++ed by:

173 PAUSE users
161 non-PAUSE users.

Ricardo SIGNES 😄
and 1 contributors


perldelta - what is new for perl v5.17.11


This document describes differences between the 5.17.10 release and the 5.17.11 release.

If you are upgrading from an earlier release such as 5.17.9, first read perl51710delta, which describes differences between 5.17.9 and 5.17.10.

Incompatible Changes

Although no major incompatibilities have been introduced, the "switch" family of features have been marked experimental and will now emit warnings. These are: the ~~ operator, given, and when.

Modules and Pragmata

Updated Modules and Pragmata

  • Fixed the merge of ExtUtils-MakeMaker 6.65_01 to remove an excluded file. This was causing a test failure on Win32 [perl #117477]

  • B::Deparse has been upgraded from version 1.19 to 1.20, adding stub deparsing for lexical subroutines.

  • bigint has been upgraded from version 0.33 to 0.34.

  • CPAN has been upgraded from its trial 2.00 release to its final 2.00 release.

  • Exporter has been upgraded from version 5.67 to 5.68.

  • ExtUtils::CBuilder has been upgraded from version 0.280209 to 0.280210.

  • ExtUtils::MakeMaker has been upgraded from version 6.65_01 to 6.66.

  • IO has been upgraded from version 1.27 to 1.28.

  • overload has been upgraded from version 1.21 to 1.22.

  • Storable has been upgraded from version 2.40 to 2.41.

  • warnings has been upgraded from version 1.17 to 1.18.

Changes to Existing Documentation

Asian-language documentation

The Asian-language documentation, previously stored in a few different encodings, have been transcoded to UTF-8.


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 Warnings

Platform Support

Platform-Specific Notes


As of 5.18.0, Perl on VMS can (at last) be built in and installed from a directory having dots in the name, so it is no longer necessary to rename the top-level source directory before building.

The pertinent instructions have been removed from README.vms, so we also no longer need to update the version number that was embedded in those instructions.

Selected Bug Fixes

Make vms.c's Perl_flex_fstat preserve errno on success
split's first argument is more consistently interpreted

After some changes earlier in 5.17, split's behavior has been simplified: if the PATTERN argument evaluates to a literal string containing one space, it is treated the way that a literal string containing one space once was.

Handle overloading properly in compile-time regex

(?{…}) and qr constant overloading did not play nicely together, and when qr constant overloading was in effect, qr constructs inside a (?{…}) construct were incorrectly interpreted. [perl #116823]


Perl 5.17.11 represents approximately 4 weeks of development since Perl 5.17.10 and contains approximately 3,800 lines of changes across 130 files from 17 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 5.17.11:

Aaron Crane, Andy Dougherty, Brian Fraser, Chris 'BinGOs' Williams, Craig A. Berry, David Mitchell, François Perrad, James E Keenan, Jan Dubois, Karl Williamson, Leon Timmermans, Max Maischein, Moritz Lenz, Nicholas Clark, Ricardo Signes, 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 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@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@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.


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.