most extension names are generically named, but have an effect that is dependent upon the architecture to which it is applied. For example, the +simd option can be applied to both armv7-a and armv8-a architectures, but will enable the original ARMv7-A Advanced SIMD (Neon) extensions for armv7-a and the ARMv8-A variant for armv8-a. The table below lists the supported extensions for each architecture. Architectures not mentioned do not support any extensions. armv5te armv6 armv6j armv6k armv6kz armv6t2 armv6z armv6zk +fp The VFPv2 floating-point instructions. The extension +vfpv2 can be used as an alias for this extension. +nofp Disable the floating-point instructions. armv7 The common subset of the ARMv7-A, ARMv7-R and ARMv7-M architectures. +fp The VFPv3 floating-point instructions, with 16 double-precision registers. The extension +vfpv3-d16 can be used as an alias for this extension. Note that floating-point is not supported by the base ARMv7-M architecture, but is compatible with both the ARMv7-A and ARMv7-R architectures. +nofp Disable the floating-point instructions. armv7-a +mp The multiprocessing extension. +sec The security extension. +fp The VFPv3 floating-point instructions, with 16 double-precision registers. The extension +vfpv3-d16 can be used as an alias for this extension. +simd The Advanced SIMD (Neon) v1 and the VFPv3 floating-point instructions. The extensions +neon and +neon-vfpv3 can be used as aliases for this extension. +vfpv3 The VFPv3 floating-point instructions, with 32 double-precision registers. +vfpv3-d16-fp16 The VFPv3 floating-point instructions, with 16 double-precision registers and the half-precision floating-point conversion operations. +vfpv3-fp16 The VFPv3 floating-point instructions, with 32 double-precision registers and the half-precision floating-point conversion operations. +vfpv4-d16 The VFPv4 floating-point instructions, with 16 double-precision registers. +vfpv4 The VFPv4 floating-point instructions, with 32 double-precision registers. +neon-fp16 The Advanced SIMD (Neon) v1 and the VFPv3 floating-point instructions, with the half-precision floating-point conversion operations. +neon-vfpv4 The Advanced SIMD (Neon) v2 and the VFPv4 floating-point instructions. +nosimd Disable the Advanced SIMD instructions (does not disable floating point). +nofp Disable the floating-point and Advanced SIMD instructions. armv7ve The extended version of the ARMv7-A architecture with support for virtualization. +fp The VFPv4 floating-point instructions, with 16 double-precision registers. The extension +vfpv4-d16 can be used as an alias for this extension. +simd The Advanced SIMD (Neon) v2 and the VFPv4 floating-point instructions. The extension +neon-vfpv4 can be used as an alias for this extension. +vfpv3-d16 The VFPv3 floating-point instructions, with 16 double-precision registers. +vfpv3 The VFPv3 floating-point instructions, with 32 double-precision registers. +vfpv3-d16-fp16 The VFPv3 floating-point instructions, with 16 double-precision registers and the half-precision floating-point conversion operations. +vfpv3-fp16 The VFPv3 floating-point instructions, with 32 double-precision registers and the half-precision floating-point conversion operations. +vfpv4-d16 The VFPv4 floating-point instructions, with 16 double-precision registers. +vfpv4 The VFPv4 floating-point instructions, with 32 double-precision registers. +neon The Advanced SIMD (Neon) v1 and the VFPv3 floating-point instructions. The extension +neon-vfpv3 can be used as an alias for this extension. +neon-fp16 The Advanced SIMD (Neon) v1 and the VFPv3 floating-point instructions, with the half-precision floating-point conversion operations. +nosimd Disable the Advanced SIMD instructions (does not disable floating point). +nofp Disable the floating-point and Advanced SIMD instructions. armv8-a +crc The Cyclic Redundancy Check (CRC) instructions. +simd The ARMv8-A Advanced SIMD and floating-point instructions. +crypto The cryptographic instructions. +nocrypto Disable the cryptographic instructions. +nofp Disable the floating-point, Advanced SIMD and cryptographic instructions. +sb Speculation Barrier Instruction. +predres Execution and Data Prediction Restriction Instructions. armv8.1-a +simd The ARMv8.1-A Advanced SIMD and floating-point instructions. +crypto The cryptographic instructions. This also enables the Advanced SIMD and floating-point instructions. +nocrypto Disable the cryptographic instructions. +nofp Disable the floating-point, Advanced SIMD and cryptographic instructions. +sb Speculation Barrier Instruction. +predres Execution and Data Prediction Restriction Instructions. armv8.2-a armv8.3-a +fp16 The half-precision floating-point data processing instructions. This also enables the Advanced SIMD and floating-point instructions. +fp16fml The half-precision floating-point fmla extension. This also enables the half- precision floating-point extension and Advanced SIMD and floating-point instructions. +simd The ARMv8.1-A Advanced SIMD and floating-point instructions. +crypto The cryptographic instructions. This also enables the Advanced SIMD and floating-point instructions. +dotprod Enable the Dot Product extension. This also enables Advanced SIMD instructions. +nocrypto Disable the cryptographic extension. +nofp Disable the floating-point, Advanced SIMD and cryptographic instructions. +sb Speculation Barrier Instruction. +predres Execution and Data Prediction Restriction Instructions. +i8mm 8-bit Integer Matrix Multiply instructions. This also enables Advanced SIMD and floating-point instructions. +bf16 Brain half-precision floating-point instructions. This also enables Advanced SIMD and floating-point instructions. armv8.4-a +fp16 The half-precision floating-point data processing instructions. This also enables the Advanced SIMD and floating-point instructions as well as the Dot Product extension and the half-precision floating-point fmla extension. +simd The ARMv8.3-A Advanced SIMD and floating-point instructions as well as the Dot Product extension. +crypto The cryptographic instructions. This also enables the Advanced SIMD and floating-point instructions as well as the Dot Product extension. +nocrypto Disable the cryptographic extension. +nofp Disable the floating-point, Advanced SIMD and cryptographic instructions. +sb Speculation Barrier Instruction. +predres Execution and Data Prediction Restriction Instructions. +i8mm 8-bit Integer Matrix Multiply instructions. This also enables Advanced SIMD and floating-point instructions. +bf16 Brain half-precision floating-point instructions. This also enables Advanced SIMD and floating-point instructions. armv8.5-a +fp16 The half-precision floating-point data processing instructions. This also enables the Advanced SIMD and floating-point instructions as well as the Dot Product extension and the half-precision floating-point fmla extension. +simd The ARMv8.3-A Advanced SIMD and floating-point instructions as well as the Dot Product extension. +crypto The cryptographic instructions. This also enables the Advanced SIMD and floating-point instructions as well as the Dot Product extension. +nocrypto Disable the cryptographic extension. +nofp Disable the floating-point, Advanced SIMD and cryptographic instructions. +i8mm 8-bit Integer Matrix Multiply instructions. This also enables Advanced SIMD and floating-point instructions. +bf16 Brain half-precision floating-point instructions. This also enables Advanced SIMD and floating-point instructions. armv8.6-a +fp16 The half-precision floating-point data processing instructions. This also enables the Advanced SIMD and floating-point instructions as well as the Dot Product extension and the half-precision floating-point fmla extension. +simd The ARMv8.3-A Advanced SIMD and floating-point instructions as well as the Dot Product extension. +crypto The cryptographic instructions. This also enables the Advanced SIMD and floating-point instructions as well as the Dot Product extension. +nocrypto Disable the cryptographic extension. +nofp Disable the floating-point, Advanced SIMD and cryptographic instructions. +i8mm 8-bit Integer Matrix Multiply instructions. This also enables Advanced SIMD and floating-point instructions. +bf16 Brain half-precision floating-point instructions. This also enables Advanced SIMD and floating-point instructions. armv7-r +fp.sp The single-precision VFPv3 floating-point instructions. The extension +vfpv3xd can be used as an alias for this extension. +fp The VFPv3 floating-point instructions with 16 double-precision registers. The extension +vfpv3-d16 can be used as an alias for this extension. +vfpv3xd-d16-fp16 The single-precision VFPv3 floating-point instructions with 16 double-precision registers and the half-precision floating-point conversion operations. +vfpv3-d16-fp16 The VFPv3 floating-point instructions with 16 double-precision registers and the half-precision floating-point conversion operations. +nofp Disable the floating-point extension. +idiv The ARM-state integer division instructions. +noidiv Disable the ARM-state integer division extension. armv7e-m +fp The single-precision VFPv4 floating-point instructions. +fpv5 The single-precision FPv5 floating-point instructions. +fp.dp The single- and double-precision FPv5 floating-point instructions. +nofp Disable the floating-point extensions. armv8.1-m.main +dsp The DSP instructions. +mve The M-Profile Vector Extension (MVE) integer instructions. +mve.fp The M-Profile Vector Extension (MVE) integer and single precision floating-point instructions. +fp The single-precision floating-point instructions. +fp.dp The single- and double-precision floating-point instructions. +nofp Disable the floating-point extension. +cdecp0, +cdecp1, ... , +cdecp7 Enable the Custom Datapath Extension (CDE) on selected coprocessors according to the numbers given in the options in the range 0 to 7. +pacbti Enable the Pointer Authentication and Branch Target Identification Extension. armv8-m.main +dsp The DSP instructions. +nodsp Disable the DSP extension. +fp The single-precision floating-point instructions. +fp.dp The single- and double-precision floating-point instructions. +nofp Disable the floating-point extension. +cdecp0, +cdecp1, ... , +cdecp7 Enable the Custom Datapath Extension (CDE) on selected coprocessors according to the numbers given in the options in the range 0 to 7. armv8-r +crc The Cyclic Redundancy Check (CRC) instructions. +fp.sp The single-precision FPv5 floating-point instructions. +simd The ARMv8-A Advanced SIMD and floating-point instructions. +crypto The cryptographic instructions. +nocrypto Disable the cryptographic instructions. +nofp Disable the floating-point, Advanced SIMD and cryptographic instructions. -march=native causes the compiler to auto-detect the architecture of the build computer. At present, this feature is only supported on GNU/Linux, and not all architectures are recognized. If the auto-detect is unsuccessful the option has no effect."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option specifies the name of the target ARM processor for which GCC should tune the performance of the code. For some ARM implementations better performance can be obtained by using this option. Permissible names are: arm7tdmi, arm7tdmi-s, arm710t, arm720t, arm740t, strongarm, strongarm110, strongarm1100, strongarm1110, arm8, arm810, arm9, arm9e, arm920, arm920t, arm922t, arm946e-s, arm966e-s, arm968e-s, arm926ej-s, arm940t, arm9tdmi, arm10tdmi, arm1020t, arm1026ej-s, arm10e, arm1020e, arm1022e, arm1136j-s, arm1136jf-s, mpcore, mpcorenovfp, arm1156t2-s, arm1156t2f-s, arm1176jz-s, arm1176jzf-s, generic-armv7-a, cortex-a5, cortex-a7, cortex-a8, cortex-a9, cortex-a12, cortex-a15, cortex-a17, cortex-a32, cortex-a35, cortex-a53, cortex-a55, cortex-a57, cortex-a72, cortex-a73, cortex-a75, cortex-a76, cortex-a76ae, cortex-a77, cortex-a78, cortex-a78ae, cortex-a78c, cortex-a710, ares, cortex-r4, cortex-r4f, cortex-r5, cortex-r7, cortex-r8, cortex-r52, cortex-r52plus, cortex-m0, cortex-m0plus, cortex-m1, cortex-m3, cortex-m4, cortex-m7, cortex-m23, cortex-m33, cortex-m35p, cortex-m55, cortex-m85, cortex-x1, cortex-x1c, cortex-m1.small-multiply, cortex-m0.small-multiply, cortex-m0plus.small-multiply, exynos-m1, marvell-pj4, neoverse-n1, neoverse-n2, neoverse-v1, xscale, iwmmxt, iwmmxt2, ep9312, fa526, fa626, fa606te, fa626te, fmp626, fa726te, star-mc1, xgene1. Additionally, this option can specify that GCC should tune the performance of the code for a big.LITTLE system. Permissible names are: cortex-a15.cortex-a7, cortex-a17.cortex-a7, cortex-a57.cortex-a53, cortex-a72.cortex-a53, cortex-a72.cortex-a35, cortex-a73.cortex-a53, cortex-a75.cortex-a55, cortex-a76.cortex-a55. -mtune=generic-arch specifies that GCC should tune the performance for a blend of processors within architecture arch. The aim is to generate code that run well on the current most popular processors, balancing between optimizations that benefit some CPUs in the range, and avoiding performance pitfalls of other CPUs. The effects of this option may change in future GCC versions as CPU models come and go. -mtune permits the same extension options as -mcpu, but the extension options do not affect the tuning of the generated code. -mtune=native causes the compiler to auto-detect the CPU of the build computer. At present, this feature is only supported on GNU/Linux, and not all architectures are recognized. If the auto-detect is unsuccessful the option has no effect."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This specifies the name of the target ARM processor. GCC uses this name to derive the name of the target ARM architecture (as if specified by -march) and the ARM processor type for which to tune for performance (as if specified by -mtune). Where this option is used in conjunction with -march or -mtune, those options take precedence over the appropriate part of this option. Many of the supported CPUs implement optional architectural extensions. Where this is so the architectural extensions are normally enabled by default. If implementations that lack the extension exist, then the extension syntax can be used to disable those extensions that have been omitted. For floating-point and Advanced SIMD (Neon) instructions, the settings of the options -mfloat-abi and -mfpu must also be considered: floating-point and Advanced SIMD instructions will only be used if -mfloat-abi is not set to soft; and any setting of -mfpu other than auto will override the available floating- point and SIMD extension instructions. For example, cortex-a9 can be found in three major configurations: integer only, with just a floating-point unit or with floating-point and Advanced SIMD. The default is to enable all the instructions, but the extensions +nosimd and +nofp can be used to disable just the SIMD or both the SIMD and floating-point instructions respectively. Permissible names for this option are the same as those for -mtune. The following extension options are common to the listed CPUs: +nodsp Disable the DSP instructions on cortex-m33, cortex-m35p, cortex-m55 and cortex-m85. Also disable the M-Profile Vector Extension (MVE) integer and single precision floating-point instructions on cortex-m55 and cortex-m85. +nopacbti Disable the Pointer Authentication and Branch Target Identification Extension on cortex-m85. +nomve Disable the M-Profile Vector Extension (MVE) integer and single precision floating- point instructions on cortex-m55 and cortex-m85. +nomve.fp Disable the M-Profile Vector Extension (MVE) single precision floating-point instructions on cortex-m55 and cortex-m85. +cdecp0, +cdecp1, ... , +cdecp7 Enable the Custom Datapath Extension (CDE) on selected coprocessors according to the numbers given in the options in the range 0 to 7 on cortex-m55. +nofp Disables the floating-point instructions on arm9e, arm946e-s, arm966e-s, arm968e-s, arm10e, arm1020e, arm1022e, arm926ej-s, arm1026ej-s, cortex-r5, cortex-r7, cortex-r8, cortex-m4, cortex-m7, cortex-m33, cortex-m35p cortex-m4, cortex-m7, cortex-m33, cortex-m35p, cortex-m55 and cortex-m85. Disables the floating-point and SIMD instructions on generic-armv7-a, cortex-a5, cortex-a7, cortex-a8, cortex-a9, cortex-a12, cortex-a15, cortex-a17, cortex-a15.cortex-a7, cortex-a17.cortex-a7, cortex-a32, cortex-a35, cortex-a53 and cortex-a55. +nofp.dp Disables the double-precision component of the floating-point instructions on cortex-r5, cortex-r7, cortex-r8, cortex-r52, cortex-r52plus and cortex-m7. +nosimd Disables the SIMD (but not floating-point) instructions on generic-armv7-a, cortex-a5, cortex-a7 and cortex-a9. +crypto Enables the cryptographic instructions on cortex-a32, cortex-a35, cortex-a53, cortex-a55, cortex-a57, cortex-a72, cortex-a73, cortex-a75, exynos-m1, xgene1, cortex-a57.cortex-a53, cortex-a72.cortex-a53, cortex-a73.cortex-a35, cortex-a73.cortex-a53 and cortex-a75.cortex-a55. Additionally the generic-armv7-a pseudo target defaults to VFPv3 with 16 double-precision registers. It supports the following extension options: mp, sec, vfpv3-d16, vfpv3, vfpv3-d16-fp16, vfpv3-fp16, vfpv4-d16, vfpv4, neon, neon-vfpv3, neon-fp16, neon-vfpv4. The meanings are the same as for the extensions to -march=armv7-a. -mcpu=generic-arch is also permissible, and is equivalent to -march=arch -mtune=generic-arch. See -mtune for more information. -mcpu=native causes the compiler to auto-detect the CPU of the build computer. At present, this feature is only supported on GNU/Linux, and not all architectures are recognized. If the auto-detect is unsuccessful the option has no effect."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This specifies what floating-point hardware (or hardware emulation) is available on the target. Permissible names are: auto, vfpv2, vfpv3, vfpv3-fp16, vfpv3-d16, vfpv3-d16-fp16, vfpv3xd, vfpv3xd-fp16, neon-vfpv3, neon-fp16, vfpv4, vfpv4-d16, fpv4-sp-d16, neon-vfpv4, fpv5-d16, fpv5-sp-d16, fp-armv8, neon-fp-armv8 and crypto-neon-fp-armv8. Note that neon is an alias for neon-vfpv3 and vfp is an alias for vfpv2. The setting auto is the default and is special. It causes the compiler to select the floating-point and Advanced SIMD instructions based on the settings of -mcpu and -march. If the selected floating-point hardware includes the NEON extension (e.g. -mfpu=neon), note that floating-point operations are not generated by GCC's auto-vectorization pass unless -funsafe-math-optimizations is also specified. This is because NEON hardware does not fully implement the IEEE 754 standard for floating-point arithmetic (in particular denormal values are treated as zero), so the use of NEON instructions may lead to a loss of precision. You can also set the fpu name at function level by using the target(\"fpu=\") function attributes or pragmas."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the format of the \"fp16\" half-precision floating-point type. Permissible names are none, ieee, and alternative; the default is none, in which case the \"fp16\" type is not defined."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The sizes of all structures and unions are rounded up to a multiple of the number of bits set by this option. Permissible values are 8, 32 and 64. The default value varies for different toolchains. For the COFF targeted toolchain the default value is 8. A value of 64 is only allowed if the underlying ABI supports it. Specifying a larger number can produce faster, more efficient code, but can also increase the size of the program. Different values are potentially incompatible. Code compiled with one value cannot necessarily expect to work with code or libraries compiled with another value, if they exchange information using structures or unions. This option is deprecated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate a call to the function \"abort\" at the end of a \"noreturn\" function. It is executed if the function tries to return."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Tells the compiler to perform function calls by first loading the address of the function into a register and then performing a subroutine call on this register. This switch is needed if the target function lies outside of the 64-megabyte addressing range of the offset-based version of subroutine call instruction. Even if this switch is enabled, not all function calls are turned into long calls. The heuristic is that static functions, functions that have the \"shortcall\" attribute, functions that are inside the scope of a \"#pragma nolongcalls\" directive, and functions whose definitions have already been compiled within the current compilation unit are not turned into long calls. The exceptions to this rule are that weak function definitions, functions with the \"longcall\" attribute or the \"section\" attribute, and functions that are within the scope of a \"#pragma longcalls\" directive are always turned into long calls. This feature is not enabled by default. Specifying -mno-long-calls restores the default behavior, as does placing the function calls within the scope of a \"#pragma longcallsoff\" directive. Note these switches have no effect on how the compiler generates code to handle function calls via function pointers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Treat the register used for PIC addressing as read-only, rather than loading it in the prologue for each function. The runtime system is responsible for initializing this register with an appropriate value before execution begins."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the register to be used for PIC addressing. For standard PIC base case, the default is any suitable register determined by compiler. For single PIC base case, the default is R9 if target is EABI based or stack-checking is enabled, otherwise the default is R10."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that the displacement between the text and data segments is fixed at static link time. This permits using PC-relative addressing operations to access data known to be in the data segment. For non-VxWorks RTP targets, this option is enabled by default. When disabled on such targets, it will enable -msingle-pic-base by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Write the name of each function into the text section, directly preceding the function prologue. The generated code is similar to this: t0 .ascii \"armpokefunctionname\", 0 .align t1 .word 0xff000000 + (t1 - t0) armpokefunctionname mov ip, sp stmfd sp!, {fp, ip, lr, pc} sub fp, ip, #4 When performing a stack backtrace, code can inspect the value of \"pc\" stored at \"fp + 0\". If the trace function then looks at location \"pc - 12\" and the top 8 bits are set, then we know that there is a function name embedded immediately preceding this location and has length \"((pc[-3]) & 0xff000000)\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select between generating code that executes in ARM and Thumb states. The default for most configurations is to generate code that executes in ARM state, but the default can be changed by configuring GCC with the --with-mode=state configure option. You can also override the ARM and Thumb mode for each function by using the target(\"thumb\") and target(\"arm\") function attributes or pragmas."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Switch ARM/Thumb modes on alternating functions. This option is provided for regression testing of mixed Thumb/ARM code generation, and is not intended for ordinary use in compiling code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate a stack frame that is compliant with the Thumb Procedure Call Standard for all non-leaf functions. (A leaf function is one that does not call any other functions.) The default is -mno-tpcs-frame."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate a stack frame that is compliant with the Thumb Procedure Call Standard for all leaf functions. (A leaf function is one that does not call any other functions.) The default is -mno-apcs-leaf-frame."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Gives all externally visible functions in the file being compiled an ARM instruction set header which switches to Thumb mode before executing the rest of the function. This allows these functions to be called from non-interworking code. This option is not valid in AAPCS configurations because interworking is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allows calls via function pointers (including virtual functions) to execute correctly regardless of whether the target code has been compiled for interworking or not. There is a small overhead in the cost of executing a function pointer if this option is enabled. This option is not valid in AAPCS configurations because interworking is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the access model for the thread local storage pointer. The valid models are soft, which generates calls to \"aeabireadtp\", cp15, which fetches the thread pointer from \"cp15\" directly (supported in the arm6k architecture), and auto, which uses the best available method for the selected processor. The default setting is auto."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the dialect to use for accessing thread local storage. Two dialects are supported---gnu and gnu2. The gnu dialect selects the original GNU scheme for supporting local and global dynamic TLS models. The gnu2 dialect selects the GNU descriptor scheme, which provides better performance for shared libraries. The GNU descriptor scheme is compatible with the original scheme, but does require new assembler, linker and library support. Initial and local exec TLS models are unaffected by this option and always use the original scheme."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Only generate absolute relocations on word-sized values (i.e. RARMABS32). This is enabled by default on targets (uClinux, SymbianOS) where the runtime loader imposes this restriction, and when -fpic or -fPIC is specified. This option conflicts with -mslow-flash-data."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Some Cortex-M3 cores can cause data corruption when \"ldrd\" instructions with overlapping destination and base registers are used. This option avoids generating these instructions. This option is enabled by default when -mcpu=cortex-m3 is specified."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable (disable) mitigation for an erratum on Cortex-A57 and Cortex-A72 that affects the AES cryptographic instructions. This option is enabled by default when either -mcpu=cortex-a57 or -mcpu=cortex-a72 is specified."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enables (or disables) reading and writing of 16- and 32- bit values from addresses that are not 16- or 32- bit aligned. By default unaligned access is disabled for all pre-ARMv6, all ARMv6-M and for ARMv8-M Baseline architectures, and enabled for all other architectures. If unaligned access is not enabled then words in packed data structures are accessed a byte at a time. The ARM attribute \"TagCPUunalignedaccess\" is set in the generated object file to either true or false, depending upon the setting of this option. If unaligned access is enabled then the preprocessor symbol \"ARMFEATUREUNALIGNED\" is also defined."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is deprecated and has no effect."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume loading data from flash is slower than fetching instruction. Therefore literal load is minimized for better performance. This option is only supported when compiling for ARMv7 M-profile and off by default. It conflicts with -mword-relocations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume inline assembler is using unified asm syntax. The default is currently off which implies divided syntax. This option has no impact on Thumb2. However, this may change in future releases of GCC. Divided syntax should be considered deprecated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Restricts generation of IT blocks to conform to the rules of ARMv8-A. IT blocks can only contain a single 16-bit instruction from a select set of instructions. This option is on by default for ARMv8-A Thumb mode."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print CPU tuning information as comment in assembler file. This is an option used only for regression testing of the compiler and not intended for ordinary use in compiling code. This option is disabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable verbose cost model dumping in the debug dump files. This option is provided for use in debugging the compiler."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not allow constant data to be placed in code sections. Additionally, when compiling for ELF object format give all text sections the ELF processor-specific section attribute \"SHFARMPURECODE\". This option is only available when generating non-pic code for M-profile targets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate secure code as per the \"ARMv8-M Security Extensions: Requirements on Development Tools Engineering Specification\", which can be found on <https://developer.arm.com/documentation/ecm0359818/latest/>."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Mitigate against a potential security issue with the \"VLLDM\" instruction in some M-profile devices when using CMSE (CVE-2021-365465). This option is enabled by default when the option -mcpu= is used with \"cortex-m33\", \"cortex-m35p\", \"cortex-m55\", \"cortex-m85\" or \"star-mc1\". The option -mno-fix-cmse-cve-2021-35465 can be used to disable the mitigation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate stack protection code using canary at guard. Supported locations are global for a global canary or tls for a canary accessible via the TLS register. The option -mstack-protector-guard-offset= is for use with -fstack-protector-guard=tls and not for use in user-land code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select the FDPIC ABI, which uses 64-bit function descriptors to represent pointers to functions. When the compiler is configured for \"arm-*-uclinuxfdpiceabi\" targets, this option is on by default and implies -fPIE if none of the PIC/PIE-related options is provided. On other targets, it only enables the FDPIC-specific code generation features, and the user should explicitly provide the PIC/PIE-related options as needed. Note that static linking is not supported because it would still involve the dynamic linker when the program self-relocates. If such behavior is acceptable, use -static and -Wl,-dynamic-linker options. The opposite -mno-fdpic option is useful (and required) to build the Linux kernel using the same (\"arm-*-uclinuxfdpiceabi\") toolchain as the one used to build the userland programs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable branch protection features (armv8.1-m.main only). none generate code without branch protection or return address signing. standard[+leaf] generate code with all branch protection features enabled at their standard level. pac-ret[+leaf] generate code with return address signing set to its standard level, which is to sign all functions that save the return address to memory. leaf When return address signing is enabled, also sign leaf functions even if they do not write the return address to memory. +bti Add landing-pad instructions at the permitted targets of indirect branch instructions. If the +pacbti architecture extension is not enabled, then all branch protection and return address signing operations are constrained to use only the instructions defined in the architectural-NOP space. The generated code will remain backwards-compatible with earlier versions of the architecture, but the additional security can be enabled at run time on processors that support the PACBTI extension. Branch target enforcement using BTI can only be enabled at runtime if all code in the application has been compiled with at least -mbranch-protection=bti. Any setting other than none is supported only on armv8-m.main or later. The default is to generate code without branch protection or return address signing. AVR Options These options are defined for AVR implementations:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the AVR instruction set architecture (ISA) or device type. The default for this option is \"avr2\". The following AVR devices and ISAs are supported. Note: A complete device support consists of startup code \"crtmcu.o\", a device header \"avr/io*.h\", a device library \"libmcu.a\" and a device-specs (\"https://gcc.gnu.org/wiki/avr-gcc#spec-files\") file \"specs-mcu\". Only the latter is provided by the compiler according the supported \"mcu\"s below. The rest is supported by AVR-LibC (\"https://www.nongnu.org/avr-libc/\"), or by means of \"atpack\" (\"https://gcc.gnu.org/wiki/avr-gcc#atpack\") files from the hardware manufacturer. \"avr2\" \"Classic\" devices with up to 8 KiB of program memory. mcu = \"attiny22\", \"attiny26\", \"at90s2313\", \"at90s2323\", \"at90s2333\", \"at90s2343\", \"at90s4414\", \"at90s4433\", \"at90s4434\", \"at90c8534\", \"at90s8515\", \"at90s8535\". \"avr25\" \"Classic\" devices with up to 8 KiB of program memory and with the \"MOVW\" instruction. mcu = \"attiny13\", \"attiny13a\", \"attiny24\", \"attiny24a\", \"attiny25\", \"attiny261\", \"attiny261a\", \"attiny2313\", \"attiny2313a\", \"attiny43u\", \"attiny44\", \"attiny44a\", \"attiny45\", \"attiny48\", \"attiny441\", \"attiny461\", \"attiny461a\", \"attiny4313\", \"attiny84\", \"attiny84a\", \"attiny85\", \"attiny87\", \"attiny88\", \"attiny828\", \"attiny841\", \"attiny861\", \"attiny861a\", \"ata5272\", \"ata6616c\", \"at86rf401\". \"avr3\" \"Classic\" devices with 16 KiB up to 64 KiB of program memory. mcu = \"at76c711\", \"at43usb355\". \"avr31\" \"Classic\" devices with 128 KiB of program memory. mcu = \"atmega103\", \"at43usb320\". \"avr35\" \"Classic\" devices with 16 KiB up to 64 KiB of program memory and with the \"MOVW\" instruction. mcu = \"attiny167\", \"attiny1634\", \"atmega8u2\", \"atmega16u2\", \"atmega32u2\", \"ata5505\", \"ata6617c\", \"ata664251\", \"at90usb82\", \"at90usb162\". \"avr4\" \"Enhanced\" devices with up to 8 KiB of program memory. mcu = \"atmega48\", \"atmega48a\", \"atmega48p\", \"atmega48pa\", \"atmega48pb\", \"atmega8\", \"atmega8a\", \"atmega8hva\", \"atmega88\", \"atmega88a\", \"atmega88p\", \"atmega88pa\", \"atmega88pb\", \"atmega8515\", \"atmega8535\", \"ata5795\", \"ata6285\", \"ata6286\", \"ata6289\", \"ata6612c\", \"at90pwm1\", \"at90pwm2\", \"at90pwm2b\", \"at90pwm3\", \"at90pwm3b\", \"at90pwm81\". \"avr5\" \"Enhanced\" devices with 16 KiB up to 64 KiB of program memory. mcu = \"atmega16\", \"atmega16a\", \"atmega16hva\", \"atmega16hva2\", \"atmega16hvb\", \"atmega16hvbrevb\", \"atmega16m1\", \"atmega16u4\", \"atmega161\", \"atmega162\", \"atmega163\", \"atmega164a\", \"atmega164p\", \"atmega164pa\", \"atmega165\", \"atmega165a\", \"atmega165p\", \"atmega165pa\", \"atmega168\", \"atmega168a\", \"atmega168p\", \"atmega168pa\", \"atmega168pb\", \"atmega169\", \"atmega169a\", \"atmega169p\", \"atmega169pa\", \"atmega32\", \"atmega32a\", \"atmega32c1\", \"atmega32hvb\", \"atmega32hvbrevb\", \"atmega32m1\", \"atmega32u4\", \"atmega32u6\", \"atmega323\", \"atmega324a\", \"atmega324p\", \"atmega324pa\", \"atmega324pb\", \"atmega325\", \"atmega325a\", \"atmega325p\", \"atmega325pa\", \"atmega328\", \"atmega328p\", \"atmega328pb\", \"atmega329\", \"atmega329a\", \"atmega329p\", \"atmega329pa\", \"atmega3250\", \"atmega3250a\", \"atmega3250p\", \"atmega3250pa\", \"atmega3290\", \"atmega3290a\", \"atmega3290p\", \"atmega3290pa\", \"atmega406\", \"atmega64\", \"atmega64a\", \"atmega64c1\", \"atmega64hve\", \"atmega64hve2\", \"atmega64m1\", \"atmega64rfr2\", \"atmega640\", \"atmega644\", \"atmega644a\", \"atmega644p\", \"atmega644pa\", \"atmega644rfr2\", \"atmega645\", \"atmega645a\", \"atmega645p\", \"atmega649\", \"atmega649a\", \"atmega649p\", \"atmega6450\", \"atmega6450a\", \"atmega6450p\", \"atmega6490\", \"atmega6490a\", \"atmega6490p\", \"ata5790\", \"ata5790n\", \"ata5791\", \"ata6613c\", \"ata6614q\", \"ata5782\", \"ata5831\", \"ata8210\", \"ata8510\", \"ata5787\", \"ata5835\", \"ata5700m322\", \"ata5702m322\", \"at90pwm161\", \"at90pwm216\", \"at90pwm316\", \"at90can32\", \"at90can64\", \"at90scr100\", \"at90usb646\", \"at90usb647\", \"at94k\", \"m3000\". \"avr51\" \"Enhanced\" devices with 128 KiB of program memory. mcu = \"atmega128\", \"atmega128a\", \"atmega128rfa1\", \"atmega128rfr2\", \"atmega1280\", \"atmega1281\", \"atmega1284\", \"atmega1284p\", \"atmega1284rfr2\", \"at90can128\", \"at90usb1286\", \"at90usb1287\". \"avr6\" \"Enhanced\" devices with 3-byte PC, i.e. with more than 128 KiB of program memory. mcu = \"atmega256rfr2\", \"atmega2560\", \"atmega2561\", \"atmega2564rfr2\". \"avrxmega2\" \"XMEGA\" devices with more than 8 KiB and up to 64 KiB of program memory. mcu = \"atxmega8e5\", \"atxmega16a4\", \"atxmega16a4u\", \"atxmega16c4\", \"atxmega16d4\", \"atxmega16e5\", \"atxmega32a4\", \"atxmega32a4u\", \"atxmega32c3\", \"atxmega32c4\", \"atxmega32d3\", \"atxmega32d4\", \"atxmega32e5\", \"avr64da28\", \"avr64da32\", \"avr64da48\", \"avr64da64\", \"avr64db28\", \"avr64db32\", \"avr64db48\", \"avr64db64\", \"avr64dd14\", \"avr64dd20\", \"avr64dd28\", \"avr64dd32\", \"avr64du28\", \"avr64du32\", \"avr64ea28\", \"avr64ea32\", \"avr64ea48\". \"avrxmega3\" \"XMEGA\" devices with up to 64 KiB of combined program memory and RAM, and with program memory visible in the RAM address space. mcu = \"attiny202\", \"attiny204\", \"attiny212\", \"attiny214\", \"attiny402\", \"attiny404\", \"attiny406\", \"attiny412\", \"attiny414\", \"attiny416\", \"attiny416auto\", \"attiny417\", \"attiny424\", \"attiny426\", \"attiny427\", \"attiny804\", \"attiny806\", \"attiny807\", \"attiny814\", \"attiny816\", \"attiny817\", \"attiny824\", \"attiny826\", \"attiny827\", \"attiny1604\", \"attiny1606\", \"attiny1607\", \"attiny1614\", \"attiny1616\", \"attiny1617\", \"attiny1624\", \"attiny1626\", \"attiny1627\", \"attiny3214\", \"attiny3216\", \"attiny3217\", \"attiny3224\", \"attiny3226\", \"attiny3227\", \"atmega808\", \"atmega809\", \"atmega1608\", \"atmega1609\", \"atmega3208\", \"atmega3209\", \"atmega4808\", \"atmega4809\", \"avr16dd14\", \"avr16dd20\", \"avr16dd28\", \"avr16dd32\", \"avr16du14\", \"avr16du20\", \"avr16du28\", \"avr16du32\", \"avr16ea28\", \"avr16ea32\", \"avr16ea48\", \"avr16eb14\", \"avr16eb20\", \"avr16eb28\", \"avr16eb32\", \"avr32da28\", \"avr32da32\", \"avr32da48\", \"avr32db28\", \"avr32db32\", \"avr32db48\", \"avr32dd14\", \"avr32dd20\", \"avr32dd28\", \"avr32dd32\", \"avr32du14\", \"avr32du20\", \"avr32du28\", \"avr32du32\", \"avr32ea28\", \"avr32ea32\", \"avr32ea48\". \"avrxmega4\" \"XMEGA\" devices with more than 64 KiB and up to 128 KiB of program memory. mcu = \"atxmega64a3\", \"atxmega64a3u\", \"atxmega64a4u\", \"atxmega64b1\", \"atxmega64b3\", \"atxmega64c3\", \"atxmega64d3\", \"atxmega64d4\", \"avr128da28\", \"avr128da32\", \"avr128da48\", \"avr128da64\", \"avr128db28\", \"avr128db32\", \"avr128db48\", \"avr128db64\". \"avrxmega5\" \"XMEGA\" devices with more than 64 KiB and up to 128 KiB of program memory and more than 64 KiB of RAM. mcu = \"atxmega64a1\", \"atxmega64a1u\". \"avrxmega6\" \"XMEGA\" devices with more than 128 KiB of program memory. mcu = \"atxmega128a3\", \"atxmega128a3u\", \"atxmega128b1\", \"atxmega128b3\", \"atxmega128c3\", \"atxmega128d3\", \"atxmega128d4\", \"atxmega192a3\", \"atxmega192a3u\", \"atxmega192c3\", \"atxmega192d3\", \"atxmega256a3\", \"atxmega256a3b\", \"atxmega256a3bu\", \"atxmega256a3u\", \"atxmega256c3\", \"atxmega256d3\", \"atxmega384c3\", \"atxmega384d3\". \"avrxmega7\" \"XMEGA\" devices with more than 128 KiB of program memory and more than 64 KiB of RAM. mcu = \"atxmega128a1\", \"atxmega128a1u\", \"atxmega128a4u\". \"avrtiny\" \"TINY\" Tiny core devices with 512 B up to 4 KiB of program memory. mcu = \"attiny4\", \"attiny5\", \"attiny9\", \"attiny10\", \"attiny102\", \"attiny104\", \"attiny20\", \"attiny40\". \"avr1\" This ISA is implemented by the minimal AVR core and supported for assembler only. mcu = \"attiny11\", \"attiny12\", \"attiny15\", \"attiny28\", \"at90s1200\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that all data in static storage can be accessed by LDS / STS instructions. This option has only an effect on reduced Tiny devices like ATtiny40. See also the \"absdata\" AVR Variable Attributes,variable attribute."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Accumulate outgoing function arguments and acquire/release the needed stack space for outgoing function arguments once in function prologue/epilogue. Without this option, outgoing arguments are pushed before calling a function and popped afterwards. Popping the arguments after the function call can be expensive on AVR so that accumulating the stack space might lead to smaller executables because arguments need not be removed from the stack after such a function call. This option can lead to reduced code size for functions that perform several calls to functions that get their arguments on the stack like calls to printf-like functions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the branch costs for conditional branch instructions to cost. Reasonable values for cost are small, non-negative integers. The default branch cost is 0."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Functions prologues/epilogues are expanded as calls to appropriate subroutines. Code size is smaller."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the size (in bits) of the \"double\" or \"long double\" type, respectively. Possible values for bits are 32 and 64. Whether or not a specific value for bits is allowed depends on the \"--with-double=\" and \"--with-long-double=\" configure options (\"https://gcc.gnu.org/install/configure.html#avr\"), and the same applies for the default values of the options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Interrupt service routines (ISRs) may use the \"gccisr\" pseudo instruction supported by GNU Binutils. If this option is on, the feature can still be disabled for individual ISRs by means of the AVR Function Attributes,,\"nogccisr\" function attribute. This feature is activated per default if optimization is on (but not with -Og, @pxref{Optimize Options}), and if GNU Binutils support PR21683 (\"https://sourceware.org/PR21683\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume \"int\" to be 8-bit integer. This affects the sizes of all types: a \"char\" is 1 byte, an \"int\" is 1 byte, a \"long\" is 2 bytes, and \"long long\" is 4 bytes. Please note that this option does not conform to the C standards, but it results in smaller code size."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not save registers in \"main\". The effect is the same like attaching attribute AVR Function Attributes,,\"OStask\" to \"main\". It is activated per default if optimization is on."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generated code is not compatible with hardware interrupts. Code size is smaller."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Try to replace \"CALL\" resp. \"JMP\" instruction by the shorter \"RCALL\" resp. \"RJMP\" instruction if applicable. Setting -mrelax just adds the --mlink-relax option to the assembler's command line and the --relax option to the linker's command line. Jump relaxing is performed by the linker because jump offsets are not known before code is located. Therefore, the assembler code generated by the compiler is the same, but the instructions in the executable may differ from instructions in the assembler code. Relaxing must be turned on if linker stubs are needed, see the section on \"EIND\" and linker stubs below."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use address register \"X\" in a way proposed by the hardware. This means that \"X\" is only used in indirect, post-increment or pre-decrement addressing. Without this option, the \"X\" register may be used in the same way as \"Y\" or \"Z\" which then is emulated by additional instructions. For example, loading a value with \"X+const\" addressing with a small non-negative \"const < 64\" to a register Rn is performed as adiw r26, const ; X += const ld <Rn>, X ; <Rn> = *X sbiw r26, const ; X -= const"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Only change the lower 8 bits of the stack pointer."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow to use truncation instead of rounding towards zero for fractional fixed-point types."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't link against AVR-LibC's device specific library \"lib<mcu>.a\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't add -specs=device-specs/specs-mcu to the compiler driver's command line. The user takes responsibility for supplying the sub-processes like compiler proper, assembler and linker with appropriate command line options. This means that the user has to supply her private device specs file by means of -specs=path-to-specs-file. There is no more need for option -mmcu=mcu. This option can also serve as a replacement for the older way of specifying custom device-specs files that needed -B some-path to point to a directory which contains a folder named \"device-specs\" which contains a specs file named \"specs-mcu\", where mcu was specified by -mmcu=mcu."