New perldelta for 5.37.8

1 files changed, 279 insertions, 183 deletions

diff --git a/pod/perldelta.pod b/pod/perldelta.pod
index 4f44bac108..878f38d252 100644
--- a/pod/perldelta.pod
+++ b/pod/perldelta.pod
@@ -2,143 +2,177 @@
 
 =head1 NAME
 
-perldelta - what is new for perl v5.37.7
+[ this is a template for a new perldelta file.  Any text flagged as XXX needs
+to be processed before release. ]
+
+perldelta - what is new for perl v5.37.8
 
 =head1 DESCRIPTION
 
-This document describes differences between the 5.37.6 release and the 5.37.7
+This document describes differences between the 5.37.7 release and the 5.37.8
 release.
 
-If you are upgrading from an earlier release such as 5.37.5, first read
-L<perl5376delta>, which describes differences between 5.37.5 and 5.37.6.
+If you are upgrading from an earlier release such as 5.37.6, first read
+L<perl5377delta>, which describes differences between 5.37.6 and 5.37.7.
+
+=head1 Notice
+
+XXX Any important notices here
 
 =head1 Core Enhancements
 
-=head2 Defined-or and logical-or assignment default expressions to signatures
-
-The default expression for a subroutine signature parameter can now be
-assigned using the C<//=> or C<||=> operators, to apply the defaults whenever
-the caller provided an undefined or false value (respectively), rather than
-simply when the parameter is missing entirely.  For more detail see the
-documentation in L<perlsub>.
-
-=head2 @INC Hook Enhancements and $INC and INCDIR
-
-The internals for C<@INC> hooks have been hardened to handle various
-edge cases and should no longer segfault or throw assert failures when
-hooks modify C<@INC> during a require operation.  As part of this we
-now ensure that any given hook is executed at most once during a require
-call, and that any duplicate directories do not trigger additional
-directory probes.
-
-To provide developers more control over dynamic module lookup, a new hook
-method C<INCDIR> is now supported. An object supporting this method may be
-injected into the C<@INC> array, and when it is encountered in the module
-search process it will be executed, just like how INC hooks are executed,
-and its return value used as a list of directories to search for the
-module. Returning an empty list acts as a no-op. Note that since any
-references returned by this hook will be stringified and used as strings,
-you may not return a hook to be executed later via this API.
-
-When an C<@INC> hook (either C<INC> or C<INCDIR>) is called during
-require, the C<$INC> variable will be localized to be the value of the
-index of C<@INC> that the hook came from. If the hook wishes to override
-what the "next" index in C<@INC> should be it may update C<$INC> to be one
-less than the desired index (C<undef> is equivalent to C<-1>). This
-allows an C<@INC> hook to completely rewrite the C<@INC> array and have
-perl restart its directory probes from the beginning of C<@INC>.
-
-Blessed CODE references in C<@INC> that do not support the C<INC> or
-C<INCDIR> methods will no longer trigger an exception, and instead will
-be treated the same as unblessed coderefs are, and executed as though
-they were an C<INC> hook.
-
-=head2 Forbidden control flow out of C<defer> or C<finally> now detected at compile-time
-
-It is forbidden to attempt to leave a C<defer> or C<finally> block by means
-of control flow such as C<return> or C<goto>. Previous versions of perl could
-only detect this when actually attempted at runtime.
-
-This version of perl adds compile-time detection for many cases that can be
-statically determined. This may mean that code which compiled successfully on
-a previous version of perl is now reported as a compile-time error with this
-one. This only happens in cases where it would have been an error to actually
-execute the code anyway; the error simply happens at an earlier time.
+XXX New core language features go here.  Summarize user-visible core language
+enhancements.  Particularly prominent performance optimisations could go
+here, but most should go in the L</Performance Enhancements> section.
 
