PERL5122DELTA(1)
π perl5122delta β what is new for perl v5.12.2 π
okay so bestie, welcome to a page from the Perl Programmers Reference Guide, and it's the whole entire tea on perl v5.12.2. let's get into it π«Ά
πΈ NAME πΈ
perl5122delta β what is new for perl v5.12.2. that's it, that's the name, no notes β¨
π¦ DESCRIPTION π¦
So this doc is describing the differences between the 5.12.1 release and the 5.12.2 release. that's the vibe. that's the whole scope. π
And if you're upgrading from an earlier major version β like, say, from 5.10.1 β then bestie please read perl5120delta first, because it describes the differences between 5.10.0 and 5.12.0. also read perl5121delta, which covers the earlier changes in the 5.12 stable release series. do it in order, trust me, iykyk π
π Incompatible Changes π
There are no changes intentionally incompatible with 5.12.1. literally none, we're being good.
If any exist? They're bugs, and reports are welcome. so if you find one, say something, we're listening π«Ά
π Core Enhancements π
Other than the bug fixes listed below, there should be no user-visible changes to the core language in this release. that's the whole section. she's lowkey serving "nothing to see here" and honestly? iconic π
π Modules and Pragmata π
π« New Modules and Pragmata π«
This release does not introduce any new modules or pragmata. none. zero. empty shelf. π
π§ Pragmata Changes π§
In the previous release, no VERSION; statements triggered a bug which could cause feature bundles to be loaded and strict mode to be enabled unintentionally. yeah. that was a whole thing. π
π Updated Modules π
Carp
Upgraded from version 1.16 to 1.17.
Carp now detects incomplete caller() overrides and avoids using bogus @DB::args. To provide backtraces, Carp relies on particular behaviour of the caller built-in. Carp now detects if other code has overridden this with an incomplete implementation, and modifies its backtrace accordingly. Previously incomplete overrides would cause incorrect values in backtraces (best case), or obscure fatal errors (worst case)
This fixes certain cases of Bizarre copy of ARRAY caused by modules overriding caller() incorrectly. no cap, that error message was living rent free in everyone's backtraces π
CPANPLUS
A patch to cpanp-run-perl has been backported from CPANPLUS 0.9004. This resolves RT #55964 http://rt.cpan.org/Public/Bug/Display.html?id=55964 and RT #57106 http://rt.cpan.org/Public/Bug/Display.html?id=57106, both of which related to failures to install distributions that use Module::Install::DSL. installs were failing and now they're not, we love a redemption arc β¨
File::Glob
A regression which caused a failure to find CORE::GLOBAL::glob after loading File::Glob to crash has been fixed. Now, it correctly falls back to external globbing via pp_glob. slay, fixed, moving on π¦
File::Copy
File::Copy::copy(FILE, DIR) is now documented. it was always there doing its thing, but now it's documented, which is basically a glow-up π
File::Spec
Upgraded from version 3.31 to 3.31_01.
Several portability fixes were made in File::Spec::VMS: a colon is now recognized as a delimiter in native filespecs; caret-escaped delimiters are recognized for better handling of extended filespecs; catpath() returns an empty directory rather than the current directory if the input directory name is empty; abs2rel() properly handles Unix-style input. VMS said "i contain multitudes" and honestly, respect π
π Utility Changes π
perlbugnow always gives the reporter a chance to change the email address it guesses for them. no more accidentally filing a bug as your old work email, we've all been there πperlbugshould no longer warn about uninitialized values when using the-dand-voptions. silence. blessed silence. π
π Changes to Existing Documentation π
- The existing policy on backward-compatibility and deprecation has been added to
perlpolicy, along with definitions of terms like deprecation. β¨ srandin perlfunc's usage has been clarified. π- The entry for
diein perlfunc was reorganized to emphasize its role in the exception mechanism. main character energy fr π - Perl's
INSTALLfile has been clarified to explicitly state that Perl requires a C89 compliant ANSI C Compiler. π§ IO::Socket'sgetsockopt()andsetsockopt()have been documented. π¦alarm()'s inability to interrupt blocking IO on Windows has been documented. πMath::TrulyRandomhasn't been updated since 1996 and has been removed as a recommended solution for random number generation. she's been un-recommended, it's giving retirement party πperlrunhas been updated to clarify the behaviour of octal flags to perl. πΈ- To ease user confusion,
$#and$*, two special variables that were removed in earlier versions of Perl have been documented. they're gone but not forgotten, now with paperwork π - The version of perlfaq shipped with the Perl core has been updated from the official FAQ version, which is now maintained in the