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn about conversions between address spaces in the case where the resulting address space is not contained in the incoming address space."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if the ISR is misspelled, i.e. without vector prefix. Enabled by default. \"EIND\" and Devices with More Than 128 Ki Bytes of Flash Pointers in the implementation are 16 bits wide. The address of a function or label is represented as word address so that indirect jumps and calls can target any code address in the range of 64 Ki words. In order to facilitate indirect jump on devices with more than 128 Ki bytes of program memory space, there is a special function register called \"EIND\" that serves as most significant part of the target address when \"EICALL\" or \"EIJMP\" instructions are used. Indirect jumps and calls on these devices are handled as follows by the compiler and are subject to some limitations: * The compiler never sets \"EIND\". * The compiler uses \"EIND\" implicitly in \"EICALL\"/\"EIJMP\" instructions or might read \"EIND\" directly in order to emulate an indirect call/jump by means of a \"RET\" instruction. * The compiler assumes that \"EIND\" never changes during the startup code or during the application. In particular, \"EIND\" is not saved/restored in function or interrupt service routine prologue/epilogue. * For indirect calls to functions and computed goto, the linker generates stubs. Stubs are jump pads sometimes also called trampolines. Thus, the indirect call/jump jumps to such a stub. The stub contains a direct jump to the desired address. * Linker relaxation must be turned on so that the linker generates the stubs correctly in all situations. See the compiler option -mrelax and the linker option --relax. There are corner cases where the linker is supposed to generate stubs but aborts without relaxation and without a helpful error message. * The default linker script is arranged for code with \"EIND = 0\". If code is supposed to work for a setup with \"EIND != 0\", a custom linker script has to be used in order to place the sections whose name start with \".trampolines\" into the segment where \"EIND\" points to. * The startup code from libgcc never sets \"EIND\". Notice that startup code is a blend of code from libgcc and AVR-LibC. For the impact of AVR-LibC on \"EIND\", see the AVR- LibC user manual (\"https://www.nongnu.org/avr-libc/user-manual/\"). * It is legitimate for user-specific startup code to set up \"EIND\" early, for example by means of initialization code located in section \".init3\". Such code runs prior to general startup code that initializes RAM and calls constructors, but after the bit of startup code from AVR-LibC that sets \"EIND\" to the segment where the vector table is located. #include <avr/io.h> static void attribute((section(\".init3\"),naked,used,noinstrumentfunction)) init3seteind (void) { asm volatile (\"ldi r24,pmhh8(trampolinesstart)\\n\\t\" \"out %i0,r24\" :: \"n\" (&EIND) : \"r24\",\"memory\"); } The \"trampolinesstart\" symbol is defined in the linker script. * Stubs are generated automatically by the linker if the following two conditions are met: -<The address of a label is taken by means of the \"gs\" modifier> (short for generate stubs) like so: LDI r24, lo8(gs(<func>)) LDI r25, hi8(gs(<func>)) -<The final location of that label is in a code segment> outside the segment where the stubs are located. * The compiler emits such \"gs\" modifiers for code labels in the following situations: -<Taking address of a function or code label.> -<Computed goto.> -<If prologue-save function is used, see -mcall-prologues> command-line option. -<Switch/case dispatch tables. If you do not want such dispatch> tables you can specify the -fno-jump-tables command-line option. -<C and C++ constructors/destructors called during startup/shutdown.> -<If the tools hit a gs() modifier explained above.> * Jumping to non-symbolic addresses like so is not supported: int main (void) { /* Call function at word address 0x2 */ return ((int(*)(void)) 0x2)(); } Instead, a stub has to be set up, i.e. the function has to be called through a symbol (\"func4\" in the example): int main (void) { extern int func4 (void); /* Call function at byte address 0x4 */ return func4(); } and the application be linked with -Wl,--defsym,func4=0x4. Alternatively, \"func4\" can be defined in the linker script. Handling of the \"RAMPD\", \"RAMPX\", \"RAMPY\" and \"RAMPZ\" Special Function Registers Some AVR devices support memories larger than the 64 KiB range that can be accessed with 16-bit pointers. To access memory locations outside this 64 KiB range, the content of a \"RAMP\" register is used as high part of the address: The \"X\", \"Y\", \"Z\" address register is concatenated with the \"RAMPX\", \"RAMPY\", \"RAMPZ\" special function register, respectively, to get a wide address. Similarly, \"RAMPD\" is used together with direct addressing. * The startup code initializes the \"RAMP\" special function registers with zero. * If a AVR Named Address Spaces,named address space other than generic or \"flash\" is used, then \"RAMPZ\" is set as needed before the operation. * If the device supports RAM larger than 64 KiB and the compiler needs to change \"RAMPZ\" to accomplish an operation, \"RAMPZ\" is reset to zero after the operation. * If the device comes with a specific \"RAMP\" register, the ISR prologue/epilogue saves/restores that SFR and initializes it with zero in case the ISR code might (implicitly) use it. * RAM larger than 64 KiB is not supported by GCC for AVR targets. If you use inline assembler to read from locations outside the 16-bit address range and change one of the \"RAMP\" registers, you must reset it to zero after the access. AVR Built-in Macros GCC defines several built-in macros so that the user code can test for the presence or absence of features. Almost any of the following built-in macros are deduced from device capabilities and thus triggered by the -mmcu= command-line option. For even more AVR-specific built-in macros see AVR Named Address Spaces and AVR Built-in Functions. \"AVRARCH\" Build-in macro that resolves to a decimal number that identifies the architecture and depends on the -mmcu=mcu option. Possible values are: 2, 25, 3, 31, 35, 4, 5, 51, 6 for mcu=\"avr2\", \"avr25\", \"avr3\", \"avr31\", \"avr35\", \"avr4\", \"avr5\", \"avr51\", \"avr6\", respectively and 100, 102, 103, 104, 105, 106, 107 for mcu=\"avrtiny\", \"avrxmega2\", \"avrxmega3\", \"avrxmega4\", \"avrxmega5\", \"avrxmega6\", \"avrxmega7\", respectively. If mcu specifies a device, this built-in macro is set accordingly. For example, with -mmcu=atmega8 the macro is defined to 4. \"AVRDevice\" Setting -mmcu=device defines this built-in macro which reflects the device's name. For example, -mmcu=atmega8 defines the built-in macro \"AVRATmega8\", -mmcu=attiny261a defines \"AVRATtiny261A\", etc. The built-in macros' names follow the scheme \"AVRDevice\" where Device is the device name as from the AVR user manual. The difference between Device in the built-in macro and device in -mmcu=device is that the latter is always lowercase. If device is not a device but only a core architecture like avr51, this macro is not defined. \"AVRDEVICENAME\" Setting -mmcu=device defines this built-in macro to the device's name. For example, with -mmcu=atmega8 the macro is defined to \"atmega8\". If device is not a device but only a core architecture like avr51, this macro is not defined. \"AVRXMEGA\" The device / architecture belongs to the XMEGA family of devices. \"AVRHAVEADIW\" The device has the \"ADIW\" and \"SBIW\" instructions. \"AVRHAVEELPM\" The device has the \"ELPM\" instruction. \"AVRHAVEELPMX\" The device has the \"ELPM Rn,Z\" and \"ELPM Rn,Z+\" instructions. \"AVRHAVELPMX\" The device has the \"LPM Rn,Z\" and \"LPM Rn,Z+\" instructions. \"AVRHAVEMOVW\" The device has the \"MOVW\" instruction to perform 16-bit register-register moves. \"AVRHAVEMUL\" The device has a hardware multiplier. \"AVRHAVEJMPCALL\" The device has the \"JMP\" and \"CALL\" instructions. This is the case for devices with more than 8 KiB of program memory. \"AVRHAVEEIJMPEICALL\" \"AVR3BYTEPC\" The device has the \"EIJMP\" and \"EICALL\" instructions. This is the case for devices with more than 128 KiB of program memory. This also means that the program counter (PC) is 3 bytes wide. \"AVR2BYTEPC\" The program counter (PC) is 2 bytes wide. This is the case for devices with up to 128 KiB of program memory. \"AVRHAVE8BITSP\" \"AVRHAVE16BITSP\" The stack pointer (SP) register is treated as 8-bit respectively 16-bit register by the compiler. The definition of these macros is affected by -mtiny-stack. \"AVRHAVESPH\" \"AVRSP8\" The device has the SPH (high part of stack pointer) special function register or has an 8-bit stack pointer, respectively. The definition of these macros is affected by -mmcu= and in the cases of -mmcu=avr2 and -mmcu=avr25 also by -msp8. \"AVRHAVERAMPD\" \"AVRHAVERAMPX\" \"AVRHAVERAMPY\" \"AVRHAVERAMPZ\" The device has the \"RAMPD\", \"RAMPX\", \"RAMPY\", \"RAMPZ\" special function register, respectively. \"NOINTERRUPTS\" This macro reflects the -mno-interrupts command-line option. \"AVRERRATASKIP\" \"AVRERRATASKIPJMPCALL\" Some AVR devices (AT90S8515, ATmega103) must not skip 32-bit instructions because of a hardware erratum. Skip instructions are \"SBRS\", \"SBRC\", \"SBIS\", \"SBIC\" and \"CPSE\". The second macro is only defined if \"AVRHAVEJMPCALL\" is also set. \"AVRISARMW\" The device has Read-Modify-Write instructions (XCH, LAC, LAS and LAT). \"AVRSFROFFSET=offset\" Instructions that can address I/O special function registers directly like \"IN\", \"OUT\", \"SBI\", etc. may use a different address as if addressed by an instruction to access RAM like \"LD\" or \"STS\". This offset depends on the device architecture and has to be subtracted from the RAM address in order to get the respective I/O address. \"AVRSHORTCALLS\" The -mshort-calls command line option is set. \"AVRPMBASEADDRESS=addr\" Some devices support reading from flash memory by means of \"LD*\" instructions. The flash memory is seen in the data address space at an offset of \"AVRPMBASEADDRESS\". If this macro is not defined, this feature is not available. If defined, the address space is linear and there is no need to put \".rodata\" into RAM. This is handled by the default linker description file, and is currently available for \"avrtiny\" and \"avrxmega3\". Even more convenient, there is no need to use address spaces like \"flash\" or features like attribute \"progmem\" and \"pgmread*\". \"WITHAVRLIBC\" The compiler is configured to be used together with AVR-Libc. See the --with-avrlibc configure option. \"HAVEDOUBLEMULTILIB\" Defined if -mdouble= acts as a multilib option. \"HAVEDOUBLE32\" \"HAVEDOUBLE64\" Defined if the compiler supports 32-bit double resp. 64-bit double. The actual layout is specified by option -mdouble=. \"DEFAULTDOUBLE\" The size in bits of \"double\" if -mdouble= is not set. To test the layout of \"double\" in a program, use the built-in macro \"SIZEOFDOUBLE\". \"HAVELONGDOUBLE32\" \"HAVELONGDOUBLE64\" \"HAVELONGDOUBLEMULTILIB\" \"DEFAULTLONGDOUBLE\" Same as above, but for \"long double\" instead of \"double\". \"WITHDOUBLECOMPARISON\" Reflects the \"--with-double-comparison={tristate|bool|libf7}\" configure option (\"https://gcc.gnu.org/install/configure.html#avr\") and is defined to 2 or 3. \"WITHLIBF7LIBGCC\" \"WITHLIBF7MATH\" \"WITHLIBF7MATHSYMBOLS\" Reflects the \"--with-libf7={libgcc|math|math-symbols}\" configure option (\"https://gcc.gnu.org/install/configure.html#avr\"). AVR Internal Options The following options are used internally by the compiler and to communicate between device specs files and the compiler proper. You don't need to set these options by hand, in particular they are not optimization options. Using these options in the wrong way may lead to sub-optimal or wrong code. They are documented for completeness, and in order to get a better understanding of device specs (\"https://gcc.gnu.org/wiki/avr-gcc#spec-files\") files."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that the flash memory has a size of num times 64 KiB. This determines which \"flashN\" address spaces are available."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that the device supports the Read-Modify-Write instructions \"XCH\", \"LAC\", \"LAS\" and \"LAT\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that \"RJMP\" and \"RCALL\" can target the whole program memory. This option is used for multilib generation and selection for the devices from architecture \"avrxmega3\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code without skips (\"CPSE\", \"SBRS\", \"SBRC\", \"SBIS\", \"SBIC\") over 32-bit instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Treat the stack pointer register as an 8-bit register, i.e. assume the high byte of the stack pointer is zero. This option is used by the compiler to select and build multilibs for architectures \"avr2\" and \"avr25\". These architectures mix devices with and without \"SPH\". Blackfin Options"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies the name of the target Blackfin processor. Currently, cpu can be one of bf512, bf514, bf516, bf518, bf522, bf523, bf524, bf525, bf526, bf527, bf531, bf532, bf533, bf534, bf536, bf537, bf538, bf539, bf542, bf544, bf547, bf548, bf549, bf542m, bf544m, bf547m, bf548m, bf549m, bf561, bf592. The optional sirevision specifies the silicon revision of the target Blackfin processor. Any workarounds available for the targeted silicon revision are enabled. If sirevision is none, no workarounds are enabled. If sirevision is any, all workarounds for the targeted processor are enabled. The \"SILICONREVISION\" macro is defined to two hexadecimal digits representing the major and minor numbers in the silicon revision. If sirevision is none, the \"SILICONREVISION\" is not defined. If sirevision is any, the \"SILICONREVISION\" is defined to be 0xffff. If this optional sirevision is not used, GCC assumes the latest known silicon revision of the targeted Blackfin processor. GCC defines a preprocessor macro for the specified cpu. For the bfin-elf toolchain, this option causes the hardware BSP provided by libgloss to be linked in if -msim is not given. Without this option, bf532 is used as the processor by default. Note that support for bf561 is incomplete. For bf561, only the preprocessor macro is defined."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies that the program will be run on the simulator. This causes the simulator BSP provided by libgloss to be linked in. This option has effect only for bfin-elf toolchain. Certain other options, such as -mid-shared-library and -mfdpic, imply -msim."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't keep the frame pointer in a register for leaf functions. This avoids the instructions to save, set up and restore frame pointers and makes an extra register available in leaf functions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When enabled, the compiler ensures that the generated code does not contain speculative loads after jump instructions. If this option is used, \"WORKAROUNDSPECULATIVELOADS\" is defined."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't generate extra code to prevent speculative loads from occurring."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When enabled, the compiler ensures that the generated code does not contain CSYNC or SSYNC instructions too soon after conditional branches. If this option is used, \"WORKAROUNDSPECULATIVESYNCS\" is defined."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't generate extra code to prevent CSYNC or SSYNC instructions from occurring too soon after a conditional branch."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When enabled, the compiler is free to take advantage of the knowledge that the entire program fits into the low 64k of memory."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that the program is arbitrarily large. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do stack checking using information placed into L1 scratchpad memory by the uClinux kernel."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that supports shared libraries via the library ID method. This allows for execute in place and shared libraries in an environment without virtual memory management. This option implies -fPIC. With a bfin-elf target, this option implies -msim."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that doesn't assume ID-based shared libraries are being used. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that supports shared libraries via the library ID method, but assumes that this library or executable won't link against any other ID shared libraries. That allows the compiler to use faster code for jumps and calls."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not assume that the code being compiled won't link against any ID shared libraries. Slower code is generated for jump and call insns."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies the identification number of the ID-based shared library being compiled. Specifying a value of 0 generates more compact code; specifying other values forces the allocation of that number to the current library but is no more space- or time-efficient than omitting this option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that allows the data segment to be located in a different area of memory from the text segment. This allows for execute in place in an environment without virtual memory management by eliminating relocations against the text section."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that assumes that the data segment follows the text segment. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Tells the compiler to perform function calls by first loading the address of the function into a register and then performing a subroutine call on this register. This switch is needed if the target function lies outside of the 24-bit addressing range of the offset- based version of subroutine call instruction. This feature is not enabled by default. Specifying -mno-long-calls restores the default behavior. Note these switches have no effect on how the compiler generates code to handle function calls via function pointers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Link with the fast floating-point library. This library relaxes some of the IEEE floating-point standard's rules for checking inputs against Not-a-Number (NAN), in the interest of performance."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable inlining of PLT entries in function calls to functions that are not known to bind locally. It has no effect without -mfdpic."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Build a standalone application for multicore Blackfin processors. This option causes proper start files and link scripts supporting multicore to be used, and defines the macro \"BFINMULTICORE\". It can only be used with -mcpu=bf561[-sirevision]. This option can be used with -mcorea or -mcoreb, which selects the one-application-per- core programming model. Without -mcorea or -mcoreb, the single-application/dual-core programming model is used. In this model, the main function of Core B should be named as \"corebmain\". If this option is not used, the single-core application programming model is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Build a standalone application for Core A of BF561 when using the one-application-per- core programming model. Proper start files and link scripts are used to support Core A, and the macro \"BFINCOREA\" is defined. This option can only be used in conjunction with -mmulticore."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Build a standalone application for Core B of BF561 when using the one-application-per- core programming model. Proper start files and link scripts are used to support Core B, and the macro \"BFINCOREB\" is defined. When this option is used, \"corebmain\" should be used instead of \"main\". This option can only be used in conjunction with -mmulticore."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Build a standalone application for SDRAM. Proper start files and link scripts are used to put the application into SDRAM, and the macro \"BFINSDRAM\" is defined. The loader should initialize SDRAM before loading the application."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that ICPLBs are enabled at run time. This has an effect on certain anomaly workarounds. For Linux targets, the default is to assume ICPLBs are enabled; for standalone applications the default is off. C6X Options"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This specifies the name of the target architecture. GCC uses this name to determine what kind of instructions it can emit when generating assembly code. Permissible names are: c62x, c64x, c64x+, c67x, c67x+, c674x."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a big-endian target."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a little-endian target. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Choose startup files and linker script suitable for the simulator."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Put small global and static data in the \".neardata\" section, which is pointed to by register \"B14\". Put small uninitialized global and static data in the \".bss\" section, which is adjacent to the \".neardata\" section. Put small read-only data into the \".rodata\" section. The corresponding sections used for large pieces of data are \".fardata\", \".far\" and \".const\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Put all data, not just small objects, into the sections reserved for small data, and use addressing relative to the \"B14\" register to access them."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Make no use of the sections reserved for small data, and use absolute addresses to access all data. Put all initialized global and static data in the \".fardata\" section, and all uninitialized data in the \".far\" section. Put all constant data into the \".const\" section. CRIS Options These options are defined specifically for the CRIS ports."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the specified architecture. The choices for architecture-type are v3, v8 and v10 for respectively ETRAX 4, ETRAX 100, and ETRAX 100 LX. Default is v0."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Tune to architecture-type everything applicable about the generated code, except for the ABI and the set of available instructions. The choices for architecture-type are the same as for -march=architecture-type."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn when the stack frame of a function exceeds n bytes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The options -metrax4 and -metrax100 are synonyms for -march=v3 and -march=v8 respectively."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Work around a bug in the \"muls\" and \"mulu\" instructions for CPU models where it applies. This option is disabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable CRIS-specific verbose debug-related information in the assembly code. This option also has the effect of turning off the #NOAPP formatted-code indicator to the assembler at the beginning of the assembly file."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use condition-code results from previous instruction; always emit compare and test instructions before use of condition codes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not emit instructions with side effects in addressing modes other than post-increment."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These options (no- options) arrange (eliminate arrangements) for the stack frame, individual data and constants to be aligned for the maximum single data access size for the chosen CPU model. The default is to arrange for 32-bit alignment. ABI details such as structure layout are not affected by these options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Similar to the stack- data- and const-align options above, these options arrange for stack frame, writable data and constants to all be 32-bit, 16-bit or 8-bit aligned. The default is 32-bit alignment."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -mno-prologue-epilogue, the normal function prologue and epilogue which set up the stack frame are omitted and no return instructions or return sequences are generated in the code. Use this option only together with visual inspection of the compiled code: no warnings or errors are generated when call-saved registers must be saved, or storage for local variables needs to be allocated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Legacy no-op option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option arranges to link with input-output functions from a simulator library. Code, initialized data and zero-initialized data are allocated consecutively."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Like -sim, but pass linker options to locate initialized data at 0x40000000 and zero- initialized data at 0x80000000. C-SKY Options GCC supports these options when compiling for C-SKY V2 processors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the C-SKY target architecture. Valid values for arch are: ck801, ck802, ck803, ck807, and ck810. The default is ck810."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the C-SKY target processor. Valid values for cpu are: ck801, ck801t, ck802, ck802t, ck802j, ck803, ck803h, ck803t, ck803ht, ck803f, ck803fh, ck803e, ck803eh, ck803et, ck803eht, ck803ef, ck803efh, ck803ft, ck803eft, ck803efht, ck803r1, ck803hr1, ck803tr1, ck803htr1, ck803fr1, ck803fhr1, ck803er1, ck803ehr1, ck803etr1, ck803ehtr1, ck803efr1, ck803efhr1, ck803ftr1, ck803eftr1, ck803efhtr1, ck803s, ck803st, ck803se, ck803sf, ck803sef, ck803seft, ck807e, ck807ef, ck807, ck807f, ck810e, ck810et, ck810ef, ck810eft, ck810, ck810v, ck810f, ck810t, ck810fv, ck810tv, ck810ft, and ck810ftv."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies which floating-point ABI to use. Permissible values are: soft, softfp and hard. Specifying soft causes GCC to generate output containing library calls for floating-point operations. softfp allows the generation of code using hardware floating-point instructions, but still uses the soft-float calling conventions. hard allows generation of floating-point instructions and uses FPU-specific calling conventions. The default depends on the specific target configuration. Note that the hard-float and soft-float ABIs are not link-compatible; you must compile your entire program with the same ABI, and link with a compatible set of libraries."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select hardware or software floating-point implementations. The default is soft float."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When -mhard-float is in effect, enable generation of double-precision float instructions. This is the default except when compiling for CK803."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When -mhard-float is in effect, enable generation of \"frecipd\", \"fsqrtd\", and \"fdivd\" instructions. This is the default except when compiling for CK803."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select the floating-point processor. This option can only be used with -mhard-float. Values for fpu are fpv2sf (equivalent to -mno-double-float -mno-fdivdu), fpv2 (-mdouble-float -mno-divdu), and fpv2divd (-mdouble-float -mdivdu)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the extended \"lrw\" instruction. This option defaults to on for CK801 and off otherwise."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable interrupt stack instructions; the default is off. The -mistack option is required to handle the \"interrupt\" and \"isr\" function attributes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable multiprocessor instructions; the default is off."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable coprocessor instructions; the default is off."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable coprocessor instructions; the default is off."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable C-SKY security instructions; the default is off."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable C-SKY trust instructions; the default is off."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable C-SKY DSP, Enhanced DSP, or Vector DSP instructions, respectively. All of these options default to off."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate divide instructions. Default is off."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for Smart Mode, using only registers numbered 0-7 to allow use of 16-bit instructions. This option is ignored for CK801 where this is the required behavior, and it defaults to on for CK802. For other targets, the default is off."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code using the high registers numbered 16-31. This option is not supported on CK801, CK802, or CK803, and is enabled by default for other processors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code using global anchor symbol addresses."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code using \"push\" and \"pop\" instructions. This option defaults to on."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code using \"stm\" and \"ldm\" instructions. This option isn't supported on CK801 but is enabled by default on other processors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Create constant pools in the compiler instead of deferring it to the assembler. This option is the default and required for correct code generation on CK801 and CK802, and is optional on other processors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit \".stacksize\" directives for each function in the assembly output. This option defaults to off."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the C-SKY compiler runtime instead of libgcc. This option defaults to off."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the branch costs to roughly \"n\" instructions. The default is 1."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Permit scheduling of function prologue and epilogue sequences. Using this option can result in code that is not compliant with the C-SKY V2 ABI prologue requirements and that cannot be debugged or backtraced. It is disabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Links the library libsemi.a which is in compatible with simulator. Applicable to ELF compiler only. Darwin Options These options are defined for all architectures running the Darwin operating system. FSF GCC on Darwin does not create \"fat\" object files; it creates an object file for the single architecture that GCC was built to target. Apple's GCC on Darwin does create \"fat\" files if multiple -arch options are used; it does so by running the compiler or linker multiple times and joining the results together with lipo. The subtype of the file created (like ppc7400 or ppc970 or i686) is determined by the flags that specify the ISA that GCC is targeting, like -mcpu or -march. The -forcecpusubtypeALL option can be used to override this. The Darwin tools vary in their behavior when presented with an ISA mismatch. The assembler, as, only permits instructions to be used that are valid for the subtype of the file it is generating, so you cannot put 64-bit instructions in a ppc750 object file. The linker for shared libraries, /usr/bin/libtool, fails and prints an error if asked to create a shared library with a less restrictive subtype than its input files (for instance, trying to put a ppc970 object file in a ppc7400 library). The linker for executables, ld, quietly gives the executable the most restrictive subtype of any of its input files."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Add the framework directory dir to the head of the list of directories to be searched for header files. These directories are interleaved with those specified by -I options and are scanned in a left-to-right order. A framework directory is a directory with frameworks in it. A framework is a directory with a Headers and/or PrivateHeaders directory contained directly in it that ends in .framework. The name of a framework is the name of this directory excluding the .framework. Headers associated with the framework are found in one of those two directories, with Headers being searched first. A subframework is a framework directory that is in a framework's Frameworks directory. Includes of subframework headers can only appear in a header of a framework that contains the subframework, or in a sibling subframework header. Two subframeworks are siblings if they occur in the same framework. A subframework should not have the same name as a framework; a warning is issued if this is violated. Currently a subframework cannot have subframeworks; in the future, the mechanism may be extended to support this. The standard frameworks can be found in /System/Library/Frameworks and /Library/Frameworks. An example include looks like \"#include <Framework/header.h>\", where Framework denotes the name of the framework and header.h is found in the PrivateHeaders or Headers directory."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Like -F except the directory is a treated as a system directory. The main difference between this -iframework and -F is that with -iframework the compiler does not warn about constructs contained within header files found via dir. This option is valid only for the C family of languages."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit debugging information for symbols that are used. For stabs debugging format, this enables -feliminate-unused-debug-symbols. This is by default ON."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit debugging information for all symbols and types."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The -fconstant-cfstrings is an alias for -mconstant-cfstrings."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When the NeXT runtime is being used (the default on these systems), override any -fconstant-string-class setting and cause \"@\"...\"\" literals to be laid out as constant CoreFoundation strings."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The earliest version of MacOS X that this executable will run on is version. Typical values supported for version include 12, 10.12, and 10.5.8. If the compiler was built to use the system's headers by default, then the default for this option is the system version on which the compiler is running, otherwise the default is to make choices that are compatible with as many systems and code bases as possible."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable kernel development mode. The -mkernel option sets -static, -fno-common, -fno-use-cxa-atexit, -fno-exceptions, -fno-non-call-exceptions, -fapple-kext, -fno-weak and -fno-rtti where applicable. This mode also sets -mno-altivec, -msoft-float, -fno-builtin and -mlong-branch for PowerPC targets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Override the defaults for \"bool\" so that \"sizeof(bool)==1\". By default sizeof(bool) is 4 when compiling for Darwin/PowerPC and 1 when compiling for Darwin/x86, so this option has no effect on x86. Warning: The -mone-byte-bool switch causes GCC to generate code that is not binary compatible with code generated without that switch. Using this switch may require recompiling all other modules in a program, including system libraries. Use this switch to conform to a non-default data model."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code suitable for fast turnaround development, such as to allow GDB to dynamically load .o files into already-running programs. -findirect-data and -ffix-and-continue are provided for backwards compatibility."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Loads all members of static archive libraries. See man ld(1) for more information."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Cause the errors having to do with files that have the wrong architecture to be fatal."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Causes the output file to be marked such that the dynamic linker will bind all undefined references when the file is loaded or launched."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Produce a Mach-o bundle format file. See man ld(1) for more information."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option specifies the executable that will load the build output file being linked. See man ld(1) for more information."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When passed this option, GCC produces a dynamic library instead of an executable when linking, using the Darwin libtool command."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This causes GCC's output file to have the ALL subtype, instead of one controlled by the -mcpu or -march option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These options are passed to the Darwin linker. The Darwin linker man page describes them in detail. DEC Alpha Options These -m options are defined for the DEC Alpha implementations:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) the hardware floating-point instructions for floating-point operations. When -msoft-float is specified, functions in libgcc.a are used to perform floating-point operations. Unless they are replaced by routines that emulate the floating-point operations, or compiled in such a way as to call such emulations routines, these routines issue floating-point operations. If you are compiling for an Alpha without floating- point operations, you must ensure that the library is built so as not to call them. Note that Alpha implementations without floating-point operations are required to have floating-point registers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses (does not use) the floating-point register set. -mno-fp-regs implies -msoft-float. If the floating-point register set is not used, floating-point operands are passed in integer registers as if they were integers and floating-point results are passed in $0 instead of $f0. This is a non-standard calling sequence, so any function with a floating-point argument or return value called by code compiled with -mno-fp-regs must also be compiled with that option. A typical use of this option is building a kernel that does not use, and hence need not save and restore, any floating-point registers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The Alpha architecture implements floating-point hardware optimized for maximum performance. It is mostly compliant with the IEEE floating-point standard. However, for full compliance, software assistance is required. This option generates code fully IEEE- compliant code except that the inexact-flag is not maintained (see below). If this option is turned on, the preprocessor macro \"IEEEFP\" is defined during compilation. The resulting code is less efficient but is able to correctly support denormalized numbers and exceptional IEEE values such as not-a-number and plus/minus infinity. Other Alpha compilers call this option -ieeewithnoinexact. DEBIAN SPECIFIC: This option is on by default for alpha-linux-gnu, unless -ffinite-math-only (which is part of the -ffast-math set) is specified, because the software functions in the GNU libc math libraries generate denormalized numbers, NaNs, and infs (all of which will cause a programs to SIGFPE when it attempts to use the results without -mieee)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This is like -mieee except the generated code also maintains the IEEE inexact-flag. Turning on this option causes the generated code to implement fully-compliant IEEE math. In addition to \"IEEEFP\", \"IEEEFPEXACT\" is defined as a preprocessor macro. On some Alpha implementations the resulting code may execute significantly slower than the code generated by default. Since there is very little code that depends on the inexact-flag, you should normally not specify this option. Other Alpha compilers call this option -ieeewithinexact."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls what floating-point related traps are enabled. Other Alpha compilers call this option -fptm trap-mode. The trap mode can be set to one of four values: n This is the default (normal) setting. The only traps that are enabled are the ones that cannot be disabled in software (e.g., division by zero trap). u In addition to the traps enabled by n, underflow traps are enabled as well. su Like u, but the instructions are marked to be safe for software completion (see Alpha architecture manual for details). sui Like su, but inexact traps are enabled as well."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Selects the IEEE rounding mode. Other Alpha compilers call this option -fprm rounding- mode. The rounding-mode can be one of: n Normal IEEE rounding mode. Floating-point numbers are rounded towards the nearest machine number or towards the even machine number in case of a tie. m Round towards minus infinity. c Chopped rounding mode. Floating-point numbers are rounded towards zero. d Dynamic rounding mode. A field in the floating-point control register (fpcr, see Alpha architecture reference manual) controls the rounding mode in effect. The C library initializes this register for rounding towards plus infinity. Thus, unless your program modifies the fpcr, d corresponds to round towards plus infinity."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "In the Alpha architecture, floating-point traps are imprecise. This means without software assistance it is impossible to recover from a floating trap and program execution normally needs to be terminated. GCC can generate code that can assist operating system trap handlers in determining the exact location that caused a floating- point trap. Depending on the requirements of an application, different levels of precisions can be selected: p Program precision. This option is the default and means a trap handler can only identify which program caused a floating-point exception. f Function precision. The trap handler can determine the function that caused a floating-point exception. i Instruction precision. The trap handler can determine the exact instruction that caused a floating-point exception. Other Alpha compilers provide the equivalent options called -scopesafe and -resumptionsafe."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option marks the generated code as IEEE conformant. You must not use this option unless you also specify -mtrap-precision=i and either -mfp-trap-mode=su or -mfp-trap-mode=sui. Its only effect is to emit the line .eflag 48 in the function prologue of the generated assembly file."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Normally GCC examines a 32- or 64-bit integer constant to see if it can construct it from smaller constants in two or three instructions. If it cannot, it outputs the constant as a literal and generates code to load it from the data segment at run time. Use this option to require GCC to construct all integer constants using code, even if it takes more instructions (the maximum is six). You typically use this option to build a shared library dynamic loader. Itself a shared library, it must relocate itself in memory before it can find the variables and constants in its own data segment."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Indicate whether GCC should generate code to use the optional BWX, CIX, FIX and MAX instruction sets. The default is to use the instruction sets supported by the CPU type specified via -mcpu= option or that of the CPU on which GCC was built if none is specified."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses (does not use) VAX F and G floating-point arithmetic instead of IEEE single and double precision."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Older Alpha assemblers provided no way to generate symbol relocations except via assembler macros. Use of these macros does not allow optimal instruction scheduling. GNU binutils as of version 2.12 supports a new syntax that allows the compiler to explicitly mark which relocations should apply to which instructions. This option is mostly useful for debugging, as GCC detects the capabilities of the assembler when it is built and sets the default accordingly."