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            "text": "# perl5320delta(1) (man)\n\n**Summary:** perl5320delta - what is new for perl v5.32.0\n\n## Section Outline\n\n- **NAME** (2 lines)\n- **DESCRIPTION** (5 lines) — 11 subsections\n  - Core Enhancements (1 lines)\n  - The isa Operator (7 lines)\n  - Unicode 13.0 is supported (2 lines)\n  - Chained comparisons capability (21 lines)\n  - It is now possible to write \"qr/\\p{Name=...}/\", or \"qr!\\p{na (7 lines)\n  - Improvement of \"POSIX::mblen()\", \"mbtowc\", and \"wctomb\" (16 lines)\n  - Alpha assertions are no longer experimental (5 lines)\n  - Script runs are no longer experimental (4 lines)\n  - Feature checks are now faster (4 lines)\n  - Perl is now developed on GitHub (5 lines)\n  - Compiled patterns can now be dumped before optimization (6 lines)\n- **Security** (1 lines) — 19 subsections\n  - [CVE-2020-10543] Buffer overflow caused by a crafted regular (11 lines)\n  - [CVE-2020-10878] Integer overflow via malformed bytecode pro (7 lines)\n  - [CVE-2020-12723] Buffer overflow caused by a crafted regular (6 lines)\n  - Additional Note (5 lines)\n  - Incompatible Changes (1 lines)\n  - Certain pattern matching features are now prohibited in comp (1 lines)\n  - subpatterns (3 lines)\n  - Unused functions \"POSIX::mbstowcs\" and \"POSIX::wcstombs\" are (4 lines)\n  - A bug fix for \"(?[...])\" may have caused some patterns to no (14 lines)\n  - Modifiable variables are no longer permitted in constants (15 lines)\n  - Use of \"vec\" on strings with code points above 0xFF is forbi (3 lines)\n  - Use of code points over 0xFF in string bitwise operators (3 lines)\n  - \"Sys::Hostname::hostname()\" does not accept arguments (2 lines)\n  - Plain \"0\" string now treated as a number for range operator (8 lines)\n  - \"\\K\" now disallowed in look-ahead and look-behind assertions (3 lines)\n  - Performance Enhancements (10 lines)\n  - Modules and Pragmata (1 lines)\n  - Updated Modules and Pragmata (201 lines)\n  - Removed Modules and Pragmata (3 lines)\n- **Documentation** (1 lines) — 1 subsections\n  - Changes to Existing Documentation (154 lines)\n- **Diagnostics** (3 lines) — 6 subsections\n  - New Diagnostics (27 lines)\n  - Changes to Existing Diagnostics (68 lines)\n  - Utility Changes (1 lines)\n  - perlbug (2 lines)\n  - streamzip (5 lines)\n  - Configuration and Compilation (43 lines)\n- **Testing** (22 lines) — 5 subsections\n  - Platform Support (1 lines)\n  - Discontinued Platforms (3 lines)\n  - Platform-Specific Notes (66 lines)\n  - Internal Changes (75 lines)\n  - Selected Bug Fixes (166 lines)\n- **Obituary** (7 lines)\n- **Acknowledgements** (36 lines) — 2 subsections\n  - Reporting Bugs (12 lines)\n  - Give Thanks (7 lines)\n- **SEE ALSO** (11 lines)\n\n## Full Content\n\n### NAME\n\nperl5320delta - what is new for perl v5.32.0\n\n### DESCRIPTION\n\nThis document describes differences between the 5.30.0 release and the 5.32.0 release.\n\nIf you are upgrading from an earlier release such as 5.28.0, first read perl5300delta, which\ndescribes differences between 5.28.0 and 5.30.0.\n\n#### Core Enhancements\n\n#### The isa Operator\n\nA new experimental infix operator called \"isa\" tests whether a given object is an instance of\na given class or a class derived from it:\n\nif( $obj isa Package::Name ) { ... }\n\nFor more detail see \"Class Instance Operator\" in perlop.\n\n#### Unicode 13.0 is supported\n\nSee <https://www.unicode.org/versions/Unicode13.0.0/> for details.\n\n#### Chained comparisons capability\n\nSome comparison operators, as their associativity, chain with some operators of the same\nprecedence (but never with operators of different precedence).\n\nif ( $x < $y <= $z ) {...}\n\nbehaves exactly like:\n\nif ( $x < $y && $y <= $z ) {...}\n\n(assuming that \"$y\" is as simple a scalar as it looks.)\n\nYou can read more about this in perlop under \"Operator Precedence and Associativity\" in\nperlop.\n\nNew Unicode properties \"IdentifierStatus\" and \"IdentifierType\" supported\nUnicode has revised its regular expression requirements:\n<https://www.unicode.org/reports/tr18/tr18-21.html>.  As part of that they are wanting more\nproperties to be exposed, ones that aren't part of the strict UCD (Unicode character\ndatabase). These two are used for examining inputs for security purposes. Details on their\nusage is at <https://www.unicode.org/reports/tr39/>.\n\n#### It is now possible to write \"qr/\\p{Name=...}/\", or \"qr!\\p{na=/(SMILING|GRINNING) FACE/}!\"\n\nThe Unicode Name property is now accessible in regular expression patterns, as an alternative\nto \"\\N{...}\".  A comparison of the two methods is given in \"Comparison of \\N{...} and\n\\p{name=...}\" in perlunicode.\n\nThe second example above shows that wildcard subpatterns are also usable in this property.\nSee \"Wildcards in Property Values\" in perlunicode.\n\n#### Improvement of \"POSIX::mblen()\", \"mbtowc\", and \"wctomb\"\n\nThe \"POSIX::mblen()\", \"mbtowc\", and \"wctomb\" functions now work on shift state locales and\nare thread-safe on C99 and above compilers when executed on a platform that has locale\nthread-safety; the length parameters are now optional.\n\nThese functions are always executed under the current C language locale.  (See perllocale.)\nMost locales are stateless, but a few, notably the very rarely encountered ISO 2022, maintain\na state between calls to these functions. Previously the state was cleared on every call, but\nnow the state is not reset unless the appropriate parameter is \"undef\".\n\nOn threaded perls, the C99 functions mbrlen(3), mbrtowc(3), and wcrtomb(3), when available,\nare substituted for the plain functions.  This makes these functions thread-safe when\nexecuting on a locale thread-safe platform.\n\nThe string length parameters in \"mblen\" and \"mbtowc\" are now optional; useful only if you\nwish to restrict the length parsed in the source string to less than the actual length.\n\n#### Alpha assertions are no longer experimental\n\nSee \"(*pla:pattern)\" in perlre, \"(*plb:pattern)\" in perlre, \"(*nla:pattern)\" in perlre>, and\n\"(*nlb:pattern)\" in perlre.  Use of these no longer generates a warning; existing code that\ndisables the warning category \"experimental::alphaassertions\" will continue to work without\nany changes needed. Enabling the category has no effect.\n\n#### Script runs are no longer experimental\n\nSee \"Script Runs\" in perlre. Use of these no longer generates a warning; existing code that\ndisables the warning category \"experimental::scriptrun\" will continue to work without any\nchanges needed. Enabling the category has no effect.\n\n#### Feature checks are now faster\n\nPreviously feature checks in the parser required a hash lookup when features were set outside\nof a feature bundle, this has been optimized to a bit mask check. [GH #17229\n<https://github.com/Perl/perl5/issues/17229>]\n\n#### Perl is now developed on GitHub\n\nPerl is now developed on GitHub. You can find us at <https://github.com/Perl/perl5>.\n\nNon-security bugs should now be reported via GitHub. Security issues should continue to be\nreported as documented in perlsec.\n\n#### Compiled patterns can now be dumped before optimization\n\nThis is primarily useful for tracking down bugs in the regular expression compiler. This dump\nhappens on \"-DDEBUGGING\" perls, if you specify \"-Drv\" on the command line; or on any perl if\nthe pattern is compiled within the scope of \"use re qw(Debug DUMPPREOPTIMIZE)\" or\n\"use re qw(Debug COMPILE EXTRA)\". (All but the second case display other information as\nwell.)