-=head1 Modules and Pragmata
+[ List each enhancement as a =head2 entry ]
 
-=head2 Updated Modules and Pragmata
+=head1 Security
+
+XXX Any security-related notices go here.  In particular, any security
+vulnerabilities closed should be noted here rather than in the
+L</Selected Bug Fixes> section.
+
+[ List each security issue as a =head2 entry ]
+
+=head1 Incompatible Changes
+
+XXX For a release on a stable branch, this section aspires to be:
+
+    There are no changes intentionally incompatible with 5.XXX.XXX
+    If any exist, they are bugs, and we request that you submit a
+    report.  See L</Reporting Bugs> below.
+
+[ List each incompatible change as a =head2 entry ]
+
+=head1 Deprecations
+
+XXX Any deprecated features, syntax, modules etc. should be listed here.
+
+=head2 Module removals
+
+XXX Remove this section if not applicable.
+
+The following modules will be removed from the core distribution in a
+future release, and will at that time need to be installed from CPAN.
+Distributions on CPAN which require these modules will need to list them as
+prerequisites.
+
+The core versions of these modules will now issue C<"deprecated">-category
+warnings to alert you to this fact.  To silence these deprecation warnings,
+install the modules in question from CPAN.
+
+Note that these are (with rare exceptions) fine modules that you are encouraged
+to continue to use.  Their disinclusion from core primarily hinges on their
+necessity to bootstrapping a fully functional, CPAN-capable Perl installation,
+not usually on concerns over their design.
+
+=over
+
+=item XXX
+
+XXX Note that deprecated modules should be listed here even if they are listed
+as an updated module in the L</Modules and Pragmata> section.
+
+=back
+
+[ List each other deprecation as a =head2 entry ]
+
+=head1 Performance Enhancements
+
+XXX Changes which enhance performance without changing behaviour go here.
+There may well be none in a stable release.
+
+[ List each enhancement as an =item entry ]
 
 =over 4
 
 =item *
 
-L<B::Deparse> has been upgraded from version 1.71 to 1.72.
+XXX
 
-=item *
+=back
+
+=head1 Modules and Pragmata
 
-L<experimental> has been upgraded from version 0.029 to 0.030.
+XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
+go here.  If Module::CoreList is updated, generate an initial draft of the
+following sections using F<Porting/corelist-perldelta.pl>.  A paragraph summary
+for important changes should then be added by hand.  In an ideal world,
+dual-life modules would have a F<Changes> file that could be cribbed.
 
-=item *
+The list of new and updated modules is modified automatically as part of
+preparing a Perl release, so the only reason to manually add entries here is if
+you're summarising the important changes in the module update. (Also, if the
+manually-added details don't match the automatically-generated ones, the
+release manager will have to investigate the situation carefully.)
 
-L<ExtUtils::Miniperl> has been upgraded from version 1.12 to 1.13.
+[ Within each section, list entries as an =item entry ]
 
-=item *
+=head2 New Modules and Pragmata
 
-L<ExtUtils::ParseXS> has been upgraded from version 3.48 to 3.49.
+=over 4
 
 =item *
 
-L<ExtUtils::Typemaps> has been upgraded from version 3.48 to 3.49.
+XXX Remove this section if not applicable.
 
-=item *
+=back
 
-L<feature> has been upgraded from version 1.77 to 1.78.
+=head2 Updated Modules and Pragmata
+
+=over 4
 
 =item *
 
-L<File::Glob> has been upgraded from version 1.38 to 1.39.
+L<XXX> has been upgraded from version A.xx to B.yy.
 
-=item *
+If there was something important to note about this change, include that here.
 
-L<File::Spec> has been upgraded from version 3.86 to 3.88.
+=back
 
-=item *
+=head2 Removed Modules and Pragmata
 
-L<Module::CoreList> has been upgraded from version 5.20221120 to 5.20221220.
+=over 4
 
 =item *
 
-L<Opcode> has been upgraded from version 1.62 to 1.63.
+XXX
 
-=item *
+=back
 
-L<parent> has been upgraded from version 0.238 to 0.239.
+=head1 Documentation
 
-=item *
+XXX Changes to files in F<pod/> go here.  Consider grouping entries by
+file and be sure to link to the appropriate page, e.g. L<perlfunc>.
 
-L<Pod::Html> has been upgraded from version 1.33 to 1.34.  Three auxiliary
-subroutines previously importable from Pod::Html must now be imported from
-Pod::Html::Util.
+=head2 New Documentation
 
-=item *
+XXX Changes which create B<new> files in F<pod/> go here.
 