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When -mexplicit-relocs is in effect, static data is accessed via gp-relative relocations. When -msmall-data is used, objects 8 bytes long or smaller are placed in a small data area (the \".sdata\" and \".sbss\" sections) and are accessed via 16-bit relocations off of the $gp register. This limits the size of the small data area to 64KB, but allows the variables to be directly accessed via a single instruction. The default is -mlarge-data. With this option the data area is limited to just below 2GB. Programs that require more than 2GB of data must use \"malloc\" or \"mmap\" to allocate the data in the heap instead of in the program's data segment. When generating code for shared libraries, -fpic implies -msmall-data and -fPIC implies -mlarge-data."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When -msmall-text is used, the compiler assumes that the code of the entire program (or shared library) fits in 4MB, and is thus reachable with a branch instruction. When -msmall-data is used, the compiler can assume that all local symbols share the same $gp value, and thus reduce the number of instructions required for a function call from 4 to 1. The default is -mlarge-text."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the instruction set and instruction scheduling parameters for machine type cputype. You can specify either the EV style name or the corresponding chip number. GCC supports scheduling parameters for the EV4, EV5 and EV6 family of processors and chooses the default values for the instruction set from the processor you specify. If you do not specify a processor type, GCC defaults to the processor on which the compiler was built. Supported values for cputype are ev4 ev45 21064 Schedules as an EV4 and has no instruction set extensions. ev5 21164 Schedules as an EV5 and has no instruction set extensions. ev56 21164a Schedules as an EV5 and supports the BWX extension. pca56 21164pc 21164PC Schedules as an EV5 and supports the BWX and MAX extensions. ev6 21264 Schedules as an EV6 and supports the BWX, FIX, and MAX extensions. ev67 21264a Schedules as an EV6 and supports the BWX, CIX, FIX, and MAX extensions. Native toolchains also support the value native, which selects the best architecture option for the host processor. -mcpu=native has no effect if GCC does not recognize the processor."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set only the instruction scheduling parameters for machine type cputype. The instruction set is not changed. Native toolchains also support the value native, which selects the best architecture option for the host processor. -mtune=native has no effect if GCC does not recognize the processor."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Sets the latency the scheduler should assume for typical memory references as seen by the application. This number is highly dependent on the memory access patterns used by the application and the size of the external cache on the machine. Valid options for time are number A decimal number representing clock cycles. L1 L2 L3 main The compiler contains estimates of the number of clock cycles for \"typical\" EV4 & EV5 hardware for the Level 1, 2 & 3 caches (also called Dcache, Scache, and Bcache), as well as to main memory. Note that L3 is only valid for EV5. eBPF Options"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This specifies the hard limit for frame sizes, in bytes. Currently, the value that can be specified should be less than or equal to 32767. Defaults to whatever limit is imposed by the version of the Linux kernel targeted."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This specifies the minimum version of the kernel that will run the compiled program. GCC uses this version to determine which instructions to use, what kernel helpers to allow, etc. Currently, version can be one of 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 4.10, 4.11, 4.12, 4.13, 4.14, 4.15, 4.16, 4.17, 4.18, 4.19, 4.20, 5.0, 5.1, 5.2, latest and native."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a big-endian target."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a little-endian target. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable generation of extra conditional-branch instructions. Enabled for CPU v2 and above."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable 32-bit jump instructions. Enabled for CPU v3 and above."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable 32-bit ALU instructions. Enabled for CPU v3 and above."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This specifies which version of the eBPF ISA to target. Newer versions may not be supported by all kernels. The default is v3. Supported values for version are: v1 The first stable eBPF ISA with no special features or extensions. v2 Supports the jump extensions, as in -mjmpext. v3 All features of v2, plus: -<32-bit jump operations, as in -mjmp32> -<32-bit ALU operations, as in -malu32>"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable BPF Compile Once - Run Everywhere (CO-RE) support. Requires and is implied by -gbtf."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable BPF Compile Once - Run Everywhere (CO-RE) support. BPF CO-RE support is enabled by default when generating BTF debug information for the BPF target."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for an expanded version of BPF, which relaxes some of the restrictions imposed by the BPF architecture: -<Save and restore callee-saved registers at function entry and> exit, respectively. FR30 Options These options are defined specifically for the FR30 port."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use the small address space model. This can produce smaller code, but it does assume that all symbolic values and addresses fit into a 20-bit range."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that runtime support has been provided and so there is no need to include the simulator library (libsim.a) on the linker command line. FT32 Options These options are defined specifically for the FT32 port."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies that the program will be run on the simulator. This causes an alternate runtime startup and library to be linked. You must not use this option when generating programs that will run on real hardware; you must provide your own runtime library for whatever I/O functions are needed."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable Local Register Allocation. This is still experimental for FT32, so by default the compiler uses standard reload."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use div and mod instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable use of the extended instructions of the FT32B processor."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Compress all code using the Ft32B code compression scheme."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not generate code that reads program memory. FRV Options"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Only use the first 32 general-purpose registers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use all 64 general-purpose registers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use only the first 32 floating-point registers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use all 64 floating-point registers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use hardware instructions for floating-point operations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use library routines for floating-point operations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dynamically allocate condition code registers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not try to dynamically allocate condition code registers, only use \"icc0\" and \"fcc0\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Change ABI to use double word insns."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use double word instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use floating-point double instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use floating-point double instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use media instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use media instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use multiply and add/subtract instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use multiply and add/subtract instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select the FDPIC ABI, which uses function descriptors to represent pointers to functions. Without any PIC/PIE-related options, it implies -fPIE. With -fpic or -fpie, it assumes GOT entries and small data are within a 12-bit range from the GOT base address; with -fPIC or -fPIE, GOT offsets are computed with 32 bits. With a bfin-elf target, this option implies -msim."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable inlining of PLT entries in function calls to functions that are not known to bind locally. It has no effect without -mfdpic. It's enabled by default if optimizing for speed and compiling for shared libraries (i.e., -fPIC or -fpic), or when an optimization option such as -O3 or above is present in the command line."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume a large TLS segment when generating thread-local code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not assume a large TLS segment when generating thread-local code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the use of \"GPREL\" relocations in the FDPIC ABI for data that is known to be in read-only sections. It's enabled by default, except for -fpic or -fpie: even though it may help make the global offset table smaller, it trades 1 instruction for 4. With -fPIC or -fPIE, it trades 3 instructions for 4, one of which may be shared by multiple symbols, and it avoids the need for a GOT entry for the referenced symbol, so it's more likely to be a win. If it is not, -mno-gprel-ro can be used to disable it."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Link with the (library, not FD) pic libraries. It's implied by -mlibrary-pic, as well as by -fPIC and -fpic without -mfdpic. You should never have to use it explicitly."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Follow the EABI requirement of always creating a frame pointer whenever a stack frame is allocated. This option is enabled by default and can be disabled with -mno-linked-fp."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use indirect addressing to call functions outside the current compilation unit. This allows the functions to be placed anywhere within the 32-bit address space."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Try to align labels to an 8-byte boundary by inserting NOPs into the previous packet. This option only has an effect when VLIW packing is enabled. It doesn't create new packets; it merely adds NOPs to existing ones."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate position-independent EABI code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use only the first four media accumulator registers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use all eight media accumulator registers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Pack VLIW instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not pack VLIW instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not mark ABI switches in eflags."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the use of conditional-move instructions (default). This switch is mainly for debugging the compiler and will likely be removed in a future version."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable the use of conditional-move instructions. This switch is mainly for debugging the compiler and will likely be removed in a future version."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the use of conditional set instructions (default). This switch is mainly for debugging the compiler and will likely be removed in a future version."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable the use of conditional set instructions. This switch is mainly for debugging the compiler and will likely be removed in a future version."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the use of conditional execution (default). This switch is mainly for debugging the compiler and will likely be removed in a future version."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable the use of conditional execution. This switch is mainly for debugging the compiler and will likely be removed in a future version."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Run a pass to pack branches into VLIW instructions (default). This switch is mainly for debugging the compiler and will likely be removed in a future version."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not run a pass to pack branches into VLIW instructions. This switch is mainly for debugging the compiler and will likely be removed in a future version."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable optimization of \"&&\" and \"||\" in conditional execution (default). This switch is mainly for debugging the compiler and will likely be removed in a future version."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable optimization of \"&&\" and \"||\" in conditional execution. This switch is mainly for debugging the compiler and will likely be removed in a future version."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable nested conditional execution optimizations (default). This switch is mainly for debugging the compiler and will likely be removed in a future version."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable nested conditional execution optimizations. This switch is mainly for debugging the compiler and will likely be removed in a future version."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This switch removes redundant \"membar\" instructions from the compiler-generated code. It is enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This switch disables the automatic removal of redundant \"membar\" instructions from the generated code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Cause gas to print out tomcat statistics."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select the processor type for which to generate code. Possible values are frv, fr550, tomcat, fr500, fr450, fr405, fr400, fr300 and simple. GNU/Linux Options These -m options are defined for GNU/Linux targets:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use the GNU C library. This is the default except on *-*-linux-*uclibc*, *-*-linux-*musl* and *-*-linux-*android* targets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use uClibc C library. This is the default on *-*-linux-*uclibc* targets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use the musl C library. This is the default on *-*-linux-*musl* targets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use Bionic C library. This is the default on *-*-linux-*android* targets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Compile code compatible with Android platform. This is the default on *-*-linux-*android* targets. When compiling, this option enables -mbionic, -fPIC, -fno-exceptions and -fno-rtti by default. When linking, this option makes the GCC driver pass Android-specific options to the linker. Finally, this option causes the preprocessor macro \"ANDROID\" to be defined."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable compilation effects of -mandroid, i.e., do not enable -mbionic, -fPIC, -fno-exceptions and -fno-rtti by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable linking effects of -mandroid, i.e., pass standard Linux linking options to the linker. H8/300 Options These -m options are defined for the H8/300 implementations:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Shorten some address references at link time, when possible; uses the linker option -relax."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "either with -mh or -ms."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the H8S/2600. This switch must be used with -ms."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Extended registers are stored on stack before execution of function with monitor attribute. Default option is -mexr. This option is valid only for H8S targets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Extended registers are not stored on stack before execution of function with monitor attribute. Default option is -mno-exr. This option is valid only for H8S targets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Make \"int\" data 32 bits by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On the H8/300H and H8S, use the same alignment rules as for the H8/300. The default for the H8/300H and H8S is to align longs and floats on 4-byte boundaries. -malign-300 causes them to be aligned on 2-byte boundaries. This option has no effect on the H8/300. HPPA Options These -m options are defined for the HPPA family of computers:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the specified architecture. The choices for architecture-type are 1.0 for PA 1.0, 1.1 for PA 1.1, and 2.0 for PA 2.0 processors. Refer to /usr/lib/sched.models on an HP-UX system to determine the proper architecture option for your machine. Code compiled for lower numbered architectures runs on higher numbered architectures, but not the other way around."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Synonyms for -march=1.0, -march=1.1, and -march=2.0 respectively."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate libcalls for atomic loads and stores when sync libcalls are disabled. This option is enabled by default. It only affects the generation of atomic libcalls by the HPPA backend. Both the sync and libatomic libcall implementations use locking. As a result, processor stores are not atomic with respect to other atomic operations. Processor loads up to DImode are atomic with respect to other atomic operations provided they are implemented as a single access. The PA-RISC architecture does not support any atomic operations in hardware except for the \"ldcw\" instruction. Thus, all atomic support is implemented using sync and atomic libcalls. Sync libcall support is in libgcc.a. Atomic libcall support is in libatomic. This option generates \"atomicexchange\" calls for atomic stores. It also provides special handling for atomic DImode accesses on 32-bit targets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Does nothing. Preserved for backward compatibility."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The caller copies function arguments passed by hidden reference. This option should be used with care as it is not compatible with the default 32-bit runtime. However, only aggregates larger than eight bytes are passed by hidden reference and the option provides better compatibility with OpenMP."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use ldcw/ldcd coherent cache-control hint."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable floating-point registers. Equivalent to \"-msoft-float\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Prevent the compiler from using indexing address modes. This avoids some rather obscure problems when compiling MIG generated code under MACH."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that assumes calls never cross space boundaries. This allows GCC to emit code that performs faster indirect calls. This option does not work in the presence of shared libraries or nested functions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code treating the given register range as fixed registers. A fixed register is one that the register allocator cannot use. This is useful when compiling kernel code. A register range is specified as two registers separated by a dash. Multiple register ranges can be specified separated by a comma."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the use of assembler directives only GAS understands."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use options specific to GNU ld. This passes -shared to ld when building a shared library. It is the default when GCC is configured, explicitly or implicitly, with the GNU linker. This option does not affect which ld is called; it only changes what parameters are passed to that ld. The ld that is called is determined by the --with-ld configure option, GCC's program search path, and finally by the user's PATH. The linker used by GCC can be printed using which `gcc -print-prog-name=ld`. This option is only available on the 64-bit HP-UX GCC, i.e. configured with hppa*64*-*-hpux*."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use options specific to HP ld. This passes -b to ld when building a shared library and passes +Accept TypeMismatch to ld on all links. It is the default when GCC is configured, explicitly or implicitly, with the HP linker. This option does not affect which ld is called; it only changes what parameters are passed to that ld. The ld that is called is determined by the --with-ld configure option, GCC's program search path, and finally by the user's PATH. The linker used by GCC can be printed using which `gcc -print-prog-name=ld`. This option is only available on the 64-bit HP-UX GCC, i.e. configured with hppa*64*-*-hpux*."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the optimization pass in the HP-UX linker. Note this makes symbolic debugging impossible. It also triggers a bug in the HP-UX 8 and HP-UX 9 linkers in which they give bogus error messages when linking some programs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses long call sequences. This ensures that a call is always able to reach linker generated stubs. The default is to generate long calls only when the distance from the call site to the beginning of the function or translation unit, as the case may be, exceeds a predefined limit set by the branch type being used. The limits for normal calls are 7,600,000 and 240,000 bytes, respectively for the PA 2.0 and PA 1.X architectures. Sibcalls are always limited at 240,000 bytes. Distances are measured from the beginning of functions when using the -ffunction-sections option, or when using the -mgas and -mno-portable-runtime options together under HP-UX with the SOM linker. It is normally not desirable to use this option as it degrades performance. However, it may be useful in large applications, particularly when partial linking is used to build the application. The types of long calls used depends on the capabilities of the assembler and linker, and the type of code being generated. The impact on systems that support long absolute calls, and long pic symbol-difference or pc-relative calls should be relatively small. However, an indirect call is used on 32-bit ELF systems in pic code and it is quite long."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate 3-instruction load and store sequences as sometimes required by the HP-UX 10 linker. This is equivalent to the +k option to the HP compilers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is ignored and provided for compatibility purposes only."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that assumes the target has no space registers. This allows GCC to generate faster indirect calls and use unscaled index address modes. Such code is suitable for level 0 PA systems and kernels."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume memory references are ordered and barriers are not needed."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use the portable calling conventions proposed by HP for ELF systems."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Schedule code according to the constraints for the machine type cpu-type. The choices for cpu-type are 700 7100, 7100LC, 7200, 7300 and 8000. Refer to /usr/lib/sched.models on an HP-UX system to determine the proper scheduling option for your machine. The default scheduling is 8000."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate the predefine, \"SIO\", for server IO. The default is -mwsio. This generates the predefines, \"hp9000s700\", \"hp9000s700\" and \"WSIO\", for workstation IO. These options are available under HP-UX and HI-UX."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output containing library calls for floating point. Warning: the requisite libraries are not available for all HPPA targets. Normally the facilities of the machine's usual C compiler are used, but this cannot be done directly in cross- compilation. You must make your own arrangements to provide suitable library functions for cross-compilation. -msoft-float changes the calling convention in the output file; therefore, it is only useful if you compile all of a program with this option. In particular, you need to compile libgcc.a, the library that comes with GCC, with -msoft-float in order for this to work."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use software integer multiplication. This disables the use of the \"xmpyu\" instruction."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate compiler predefines and select a startfile for the specified UNIX standard. The choices for unix-std are 93, 95 and 98. 93 is supported on all HP-UX versions. 95 is available on HP-UX 10.10 and later. 98 is available on HP-UX 11.11 and later. The default values are 93 for HP-UX 10.00, 95 for HP-UX 10.10 though to 11.00, and 98 for HP- UX 11.11 and later. -munix=93 provides the same predefines as GCC 3.3 and 3.4. -munix=95 provides additional predefines for \"XOPENUNIX\" and \"XOPENSOURCEEXTENDED\", and the startfile unix95.o. -munix=98 provides additional predefines for \"XOPENUNIX\", \"XOPENSOURCEEXTENDED\", \"INCLUDESTDCA1SOURCE\" and \"INCLUDEXOPENSOURCE500\", and the startfile unix98.o. It is important to note that this option changes the interfaces for various library routines. It also affects the operational behavior of the C library. Thus, extreme care is needed in using this option. Library code that is intended to operate with more than one UNIX standard must test, set and restore the variable \"xpg4extendedmask\" as appropriate. Most GNU software doesn't provide this capability."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Suppress the generation of link options to search libdld.sl when the -static option is specified on HP-UX 10 and later."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The HP-UX implementation of setlocale in libc has a dependency on libdld.sl. There isn't an archive version of libdld.sl. Thus, when the -static option is specified, special link options are needed to resolve this dependency. On HP-UX 10 and later, the GCC driver adds the necessary options to link with libdld.sl when the -static option is specified. This causes the resulting binary to be dynamic. On the 64-bit port, the linkers generate dynamic binaries by default in any case. The -nolibdld option can be used to prevent the GCC driver from adding these link options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Add support for multithreading with the dce thread library under HP-UX. This option sets flags for both the preprocessor and linker. IA-64 Options These are the -m options defined for the Intel IA-64 architecture."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a big-endian target. This is the default for HP-UX."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a little-endian target. This is the default for AIX5 and GNU/Linux."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (or don't) code for the GNU assembler. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (or don't) code for the GNU linker. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that does not use a global pointer register. The result is not position independent code, and violates the IA-64 ABI."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (or don't) a stop bit immediately before and after volatile asm statements."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (or don't) in, loc, and out register names for the stacked registers. This may make assembler output more readable."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable (or enable) optimizations that use the small data section. This may be useful for working around optimizer bugs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses a single constant global pointer value. This is useful when compiling kernel code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that is self-relocatable. This implies -mconstant-gp. This is useful when compiling firmware code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for inline divides of floating-point values using the minimum latency algorithm."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for inline divides of floating-point values using the maximum throughput algorithm."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not generate inline code for divides of floating-point values."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for inline divides of integer values using the minimum latency algorithm."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for inline divides of integer values using the maximum throughput algorithm."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not generate inline code for divides of integer values."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for inline square roots using the minimum latency algorithm."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for inline square roots using the maximum throughput algorithm."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not generate inline code for \"sqrt\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do (don't) generate code that uses the fused multiply/add or multiply/subtract instructions. The default is to use these instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't (or do) generate assembler code for the DWARF line number debugging info. This may be useful when not using the GNU assembler."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow stop bits to be placed earlier than immediately preceding the instruction that triggered the stop bit. This can improve instruction scheduling, but does not always do so."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code treating the given register range as fixed registers. A fixed register is one that the register allocator cannot use. This is useful when compiling kernel code. A register range is specified as two registers separated by a dash. Multiple register ranges can be specified separated by a comma."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify bit size of immediate TLS offsets. Valid values are 14, 22, and 64."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Tune the instruction scheduling for a particular CPU, Valid values are itanium, itanium1, merced, itanium2, and mckinley."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a 32-bit or 64-bit environment. The 32-bit environment sets int, long and pointer to 32 bits. The 64-bit environment sets int to 32 bits and long and pointer to 64 bits. These are HP-UX specific flags."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "(Dis/En)able data speculative scheduling before reload. This results in generation of \"ld.a\" instructions and the corresponding check instructions (\"ld.c\" / \"chk.a\"). The default setting is disabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "(En/Dis)able data speculative scheduling after reload. This results in generation of \"ld.a\" instructions and the corresponding check instructions (\"ld.c\" / \"chk.a\"). The default setting is enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "(Dis/En)able control speculative scheduling. This feature is available only during region scheduling (i.e. before reload). This results in generation of the \"ld.s\" instructions and the corresponding check instructions \"chk.s\". The default setting is disabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "(En/Dis)able speculative scheduling of the instructions that are dependent on the data speculative loads before reload. This is effective only with -msched-br-data-spec enabled. The default setting is enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "(En/Dis)able speculative scheduling of the instructions that are dependent on the data speculative loads after reload. This is effective only with -msched-ar-data-spec enabled. The default setting is enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "(En/Dis)able speculative scheduling of the instructions that are dependent on the control speculative loads. This is effective only with -msched-control-spec enabled. The default setting is enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If enabled, data-speculative instructions are chosen for schedule only if there are no other choices at the moment. This makes the use of the data speculation much more conservative. The default setting is disabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If enabled, control-speculative instructions are chosen for schedule only if there are no other choices at the moment. This makes the use of the control speculation much more conservative. The default setting is disabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If enabled, speculative dependencies are considered during computation of the instructions priorities. This makes the use of the speculation a bit more conservative. The default setting is disabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use a simple data speculation check. This option is on by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use a simple check for control speculation. This option is on by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Place a stop bit after every cycle when scheduling. This option is on by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that floating-point stores and loads are not likely to cause a conflict when placed into the same instruction group. This option is disabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate checks for control speculation in selective scheduling. This flag is disabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Limit on the number of memory insns per instruction group, giving lower priority to subsequent memory insns attempting to schedule in the same instruction group. Frequently useful to prevent cache bank conflicts. The default value is 1."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Makes the limit specified by msched-max-memory-insns a hard limit, disallowing more than that number in an instruction group. Otherwise, the limit is \"soft\", meaning that non- memory operations are preferred when the limit is reached, but memory operations may still be scheduled. LM32 Options These -m options are defined for the LatticeMico32 architecture:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable barrel-shift instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable divide and modulus instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable multiply instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable sign extend instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable user-defined instructions. LoongArch Options These command-line options are defined for LoongArch targets:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate instructions for the machine type cpu-type. In contrast to -mtune=cpu-type, which merely tunes the generated code for the specified cpu-type, -march=cpu-type allows GCC to generate code that may not run at all on processors other than the one indicated. Specifying -march=cpu-type implies -mtune=cpu-type, except where noted otherwise. The choices for cpu-type are: native This selects the CPU to generate code for at compilation time by determining the processor type of the compiling machine. Using -march=native enables all instruction subsets supported by the local machine (hence the result might not run on different machines). Using -mtune=native produces code optimized for the local machine under the constraints of the selected instruction set. loongarch64 A generic CPU with 64-bit extensions. la464 LoongArch LA464 CPU with LBT, LSX, LASX, LVZ."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Optimize the output for the given processor, specified by microarchitecture name."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the specified calling convention. base-abi-type can be one of: lp64d Uses 64-bit general purpose registers and 32/64-bit floating-point registers for parameter passing. Data model is LP64, where int is 32 bits, while long int and pointers are 64 bits. lp64f Uses 64-bit general purpose registers and 32-bit floating-point registers for parameter passing. Data model is LP64, where int is 32 bits, while long int and pointers are 64 bits. lp64s Uses 64-bit general purpose registers and no floating-point registers for parameter passing. Data model is LP64, where int is 32 bits, while long int and pointers are 64 bits."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the specified FPU type, which can be one of: 64 Allow the use of hardware floating-point instructions for 32-bit and 64-bit operations. 32 Allow the use of hardware floating-point instructions for 32-bit operations. none 0 Prevent the use of hardware floating-point instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force -mfpu=none and prevents the use of floating-point registers for parameter passing. This option may change the target ABI."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force -mfpu=32 and allow the use of 32-bit floating-point registers for parameter passing. This option may change the target ABI."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force -mfpu=64 and allow the use of 32/64-bit floating-point registers for parameter passing. This option may change the target ABI."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the cost of branches to roughly n instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Trap (do not trap) on integer division by zero. The default is -mcheck-zero-division for -O0 or -Og, and -mno-check-zero-division for other optimization levels."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Conditional moves for integral data in general-purpose registers are enabled (disabled). The default is -mcond-move-int."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Conditional moves for floating-point registers are enabled (disabled). The default is -mcond-move-float."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force (do not force) the use of \"memcpy\" for non-trivial block moves. The default is -mno-memcpy, which allows GCC to inline most constant-sized copies. Setting optimization level to -Os also forces the use of \"memcpy\", but -mno-memcpy may override this behavior if explicitly specified, regardless of the order these options on the command line."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Avoid or allow generating memory accesses that may not be aligned on a natural object boundary as described in the architecture specification. The default is -mno-strict-align."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Put global and static data smaller than number bytes into a special section (on some targets). The default value is 0."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Inline all block moves (such as calls to \"memcpy\" or structure copies) less than or equal to n bytes. The default value of n is 1024."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the code model to one of: tiny-static (Not implemented yet) tiny (Not implemented yet) normal The text segment must be within 128MB addressing space. The data segment must be within 2GB addressing space. medium The text segment and data segment must be within 2GB addressing space. large (Not implemented yet) extreme This mode does not limit the size of the code segment and data segment. The -mcmodel=extreme option is incompatible with -fplt and -mno-explicit-relocs. The default code model is \"normal\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use or do not use assembler relocation operators when dealing with symbolic addresses. The alternative is to use assembler macros instead, which may limit instruction scheduling but allow linker relaxation. The default value for the option is determined with the assembler capability detected during GCC build-time and the setting of \"-mrelax\": \"-mexplicit-relocs\" if the assembler supports relocation operators but \"-mrelax\" is not enabled, \"-mno-explicit-relocs\" otherwise."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use or use GOT to access external symbols. The default is -mno-direct-extern-access: GOT is used for external symbols with default visibility, but not used for other external symbols. With -mdirect-extern-access, GOT is not used and all external symbols are PC-relatively addressed. It is only suitable for environments where no dynamic link is performed, like firmwares, OS kernels, executables linked with -static or -static-pie. -mdirect-extern-access is not compatible with -fPIC or -fpic."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Take (do not take) advantage of linker relaxations. If -mpass-mrelax-to-as is enabled, this option is also passed to the assembler. The default is determined during GCC build- time by detecting corresponding assembler support: -mrelax if the assembler supports both the -mrelax option and the conditional branch relaxation (it's required or the \".align\" directives and conditional branch instructions in the assembly code outputted by GCC may be rejected by the assembler because of a relocation overflow), -mno-relax otherwise."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Pass (do not pass) the -mrelax or -mno-relax option to the assembler. The default is determined during GCC build-time by detecting corresponding assembler support: -mpass-mrelax-to-as if the assembler supports the -mrelax option, -mno-pass-mrelax-to-as otherwise. This option is mostly useful for debugging, or interoperation with assemblers different from the build-time one. M32C Options"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select the CPU for which code is generated. name may be one of r8c for the R8C/Tiny series, m16c for the M16C (up to /60) series, m32cm for the M16C/80 series, or m32c for the M32C/80 series."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies that the program will be run on the simulator. This causes an alternate runtime library to be linked in which supports, for example, file I/O. You must not use this option when generating programs that will run on real hardware; you must provide your own runtime library for whatever I/O functions are needed."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies the number of memory-based pseudo-registers GCC uses during code generation. These pseudo-registers are used like real registers, so there is a tradeoff between GCC's ability to fit the code into available registers, and the performance penalty of using memory instead of registers. Note that all modules in a program must be compiled with the same value for this option. Because of that, you must not use this option with GCC's default runtime libraries. M32R/D Options These -m options are defined for Renesas M32R/D architectures:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the M32R/2."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the M32R/X."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the M32R. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume all objects live in the lower 16MB of memory (so that their addresses can be loaded with the \"ld24\" instruction), and assume all subroutines are reachable with the \"bl\" instruction. This is the default. The addressability of a particular object can be set with the \"model\" attribute."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume objects may be anywhere in the 32-bit address space (the compiler generates \"seth/add3\" instructions to load their addresses), and assume all subroutines are reachable with the \"bl\" instruction."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume objects may be anywhere in the 32-bit address space (the compiler generates \"seth/add3\" instructions to load their addresses), and assume subroutines may not be reachable with the \"bl\" instruction (the compiler generates the much slower \"seth/add3/jl\" instruction sequence)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable use of the small data area. Variables are put into one of \".data\", \".bss\", or \".rodata\" (unless the \"section\" attribute has been specified). This is the default. The small data area consists of sections \".sdata\" and \".sbss\". Objects may be explicitly put in the small data area with the \"section\" attribute using one of these sections."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Put small global and static data in the small data area, but do not generate special code to reference them."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Put small global and static data in the small data area, and generate special instructions to reference them."