\n\n### Security\n\n#### [CVE-2020-10543] Buffer overflow caused by a crafted regular expression\n\nA signed \"sizet\" integer overflow in the storage space calculations for nested regular\nexpression quantifiers could cause a heap buffer overflow in Perl's regular expression\ncompiler that overwrites memory allocated after the regular expression storage space with\nattacker supplied data.\n\nThe target system needs a sufficient amount of memory to allocate partial expansions of the\nnested quantifiers prior to the overflow occurring.  This requirement is unlikely to be met\non 64-bit systems.\n\nDiscovered by: ManhND of The Tarantula Team, VinCSS (a member of Vingroup).\n\n#### [CVE-2020-10878] Integer overflow via malformed bytecode produced by a crafted regular expression\n\nInteger overflows in the calculation of offsets between instructions for the regular\nexpression engine could cause corruption of the intermediate language state of a compiled\nregular expression.  An attacker could abuse this behaviour to insert instructions into the\ncompiled form of a Perl regular expression.\n\nDiscovered by: Hugo van der Sanden and Slaven Rezic.\n\n#### [CVE-2020-12723] Buffer overflow caused by a crafted regular expression\n\nRecursive calls to \"Sstudychunk()\" by Perl's regular expression compiler to optimize the\nintermediate language representation of a regular expression could cause corruption of the\nintermediate language state of a compiled regular expression.\n\nDiscovered by: Sergey Aleynikov.\n\n#### Additional Note\n\nAn application written in Perl would only be vulnerable to any of the above flaws if it\nevaluates regular expressions supplied by the attacker.  Evaluating regular expressions in\nthis fashion is known to be dangerous since the regular expression engine does not protect\nagainst denial of service attacks in this usage scenario.\n\n#### Incompatible Changes\n\n#### Certain pattern matching features are now prohibited in compiling Unicode property value wildcard\n\n#### subpatterns\n\nThese few features are either inappropriate or interfere with the algorithm used to\naccomplish this task. The complete list is in \"Wildcards in Property Values\" in perlunicode.\n\n#### Unused functions \"POSIX::mbstowcs\" and \"POSIX::wcstombs\" are removed\n\nThese functions could never have worked due to a defective interface specification. There is\nclearly no demand for them, given that no one has ever complained in the many years the\nfunctions were claimed to be available, hence so-called \"support\" for them is now dropped.\n\n#### A bug fix for \"(?[...])\" may have caused some patterns to no longer compile\n\nSee \"Selected Bug Fixes\". The heuristics previously used may have let some constructs compile\n(perhaps not with the programmer's intended effect) that should have been errors. None are\nknown, but it is possible that some erroneous constructs no longer compile.\n\n\"\\p{user-defined}\" properties now always override official Unicode ones\nPreviously, if and only if a user-defined property was declared prior to the compilation of\nthe regular expression pattern that contains it, its definition was used instead of any\nofficial Unicode property with the same name. Now, it always overrides the official property.\nThis change could break existing code that relied (likely unwittingly) on the previous\nbehavior. Without this fix, if Unicode released a new version with a new property that\nhappens to have the same name as the one you had long been using, your program would break\nwhen you upgraded to a perl that used that new Unicode version. See \"User-Defined Character\nProperties\" in perlunicode. [GH #17205 <https://github.com/Perl/perl5/issues/17205>]\n\n#### Modifiable variables are no longer permitted in constants\n\nCode like:\n\nmy $var;\n$sub = sub () { $var };\n\nwhere $var is referenced elsewhere in some sort of modifiable context now produces an\nexception when the sub is defined.\n\nThis error can be avoided by adding a return to the sub definition:\n\n$sub = sub () { return $var };\n\nThis has been deprecated since Perl 5.22.  [GH #17020]\n<https://github.com/Perl/perl5/issues/17020>\n\n#### Use of \"vec\" on strings with code points above 0xFF is forbidden\n\nSuch strings are represented internally in UTF-8, and \"vec\" is a bit-oriented operation that\nwill likely give unexpected results on those strings. This was deprecated in perl 5.28.0.\n\n#### Use of code points over 0xFF in string bitwise operators\n\nSome uses of these were already illegal after a previous deprecation cycle. The remaining\nuses are now prohibited, having been deprecated in perl 5.28.0. See perldeprecation.\n\n#### \"Sys::Hostname::hostname()\" does not accept arguments\n\nThis usage was deprecated in perl 5.28.0 and is now fatal.\n\n#### Plain \"0\" string now treated as a number for range operator\n\nPreviously a range \"0\" .. \"-1\" would produce a range of numeric strings from \"0\" through\n\"99\"; this now produces an empty list, just as \"0 .. -1\" does. This also means that \"0\" ..\n\"9\" now produces a list of integers, where previously it would produce a list of strings.\n\nThis was due to a special case that treated strings starting with \"0\" as strings so ranges\nlike \"00\" .. \"03\" produced \"00\", \"01\", \"02\", \"03\", but didn't specially handle the string\n\"0\".  [GH #16770] <https://github.com/Perl/perl5/issues/16770>\n\n#### \"\\K\" now disallowed in look-ahead and look-behind assertions\n\nThis was disallowed because it causes unexpected behaviour, and no-one could define what the\ndesired behaviour should be.  [GH #14638] <https://github.com/Perl/perl5/issues/14638>\n\n#### Performance Enhancements\n\n•   \"mystrnlen\" has been sped up for systems that don't have their own \"strnlen\"\nimplementation.\n\n•   \"grokbinocthex\" (and so, \"grokbin\", \"grokoct\", and \"grokhex\") have been sped up.\n\n•   \"groknumberflags\" has been sped up.\n\n•   \"sort\" is now noticeably faster in cases such as \"sort {$a <=> $b}\" or \"sort {$b <=>\n$a}\". [GH #17608 <https://github.com/Perl/perl5/pull/17608>]\n\n#### Modules and Pragmata\n\n#### Updated Modules and Pragmata\n\n•   Archive::Tar has been upgraded from version 2.32 to 2.36.\n\n•   autodie has been upgraded from version 2.29 to 2.32.\n\n•   B has been upgraded from version 1.76 to 1.80.\n\n•   B::Deparse has been upgraded from version 1.49 to 1.54.\n\n•   Benchmark has been upgraded from version 1.22 to 1.23.\n\n•   charnames has been upgraded from version 1.45 to 1.48.\n\n•   Class::Struct has been upgraded from version 0.65 to 0.66.\n\n•   Compress::Raw::Bzip2 has been upgraded from version 2.084 to 2.093.\n\n•   Compress::Raw::Zlib has been upgraded from version 2.084 to 2.093.\n\n•   CPAN has been upgraded from version 2.22 to 2.27.\n\n•   DBFile has been upgraded from version 1.843 to 1.853.\n\n•   Devel::PPPort has been upgraded from version 3.52 to 3.57.\n\nThe test files generated on Win32 are now identical to when they are generated on POSIX-\nlike systems.\n\n•   diagnostics has been upgraded from version 1.36 to 1.37.\n\n•   Digest::MD5 has been upgraded from version 2.55 to 2.5501.\n\n•   Dumpvalue has been upgraded from version 1.18 to 1.21.