Provided by: perl-doc_5.26.2-7_all bug


       perl5181delta - what is new for perl v5.18.1


       This document describes differences between the 5.18.0 release and the 5.18.1 release.

       If you are upgrading from an earlier release such as 5.16.0, first read perl5180delta,
       which describes differences between 5.16.0 and 5.18.0.

Incompatible Changes

       There are no changes intentionally incompatible with 5.18.0 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
       ·   B has been upgraded from 1.42 to 1.42_01, fixing bugs related to lexical subroutines.

       ·   Digest::SHA has been upgraded from 5.84 to 5.84_01, fixing a crashing bug.  [RT

       ·   Module::CoreList has been upgraded from 2.89 to 2.96.

Platform Support

   Platform-Specific Notes
       AIX A rarely-encounted configuration bug in the AIX hints file has been corrected.

           After a patch to the relevant hints file, perl should now build correctly on
           MidnightBSD 0.4-RELEASE.

Selected Bug Fixes

       ·   Starting in v5.18.0, a construct like "/[#](?{})/x" would have its "#" incorrectly
           interpreted as a comment.  The code block would be skipped, unparsed.  This has been

       ·   A number of memory leaks related to the new, experimental regexp bracketed character
           class feature have been plugged.

       ·   The OP allocation code now returns correctly aligned memory in all cases for "struct
           pmop". Previously it could return memory only aligned to a 4-byte boundary, which is
           not correct for an ithreads build with 64 bit IVs on some 32 bit platforms. Notably,
           this caused the build to fail completely on sparc GNU/Linux. [RT #118055]

       ·   The debugger's "man" command been fixed. It was broken in the v5.18.0 release. The
           "man" command is aliased to the names "doc" and "perldoc" - all now work again.

       ·   @_ is now correctly visible in the debugger, fixing a regression introduced in
           v5.18.0's debugger. [RT #118169]

       ·   Fixed a small number of regexp constructions that could either fail to match or crash
           perl when the string being matched against was allocated above the 2GB line on 32-bit
           systems. [RT #118175]

       ·   Perl v5.16 inadvertently introduced a bug whereby calls to XSUBs that were not visible
           at compile time were treated as lvalues and could be assigned to, even when the
           subroutine was not an lvalue sub.  This has been fixed.  [perl #117947]

       ·   Perl v5.18 inadvertently introduced a bug whereby dual-vars (i.e.  variables with both
           string and numeric values, such as $! ) where the truthness of the variable was
           determined by the numeric value rather than the string value. [RT #118159]

       ·   Perl v5.18 inadvertently introduced a bug whereby interpolating mixed up- and down-
           graded UTF-8 strings in a regex could result in malformed UTF-8 in the pattern:
           specifically if a downgraded character in the range "\x80..\xff" followed a UTF-8
           string, e.g.

               utf8::upgrade(  my $u = "\x{e5}");
               utf8::downgrade(my $d = "\x{e5}");

           [perl #118297].

       ·   Lexical constants ("my sub a() { 42 }") no longer crash when inlined.

       ·   Parameter prototypes attached to lexical subroutines are now respected when compiling
           sub calls without parentheses.  Previously, the prototypes were honoured only for
           calls with parentheses. [RT #116735]

       ·   Syntax errors in lexical subroutines in combination with calls to the same subroutines
           no longer cause crashes at compile time.

       ·   The dtrace sub-entry probe now works with lexical subs, instead of crashing [perl

       ·   Undefining an inlinable lexical subroutine ("my sub foo() { 42 } undef &foo") would
           result in a crash if warnings were turned on.

       ·   Deep recursion warnings no longer crash lexical subroutines. [RT #118521]


       Perl 5.18.1 represents approximately 2 months of development since Perl 5.18.0 and
       contains approximately 8,400 lines of changes across 60 files from 12 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 5.18.1:

       Chris 'BinGOs' Williams, Craig A. Berry, Dagfinn Ilmari Mannsåker, David Mitchell, Father
       Chrysostomos, Karl Williamson, Lukas Mai, Nicholas Clark, Peter Martini, Ricardo Signes,
       Shlomi Fish, 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 .
       There may also be information at , 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 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  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.