        },
        {
            "flag": "-G",
            "long": null,
            "arg": null,
            "description": "Put global and static objects less than or equal to num bytes into the small data or BSS sections instead of the normal data or BSS sections. The default value of num is 8. The -msdata option must be set to one of sdata or use for this option to have any effect. All modules should be compiled with the same -G num value. Compiling with different values of num may or may not work; if it doesn't the linker gives an error message---incorrect code is not generated."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Makes the M32R-specific code in the compiler display some statistics that might help in debugging programs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Align all loops to a 32-byte boundary."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not enforce a 32-byte alignment for loops. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Issue number instructions per cycle. number can only be 1 or 2."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "number can only be 1 or 2. If it is 1 then branches are preferred over conditional code, if it is 2, then the opposite applies."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies the trap number to use to flush the cache. The default is 12. Valid numbers are between 0 and 15 inclusive."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies that the cache cannot be flushed by using a trap."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies the name of the operating system function to call to flush the cache. The default is flushcache, but a function call is only used if a trap is not available."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Indicates that there is no OS function for flushing the cache. M680x0 Options These are the -m options defined for M680x0 and ColdFire processors. The default settings depend on which architecture was selected when the compiler was configured; the defaults for the most common choices are given below."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a specific M680x0 or ColdFire instruction set architecture. Permissible values of arch for M680x0 architectures are: 68000, 68010, 68020, 68030, 68040, 68060 and cpu32. ColdFire architectures are selected according to Freescale's ISA classification and the permissible values are: isaa, isaaplus, isab and isac. GCC defines a macro \"mcfarch\" whenever it is generating code for a ColdFire target. The arch in this macro is one of the -march arguments given above. When used together, -march and -mtune select code that runs on a family of similar processors but that is optimized for a particular microarchitecture."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a specific M680x0 or ColdFire processor. The M680x0 cpus are: 68000, 68010, 68020, 68030, 68040, 68060, 68302, 68332 and cpu32. The ColdFire cpus are given by the table below, which also classifies the CPUs into families: Family : -mcpu arguments 51 : 51 51ac 51ag 51cn 51em 51je 51jf 51jg 51jm 51mm 51qe 51qm 5206 : 5202 5204 5206 5206e : 5206e 5208 : 5207 5208 5211a : 5210a 5211a 5213 : 5211 5212 5213 5216 : 5214 5216 52235 : 52230 52231 52232 52233 52234 52235 5225 : 5224 5225 52259 : 52252 52254 52255 52256 52258 52259 5235 : 5232 5233 5234 5235 523x 5249 : 5249 5250 : 5250 5271 : 5270 5271 5272 : 5272 5275 : 5274 5275 5282 : 5280 5281 5282 528x 53017 : 53011 53012 53013 53014 53015 53016 53017 5307 : 5307 5329 : 5327 5328 5329 532x 5373 : 5372 5373 537x 5407 : 5407 5475 : 5470 5471 5472 5473 5474 5475 547x 5480 5481 5482 5483 5484 5485 -mcpu=cpu overrides -march=arch if arch is compatible with cpu. Other combinations of -mcpu and -march are rejected. GCC defines the macro \"mcfcpucpu\" when ColdFire target cpu is selected. It also defines \"mcffamilyfamily\", where the value of family is given by the table above."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Tune the code for a particular microarchitecture within the constraints set by -march and -mcpu. The M680x0 microarchitectures are: 68000, 68010, 68020, 68030, 68040, 68060 and cpu32. The ColdFire microarchitectures are: cfv1, cfv2, cfv3, cfv4 and cfv4e. You can also use -mtune=68020-40 for code that needs to run relatively well on 68020, 68030 and 68040 targets. -mtune=68020-60 is similar but includes 68060 targets as well. These two options select the same tuning decisions as -m68020-40 and -m68020-60 respectively. GCC defines the macros \"mcarch\" and \"mcarch\" when tuning for 680x0 architecture arch. It also defines \"mcarch\" unless either -ansi or a non-GNU -std option is used. If GCC is tuning for a range of architectures, as selected by -mtune=68020-40 or -mtune=68020-60, it defines the macros for every architecture in the range. GCC also defines the macro \"muarch\" when tuning for ColdFire microarchitecture uarch, where uarch is one of the arguments given above."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output for a 68000. This is the default when the compiler is configured for 68000-based systems. It is equivalent to -march=68000. Use this option for microcontrollers with a 68000 or EC000 core, including the 68008, 68302, 68306, 68307, 68322, 68328 and 68356."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output for a 68010. This is the default when the compiler is configured for 68010-based systems. It is equivalent to -march=68010."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output for a 68020. This is the default when the compiler is configured for 68020-based systems. It is equivalent to -march=68020."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output for a 68030. This is the default when the compiler is configured for 68030-based systems. It is equivalent to -march=68030."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output for a 68040. This is the default when the compiler is configured for 68040-based systems. It is equivalent to -march=68040. This option inhibits the use of 68881/68882 instructions that have to be emulated by software on the 68040. Use this option if your 68040 does not have code to emulate those instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output for a 68060. This is the default when the compiler is configured for 68060-based systems. It is equivalent to -march=68060. This option inhibits the use of 68020 and 68881/68882 instructions that have to be emulated by software on the 68060. Use this option if your 68060 does not have code to emulate those instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output for a CPU32. This is the default when the compiler is configured for CPU32-based systems. It is equivalent to -march=cpu32. Use this option for microcontrollers with a CPU32 or CPU32+ core, including the 68330, 68331, 68332, 68333, 68334, 68336, 68340, 68341, 68349 and 68360."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output for a 520X ColdFire CPU. This is the default when the compiler is configured for 520X-based systems. It is equivalent to -mcpu=5206, and is now deprecated in favor of that option. Use this option for microcontroller with a 5200 core, including the MCF5202, MCF5203, MCF5204 and MCF5206."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output for a 5206e ColdFire CPU. The option is now deprecated in favor of the equivalent -mcpu=5206e."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output for a member of the ColdFire 528X family. The option is now deprecated in favor of the equivalent -mcpu=528x."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output for a ColdFire 5307 CPU. The option is now deprecated in favor of the equivalent -mcpu=5307."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output for a ColdFire 5407 CPU. The option is now deprecated in favor of the equivalent -mcpu=5407."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output for a ColdFire V4e family CPU (e.g. 547x/548x). This includes use of hardware floating-point instructions. The option is equivalent to -mcpu=547x, and is now deprecated in favor of that option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output for a 68040, without using any of the new instructions. This results in code that can run relatively efficiently on either a 68020/68881 or a 68030 or a 68040. The generated code does use the 68881 instructions that are emulated on the 68040. The option is equivalent to -march=68020 -mtune=68020-40."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output for a 68060, without using any of the new instructions. This results in code that can run relatively efficiently on either a 68020/68881 or a 68030 or a 68040. The generated code does use the 68881 instructions that are emulated on the 68060. The option is equivalent to -march=68020 -mtune=68020-60."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate floating-point instructions. This is the default for 68020 and above, and for ColdFire devices that have an FPU. It defines the macro \"HAVE68881\" on M680x0 targets and \"mcffpu\" on ColdFire targets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not generate floating-point instructions; use library calls instead. This is the default for 68000, 68010, and 68832 targets. It is also the default for ColdFire devices that have no FPU."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) ColdFire hardware divide and remainder instructions. If -march is used without -mcpu, the default is \"on\" for ColdFire architectures and \"off\" for M680x0 architectures. Otherwise, the default is taken from the target CPU (either the default CPU, or the one specified by -mcpu). For example, the default is \"off\" for -mcpu=5206 and \"on\" for -mcpu=5206e. GCC defines the macro \"mcfhwdiv\" when this option is enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Consider type \"int\" to be 16 bits wide, like \"short int\". Additionally, parameters passed on the stack are also aligned to a 16-bit boundary even on targets whose API mandates promotion to 32-bit."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not consider type \"int\" to be 16 bits wide. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use the bit-field instructions. The -m68000, -mcpu32 and -m5200 options imply -mnobitfield."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do use the bit-field instructions. The -m68020 option implies -mbitfield. This is the default if you use a configuration designed for a 68020."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use a different function-calling convention, in which functions that take a fixed number of arguments return with the \"rtd\" instruction, which pops their arguments while returning. This saves one instruction in the caller since there is no need to pop the arguments there. This calling convention is incompatible with the one normally used on Unix, so you cannot use it if you need to call libraries compiled with the Unix compiler. Also, you must provide function prototypes for all functions that take variable numbers of arguments (including \"printf\"); otherwise incorrect code is generated for calls to those functions. In addition, seriously incorrect code results if you call a function with too many arguments. (Normally, extra arguments are harmlessly ignored.) The \"rtd\" instruction is supported by the 68010, 68020, 68030, 68040, 68060 and CPU32 processors, but not by the 68000 or 5200. The default is -mno-rtd."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Control whether GCC aligns \"int\", \"long\", \"long long\", \"float\", \"double\", and \"long double\" variables on a 32-bit boundary (-malign-int) or a 16-bit boundary (-mno-align-int). Aligning variables on 32-bit boundaries produces code that runs somewhat faster on processors with 32-bit busses at the expense of more memory. Warning: if you use the -malign-int switch, GCC aligns structures containing the above types differently than most published application binary interface specifications for the m68k. Use the pc-relative addressing mode of the 68000 directly, instead of using a global offset table. At present, this option implies -fpic, allowing at most a 16-bit offset for pc-relative addressing. -fPIC is not presently supported with -mpcrel, though this could be supported for 68020 and higher processors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not (do) assume that unaligned memory references are handled by the system."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that allows the data segment to be located in a different area of memory from the text segment. This allows for execute-in-place in an environment without virtual memory management. This option implies -fPIC."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that assumes that the data segment follows the text segment. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that supports shared libraries via the library ID method. This allows for execute-in-place and shared libraries in an environment without virtual memory management. This option implies -fPIC."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that doesn't assume ID-based shared libraries are being used. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies the identification number of the ID-based shared library being compiled. Specifying a value of 0 generates more compact code; specifying other values forces the allocation of that number to the current library, but is no more space- or time-efficient than omitting this option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When generating position-independent code for ColdFire, generate code that works if the GOT has more than 8192 entries. This code is larger and slower than code generated without this option. On M680x0 processors, this option is not needed; -fPIC suffices. GCC normally uses a single instruction to load values from the GOT. While this is relatively efficient, it only works if the GOT is smaller than about 64k. Anything larger causes the linker to report an error such as: relocation truncated to fit: R68KGOT16O foobar If this happens, you should recompile your code with -mxgot. It should then work with very large GOTs. However, code generated with -mxgot is less efficient, since it takes 4 instructions to fetch the value of a global symbol. Note that some linkers, including newer versions of the GNU linker, can create multiple GOTs and sort GOT entries. If you have such a linker, you should only need to use -mxgot when compiling a single object file that accesses more than 8192 GOT entries. Very few do. These options have no effect unless GCC is generating position-independent code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use 32-bit offsets in \"switch\" tables. The default is to use 16-bit offsets. MCore Options These are the -m options defined for the Motorola M*Core processors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Inline constants into the code stream if it can be done in two instructions or less."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use the divide instruction. (Enabled by default)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow arbitrary-sized immediates in bit operations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Always treat bit-fields as \"int\"-sized."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force all functions to be aligned to a 4-byte boundary."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit callgraph information."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Prefer word access when reading byte quantities."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a little-endian target."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the 210 processor."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that runtime support has been provided and so omit the simulator library (libsim.a) from the linker command line."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the maximum amount for a single stack increment operation. Large values can increase the speed of programs that contain functions that need a large amount of stack space, but they can also trigger a segmentation fault if the stack is extended too much. The default value is 0x1000. MicroBlaze Options"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use software emulation for floating point (default)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use hardware floating-point instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not optimize block moves, use \"memcpy\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is deprecated. Use -fno-zero-initialized-in-bss instead."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use features of, and schedule code for, the given CPU. Supported values are in the format vX.YY.Z, where X is a major version, YY is the minor version, and Z is compatibility code. Example values are v3.00.a, v4.00.b, v5.00.a, v5.00.b, v6.00.a."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use software multiply emulation (default)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use software emulation for divides (default)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use the hardware barrel shifter."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use pattern compare instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use table lookup optimization for small signed integer divisions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is deprecated. Use -fstack-check instead."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use GP-relative \".sdata\"/\".sbss\" sections."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use multiply high instructions for high part of 32x32 multiply."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use hardware floating-point conversion instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use hardware floating-point square root instruction."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a big-endian target."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a little-endian target."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use reorder instructions (swap and byte reversed load/store)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select application model app-model. Valid models are executable normal executable (default), uses startup code crt0.o. xmdstub for use with Xilinx Microprocessor Debugger (XMD) based software intrusive debug agent called xmdstub. This uses startup file crt1.o and sets the start address of the program to 0x800. bootstrap for applications that are loaded using a bootloader. This model uses startup file crt2.o which does not contain a processor reset vector handler. This is suitable for transferring control on a processor reset to the bootloader rather than the application. novectors for applications that do not require any of the MicroBlaze vectors. This option may be useful for applications running within a monitoring application. This model uses crt3.o as a startup file. Option -xl-mode-app-model is a deprecated alias for -mxl-mode-app-model."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that the displacement between the text and data segments is fixed at static link time. This allows data to be referenced by offset from start of text address instead of GOT since PC-relative addressing is not supported. MIPS Options"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that runs on arch, which can be the name of a generic MIPS ISA, or the name of a particular processor. The ISA names are: mips1, mips2, mips3, mips4, mips32, mips32r2, mips32r3, mips32r5, mips32r6, mips64, mips64r2, mips64r3, mips64r5 and mips64r6. The processor names are: 4kc, 4km, 4kp, 4ksc, 4kec, 4kem, 4kep, 4ksd, 5kc, 5kf, 20kc, 24kc, 24kf21, 24kf11, 24kec, 24kef21, 24kef11, 34kc, 34kf21, 34kf11, 34kn, 74kc, 74kf21, 74kf11, 74kf32, 1004kc, 1004kf21, 1004kf11, i6400, i6500, interaptiv, loongson2e, loongson2f, loongson3a, gs464, gs464e, gs264e, m4k, m14k, m14kc, m14ke, m14kec, m5100, m5101, octeon, octeon+, octeon2, octeon3, orion, p5600, p6600, r2000, r3000, r3900, r4000, r4400, r4600, r4650, r4700, r5900, r6000, r8000, rm7000, rm9000, r10000, r12000, r14000, r16000, sb1, sr71000, vr4100, vr4111, vr4120, vr4130, vr4300, vr5000, vr5400, vr5500, xlr and xlp. The special value from-abi selects the most compatible architecture for the selected ABI (that is, mips1 for 32-bit ABIs and mips3 for 64-bit ABIs). The native Linux/GNU toolchain also supports the value native, which selects the best architecture option for the host processor. -march=native has no effect if GCC does not recognize the processor. In processor names, a final 000 can be abbreviated as k (for example, -march=r2k). Prefixes are optional, and vr may be written r. Names of the form nf21 refer to processors with FPUs clocked at half the rate of the core, names of the form nf11 refer to processors with FPUs clocked at the same rate as the core, and names of the form nf32 refer to processors with FPUs clocked a ratio of 3:2 with respect to the core. For compatibility reasons, nf is accepted as a synonym for nf21 while nx and bfx are accepted as synonyms for nf11. GCC defines two macros based on the value of this option. The first is \"MIPSARCH\", which gives the name of target architecture, as a string. The second has the form \"MIPSARCHfoo\", where foo is the capitalized value of \"MIPSARCH\". For example, -march=r2000 sets \"MIPSARCH\" to \"r2000\" and defines the macro \"MIPSARCHR2000\". Note that the \"MIPSARCH\" macro uses the processor names given above. In other words, it has the full prefix and does not abbreviate 000 as k. In the case of from-abi, the macro names the resolved architecture (either \"mips1\" or \"mips3\"). It names the default architecture when no -march option is given."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Optimize for arch. Among other things, this option controls the way instructions are scheduled, and the perceived cost of arithmetic operations. The list of arch values is the same as for -march. When this option is not used, GCC optimizes for the processor specified by -march. By using -march and -mtune together, it is possible to generate code that runs on a family of processors, but optimize the code for one particular member of that family. -mtune defines the macros \"MIPSTUNE\" and \"MIPSTUNEfoo\", which work in the same way as the -march ones described above."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Equivalent to -march=mips1."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Equivalent to -march=mips2."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Equivalent to -march=mips3."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Equivalent to -march=mips4."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Equivalent to -march=mips32."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Equivalent to -march=mips32r3."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Equivalent to -march=mips32r5."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Equivalent to -march=mips32r6."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Equivalent to -march=mips64."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Equivalent to -march=mips64r2."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Equivalent to -march=mips64r3."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Equivalent to -march=mips64r5."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Equivalent to -march=mips64r6."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) MIPS16 code. If GCC is targeting a MIPS32 or MIPS64 architecture, it makes use of the MIPS16e ASE. MIPS16 code generation can also be controlled on a per-function basis by means of \"mips16\" and \"nomips16\" attributes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate MIPS16 code on alternating functions. This option is provided for regression testing of mixed MIPS16/non-MIPS16 code generation, and is not intended for ordinary use in compiling user code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Require (do not require) that code using the standard (uncompressed) MIPS ISA be link- compatible with MIPS16 and microMIPS code, and vice versa. For example, code using the standard ISA encoding cannot jump directly to MIPS16 or microMIPS code; it must either use a call or an indirect jump. -minterlink-compressed therefore disables direct jumps unless GCC knows that the target of the jump is not compressed."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Aliases of -minterlink-compressed and -mno-interlink-compressed. These options predate the microMIPS ASE and are retained for backwards compatibility."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the given ABI. Note that the EABI has a 32-bit and a 64-bit variant. GCC normally generates 64-bit code when you select a 64-bit architecture, but you can use -mgp32 to get 32-bit code instead. For information about the O64 ABI, see <https://gcc.gnu.org/projects/mipso64-abi.html>. GCC supports a variant of the o32 ABI in which floating-point registers are 64 rather than 32 bits wide. You can select this combination with -mabi=32 -mfp64. This ABI relies on the \"mthc1\" and \"mfhc1\" instructions and is therefore only supported for MIPS32R2, MIPS32R3 and MIPS32R5 processors. The register assignments for arguments and return values remain the same, but each scalar value is passed in a single 64-bit register rather than a pair of 32-bit registers. For example, scalar floating-point values are returned in $f0 only, not a $f0/$f1 pair. The set of call-saved registers also remains the same in that the even-numbered double- precision registers are saved. Two additional variants of the o32 ABI are supported to enable a transition from 32-bit to 64-bit registers. These are FPXX (-mfpxx) and FP64A (-mfp64 -mno-odd-spreg). The FPXX extension mandates that all code must execute correctly when run using 32-bit or 64-bit registers. The code can be interlinked with either FP32 or FP64, but not both. The FP64A extension is similar to the FP64 extension but forbids the use of odd-numbered single-precision registers. This can be used in conjunction with the \"FRE\" mode of FPUs in MIPS32R5 processors and allows both FP32 and FP64A code to interlink and run in the same process without changing FPU modes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) code that is suitable for SVR4-style dynamic objects. -mabicalls is the default for SVR4-based systems."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) code that is fully position-independent, and that can therefore be linked into shared libraries. This option only affects -mabicalls. All -mabicalls code has traditionally been position-independent, regardless of options like -fPIC and -fpic. However, as an extension, the GNU toolchain allows executables to use absolute accesses for locally-binding symbols. It can also use shorter GP initialization sequences and generate direct calls to locally-defined functions. This mode is selected by -mno-shared. -mno-shared depends on binutils 2.16 or higher and generates objects that can only be linked by the GNU linker. However, the option does not affect the ABI of the final executable; it only affects the ABI of relocatable objects. Using -mno-shared generally makes executables both smaller and quicker. -mshared is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume (do not assume) that the static and dynamic linkers support PLTs and copy relocations. This option only affects -mno-shared -mabicalls. For the n64 ABI, this option has no effect without -msym32. You can make -mplt the default by configuring GCC with --with-mips-plt. The default is -mno-plt otherwise."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Lift (do not lift) the usual restrictions on the size of the global offset table. GCC normally uses a single instruction to load values from the GOT. While this is relatively efficient, it only works if the GOT is smaller than about 64k. Anything larger causes the linker to report an error such as: relocation truncated to fit: RMIPSGOT16 foobar If this happens, you should recompile your code with -mxgot. This works with very large GOTs, although the code is also less efficient, since it takes three instructions to fetch the value of a global symbol. Note that some linkers can create multiple GOTs. If you have such a linker, you should only need to use -mxgot when a single object file accesses more than 64k's worth of GOT entries. Very few do. These options have no effect unless GCC is generating position independent code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that general-purpose registers are 32 bits wide."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that general-purpose registers are 64 bits wide."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that floating-point registers are 32 bits wide."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that floating-point registers are 64 bits wide."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not assume the width of floating-point registers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use floating-point coprocessor instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use floating-point coprocessor instructions. Implement floating-point calculations using library calls instead."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Equivalent to -msoft-float, but additionally asserts that the program being compiled does not perform any floating-point operations. This option is presently supported only by some bare-metal MIPS configurations, where it may select a special set of libraries that lack all floating-point support (including, for example, the floating-point \"printf\" formats). If code compiled with -mno-float accidentally contains floating-point operations, it is likely to suffer a link-time or run-time failure."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that the floating-point coprocessor only supports single-precision operations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that the floating-point coprocessor supports double-precision operations. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the use of odd-numbered single-precision floating-point registers for the o32 ABI. This is the default for processors that are known to support these registers. When using the o32 FPXX ABI, -mno-odd-spreg is set by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These options control the treatment of the special not-a-number (NaN) IEEE 754 floating- point data with the \"abs.fmt\" and \"neg.fmt\" machine instructions. By default or when -mabs=legacy is used the legacy treatment is selected. In this case these instructions are considered arithmetic and avoided where correct operation is required and the input operand might be a NaN. A longer sequence of instructions that manipulate the sign bit of floating-point datum manually is used instead unless the -ffinite-math-only option has also been specified. The -mabs=2008 option selects the IEEE 754-2008 treatment. In this case these instructions are considered non-arithmetic and therefore operating correctly in all cases, including in particular where the input operand is a NaN. These instructions are therefore always used for the respective operations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These options control the encoding of the special not-a-number (NaN) IEEE 754 floating- point data. The -mnan=legacy option selects the legacy encoding. In this case quiet NaNs (qNaNs) are denoted by the first bit of their trailing significand field being 0, whereas signaling NaNs (sNaNs) are denoted by the first bit of their trailing significand field being 1. The -mnan=2008 option selects the IEEE 754-2008 encoding. In this case qNaNs are denoted by the first bit of their trailing significand field being 1, whereas sNaNs are denoted by the first bit of their trailing significand field being 0. The default is -mnan=legacy unless GCC has been configured with --with-nan=2008."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) ll, sc, and sync instructions to implement atomic memory built-in functions. When neither option is specified, GCC uses the instructions if the target architecture supports them. -mllsc is useful if the runtime environment can emulate the instructions and -mno-llsc can be useful when compiling for nonstandard ISAs. You can make either option the default by configuring GCC with --with-llsc and --without-llsc respectively. --with-llsc is the default for some configurations; see the installation documentation for details."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) revision 1 of the MIPS DSP ASE. This option defines the preprocessor macro \"mipsdsp\". It also defines \"mipsdsprev\" to 1."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) revision 2 of the MIPS DSP ASE. This option defines the preprocessor macros \"mipsdsp\" and \"mipsdspr2\". It also defines \"mipsdsprev\" to 2."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) the MIPS SmartMIPS ASE."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) paired-single floating-point instructions. This option requires hardware floating-point support to be enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) MIPS Digital Media Extension instructions. This option can only be used when generating 64-bit code and requires hardware floating-point support to be enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) the MIPS-3D ASE. The option -mips3d implies -mpaired-single."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) microMIPS code. MicroMIPS code generation can also be controlled on a per-function basis by means of \"micromips\" and \"nomicromips\" attributes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) MT Multithreading instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) the MIPS MCU ASE instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) the MIPS Enhanced Virtual Addressing instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) the MIPS Virtualization (VZ) instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) the MIPS eXtended Physical Address (XPA) instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) the MIPS Cyclic Redundancy Check (CRC) instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) the MIPS Global INValidate (GINV) instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) the MIPS Loongson MultiMedia extensions Instructions (MMI)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) the MIPS Loongson EXTensions (EXT) instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) the MIPS Loongson EXTensions r2 (EXT2) instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force \"long\" types to be 64 bits wide. See -mlong32 for an explanation of the default and the way that the pointer size is determined."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force \"long\", \"int\", and pointer types to be 32 bits wide. The default size of \"int\"s, \"long\"s and pointers depends on the ABI. All the supported ABIs use 32-bit \"int\"s. The n64 ABI uses 64-bit \"long\"s, as does the 64-bit EABI; the others use 32-bit \"long\"s. Pointers are the same size as \"long\"s, or the same size as integer registers, whichever is smaller."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume (do not assume) that all symbols have 32-bit values, regardless of the selected ABI. This option is useful in combination with -mabi=64 and -mno-abicalls because it allows GCC to generate shorter and faster references to symbolic addresses."
        },
        {
            "flag": "-G",
            "long": null,
            "arg": null,
            "description": "Put definitions of externally-visible data in a small data section if that data is no bigger than num bytes. GCC can then generate more efficient accesses to the data; see -mgpopt for details. The default -G option depends on the configuration."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Extend (do not extend) the -G behavior to local data too, such as to static variables in C. -mlocal-sdata is the default for all configurations. If the linker complains that an application is using too much small data, you might want to try rebuilding the less performance-critical parts with -mno-local-sdata. You might also want to build large libraries with -mno-local-sdata, so that the libraries leave more room for the main program."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume (do not assume) that externally-defined data is in a small data section if the size of that data is within the -G limit. -mextern-sdata is the default for all configurations. If you compile a module Mod with -mextern-sdata -G num -mgpopt, and Mod references a variable Var that is no bigger than num bytes, you must make sure that Var is placed in a small data section. If Var is defined by another module, you must either compile that module with a high-enough -G setting or attach a \"section\" attribute to Var's definition. If Var is common, you must link the application with a high-enough -G setting. The easiest way of satisfying these restrictions is to compile and link every module with the same -G option. However, you may wish to build a library that supports several different small data limits. You can do this by compiling the library with the highest supported -G setting and additionally using -mno-extern-sdata to stop the library from making assumptions about externally-defined data."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) GP-relative accesses for symbols that are known to be in a small data section; see -G, -mlocal-sdata and -mextern-sdata. -mgpopt is the default for all configurations. -mno-gpopt is useful for cases where the $gp register might not hold the value of \"gp\". For example, if the code is part of a library that might be used in a boot monitor, programs that call boot monitor routines pass an unknown value in $gp. (In such situations, the boot monitor itself is usually compiled with -G0.) -mno-gpopt implies -mno-local-sdata and -mno-extern-sdata."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allocate variables to the read-only data section first if possible, then next in the small data section if possible, otherwise in data. This gives slightly slower code than the default, but reduces the amount of RAM required when executing, and thus may be preferred for some embedded systems."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Put uninitialized \"const\" variables in the read-only data section. This option is only meaningful in conjunction with -membedded-data."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify whether GCC may generate code that reads from executable sections. There are three possible settings: -mcode-readable=yes Instructions may freely access executable sections. This is the default setting. -mcode-readable=pcrel MIPS16 PC-relative load instructions can access executable sections, but other instructions must not do so. This option is useful on 4KSc and 4KSd processors when the code TLBs have the Read Inhibit bit set. It is also useful on processors that can be configured to have a dual instruction/data SRAM interface and that, like the M4K, automatically redirect PC-relative loads to the instruction RAM. -mcode-readable=no Instructions must not access executable sections. This option can be useful on targets that are configured to have a dual instruction/data SRAM interface but that (unlike the M4K) do not automatically redirect PC-relative loads to the instruction RAM."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable (disable) use of the %hi() and %lo() assembler relocation operators. This option has been superseded by -mexplicit-relocs but is retained for backwards compatibility."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) assembler relocation operators when dealing with symbolic addresses. The alternative, selected by -mno-explicit-relocs, is to use assembler macros instead. -mexplicit-relocs is the default if GCC was configured to use an assembler that supports relocation operators."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Trap (do not trap) on integer division by zero. The default is -mcheck-zero-division."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "MIPS systems check for division by zero by generating either a conditional trap or a break instruction. Using traps results in smaller code, but is only supported on MIPS II and later. Also, some versions of the Linux kernel have a bug that prevents trap from generating the proper signal (\"SIGFPE\"). Use -mdivide-traps to allow conditional traps on architectures that support them and -mdivide-breaks to force the use of breaks. The default is usually -mdivide-traps, but this can be overridden at configure time using --with-divide=breaks. Divide-by-zero checks can be completely disabled using -mno-check-zero-division."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable (disable) an optimization that pairs consecutive load or store instructions to enable load/store bonding. This option is enabled by default but only takes effect when the selected architecture is known to support bonding."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable (disable) direct unaligned access for MIPS Release 6. MIPSr6 requires load/store unaligned-access support, by hardware or trap&emulate. So -mno-unaligned-access may be needed by kernel."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force (do not force) the use of \"memcpy\" for non-trivial block moves. The default is -mno-memcpy, which allows GCC to inline most constant-sized copies."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable (do not disable) use of the \"jal\" instruction. Calling functions using \"jal\" is more efficient but requires the caller and callee to be in the same 256 megabyte segment. This option has no effect on abicalls code. The default is -mno-long-calls."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable (disable) use of the \"mad\", \"madu\" and \"mul\" instructions, as provided by the R4650 ISA."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable (disable) use of the \"madd\" and \"msub\" integer instructions. The default is -mimadd on architectures that support \"madd\" and \"msub\" except for the 74k architecture where it was found to generate slower code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable (disable) use of the floating-point multiply-accumulate instructions, when they are available. The default is -mfused-madd. On the R8000 CPU when multiply-accumulate instructions are used, the intermediate product is calculated to infinite precision and is not subject to the FCSR Flush to Zero bit. This may be undesirable in some circumstances. On other processors the result is numerically identical to the equivalent computation using separate multiply, add, subtract and negate instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Tell the MIPS assembler to not run its preprocessor over user assembler files (with a .s suffix) when assembling them."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Work around the 24K E48 (lost data on stores during refill) errata. The workarounds are implemented by the assembler rather than by GCC."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Work around certain R4000 CPU errata: - A double-word or a variable shift may give an incorrect result if executed immediately after starting an integer division. - A double-word or a variable shift may give an incorrect result if executed while an integer multiplication is in progress. - An integer division may give an incorrect result if started in a delay slot of a taken branch or a jump."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Work around certain R4400 CPU errata: - A double-word or a variable shift may give an incorrect result if executed immediately after starting an integer division."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Work around certain R10000 errata: - \"ll\"/\"sc\" sequences may not behave atomically on revisions prior to 3.0. They may deadlock on revisions 2.6 and earlier. This option can only be used if the target architecture supports branch-likely instructions. -mfix-r10000 is the default when -march=r10000 is used; -mno-fix-r10000 is the default otherwise."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not attempt to schedule the preceding instruction into the delay slot of a branch instruction placed at the end of a short loop of six instructions or fewer and always schedule a \"nop\" instruction there instead. The short loop bug under certain conditions causes loops to execute only once or twice, due to a hardware bug in the R5900 chip. The workaround is implemented by the assembler rather than by GCC."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Work around the RM7000 \"dmult\"/\"dmultu\" errata. The workarounds are implemented by the assembler rather than by GCC."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Work around certain VR4120 errata: - \"dmultu\" does not always produce the correct result. - \"div\" and \"ddiv\" do not always produce the correct result if one of the operands is negative. The workarounds for the division errata rely on special functions in libgcc.a. At present, these functions are only provided by the \"mips64vr*-elf\" configurations. Other VR4120 errata require a NOP to be inserted between certain pairs of instructions. These errata are handled by the assembler, not by GCC itself."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Work around the VR4130 \"mflo\"/\"mfhi\" errata. The workarounds are implemented by the assembler rather than by GCC, although GCC avoids using \"mflo\" and \"mfhi\" if the VR4130 \"macc\", \"macchi\", \"dmacc\" and \"dmacchi\" instructions are available instead."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Work around certain SB-1 CPU core errata. (This flag currently works around the SB-1 revision 2 \"F1\" and \"F2\" floating-point errata.)"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify whether GCC should insert cache barriers to avoid the side effects of speculation on R10K processors. In common with many processors, the R10K tries to predict the outcome of a conditional branch and speculatively executes instructions from the \"taken\" branch. It later aborts these instructions if the predicted outcome is wrong. However, on the R10K, even aborted instructions can have side effects. This problem only affects kernel stores and, depending on the system, kernel loads. As an example, a speculatively-executed store may load the target memory into cache and mark the cache line as dirty, even if the store itself is later aborted. If a DMA operation writes to the same area of memory before the \"dirty\" line is flushed, the cached data overwrites the DMA-ed data. See the R10K processor manual for a full description, including other potential problems. One workaround is to insert cache barrier instructions before every memory access that might be speculatively executed and that might have side effects even if aborted. -mr10k-cache-barrier=setting controls GCC's implementation of this workaround. It assumes that aborted accesses to any byte in the following regions does not have side effects: 1. the memory occupied by the current function's stack frame; 2. the memory occupied by an incoming stack argument; 3. the memory occupied by an object with a link-time-constant address. It is the kernel's responsibility to ensure that speculative accesses to these regions are indeed safe. If the input program contains a function declaration such as: void foo (void); then the implementation of \"foo\" must allow \"j foo\" and \"jal foo\" to be executed speculatively. GCC honors this restriction for functions it compiles itself. It expects non-GCC functions (such as hand-written assembly code) to do the same. The option has three forms: -mr10k-cache-barrier=load-store Insert a cache barrier before a load or store that might be speculatively executed and that might have side effects even if aborted. -mr10k-cache-barrier=store Insert a cache barrier before a store that might be speculatively executed and that might have side effects even if aborted. -mr10k-cache-barrier=none Disable the insertion of cache barriers. This is the default setting."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies the function to call to flush the I and D caches, or to not call any such function. If called, the function must take the same arguments as the common \"flushfunc\", that is, the address of the memory range for which the cache is being flushed, the size of the memory range, and the number 3 (to flush both caches). The default depends on the target GCC was configured for, but commonly is either \"flushfunc\" or \"cpuflush\". mbranch-cost=num Set the cost of branches to roughly num \"simple\" instructions. This cost is only a heuristic and is not guaranteed to produce consistent results across releases. A zero cost redundantly selects the default, which is based on the -mtune setting."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable or disable use of Branch Likely instructions, regardless of the default for the selected architecture. By default, Branch Likely instructions may be generated if they are supported by the selected architecture. An exception is for the MIPS32 and MIPS64 architectures and processors that implement those architectures; for those, Branch Likely instructions are not be generated by default because the MIPS32 and MIPS64 architectures specifically deprecate their use."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These options control which form of branches will be generated. The default is -mcompact-branches=optimal. The -mcompact-branches=never option ensures that compact branch instructions will never be generated. The -mcompact-branches=always option ensures that a compact branch instruction will be generated if available for MIPS Release 6 onwards. If a compact branch instruction is not available (or pre-R6), a delay slot form of the branch will be used instead. If it is used for MIPS16/microMIPS targets, it will be just ignored now. The behaviour for MIPS16/microMIPS may change in future, since they do have some compact branch instructions. The -mcompact-branches=optimal option will cause a delay slot branch to be used if one is available in the current ISA and the delay slot is successfully filled. If the delay slot is not filled, a compact branch will be chosen if one is available."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies whether FP exceptions are enabled. This affects how FP instructions are scheduled for some processors. The default is that FP exceptions are enabled. For instance, on the SB-1, if FP exceptions are disabled, and we are emitting 64-bit code, then we can use both FP pipes. Otherwise, we can only use one FP pipe."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The VR4130 pipeline is two-way superscalar, but can only issue two instructions together if the first one is 8-byte aligned. When this option is enabled, GCC aligns pairs of instructions that it thinks should execute in parallel. This option only has an effect when optimizing for the VR4130. It normally makes code faster, but at the expense of making it bigger. It is enabled by default at optimization level -O3."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable (disable) generation of \"synci\" instructions on architectures that support it. The \"synci\" instructions (if enabled) are generated when \"builtinclearcache\" is compiled. This option defaults to -mno-synci, but the default can be overridden by configuring GCC with --with-synci. When compiling code for single processor systems, it is generally safe to use \"synci\". However, on many multi-core (SMP) systems, it does not invalidate the instruction caches on all cores and may lead to undefined behavior."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Try to turn PIC calls that are normally dispatched via register $25 into direct calls. This is only possible if the linker can resolve the destination at link time and if the destination is within range for a direct call. -mrelax-pic-calls is the default if GCC was configured to use an assembler and a linker that support the \".reloc\" assembly directive and -mexplicit-relocs is in effect. With -mno-explicit-relocs, this optimization can be performed by the assembler and the linker alone without help from the compiler."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit (do not emit) code that allows \"mcount\" to modify the calling function's return address. When enabled, this option extends the usual \"mcount\" interface with a new ra- address parameter, which has type \"intptrt *\" and is passed in register $12. \"mcount\" can then modify the return address by doing both of the following: * Returning the new address in register $31. * Storing the new address in \"*ra-address\", if ra-address is nonnull. The default is -mno-mcount-ra-address."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable (disable) frame header optimization in the o32 ABI. When using the o32 ABI, calling functions will allocate 16 bytes on the stack for the called function to write out register arguments. When enabled, this optimization will suppress the allocation of the frame header if it can be determined that it is unused. This optimization is off by default at all optimization levels."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When applicable, enable (disable) the generation of \"lwxc1\", \"swxc1\", \"ldxc1\", \"sdxc1\" instructions. Enabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When applicable, enable (disable) the generation of 4-operand \"madd.s\", \"madd.d\" and related instructions. Enabled by default. MMIX Options These options are defined for the MMIX:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify that intrinsic library functions are being compiled, passing all values in registers, no matter the size."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate floating-point comparison instructions that compare with respect to the \"rE\" epsilon register."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that passes function parameters and return values that (in the called function) are seen as registers $0 and up, as opposed to the GNU ABI which uses global registers $231 and up."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When reading data from memory in sizes shorter than 64 bits, use (do not use) zero- extending load instructions by default, rather than sign-extending ones."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Make the result of a division yielding a remainder have the same sign as the divisor. With the default, -mno-knuthdiv, the sign of the remainder follows the sign of the dividend. Both methods are arithmetically valid, the latter being almost exclusively used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Prepend (do not prepend) a : to all global symbols, so the assembly code can be used with the \"PREFIX\" assembly directive."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate an executable in the ELF format, rather than the default mmo format used by the mmix simulator."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) the probable-branch instructions, when static branch prediction indicates a probable branch."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) code that uses base addresses. Using a base address automatically generates a request (handled by the assembler and the linker) for a constant to be set up in a global register. The register is used for one or more base address requests within the range 0 to 255 from the value held in the register. The generally leads to short and fast code, but the number of different data items that can be addressed is limited. This means that a program that uses lots of static data may require -mno-base-addresses."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force (do not force) generated code to have a single exit point in each function. MN10300 Options These -m options are defined for Matsushita MN10300 architectures:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code to avoid bugs in the multiply instructions for the MN10300 processors. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not generate code to avoid bugs in the multiply instructions for the MN10300 processors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code using features specific to the AM33 processor."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not generate code using features specific to the AM33 processor. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code using features specific to the AM33/2.0 processor."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code using features specific to the AM34 processor."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use the timing characteristics of the indicated CPU type when scheduling instructions. This does not change the targeted processor type. The CPU type must be one of mn10300, am33, am33-2 or am34."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When generating a function that returns a pointer, return the pointer in both \"a0\" and \"d0\". Otherwise, the pointer is returned only in \"a0\", and attempts to call such functions without a prototype result in errors. Note that this option is on by default; use -mno-return-pointer-on-d0 to disable it."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not link in the C run-time initialization object file."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Indicate to the linker that it should perform a relaxation optimization pass to shorten branches, calls and absolute memory addresses. This option only has an effect when used on the command line for the final link step. This option makes symbolic debugging impossible."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow the compiler to generate Long Instruction Word instructions if the target is the AM33 or later. This is the default. This option defines the preprocessor macro \"LIW\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not allow the compiler to generate Long Instruction Word instructions. This option defines the preprocessor macro \"NOLIW\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow the compiler to generate the SETLB and Lcc instructions if the target is the AM33 or later. This is the default. This option defines the preprocessor macro \"SETLB\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not allow the compiler to generate SETLB or Lcc instructions. This option defines the preprocessor macro \"NOSETLB\". Moxie Options"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate big-endian code. This is the default for moxie-*-* configurations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate little-endian code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate mul.x and umul.x instructions. This is the default for moxiebox-*-* configurations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not link in the C run-time initialization object file. MSP430 Options These options are defined for the MSP430:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force assembly output to always use hex constants. Normally such constants are signed decimals, but this option is available for testsuite and/or aesthetic purposes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select the MCU to target. This is used to create a C preprocessor symbol based upon the MCU name, converted to upper case and pre- and post-fixed with . This in turn is used by the msp430.h header file to select an MCU-specific supplementary header file. The option also sets the ISA to use. If the MCU name is one that is known to only support the 430 ISA then that is selected, otherwise the 430X ISA is selected. A generic MCU name of msp430 can also be used to select the 430 ISA. Similarly the generic msp430x MCU name selects the 430X ISA. In addition an MCU-specific linker script is added to the linker command line. The script's name is the name of the MCU with .ld appended. Thus specifying -mmcu=xxx on the gcc command line defines the C preprocessor symbol \"XXX\" and cause the linker to search for a script called xxx.ld. The ISA and hardware multiply supported for the different MCUs is hard-coded into GCC. However, an external devices.csv file can be used to extend device support beyond those that have been hard-coded. GCC searches for the devices.csv file using the following methods in the given precedence order, where the first method takes precendence over the second which takes precedence over the third. Include path specified with \"-I\" and \"-L\" devices.csv will be searched for in each of the directories specified by include paths and linker library search paths. Path specified by the environment variable MSP430GCCINCLUDEDIR Define the value of the global environment variable MSP430GCCINCLUDEDIR to the full path to the directory containing devices.csv, and GCC will search this directory for devices.csv. If devices.csv is found, this directory will also be registered as an include path, and linker library path. Header files and linker scripts in this directory can therefore be used without manually specifying \"-I\" and \"-L\" on the command line. The msp430-elf{,bare}/include/devices directory Finally, GCC will examine msp430-elf{,bare}/include/devices from the toolchain root directory. This directory does not exist in a default installation, but if the user has created it and copied devices.csv there, then the MCU data will be read. As above, this directory will also be registered as an include path, and linker library path. If none of the above search methods find devices.csv, then the hard-coded MCU data is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option enables or disables warnings about conflicts between the MCU name specified by the -mmcu option and the ISA set by the -mcpu option and/or the hardware multiply support set by the -mhwmult option. It also toggles warnings about unrecognized MCU names. This option is on by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies the ISA to use. Accepted values are msp430, msp430x and msp430xv2. This option is deprecated. The -mmcu= option should be used to select the ISA."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Link to the simulator runtime libraries and linker script. Overrides any scripts that would be selected by the -mmcu= option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use large-model addressing (20-bit pointers, 20-bit \"sizet\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use small-model addressing (16-bit pointers, 16-bit \"sizet\")."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is passed to the assembler and linker, and allows the linker to perform certain optimizations that cannot be done until the final link."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the use of a minimum runtime environment - no static initializers or constructors. This is intended for memory-constrained devices. The compiler includes special symbols in some objects that tell the linker and runtime which code fragments are required."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable reduced code size \"printf\" and \"puts\" library functions. The tiny implementations of these functions are not reentrant, so must be used with caution in multi-threaded applications. Support for streams has been removed and the string to be printed will always be sent to stdout via the \"write\" syscall. The string is not buffered before it is sent to write. This option requires Newlib Nano IO, so GCC must be configured with --enable-newlib-nano-formatted-io."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option takes an integer between 0 and 64 inclusive, and sets the maximum number of inline shift instructions which should be emitted to perform a shift operation by a constant amount. When this value needs to be exceeded, an mspabi helper function is used instead. The default value is 4. This only affects cases where a shift by multiple positions cannot be completed with a single instruction (e.g. all shifts >1 on the 430 ISA). Shifts of a 32-bit value are at least twice as costly, so the value passed for this option is divided by 2 and the resulting value used instead."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These options tell the compiler where to place functions and data that do not have one of the \"lower\", \"upper\", \"either\" or \"section\" attributes. Possible values are \"lower\", \"upper\", \"either\" or \"any\". The first three behave like the corresponding attribute. The fourth possible value - \"any\" - is the default. It leaves placement entirely up to the linker script and how it assigns the standard sections (\".text\", \".data\", etc) to the memory regions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option passes on a request to assembler to enable the fixes for the named silicon errata."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option passes on a request to the assembler to enable warning messages when a silicon errata might need to be applied."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Warn if devices.csv is not found or there are problem parsing it (default: on). NDS32 Options These options are defined for NDS32 implementations:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code in big-endian mode."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code in little-endian mode."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use reduced-set registers for register allocation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use full-set registers for register allocation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate conditional move instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not generate conditional move instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate performance extension instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not generate performance extension instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate performance extension 2 instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not generate performance extension 2 instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate string extension instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not generate string extension instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate v3 push25/pop25 instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not generate v3 push25/pop25 instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate 16-bit instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not generate 16-bit instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the size of each interrupt vector, which must be 4 or 16."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the size of each cache block, which must be a power of 2 between 4 and 512."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the name of the target architecture."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the code model to one of small All the data and read-only data segments must be within 512KB addressing space. The text segment must be within 16MB addressing space. medium The data segment must be within 512KB while the read-only data segment can be within 4GB addressing space. The text segment should be still within 16MB addressing space. large All the text and data segments can be within 4GB addressing space."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable constructor/destructor feature."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Guide linker to relax instructions. Nios II Options These are the options defined for the Altera Nios II processor."