\n\nPreviously, when dumping elements of an array and encountering an undefined value, the\nstring printed would have been \"empty array\". This has been changed to what was\napparently originally intended:  \"empty slot\".\n\n•   DynaLoader has been upgraded from version 1.45 to 1.47.\n\n•   Encode has been upgraded from version 3.01 to 3.06.\n\n•   encoding has been upgraded from version 2.22 to 3.00.\n\n•   English has been upgraded from version 1.10 to 1.11.\n\n•   Exporter has been upgraded from version 5.73 to 5.74.\n\n•   ExtUtils::CBuilder has been upgraded from version 0.280231 to 0.280234.\n\n•   ExtUtils::MakeMaker has been upgraded from version 7.34 to 7.44.\n\n•   feature has been upgraded from version 1.54 to 1.58.\n\nA new \"indirect\" feature has been added, which is enabled by default but allows turning\noff indirect object syntax.\n\n•   File::Find has been upgraded from version 1.36 to 1.37.\n\nOn Win32, the tests no longer require either a file in the drive root directory, or a\nwritable root directory.\n\n•   File::Glob has been upgraded from version 1.32 to 1.33.\n\n•   File::stat has been upgraded from version 1.08 to 1.09.\n\n•   Filter::Simple has been upgraded from version 0.95 to 0.96.\n\n•   Getopt::Long has been upgraded from version 2.5 to 2.51.\n\n•   Hash::Util has been upgraded from version 0.22 to 0.23.\n\nThe Synopsis has been updated as the example code stopped working with newer perls.  [GH\n#17399 <https://github.com/Perl/perl5/issues/17399>]\n\n•   I18N::Langinfo has been upgraded from version 0.18 to 0.19.\n\n•   I18N::LangTags has been upgraded from version 0.43 to 0.44.\n\nDocument the \"IGNOREWIN32LOCALE\" environment variable.\n\n•   IO has been upgraded from version 1.40 to 1.43.\n\nIO::Socket no longer caches a zero protocol value, since this indicates that the\nimplementation will select a protocol. This means that on platforms that don't implement\n\"SOPROTOCOL\" for a given socket type the protocol method may return \"undef\".\n\nThe supplied TO is now always honoured on calls to the \"send()\" method. [GH #16891]\n<https://github.com/Perl/perl5/issues/16891>\n\n•   IO-Compress has been upgraded from version 2.084 to 2.093.\n\n•   IPC::Cmd has been upgraded from version 1.02 to 1.04.\n\n•   IPC::Open3 has been upgraded from version 1.20 to 1.21.\n\n•   JSON::PP has been upgraded from version 4.02 to 4.04.\n\n•   Math::BigInt has been upgraded from version 1.999816 to 1.999818.\n\n•   Math::BigInt::FastCalc has been upgraded from version 0.5008 to 0.5009.\n\n•   Module::CoreList has been upgraded from version 5.20190522 to 5.20200620.\n\n•   Module::Load::Conditional has been upgraded from version 0.68 to 0.70.\n\n•   Module::Metadata has been upgraded from version 1.000036 to 1.000037.\n\n•   mro has been upgraded from version 1.22 to 1.23.\n\n•   Net::Ping has been upgraded from version 2.71 to 2.72.\n\n•   Opcode has been upgraded from version 1.43 to 1.47.\n\n•   open has been upgraded from version 1.11 to 1.12.\n\n•   overload has been upgraded from version 1.30 to 1.31.\n\n•   parent has been upgraded from version 0.237 to 0.238.\n\n•   perlfaq has been upgraded from version 5.20190126 to 5.20200523.\n\n•   PerlIO has been upgraded from version 1.10 to 1.11.\n\n•   PerlIO::encoding has been upgraded from version 0.27 to 0.28.\n\n•   PerlIO::via has been upgraded from version 0.17 to 0.18.\n\n•   Pod::Html has been upgraded from version 1.24 to 1.25.\n\n•   Pod::Simple has been upgraded from version 3.35 to 3.40.\n\n•   podlators has been upgraded from version 4.11 to 4.14.\n\n•   POSIX has been upgraded from version 1.88 to 1.94.\n\n•   re has been upgraded from version 0.37 to 0.40.\n\n•   Safe has been upgraded from version 2.40 to 2.41.\n\n•   Scalar::Util has been upgraded from version 1.50 to 1.55.\n\n•   SelfLoader has been upgraded from version 1.25 to 1.26.\n\n•   Socket has been upgraded from version 2.027 to 2.029.\n\n•   Storable has been upgraded from version 3.15 to 3.21.\n\nUse of \"note()\" from Test::More is now optional in tests. This works around a circular\ndependency with Test::More when installing on very old perls from CPAN.\n\nVstring magic strings over 2GB are now disallowed.\n\nRegular expressions objects weren't properly counted for object id purposes on retrieve.\nThis would corrupt the resulting structure, or cause a runtime error in some cases. [GH\n#17037] <https://github.com/Perl/perl5/issues/17037>\n\n•   Sys::Hostname has been upgraded from version 1.22 to 1.23.\n\n•   Sys::Syslog has been upgraded from version 0.35 to 0.36.\n\n•   Term::ANSIColor has been upgraded from version 4.06 to 5.01.\n\n•   Test::Simple has been upgraded from version 1.302162 to 1.302175.\n\n•   Thread has been upgraded from version 3.04 to 3.05.\n\n•   Thread::Queue has been upgraded from version 3.13 to 3.14.\n\n•   threads has been upgraded from version 2.22 to 2.25.\n\n•   threads::shared has been upgraded from version 1.60 to 1.61.\n\n•   Tie::File has been upgraded from version 1.02 to 1.06.\n\n•   Tie::Hash::NamedCapture has been upgraded from version 0.10 to 0.13.\n\n•   Tie::Scalar has been upgraded from version 1.04 to 1.05.\n\n•   Tie::StdHandle has been upgraded from version 4.5 to 4.6.\n\n•   Time::HiRes has been upgraded from version 1.9760 to 1.9764.\n\nRemoved obsolete code such as support for pre-5.6 perl and classic MacOS. [GH #17096]\n<https://github.com/Perl/perl5/issues/17096>\n\n•   Time::Piece has been upgraded from version 1.33 to 1.3401.\n\n•   Unicode::Normalize has been upgraded from version 1.26 to 1.27.\n\n•   Unicode::UCD has been upgraded from version 0.72 to 0.75.\n\n•   VMS::Stdio has been upgraded from version 2.44 to 2.45.\n\n•   warnings has been upgraded from version 1.44 to 1.47.\n\n•   Win32 has been upgraded from version 0.52 to 0.53.\n\n•   Win32API::File has been upgraded from version 0.1203 to 0.120301.\n\n•   XS::APItest has been upgraded from version 1.00 to 1.09.\n\n#### Removed Modules and Pragmata\n\n•   Pod::Parser has been removed from the core distribution.  It still is available for\ndownload from CPAN. This resolves [#13194 <https://github.com/Perl/perl5/issues/13194>].\n\n### Documentation\n\n#### Changes to Existing Documentation\n\nWe have attempted to update the documentation to reflect the changes listed in this document.\nIf you find any we have missed, open an issue at <https://github.com/Perl/perl5/issues>.\n\nAdditionally, the following selected changes have been made:\n\nperldebguts\n\n•   Simplify a few regnode definitions\n\nUpdate \"BOUND\" and \"NBOUND\" definitions.\n\n•   Add ANYOFHs regnode\n\nThis node is like \"ANYOFHb\", but is used when more than one leading byte is the same in\nall the matched code points.\n\n\"ANYOFHb\" is used to avoid having to convert from UTF-8 to code point for something that\nwon't match. It checks that the first byte in the UTF-8 encoded target is the desired\none, thus ruling out most of the possible code points.\n\nperlapi\n\n•   \"sv2pvbyte\" updated to mention it will croak if the SV cannot be downgraded.\n\n•   \"svsetpvn\" updated to mention that the UTF-8 flag will not be changed by this function,\nand a terminating NUL byte is guaranteed.\n\n•   Documentation for \"PLphase\" has been added.\n\n•   The documentation for \"grokbin\", \"grokoct\", and \"grokhex\" has been updated and\nclarified.