-L<podlators> has been upgraded from version 4.14 to 5.00.
+=head3 L<XXX>
 
-=item *
+XXX Description of the purpose of the new file here
 
-L<POSIX> has been upgraded from version 2.08 to 2.10.  All fields known
-to the platform in L<localeconv(3)> are now returned by
-L<POSIX/localeconv>.  Previously, empty string fields and numeric fields
-that aren't applicable to the current locale were omitted.
+=head2 Changes to Existing Documentation
 
-=item *
+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>.
+
+XXX Changes which significantly change existing files in F<pod/> go here.
+However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
+section.
+
+Additionally, the following selected changes have been made:
 
-L<threads> has been upgraded from version 2.32 to 2.33.
+=head3 L<XXX>
+
+=over 4
 
 =item *
 
-L<XS::APItest> has been upgraded from version 1.27 to 1.28.
+XXX Description of the change here
 
 =back
 
@@ -148,166 +182,228 @@ 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>.
 
+XXX New or changed warnings emitted by the core's C<C> code go here.  Also
+include any changes in L<perldiag> that reconcile it to the C<C> code.
+
 =head2 New Diagnostics
 
+XXX Newly added diagnostic messages go under here, separated into New Errors
+and New Warnings
+
 =head3 New Errors
 
 =over 4
 
 =item *
 
-L<Object with arguments in @INC does not support a hook method
- |perldiag/"Object with arguments in @INC does not support a hook method">
+XXX L<message|perldiag/"message">
+
+=back
+
+=head3 New Warnings
+
+=over 4
+
+=item *
+
+XXX L<message|perldiag/"message">
 
 =back
 
 =head2 Changes to Existing Diagnostics
 
+XXX Changes (i.e. rewording) of diagnostic messages go here
+
+=over 4
+
+=item *
+
+XXX Describe change here
+
+=back
+
+=head1 Utility Changes
+
+XXX Changes to installed programs such as F<perldoc> and F<xsubpp> go here.
+Most of these are built within the directory F<utils>.
+
+[ List utility changes as a =head2 entry for each utility and =item
+entries for each change
+Use L<XXX> with program names to get proper documentation linking. ]
+
+=head2 L<XXX>
+
+=over 4
+
+=item *
+
+XXX
+
+=back
+
+=head1 Configuration and Compilation
+
+XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
+go here.  Any other changes to the Perl build process should be listed here.
+However, any platform-specific changes should be listed in the
+L</Platform Support> section, instead.
+
+[ List changes as an =item entry ].
+
 =over 4
 
 =item *
 
-The error message that is produced when a C<require> or C<use> statement
-fails has been changed. It used to contain the words C<@INC contains:>,
-and it used to show the state of C<@INC> *after* the require had
-completed and failed. The error message has been changed to say C<@INC
-entries checked:> and to reflect the actual directories or hooks that
-were executed during the require statement. For example:
-
-    perl -e'push @INC, sub {@INC=()}; eval "require Frobnitz"
-        or die $@'
-    Can't locate Frobnitz.pm in @INC (you may need to install the
-    Frobnitz module) (@INC contains:) at (eval 1) line 1.
-
-Will change to (with some output elided for clarity):
-
-    perl -e'push @INC, sub {@INC=()}; eval "require Frobnitz"
-        or die $@'
-    Can't locate Frobnitz.pm in @INC (you may need to install the
-    Frobnitz module) (@INC entries checked:
-    .../site_perl/5.37.7/x86_64-linux .../site_perl/5.37.7
-    .../5.37.7/x86_64-linux .../5.37.7 CODE(0x562745e684b8))
-    at (eval 1) line 1.
-
-thus showing the actual directories checked. Code that checks for
-C<@INC contains:> in error messages should be hardened against any future
-wording changes between the C<@INC> and C<:>, for instance use
-C<qr/\@INC[ \w]+:/> instead of using C<qr/\@INC contains:/> or
-C<qr/\@INC entries checked:/> in tests as this will ensure both forward
-and backward compatibility.
+XXX
 
 =back
 
 =head1 Testing
 
+XXX Any significant changes to the testing of a freshly built perl should be
+listed here.  Changes which create B<new> files in F<t/> go here as do any
+large changes to the testing harness (e.g. when parallel testing was added).
+Changes to existing files in F<t/> aren't worth summarizing, although the bugs
+that they represent may be covered elsewhere.
+
+XXX If there were no significant test changes, say this:
+
 Tests were added and changed to reflect the other additions and changes
 in this release.
 