        },
        {
            "flag": "-G",
            "long": null,
            "arg": null,
            "description": "Put global and static objects less than or equal to num bytes into the small data or BSS sections instead of the normal data or BSS sections. The default value of num is 8."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) GP-relative accesses. The following option names are recognized: none Do not generate GP-relative accesses. local Generate GP-relative accesses for small data objects that are not external, weak, or uninitialized common symbols. Also use GP-relative addressing for objects that have been explicitly placed in a small data section via a \"section\" attribute. global As for local, but also generate GP-relative accesses for small data objects that are external, weak, or common. If you use this option, you must ensure that all parts of your program (including libraries) are compiled with the same -G setting. data Generate GP-relative accesses for all data objects in the program. If you use this option, the entire data and BSS segments of your program must fit in 64K of memory and you must use an appropriate linker script to allocate them within the addressable range of the global pointer. all Generate GP-relative addresses for function pointers as well as data pointers. If you use this option, the entire text, data, and BSS segments of your program must fit in 64K of memory and you must use an appropriate linker script to allocate them within the addressable range of the global pointer. -mgpopt is equivalent to -mgpopt=local, and -mno-gpopt is equivalent to -mgpopt=none. The default is -mgpopt except when -fpic or -fPIC is specified to generate position- independent code. Note that the Nios II ABI does not permit GP-relative accesses from shared libraries. You may need to specify -mno-gpopt explicitly when building programs that include large amounts of small data, including large GOT data sections. In this case, the 16-bit offset for GP-relative addressing may not be large enough to allow access to the entire small data section."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option specifies additional section names that can be accessed via GP-relative addressing. It is most useful in conjunction with \"section\" attributes on variable declarations and a custom linker script. The regexp is a POSIX Extended Regular Expression. This option does not affect the behavior of the -G option, and the specified sections are in addition to the standard \".sdata\" and \".sbss\" small-data sections that are recognized by -mgpopt."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option specifies names of sections that can be accessed via a 16-bit offset from \"r0\"; that is, in the low 32K or high 32K of the 32-bit address space. It is most useful in conjunction with \"section\" attributes on variable declarations and a custom linker script. The regexp is a POSIX Extended Regular Expression. In contrast to the use of GP-relative addressing for small data, zero-based addressing is never generated by default and there are no conventional section names used in standard linker scripts for sections in the low or high areas of memory."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate little-endian (default) or big-endian (experimental) code, respectively."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This specifies the name of the target Nios II architecture. GCC uses this name to determine what kind of instructions it can emit when generating assembly code. Permissible names are: r1, r2. The preprocessor macro \"nios2arch\" is available to programs, with value 1 or 2, indicating the targeted ISA level."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force all load and store instructions to always bypass cache by using I/O variants of the instructions. The default is not to bypass the cache."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Volatile memory access bypass the cache using the I/O variants of the load and store instructions. The default is not to bypass the cache."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use table-based fast divide for small numbers. The default is to use the fast divide at -O3 and above."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable or disable emitting \"mul\", \"mulx\" and \"div\" family of instructions by the compiler. The default is to emit \"mul\" and not emit \"div\" and \"mulx\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable or disable generation of Nios II R2 BMX (bit manipulation) and CDX (code density) instructions. Enabling these instructions also requires -march=r2. Since these instructions are optional extensions to the R2 architecture, the default is not to emit them."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Each -mcustom-insn=N option enables use of a custom instruction with encoding N when generating code that uses insn. For example, -mcustom-fadds=253 generates custom instruction 253 for single-precision floating-point add operations instead of the default behavior of using a library call. The following values of insn are supported. Except as otherwise noted, floating-point operations are expected to be implemented with normal IEEE 754 semantics and correspond directly to the C operators or the equivalent GCC built-in functions. Single-precision floating point: fadds, fsubs, fdivs, fmuls Binary arithmetic operations. fnegs Unary negation. fabss Unary absolute value. fcmpeqs, fcmpges, fcmpgts, fcmples, fcmplts, fcmpnes Comparison operations. fmins, fmaxs Floating-point minimum and maximum. These instructions are only generated if -ffinite-math-only is specified. fsqrts Unary square root operation. fcoss, fsins, ftans, fatans, fexps, flogs Floating-point trigonometric and exponential functions. These instructions are only generated if -funsafe-math-optimizations is also specified. Double-precision floating point: faddd, fsubd, fdivd, fmuld Binary arithmetic operations. fnegd Unary negation. fabsd Unary absolute value. fcmpeqd, fcmpged, fcmpgtd, fcmpled, fcmpltd, fcmpned Comparison operations. fmind, fmaxd Double-precision minimum and maximum. These instructions are only generated if -ffinite-math-only is specified. fsqrtd Unary square root operation. fcosd, fsind, ftand, fatand, fexpd, flogd Double-precision trigonometric and exponential functions. These instructions are only generated if -funsafe-math-optimizations is also specified. Conversions: fextsd Conversion from single precision to double precision. ftruncds Conversion from double precision to single precision. fixsi, fixsu, fixdi, fixdu Conversion from floating point to signed or unsigned integer types, with truncation towards zero. round Conversion from single-precision floating point to signed integer, rounding to the nearest integer and ties away from zero. This corresponds to the \"builtinlroundf\" function when -fno-math-errno is used. floatis, floatus, floatid, floatud Conversion from signed or unsigned integer types to floating-point types. In addition, all of the following transfer instructions for internal registers X and Y must be provided to use any of the double-precision floating-point instructions. Custom instructions taking two double-precision source operands expect the first operand in the 64-bit register X. The other operand (or only operand of a unary operation) is given to the custom arithmetic instruction with the least significant half in source register src1 and the most significant half in src2. A custom instruction that returns a double- precision result returns the most significant 32 bits in the destination register and the other half in 32-bit register Y. GCC automatically generates the necessary code sequences to write register X and/or read register Y when double-precision floating-point instructions are used. fwrx Write src1 into the least significant half of X and src2 into the most significant half of X. fwry Write src1 into Y. frdxhi, frdxlo Read the most or least (respectively) significant half of X and store it in dest. frdy Read the value of Y and store it into dest. Note that you can gain more local control over generation of Nios II custom instructions by using the target(\"custom-insn=N\") and target(\"no-custom-insn\") function attributes or pragmas."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option enables a predefined, named set of custom instruction encodings (see -mcustom-insn above). Currently, the following sets are defined: -mcustom-fpu-cfg=60-1 is equivalent to: -mcustom-fmuls=252 -mcustom-fadds=253 -mcustom-fsubs=254 -fsingle-precision-constant -mcustom-fpu-cfg=60-2 is equivalent to: -mcustom-fmuls=252 -mcustom-fadds=253 -mcustom-fsubs=254 -mcustom-fdivs=255 -fsingle-precision-constant -mcustom-fpu-cfg=72-3 is equivalent to: -mcustom-floatus=243 -mcustom-fixsi=244 -mcustom-floatis=245 -mcustom-fcmpgts=246 -mcustom-fcmples=249 -mcustom-fcmpeqs=250 -mcustom-fcmpnes=251 -mcustom-fmuls=252 -mcustom-fadds=253 -mcustom-fsubs=254 -mcustom-fdivs=255 -fsingle-precision-constant -mcustom-fpu-cfg=fph2 is equivalent to: -mcustom-fabss=224 -mcustom-fnegs=225 -mcustom-fcmpnes=226 -mcustom-fcmpeqs=227 -mcustom-fcmpges=228 -mcustom-fcmpgts=229 -mcustom-fcmples=230 -mcustom-fcmplts=231 -mcustom-fmaxs=232 -mcustom-fmins=233 -mcustom-round=248 -mcustom-fixsi=249 -mcustom-floatis=250 -mcustom-fsqrts=251 -mcustom-fmuls=252 -mcustom-fadds=253 -mcustom-fsubs=254 -mcustom-fdivs=255 Custom instruction assignments given by individual -mcustom-insn= options override those given by -mcustom-fpu-cfg=, regardless of the order of the options on the command line. Note that you can gain more local control over selection of a FPU configuration by using the target(\"custom-fpu-cfg=name\") function attribute or pragma. The name fph2 is an abbreviation for Nios II Floating Point Hardware 2 Component. Please note that the custom instructions enabled by -mcustom-fmins=233 and -mcustom-fmaxs=234 are only generated if -ffinite-math-only is specified. The custom instruction enabled by -mcustom-round=248 is only generated if -fno-math-errno is specified. In contrast to the other configurations, -fsingle-precision-constant is not set. These additional -m options are available for the Altera Nios II ELF (bare-metal) target:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Link with HAL BSP. This suppresses linking with the GCC-provided C runtime startup and termination code, and is typically used in conjunction with -msys-crt0= to specify the location of the alternate startup code provided by the HAL BSP."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Link with a limited version of the C library, -lsmallc, rather than Newlib."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "startfile is the file name of the startfile (crt0) to use when linking. This option is only useful in conjunction with -mhal."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "systemlib is the library name of the library that provides low-level system calls required by the C library, e.g. \"read\" and \"write\". This option is typically used to link with a library provided by a HAL BSP. Nvidia PTX Options These options are defined for Nvidia PTX:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Ignored, but preserved for backward compatibility. Only 64-bit ABI is supported."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the specified PTX ISA target architecture (e.g. sm35). Valid architecture strings are sm30, sm35, sm53, sm70, sm75 and sm80. The default depends on how the compiler has been configured, see --with-arch. This option sets the value of the preprocessor macro \"PTXSM\"; for instance, for sm35, it has the value 350."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Alias of -march=."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select the closest available -march= value that is not more capable. For instance, for -march-map=sm50 select -march=sm35, and for -march-map=sm53 select -march=sm53."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the specified PTX ISA version (e.g. 7.0). Valid version strings include 3.1, 6.0, 6.3, and 7.0. The default PTX ISA version is 6.0, unless a higher version is required for specified PTX ISA target architecture via option -march=. This option sets the values of the preprocessor macros \"PTXISAVERSIONMAJOR\" and \"PTXISAVERSIONMINOR\"; for instance, for 3.1 the macros have the values 3 and 1, respectively."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Link in code for a main kernel. This is for stand-alone instead of offloading execution."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Apply partitioned execution optimizations. This is the default when any level of optimization is selected."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that does not use \".local\" memory directly for stack storage. Instead, a per-warp stack pointer is maintained explicitly. This enables variable-length stack allocation (with variable-length arrays or \"alloca\"), and when global memory is used for underlying storage, makes it possible to access automatic variables from other threads, or with atomic instructions. This code generation variant is used for OpenMP offloading, but the option is exposed on its own for the purpose of testing the compiler; to generate code suitable for linking into programs using OpenMP offloading, use option -mgomp."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Switch to code generation variant that allows to execute all threads in each warp, while maintaining memory state and side effects as if only one thread in each warp was active outside of OpenMP SIMD regions. All atomic operations and calls to runtime (malloc, free, vprintf) are conditionally executed (iff current lane index equals the master lane index), and the register being assigned is copied via a shuffle instruction from the master lane. Outside of SIMD regions lane 0 is the master; inside, each thread sees itself as the master. Shared memory array \"int nvptxuni[]\" stores all-zeros or all- ones bitmasks for each warp, indicating current mode (0 outside of SIMD regions). Each thread can bitwise-and the bitmask at position \"tid.y\" with current lane index to compute the master lane index."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for use in OpenMP offloading: enables -msoft-stack and -muniform-simt options, and selects corresponding multilib variant. OpenRISC Options These options are defined for OpenRISC:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Configure a board specific runtime. This will be passed to the linker for newlib board library linking. The default is \"or1ksim\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is ignored; it is for compatibility purposes only. This used to select linker and preprocessor options for use with newlib."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select software or hardware divide (\"l.div\", \"l.divu\") instructions. This default is hardware divide."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select software or hardware multiply (\"l.mul\", \"l.muli\") instructions. This default is hardware multiply."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select software or hardware for floating point operations. The default is software."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When -mhard-float is selected, enables generation of double-precision floating point instructions. By default functions from libgcc are used to perform double-precision floating point operations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When -mhard-float is selected, enables generation of unordered floating point compare and set flag (\"lf.sfun*\") instructions. By default functions from libgcc are used to perform unordered floating point compare and set flag operations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable generation of conditional move (\"l.cmov\") instructions. By default the equivalent will be generated using set and branch."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable generation of rotate right (\"l.ror\") instructions. By default functions from libgcc are used to perform rotate right operations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable generation of rotate right with immediate (\"l.rori\") instructions. By default functions from libgcc are used to perform rotate right with immediate operations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable generation of sign extension (\"l.ext*\") instructions. By default memory loads are used to perform sign extension."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable generation of compare and set flag with immediate (\"l.sf*i\") instructions. By default extra instructions will be generated to store the immediate to a register first."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable generation of shift with immediate (\"l.srai\", \"l.srli\", \"l.slli\") instructions. By default extra instructions will be generated to store the immediate to a register first."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate OpenRISC code for the small model: The GOT is limited to 64k. This is the default model."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate OpenRISC code for the large model: The GOT may grow up to 4G in size. PDP-11 Options These options are defined for the PDP-11:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use hardware FPP floating point. This is the default. (FIS floating point on the PDP-11/40 is not supported.) Implies -m45."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use hardware floating point."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Return floating-point results in ac0 (fr0 in Unix assembler syntax)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Return floating-point results in memory. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a PDP-11/40. Implies -msoft-float -mno-split."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a PDP-11/45. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a PDP-11/10. Implies -msoft-float -mno-split."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use 16-bit \"int\". This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use 32-bit \"int\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Target has split instruction and data space. Implies -m45."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use Unix assembler syntax."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use DEC assembler syntax."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use GNU assembler syntax. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use the new LRA register allocator. By default, the old \"reload\" allocator is used. PowerPC Options These are listed under PRU Options These command-line options are defined for PRU target:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Link with a minimum runtime environment, with no support for static initializers and constructors. Using this option can significantly reduce the size of the final ELF binary. Beware that the compiler could still generate code with static initializers and constructors. It is up to the programmer to ensure that the source program will not use those features."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the PRU MCU variant to use. Check Newlib for the exact list of supported MCUs."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Make GCC pass the --no-relax command-line option to the linker instead of the --relax option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow (or do not allow) GCC to use the LOOP instruction."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the ABI variant to output code for. -mabi=ti selects the unmodified TI ABI while -mabi=gnu selects a GNU variant that copes more naturally with certain GCC assumptions. These are the differences: Function Pointer Size TI ABI specifies that function (code) pointers are 16-bit, whereas GNU supports only 32-bit data and code pointers. Optional Return Value Pointer Function return values larger than 64 bits are passed by using a hidden pointer as the first argument of the function. TI ABI, though, mandates that the pointer can be NULL in case the caller is not using the returned value. GNU always passes and expects a valid return value pointer. The current -mabi=ti implementation simply raises a compile error when any of the above code constructs is detected. As a consequence the standard C library cannot be built and it is omitted when linking with -mabi=ti. Relaxation is a GNU feature and for safety reasons is disabled when using -mabi=ti. The TI toolchain does not emit relocations for QBBx instructions, so the GNU linker cannot adjust them when shortening adjacent LDI32 pseudo instructions. RISC-V Options These command-line options are defined for RISC-V targets:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the cost of branches to roughly n instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When generating PIC code, do or don't allow the use of PLTs. Ignored for non-PIC. The default is -mplt."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify integer and floating-point calling convention. ABI-string contains two parts: the size of integer types and the registers used for floating-point types. For example -march=rv64ifd -mabi=lp64d means that long and pointers are 64-bit (implicitly defining int to be 32-bit), and that floating-point values up to 64 bits wide are passed in F registers. Contrast this with -march=rv64ifd -mabi=lp64f, which still allows the compiler to generate code that uses the F and D extensions but only allows floating-point values up to 32 bits long to be passed in registers; or -march=rv64ifd -mabi=lp64, in which no floating-point arguments will be passed in registers. The default for this argument is system dependent, users who want a specific calling convention should specify one explicitly. The valid calling conventions are: ilp32, ilp32f, ilp32d, lp64, lp64f, and lp64d. Some calling conventions are impossible to implement on some ISAs: for example, -march=rv32if -mabi=ilp32d is invalid because the ABI requires 64-bit values be passed in F registers, but F registers are only 32 bits wide. There is also the ilp32e ABI that can only be used with the rv32e architecture. This ABI is not well specified at present, and is subject to change."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do or don't use hardware floating-point divide and square root instructions. This requires the F or D extensions for floating-point registers. The default is to use them if the specified architecture has these instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do or don't use hardware instructions for integer division. This requires the M extension. The default is to use them if the specified architecture has these instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the version of the RISC-V Unprivileged (formerly User-Level) ISA specification to produce code conforming to. The possibilities for ISA-spec-string are: 2.2 Produce code conforming to version 2.2. 20190608 Produce code conforming to version 20190608. 20191213 Produce code conforming to version 20191213. The default is -misa-spec=20191213 unless GCC has been configured with --with-isa-spec= specifying a different default version."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for given RISC-V ISA (e.g. rv64im). ISA strings must be lower-case. Examples include rv64i, rv32g, rv32e, and rv32imaf. When -march= is not specified, use the setting from -mcpu. If both -march and -mcpu= are not specified, the default for this argument is system dependent, users who want a specific architecture extensions should specify one explicitly."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use architecture of and optimize the output for the given processor, specified by particular CPU name. Permissible values for this option are: sifive-e20, sifive-e21, sifive-e24, sifive-e31, sifive-e34, sifive-e76, sifive-s21, sifive-s51, sifive-s54, sifive-s76, sifive-u54, and sifive-u74."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Optimize the output for the given processor, specified by microarchitecture or particular CPU name. Permissible values for this option are: rocket, sifive-3-series, sifive-5-series, sifive-7-series, thead-c906, size, and all valid options for -mcpu=. When -mtune= is not specified, use the setting from -mcpu, the default is rocket if both are not specified. The size choice is not intended for use by end-users. This is used when -Os is specified. It overrides the instruction cost info provided by -mtune=, but does not override the pipeline info. This helps reduce code size while still giving good performance."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Attempt to keep the stack boundary aligned to a 2 raised to num byte boundary. If -mpreferred-stack-boundary is not specified, the default is 4 (16 bytes or 128-bits). Warning: If you use this switch, then you must build all modules with the same value, including any libraries. This includes the system libraries and startup modules."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Put global and static data smaller than n bytes into a special section (on some targets)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do or don't use smaller but slower prologue and epilogue code that uses library function calls. The default is to use fast inline prologues and epilogues."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do or don't use smaller but slower subword atomic emulation code that uses libatomic function calls. The default is to use fast inline subword atomics that do not require libatomic."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do or do not attempt to make more use of compressed load/store instructions by replacing a load/store of 'base register + large offset' with a new load/store of 'new base + small offset'. If the new base gets stored in a compressed register, then the new load/store can be compressed. Currently targets 32-bit integer load/stores only."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not or do generate unaligned memory accesses. The default is set depending on whether the processor we are optimizing for supports fast unaligned access or not."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the medium-low code model. The program and its statically defined symbols must lie within a single 2 GiB address range and must lie between absolute addresses -2 GiB and +2 GiB. Programs can be statically or dynamically linked. This is the default code model."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the medium-any code model. The program and its statically defined symbols must be within any single 2 GiB address range. Programs can be statically or dynamically linked. The code generated by the medium-any code model is position-independent, but is not guaranteed to function correctly when linked into position-independent executables or libraries."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use or do not use assembler relocation operators when dealing with symbolic addresses. The alternative is to use assembler macros instead, which may limit optimization."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Take advantage of linker relaxations to reduce the number of instructions required to materialize symbol addresses. The default is to take advantage of linker relaxations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit (do not emit) RISC-V attribute to record extra information into ELF objects. This feature requires at least binutils 2.32."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enables or disables the CSR checking."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Control how GCC aligns variables and constants of array, structure, or union types. Supported values for type are xlen which uses x register width as the alignment value, and natural which uses natural alignment. xlen is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate big-endian code. This is the default when GCC is configured for a riscv64be-*-* or riscv32be-*-* target."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate little-endian code. This is the default when GCC is configured for a riscv64-*-* or riscv32-*-* but not a riscv64be-*-* or riscv32be-*-* target."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate stack protection code using canary at guard. Supported locations are global for a global canary or tls for per-thread canary in the TLS block. With the latter choice the options -mstack-protector-guard-reg=reg and -mstack-protector-guard-offset=offset furthermore specify which register to use as base register for reading the canary, and from what offset from that base register. There is no default register or offset as this is entirely for use within the Linux kernel. RL78 Options"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Links in additional target libraries to support operation within a simulator."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies the type of hardware multiplication and division support to be used. The simplest is \"none\", which uses software for both multiplication and division. This is the default. The \"g13\" value is for the hardware multiply/divide peripheral found on the RL78/G13 (S2 core) targets. The \"g14\" value selects the use of the multiplication and division instructions supported by the RL78/G14 (S3 core) parts. The value \"rl78\" is an alias for \"g14\" and the value \"mg10\" is an alias for \"none\". In addition a C preprocessor macro is defined, based upon the setting of this option. Possible values are: \"RL78MULNONE\", \"RL78MULG13\" or \"RL78MULG14\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies the RL78 core to target. The default is the G14 core, also known as an S3 core or just RL78. The G13 or S2 core does not have multiply or divide instructions, instead it uses a hardware peripheral for these operations. The G10 or S1 core does not have register banks, so it uses a different calling convention. If this option is set it also selects the type of hardware multiply support to use, unless this is overridden by an explicit -mmul=none option on the command line. Thus specifying -mcpu=g13 enables the use of the G13 hardware multiply peripheral and specifying -mcpu=g10 disables the use of hardware multiplications altogether. Note, although the RL78/G14 core is the default target, specifying -mcpu=g14 or -mcpu=rl78 on the command line does change the behavior of the toolchain since it also enables G14 hardware multiply support. If these options are not specified on the command line then software multiplication routines will be used even though the code targets the RL78 core. This is for backwards compatibility with older toolchains which did not have hardware multiply and divide support. In addition a C preprocessor macro is defined, based upon the setting of this option. Possible values are: \"RL78G10\", \"RL78G13\" or \"RL78G14\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These are aliases for the corresponding -mcpu= option. They are provided for backwards compatibility."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow the compiler to use all of the available registers. By default registers \"r24..r31\" are reserved for use in interrupt handlers. With this option enabled these registers can be used in ordinary functions as well."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Make the \"double\" data type be 64 bits (-m64bit-doubles) or 32 bits (-m32bit-doubles) in size. The default is -m32bit-doubles."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies that interrupt handler functions should preserve the MDUC registers. This is only necessary if normal code might use the MDUC registers, for example because it performs multiplication and division operations. The default is to ignore the MDUC registers as this makes the interrupt handlers faster. The target option -mg13 needs to be passed for this to work as this feature is only available on the G13 target (S2 core). The MDUC registers will only be saved if the interrupt handler performs a multiplication or division operation or it calls another function. IBM RS/6000 and PowerPC Options These -m options are defined for the IBM RS/6000 and PowerPC:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "You use these options to specify which instructions are available on the processor you are using. The default value of these options is determined when configuring GCC. Specifying the -mcpu=cputype overrides the specification of these options. We recommend you use the -mcpu=cputype option rather than the options listed above. Specifying -mpowerpc-gpopt allows GCC to use the optional PowerPC architecture instructions in the General Purpose group, including floating-point square root. Specifying -mpowerpc-gfxopt allows GCC to use the optional PowerPC architecture instructions in the Graphics group, including floating-point select. The -mmfcrf option allows GCC to generate the move from condition register field instruction implemented on the POWER4 processor and other processors that support the PowerPC V2.01 architecture. The -mpopcntb option allows GCC to generate the popcount and double-precision FP reciprocal estimate instruction implemented on the POWER5 processor and other processors that support the PowerPC V2.02 architecture. The -mpopcntd option allows GCC to generate the popcount instruction implemented on the POWER7 processor and other processors that support the PowerPC V2.06 architecture. The -mfprnd option allows GCC to generate the FP round to integer instructions implemented on the POWER5+ processor and other processors that support the PowerPC V2.03 architecture. The -mcmpb option allows GCC to generate the compare bytes instruction implemented on the POWER6 processor and other processors that support the PowerPC V2.05 architecture. The -mhard-dfp option allows GCC to generate the decimal floating-point instructions implemented on some POWER processors. The -mpowerpc64 option allows GCC to generate the additional 64-bit instructions that are found in the full PowerPC64 architecture and to treat GPRs as 64-bit, doubleword quantities. GCC defaults to -mno-powerpc64."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set architecture type, register usage, and instruction scheduling parameters for machine type cputype. Supported values for cputype are 401, 403, 405, 405fp, 440, 440fp, 464, 464fp, 476, 476fp, 505, 601, 602, 603, 603e, 604, 604e, 620, 630, 740, 7400, 7450, 750, 801, 821, 823, 860, 970, 8540, a2, e300c2, e300c3, e500mc, e500mc64, e5500, e6500, ec603e, G3, G4, G5, titan, power3, power4, power5, power5+, power6, power6x, power7, power8, power9, power10, powerpc, powerpc64, powerpc64le, rs64, and native. -mcpu=powerpc, -mcpu=powerpc64, and -mcpu=powerpc64le specify pure 32-bit PowerPC (either endian), 64-bit big endian PowerPC and 64-bit little endian PowerPC architecture machine types, with an appropriate, generic processor model assumed for scheduling purposes. Specifying native as cpu type detects and selects the architecture option that corresponds to the host processor of the system performing the compilation. -mcpu=native has no effect if GCC does not recognize the processor. The other options specify a specific processor. Code generated under those options runs best on that processor, and may not run at all on others. The -mcpu options automatically enable or disable the following options: -maltivec -mfprnd -mhard-float -mmfcrf -mmultiple -mpopcntb -mpopcntd -mpowerpc64 -mpowerpc-gpopt -mpowerpc-gfxopt -mmulhw -mdlmzb -mmfpgpr -mvsx -mcrypto -mhtm -mpower8-fusion -mpower8-vector -mquad-memory -mquad-memory-atomic -mfloat128 -mfloat128-hardware -mprefixed -mpcrel -mmma -mrop-protect The particular options set for any particular CPU varies between compiler versions, depending on what setting seems to produce optimal code for that CPU; it doesn't necessarily reflect the actual hardware's capabilities. If you wish to set an individual option to a particular value, you may specify it after the -mcpu option, like -mcpu=970 -mno-altivec. On AIX, the -maltivec and -mpowerpc64 options are not enabled or disabled by the -mcpu option at present because AIX does not have full support for these options. You may still enable or disable them individually if you're sure it'll work in your environment."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the instruction scheduling parameters for machine type cputype, but do not set the architecture type or register usage, as -mcpu=cputype does. The same values for cputype are used for -mtune as for -mcpu. If both are specified, the code generated uses the architecture and registers set by -mcpu, but the scheduling parameters set by -mtune."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate PowerPC64 code for the small model: The TOC is limited to 64k."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate PowerPC64 code for the medium model: The TOC and other static data may be up to a total of 4G in size. This is the default for 64-bit Linux."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate PowerPC64 code for the large model: The TOC may be up to 4G in size. Other data and code is only limited by the 64-bit address space."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses (does not use) AltiVec instructions, and also enable the use of built-in functions that allow more direct access to the AltiVec instruction set. You may also need to set -mabi=altivec to adjust the current ABI with AltiVec ABI enhancements. When -maltivec is used, the element order for AltiVec intrinsics such as \"vecsplat\", \"vecextract\", and \"vecinsert\" match array element order corresponding to the endianness of the target. That is, element zero identifies the leftmost element in a vector register when targeting a big-endian platform, and identifies the rightmost element in a vector register when targeting a little-endian platform."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate VRSAVE instructions when generating AltiVec code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that allows ld and ld.so to build executables and shared libraries with non-executable \".plt\" and \".got\" sections. This is a PowerPC 32-bit SYSV ABI option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses a BSS \".plt\" section that ld.so fills in, and requires \".plt\" and \".got\" sections that are both writable and executable. This is a PowerPC 32-bit SYSV ABI option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This switch enables or disables the generation of ISEL instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses (does not use) vector/scalar (VSX) instructions, and also enable the use of built-in functions that allow more direct access to the VSX instruction set."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the use (disable) of the built-in functions that allow direct access to the cryptographic instructions that were added in version 2.07 of the PowerPC ISA."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable (disable) the use of the built-in functions that allow direct access to the Hardware Transactional Memory (HTM) instructions that were added in version 2.07 of the PowerPC ISA."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that keeps (does not keeps) some integer operations adjacent so that the instructions can be fused together on power8 and later processors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses (does not use) the vector and scalar instructions that were added in version 2.07 of the PowerPC ISA. Also enable the use of built-in functions that allow more direct access to the vector instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses (does not use) the non-atomic quad word memory instructions. The -mquad-memory option requires use of 64-bit mode."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses (does not use) the atomic quad word memory instructions. The -mquad-memory-atomic option requires use of 64-bit mode."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable/disable the float128 keyword for IEEE 128-bit floating point and use either software emulation for IEEE 128-bit floating point or hardware instructions. The VSX instruction set (-mvsx) must be enabled to use the IEEE 128-bit floating point support. The IEEE 128-bit floating point is only supported on Linux. The default for -mfloat128 is enabled on PowerPC Linux systems using the VSX instruction set, and disabled on other systems. If you use the ISA 3.0 instruction set (-mpower9-vector or -mcpu=power9) on a 64-bit system, the IEEE 128-bit floating point support will also enable the generation of ISA 3.0 IEEE 128-bit floating point instructions. Otherwise, if you do not specify to generate ISA 3.0 instructions or you are targeting a 32-bit big endian system, IEEE 128-bit floating point will be done with software emulation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable/disable using ISA 3.0 hardware instructions to support the float128 data type. The default for -mfloat128-hardware is enabled on PowerPC Linux systems using the ISA 3.0 instruction set, and disabled on other systems."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for 32-bit or 64-bit environments of Darwin and SVR4 targets (including GNU/Linux). The 32-bit environment sets int, long and pointer to 32 bits and generates code that runs on any PowerPC variant. The 64-bit environment sets int to 32 bits and long and pointer to 64 bits, and generates code for PowerPC64, as for -mpowerpc64."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Modify generation of the TOC (Table Of Contents), which is created for every executable file. The -mfull-toc option is selected by default. In that case, GCC allocates at least one TOC entry for each unique non-automatic variable reference in your program. GCC also places floating-point constants in the TOC. However, only 16,384 entries are available in the TOC. If you receive a linker error message that saying you have overflowed the available TOC space, you can reduce the amount of TOC space used with the -mno-fp-in-toc and -mno-sum-in-toc options. -mno-fp-in-toc prevents GCC from putting floating-point constants in the TOC and -mno-sum-in-toc forces GCC to generate code to calculate the sum of an address and a constant at run time instead of putting that sum into the TOC. You may specify one or both of these options. Each causes GCC to produce very slightly slower and larger code at the expense of conserving TOC space. If you still run out of space in the TOC even when you specify both of these options, specify -mminimal-toc instead. This option causes GCC to make only one TOC entry for every file. When you specify this option, GCC produces code that is slower and larger but which uses extremely little TOC space. You may wish to use this option only on files that contain less frequently-executed code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable 64-bit AIX ABI and calling convention: 64-bit pointers, 64-bit \"long\" type, and the infrastructure needed to support them. Specifying -maix64 implies -mpowerpc64, while -maix32 disables the 64-bit ABI and implies -mno-powerpc64. GCC defaults to -maix32."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Produce code that conforms more closely to IBM XL compiler semantics when using AIX- compatible ABI. Pass floating-point arguments to prototyped functions beyond the register save area (RSA) on the stack in addition to argument FPRs. Do not assume that most significant double in 128-bit long double value is properly rounded when comparing values and converting to double. Use XL symbol names for long double support routines. The AIX calling convention was extended but not initially documented to handle an obscure K&R C case of calling a function that takes the address of its arguments with fewer arguments than declared. IBM XL compilers access floating-point arguments that do not fit in the RSA from the stack when a subroutine is compiled without optimization. Because always storing floating-point arguments on the stack is inefficient and rarely needed, this option is not enabled by default and only is necessary when calling subroutines compiled by IBM XL compilers without optimization."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Support IBM RS/6000 SP Parallel Environment (PE). Link an application written to use message passing with special startup code to enable the application to run. The system must have PE installed in the standard location (/usr/lpp/ppe.poe/), or the specs file must be overridden with the -specs= option to specify the appropriate directory location. The Parallel Environment does not support threads, so the -mpe option and the -pthread option are incompatible."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On AIX, 32-bit Darwin, and 64-bit PowerPC GNU/Linux, the option -malign-natural overrides the ABI-defined alignment of larger types, such as floating-point doubles, on their natural size-based boundary. The option -malign-power instructs GCC to follow the ABI- specified alignment rules. GCC defaults to the standard alignment defined in the ABI. On 64-bit Darwin, natural alignment is the default, and -malign-power is not supported."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that does not use (uses) the floating-point register set. Software floating-point emulation is provided if you use the -msoft-float option, and pass the option to GCC when linking."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses (does not use) the load multiple word instructions and the store multiple word instructions. These instructions are generated by default on POWER systems, and not generated on PowerPC systems. Do not use -mmultiple on little-endian PowerPC systems, since those instructions do not work when the processor is in little- endian mode. The exceptions are PPC740 and PPC750 which permit these instructions in little-endian mode."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses (does not use) the load or store instructions that update the base register to the address of the calculated memory location. These instructions are generated by default. If you use -mno-update, there is a small window between the time that the stack pointer is updated and the address of the previous frame is stored, which means code that walks the stack frame across interrupts or signals may get corrupted data."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that tries to avoid (not avoid) the use of indexed load or store instructions. These instructions can incur a performance penalty on Power6 processors in certain situations, such as when stepping through large arrays that cross a 16M boundary. This option is enabled by default when targeting Power6 and disabled otherwise."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses (does not use) the floating-point multiply and accumulate instructions. These instructions are generated by default if hardware floating point is used. The machine-dependent -mfused-madd option is now mapped to the machine-independent -ffp-contract=fast option, and -mno-fused-madd is mapped to -ffp-contract=off."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses (does not use) the half-word multiply and multiply-accumulate instructions on the IBM 405, 440, 464 and 476 processors. These instructions are generated by default when targeting those processors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses (does not use) the string-search dlmzb instruction on the IBM 405, 440, 464 and 476 processors. This instruction is generated by default when targeting those processors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems do not (do) force structures and unions that contain bit-fields to be aligned to the base type of the bit-field. For example, by default a structure containing nothing but 8 \"unsigned\" bit-fields of length 1 is aligned to a 4-byte boundary and has a size of 4 bytes. By using -mno-bit-align, the structure is aligned to a 1-byte boundary and is 1 byte in size."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems do not (do) assume that unaligned memory references are handled by the system."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that allows (does not allow) a static executable to be relocated to a different address at run time. A simple embedded PowerPC system loader should relocate the entire contents of \".got2\" and 4-byte locations listed in the \".fixup\" section, a table of 32-bit addresses generated by this option. For this to work, all objects linked together must be compiled with -mrelocatable or -mrelocatable-lib. -mrelocatable code aligns the stack to an 8-byte boundary."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Like -mrelocatable, -mrelocatable-lib generates a \".fixup\" section to allow static executables to be relocated at run time, but -mrelocatable-lib does not use the smaller stack alignment of -mrelocatable. Objects compiled with -mrelocatable-lib may be linked with objects compiled with any combination of the -mrelocatable options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems do not (do) assume that register 2 contains a pointer to a global area pointing to the addresses used in the program."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems compile code for the processor in little- endian mode. The -mlittle-endian option is the same as -mlittle."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems compile code for the processor in big-endian mode. The -mbig-endian option is the same as -mbig."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On Darwin and Mac OS X systems, compile code so that it is not relocatable, but that its external references are relocatable. The resulting code is suitable for applications, but not shared libraries."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Treat the register used for PIC addressing as read-only, rather than loading it in the prologue for each function. The runtime system is responsible for initializing this register with an appropriate value before execution begins."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls the priority that is assigned to dispatch-slot restricted instructions during the second scheduling pass. The argument priority takes the value 0, 1, or 2 to assign no, highest, or second-highest (respectively) priority to dispatch-slot restricted instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls which dependences are considered costly by the target during instruction scheduling. The argument dependencetype takes one of the following values: no No dependence is costly. all All dependences are costly. truestoretoload A true dependence from store to load is costly. storetoload Any dependence from store to load is costly. number Any dependence for which the latency is greater than or equal to number is costly."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls which NOP insertion scheme is used during the second scheduling pass. The argument scheme takes one of the following values: no Don't insert NOPs. pad Pad with NOPs any dispatch group that has vacant issue slots, according to the scheduler's grouping. regroupexact Insert NOPs to force costly dependent insns into separate groups. Insert exactly as many NOPs as needed to force an insn to a new group, according to the estimated processor grouping. number Insert NOPs to force costly dependent insns into separate groups. Insert number NOPs to force an insn to a new group."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems compile code using calling conventions that adhere to the March 1995 draft of the System V Application Binary Interface, PowerPC processor supplement. This is the default unless you configured GCC using powerpc-*-eabiaix."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify both -mcall-sysv and -meabi options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify both -mcall-sysv and -mno-eabi options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems compile code for the AIX operating system."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems compile code for the Linux-based GNU system."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems compile code for the FreeBSD operating system."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems compile code for the NetBSD operating system."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems compile code for the OpenBSD operating system."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Select the type of traceback table. Valid values for tracebacktype are full, part, and no."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Return all structures in memory (as specified by the AIX ABI)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Return structures smaller than 8 bytes in registers (as specified by the SVR4 ABI)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Extend the current ABI with a particular extension, or remove such extension. Valid values are: altivec, no-altivec, ibmlongdouble, ieeelongdouble, elfv1, elfv2, and for AIX: vec-extabi, vec-default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Change the current ABI to use IBM extended-precision long double. This is not likely to work if your system defaults to using IEEE extended-precision long double. If you change the long double type from IEEE extended-precision, the compiler will issue a warning unless you use the -Wno-psabi option. Requires -mlong-double-128 to be enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Change the current ABI to use IEEE extended-precision long double. This is not likely to work if your system defaults to using IBM extended-precision long double. If you change the long double type from IBM extended-precision, the compiler will issue a warning unless you use the -Wno-psabi option. Requires -mlong-double-128 to be enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Change the current ABI to use the ELFv1 ABI. This is the default ABI for big-endian PowerPC 64-bit Linux. Overriding the default ABI requires special system support and is likely to fail in spectacular ways."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Change the current ABI to use the ELFv2 ABI. This is the default ABI for little-endian PowerPC 64-bit Linux. Overriding the default ABI requires special system support and is likely to fail in spectacular ways."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit .gnuattribute assembly directives to set tag/value pairs in a .gnu.attributes section that specify ABI variations in function parameters or return values."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems assume that all calls to variable argument functions are properly prototyped. Otherwise, the compiler must insert an instruction before every non-prototyped call to set or clear bit 6 of the condition code register (\"CR\") to indicate whether floating-point values are passed in the floating-point registers in case the function takes variable arguments. With -mprototype, only calls to prototyped variable argument functions set or clear the bit."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On embedded PowerPC systems, assume that the startup module is called sim-crt0.o and that the standard C libraries are libsim.a and libc.a. This is the default for powerpc-*-eabisim configurations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On embedded PowerPC systems, assume that the startup module is called crt0.o and the standard C libraries are libmvme.a and libc.a."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On embedded PowerPC systems, assume that the startup module is called crt0.o and the standard C libraries are libads.a and libc.a."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On embedded PowerPC systems, assume that the startup module is called crt0.o and the standard C libraries are libyk.a and libc.a."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems, specify that you are compiling for a VxWorks system."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On embedded PowerPC systems, set the \"PPCEMB\" bit in the ELF flags header to indicate that eabi extended relocations are used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems do (do not) adhere to the Embedded Applications Binary Interface (EABI), which is a set of modifications to the System V.4 specifications. Selecting -meabi means that the stack is aligned to an 8-byte boundary, a function \"eabi\" is called from \"main\" to set up the EABI environment, and the -msdata option can use both \"r2\" and \"r13\" to point to two separate small data areas. Selecting -mno-eabi means that the stack is aligned to a 16-byte boundary, no EABI initialization function is called from \"main\", and the -msdata option only uses \"r13\" to point to a single small data area. The -meabi option is on by default if you configured GCC using one of the powerpc*-*-eabi* options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems, put small initialized \"const\" global and static data in the \".sdata2\" section, which is pointed to by register \"r2\". Put small initialized non-\"const\" global and static data in the \".sdata\" section, which is pointed to by register \"r13\". Put small uninitialized global and static data in the \".sbss\" section, which is adjacent to the \".sdata\" section. The -msdata=eabi option is incompatible with the -mrelocatable option. The -msdata=eabi option also sets the -memb option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems, put small global and static data in the \".sdata\" section, which is pointed to by register \"r13\". Put small uninitialized global and static data in the \".sbss\" section, which is adjacent to the \".sdata\" section. The -msdata=sysv option is incompatible with the -mrelocatable option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems, if -meabi is used, compile code the same as -msdata=eabi, otherwise compile code the same as -msdata=sysv."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems, put small global data in the \".sdata\" section. Put small uninitialized global data in the \".sbss\" section. Do not use register \"r13\" to address small data however. This is the default behavior unless other -msdata options are used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On embedded PowerPC systems, put all initialized global and static data in the \".data\" section, and all uninitialized data in the \".bss\" section."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Put read-only objects in the \".sdata\" section as well. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Inline all block moves (such as calls to \"memcpy\" or structure copies) less than or equal to num bytes. The minimum value for num is 32 bytes on 32-bit targets and 64 bytes on 64-bit targets. The default value is target-specific."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate non-looping inline code for all block compares (such as calls to \"memcmp\" or structure compares) less than or equal to num bytes. If num is 0, all inline expansion (non-loop and loop) of block compare is disabled. The default value is target-specific."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate an inline expansion using loop code for all block compares that are less than or equal to num bytes, but greater than the limit for non-loop inline block compare expansion. If the block length is not constant, at most num bytes will be compared before \"memcmp\" is called to compare the remainder of the block. The default value is target- specific."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Compare at most num string bytes with inline code. If the difference or end of string is not found at the end of the inline compare a call to \"strcmp\" or \"strncmp\" will take care of the rest of the comparison. The default is 64 bytes."