\n\nperldiag\n\n•   Add documentation for experimental 'isa' operator\n\n(S experimental::isa) This warning is emitted if you use the (\"isa\") operator. This\noperator is currently experimental and its behaviour may change in future releases of\nPerl.\n\nperlfunc\n\n\"caller\"\nLike \"FILE\" and \"LINE\", the filename and line number returned here may be altered\nby the mechanism described at \"Plain Old Comments (Not!)\" in perlsyn.\n\n\"FILE\"\nIt can be altered by the mechanism described at \"Plain Old Comments (Not!)\" in perlsyn.\n\n\"LINE\"\nIt can be altered by the mechanism described at \"Plain Old Comments (Not!)\" in perlsyn.\n\n\"return\"\nNow mentions that you cannot return from \"do BLOCK\".\n\n\"open\"\nThe \"open()\" section had been renovated significantly.\n\nperlguts\n\n•   No longer suggesting using perl's \"malloc\". Modern system \"malloc\" is assumed to be much\nbetter than perl's implementation now.\n\n•   Documentation about embed.fnc flags has been removed. embed.fnc now has sufficient\ncomments within it. Anyone changing that file will see those comments first, so entries\nhere are now redundant.\n\n•   Updated documentation for \"UTF8f\"\n\n•   Added missing \"=for apidoc\" lines\n\nperlhacktips\n\n•   The differences between Perl strings and C strings are now detailed.\n\nperlintro\n\n•   The documentation for the repetition operator \"x\" have been clarified.  [GH #17335\n<https://github.com/Perl/perl5/issues/17335>]\n\nperlipc\n\n•   The documentation surrounding \"open\" and handle usage has been modernized to prefer 3-arg\nopen and lexical variables instead of barewords.\n\n•   Various updates and fixes including making all examples strict-safe and replacing \"-w\"\nwith \"use warnings\".\n\nperlop\n\n•   'isa' operator is experimental\n\nThis is an experimental feature and is available when enabled by \"use feature 'isa'\". It\nemits a warning in the \"experimental::isa\" category.\n\nperlpod\n\n•   Details of the various stacks within the perl interpreter are now explained here.\n\n•   Advice has been added regarding the usage of \"Z<>\".\n\nperlport\n\n•   Update \"timegm\" example to use the correct year format 1970 instead of 70.  [GH #16431\n<https://github.com/Perl/perl5/issues/16431>]\n\nperlreref\n\n•   Fix some typos.\n\nperlvar\n\n•   Now recommends stringifying $] and comparing it numerically.\n\nperlapi, perlintern\n\n•   Documentation has been added for several functions that were lacking it before.\n\nperlxs\n\n•   Suggest using \"libffi\" for simple library bindings via CPAN modules like FFI::Platypus or\nFFI::Raw.\n\nPOSIX\n\n•   \"setlocale\" warning about threaded builds updated to note it does not apply on Perl\n5.28.X and later.\n\n•   \"Posix::SigSet->new(...)\" updated to state it throws an error if any of the supplied\nsignals cannot be added to the set.\n\nAdditionally, the following selected changes have been made:\n\nUpdating of links\n\n•   Links to the now defunct <https://search.cpan.org> site now point at the equivalent\n<https://metacpan.org> URL. [GH #17393 <https://github.com/Perl/perl5/issues/17393>]\n\n•   The man page for ExtUtils::XSSymSet is now only installed on VMS, which is the only\nplatform the module is installed on. [GH #17424\n<https://github.com/Perl/perl5/issues/17424>]\n\n•   URLs have been changed to \"https://\" and stale links have been updated.\n\nWhere applicable, the URLs in the documentation have been moved from using the \"http://\"\nprotocol to \"https://\". This also affects the location of the bug tracker at\n<https://rt.perl.org>.\n\n•   Some links to OS/2 libraries, Address Sanitizer and other system tools had gone stale.\nThese have been updated with working links.\n\n•   Some links to old email addresses on perl5-porters had gone stale. These have been\nupdated with working links.\n\n### Diagnostics\n\nThe following additions or changes have been made to diagnostic output, including warnings\nand fatal error messages. For the complete list of diagnostic messages, see perldiag.\n\n#### New Diagnostics\n\nNew Errors\n\n•   Expecting interpolated extended charclass in regex; marked by <-- HERE in m/%s/\n\nThis is a replacement for several error messages listed under \"Changes to Existing\nDiagnostics\".\n\n•   \"No digits found for %s literal\"\n\n(F) No hexadecimal digits were found following \"0x\" or no binary digits were found\nfollowing \"0b\".\n\nNew Warnings\n\n•   Code point 0x%X is not Unicode, and not portable\n\nThis is actually not a new message, but it is now output when the warnings category\n\"portable\" is enabled.\n\nWhen raised during regular expression pattern compilation, the warning has extra text\nadded at the end marking where precisely in the pattern it occurred.\n\n•   Non-hex character '%c' terminates \\x early.  Resolved as \"%s\"\n\nThis replaces a warning that was much less specific, and which gave false information.\nThis new warning parallels the similar already-existing one raised for \"\\o{}\".\n\n#### Changes to Existing Diagnostics\n\n•   Character following \"\\c\" must be printable ASCII\n\n...now has extra text added at the end, when raised during regular expression pattern\ncompilation, marking where precisely in the pattern it occurred.\n\n•   Use \"%s\" instead of \"%s\"\n\n...now has extra text added at the end, when raised during regular expression pattern\ncompilation, marking where precisely in the pattern it occurred.\n\n•   Sequence \"\\c{\" invalid\n\n...now has extra text added at the end, when raised during regular expression pattern\ncompilation, marking where precisely in the pattern it occurred.\n\n•   \"\\c%c\" is more clearly written simply as \"%s\"\n\n...now has extra text added at the end, when raised during regular expression pattern\ncompilation, marking where precisely in the pattern it occurred.\n\n•   Non-octal character '%c' terminates \\o early.  Resolved as \"%s\"\n\n...now includes the phrase \"terminates \\o early\", and has extra text added at the end,\nwhen raised during regular expression pattern compilation, marking where precisely in the\npattern it occurred. In some instances the text of the resolution has been clarified.\n\n•   '%s' resolved to '\\o{%s}%d'\n\nAs of Perl 5.32, this message is no longer generated. Instead, \"Non-octal character '%c'\nterminates \\o early.  Resolved as \"%s\"\" in perldiag is used instead.\n\n•   Use of code point 0x%s is not allowed; the permissible max is 0x%X\n\nSome instances of this message previously output the hex digits \"A\", \"B\", \"C\", \"D\", \"E\",\nand \"F\" in lower case. Now they are all consistently upper case.\n\n•   The following three diagnostics have been removed, and replaced by \"Expecting\ninterpolated extended charclass in regex; marked by <-- HERE in m/%s/\" : \"Expecting close\nparen for nested extended charclass in regex; marked by <-- HERE in m/%s/\", \"Expecting\nclose paren for wrapper for nested extended charclass in regex; marked by <-- HERE in\nm/%s/\", and \"Expecting '(?flags:(?[...' in regex; marked by <-- HERE in m/%s/\".\n\n•   The \"Code point 0x%X is not Unicode, and not portable\" warning removed the line \"Code\npoints above 0xFFFFFFFF require larger than a 32 bit word.\"  as code points that large\nare no longer legal on 32-bit platforms.\n\n•   Can't use global %s in %s\n\nThis error message has been slightly reformatted from the original \"Can't use global %s\nin \"%s\"\", and in particular misleading error messages like \"Can't use global $ in \"my\"\"\nare now rendered as \"Can't use global $ in subroutine signature\".