=encoding utf8

=head1 NAME

perl5436delta - what is new for perl v5.43.6

=head1 DESCRIPTION

This document describes differences between the 5.43.5 release and the 5.43.6
release.

If you are upgrading from an earlier release such as 5.43.4, first read
L<perl5435delta>, which describes differences between 5.43.4 and 5.43.5.

=head1 Deprecations

=over 4

=item *

Using C<goto> to jump into the body of a loop or other block construct from
outside is no longer permitted.
[L<GH #23618|https://github.com/Perl/perl5/issues/23618>]

=back

=head1 Modules and Pragmata

=head2 Updated Modules and Pragmata

=over 4

=item *

L<charnames> has been upgraded from version 1.50 to 1.51.

=item *

L<ExtUtils::ParseXS> has been upgraded from version 3.60 to 3.61.

=item *

L<ExtUtils::Typemaps> has been upgraded from version 3.60 to 3.61.

=item *

L<Module::CoreList> has been upgraded from version 5.20251120 to 5.20251220.

=item *

L<Term::Table> has been upgraded from version 0.027 to 0.028.

=item *

L<Test::Simple> has been upgraded from version 1.302216 to 1.302219.

=item *

L<warnings> has been upgraded from version 1.75 to 1.76.

=item *

L<XS::APItest> has been upgraded from version 1.47 to 1.48.

=back

=head1 Documentation

=head2 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
L<https://github.com/Perl/perl5/issues>.

Additionally, the following selected changes have been made:

=head3 L<perlxs>

=over 4

=item *

The reference manual for writing Perl XS code has been completely rewritten and
modernized.  It is about twice the size of the old file, and promotes more
modern XS syntax, such as ANSI signatures.

=back

=head1 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 L<perldiag>.

=head2 New Diagnostics

=head3 New Errors

=over 4

=item *

L<Use of "goto" to jump into a construct is no longer permitted|perldiag/"Use of "goto" to jump into a construct is no longer permitted">

(F) You have used C<goto LABEL;> or C<goto EXPR;> in an attempt to jump into
the body of a loop or other block construct from the outside.  As of Perl 5.44,
this throws an exception.

=back

=head2 Changes to Existing Diagnostics

=over 4

=item *

The error C<Unrecognised parameters for "%s" constructor: %s> has been changed
to C<Unrecognized parameters for "%s" constructor: %s>.

=item *

The deprecation warning
C<Attempt to call undefined %s method with arguments ("%s"%s) via package "%s" (Perhaps you forgot to load the package?)>
has been changed to
C<Attempt to call undefined %s method with arguments via package "%s" (Perhaps you forgot to load the package?)>
and is now a fatal error.

=back

=head1 Testing

Tests were added and changed to reflect the other additions and changes in this
release.

=head1 Platform Support

=head2 Platform-Specific Notes

=over 4

=item Windows

A compilation error in unthreaded builds using MSVC introduced in Perl 5.43.5
has been fixed.  [L<GH #23952|https://github.com/Perl/perl5/issues/23952>]

=back

=head1 Internal Changes

=over 4

=item *

C<Perl_sv_backoff>, which undoes the OOK string offset mechanism now only moves
the string buffer contents to the start of the buffer if `SvOK(sv)` is true.
Historically, the buffer contents were always moved, but if the buffer contents
are defunct and no longer required, doing that incurs an unnecessary cost
proportional to the size of the shifted contents.

(The assumption in this change is that `SvOK(sv)` is a valid indicator of
whether the string buffer contents are "live" or not.)

See [L<GH #23967|https://github.com/Perl/perl5/issues/23967>] for an example of
where such a copy was noticeable.

=item *

The XS parser, L<ExtUtils::ParseXS>, has been further extensively restructured
internally.  Most of these changes shouldn't be visible externally, but might
affect XS code which was using invalid or unsupported syntax.  Several minor
bug-fixes were included.

=back

=head1 Selected Bug Fixes

=over 4

=item *

Regexes which include both a sub-pattern (e.g. C<(??{...})> or C<(?&FOO)>) and
a cut (i.e. C<< (?>...) >>) could sometimes cause a premature scope exit in
other code during a match.  For example, in something like
C<(?{ local $x = ... })>, the C<local> might have been unwound before the
pattern has finished matching.
[L<GH #16197|https://github.com/Perl/perl5/issues/16197>]

=item *

C<DB::sub> is not meant to be called for sub calls from the DB package, but
called to overloaded subs for overloaded values used in the DB package would
result in calls in DB::sub.  Fixed the check for the current package in
amagic_call().  [L<GH #24001|https://github.com/Perl/perl5/issues/24001>]

=item *

pregexec() handles zero-length strings again, fixing an assert failure in
Package-Stash-XS (which Moose depends upon).  This had been broken in Perl
5.43.4.  [L<GH #23903|https://github.com/Perl/perl5/issues/23903>]

=back

=head1 Acknowledgements

Perl 5.43.6 represents approximately 4 weeks of development since Perl 5.43.5
and contains approximately 25,000 lines of changes across 330 files from 17
authors.

Excluding auto-generated files, documentation and release tools, there were
approximately 11,000 lines of changes to 280 .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 5.43.6:

Bartosz Jarzyna, Chad Granum, Chris 'BinGOs' Williams, Dan Book, David
Mitchell, Eric Herman, James E Keenan, James Raspass, Karl Williamson, Max
Maischein, Paul Evans, Philippe Bruhat (BooK), Richard Leach, Steve Hay, TAKAI
Kousuke, Thibault Duponchelle, 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 F<AUTHORS> file in the Perl source distribution.

=head1 Reporting Bugs

If you find what you think is a bug, you might check the perl bug database at
L<https://github.com/Perl/perl5/issues>.  There may also be information at
L<https://www.perl.org/>, the Perl Home Page.

If you believe you have an unreported bug, please open an issue at
L<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
L<perlsec/SECURITY VULNERABILITY CONTACT INFORMATION> for details of how to
report the issue.

=head1 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 C<perlthanks> program:

    perlthanks

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

=head1 SEE ALSO

The F<Changes> file for an explanation of how to view exhaustive details on
what changed.

The F<INSTALL> file for how to build Perl.

The F<README> file for general stuff.

The F<Artistic> and F<Copying> files for copyright information.

=cut