        },
        {
            "flag": "-G",
            "long": null,
            "arg": null,
            "description": "On embedded PowerPC systems, put global and static items less than or equal to num bytes into the small data or BSS sections instead of the normal data or BSS section. By default, num is 8. The -G num switch is also passed to the linker. All modules should be compiled with the same -G num value."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On System V.4 and embedded PowerPC systems do (do not) emit register names in the assembly language output using symbolic forms."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "By default assume that all calls are far away so that a longer and more expensive calling sequence is required. This is required for calls farther than 32 megabytes (33,554,432 bytes) from the current location. A short call is generated if the compiler knows the call cannot be that far away. This setting can be overridden by the \"shortcall\" function attribute, or by #pragma longcall(0). Some linkers are capable of detecting out-of-range calls and generating glue code on the fly. On these systems, long calls are unnecessary and generate slower code. As of this writing, the AIX linker can do this, as can the GNU linker for PowerPC/64. It is planned to add this feature to the GNU linker for 32-bit PowerPC systems as well. On PowerPC64 ELFv2 and 32-bit PowerPC systems with newer GNU linkers, GCC can generate long calls using an inline PLT call sequence (see -mpltseq). PowerPC with -mbss-plt and PowerPC64 ELFv1 (big-endian) do not support inline PLT calls. On Darwin/PPC systems, \"#pragma longcall\" generates \"jbsr callee, L42\", plus a branch island (glue code). The two target addresses represent the callee and the branch island. The Darwin/PPC linker prefers the first address and generates a \"bl callee\" if the PPC \"bl\" instruction reaches the callee directly; otherwise, the linker generates \"bl L42\" to call the branch island. The branch island is appended to the body of the calling function; it computes the full 32-bit address of the callee and jumps to it. On Mach-O (Darwin) systems, this option directs the compiler emit to the glue for every direct call, and the Darwin linker decides whether to use or discard it. In the future, GCC may ignore all longcall specifications when the linker is known to generate glue."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Implement (do not implement) -fno-plt and long calls using an inline PLT call sequence that supports lazy linking and long calls to functions in dlopen'd shared libraries. Inline PLT calls are only supported on PowerPC64 ELFv2 and 32-bit PowerPC systems with newer GNU linkers, and are enabled by default if the support is detected when configuring GCC, and, in the case of 32-bit PowerPC, if GCC is configured with --enable-secureplt. -mpltseq code and -mbss-plt 32-bit PowerPC relocatable objects may not be linked together."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Mark (do not mark) calls to \"tlsgetaddr\" with a relocation specifying the function argument. The relocation allows the linker to reliably associate function call with argument setup instructions for TLS optimization, which in turn allows GCC to better schedule the sequence."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option enables use of the reciprocal estimate and reciprocal square root estimate instructions with additional Newton-Raphson steps to increase precision instead of doing a divide or square root and divide for floating-point arguments. You should use the -ffast-math option when using -mrecip (or at least -funsafe-math-optimizations, -ffinite-math-only, -freciprocal-math and -fno-trapping-math). Note that while the throughput of the sequence is generally higher than the throughput of the non-reciprocal instruction, the precision of the sequence can be decreased by up to 2 ulp (i.e. the inverse of 1.0 equals 0.99999994) for reciprocal square roots."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls which reciprocal estimate instructions may be used. opt is a comma- separated list of options, which may be preceded by a \"!\" to invert the option: all Enable all estimate instructions. default Enable the default instructions, equivalent to -mrecip. none Disable all estimate instructions, equivalent to -mno-recip. div Enable the reciprocal approximation instructions for both single and double precision. divf Enable the single-precision reciprocal approximation instructions. divd Enable the double-precision reciprocal approximation instructions. rsqrt Enable the reciprocal square root approximation instructions for both single and double precision. rsqrtf Enable the single-precision reciprocal square root approximation instructions. rsqrtd Enable the double-precision reciprocal square root approximation instructions. So, for example, -mrecip=all,!rsqrtd enables all of the reciprocal estimate instructions, except for the \"FRSQRTE\", \"XSRSQRTEDP\", and \"XVRSQRTEDP\" instructions which handle the double-precision reciprocal square root calculations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume (do not assume) that the reciprocal estimate instructions provide higher-precision estimates than is mandated by the PowerPC ABI. Selecting -mcpu=power6, -mcpu=power7 or -mcpu=power8 automatically selects -mrecip-precision. The double-precision square root estimate instructions are not generated by default on low-precision machines, since they do not provide an estimate that converges after three steps."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies the ABI type to use for vectorizing intrinsics using an external library. The only type supported at present is mass, which specifies to use IBM's Mathematical Acceleration Subsystem (MASS) libraries for vectorizing intrinsics using external libraries. GCC currently emits calls to \"acosd2\", \"acosf4\", \"acoshd2\", \"acoshf4\", \"asind2\", \"asinf4\", \"asinhd2\", \"asinhf4\", \"atan2d2\", \"atan2f4\", \"atand2\", \"atanf4\", \"atanhd2\", \"atanhf4\", \"cbrtd2\", \"cbrtf4\", \"cosd2\", \"cosf4\", \"coshd2\", \"coshf4\", \"erfcd2\", \"erfcf4\", \"erfd2\", \"erff4\", \"exp2d2\", \"exp2f4\", \"expd2\", \"expf4\", \"expm1d2\", \"expm1f4\", \"hypotd2\", \"hypotf4\", \"lgammad2\", \"lgammaf4\", \"log10d2\", \"log10f4\", \"log1pd2\", \"log1pf4\", \"log2d2\", \"log2f4\", \"logd2\", \"logf4\", \"powd2\", \"powf4\", \"sind2\", \"sinf4\", \"sinhd2\", \"sinhf4\", \"sqrtd2\", \"sqrtf4\", \"tand2\", \"tanf4\", \"tanhd2\", and \"tanhf4\" when generating code for power7. Both -ftree-vectorize and -funsafe-math-optimizations must also be enabled. The MASS libraries must be specified at link time."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) the \"friz\" instruction when the -funsafe-math-optimizations option is used to optimize rounding of floating-point values to 64-bit integer and back to floating point. The \"friz\" instruction does not return the same value if the floating-point number is too large to fit in an integer."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) code to load up the static chain register (\"r11\") when calling through a pointer on AIX and 64-bit Linux systems where a function pointer points to a 3-word descriptor giving the function address, TOC value to be loaded in register \"r2\", and static chain value to be loaded in register \"r11\". The -mpointers-to-nested-functions is on by default. You cannot call through pointers to nested functions or pointers to functions compiled in other languages that use the static chain if you use -mno-pointers-to-nested-functions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) code to save the TOC value in the reserved stack location in the function prologue if the function calls through a pointer on AIX and 64-bit Linux systems. If the TOC value is not saved in the prologue, it is saved just before the call through the pointer. The -mno-save-toc-indirect option is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) code to pass structure parameters with a maximum alignment of 64 bits, for compatibility with older versions of GCC. Older versions of GCC (prior to 4.9.0) incorrectly did not align a structure parameter on a 128-bit boundary when that structure contained a member requiring 128-bit alignment. This is corrected in more recent versions of GCC. This option may be used to generate code that is compatible with functions compiled with older versions of GCC. The -mno-compat-align-parm option is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate stack protection code using canary at guard. Supported locations are global for global canary or tls for per-thread canary in the TLS block (the default with GNU libc version 2.4 or later). With the latter choice the options -mstack-protector-guard-reg=reg and -mstack-protector-guard-offset=offset furthermore specify which register to use as base register for reading the canary, and from what offset from that base register. The default for those is as specified in the relevant ABI. -mstack-protector-guard-symbol=symbol overrides the offset with a symbol reference to a canary in the TLS block."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) pc-relative addressing. The -mpcrel option requires that the medium code model (-mcmodel=medium) and prefixed addressing (-mprefixed) options are enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) addressing modes using prefixed load and store instructions. The -mprefixed option requires that the option -mcpu=power10 (or later) is enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) the MMA instructions. The -mma option requires that the option -mcpu=power10 (or later) is enabled."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) ROP protection instructions when the target processor supports them. Currently this option disables the shrink-wrap optimization (-fshrink-wrap)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) code that will run in privileged state."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (do not generate) unaligned vsx loads and stores for inline expansion of \"memcpy\" and \"memmove\"."
        },
        {
            "flag": "",
            "long": "--param",
            "arg": null,
            "description": "The vectorizer will check with target information to determine whether it would be beneficial to unroll the main vectorized loop and by how much. This parameter sets the upper bound of how much the vectorizer will unroll the main loop. The default value is four. RX Options These command-line options are defined for RX targets:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Make the \"double\" data type be 64 bits (-m64bit-doubles) or 32 bits (-m32bit-doubles) in size. The default is -m32bit-doubles. Note RX floating-point hardware only works on 32-bit values, which is why the default is -m32bit-doubles."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enables (-fpu) or disables (-nofpu) the use of RX floating-point hardware. The default is enabled for the RX600 series and disabled for the RX200 series. Floating-point instructions are only generated for 32-bit floating-point values, however, so the FPU hardware is not used for doubles if the -m64bit-doubles option is used. Note If the -fpu option is enabled then -funsafe-math-optimizations is also enabled automatically. This is because the RX FPU instructions are themselves unsafe."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Selects the type of RX CPU to be targeted. Currently three types are supported, the generic RX600 and RX200 series hardware and the specific RX610 CPU. The default is RX600. The only difference between RX600 and RX610 is that the RX610 does not support the \"MVTIPL\" instruction. The RX200 series does not have a hardware floating-point unit and so -nofpu is enabled by default when this type is selected."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Store data (but not code) in the big-endian format. The default is -mlittle-endian-data, i.e. to store data in the little-endian format."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies the maximum size in bytes of global and static variables which can be placed into the small data area. Using the small data area can lead to smaller and faster code, but the size of area is limited and it is up to the programmer to ensure that the area does not overflow. Also when the small data area is used one of the RX's registers (usually \"r13\") is reserved for use pointing to this area, so it is no longer available for use by the compiler. This could result in slower and/or larger code if variables are pushed onto the stack instead of being held in this register. Note, common variables (variables that have not been initialized) and constants are not placed into the small data area as they are assigned to other sections in the output executable. The default value is zero, which disables this feature. Note, this feature is not enabled by default with higher optimization levels (-O2 etc) because of the potentially detrimental effects of reserving a register. It is up to the programmer to experiment and discover whether this feature is of benefit to their program. See the description of the -mpid option for a description of how the actual register to hold the small data area pointer is chosen."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use the simulator runtime. The default is to use the libgloss board-specific runtime."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When generating assembler output use a syntax that is compatible with Renesas's AS100 assembler. This syntax can also be handled by the GAS assembler, but it has some restrictions so it is not generated by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies the maximum size, in bytes, of a constant that can be used as an operand in a RX instruction. Although the RX instruction set does allow constants of up to 4 bytes in length to be used in instructions, a longer value equates to a longer instruction. Thus in some circumstances it can be beneficial to restrict the size of constants that are used in instructions. Constants that are too big are instead placed into a constant pool and referenced via register indirection. The value N can be between 0 and 4. A value of 0 (the default) or 4 means that constants of any size are allowed."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable linker relaxation. Linker relaxation is a process whereby the linker attempts to reduce the size of a program by finding shorter versions of various instructions. Disabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify the number of registers to reserve for fast interrupt handler functions. The value N can be between 0 and 4. A value of 1 means that register \"r13\" is reserved for the exclusive use of fast interrupt handlers. A value of 2 reserves \"r13\" and \"r12\". A value of 3 reserves \"r13\", \"r12\" and \"r11\", and a value of 4 reserves \"r13\" through \"r10\". A value of 0, the default, does not reserve any registers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies that interrupt handler functions should preserve the accumulator register. This is only necessary if normal code might use the accumulator register, for example because it performs 64-bit multiplications. The default is to ignore the accumulator as this makes the interrupt handlers faster."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enables the generation of position independent data. When enabled any access to constant data is done via an offset from a base address held in a register. This allows the location of constant data to be determined at run time without requiring the executable to be relocated, which is a benefit to embedded applications with tight memory constraints. Data that can be modified is not affected by this option. Note, using this feature reserves a register, usually \"r13\", for the constant data base address. This can result in slower and/or larger code, especially in complicated functions. The actual register chosen to hold the constant data base address depends upon whether the -msmall-data-limit and/or the -mint-register command-line options are enabled. Starting with register \"r13\" and proceeding downwards, registers are allocated first to satisfy the requirements of -mint-register, then -mpid and finally -msmall-data-limit. Thus it is possible for the small data area register to be \"r8\" if both -mint-register=4 and -mpid are specified on the command line. By default this feature is not enabled. The default can be restored via the -mno-pid command-line option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Prevents GCC from issuing a warning message if it finds more than one fast interrupt handler when it is compiling a file. The default is to issue a warning for each extra fast interrupt handler found, as the RX only supports one such interrupt."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enables or disables the use of the string manipulation instructions \"SMOVF\", \"SCMPU\", \"SMOVB\", \"SMOVU\", \"SUNTIL\" \"SWHILE\" and also the \"RMPA\" instruction. These instructions may prefetch data, which is not safe to do if accessing an I/O register. (See section 12.2.7 of the RX62N Group User's Manual for more information). The default is to allow these instructions, but it is not possible for GCC to reliably detect all circumstances where a string instruction might be used to access an I/O register, so their use cannot be disabled automatically. Instead it is reliant upon the programmer to use the -mno-allow-string-insns option if their program accesses I/O space. When the instructions are enabled GCC defines the C preprocessor symbol \"RXALLOWSTRINGINSNS\", otherwise it defines the symbol \"RXDISALLOWSTRINGINSNS\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use only (or not only) \"JSR\" instructions to access functions. This option can be used when code size exceeds the range of \"BSR\" instructions. Note that -mno-jsr does not mean to not use \"JSR\" but instead means that any type of branch may be used. Note: The generic GCC command-line option -ffixed-reg has special significance to the RX port when used with the \"interrupt\" function attribute. This attribute indicates a function intended to process fast interrupts. GCC ensures that it only uses the registers \"r10\", \"r11\", \"r12\" and/or \"r13\" and only provided that the normal use of the corresponding registers have been restricted via the -ffixed-reg or -mint-register command-line options. S/390 and zSeries Options These are the -m options defined for the S/390 and zSeries architecture."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) the hardware floating-point instructions and registers for floating- point operations. When -msoft-float is specified, functions in libgcc.a are used to perform floating-point operations. When -mhard-float is specified, the compiler generates IEEE floating-point instructions. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) the hardware decimal-floating-point instructions for decimal-floating- point operations. When -mno-hard-dfp is specified, functions in libgcc.a are used to perform decimal-floating-point operations. When -mhard-dfp is specified, the compiler generates decimal-floating-point hardware instructions. This is the default for -march=z9-ec or higher."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These switches control the size of \"long double\" type. A size of 64 bits makes the \"long double\" type equivalent to the \"double\" type. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Store (do not store) the address of the caller's frame as backchain pointer into the callee's stack frame. A backchain may be needed to allow debugging using tools that do not understand DWARF call frame information. When -mno-packed-stack is in effect, the backchain pointer is stored at the bottom of the stack frame; when -mpacked-stack is in effect, the backchain is placed into the topmost word of the 96/160 byte register save area. In general, code compiled with -mbackchain is call-compatible with code compiled with -mno-backchain; however, use of the backchain for debugging purposes usually requires that the whole binary is built with -mbackchain. Note that the combination of -mbackchain, -mpacked-stack and -mhard-float is not supported. In order to build a linux kernel use -msoft-float. The default is to not maintain the backchain."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use (do not use) the packed stack layout. When -mno-packed-stack is specified, the compiler uses the all fields of the 96/160 byte register save area only for their default purpose; unused fields still take up stack space. When -mpacked-stack is specified, register save slots are densely packed at the top of the register save area; unused space is reused for other purposes, allowing for more efficient use of the available stack space. However, when -mbackchain is also in effect, the topmost word of the save area is always used to store the backchain, and the return address register is always saved two words below the backchain. As long as the stack frame backchain is not used, code generated with -mpacked-stack is call-compatible with code generated with -mno-packed-stack. Note that some non-FSF releases of GCC 2.95 for S/390 or zSeries generated code that uses the stack frame backchain at run time, not just for debugging purposes. Such code is not call-compatible with code compiled with -mpacked-stack. Also, note that the combination of -mbackchain, -mpacked-stack and -mhard-float is not supported. In order to build a linux kernel use -msoft-float. The default is to not use the packed stack layout."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (or do not generate) code using the \"bras\" instruction to do subroutine calls. This only works reliably if the total executable size does not exceed 64k. The default is to use the \"basr\" instruction instead, which does not have this limitation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When -m31 is specified, generate code compliant to the GNU/Linux for S/390 ABI. When -m64 is specified, generate code compliant to the GNU/Linux for zSeries ABI. This allows GCC in particular to generate 64-bit instructions. For the s390 targets, the default is -m31, while the s390x targets default to -m64."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When -mzarch is specified, generate code using the instructions available on z/Architecture. When -mesa is specified, generate code using the instructions available on ESA/390. Note that -mesa is not possible with -m64. When generating code compliant to the GNU/Linux for S/390 ABI, the default is -mesa. When generating code compliant to the GNU/Linux for zSeries ABI, the default is -mzarch."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The -mhtm option enables a set of builtins making use of instructions available with the transactional execution facility introduced with the IBM zEnterprise EC12 machine generation S/390 System z Built-in Functions. -mhtm is enabled by default when using -march=zEC12."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When -mvx is specified, generate code using the instructions available with the vector extension facility introduced with the IBM z13 machine generation. This option changes the ABI for some vector type values with regard to alignment and calling conventions. In case vector type values are being used in an ABI-relevant context a GAS .gnuattribute command will be added to mark the resulting binary with the ABI used. -mvx is enabled by default when using -march=z13."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The -mzvector option enables vector language extensions and builtins using instructions available with the vector extension facility introduced with the IBM z13 machine generation. This option adds support for vector to be used as a keyword to define vector type variables and arguments. vector is only available when GNU extensions are enabled. It will not be expanded when requesting strict standard compliance e.g. with -std=c99. In addition to the GCC low-level builtins -mzvector enables a set of builtins added for compatibility with AltiVec-style implementations like Power and Cell. In order to make use of these builtins the header file vecintrin.h needs to be included. -mzvector is disabled by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate (or do not generate) code using the \"mvcle\" instruction to perform block moves. When -mno-mvcle is specified, use a \"mvc\" loop instead. This is the default unless optimizing for size."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Print (or do not print) additional debug information when compiling. The default is to not print debug information."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that runs on cpu-type, which is the name of a system representing a certain processor type. Possible values for cpu-type are z900/arch5, z990/arch6, z9-109, z9-ec/arch7, z10/arch8, z196/arch9, zEC12, z13/arch11, z14/arch12, z15/arch13, z16/arch14, and native. The default is -march=z900. Specifying native as cpu type can be used to select the best architecture option for the host processor. -march=native has no effect if GCC does not recognize the processor."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Tune to cpu-type everything applicable about the generated code, except for the ABI and the set of available instructions. The list of cpu-type values is the same as for -march. The default is the value used for -march."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that adds (does not add) in TPF OS specific branches to trace routines in the operating system. This option is off by default, even when compiling for the TPF OS."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that changes (does not change) the default branch targets enabled by -mtpf-trace to point to specialized trace routines providing the ability of selectively skipping function trace entries for the TPF OS. This option is off by default, even when compiling for the TPF OS and specifying -mtpf-trace."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses (does not use) the floating-point multiply and accumulate instructions. These instructions are generated by default if hardware floating point is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit a warning if the current function exceeds the given frame size. Because this is a compile-time check it doesn't need to be a real problem when the program runs. It is intended to identify functions that most probably cause a stack overflow. It is useful to be used in an environment with limited stack size e.g. the linux kernel."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit a warning if the function calls \"alloca\" or uses dynamically-sized arrays. This is generally a bad idea with a limited stack size."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If these options are provided the S/390 back end emits additional instructions in the function prologue that trigger a trap if the stack size is stack-guard bytes above the stack-size (remember that the stack on S/390 grows downward). If the stack-guard option is omitted the smallest power of 2 larger than the frame size of the compiled function is chosen. These options are intended to be used to help debugging stack overflow problems. The additionally emitted code causes only little overhead and hence can also be used in production-like systems without greater performance degradation. The given values have to be exact powers of 2 and stack-size has to be greater than stack-guard without exceeding 64k. In order to be efficient the extra code makes the assumption that the stack starts at an address aligned to the value given by stack-size. The stack-guard option can only be used in conjunction with stack-size."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If the hotpatch option is enabled, a \"hot-patching\" function prologue is generated for all functions in the compilation unit. The funtion label is prepended with the given number of two-byte NOP instructions (pre-halfwords, maximum 1000000). After the label, 2 * post-halfwords bytes are appended, using the largest NOP like instructions the architecture allows (maximum 1000000). If both arguments are zero, hotpatching is disabled. This option can be overridden for individual functions with the \"hotpatch\" attribute. SH Options These -m options are defined for the SH implementations:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the SH2e."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the SH2a without FPU, or for a SH2a-FPU in such a way that the floating-point unit is not used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the SH2a-FPU, in such a way that no double-precision floating-point operations are used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the SH2a-FPU assuming the floating-point unit is in single-precision mode by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the SH2a-FPU assuming the floating-point unit is in double-precision mode by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the SH3e."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the SH4 without a floating-point unit."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the SH4 with a floating-point unit that only supports single-precision arithmetic."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the SH4 assuming the floating-point unit is in single-precision mode by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for SH4-100."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for SH4-100 in such a way that the floating-point unit is not used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for SH4-100 assuming the floating-point unit is in single-precision mode by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for SH4-100 in such a way that no double-precision floating-point operations are used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for SH4-200."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for SH4-200 without in such a way that the floating-point unit is not used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for SH4-200 assuming the floating-point unit is in single-precision mode by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for SH4-200 in such a way that no double-precision floating-point operations are used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for SH4-300."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for SH4-300 without in such a way that the floating-point unit is not used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for SH4-300 in such a way that no double-precision floating-point operations are used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for SH4-300 in such a way that no double-precision floating-point operations are used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for SH4-340 (no MMU, no FPU)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for SH4-500 (no FPU). Passes -isa=sh4-nofpu to the assembler."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the SH4al-dsp, or for a SH4a in such a way that the floating-point unit is not used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the SH4a, in such a way that no double-precision floating-point operations are used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the SH4a assuming the floating-point unit is in single-precision mode by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the SH4a."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Same as -m4a-nofpu, except that it implicitly passes -dsp to the assembler. GCC doesn't generate any DSP instructions at the moment."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Align doubles at 64-bit boundaries. Note that this changes the calling conventions, and thus some functions from the standard C library do not work unless you recompile it first with -mdalign."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Shorten some address references at link time, when possible; uses the linker option -relax."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use 32-bit offsets in \"switch\" tables. The default is to use 16-bit offsets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the use of bit manipulation instructions on SH2A."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the use of the instruction \"fmovd\". Check -mdalign for alignment constraints."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Comply with the calling conventions defined by Renesas."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Comply with the calling conventions defined for GCC before the Renesas conventions were available. This option is the default for all targets of the SH toolchain."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Mark the \"MAC\" register as call-clobbered, even if -mrenesas is given."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Control the IEEE compliance of floating-point comparisons, which affects the handling of cases where the result of a comparison is unordered. By default -mieee is implicitly enabled. If -ffinite-math-only is enabled -mno-ieee is implicitly set, which results in faster floating-point greater-equal and less-equal comparisons. The implicit settings can be overridden by specifying either -mieee or -mno-ieee."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Inline code to invalidate instruction cache entries after setting up nested function trampolines. This option has no effect if -musermode is in effect and the selected code generation option (e.g. -m4) does not allow the use of the \"icbi\" instruction. If the selected code generation option does not allow the use of the \"icbi\" instruction, and -musermode is not in effect, the inlined code manipulates the instruction cache address array directly with an associative write. This not only requires privileged mode at run time, but it also fails if the cache line had been mapped via the TLB and has become unmapped."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Dump instruction size and location in the assembly code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is deprecated. It pads structures to multiple of 4 bytes, which is incompatible with the SH ABI."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Sets the model of atomic operations and additional parameters as a comma separated list. For details on the atomic built-in functions see atomic Builtins. The following models and parameters are supported: none Disable compiler generated atomic sequences and emit library calls for atomic operations. This is the default if the target is not \"sh*-*-linux*\". soft-gusa Generate GNU/Linux compatible gUSA software atomic sequences for the atomic built-in functions. The generated atomic sequences require additional support from the interrupt/exception handling code of the system and are only suitable for SH3* and SH4* single-core systems. This option is enabled by default when the target is \"sh*-*-linux*\" and SH3* or SH4*. When the target is SH4A, this option also partially utilizes the hardware atomic instructions \"movli.l\" and \"movco.l\" to create more efficient code, unless strict is specified. soft-tcb Generate software atomic sequences that use a variable in the thread control block. This is a variation of the gUSA sequences which can also be used on SH1* and SH2* targets. The generated atomic sequences require additional support from the interrupt/exception handling code of the system and are only suitable for single-core systems. When using this model, the gbr-offset= parameter has to be specified as well. soft-imask Generate software atomic sequences that temporarily disable interrupts by setting \"SR.IMASK = 1111\". This model works only when the program runs in privileged mode and is only suitable for single-core systems. Additional support from the interrupt/exception handling code of the system is not required. This model is enabled by default when the target is \"sh*-*-linux*\" and SH1* or SH2*. hard-llcs Generate hardware atomic sequences using the \"movli.l\" and \"movco.l\" instructions only. This is only available on SH4A and is suitable for multi-core systems. Since the hardware instructions support only 32 bit atomic variables access to 8 or 16 bit variables is emulated with 32 bit accesses. Code compiled with this option is also compatible with other software atomic model interrupt/exception handling systems if executed on an SH4A system. Additional support from the interrupt/exception handling code of the system is not required for this model. gbr-offset= This parameter specifies the offset in bytes of the variable in the thread control block structure that should be used by the generated atomic sequences when the soft- tcb model has been selected. For other models this parameter is ignored. The specified value must be an integer multiple of four and in the range 0-1020. strict This parameter prevents mixed usage of multiple atomic models, even if they are compatible, and makes the compiler generate atomic sequences of the specified model only."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate the \"tas.b\" opcode for \"atomictestandset\". Notice that depending on the particular hardware and software configuration this can degrade overall performance due to the operand cache line flushes that are implied by the \"tas.b\" instruction. On multi- core SH4A processors the \"tas.b\" instruction must be used with caution since it can result in data corruption for certain cache configurations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When generating position-independent code, emit function calls using the Global Offset Table instead of the Procedure Linkage Table."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't allow (allow) the compiler generating privileged mode code. Specifying -musermode also implies -mno-inline-icinvalidate if the inlined code would not work in user mode. -musermode is the default when the target is \"sh*-*-linux*\". If the target is SH1* or SH2* -musermode has no effect, since there is no user mode."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the cost to assume for a multiply insn."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the division strategy to be used for integer division operations. strategy can be one of: call-div1 Calls a library function that uses the single-step division instruction \"div1\" to perform the operation. Division by zero calculates an unspecified result and does not trap. This is the default except for SH4, SH2A and SHcompact. call-fp Calls a library function that performs the operation in double precision floating point. Division by zero causes a floating-point exception. This is the default for SHcompact with FPU. Specifying this for targets that do not have a double precision FPU defaults to \"call-div1\". call-table Calls a library function that uses a lookup table for small divisors and the \"div1\" instruction with case distinction for larger divisors. Division by zero calculates an unspecified result and does not trap. This is the default for SH4. Specifying this for targets that do not have dynamic shift instructions defaults to \"call-div1\". When a division strategy has not been specified the default strategy is selected based on the current target. For SH2A the default strategy is to use the \"divs\" and \"divu\" instructions instead of library function calls."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Reserve space once for outgoing arguments in the function prologue rather than around each call. Generally beneficial for performance and size. Also needed for unwinding to avoid changing the stack frame around conditional code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the name of the library function used for 32-bit signed division to name. This only affects the name used in the call division strategies, and the compiler still expects the same sets of input/output/clobbered registers as if this option were not present."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code treating the given register range as fixed registers. A fixed register is one that the register allocator cannot use. This is useful when compiling kernel code. A register range is specified as two registers separated by a dash. Multiple register ranges can be specified separated by a comma."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume num to be the cost for a branch instruction. Higher numbers make the compiler try to generate more branch-free code if possible. If not specified the value is selected depending on the processor type that is being compiled for."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume (do not assume) that zero displacement conditional branch instructions \"bt\" and \"bf\" are fast. If -mzdcbranch is specified, the compiler prefers zero displacement branch code sequences. This is enabled by default when generating code for SH4 and SH4A. It can be explicitly disabled by specifying -mno-zdcbranch."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force the usage of delay slots for conditional branches, which stuffs the delay slot with a \"nop\" if a suitable instruction cannot be found. By default this option is disabled. It can be enabled to work around hardware bugs as found in the original SH7055."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses (does not use) the floating-point multiply and accumulate instructions. These instructions are generated by default if hardware floating point is used. The machine-dependent -mfused-madd option is now mapped to the machine-independent -ffp-contract=fast option, and -mno-fused-madd is mapped to -ffp-contract=off."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow or disallow the compiler to emit the \"fsca\" instruction for sine and cosine approximations. The option -mfsca must be used in combination with -funsafe-math-optimizations. It is enabled by default when generating code for SH4A. Using -mno-fsca disables sine and cosine approximations even if -funsafe-math-optimizations is in effect."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Allow or disallow the compiler to emit the \"fsrra\" instruction for reciprocal square root approximations. The option -mfsrra must be used in combination with -funsafe-math-optimizations and -ffinite-math-only. It is enabled by default when generating code for SH4A. Using -mno-fsrra disables reciprocal square root approximations even if -funsafe-math-optimizations and -ffinite-math-only are in effect."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Prefer zero-displacement conditional branches for conditional move instruction patterns. This can result in faster code on the SH4 processor."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code using the FDPIC ABI. Solaris 2 Options These -m options are supported on Solaris 2:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "-mclear-hwcap tells the compiler to remove the hardware capabilities generated by the Solaris assembler. This is only necessary when object files use ISA extensions not supported by the current machine, but check at runtime whether or not to use them."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "-mimpure-text, used in addition to -shared, tells the compiler to not pass -z text to the linker when linking a shared object. Using this option, you can link position-dependent code into a shared object. -mimpure-text suppresses the \"relocations remain against allocatable but non-writable sections\" linker error message. However, the necessary relocations trigger copy-on- write, and the shared object is not actually shared across processes. Instead of using -mimpure-text, you should compile all source code with -fpic or -fPIC. These switches are supported in addition to the above on Solaris 2:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This is a synonym for -pthread. SPARC Options These -m options are supported on the SPARC:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify -mapp-regs to generate output using the global registers 2 through 4, which the SPARC SVR4 ABI reserves for applications. Like the global register 1, each global register 2 through 4 is then treated as an allocable register that is clobbered by function calls. This is the default. To be fully SVR4 ABI-compliant at the cost of some performance loss, specify -mno-app-regs. You should compile libraries and system software with this option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -mflat, the compiler does not generate save/restore instructions and uses a \"flat\" or single register window model. This model is compatible with the regular register window model. The local registers and the input registers (0--5) are still treated as \"call-saved\" registers and are saved on the stack as needed. With -mno-flat (the default), the compiler generates save/restore instructions (except for leaf functions). This is the normal operating mode."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output containing floating-point instructions. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output containing library calls for floating point. Warning: the requisite libraries are not available for all SPARC targets. Normally the facilities of the machine's usual C compiler are used, but this cannot be done directly in cross- compilation. You must make your own arrangements to provide suitable library functions for cross-compilation. The embedded targets sparc-*-aout and sparclite-*-* do provide software floating-point support. -msoft-float changes the calling convention in the output file; therefore, it is only useful if you compile all of a program with this option. In particular, you need to compile libgcc.a, the library that comes with GCC, with -msoft-float in order for this to work."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output containing quad-word (long double) floating-point instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output containing library calls for quad-word (long double) floating-point instructions. The functions called are those specified in the SPARC ABI. This is the default. As of this writing, there are no SPARC implementations that have hardware support for the quad-word floating-point instructions. They all invoke a trap handler for one of these instructions, and then the trap handler emulates the effect of the instruction. Because of the trap handler overhead, this is much slower than calling the ABI library routines. Thus the -msoft-quad-float option is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume that doubles have 8-byte alignment. This is the default. With -munaligned-doubles, GCC assumes that doubles have 8-byte alignment only if they are contained in another type, or if they have an absolute address. Otherwise, it assumes they have 4-byte alignment. Specifying this option avoids some rare compatibility problems with code generated by other compilers. It is not the default because it results in a performance loss, especially for floating-point code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not generate code that can only run in supervisor mode. This is relevant only for the \"casa\" instruction emitted for the LEON3 processor. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -mfaster-structs, the compiler assumes that structures should have 8-byte alignment. This enables the use of pairs of \"ldd\" and \"std\" instructions for copies in structure assignment, in place of twice as many \"ld\" and \"st\" pairs. However, the use of this changed alignment directly violates the SPARC ABI. Thus, it's intended only for use on targets where the developer acknowledges that their resulting code is not directly in line with the rules of the ABI."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -mstd-struct-return, the compiler generates checking code in functions returning structures or unions to detect size mismatches between the two sides of function calls, as per the 32-bit ABI. The default is -mno-std-struct-return. This option has no effect in 64-bit mode."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable Local Register Allocation. This is the default for SPARC since GCC 7 so -mno-lra needs to be passed to get old Reload."