\n\n•   Constants from lexical variables potentially modified elsewhere are no longer permitted\n\nThis error message replaces the former \"Constants from lexical variables potentially\nmodified elsewhere are deprecated. This will not be allowed in Perl 5.32\" to reflect the\nfact that this previously deprecated usage has now been transformed into an exception.\nThe message's classification has also been updated from D (deprecated) to F (fatal).\n\nSee also \"Incompatible Changes\".\n\n•   \"\\N{} here is restricted to one character\" is now emitted in the same circumstances where\npreviously \"\\N{} in inverted character class or as a range end-point is restricted to one\ncharacter\" was.\n\nThis is due to new circumstances having been added in Perl 5.30 that weren't covered by\nthe earlier wording.\n\n#### Utility Changes\n\n#### perlbug\n\n•   The bug tracker homepage URL now points to GitHub.\n\n#### streamzip\n\n•   This is a new utility, included as part of an IO::Compress::Base upgrade.\n\nstreamzip creates a zip file from stdin. The program will read data from stdin, compress\nit into a zip container and, by default, write a streamed zip file to stdout.\n\n#### Configuration and Compilation\n\nConfigure\n•   For clang++, add \"#include <stdlib.h>\" to Configure's probes for \"futimes\", \"strtoll\",\n\"strtoul\", \"strtoull\", \"strtouq\", otherwise the probes would fail to compile.\n\n•   Use a compile and run test for \"lchown\" to satisfy clang++ which should more reliably\ndetect it.\n\n•   For C++ compilers, add \"#include <stdio.h>\" to Configure's probes for \"getpgrp\" and\n\"setpgrp\" as they use printf and C++ compilers may fail compilation instead of just\nwarning.\n\n•   Check if the compiler can handle inline attribute.\n\n•   Check for character data alignment.\n\n•   Configure now correctly handles gcc-10. Previously it was interpreting it as gcc-1 and\nturned on \"-fpcc-struct-return\".\n\n•   Perl now no longer probes for \"du32align\", defaulting to \"define\" on all platforms. This\ncheck was error-prone when it was done, which was on 32-bit platforms only.  [GH #16680]\n<https://github.com/Perl/perl5/issues/16680>\n\n•   Documentation and hints for building perl on Z/OS (native EBCDIC) have been updated. This\nis still a work in progress.\n\n•   A new probe for \"mallocusablesize\" has been added.\n\n•   Improvements in Configure to detection in C++ and clang++. Work ongoing by Andy\nDougherty. [GH #17033] <https://github.com/Perl/perl5/issues/17033>\n\n•   autodoc.pl\n\nThis tool that regenerates perlintern and perlapi has been overhauled significantly,\nrestoring consistency in flags used in embed.fnc and Devel::PPPort and allowing removal\nof many redundant \"=for apidoc\" entries in code.\n\n•   The \"ECHO\" macro is now defined. This is used in a \"dtrace\" rule that was originally\nchanged for FreeBSD, and the FreeBSD make apparently predefines it.  The Solaris make\ndoes not predefine \"ECHO\" which broke this rule on Solaris.  [GH #17057]\n<https://github.com/Perl/perl5/issues/17057>\n\n•   Bison versions 3.1 through 3.4 are now supported.\n\n### Testing\n\nTests were added and changed to reflect the other additions and changes in this release.\nFurthermore, these significant changes were made:\n\n•   t/run/switches.t no longer uses (and re-uses) the tmpinplace/ directory under t/. This\nmay prevent spurious failures. [GH #17424 <https://github.com/Perl/perl5/issues/17424>]\n\n•   Various bugs in \"POSIX::mbtowc\" were fixed. Potential races with other threads are now\navoided, and previously the returned wide character could well be garbage.\n\n•   Various bugs in \"POSIX::wctomb\" were fixed. Potential races with other threads are now\navoided, and previously it would segfault if the string parameter was shared or hadn't\nbeen pre-allocated with a string of sufficient length to hold the result.\n\n•   Certain test output of scalars containing control characters and Unicode has been fixed\non EBCDIC.\n\n•   t/charsettools.pl: Avoid some work on ASCII platforms.\n\n•   t/re/regexp.t: Speed up many regex tests on ASCII platform\n\n•   t/re/pat.t: Skip tests that don't work on EBCDIC.\n\n#### Platform Support\n\n#### Discontinued Platforms\n\nWindows CE\nSupport for building perl on Windows CE has now been removed.\n\n#### Platform-Specific Notes\n\nLinux\n\"cc\" will be used to populate \"plibpth\" if \"cc\" is \"clang\".  [GH #17043]\n<https://github.com/Perl/perl5/issues/17043>\n\nNetBSD 8.0\nFix compilation of Perl on NetBSD 8.0 with g++.  [GH #17381\n<https://github.com/Perl/perl5/issues/17381>]\n\nWindows\n•   The configuration for \"ccflags\" and \"optimize\" are now separate, as with POSIX\nplatforms. [GH #17156 <https://github.com/Perl/perl5/issues/17156>]\n\n•   Support for building perl with Visual C++ 6.0 has now been removed.\n\n•   The locale tests could crash on Win32 due to a Windows bug, and separately due to the\nCRT throwing an exception if the locale name wasn't validly encoded in the current\ncode page.\n\nFor the second we now decode the locale name ourselves, and always decode it as\nUTF-8. [GH #16922] <https://github.com/Perl/perl5/issues/16922>\n\n•   t/op/magic.t could fail if environment variables starting with \"FOO\" already existed.\n\n•   MYMALLOC (PERLMALLOC) build has been fixed.\n\nSolaris\n•   \"Configure\" will now find recent versions of the Oracle Developer Studio compiler,\nwhich are found under \"/opt/developerstudio*\".\n\n•   \"Configure\" now uses the detected types for \"gethostby*\" functions, allowing Perl to\nonce again compile on certain configurations of Solaris.\n\nVMS\n•   With the release of the patch kit C99 V2.0, VSI has provided support for a number of\npreviously-missing C99 features. On systems with that patch kit installed, Perl's\nconfiguration process will now detect the presence of the header \"stdint.h\" and the\nfollowing functions: \"fpclassify\", \"isblank\", \"isless\", \"llrint\", \"llrintl\",\n\"llround\", \"llroundl\", \"nearbyint\", \"round\", \"scalbn\", and \"scalbnl\".\n\n•   \"-Duse64bitint\" is now the default on VMS.\n\nz/OS\nPerl 5.32 has been tested on z/OS 2.4, with the following caveats:\n\n•   Only static builds (the default) build reliably\n\n•   When using locales, z/OS does not handle the \"LCMESSAGES\" category properly, so when\ncompiling perl, you should add the following to your Configure options\n\n./Configure <other options> -Accflags=-DNOLOCALEMESSAGES\n\n•   z/OS does not support locales with threads, so when compiling a threaded perl, you\nshould add the following to your Configure options\n\n./Configure <other Configure options> -Accflags=-DNOLOCALE\n\n•   Some CPAN modules that are shipped with perl fail at least one of their self-tests.\nThese are: Archive::Tar, Config::Perl::V, CPAN::Meta, CPAN::Meta::YAML, Digest::MD5,\nDigest::SHA, Encode, ExtUtils::MakeMaker, ExtUtils::Manifest, HTTP::Tiny,\nIO::Compress, IPC::Cmd, JSON::PP, libnet, MIME::Base64, Module::Metadata,\nPerlIO::via-QuotedPrint, Pod::Checker, podlators, Pod::Simple, Socket, and\nTest::Harness.\n\nThe causes of the failures range from the self-test itself is flawed, and the module\nactually works fine, up to the module doesn't work at all on EBCDIC platforms.