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NAME

perldelta - what is new for perl v5.39.10

DESCRIPTION

This document describes differences between the 5.39.9 release and the 5.39.10 release.

If you are upgrading from an earlier release such as 5.39.8, first read perl5399delta, which describes differences between 5.39.8 and 5.39.9.

Core Enhancements

The :5.40 feature bundle adds try and extra_paired_delimiters

The latest version feature bundle now contains the recently-stablized features try and extra_paired_delimiters. As this feature bundle is used by the -E commandline switch, these are immediately available in -E scripts.

Modules and Pragmata

Updated Modules and Pragmata

  • B::Deparse has been upgraded from version 1.75 to 1.76.

  • Compress::Raw::Bzip2 has been upgraded from version 2.210 to 2.212.

  • Compress::Raw::Zlib has been upgraded from version 2.209 to 2.212.

  • experimental has been upgraded from version 0.031 to 0.032.

  • feature has been upgraded from version 1.86 to 1.88.

  • IO::Compress has been upgraded from version 2.207 to 2.212.

  • locale has been upgraded from version 1.11 to 1.12.

  • Module::CoreList has been upgraded from version 5.20240320 to 5.20240420.

  • podlators has been upgraded from version 5.01 to 5.01_01.

  • POSIX has been upgraded from version 2.18 to 2.19.

  • Socket has been upgraded from version 2.037 to 2.038.

  • Test2::Suite has been upgraded from version 0.000159 to 0.000162.

  • Test::Simple has been upgraded from version 1.302198 to 1.302199.

  • warnings has been upgraded from version 1.68 to 1.69.

  • XS::APItest has been upgraded from version 1.35 to 1.36.

Documentation

Changes to Existing Documentation

We have attempted to update the documentation to reflect the changes listed in this document. If you find any we have missed, open an issue at https://github.com/Perl/perl5/issues.

Additionally, the following selected changes have been made:

perlhacktips

  • Added brief documentation for some tools useful when developing perl itself on Windows or Cygwin.

Diagnostics

The following additions or changes have been made to diagnostic output, including warnings and fatal error messages. For the complete list of diagnostic messages, see perldiag.

New Diagnostics

New Errors

  • Cannot create an object of incomplete class "%s"

    (F) An attempt was made to create an object of a class where the start of the class definition has been seen, but the class has not been completed.

    This can happen for a failed eval, or if you attempt to create an object at compile time before the class is complete:

      eval "class Foo {"; Foo->new; # error
      class Bar { BEGIN { Bar->new } }; # error

    Previously perl would assert or crash. [github #22159]

Changes to Existing Diagnostics

Configuration and Compilation

  • You can now separately enable high water mark checks for non-DEBUGGING or disable them for DEBUGGING builds with -Accflags=-DPERL_USE_HWM or -Accflags=-DPERL_NO_HWM respectively. The default remains the same. [github #16607]

Selected Bug Fixes

  • prepare_export_lexical() was separately saving PL_comppad and PL_curpad, this could result in PL_curpad being restored to a no longer valid value, resulting in a panic when importing lexicals in some cases. [github #21981]

  • A string eval() operation in the scope of a use VERSION declaration would sometimes emit spurious "Changing use VERSION" warnings due to an inconsistency in the way the version number was stored. This is now fixed. [github #22121]

Known Problems

  • fork() failures on cygwin with -DDEBUGGING builds.

    Perl uses the --enable-auto-image-base option to set the base images for DLLs for cygperl5_39_10.dll and the DLLs needed for dynamically loaded modules on cygwin.

    With 5.39.10 if perl is built with -DDEBUGGING or possibly other options that increase the address space used by cygperl5_39_10.dll, the address space for cygperl5_39_10.dll overlaps with the address space allocated for mro.dll.

    The mro module will still load, but if perl attempts to fork you will likely see an error like:

     0 [main] perl 34054 child_info_fork::abort: address space needed by \
        'mro.dll' (0x400000) is already occupied

    You can workaround this by building without the -DDEBUGGING option, or by making mro a static extension:

      ./Configure ... -Astatic_ext=mro

    We expect the name change of the cygperl5_39_10.dll to cygperl5_39_11.dll in 5.39.11 will fix this problem for the next release. [github #22104]

Acknowledgements

Perl 5.39.10 represents approximately 5 weeks of development since Perl 5.39.9 and contains approximately 7,000 lines of changes across 380 files from 15 authors.

Excluding auto-generated files, documentation and release tools, there were approximately 4,300 lines of changes to 320 .pm, .t, .c and .h files.

Perl continues to flourish into its fourth decade thanks to a vibrant community of users and developers. The following people are known to have contributed the improvements that became Perl 5.39.10:

Bernard Quatermass, Craig A. Berry, Dagfinn Ilmari Mannsåker, David Mitchell, Elvin Aslanov, Graham Knop, H.Merijn Brand, James E Keenan, Karl Williamson, Lukas Mai, Paul Evans, TAKAI Kousuke, Tomasz Konojacki, Tony Cook, Yves Orton.

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 perl bug database at https://github.com/Perl/perl5/issues. There may also be information at https://www.perl.org/, the Perl Home Page.

If you believe you have an unreported bug, please open an issue at https://github.com/Perl/perl5/issues. Be sure to trim your bug down to a tiny but sufficient test case.

If the bug you are reporting has security implications which make it inappropriate to send to a public issue tracker, then see "SECURITY VULNERABILITY CONTACT INFORMATION" in perlsec for details of how to report the issue.

Give Thanks

If you wish to thank the Perl 5 Porters for the work we had done in Perl 5, you can do so by running the perlthanks program:

    perlthanks

This will send an email to the Perl 5 Porters list with your show of thanks.

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.