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the instruction set, register set, and instruction scheduling parameters for machine type cputype. Supported values for cputype are v7, cypress, v8, supersparc, hypersparc, leon, leon3, leon3v7, leon5, sparclite, f930, f934, sparclite86x, sparclet, tsc701, v9, ultrasparc, ultrasparc3, niagara, niagara2, niagara3, niagara4, niagara7 and m8. Native Solaris and GNU/Linux toolchains also support the value native, which selects the best architecture option for the host processor. -mcpu=native has no effect if GCC does not recognize the processor. Default instruction scheduling parameters are used for values that select an architecture and not an implementation. These are v7, v8, sparclite, sparclet, v9. Here is a list of each supported architecture and their supported implementations. v7 cypress, leon3v7 v8 supersparc, hypersparc, leon, leon3, leon5 sparclite f930, f934, sparclite86x sparclet tsc701 v9 ultrasparc, ultrasparc3, niagara, niagara2, niagara3, niagara4, niagara7, m8 By default (unless configured otherwise), GCC generates code for the V7 variant of the SPARC architecture. With -mcpu=cypress, the compiler additionally optimizes it for the Cypress CY7C602 chip, as used in the SPARCStation/SPARCServer 3xx series. This is also appropriate for the older SPARCStation 1, 2, IPX etc. With -mcpu=v8, GCC generates code for the V8 variant of the SPARC architecture. The only difference from V7 code is that the compiler emits the integer multiply and integer divide instructions which exist in SPARC-V8 but not in SPARC-V7. With -mcpu=supersparc, the compiler additionally optimizes it for the SuperSPARC chip, as used in the SPARCStation 10, 1000 and 2000 series. With -mcpu=sparclite, GCC generates code for the SPARClite variant of the SPARC architecture. This adds the integer multiply, integer divide step and scan (\"ffs\") instructions which exist in SPARClite but not in SPARC-V7. With -mcpu=f930, the compiler additionally optimizes it for the Fujitsu MB86930 chip, which is the original SPARClite, with no FPU. With -mcpu=f934, the compiler additionally optimizes it for the Fujitsu MB86934 chip, which is the more recent SPARClite with FPU. With -mcpu=sparclet, GCC generates code for the SPARClet variant of the SPARC architecture. This adds the integer multiply, multiply/accumulate, integer divide step and scan (\"ffs\") instructions which exist in SPARClet but not in SPARC-V7. With -mcpu=tsc701, the compiler additionally optimizes it for the TEMIC SPARClet chip. With -mcpu=v9, GCC generates code for the V9 variant of the SPARC architecture. This adds 64-bit integer and floating-point move instructions, 3 additional floating-point condition code registers and conditional move instructions. With -mcpu=ultrasparc, the compiler additionally optimizes it for the Sun UltraSPARC I/II/IIi chips. With -mcpu=ultrasparc3, the compiler additionally optimizes it for the Sun UltraSPARC III/III+/IIIi/IIIi+/IV/IV+ chips. With -mcpu=niagara, the compiler additionally optimizes it for Sun UltraSPARC T1 chips. With -mcpu=niagara2, the compiler additionally optimizes it for Sun UltraSPARC T2 chips. With -mcpu=niagara3, the compiler additionally optimizes it for Sun UltraSPARC T3 chips. With -mcpu=niagara4, the compiler additionally optimizes it for Sun UltraSPARC T4 chips. With -mcpu=niagara7, the compiler additionally optimizes it for Oracle SPARC M7 chips. With -mcpu=m8, the compiler additionally optimizes it for Oracle M8 chips."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the instruction scheduling parameters for machine type cputype, but do not set the instruction set or register set that the option -mcpu=cputype does. The same values for -mcpu=cputype can be used for -mtune=cputype, but the only useful values are those that select a particular CPU implementation. Those are cypress, supersparc, hypersparc, leon, leon3, leon3v7, leon5, f930, f934, sparclite86x, tsc701, ultrasparc, ultrasparc3, niagara, niagara2, niagara3, niagara4, niagara7 and m8. With native Solaris and GNU/Linux toolchains, native can also be used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -mv8plus, GCC generates code for the SPARC-V8+ ABI. The difference from the V8 ABI is that the global and out registers are considered 64 bits wide. This is enabled by default on Solaris in 32-bit mode for all SPARC-V9 processors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -mvis, GCC generates code that takes advantage of the UltraSPARC Visual Instruction Set extensions. The default is -mno-vis."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -mvis2, GCC generates code that takes advantage of version 2.0 of the UltraSPARC Visual Instruction Set extensions. The default is -mvis2 when targeting a cpu that supports such instructions, such as UltraSPARC-III and later. Setting -mvis2 also sets -mvis."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -mvis3, GCC generates code that takes advantage of version 3.0 of the UltraSPARC Visual Instruction Set extensions. The default is -mvis3 when targeting a cpu that supports such instructions, such as niagara-3 and later. Setting -mvis3 also sets -mvis2 and -mvis."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -mvis4, GCC generates code that takes advantage of version 4.0 of the UltraSPARC Visual Instruction Set extensions. The default is -mvis4 when targeting a cpu that supports such instructions, such as niagara-7 and later. Setting -mvis4 also sets -mvis3, -mvis2 and -mvis."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -mvis4b, GCC generates code that takes advantage of version 4.0 of the UltraSPARC Visual Instruction Set extensions, plus the additional VIS instructions introduced in the Oracle SPARC Architecture 2017. The default is -mvis4b when targeting a cpu that supports such instructions, such as m8 and later. Setting -mvis4b also sets -mvis4, -mvis3, -mvis2 and -mvis."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -mcbcond, GCC generates code that takes advantage of the UltraSPARC Compare-and- Branch-on-Condition instructions. The default is -mcbcond when targeting a CPU that supports such instructions, such as Niagara-4 and later."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -mfmaf, GCC generates code that takes advantage of the UltraSPARC Fused Multiply-Add Floating-point instructions. The default is -mfmaf when targeting a CPU that supports such instructions, such as Niagara-3 and later."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -mfsmuld, GCC generates code that takes advantage of the Floating-point Multiply Single to Double (FsMULd) instruction. The default is -mfsmuld when targeting a CPU supporting the architecture versions V8 or V9 with FPU except -mcpu=leon."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -mpopc, GCC generates code that takes advantage of the UltraSPARC Population Count instruction. The default is -mpopc when targeting a CPU that supports such an instruction, such as Niagara-2 and later."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -msubxc, GCC generates code that takes advantage of the UltraSPARC Subtract- Extended-with-Carry instruction. The default is -msubxc when targeting a CPU that supports such an instruction, such as Niagara-7 and later."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the documented workaround for the single erratum of the Atmel AT697F processor (which corresponds to erratum #13 of the AT697E processor)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the documented workarounds for the floating-point errata and the data cache nullify errata of the UT699 processor."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the documented workaround for the back-to-back store errata of the UT699E/UT700 processor."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable the documented workaround for the back-to-back store errata of the GR712RC processor. These -m options are supported in addition to the above on SPARC-V9 processors in 64-bit environments:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a 32-bit or 64-bit environment. The 32-bit environment sets int, long and pointer to 32 bits. The 64-bit environment sets int to 32 bits and long and pointer to 64 bits."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the code model to one of medlow The Medium/Low code model: 64-bit addresses, programs must be linked in the low 32 bits of memory. Programs can be statically or dynamically linked. medmid The Medium/Middle code model: 64-bit addresses, programs must be linked in the low 44 bits of memory, the text and data segments must be less than 2GB in size and the data segment must be located within 2GB of the text segment. medany The Medium/Anywhere code model: 64-bit addresses, programs may be linked anywhere in memory, the text and data segments must be less than 2GB in size and the data segment must be located within 2GB of the text segment. embmedany The Medium/Anywhere code model for embedded systems: 64-bit addresses, the text and data segments must be less than 2GB in size, both starting anywhere in memory (determined at link time). The global register %g4 points to the base of the data segment. Programs are statically linked and PIC is not supported."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the memory model in force on the processor to one of default The default memory model for the processor and operating system. rmo Relaxed Memory Order pso Partial Store Order tso Total Store Order sc Sequential Consistency These memory models are formally defined in Appendix D of the SPARC-V9 architecture manual, as set in the processor's \"PSTATE.MM\" field."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "With -mstack-bias, GCC assumes that the stack pointer, and frame pointer if present, are offset by -2047 which must be added back when making stack frame references. This is the default in 64-bit mode. Otherwise, assume no such offset is present. Options for System V These additional options are available on System V Release 4 for compatibility with other compilers on those systems:"
        },
        {
            "flag": "-G",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "directive in the output."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Search the directories dirs, and no others, for libraries specified with -l."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Look in the directory dir to find the M4 preprocessor. The assembler uses this option. V850 Options These -m options are defined for V850 implementations:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Treat all calls as being far away (near). If calls are assumed to be far away, the compiler always loads the function's address into a register, and calls indirect through the pointer."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not optimize (do optimize) basic blocks that use the same index pointer 4 or more times to copy pointer into the \"ep\" register, and use the shorter \"sld\" and \"sst\" instructions. The -mep option is on by default if you optimize."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use (do use) external functions to save and restore registers at the prologue and epilogue of a function. The external functions are slower, but use less code space if more than one function saves the same number of registers. The -mprolog-function option is on by default if you optimize."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Try to make the code as small as possible. At present, this just turns on the -mep and -mprolog-function options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Put static or global variables whose size is n bytes or less into the tiny data area that register \"ep\" points to. The tiny data area can hold up to 256 bytes in total (128 bytes for byte references)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Put static or global variables whose size is n bytes or less into the small data area that register \"gp\" points to. The small data area can hold up to 64 kilobytes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Put static or global variables whose size is n bytes or less into the first 32 kilobytes of memory."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify that the target processor is the V850."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify that the target processor is the V850E3V5. The preprocessor constant \"v850e3v5\" is defined if this option is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify that the target processor is the V850E3V5. This is an alias for the -mv850e3v5 option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify that the target processor is the V850E2V3. The preprocessor constant \"v850e2v3\" is defined if this option is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify that the target processor is the V850E2. The preprocessor constant \"v850e2\" is defined if this option is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify that the target processor is the V850E1. The preprocessor constants \"v850e1\" and \"v850e\" are defined if this option is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify that the target processor is the V850ES. This is an alias for the -mv850e1 option."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify that the target processor is the V850E. The preprocessor constant \"v850e\" is defined if this option is used. If neither -mv850 nor -mv850e nor -mv850e1 nor -mv850e2 nor -mv850e2v3 nor -mv850e3v5 are defined then a default target processor is chosen and the relevant v850* preprocessor constant is defined. The preprocessor constants \"v850\" and \"v851\" are always defined, regardless of which processor variant is the target."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option suppresses generation of the \"CALLT\" instruction for the v850e, v850e1, v850e2, v850e2v3 and v850e3v5 flavors of the v850 architecture. This option is enabled by default when the RH850 ABI is in use (see -mrh850-abi), and disabled by default when the GCC ABI is in use. If \"CALLT\" instructions are being generated then the C preprocessor symbol \"V850CALLT\" is defined."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Pass on (or do not pass on) the -mrelax command-line option to the assembler."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable (or re-enable) the generation of PC-relative jump instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable (or re-enable) the generation of hardware floating point instructions. This option is only significant when the target architecture is V850E2V3 or higher. If hardware floating point instructions are being generated then the C preprocessor symbol \"FPUOK\" is defined, otherwise the symbol \"NOFPU\" is defined."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enables the use of the e3v5 LOOP instruction. The use of this instruction is not enabled by default when the e3v5 architecture is selected because its use is still experimental."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enables support for the RH850 version of the V850 ABI. This is the default. With this version of the ABI the following rules apply: * Integer sized structures and unions are returned via a memory pointer rather than a register. * Large structures and unions (more than 8 bytes in size) are passed by value. * Functions are aligned to 16-bit boundaries. * The -m8byte-align command-line option is supported. * The -mdisable-callt command-line option is enabled by default. The -mno-disable-callt command-line option is not supported. When this version of the ABI is enabled the C preprocessor symbol \"V850RH850ABI\" is defined."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enables support for the old GCC version of the V850 ABI. With this version of the ABI the following rules apply: * Integer sized structures and unions are returned in register \"r10\". * Large structures and unions (more than 8 bytes in size) are passed by reference. * Functions are aligned to 32-bit boundaries, unless optimizing for size. * The -m8byte-align command-line option is not supported. * The -mdisable-callt command-line option is supported but not enabled by default. When this version of the ABI is enabled the C preprocessor symbol \"V850GCCABI\" is defined."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enables support for \"double\" and \"long long\" types to be aligned on 8-byte boundaries. The default is to restrict the alignment of all objects to at most 4-bytes. When -m8byte-align is in effect the C preprocessor symbol \"V8508BYTEALIGN\" is defined."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code suitable for big switch tables. Use this option only if the assembler/linker complain about out of range branches within a switch table."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option causes r2 and r5 to be used in the code generated by the compiler. This setting is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option causes r2 and r5 to be treated as fixed registers. VAX Options These -m options are defined for the VAX:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not output certain jump instructions (\"aobleq\" and so on) that the Unix assembler for the VAX cannot handle across long ranges."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do output those jump instructions, on the assumption that the GNU assembler is being used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable Local Register Allocation. This is still experimental for the VAX, so by default the compiler uses standard reload. Visium Options"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "A program which performs file I/O and is destined to run on an MCM target should be linked with this option. It causes the libraries libc.a and libdebug.a to be linked. The program should be run on the target under the control of the GDB remote debugging stub."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "A program which performs file I/O and is destined to run on the simulator should be linked with option. This causes libraries libc.a and libsim.a to be linked."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code containing floating-point instructions. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code containing library calls for floating-point. -msoft-float changes the calling convention in the output file; therefore, it is only useful if you compile all of a program with this option. In particular, you need to compile libgcc.a, the library that comes with GCC, with -msoft-float in order for this to work."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the instruction set, register set, and instruction scheduling parameters for machine type cputype. Supported values for cputype are mcm, gr5 and gr6. mcm is a synonym of gr5 present for backward compatibility. By default (unless configured otherwise), GCC generates code for the GR5 variant of the Visium architecture. With -mcpu=gr6, GCC generates code for the GR6 variant of the Visium architecture. The only difference from GR5 code is that the compiler will generate block move instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the instruction scheduling parameters for machine type cputype, but do not set the instruction set or register set that the option -mcpu=cputype would."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the supervisor mode, where there are no restrictions on the access to general registers. This is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the user mode, where the access to some general registers is forbidden: on the GR5, registers r24 to r31 cannot be accessed in this mode; on the GR6, only registers r29 to r31 are affected. VMS Options These -m options are defined for the VMS implementations:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Return VMS condition codes from \"main\". The default is to return POSIX-style condition (e.g. error) codes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Flag the first routine whose name starts with prefix as the main routine for the debugger."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Default to 64-bit memory allocation routines."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set the default size of pointers. Possible options for size are 32 or short for 32 bit pointers, 64 or long for 64 bit pointers, and no for supporting only 32 bit pointers. The later option disables \"pragma pointersize\". VxWorks Options The options in this section are defined for all VxWorks targets. Options specific to the target hardware are listed with the other options for that target."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "GCC can generate code for both VxWorks kernels and real time processes (RTPs). This option switches from the former to the latter. It also defines the preprocessor macro \"RTP\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Link an RTP executable against shared libraries rather than static libraries. The options -static and -shared can also be used for RTPs; -static is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These options are passed down to the linker. They are defined for compatibility with Diab."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable lazy binding of function calls. This option is equivalent to -Wl,-z,now and is defined for compatibility with Diab."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Disable lazy binding of function calls. This option is the default and is defined for compatibility with Diab. x86 Options These -m options are defined for the x86 family of computers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate instructions for the machine type cpu-type. In contrast to -mtune=cpu-type, which merely tunes the generated code for the specified cpu-type, -march=cpu-type allows GCC to generate code that may not run at all on processors other than the one indicated. Specifying -march=cpu-type implies -mtune=cpu-type, except where noted otherwise. The choices for cpu-type are: native This selects the CPU to generate code for at compilation time by determining the processor type of the compiling machine. Using -march=native enables all instruction subsets supported by the local machine (hence the result might not run on different machines). Using -mtune=native produces code optimized for the local machine under the constraints of the selected instruction set. x86-64 A generic CPU with 64-bit extensions. x86-64-v2 x86-64-v3 x86-64-v4 These choices for cpu-type select the corresponding micro-architecture level from the x86-64 psABI. On ABIs other than the x86-64 psABI they select the same CPU features as the x86-64 psABI documents for the particular micro-architecture level. Since these cpu-type values do not have a corresponding -mtune setting, using -march with these values enables generic tuning. Specific tuning can be enabled using the -mtune=other-cpu-type option with an appropriate other-cpu-type value. i386 Original Intel i386 CPU. i486 Intel i486 CPU. (No scheduling is implemented for this chip.) i586 pentium Intel Pentium CPU with no MMX support. lakemont Intel Lakemont MCU, based on Intel Pentium CPU. pentium-mmx Intel Pentium MMX CPU, based on Pentium core with MMX instruction set support. pentiumpro Intel Pentium Pro CPU. i686 When used with -march, the Pentium Pro instruction set is used, so the code runs on all i686 family chips. When used with -mtune, it has the same meaning as generic. pentium2 Intel Pentium II CPU, based on Pentium Pro core with MMX and FXSR instruction set support. pentium3 pentium3m Intel Pentium III CPU, based on Pentium Pro core with MMX, FXSR and SSE instruction set support. pentium-m Intel Pentium M; low-power version of Intel Pentium III CPU with MMX, SSE, SSE2 and FXSR instruction set support. Used by Centrino notebooks. pentium4 pentium4m Intel Pentium 4 CPU with MMX, SSE, SSE2 and FXSR instruction set support. prescott Improved version of Intel Pentium 4 CPU with MMX, SSE, SSE2, SSE3 and FXSR instruction set support. nocona Improved version of Intel Pentium 4 CPU with 64-bit extensions, MMX, SSE, SSE2, SSE3 and FXSR instruction set support. core2 Intel Core 2 CPU with 64-bit extensions, MMX, SSE, SSE2, SSE3, SSSE3, CX16, SAHF and FXSR instruction set support. nehalem Intel Nehalem CPU with 64-bit extensions, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF and FXSR instruction set support. westmere Intel Westmere CPU with 64-bit extensions, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR and PCLMUL instruction set support. sandybridge Intel Sandy Bridge CPU with 64-bit extensions, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE and PCLMUL instruction set support. ivybridge Intel Ivy Bridge CPU with 64-bit extensions, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND and F16C instruction set support. haswell Intel Haswell CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE and HLE instruction set support. broadwell Intel Broadwell CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX and PREFETCHW instruction set support. skylake Intel Skylake CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AES, CLFLUSHOPT, XSAVEC, XSAVES and SGX instruction set support. bonnell Intel Bonnell CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3 and SSSE3 instruction set support. silvermont Intel Silvermont CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, PCLMUL, PREFETCHW and RDRND instruction set support. goldmont Intel Goldmont CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, PCLMUL, PREFETCHW, RDRND, AES, SHA, RDSEED, XSAVE, XSAVEC, XSAVES, XSAVEOPT, CLFLUSHOPT and FSGSBASE instruction set support. goldmont-plus Intel Goldmont Plus CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, PCLMUL, PREFETCHW, RDRND, AES, SHA, RDSEED, XSAVE, XSAVEC, XSAVES, XSAVEOPT, CLFLUSHOPT, FSGSBASE, PTWRITE, RDPID and SGX instruction set support. tremont Intel Tremont CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, PCLMUL, PREFETCHW, RDRND, AES, SHA, RDSEED, XSAVE, XSAVEC, XSAVES, XSAVEOPT, CLFLUSHOPT, FSGSBASE, PTWRITE, RDPID, SGX, CLWB, GFNI-SSE, MOVDIRI, MOVDIR64B, CLDEMOTE and WAITPKG instruction set support. sierraforest Intel Sierra Forest CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, AES, PREFETCHW, PCLMUL, RDRND, XSAVE, XSAVEC, XSAVES, XSAVEOPT, FSGSBASE, PTWRITE, RDPID, SGX, GFNI-SSE, CLWB, MOVDIRI, MOVDIR64B, CLDEMOTE, WAITPKG, ADCX, AVX, AVX2, BMI, BMI2, F16C, FMA, LZCNT, PCONFIG, PKU, VAES, VPCLMULQDQ, SERIALIZE, HRESET, KL, WIDEKL, AVX-VNNI, AVXIFMA, AVXVNNIINT8, AVXNECONVERT, CMPCCXADD, ENQCMD and UINTR instruction set support. grandridge Intel Grand Ridge CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, AES, PREFETCHW, PCLMUL, RDRND, XSAVE, XSAVEC, XSAVES, XSAVEOPT, FSGSBASE, PTWRITE, RDPID, SGX, GFNI-SSE, CLWB, MOVDIRI, MOVDIR64B, CLDEMOTE, WAITPKG, ADCX, AVX, AVX2, BMI, BMI2, F16C, FMA, LZCNT, PCONFIG, PKU, VAES, VPCLMULQDQ, SERIALIZE, HRESET, KL, WIDEKL, AVX-VNNI, AVXIFMA, AVXVNNIINT8, AVXNECONVERT, CMPCCXADD, ENQCMD and UINTR instruction set support. knl Intel Knight's Landing CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AVX512PF, AVX512ER, AVX512F, AVX512CD and PREFETCHWT1 instruction set support. knm Intel Knights Mill CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AVX512PF, AVX512ER, AVX512F, AVX512CD and PREFETCHWT1, AVX5124VNNIW, AVX5124FMAPS and AVX512VPOPCNTDQ instruction set support. skylake-avx512 Intel Skylake Server CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AES, CLFLUSHOPT, XSAVEC, XSAVES, SGX, AVX512F, CLWB, AVX512VL, AVX512BW, AVX512DQ and AVX512CD instruction set support. cannonlake Intel Cannonlake Server CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AES, CLFLUSHOPT, XSAVEC, XSAVES, SGX, AVX512F, AVX512VL, AVX512BW, AVX512DQ, AVX512CD, PKU, AVX512VBMI, AVX512IFMA and SHA instruction set support. icelake-client Intel Icelake Client CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AES, CLFLUSHOPT, XSAVEC, XSAVES, SGX, AVX512F, AVX512VL, AVX512BW, AVX512DQ, AVX512CD, PKU, AVX512VBMI, AVX512IFMA, SHA, AVX512VNNI, GFNI, VAES, AVX512VBMI2 , VPCLMULQDQ, AVX512BITALG, RDPID and AVX512VPOPCNTDQ instruction set support. icelake-server Intel Icelake Server CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AES, CLFLUSHOPT, XSAVEC, XSAVES, SGX, AVX512F, AVX512VL, AVX512BW, AVX512DQ, AVX512CD, PKU, AVX512VBMI, AVX512IFMA, SHA, AVX512VNNI, GFNI, VAES, AVX512VBMI2 , VPCLMULQDQ, AVX512BITALG, RDPID, AVX512VPOPCNTDQ, PCONFIG, WBNOINVD and CLWB instruction set support. cascadelake Intel Cascadelake CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AES, CLFLUSHOPT, XSAVEC, XSAVES, SGX, AVX512F, CLWB, AVX512VL, AVX512BW, AVX512DQ, AVX512CD and AVX512VNNI instruction set support. cooperlake Intel cooperlake CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AES, CLFLUSHOPT, XSAVEC, XSAVES, SGX, AVX512F, CLWB, AVX512VL, AVX512BW, AVX512DQ, AVX512CD, AVX512VNNI and AVX512BF16 instruction set support. tigerlake Intel Tigerlake CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AES, CLFLUSHOPT, XSAVEC, XSAVES, SGX, AVX512F, AVX512VL, AVX512BW, AVX512DQ, AVX512CD PKU, AVX512VBMI, AVX512IFMA, SHA, AVX512VNNI, GFNI, VAES, AVX512VBMI2, VPCLMULQDQ, AVX512BITALG, RDPID, AVX512VPOPCNTDQ, MOVDIRI, MOVDIR64B, CLWB, AVX512VP2INTERSECT and KEYLOCKER instruction set support. sapphirerapids Intel sapphirerapids CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AES, CLFLUSHOPT, XSAVEC, XSAVES, SGX, AVX512F, AVX512VL, AVX512BW, AVX512DQ, AVX512CD, PKU, AVX512VBMI, AVX512IFMA, SHA, AVX512VNNI, GFNI, VAES, AVX512VBMI2, VPCLMULQDQ, AVX512BITALG, RDPID, AVX512VPOPCNTDQ, PCONFIG, WBNOINVD, CLWB, MOVDIRI, MOVDIR64B, ENQCMD, CLDEMOTE, PTWRITE, WAITPKG, SERIALIZE, TSXLDTRK, UINTR, AMX-BF16, AMX-TILE, AMX-INT8, AVX-VNNI, AVX512-FP16 and AVX512BF16 instruction set support. alderlake Intel Alderlake CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, AES, PREFETCHW, PCLMUL, RDRND, XSAVE, XSAVEC, XSAVES, XSAVEOPT, FSGSBASE, PTWRITE, RDPID, SGX, GFNI-SSE, CLWB, MOVDIRI, MOVDIR64B, CLDEMOTE, WAITPKG, ADCX, AVX, AVX2, BMI, BMI2, F16C, FMA, LZCNT, PCONFIG, PKU, VAES, VPCLMULQDQ, SERIALIZE, HRESET, KL, WIDEKL and AVX-VNNI instruction set support. rocketlake Intel Rocketlake CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3 , SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AES, CLFLUSHOPT, XSAVEC, XSAVES, AVX512F, AVX512VL, AVX512BW, AVX512DQ, AVX512CD PKU, AVX512VBMI, AVX512IFMA, SHA, AVX512VNNI, GFNI, VAES, AVX512VBMI2, VPCLMULQDQ, AVX512BITALG, RDPID and AVX512VPOPCNTDQ instruction set support. graniterapids Intel graniterapids CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AES, CLFLUSHOPT, XSAVEC, XSAVES, SGX, AVX512F, AVX512VL, AVX512BW, AVX512DQ, AVX512CD, PKU, AVX512VBMI, AVX512IFMA, SHA, AVX512VNNI, GFNI, VAES, AVX512VBMI2, VPCLMULQDQ, AVX512BITALG, RDPID, AVX512VPOPCNTDQ, PCONFIG, WBNOINVD, CLWB, MOVDIRI, MOVDIR64B, ENQCMD, CLDEMOTE, PTWRITE, WAITPKG, SERIALIZE, TSXLDTRK, UINTR, AMX-BF16, AMX-TILE, AMX-INT8, AVX-VNNI, AVX512-FP16, AVX512BF16, AMX-FP16 and PREFETCHI instruction set support. graniterapids-d Intel graniterapids D CPU with 64-bit extensions, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, POPCNT, CX16, SAHF, FXSR, AVX, XSAVE, PCLMUL, FSGSBASE, RDRND, F16C, AVX2, BMI, BMI2, LZCNT, FMA, MOVBE, HLE, RDSEED, ADCX, PREFETCHW, AES, CLFLUSHOPT, XSAVEC, XSAVES, SGX, AVX512F, AVX512VL, AVX512BW, AVX512DQ, AVX512CD, PKU, AVX512VBMI, AVX512IFMA, SHA, AVX512VNNI, GFNI, VAES, AVX512VBMI2, VPCLMULQDQ, AVX512BITALG, RDPID, AVX512VPOPCNTDQ, PCONFIG, WBNOINVD, CLWB, MOVDIRI, MOVDIR64B, ENQCMD, CLDEMOTE, PTWRITE, WAITPKG, SERIALIZE, TSXLDTRK, UINTR, AMX-BF16, AMX-TILE, AMX-INT8, AVX-VNNI, AVX512FP16, AVX512BF16, AMX-FP16, PREFETCHI and AMX-COMPLEX instruction set support. k6 AMD K6 CPU with MMX instruction set support. k6-2 k6-3 Improved versions of AMD K6 CPU with MMX and 3DNow! instruction set support. athlon athlon-tbird AMD Athlon CPU with MMX, 3dNOW!, enhanced 3DNow! and SSE prefetch instructions support. athlon-4 athlon-xp athlon-mp Improved AMD Athlon CPU with MMX, 3DNow!, enhanced 3DNow! and full SSE instruction set support. k8 opteron athlon64 athlon-fx Processors based on the AMD K8 core with x86-64 instruction set support, including the AMD Opteron, Athlon 64, and Athlon 64 FX processors. (This supersets MMX, SSE, SSE2, 3DNow!, enhanced 3DNow! and 64-bit instruction set extensions.) k8-sse3 opteron-sse3 athlon64-sse3 Improved versions of AMD K8 cores with SSE3 instruction set support. amdfam10 barcelona CPUs based on AMD Family 10h cores with x86-64 instruction set support. (This supersets MMX, SSE, SSE2, SSE3, SSE4A, 3DNow!, enhanced 3DNow!, ABM and 64-bit instruction set extensions.) bdver1 CPUs based on AMD Family 15h cores with x86-64 instruction set support. (This supersets FMA4, AVX, XOP, LWP, AES, PCLMUL, CX16, MMX, SSE, SSE2, SSE3, SSE4A, SSSE3, SSE4.1, SSE4.2, ABM and 64-bit instruction set extensions.) bdver2 AMD Family 15h core based CPUs with x86-64 instruction set support. (This supersets BMI, TBM, F16C, FMA, FMA4, AVX, XOP, LWP, AES, PCLMUL, CX16, MMX, SSE, SSE2, SSE3, SSE4A, SSSE3, SSE4.1, SSE4.2, ABM and 64-bit instruction set extensions.) bdver3 AMD Family 15h core based CPUs with x86-64 instruction set support. (This supersets BMI, TBM, F16C, FMA, FMA4, FSGSBASE, AVX, XOP, LWP, AES, PCLMUL, CX16, MMX, SSE, SSE2, SSE3, SSE4A, SSSE3, SSE4.1, SSE4.2, ABM and 64-bit instruction set extensions.) bdver4 AMD Family 15h core based CPUs with x86-64 instruction set support. (This supersets BMI, BMI2, TBM, F16C, FMA, FMA4, FSGSBASE, AVX, AVX2, XOP, LWP, AES, PCLMUL, CX16, MOVBE, MMX, SSE, SSE2, SSE3, SSE4A, SSSE3, SSE4.1, SSE4.2, ABM and 64-bit instruction set extensions.) znver1 AMD Family 17h core based CPUs with x86-64 instruction set support. (This supersets BMI, BMI2, F16C, FMA, FSGSBASE, AVX, AVX2, ADCX, RDSEED, MWAITX, SHA, CLZERO, AES, PCLMUL, CX16, MOVBE, MMX, SSE, SSE2, SSE3, SSE4A, SSSE3, SSE4.1, SSE4.2, ABM, XSAVEC, XSAVES, CLFLUSHOPT, POPCNT, and 64-bit instruction set extensions.) znver2 AMD Family 17h core based CPUs with x86-64 instruction set support. (This supersets BMI, BMI2, CLWB, F16C, FMA, FSGSBASE, AVX, AVX2, ADCX, RDSEED, MWAITX, SHA, CLZERO, AES, PCLMUL, CX16, MOVBE, MMX, SSE, SSE2, SSE3, SSE4A, SSSE3, SSE4.1, SSE4.2, ABM, XSAVEC, XSAVES, CLFLUSHOPT, POPCNT, RDPID, WBNOINVD, and 64-bit instruction set extensions.) znver3 AMD Family 19h core based CPUs with x86-64 instruction set support. (This supersets BMI, BMI2, CLWB, F16C, FMA, FSGSBASE, AVX, AVX2, ADCX, RDSEED, MWAITX, SHA, CLZERO, AES, PCLMUL, CX16, MOVBE, MMX, SSE, SSE2, SSE3, SSE4A, SSSE3, SSE4.1, SSE4.2, ABM, XSAVEC, XSAVES, CLFLUSHOPT, POPCNT, RDPID, WBNOINVD, PKU, VPCLMULQDQ, VAES, and 64-bit instruction set extensions.) znver4 AMD Family 19h core based CPUs with x86-64 instruction set support. (This supersets BMI, BMI2, CLWB, F16C, FMA, FSGSBASE, AVX, AVX2, ADCX, RDSEED, MWAITX, SHA, CLZERO, AES, PCLMUL, CX16, MOVBE, MMX, SSE, SSE2, SSE3, SSE4A, SSSE3, SSE4.1, SSE4.2, ABM, XSAVEC, XSAVES, CLFLUSHOPT, POPCNT, RDPID, WBNOINVD, PKU, VPCLMULQDQ, VAES, AVX512F, AVX512DQ, AVX512IFMA, AVX512CD, AVX512BW, AVX512VL, AVX512BF16, AVX512VBMI, AVX512VBMI2, AVX512VNNI, AVX512BITALG, AVX512VPOPCNTDQ, GFNI and 64-bit instruction set extensions.) btver1 CPUs based on AMD Family 14h cores with x86-64 instruction set support. (This supersets MMX, SSE, SSE2, SSE3, SSSE3, SSE4A, CX16, ABM and 64-bit instruction set extensions.) btver2 CPUs based on AMD Family 16h cores with x86-64 instruction set support. This includes MOVBE, F16C, BMI, AVX, PCLMUL, AES, SSE4.2, SSE4.1, CX16, ABM, SSE4A, SSSE3, SSE3, SSE2, SSE, MMX and 64-bit instruction set extensions. winchip-c6 IDT WinChip C6 CPU, dealt in same way as i486 with additional MMX instruction set support. winchip2 IDT WinChip 2 CPU, dealt in same way as i486 with additional MMX and 3DNow! instruction set support. c3 VIA C3 CPU with MMX and 3DNow! instruction set support. (No scheduling is implemented for this chip.) c3-2 VIA C3-2 (Nehemiah/C5XL) CPU with MMX and SSE instruction set support. (No scheduling is implemented for this chip.) c7 VIA C7 (Esther) CPU with MMX, SSE, SSE2 and SSE3 instruction set support. (No scheduling is implemented for this chip.) samuel-2 VIA Eden Samuel 2 CPU with MMX and 3DNow! instruction set support. (No scheduling is implemented for this chip.) nehemiah VIA Eden Nehemiah CPU with MMX and SSE instruction set support. (No scheduling is implemented for this chip.) esther VIA Eden Esther CPU with MMX, SSE, SSE2 and SSE3 instruction set support. (No scheduling is implemented for this chip.) eden-x2 VIA Eden X2 CPU with x86-64, MMX, SSE, SSE2 and SSE3 instruction set support. (No scheduling is implemented for this chip.) eden-x4 VIA Eden X4 CPU with x86-64, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX and AVX2 instruction set support. (No scheduling is implemented for this chip.) nano Generic VIA Nano CPU with x86-64, MMX, SSE, SSE2, SSE3 and SSSE3 instruction set support. (No scheduling is implemented for this chip.) nano-1000 VIA Nano 1xxx CPU with x86-64, MMX, SSE, SSE2, SSE3 and SSSE3 instruction set support. (No scheduling is implemented for this chip.) nano-2000 VIA Nano 2xxx CPU with x86-64, MMX, SSE, SSE2, SSE3 and SSSE3 instruction set support. (No scheduling is implemented for this chip.) nano-3000 VIA Nano 3xxx CPU with x86-64, MMX, SSE, SSE2, SSE3, SSSE3 and SSE4.1 instruction set support. (No scheduling is implemented for this chip.) nano-x2 VIA Nano Dual Core CPU with x86-64, MMX, SSE, SSE2, SSE3, SSSE3 and SSE4.1 instruction set support. (No scheduling is implemented for this chip.) nano-x4 VIA Nano Quad Core CPU with x86-64, MMX, SSE, SSE2, SSE3, SSSE3 and SSE4.1 instruction set support. (No scheduling is implemented for this chip.) lujiazui ZHAOXIN lujiazui CPU with x86-64, MOVBE, MMX, SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, AVX, POPCNT, AES, PCLMUL, RDRND, XSAVE, XSAVEOPT, FSGSBASE, CX16, ABM, BMI, BMI2, F16C, FXSR, RDSEED instruction set support. geode AMD Geode embedded processor with MMX and 3DNow! instruction set support."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Tune to cpu-type everything applicable about the generated code, except for the ABI and the set of available instructions. While picking a specific cpu-type schedules things appropriately for that particular chip, the compiler does not generate any code that cannot run on the default machine type unless you use a -march=cpu-type option. For example, if GCC is configured for i686-pc-linux-gnu then -mtune=pentium4 generates code that is tuned for Pentium 4 but still runs on i686 machines. The choices for cpu-type are the same as for -march. In addition, -mtune supports 2 extra choices for cpu-type: generic Produce code optimized for the most common IA32/AMD64/EM64T processors. If you know the CPU on which your code will run, then you should use the corresponding -mtune or -march option instead of -mtune=generic. But, if you do not know exactly what CPU users of your application will have, then you should use this option. As new processors are deployed in the marketplace, the behavior of this option will change. Therefore, if you upgrade to a newer version of GCC, code generation controlled by this option will change to reflect the processors that are most common at the time that version of GCC is released. There is no -march=generic option because -march indicates the instruction set the compiler can use, and there is no generic instruction set applicable to all processors. In contrast, -mtune indicates the processor (or, in this case, collection of processors) for which the code is optimized. intel Produce code optimized for the most current Intel processors, which are Haswell and Silvermont for this version of GCC. If you know the CPU on which your code will run, then you should use the corresponding -mtune or -march option instead of -mtune=intel. But, if you want your application performs better on both Haswell and Silvermont, then you should use this option. As new Intel processors are deployed in the marketplace, the behavior of this option will change. Therefore, if you upgrade to a newer version of GCC, code generation controlled by this option will change to reflect the most current Intel processors at the time that version of GCC is released. There is no -march=intel option because -march indicates the instruction set the compiler can use, and there is no common instruction set applicable to all processors. In contrast, -mtune indicates the processor (or, in this case, collection of processors) for which the code is optimized."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "A deprecated synonym for -mtune."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate floating-point arithmetic for selected unit unit. The choices for unit are: 387 Use the standard 387 floating-point coprocessor present on the majority of chips and emulated otherwise. Code compiled with this option runs almost everywhere. The temporary results are computed in 80-bit precision instead of the precision specified by the type, resulting in slightly different results compared to most of other chips. See -ffloat-store for more detailed description. This is the default choice for non-Darwin x86-32 targets. sse Use scalar floating-point instructions present in the SSE instruction set. This instruction set is supported by Pentium III and newer chips, and in the AMD line by Athlon-4, Athlon XP and Athlon MP chips. The earlier version of the SSE instruction set supports only single-precision arithmetic, thus the double and extended-precision arithmetic are still done using 387. A later version, present only in Pentium 4 and AMD x86-64 chips, supports double-precision arithmetic too. For the x86-32 compiler, you must use -march=cpu-type, -msse or -msse2 switches to enable SSE extensions and make this option effective. For the x86-64 compiler, these extensions are enabled by default. The resulting code should be considerably faster in the majority of cases and avoid the numerical instability problems of 387 code, but may break some existing code that expects temporaries to be 80 bits. This is the default choice for the x86-64 compiler, Darwin x86-32 targets, and the default choice for x86-32 targets with the SSE2 instruction set when -ffast-math is enabled. sse,387 sse+387 both Attempt to utilize both instruction sets at once. This effectively doubles the amount of available registers, and on chips with separate execution units for 387 and SSE the execution resources too. Use this option with care, as it is still experimental, because the GCC register allocator does not model separate functional units well, resulting in unstable performance."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Output assembly instructions using selected dialect. Also affects which dialect is used for basic \"asm\" and extended \"asm\". Supported choices (in dialect order) are att or intel. The default is att. Darwin does not support intel."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Control whether or not the compiler uses IEEE floating-point comparisons. These correctly handle the case where the result of a comparison is unordered."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output containing 80387 instructions for floating point."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate output containing library calls for floating point. Warning: the requisite libraries are not part of GCC. Normally the facilities of the machine's usual C compiler are used, but this cannot be done directly in cross- compilation. You must make your own arrangements to provide suitable library functions for cross-compilation. On machines where a function returns floating-point results in the 80387 register stack, some floating-point opcodes may be emitted even if -msoft-float is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use the FPU registers for return values of functions. The usual calling convention has functions return values of types \"float\" and \"double\" in an FPU register, even if there is no FPU. The idea is that the operating system should emulate an FPU. The option -mno-fp-ret-in-387 causes such values to be returned in ordinary CPU registers instead."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Some 387 emulators do not support the \"sin\", \"cos\" and \"sqrt\" instructions for the 387. Specify this option to avoid generating those instructions. This option is overridden when -march indicates that the target CPU always has an FPU and so the instruction does not need emulation. These instructions are not generated unless you also use the -funsafe-math-optimizations switch."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Control whether GCC aligns \"double\", \"long double\", and \"long long\" variables on a two- word boundary or a one-word boundary. Aligning \"double\" variables on a two-word boundary produces code that runs somewhat faster on a Pentium at the expense of more memory. On x86-64, -malign-double is enabled by default. Warning: if you use the -malign-double switch, structures containing the above types are aligned differently than the published application binary interface specifications for the x86-32 and are not binary compatible with structures in code compiled without that switch."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These switches control the size of \"long double\" type. The x86-32 application binary interface specifies the size to be 96 bits, so -m96bit-long-double is the default in 32-bit mode. Modern architectures (Pentium and newer) prefer \"long double\" to be aligned to an 8- or 16-byte boundary. In arrays or structures conforming to the ABI, this is not possible. So specifying -m128bit-long-double aligns \"long double\" to a 16-byte boundary by padding the \"long double\" with an additional 32-bit zero. In the x86-64 compiler, -m128bit-long-double is the default choice as its ABI specifies that \"long double\" is aligned on 16-byte boundary. Notice that neither of these options enable any extra precision over the x87 standard of 80 bits for a \"long double\". Warning: if you override the default value for your target ABI, this changes the size of structures and arrays containing \"long double\" variables, as well as modifying the function calling convention for functions taking \"long double\". Hence they are not binary-compatible with code compiled without that switch."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These switches control the size of \"long double\" type. A size of 64 bits makes the \"long double\" type equivalent to the \"double\" type. This is the default for 32-bit Bionic C library. A size of 128 bits makes the \"long double\" type equivalent to the \"float128\" type. This is the default for 64-bit Bionic C library. Warning: if you override the default value for your target ABI, this changes the size of structures and arrays containing \"long double\" variables, as well as modifying the function calling convention for functions taking \"long double\". Hence they are not binary-compatible with code compiled without that switch."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Control how GCC aligns variables. Supported values for type are compat uses increased alignment value compatible uses GCC 4.8 and earlier, abi uses alignment value as specified by the psABI, and cacheline uses increased alignment value to match the cache line size. compat is the default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When -mcmodel=medium is specified, data objects larger than threshold are placed in the large data section. This value must be the same across all objects linked into the binary, and defaults to 65535."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use a different function-calling convention, in which functions that take a fixed number of arguments return with the \"ret num\" instruction, which pops their arguments while returning. This saves one instruction in the caller since there is no need to pop the arguments there. You can specify that an individual function is called with this calling sequence with the function attribute \"stdcall\". You can also override the -mrtd option by using the function attribute \"cdecl\". Warning: this calling convention is incompatible with the one normally used on Unix, so you cannot use it if you need to call libraries compiled with the Unix compiler. Also, you must provide function prototypes for all functions that take variable numbers of arguments (including \"printf\"); otherwise incorrect code is generated for calls to those functions. In addition, seriously incorrect code results if you call a function with too many arguments. (Normally, extra arguments are harmlessly ignored.)"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Control how many registers are used to pass integer arguments. By default, no registers are used to pass arguments, and at most 3 registers can be used. You can control this behavior for a specific function by using the function attribute \"regparm\". Warning: if you use this switch, and num is nonzero, then you must build all modules with the same value, including any libraries. This includes the system libraries and startup modules."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use SSE register passing conventions for float and double arguments and return values. You can control this behavior for a specific function by using the function attribute \"sseregparm\". Warning: if you use this switch then you must build all modules with the same value, including any libraries. This includes the system libraries and startup modules."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Return 8-byte vectors in memory instead of MMX registers. This is the default on VxWorks to match the ABI of the Sun Studio compilers until version 12. Only use this option if you need to remain compatible with existing code produced by those previous compiler versions or older versions of GCC."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set 80387 floating-point precision to 32, 64 or 80 bits. When -mpc32 is specified, the significands of results of floating-point operations are rounded to 24 bits (single precision); -mpc64 rounds the significands of results of floating-point operations to 53 bits (double precision) and -mpc80 rounds the significands of results of floating-point operations to 64 bits (extended double precision), which is the default. When this option is used, floating-point operations in higher precisions are not available to the programmer without setting the FPU control word explicitly. Setting the rounding of floating-point operations to less than the default 80 bits can speed some programs by 2% or more. Note that some mathematical libraries assume that extended-precision (80-bit) floating-point operations are enabled by default; routines in such libraries could suffer significant loss of accuracy, typically through so-called \"catastrophic cancellation\", when this option is used to set the precision to less than extended precision."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The flush-to-zero (FTZ) and denormals-are-zero (DAZ) flags in the MXCSR register are used to control floating-point calculations.SSE and AVX instructions including scalar and vector instructions could benefit from enabling the FTZ and DAZ flags when -mdaz-ftz is specified. Don't set FTZ/DAZ flags when -mno-daz-ftz or -shared is specified, -mdaz-ftz will set FTZ/DAZ flags even with -shared."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Realign the stack at entry. On the x86, the -mstackrealign option generates an alternate prologue and epilogue that realigns the run-time stack if necessary. This supports mixing legacy codes that keep 4-byte stack alignment with modern codes that keep 16-byte stack alignment for SSE compatibility. See also the attribute \"forcealignargpointer\", applicable to individual functions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Attempt to keep the stack boundary aligned to a 2 raised to num byte boundary. If -mpreferred-stack-boundary is not specified, the default is 4 (16 bytes or 128 bits). Warning: When generating code for the x86-64 architecture with SSE extensions disabled, -mpreferred-stack-boundary=3 can be used to keep the stack boundary aligned to 8 byte boundary. Since x86-64 ABI require 16 byte stack alignment, this is ABI incompatible and intended to be used in controlled environment where stack space is important limitation. This option leads to wrong code when functions compiled with 16 byte stack alignment (such as functions from a standard library) are called with misaligned stack. In this case, SSE instructions may lead to misaligned memory access traps. In addition, variable arguments are handled incorrectly for 16 byte aligned objects (including x87 long double and int128), leading to wrong results. You must build all modules with -mpreferred-stack-boundary=3, including any libraries. This includes the system libraries and startup modules."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Assume the incoming stack is aligned to a 2 raised to num byte boundary. If -mincoming-stack-boundary is not specified, the one specified by -mpreferred-stack-boundary is used. On Pentium and Pentium Pro, \"double\" and \"long double\" values should be aligned to an 8-byte boundary (see -malign-double) or suffer significant run time performance penalties. On Pentium III, the Streaming SIMD Extension (SSE) data type \"m128\" may not work properly if it is not 16-byte aligned. To ensure proper alignment of this values on the stack, the stack boundary must be as aligned as that required by any value stored on the stack. Further, every function must be generated such that it keeps the stack aligned. Thus calling a function compiled with a higher preferred stack boundary from a function compiled with a lower preferred stack boundary most likely misaligns the stack. It is recommended that libraries that use callbacks always use the default setting. This extra alignment does consume extra stack space, and generally increases code size. Code that is sensitive to stack space usage, such as embedded systems and operating system kernels, may want to reduce the preferred alignment to -mpreferred-stack-boundary=2."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