\n\n#### Internal Changes\n\n•   \"savepvn\"'s len parameter is now a \"Sizet\" instead of an \"I32\" since we can handle\nlonger strings than 31 bits.\n\n•   The lexer (\"Perlyylex()\" in toke.c) was previously a single 4100-line function, relying\nheavily on \"goto\" and a lot of widely-scoped local variables to do its work. It has now\nbeen pulled apart into a few dozen smaller static functions; the largest remaining chunk\n(\"yylwordorkeyword()\") is a little over 900 lines, and consists of a single \"switch\"\nstatement, all of whose \"case\" groups are independent. This should be much easier to\nunderstand and maintain.\n\n•   The OS-level signal handlers and type (Sighandlert) used by the perl core were declared\nas having three parameters, but the OS was always told to call them with one argument.\nThis has been fixed by declaring them to have one parameter. See the merge commit\n\"v5.31.5-346-g116e19abbf\" for full details.\n\n•   The code that handles \"tr///\" has been extensively revised, fixing various bugs,\nespecially when the source and/or replacement strings contain characters whose code\npoints are above 255. Some of the bugs were undocumented, one being that under some\ncircumstances (but not all) with \"/s\", the squeezing was done based on the source, rather\nthan the replacement. A documented bug that got fixed was [GH #14777]\n<https://github.com/Perl/perl5/issues/14777>.\n\n•   A new macro for XS writers dealing with UTF-8-encoded Unicode strings has been created\n\"\"UTF8CHKSKIP\"\" in perlapi that is safer in the face of malformed UTF-8 input than\n\"\"UTF8SKIP\"\" in perlapi (but not as safe as \"\"UTF8SAFESKIP\"\" in perlapi). It won't\nread past a NUL character.  It has been backported in Devel::PPPort 3.55 and later.\n\n•   Added the \"PLcurstackinfo->sicxsubix\" field. This records the stack index of the most\nrecently pushed sub/format/eval context. It is set and restored automatically by\n\"cxpushsub()\", \"cxpopsub()\" etc., but would need to be manually managed if you do any\nunusual manipulation of the context stack.\n\n•   Various macros dealing with character type classification and changing case where the\ninput is encoded in UTF-8 now require an extra parameter to prevent potential reads\nbeyond the end of the buffer. Use of these has generated a deprecation warning since Perl\n5.26. Details are in \"In XS code, use of various macros dealing with UTF-8.\" in\nperldeprecation\n\n•   A new parser function parsesubsignature() allows a keyword plugin to parse a subroutine\nsignature while \"use feature 'signatures'\" is in effect. This allows custom keywords to\nimplement semantics similar to regular \"sub\" declarations that include signatures.  [GH\n#16261] <https://github.com/Perl/perl5/issues/16261>\n\n•   Since on some platforms we need to hold a mutex when temporarily switching locales, new\nmacros (\"STORELCNUMERICSETTONEEDEDIN\", \"WITHLCNUMERICSETTONEEDED\" and\n\"WITHLCNUMERICSETTONEEDEDIN\") have been added to make it easier to do this safely\nand efficiently as part of [GH #17034] <https://github.com/Perl/perl5/issues/17034>.\n\n•   The memory bookkeeping overhead for allocating an OP structure has been reduced by 8\nbytes per OP on 64-bit systems.\n\n•   evalpv() no longer stringifies the exception when \"[GH\n#17035]|https://github.com/Perl/perl5/issues/17035\"]\n\n•   The PERLDESTRUCTLEVEL environment variable was formerly only honoured on perl binaries\nbuilt with DEBUGGING support. It is now checked on all perl builds.  Its normal use is to\nforce perl to individually free every block of memory which it has allocated before\nexiting, which is useful when using automated leak detection tools such as valgrind.\n\n•   The API evalsv() now accepts a \"GRETHROW\" flag. If this flag is set and an exception is\nthrown while compiling or executing the supplied code, it will be rethrown, and evalsv()\nwill not return.  [GH #17036] <https://github.com/Perl/perl5/issues/17036>\n\n•   As part of the fix for [GH #1537] <https://github.com/Perl/perl5/issues/1537>\nperlparse() now returns non-zero if exit(0) is called in a \"BEGIN\", \"UNITCHECK\" or\n\"CHECK\" block.\n\n•   Most functions which recursively walked an op tree during compilation have been made non-\nrecursive. This avoids SEGVs from stack overflow when the op tree is deeply nested, such\nas \"$n == 1 ? \"one\" : $n == 2 ? \"two\" : ....\" (especially in code which is auto-\ngenerated).\n\nThis is particularly noticeable where the code is compiled within a separate thread, as\nthreads tend to have small stacks by default.\n\n#### Selected Bug Fixes\n\n•   Previously \"require\" in perlfunc would only treat the special built-in SV &PLsvundef as\na value in %INC as if a previous \"require\" has failed, treating other undefined SVs as if\nthe previous \"require\" has succeeded. This could cause unexpected success from \"require\"\ne.g., on \"local %INC = %INC;\". This has been fixed. [GH #17428\n<https://github.com/Perl/perl5/issues/17428>]\n\n•   \"(?{...})\" eval groups in regular expressions no longer unintentionally trigger \"EVAL\nwithout pos change exceeded limit in regex\" [GH #17490\n<https://github.com/Perl/perl5/issues/17490>].\n\n•   \"(?[...])\" extended bracketed character classes do not wrongly raise an error on some\ncases where a previously-compiled such class is interpolated into another. The heuristics\npreviously used have been replaced by a reliable method, and hence the diagnostics\ngenerated have changed. See \"Diagnostics\".\n\n•   The debug display (say by specifying \"-Dr\" or \"use re\" (with appropriate options) of\ncompiled Unicode property wildcard subpatterns no longer has extraneous output.\n\n•   Fix an assertion failure in the regular expression engine.  [GH #17372\n<https://github.com/Perl/perl5/issues/17372>]\n\n•   Fix coredump in pphot.c after \"B::UNOPAUX::auxlist()\".  [GH #17301\n<https://github.com/Perl/perl5/issues/17301>]\n\n•   Loading IO is now threadsafe.  [GH #14816 <https://github.com/Perl/perl5/issues/14816>]\n\n•   \"\\p{user-defined}\" overrides official Unicode [GH #17025\n<https://github.com/Perl/perl5/issues/17025>]\n\nPrior to this patch, the override was only sometimes in effect.\n\n•   Properly handle filled \"/il\" regnodes and multi-char folds\n\n•   Compilation error during make minitest [GH #17293\n<https://github.com/Perl/perl5/issues/17293>]\n\n•   Move the implementation of \"%-\", \"%+\" into core.\n\n•   Read beyond buffer in \"grokinfnan\" [GH #17370\n<https://github.com/Perl/perl5/issues/17370>]\n\n•   Workaround glibc bug with \"LCMESSAGES\" [GH #17081\n<https://github.com/Perl/perl5/issues/17081>]\n\n•   \"printf()\" or \"sprintf()\" with the %n format could cause a panic on debugging builds, or\nreport an incorrectly cached length value when producing \"SVfUTF8\" flagged strings. [GH\n#17221 <https://github.com/Perl/perl5/issues/17221>]\n\n•   The tokenizer has been extensively refactored.  [GH #17241\n<https://github.com/Perl/perl5/issues/17241>] [GH #17189\n<https://github.com/Perl/perl5/issues/17189>]\n\n•   \"use strict \"subs\"\" is now enforced for bareword constants optimized into a \"multiconcat\"\noperator. [GH #17254 <https://github.com/Perl/perl5/issues/17254>]\n\n•   A memory leak in regular expression patterns has been fixed. [GH #17218\n<https://github.com/Perl/perl5/issues/17218>]\n\n•   Perl no longer treats strings starting with \"0x\" or \"0b\" as hex or binary numbers\nrespectively when converting a string to a number.  