briandfoy/perlfaqbranch of the Perl repository atgit://perl5.git.perl.org/perl.git. π
π οΈ Installation and Configuration Improvements π οΈ
βοΈ Configuration improvements βοΈ
- The
d_u32alignconfiguration probe on ARM has been fixed. π₯
π§± Compilation improvements π§±
- An
"incompatible operand types"error in ternary expressions when building withclanghas been fixed. π¦ - Perl now skips setuid
File::Copytests on partitions it detects to be mounted asnosuid. π
π Selected Bug Fixes π
okay bestie this section is a whole bunch of "we fixed the thing" and honestly it's very satisfying. here we go:
- A possible segfault in the
T_PRTOBJdefault typemap has been fixed. πβ‘οΈπ - A possible memory leak when using
caller()to set@DB::argshas been fixed. π«Ά - Several memory leaks when loading XS modules were fixed. πΈ
unpack()now handles scalar context correctly for%32Hand%32u, fixing a potential crash.split()would crash because the third item on the stack wasn't the regular expression it expected.unpack("%2H", ...)would return both the unpacked result and the checksum on the stack, as wouldunpack("%2u", ...). [GH #10257]https://github.com/Perl/perl5/issues/10257π- Perl now avoids using memory after calling
free()inpp_requirewhen there are CODEREFs in@INC. π - A bug that could cause
"Unknown error"messages when"call_sv(code, G_EVAL)"is called from an XS destructor has been fixed. the most unhelpful error message of all time, finally addressed π - The implementation of the
open $fh, '>' \$bufferfeature now supports get/set magic and thus tied buffers correctly. β¨ - The
pp_getc,pp_tell, andpp_eofopcodes now make room on the stack for their return values in cases where no argument was passed in. π - When matching Unicode strings under some conditions inappropriate backtracking would result in a
Malformed UTF-8 character (fatal)error. This should no longer occur. See [GH #10434]https://github.com/Perl/perl5/issues/10434π
π Platform Specific Notes π
π§ AIX
README.aixhas been updated with information about the XL C/C++ V11 compiler suite. β¨
πͺ Windows
- When building Perl with the mingw64 x64 cross-compiler
incpath,libpth,ldflags,lddlflagsandldflags_nolargefilesvalues inConfig.pmandConfig_heavy.plwere not previously being set correctly because, with that compiler, the include and lib directories are not immediately below$(CCHOME). fixed now, bestie π
πΎ VMS
git_version.his now installed on VMS. This was an oversight in v5.12.0 which caused some extensions to fail to build. oopsie, corrected π«Ά- Several memory leaks in
stat()have been fixed. π¦ - A memory leak in
Perl_rename()due to a double allocation has been fixed. πΈ - A memory leak in
vms_fid_to_name()(used byrealpath()andrealname()) has been fixed. π
π«Ά Acknowledgements π«Ά
Perl 5.12.2 represents approximately three months of development since Perl 5.12.1 and contains approximately 2,000 lines of changes across 100 files from 36 authors. that's a lot of people doing a lot of little fixes and we are obsessed π
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 5.12.2:
Abigail, Γvar ArnfjΓΆrΓ° Bjarmason, Ben Morrow, brian d foy, Brian Phillips, Chas. Owens, Chris 'BinGOs' Williams, Chris Williams, Craig A. Berry, Curtis Jewell, Dan Dascalescu, David Golden, David Mitchell, Father Chrysostomos, Florian Ragwitz, George Greer, H.Merijn Brand, Jan Dubois, Jesse Vincent, Jim Cromie, Karl Williamson, Lars DΙͺα΄α΄α΄α΄α΄‘ θΏͺζζ―, Leon Brocard, Maik Hentsche, Matt S Trout, Nicholas Clark, Rafael Garcia-Suarez, Rainer Tammer, Ricardo Signes, Salvador Ortiz Garcia, Sisyphus, Slaven Rezic, Steffen Mueller, Tony Cook, Vincent Pit and Yves Orton.
every single one of them, we love them, periodt π
π Reporting Bugs π
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. β¨
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@perl.org to be analysed by the Perl porting team. pls pls pls make the test case small, the porters are begging π
Security stuff, listen up bestie: 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@perl.org. This points to a closed subscription unarchived mailing list, which includes all the core committers, who will 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. π
π SEE ALSO π
- The
Changesfile for an explanation of how to view exhaustive details on what changed. - The
INSTALLfile for how to build Perl. - The
READMEfile for general stuff. - The
ArtisticandCopyingfiles for copyright information.
and that's the whole page bestie π«Ά this was pulled from perl v5.42.3, dated 2026-08-03, and it's the PERL5122DELTA(1) page in all her glory. go forth and know what changed in 5.12.2 πβ¨π
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