phpman > man > perl5161delta(1)

PERL5161DELTA(1)                  Perl Programmers Reference Guide                  PERL5161DELTA(1)



NAME
       perl5161delta - what is new for perl v5.16.1

DESCRIPTION
       This document describes differences between the 5.16.0 release and the 5.16.1 release.

       If you are upgrading from an earlier release such as 5.14.0, first read perl5160delta, which
       describes differences between 5.14.0 and 5.16.0.

Security
   an off-by-two error in Scalar-List-Util has been fixed
       The bugfix was in Scalar-List-Util 1.23_04, and perl 5.16.1 includes Scalar-List-Util 1.25.

Incompatible Changes
       There are no changes intentionally incompatible with 5.16.0 If any exist, they are bugs, and
       we request that you submit a report.  See "Reporting Bugs" below.

Modules and Pragmata
   Updated Modules and Pragmata
       •   Scalar::Util and List::Util have been upgraded from version 1.23 to version 1.25.

       •   B::Deparse has been updated from version 1.14 to 1.14_01.  An "uninitialized" warning
           emitted by B::Deparse has been squashed [perl #113464].

Configuration and Compilation
       •   Building perl with some Windows compilers used to fail due to a problem with miniperl's
           "glob" operator (which uses the "perlglob" program) deleting the PATH environment
           variable [perl #113798].

Platform Support
   Platform-Specific Notes
       VMS All C header files from the top-level directory of the distribution are now installed on
           VMS, providing consistency with a long-standing practice on other platforms. Previously
           only a subset were installed, which broke non-core extension builds for extensions that
           depended on the missing include files.

Selected Bug Fixes
       •   A regression introduced in Perl v5.16.0 involving "tr/SEARCHLIST/REPLACEMENTLIST/" has
           been fixed.  Only the first instance is supposed to be meaningful if a character appears
           more than once in "SEARCHLIST".  Under some circumstances, the final instance was
           overriding all earlier ones.  [perl #113584]

       •   "B::COP::stashlen" has been added.   This provides access to an internal field added in
           perl 5.16 under threaded builds.  It was broken at the last minute before 5.16 was
           released [perl #113034].

       •   The re pragma will no longer clobber $_. [perl #113750]

       •   Unicode 6.1 published an incorrect alias for one of the Canonical_Combining_Class
           property's values (which range between 0 and 254).  The alias "CCC133" should have been
           "CCC132".  Perl now overrides the data file furnished by Unicode to give the correct
           value.

       •   Duplicating scalar filehandles works again.  [perl #113764]

       •   Under threaded perls, a runtime code block in a regular expression could corrupt the
           package name stored in the op tree, resulting in bad reads in "caller", and possibly
           crashes [perl #113060].

       •   For efficiency's sake, many operators and built-in functions return the same scalar each
           time.  Lvalue subroutines and subroutines in the CORE:: namespace were allowing this
           implementation detail to leak through.  "print &CORE::uc("a"), &CORE::uc("b")" used to
           print "BB".  The same thing would happen with an lvalue subroutine returning the return
           value of "uc".  Now the value is copied in such cases [perl #113044].

       •   "__SUB__" now works in special blocks ("BEGIN", "END", etc.).

       •   Formats that reference lexical variables from outside no longer result in crashes.

Known Problems
       There are no new known problems, but consult "Known Problems" in perl5160delta to see those
       identified in the 5.16.0 release.

Acknowledgements
       Perl 5.16.1 represents approximately 2 months of development since Perl 5.16.0 and contains
       approximately 14,000 lines of changes across 96 files from 8 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 5.16.1:

       Chris 'BinGOs' Williams, Craig A. Berry, Father Chrysostomos, Karl Williamson, Paul Johnson,
       Reini Urban, Ricardo Signes, 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 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.

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 v5.34.0                                 2025-07-25                             PERL5161DELTA(1)