This reverts a change in behaviour\ninadvertently introduced in perl 5.30.0 intended to improve precision when converting a\nstring to a floating point number. [GH #17062]\n<https://github.com/Perl/perl5/issues/17062>\n\n•   Matching a non-\"SVfUTF8\" string against a regular expression containing unicode literals\ncould leak a SV on each match attempt.  [GH #17140]\n<https://github.com/Perl/perl5/issues/17140>\n\n•   Overloads for octal and binary floating point literals were always passed a string with a\n\"0x\" prefix instead of the appropriate 0 or \"[GH\n#14791]|https://github.com/Perl/perl5/issues/14791\"]\n\n•   \"$@ = 100; die;\" now correctly propagates the 100 as an exception instead of ignoring it.\n[GH #17098] <https://github.com/Perl/perl5/issues/17098>\n\n•   \"[GH #17108]|https://github.com/Perl/perl5/issues/17108\"]\n\n•   Exceptions thrown while $@ is read-only could result in infinite recursion as perl tried\nto update $@, which throws another exception, resulting in a stack overflow. Perl now\nreplaces $@ with a copy if it's not a simple writable SV. [GH #17083]\n<https://github.com/Perl/perl5/issues/17083>\n\n•   Setting $) now properly sets supplementary group ids if you have the necessary\nprivileges. [GH #17031] <https://github.com/Perl/perl5/issues/17031>\n\n•   close() on a pipe now preemptively clears the PerlIO object from the IO SV. This prevents\na second attempt to close the already closed PerlIO object if a signal handler calls\ndie() or exit() while close() is waiting for the child process to complete. [GH #13929]\n<https://github.com/Perl/perl5/issues/13929>\n\n•   \"sprintf(\"%.*a\", -10000, $x)\" would cause a buffer overflow due to mishandling of the\nnegative precision value. [GH #16942] <https://github.com/Perl/perl5/issues/16942>\n\n•   scalar() on a reference could cause an erroneous assertion failure during compilation.\n[GH #16969] <https://github.com/Perl/perl5/issues/16969>\n\n•   \"%{^CAPTUREALL}\" is now an alias to \"%-\" as documented, rather than incorrectly an alias\nfor \"[GH #16105]|https://github.com/Perl/perl5/issues/16105\"]\n\n•   \"%{^CAPTURE}\" didn't work if \"@{^CAPTURE}\" was mentioned first.  Similarly for\n\"%{^CAPTUREALL}\" and \"@{^CAPTUREALL}\", though \"[GH\n#17045]|https://github.com/Perl/perl5/issues/17045\"]\n\n•   Extraordinarily large (over 2GB) floating point format widths could cause an integer\noverflow in the underlying call to snprintf(), resulting in an assertion. Formatted\nfloating point widths are now limited to the range of int, the return value of\nsnprintf().  [#16881 <https://github.com/Perl/perl5/issues/16881>]\n\n•   Parsing the following constructs within a sub-parse (such as with \"${code here}\" or\n\"s/.../code here/e\") has changed to match how they're parsed normally:\n\n•   \"print $fh ...\" no longer produces a syntax error.\n\n•   Code like \"s/.../ ${time} /e\" now properly produces an \"Ambiguous use of ${time}\nresolved to $time at ...\" warning when warnings are enabled.\n\n•   \"@x {\"a\"}\" (with the space) in a sub-parse now properly produces a \"better written\nas\" warning when warnings are enabled.\n\n•   Attributes can now be used in a sub-parse.  [GH #16847]\n<https://github.com/Perl/perl5/issues/16847>\n\n•   Incomplete hex and binary literals like \"0x\" and \"0b\" are now treated as if the \"x\" or\n\"b\" is part of the next token.  [#17010 <https://github.com/Perl/perl5/issues/17010>]\n\n•   A spurious \")\" in a subparse, such as in \"s/.../code here/e\" or \"...${code here}\", no\nlonger confuses the parser.\n\nPreviously a subparse was bracketed with generated \"(\" and \")\" tokens, so a spurious \")\"\nwould close the construct without doing the normal subparse clean up, confusing the\nparser and possible causing an assertion failure.\n\nSuch constructs are now surrounded by artificial tokens that can't be included in the\nsource. [GH #15814] <https://github.com/Perl/perl5/issues/15814>\n\n•   Reference assignment of a sub, such as \"\\&foo = \\&bar;\", silently did nothing in the \"[GH\n#16987]|https://github.com/Perl/perl5/issues/16987\"]\n\n•   svgets() now recovers better if the target SV is modified by a signal handler. [GH\n#16960] <https://github.com/Perl/perl5/issues/16960>\n\n•   \"readline @foo\" now evaluates @foo in scalar context. Previously it would be evaluated in\nlist context, and since readline() pops only one argument from the stack, the stack could\nunderflow, or be left with unexpected values on the stack. [GH #16929]\n<https://github.com/Perl/perl5/issues/16929>\n\n•   Parsing incomplete hex or binary literals was changed in 5.31.1 to treat such a literal\nas just the 0, leaving the following \"x\" or \"b\" to be parsed as part of the next token.\nThis could lead to some silent changes in behaviour, so now incomplete hex or binary\nliterals produce a fatal error.  [GH #17010] <https://github.com/Perl/perl5/issues/17010>\n\n•   evalpv()'s croakonerror flag will now throw even if the exception is a false\noverloaded value.  [GH #17036] <https://github.com/Perl/perl5/issues/17036>\n\n•   \"INIT\" blocks and the program itself are no longer run if exit(0) is called within a\n\"BEGIN\", \"UNITCHECK\" or \"CHECK\" block.  [GH #1537]\n<https://github.com/Perl/perl5/issues/1537>\n\n•   \"open my $fh, \">>+\", undef\" now opens the temporary file in append mode: writes will seek\nto the end of file before writing.  [GH #17058]\n<https://github.com/Perl/perl5/issues/17058>\n\n•   Fixed a SEGV when searching for the source of an uninitialized value warning on an op\nwhose subtree includes an OPMULTIDEREF.  [GH #17088]\n<https://github.com/Perl/perl5/issues/17088>\n\n### Obituary\n\nJeff Goff (JGOFF or DrForr), an integral part of the Perl and Raku communities and a dear\nfriend to all of us, has passed away on March 13th, 2020. DrForr was a prominent member of\nthe communities, attending and speaking at countless events, contributing to numerous\nprojects, and assisting and helping in any way he could.\n\nHis passing leaves a hole in our hearts and in our communities and he will be sorely missed.\n\n### Acknowledgements\n\nPerl 5.32.0 represents approximately 13 months of development since Perl 5.30.0 and contains\napproximately 220,000 lines of changes across 1,800 files from 89 authors.\n\nExcluding auto-generated files, documentation and release tools, there were approximately\n140,000 lines of changes to 880 .pm, .t, .c and .h files.\n\nPerl continues to flourish into its fourth decade thanks to a vibrant community of users and\ndevelopers. The following people are known to have contributed the improvements that became\nPerl 5.32.0:\n\nAaron Crane, Alberto Simões, Alexandr Savca, Andreas König, Andrew Fresh, Andy Dougherty, Ask\nBjørn Hansen, Atsushi Sugawara, Bernhard M. Wiedemann, brian d foy, Bryan Stenson, Chad\nGranum, Chase Whitener, Chris 'BinGOs' Williams, Craig A. Berry, Dagfinn Ilmari Mannsåker,\nDan Book, Daniel Dragan, Dan Kogai, Dave Cross, Dave Rolsky, David Cantrell, David Mitchell,\nDominic Hargreaves, E. Choroba, Felipe Gasper, Florian Weimer, Graham Knop, Håkon Hægland,\nHauke D, H.Merijn Brand, Hugo van der Sanden, Ichinose Shogo, James E Keenan, Jason McIntosh,\nJerome Duval, Johan Vromans, John Lightsey, John Paul Adrian Glaubitz, Kang-min Liu, Karen\nEtheridge, Karl Williamson, Leon Timmermans, Manuel Mausz, Marc Green, Matthew Horsfall, Matt\nTurner, Max Maischein, Michael Haardt, Nicholas Clark, Nicolas R., Niko Tyni, Pali, Paul\nEvans, Paul Johnson, Paul Marquess, Peter Eisentraut, Peter John Acklam, Peter Oliver, Petr\nPísař, Renee Baecker, Ricardo Signes, Richard Leach, Russ Allbery, Samuel Smith, Santtu\nOjanperä, Sawyer X, Sergey Aleynikov, Sergiy Borodych, Shirakata Kentaro, Shlomi Fish,\nSisyphus, Slaven Rezic, Smylers, Stefan Seifert, Steve Hay, Steve Peters, Svyatoslav,\nThibault Duponchelle, Todd Rinaldo, Tomasz Konojacki, Tom Hukins, Tony Cook, Unicode\nConsortium, VanL, Vickenty Fesunov, Vitali Peil, Yves Orton, Zefram.