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        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
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        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
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        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
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        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
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        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
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        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
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        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
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        {
            "flag": "",
            "long": null,
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        {
            "flag": "",
            "long": null,
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        {
            "flag": "",
            "long": null,
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        {
            "flag": "",
            "long": null,
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        {
            "flag": "",
            "long": null,
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        {
            "flag": "",
            "long": null,
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        {
            "flag": "",
            "long": null,
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        {
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            "long": null,
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        {
            "flag": "",
            "long": null,
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        {
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        {
            "flag": "",
            "long": null,
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        {
            "flag": "",
            "long": null,
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        {
            "flag": "",
            "long": null,
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        {
            "flag": "",
            "long": null,
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        {
            "flag": "",
            "long": null,
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        },
        {
            "flag": "",
            "long": null,
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        },
        {
            "flag": "",
            "long": null,
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        },
        {
            "flag": "",
            "long": null,
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        {
            "flag": "",
            "long": null,
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        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These switches enable the use of instructions in the MMX, SSE, SSE2, SSE3, SSSE3, SSE4, SSE4A, SSE4.1, SSE4.2, AVX, AVX2, AVX512F, AVX512PF, AVX512ER, AVX512CD, AVX512VL, AVX512BW, AVX512DQ, AVX512IFMA, AVX512VBMI, SHA, AES, PCLMUL, CLFLUSHOPT, CLWB, FSGSBASE, PTWRITE, RDRND, F16C, FMA, PCONFIG, WBNOINVD, FMA4, PREFETCHW, RDPID, PREFETCHWT1, RDSEED, SGX, XOP, LWP, 3DNow!, enhanced 3DNow!, POPCNT, ABM, ADX, BMI, BMI2, LZCNT, FXSR, XSAVE, XSAVEOPT, XSAVEC, XSAVES, RTM, HLE, TBM, MWAITX, CLZERO, PKU, AVX512VBMI2, GFNI, VAES, WAITPKG, VPCLMULQDQ, AVX512BITALG, MOVDIRI, MOVDIR64B, AVX512BF16, ENQCMD, AVX512VPOPCNTDQ, AVX5124FMAPS, AVX512VNNI, AVX5124VNNIW, SERIALIZE, UINTR, HRESET, AMXTILE, AMXINT8, AMXBF16, KL, WIDEKL, AVXVNNI, AVX512-FP16, AVXIFMA, AVXVNNIINT8, AVXNECONVERT, CMPCCXADD, AMX-FP16, PREFETCHI, RAOINT, AMX-COMPLEX or CLDEMOTE extended instruction sets. Each has a corresponding -mno- option to disable use of these instructions. These extensions are also available as built-in functions: see x86 Built-in Functions, for details of the functions enabled and disabled by these switches. To generate SSE/SSE2 instructions automatically from floating-point code (as opposed to 387 instructions), see -mfpmath=sse. GCC depresses SSEx instructions when -mavx is used. Instead, it generates new AVX instructions or AVX equivalence for all SSEx instructions when needed. These options enable GCC to use these extended instructions in generated code, even without -mfpmath=sse. Applications that perform run-time CPU detection must compile separate files for each supported architecture, using the appropriate flags. In particular, the file containing the CPU detection code should be compiled without these options."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option instructs GCC to dump the names of the x86 performance tuning features and default settings. The names can be used in -mtune-ctrl=feature-list."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is used to do fine grain control of x86 code generation features. feature- list is a comma separated list of feature names. See also -mdump-tune-features. When specified, the feature is turned on if it is not preceded with ^, otherwise, it is turned off. -mtune-ctrl=feature-list is intended to be used by GCC developers. Using it may lead to code paths not covered by testing and can potentially result in compiler ICEs or runtime errors."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option instructs GCC to turn off all tunable features. See also -mtune-ctrl=feature- list and -mdump-tune-features."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option instructs GCC to emit a \"cld\" instruction in the prologue of functions that use string instructions. String instructions depend on the DF flag to select between autoincrement or autodecrement mode. While the ABI specifies the DF flag to be cleared on function entry, some operating systems violate this specification by not clearing the DF flag in their exception dispatchers. The exception handler can be invoked with the DF flag set, which leads to wrong direction mode when string instructions are used. This option can be enabled by default on 32-bit x86 targets by configuring GCC with the --enable-cld configure option. Generation of \"cld\" instructions can be suppressed with the -mno-cld compiler option in this case."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option instructs GCC to emit a \"vzeroupper\" instruction before a transfer of control flow out of the function to minimize the AVX to SSE transition penalty as well as remove unnecessary \"zeroupper\" intrinsics."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option instructs GCC to use 128-bit AVX instructions instead of 256-bit AVX instructions in the auto-vectorizer."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option instructs GCC to use opt-bit vector width in instructions instead of default on the selected platform."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option instructs GCC to set the maximum number of bits can be moved from memory to memory efficiently to bits. The valid bits are 128, 256 and 512."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option instructs GCC to set the maximum number of bits can be stored to memory efficiently to bits. The valid bits are 128, 256 and 512. none No extra limitations applied to GCC other than defined by the selected platform. 128 Prefer 128-bit vector width for instructions. 256 Prefer 256-bit vector width for instructions. 512 Prefer 512-bit vector width for instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option enables GCC to generate \"CMPXCHG16B\" instructions in 64-bit code to implement compare-and-exchange operations on 16-byte aligned 128-bit objects. This is useful for atomic updates of data structures exceeding one machine word in size. The compiler uses this instruction to implement sync Builtins. However, for atomic Builtins operating on 128-bit integers, a library call is always used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option enables generation of \"SAHF\" instructions in 64-bit code. Early Intel Pentium 4 CPUs with Intel 64 support, prior to the introduction of Pentium 4 G1 step in December 2005, lacked the \"LAHF\" and \"SAHF\" instructions which are supported by AMD64. These are load and store instructions, respectively, for certain status flags. In 64-bit mode, the \"SAHF\" instruction is used to optimize \"fmod\", \"drem\", and \"remainder\" built-in functions; see Other Builtins for details."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option enables use of the \"movbe\" instruction to implement \"builtinbswap32\" and \"builtinbswap64\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The -mshstk option enables shadow stack built-in functions from x86 Control-flow Enforcement Technology (CET)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option enables built-in functions \"builtinia32crc32qi\", \"builtinia32crc32hi\", \"builtinia32crc32si\" and \"builtinia32crc32di\" to generate the \"crc32\" machine instruction."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option enables built-in functions \"builtinia32monitor\", and \"builtinia32mwait\" to generate the \"monitor\" and \"mwait\" machine instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option enables use of \"RCPSS\" and \"RSQRTSS\" instructions (and their vectorized variants \"RCPPS\" and \"RSQRTPS\") with an additional Newton-Raphson step to increase precision instead of \"DIVSS\" and \"SQRTSS\" (and their vectorized variants) for single- precision floating-point arguments. These instructions are generated only when -funsafe-math-optimizations is enabled together with -ffinite-math-only and -fno-trapping-math. Note that while the throughput of the sequence is higher than the throughput of the non-reciprocal instruction, the precision of the sequence can be decreased by up to 2 ulp (i.e. the inverse of 1.0 equals 0.99999994). Note that GCC implements \"1.0f/sqrtf(x)\" in terms of \"RSQRTSS\" (or \"RSQRTPS\") already with -ffast-math (or the above option combination), and doesn't need -mrecip. Also note that GCC emits the above sequence with additional Newton-Raphson step for vectorized single-float division and vectorized sqrtf(x) already with -ffast-math (or the above option combination), and doesn't need -mrecip."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option controls which reciprocal estimate instructions may be used. opt is a comma- separated list of options, which may be preceded by a ! to invert the option: all Enable all estimate instructions. default Enable the default instructions, equivalent to -mrecip. none Disable all estimate instructions, equivalent to -mno-recip. div Enable the approximation for scalar division. vec-div Enable the approximation for vectorized division. sqrt Enable the approximation for scalar square root. vec-sqrt Enable the approximation for vectorized square root. So, for example, -mrecip=all,!sqrt enables all of the reciprocal approximations, except for square root."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specifies the ABI type to use for vectorizing intrinsics using an external library. Supported values for type are svml for the Intel short vector math library and acml for the AMD math core library. To use this option, both -ftree-vectorize and -funsafe-math-optimizations have to be enabled, and an SVML or ACML ABI-compatible library must be specified at link time. GCC currently emits calls to \"vmldExp2\", \"vmldLn2\", \"vmldLog102\", \"vmldPow2\", \"vmldTanh2\", \"vmldTan2\", \"vmldAtan2\", \"vmldAtanh2\", \"vmldCbrt2\", \"vmldSinh2\", \"vmldSin2\", \"vmldAsinh2\", \"vmldAsin2\", \"vmldCosh2\", \"vmldCos2\", \"vmldAcosh2\", \"vmldAcos2\", \"vmlsExp4\", \"vmlsLn4\", \"vmlsLog104\", \"vmlsPow4\", \"vmlsTanh4\", \"vmlsTan4\", \"vmlsAtan4\", \"vmlsAtanh4\", \"vmlsCbrt4\", \"vmlsSinh4\", \"vmlsSin4\", \"vmlsAsinh4\", \"vmlsAsin4\", \"vmlsCosh4\", \"vmlsCos4\", \"vmlsAcosh4\" and \"vmlsAcos4\" for corresponding function type when -mveclibabi=svml is used, and \"vrd2sin\", \"vrd2cos\", \"vrd2exp\", \"vrd2log\", \"vrd2log2\", \"vrd2log10\", \"vrs4sinf\", \"vrs4cosf\", \"vrs4expf\", \"vrs4logf\", \"vrs4log2f\", \"vrs4log10f\" and \"vrs4powf\" for the corresponding function type when -mveclibabi=acml is used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the specified calling convention. Permissible values are sysv for the ABI used on GNU/Linux and other systems, and ms for the Microsoft ABI. The default is to use the Microsoft ABI when targeting Microsoft Windows and the SysV ABI on all other systems. You can control this behavior for specific functions by using the function attributes \"msabi\" and \"sysvabi\"."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force all calls to functions to be indirect. This is useful when using Intel Processor Trace where it generates more precise timing information for function calls."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Insert ENDBR instruction at function entry only via the \"cfcheck\" function attribute. This is useful when used with the option -fcf-protection=branch to control ENDBR insertion at the function entry."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "By default, CET instrumentation is turned off on switch statements that use a jump table and indirect branch track is disabled. Since jump tables are stored in read-only memory, this does not result in a direct loss of hardening. But if the jump table index is attacker-controlled, the indirect jump may not be constrained by CET. This option turns on CET instrumentation to enable indirect branch track for switch statements with jump tables which leads to the jump targets reachable via any indirect jumps."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Due to differences in 64-bit ABIs, any Microsoft ABI function that calls a System V ABI function must consider RSI, RDI and XMM6-15 as clobbered. By default, the code for saving and restoring these registers is emitted inline, resulting in fairly lengthy prologues and epilogues. Using -mcall-ms2sysv-xlogues emits prologues and epilogues that use stubs in the static portion of libgcc to perform these saves and restores, thus reducing function size at the cost of a few extra instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code to access thread-local storage using the gnu or gnu2 conventions. gnu is the conservative default; gnu2 is more efficient, but it may add compile- and run-time requirements that cannot be satisfied on all systems."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Use PUSH operations to store outgoing parameters. This method is shorter and usually equally fast as method using SUB/MOV operations and is enabled by default. In some cases disabling it may improve performance because of improved scheduling and reduced dependencies."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If enabled, the maximum amount of space required for outgoing arguments is computed in the function prologue. This is faster on most modern CPUs because of reduced dependencies, improved scheduling and reduced stack usage when the preferred stack boundary is not equal to 2. The drawback is a notable increase in code size. This switch implies -mno-push-args."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Support thread-safe exception handling on MinGW. Programs that rely on thread-safe exception handling must compile and link all code with the -mthreads option. When compiling, -mthreads defines -DMT; when linking, it links in a special thread helper library -lmingwthrd which cleans up per-thread exception-handling data."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable/disable bit-field layout compatible with the native Microsoft Windows compiler. If \"packed\" is used on a structure, or if bit-fields are used, it may be that the Microsoft ABI lays out the structure differently than the way GCC normally does. Particularly when moving packed data between functions compiled with GCC and the native Microsoft compiler (either via function call or as data in a file), it may be necessary to access either format. This option is enabled by default for Microsoft Windows targets. This behavior can also be controlled locally by use of variable or type attributes. For more information, see x86 Variable Attributes and x86 Type Attributes. The Microsoft structure layout algorithm is fairly simple with the exception of the bit- field packing. The padding and alignment of members of structures and whether a bit- field can straddle a storage-unit boundary are determine by these rules: 1. Structure members are stored sequentially in the order in which they are declared: the first member has the lowest memory address and the last member the highest. 2. Every data object has an alignment requirement. The alignment requirement for all data except structures, unions, and arrays is either the size of the object or the current packing size (specified with either the \"aligned\" attribute or the \"pack\" pragma), whichever is less. For structures, unions, and arrays, the alignment requirement is the largest alignment requirement of its members. Every object is allocated an offset so that: offset % alignmentrequirement == 0 3. Adjacent bit-fields are packed into the same 1-, 2-, or 4-byte allocation unit if the integral types are the same size and if the next bit-field fits into the current allocation unit without crossing the boundary imposed by the common alignment requirements of the bit-fields. MSVC interprets zero-length bit-fields in the following ways: 1. If a zero-length bit-field is inserted between two bit-fields that are normally coalesced, the bit-fields are not coalesced. For example: struct { unsigned long bf1 : 12; unsigned long : 0; unsigned long bf2 : 12; } t1; The size of \"t1\" is 8 bytes with the zero-length bit-field. If the zero-length bit- field were removed, \"t1\"'s size would be 4 bytes. 2. If a zero-length bit-field is inserted after a bit-field, \"foo\", and the alignment of the zero-length bit-field is greater than the member that follows it, \"bar\", \"bar\" is aligned as the type of the zero-length bit-field. For example: struct { char foo : 4; short : 0; char bar; } t2; struct { char foo : 4; short : 0; double bar; } t3; For \"t2\", \"bar\" is placed at offset 2, rather than offset 1. Accordingly, the size of \"t2\" is 4. For \"t3\", the zero-length bit-field does not affect the alignment of \"bar\" or, as a result, the size of the structure. Taking this into account, it is important to note the following: 1. If a zero-length bit-field follows a normal bit-field, the type of the zero-length bit-field may affect the alignment of the structure as whole. For example, \"t2\" has a size of 4 bytes, since the zero-length bit-field follows a normal bit-field, and is of type short. 2. Even if a zero-length bit-field is not followed by a normal bit-field, it may still affect the alignment of the structure: struct { char foo : 6; long : 0; } t4; Here, \"t4\" takes up 4 bytes. 3. Zero-length bit-fields following non-bit-field members are ignored: struct { char foo; long : 0; char bar; } t5; Here, \"t5\" takes up 2 bytes."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not align the destination of inlined string operations. This switch reduces code size and improves performance in case the destination is already aligned, but GCC doesn't know about it."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "By default GCC inlines string operations only when the destination is known to be aligned to least a 4-byte boundary. This enables more inlining and increases code size, but may improve performance of code that depends on fast \"memcpy\" and \"memset\" for short lengths. The option enables inline expansion of \"strlen\" for all pointer alignments."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "For string operations of unknown size, use run-time checks with inline code for small blocks and a library call for large blocks."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Override the internal decision heuristic for the particular algorithm to use for inlining string operations. The allowed values for alg are: repbyte rep4byte rep8byte Expand using i386 \"rep\" prefix of the specified size. byteloop loop unrolledloop Expand into an inline loop. libcall Always use a library call."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Override the internal decision heuristic to decide if \"builtinmemcpy\" should be inlined and what inline algorithm to use when the expected size of the copy operation is known. strategy is a comma-separated list of alg:maxsize:destalign triplets. alg is specified in -mstringop-strategy, maxsize specifies the max byte size with which inline algorithm alg is allowed. For the last triplet, the maxsize must be -1. The maxsize of the triplets in the list must be specified in increasing order. The minimal byte size for alg is 0 for the first triplet and \"maxsize + 1\" of the preceding range."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "The option is similar to -mmemcpy-strategy= except that it is to control \"builtinmemset\" expansion."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Don't keep the frame pointer in a register for leaf functions. This avoids the instructions to save, set up, and restore frame pointers and makes an extra register available in leaf functions. The option -fomit-leaf-frame-pointer removes the frame pointer for leaf functions, which might make debugging harder."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Controls whether TLS variables may be accessed with offsets from the TLS segment register (%gs for 32-bit, %fs for 64-bit), or whether the thread base pointer must be added. Whether or not this is valid depends on the operating system, and whether it maps the segment to cover the entire TLS area. For systems that use the GNU C Library, the default is on."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify that the assembler should encode SSE instructions with VEX prefix. The option -mavx turns this on by default."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If profiling is active (-pg), put the profiling counter call before the prologue. Note: On x86 architectures the attribute \"mshookprologue\" isn't possible at the moment for -mfentry and -pg."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If profiling is active (-pg), generate a mcountloc section that contains pointers to each profiling call. This is useful for automatically patching and out calls."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "If profiling is active (-pg), generate the calls to the profiling functions as NOPs. This is useful when they should be patched in later dynamically. This is likely only useful together with -mrecord-mcount."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Instrument function exit in -pg -mfentry instrumented functions with call to specified function. This only instruments true returns ending with ret, but not sibling calls ending with jump. Valid types are none to not instrument, call to generate a call to return, or nop5 to generate a 5 byte nop."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate a returnloc section pointing to all return instrumentation code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set name of fentry symbol called at function entry for -pg -mfentry functions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Set name of section to record -mrecord-mcount calls (default mcountloc)."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When generating code for the x86-64 architecture with SSE extensions disabled, -mskip-rax-setup can be used to skip setting up RAX register when there are no variable arguments passed in vector registers. Warning: Since RAX register is used to avoid unnecessarily saving vector registers on stack when passing variable arguments, the impacts of this option are callees may waste some stack space, misbehave or jump to a random location. GCC 4.4 or newer don't have those issues, regardless the RAX register value."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "On some processors, like Intel Atom, 8-bit unsigned integer divide is much faster than 32-bit/64-bit integer divide. This option generates a run-time check. If both dividend and divisor are within range of 0 to 255, 8-bit unsigned integer divide is used instead of 32-bit/64-bit integer divide."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Split 32-byte AVX unaligned load and store."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate stack protection code using canary at guard. Supported locations are global for global canary or tls for per-thread canary in the TLS block (the default). This option has effect only when -fstack-protector or -fstack-protector-all is specified. With the latter choice the options -mstack-protector-guard-reg=reg and -mstack-protector-guard-offset=offset furthermore specify which segment register (%fs or %gs) to use as base register for reading the canary, and from what offset from that base register. The default for those is as specified in the relevant ABI."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code that uses only the general-purpose registers. This prevents the compiler from using floating-point, vector, mask and bound registers."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When emitting a compare-and-swap loop for sync Builtins and atomic Builtins lacking a native instruction, optimize for the highly contended case by issuing an atomic load before the \"CMPXCHG\" instruction, and using the \"PAUSE\" instruction to save CPU power when restarting the loop."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Convert indirect call and jump with choice. The default is keep, which keeps indirect call and jump unmodified. thunk converts indirect call and jump to call and return thunk. thunk-inline converts indirect call and jump to inlined call and return thunk. thunk-extern converts indirect call and jump to external call and return thunk provided in a separate object file. You can control this behavior for a specific function by using the function attribute \"indirectbranch\". Note that -mcmodel=large is incompatible with -mindirect-branch=thunk and -mindirect-branch=thunk-extern since the thunk function may not be reachable in the large code model. Note that -mindirect-branch=thunk-extern is compatible with -fcf-protection=branch since the external thunk can be made to enable control-flow check."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Convert function return with choice. The default is keep, which keeps function return unmodified. thunk converts function return to call and return thunk. thunk-inline converts function return to inlined call and return thunk. thunk-extern converts function return to external call and return thunk provided in a separate object file. You can control this behavior for a specific function by using the function attribute \"functionreturn\". Note that -mindirect-return=thunk-extern is compatible with -fcf-protection=branch since the external thunk can be made to enable control-flow check. Note that -mcmodel=large is incompatible with -mfunction-return=thunk and -mfunction-return=thunk-extern since the thunk function may not be reachable in the large code model."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Force indirect call and jump via register."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code to mitigate against straight line speculation (SLS) with choice. The default is none which disables all SLS hardening. return enables SLS hardening for function returns. indirect-jmp enables SLS hardening for indirect jumps. all enables all SLS hardening."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Add CS prefix to call and jmp to indirect thunk with branch target in r8-r15 registers so that the call and jmp instruction length is 6 bytes to allow them to be replaced with lfence; call *%r8-r15 or lfence; jmp *%r8-r15 at run-time. These -m switches are supported in addition to the above on x86-64 processors in 64-bit environments."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for a 16-bit, 32-bit or 64-bit environment. The -m32 option sets \"int\", \"long\", and pointer types to 32 bits, and generates code that runs in 32-bit mode. The -m64 option sets \"int\" to 32 bits and \"long\" and pointer types to 64 bits, and generates code for the x86-64 architecture. For Darwin only the -m64 option also turns off the -fno-pic and -mdynamic-no-pic options. The -mx32 option sets \"int\", \"long\", and pointer types to 32 bits, and generates code for the x86-64 architecture. The -m16 option is the same as -m32, except for that it outputs the \".code16gcc\" assembly directive at the beginning of the assembly output so that the binary can run in 16-bit mode. The -miamcu option generates code which conforms to Intel MCU psABI. It requires the -m32 option to be turned on."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Do not use a so-called \"red zone\" for x86-64 code. The red zone is mandated by the x86-64 ABI; it is a 128-byte area beyond the location of the stack pointer that is not modified by signal or interrupt handlers and therefore can be used for temporary data without adjusting the stack pointer. The flag -mno-red-zone disables this red zone."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the small code model: the program and its symbols must be linked in the lower 2 GB of the address space. Pointers are 64 bits. Programs can be statically or dynamically linked. This is the default code model."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the kernel code model. The kernel runs in the negative 2 GB of the address space. This model has to be used for Linux kernel code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the medium model: the program is linked in the lower 2 GB of the address space. Small symbols are also placed there. Symbols with sizes larger than -mlarge-data-threshold are put into large data or BSS sections and can be located above 2GB. Programs can be statically or dynamically linked."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the large model. This model makes no assumptions about addresses and sizes of sections."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for long address mode. This is only supported for 64-bit and x32 environments. It is the default address mode for 64-bit environments."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for short address mode. This is only supported for 32-bit and x32 environments. It is the default address mode for 32-bit and x32 environments."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Emit GNUPROPERTYX86ISA1NEEDED GNU property for Linux target to indicate the micro- architecture ISA level required to execute the binary."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Without -fpic nor -fPIC, always use the GOT pointer to access external symbols. With -fpic or -fPIC, treat access to protected symbols as local symbols. The default is -mdirect-extern-access. Warning: shared libraries compiled with -mno-direct-extern-access and executable compiled with -mdirect-extern-access may not be binary compatible if protected symbols are used in shared libraries and executable."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Controls conservative small loop unrolling. It is default enabled by O2, and unrolls loop with less than 4 insns by 1 time. Explicit -f[no-]unroll-[all-]loops would disable this flag to avoid any unintended unrolling behavior that user does not want."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "LAM(linear-address masking) allows special bits in the pointer to be used for metadata. The default is none. With u48, pointer bits in positions 62:48 can be used for metadata; With u57, pointer bits in positions 62:57 can be used for metadata. x86 Windows Options These additional options are available for Microsoft Windows targets:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option specifies that a console application is to be generated, by instructing the linker to set the PE header subsystem type required for console applications. This option is available for Cygwin and MinGW targets and is enabled by default on those targets."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is available for Cygwin and MinGW targets. It specifies that a DLL---a dynamic link library---is to be generated, enabling the selection of the required runtime startup object and entry point."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is available for Cygwin and MinGW targets. It specifies that the \"dllimport\" attribute should be ignored."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is available for MinGW targets. It specifies that MinGW-specific thread support is to be used."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is available for MinGW-w64 targets. It causes the \"UNICODE\" preprocessor macro to be predefined, and chooses Unicode-capable runtime startup code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is available for Cygwin and MinGW targets. It specifies that the typical Microsoft Windows predefined macros are to be set in the pre-processor, but does not influence the choice of runtime library/startup code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is available for Cygwin and MinGW targets. It specifies that a GUI application is to be generated by instructing the linker to set the PE header subsystem type appropriately."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is available for MinGW targets. It specifies that the executable flag for the stack used by nested functions isn't set. This is necessary for binaries running in kernel mode of Microsoft Windows, as there the User32 API, which is used to set executable privileges, isn't available."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is available for MinGW and Cygwin targets. It specifies that relocated-data in read-only section is put into the \".data\" section. This is a necessary for older runtimes not supporting modification of \".rdata\" sections for pseudo-relocation."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "This option is available for Cygwin and MinGW targets. It specifies that the GNU extension to the PE file format that permits the correct alignment of COMMON variables should be used when generating code. It is enabled by default if GCC detects that the target assembler found during configuration supports the feature. See also under x86 Options for standard options. Xstormy16 Options These options are defined for Xstormy16:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Choose startup files and linker script suitable for the simulator. Xtensa Options These options are supported for Xtensa targets:"
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable or disable use of \"CONST16\" instructions for loading constant values. The \"CONST16\" instruction is currently not a standard option from Tensilica. When enabled, \"CONST16\" instructions are always used in place of the standard \"L32R\" instructions. The use of \"CONST16\" is enabled by default only if the \"L32R\" instruction is not available."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Enable or disable use of fused multiply/add and multiply/subtract instructions in the floating-point option. This has no effect if the floating-point option is not also enabled. Disabling fused multiply/add and multiply/subtract instructions forces the compiler to use separate instructions for the multiply and add/subtract operations. This may be desirable in some cases where strict IEEE 754-compliant results are required: the fused multiply add/subtract instructions do not round the intermediate result, thereby producing results with more bits of precision than specified by the IEEE standard. Disabling fused multiply add/subtract instructions also ensures that the program output is not sensitive to the compiler's ability to combine multiply and add/subtract operations."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When this option is enabled, GCC inserts \"MEMW\" instructions before \"volatile\" memory references to guarantee sequential consistency. The default is -mserialize-volatile. Use -mno-serialize-volatile to omit the \"MEMW\" instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "For targets, like GNU/Linux, where all user-mode Xtensa code must be position-independent code (PIC), this option disables PIC for compiling kernel code."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These options control the treatment of literal pools. The default is -mno-text-section-literals, which places literals in a separate section in the output file. This allows the literal pool to be placed in a data RAM/ROM, and it also allows the linker to combine literal pools from separate object files to remove redundant literals and improve code size. With -mtext-section-literals, the literals are interspersed in the text section in order to keep them as close as possible to their references. This may be necessary for large assembly files. Literals for each function are placed right before that function."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "These options control the treatment of literal pools. The default is -mno-auto-litpools, which places literals in a separate section in the output file unless -mtext-section-literals is used. With -mauto-litpools the literals are interspersed in the text section by the assembler. Compiler does not produce explicit \".literal\" directives and loads literals into registers with \"MOVI\" instructions instead of \"L32R\" to let the assembler do relaxation and place literals as necessary. This option allows assembler to create several literal pools per function and assemble very big functions, which may not be possible with -mtext-section-literals."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When this option is enabled, GCC instructs the assembler to automatically align instructions to reduce branch penalties at the expense of some code density. The assembler attempts to widen density instructions to align branch targets and the instructions following call instructions. If there are not enough preceding safe density instructions to align a target, no widening is performed. The default is -mtarget-align. These options do not affect the treatment of auto-aligned instructions like \"LOOP\", which the assembler always aligns, either by widening density instructions or by inserting NOP instructions."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": ""
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When this option is enabled, GCC instructs the assembler to translate direct calls to indirect calls unless it can determine that the target of a direct call is in the range allowed by the call instruction. This translation typically occurs for calls to functions in other source files. Specifically, the assembler translates a direct \"CALL\" instruction into an \"L32R\" followed by a \"CALLX\" instruction. The default is -mno-longcalls. This option should be used in programs where the call target can potentially be out of range. This option is implemented in the assembler, not the compiler, so the assembly code generated by GCC still shows direct call instructions---look at the disassembled object code to see the actual instructions. Note that the assembler uses an indirect call for every cross-file call, not just those that really are out of range."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Generate code for the specified ABI. Permissible values are: call0, windowed. Default ABI is chosen by the Xtensa core configuration."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When this option is enabled function parameters are passed in registers \"a2\" through \"a7\", registers \"a12\" through \"a15\" are caller-saved, and register \"a15\" may be used as a frame pointer. When this version of the ABI is enabled the C preprocessor symbol \"XTENSACALL0ABI\" is defined."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "When this option is enabled function parameters are passed in registers \"a10\" through \"a15\", and called function rotates register window by 8 registers on entry so that its arguments are found in registers \"a2\" through \"a7\". Register \"a7\" may be used as a frame pointer. Register window is rotated 8 registers back upon return. When this version of the ABI is enabled the C preprocessor symbol \"XTENSAWINDOWEDABI\" is defined."
        },
        {
            "flag": "",
            "long": null,
            "arg": null,
            "description": "Specify an extra cost of instruction RAM/ROM access for \"L32R\" instructions, in clock cycles. This affects, when optimizing for speed, whether loading a constant from literal pool using \"L32R\" or synthesizing the constant from a small one with a couple of arithmetic instructions. The default value is 0. zSeries Options These are listed under"
        }
    ],
    "examples": [],
    "see_also": [
        {
            "name": "gpl",
            "section": "7",
            "url": "https://www.chedong.com/phpMan.php/man/gpl/7/json"
        },
        {
            "name": "gfdl",
            "section": "7",
            "url": "https://www.chedong.com/phpMan.php/man/gfdl/7/json"
        },
        {
            "name": "fsf-funding",
            "section": "7",
            "url": "https://www.chedong.com/phpMan.php/man/fsf-funding/7/json"
        },
        {
            "name": "cpp",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/cpp/1/json"
        },
        {
            "name": "gcov",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/gcov/1/json"
        },
        {
            "name": "as",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/as/1/json"
        },
        {
            "name": "ld",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/ld/1/json"
        },
        {
            "name": "gdb",
            "section": "1",
            "url": "https://www.chedong.com/phpMan.php/man/gdb/1/json"
        }
    ],
    "tldr": {
        "source": "official",
        "description": "This command is an alias of `gcc`.",
        "examples": [
            {
                "description": "View documentation for the original command",
                "command": "tldr gcc"
            }
        ]
    }
}