man > perl5125delta(1)

PERL5125DELTA(1)                  Perl Programmers Reference Guide                  PERL5125DELTA(1)

NAME
       perl5125delta - what is new for perl v5.12.5

DESCRIPTION
       This document describes differences between the 5.12.4 release and the 5.12.5 release.

       If you are upgrading from an earlier release such as 5.12.3, first read perl5124delta, which
       describes differences between 5.12.3 and 5.12.4.

Security
   "Encode" decode_xs n-byte heap-overflow (CVE-2011-2939)
       A bug in "Encode" could, on certain inputs, cause the heap to overflow.  This problem has
       been corrected.  Bug reported by Robert Zacek.

   File::Glob::bsd_glob() memory error with GLOB_ALTDIRFUNC (CVE-2011-2728).
       Calling "File::Glob::bsd_glob" with the unsupported flag GLOB_ALTDIRFUNC would cause an
       access violation / segfault.  A Perl program that accepts a flags value from an external
       source could expose itself to denial of service or arbitrary code execution attacks.  There
       are no known exploits in the wild.  The problem has been corrected by explicitly disabling
       all unsupported flags and setting unused function pointers to null.  Bug reported by Clément
       Lecigne.

   Heap buffer overrun in 'x' string repeat operator (CVE-2012-5195)
       Poorly written perl code that allows an attacker to specify the count to perl's 'x' string
       repeat operator can already cause a memory exhaustion denial-of-service attack. A flaw in
       versions of perl before 5.15.5 can escalate that into a heap buffer overrun; coupled with
       versions of glibc before 2.16, it possibly allows the execution of arbitrary code.

       This problem has been fixed.

Incompatible Changes
       There are no changes intentionally incompatible with 5.12.4. If any exist, they are bugs and
       reports are welcome.

Modules and Pragmata
   Updated Modules
       B::Concise

       B::Concise no longer produces mangled output with the -tree option [perl #80632].

       charnames

       A regression introduced in Perl 5.8.8 has been fixed, that caused charnames::viacode(0) to
       return "undef" instead of the string "NULL" [perl #72624].

       Encode has been upgraded from version 2.39 to version 2.39_01.

       See "Security".

       File::Glob has been upgraded from version 1.07 to version 1.07_01.

       See "Security".

       Unicode::UCD

       The documentation for the "upper" function now actually says "upper", not "lower".

       Module::CoreList

       Module::CoreList has been updated to version 2.50_02 to add data for this release.

Changes to Existing Documentation
   perlebcdic
       The perlebcdic document contains a helpful table to use in "tr///" to convert between EBCDIC
       and Latin1/ASCII.  Unfortunately, the table was the inverse of the one it describes.  This
       has been corrected.

   perlunicode
       The section on User-Defined Case Mappings had some bad markup and unclear sentences, making
       parts of it unreadable.  This has been rectified.

   perluniprops
       This document has been corrected to take non-ASCII platforms into account.

Installation and Configuration Improvements
   Platform Specific Changes
       Mac OS X
           There  have  been  configuration  and  test  fixes to make Perl build cleanly on Lion and
           Mountain Lion.

       NetBSD
           The NetBSD hints file was corrected to be compatible with NetBSD 6.*

Selected Bug Fixes
       •   "chop" now correctly handles characters above "\x{7fffffff}" [perl #73246].

       •   "($<,$>) = (...)" stopped working properly in 5.12.0.  It is supposed to  make  a  single
           setreuid() call, rather than calling setruid() and seteuid() separately.  Consequently it
           did not work properly.  This has been fixed [perl #75212].

       •   Fixed  a  regression  of  kill() when a match variable is used for the process ID to kill
           [perl #75812].

       •   "UNIVERSAL::VERSION" no longer leaks memory.  It started leaking in Perl 5.10.0.

       •   The C-level "my_strftime" functions no longer leaks memory.  This fixes a memory leak  in
           "POSIX::strftime" [perl #73520].

       •   "caller" no longer leaks memory when called from the DB package if @DB::args was assigned
           to after the first call to "caller".  Carp was triggering this bug [perl #97010].

       •   Passing  to  "index"  an  offset  beyond the end of the string when the string is encoded
           internally in UTF8 no longer causes panics [perl #75898].

       •   Syntax errors in "(?{...})" blocks in regular expressions no longer cause panic  messages
           [perl #2353].

       •   Perl  5.10.0 introduced some faulty logic that made "U*" in the middle of a pack template
           equivalent to "U0" if the input string was empty.  This has been fixed [perl #90160].

Errata
   split() and @_
       split() no longer modifies @_ when called in scalar or void context.  In void context it  now
       produces  a  "Useless  use  of  split" warning.  This is actually a change introduced in perl
       5.12.0, but it was missed from that release's perl5120delta.

Acknowledgements
       Perl 5.12.5 represents approximately 17 months of development since Perl 5.12.4 and  contains
       approximately 1,900 lines of changes across 64 files from 18 authors.

       Perl  continues  to flourish into its third decade thanks to a vibrant community of users and
       developers. The following people are known to have contributed the improvements  that  became
       Perl 5.12.5:

       Andy  Dougherty, Chris 'BinGOs' Williams, Craig A. Berry, David Mitchell, Dominic Hargreaves,
       Father  Chrysostomos,  Florian  Ragwitz,  George  Greer,  Goro  Fuji,  Jesse  Vincent,   Karl
       Williamson,  Leon Brocard, Nicholas Clark, Rafael Garcia-Suarez, Reini Urban, Ricardo Signes,
       Steve Hay, Tony Cook.

       The list above is almost certainly incomplete as it is automatically generated  from  version
       control  history. In particular, it does not include the names of the (very much appreciated)
       contributors who reported issues to the Perl bug tracker.

       Many of the changes included in this version originated  in  the  CPAN  modules  included  in
       Perl's core. We're grateful to the entire CPAN community for helping Perl to flourish.

       For  a  more  complete  list of all of Perl's historical contributors, please see the AUTHORS
       file in the Perl source distribution.

Reporting Bugs
       If you find what you think is a bug, you might check the  articles  recently  posted  to  the
       comp.lang.perl.misc  newsgroup  and  the  perl  bug database at http://rt.perl.org/perlbug/ .
       There may also be information at http://www.perl.org/ , the Perl Home Page.

       If you believe you have an unreported bug, please run the perlbug program included with  your
       release.  Be sure to trim your bug down to a tiny but sufficient test case.  Your bug report,
       along  with  the  output of "perl -V", will be sent off to perlbug AT perl.org to be analysed by
       the Perl porting team.

       If the bug you are reporting has security implications, which make it inappropriate  to  send
       to  a  publicly archived mailing list, then please send it to perl5-security-report AT perl.org.
       This points to a closed subscription unarchived mailing list, which  includes  all  the  core
       committers,  who  be  able  to help assess the impact of issues, figure out a resolution, and
       help co-ordinate the release of patches to mitigate or fix the problem across  all  platforms
       on  which  Perl  is  supported.  Please only use this address for security issues in the Perl
       core, not for modules independently distributed on CPAN.

SEE ALSO
       The Changes file for an explanation of how to view exhaustive details on what changed.

       The INSTALL file for how to build Perl.

       The README file for general stuff.

       The Artistic and Copying files for copyright information.

perl v5.38.2                                 2026-08-18                             PERL5125DELTA(1)