\n\nThe list above is almost certainly incomplete as it is automatically generated from version\ncontrol history. In particular, it does not include the names of the (very much appreciated)\ncontributors who reported issues to the Perl bug tracker.\n\nMany of the changes included in this version originated in the CPAN modules included in\nPerl's core. We're grateful to the entire CPAN community for helping Perl to flourish.\n\nFor a more complete list of all of Perl's historical contributors, please see the AUTHORS\nfile in the Perl source distribution.\n\n#### Reporting Bugs\n\nIf you find what you think is a bug, you might check the perl bug database at\n<https://github.com/Perl/perl5/issues>. There may also be information at\n<http://www.perl.org/>, the Perl Home Page.\n\nIf you believe you have an unreported bug, please open an issue at\n<https://github.com/Perl/perl5/issues>. Be sure to trim your bug down to a tiny but\nsufficient test case.\n\nIf the bug you are reporting has security implications which make it inappropriate to send to\na public issue tracker, then see \"SECURITY VULNERABILITY CONTACT INFORMATION\" in perlsec for\ndetails of how to report the issue.\n\n#### Give Thanks\n\nIf you wish to thank the Perl 5 Porters for the work we had done in Perl 5, you can do so by\nrunning the \"perlthanks\" program:\n\nperlthanks\n\nThis will send an email to the Perl 5 Porters list with your show of thanks.\n\n### SEE ALSO\n\nThe Changes file for an explanation of how to view exhaustive details on what changed.\n\nThe INSTALL file for how to build Perl.\n\nThe README file for general stuff.\n\nThe Artistic and Copying files for copyright information.\n\n\n\nperl v5.34.0                                 2025-07-25                             PERL5320DELTA(1)\n\n"
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                "name": "DESCRIPTION",
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                "subsections": [
                    {
                        "name": "Core Enhancements",
                        "lines": 1
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                    {
                        "name": "The isa Operator",
                        "lines": 7
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                    {
                        "name": "Unicode 13.0 is supported",
                        "lines": 2
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                        "name": "Chained comparisons capability",
                        "lines": 21
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                    {
                        "name": "It is now possible to write \"qr/\\p{Name=...}/\", or \"qr!\\p{na=/(SMILING|GRINNING) FACE/}!\"",
                        "lines": 7
                    },
                    {
                        "name": "Improvement of \"POSIX::mblen()\", \"mbtowc\", and \"wctomb\"",
                        "lines": 16
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                    {
                        "name": "Alpha assertions are no longer experimental",
                        "lines": 5
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                    {
                        "name": "Script runs are no longer experimental",
                        "lines": 4
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                    {
                        "name": "Feature checks are now faster",
                        "lines": 4
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                    {
                        "name": "Perl is now developed on GitHub",
                        "lines": 5
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                        "name": "Compiled patterns can now be dumped before optimization",
                        "lines": 6
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                "name": "Security",
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                    {
                        "name": "[CVE-2020-10543] Buffer overflow caused by a crafted regular expression",
                        "lines": 11
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                    {
                        "name": "[CVE-2020-10878] Integer overflow via malformed bytecode produced by a crafted regular expression",
                        "lines": 7
                    },
                    {
                        "name": "[CVE-2020-12723] Buffer overflow caused by a crafted regular expression",
                        "lines": 6
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                        "name": "Additional Note",
                        "lines": 5
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                        "name": "Incompatible Changes",
                        "lines": 1
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                        "name": "Certain pattern matching features are now prohibited in compiling Unicode property value wildcard",
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                    {
                        "name": "Unused functions \"POSIX::mbstowcs\" and \"POSIX::wcstombs\" are removed",
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                    {
                        "name": "A bug fix for \"(?[...])\" may have caused some patterns to no longer compile",
                        "lines": 14
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                    {
                        "name": "Modifiable variables are no longer permitted in constants",
                        "lines": 15
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                    {
                        "name": "Use of \"vec\" on strings with code points above 0xFF is forbidden",
                        "lines": 3
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                    {
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                        "lines": 3
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                        "lines": 2
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                        "name": "Plain \"0\" string now treated as a number for range operator",
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                        "name": "Selected Bug Fixes",
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                "name": "Obituary",
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                        "name": "Reporting Bugs",
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                        "name": "Give Thanks",
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