-=head1 Internal Changes
+XXX If instead there were significant changes, say this:
+
+Tests were added and changed to reflect the other additions and
+changes in this release.  Furthermore, these significant changes were
+made:
+
+[ List each test improvement as an =item entry ]
 
 =over 4
 
 =item *
 
-The regex engine compilation code was split up into smaller sized compilation
-units. No functionality changes were made. This was just to make it easier
-to maintain the codebase.
+XXX
 
 =back
 
-=head1 Selected Bug Fixes
+=head1 Platform Support
+
+XXX Any changes to platform support should be listed in the sections below.
+
+[ Within the sections, list each platform as an =item entry with specific
+changes as paragraphs below it. ]
+
+=head2 New Platforms
+
+XXX List any platforms that this version of perl compiles on, that previous
+versions did not.  These will either be enabled by new files in the F<hints/>
+directories, or new subdirectories and F<README> files at the top level of the
+source tree.
 
 =over 4
 
-=item *
+=item XXX-some-platform
 
-Correctly handle C<OP_ANONCODE> ops generated by CPAN modules that
-don't include the OPf_REF flag when propagating lvalue context.
-L<[GH #20532]|https://github.com/Perl/perl5/pull/20532>
+XXX
 
-=item *
+=back
+
+=head2 Discontinued Platforms
+
+XXX List any platforms that this version of perl no longer compiles on.
+
+=over 4
 
-L<POSIX::strxfrm|POSIX/strxfrm> now uses the C<LC_CTYPE> locale category
-to specify its collation, ignoring any differing C<LC_COLLATE>.  It
-doesn't make sense for a string to be encoded in one locale (say,
-ISO-8859-6, Arabic) and to collate it based on another (like ISO-8859-7,
-Greek).  Perl assumes that the current C<LC_CTYPE> locale correctly
-represents the encoding, and collates accordingly.
+=item XXX-some-platform
 
-Also, embedded C<NUL> characters are now allowed in the input.
+XXX
 
-If locale collation is not enabled on the platform (C<LC_COLLATE>), the
-input is returned unchanged.
+=back
+
+=head2 Platform-Specific Notes
+
+XXX List any changes for specific platforms.  This could include configuration
+and compilation changes or changes in portability/compatibility.  However,
+changes within modules for platforms should generally be listed in the
+L</Modules and Pragmata> section.
+
+=over 4
+
+=item XXX-some-platform
+
+XXX
+
+=back
+
+=head1 Internal Changes
+
+XXX Changes which affect the interface available to C<XS> code go here.  Other
+significant internal changes for future core maintainers should be noted as
+well.
+
+[ List each change as an =item entry ]
+
+=over 4
 
 =item *
 
-Double FETCH during stringification of tied scalars returning an
-overloaded object have been fixed. The FETCH method should only be
-called once, but prior to this release was actually called twice.
-L<[GH #20574]|https://github.com/Perl/perl5/pull/20574>
+XXX
 
 =back
 
-=head1 Known Problems
+=head1 Selected Bug Fixes
+
+XXX Important bug fixes in the core language are summarized here.  Bug fixes in
+files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
+
+[ List each fix as an =item entry ]
 
 =over 4
 
 =item *
 
-CPAN modules not yet aware of new OPs
+XXX
 
-L<Devel::Caller>
-L<[RT #144051]|https://rt.cpan.org/Ticket/Display.html?id=144051>
-has not yet been updated to add awareness of new OPs introduced in
-this development cycle.
-L<[GH #20114]|https://github.com/Perl/perl5/issues/20114>. A patch has
-been submitted upstream but this has not been incorporated into a new
-release yet.
+=back
+
+=head1 Known Problems
 
-L<Test::Vars>
-L<[Test-Vars/GH #47]|https://github.com/houseabsolute/p5-Test-Vars/issues/47>
-also requires updating, but since this module's own tests are not
-failing, it is harder to determine how the new OPs should be
-accounted for. A potential patch has been submitted upstream, but
-awaits maintainer assessment.
+XXX Descriptions of platform agnostic bugs we know we can't fix go here.  Any
+tests that had to be C<TODO>ed for the release would be noted here.  Unfixed
+platform specific bugs also go here.
 
-L<Data::Alias>
-L<[RT #145279]|https://rt.cpan.org/Ticket/Display.html?id=145279> also
-requires updating to add awareness of new OPs. Investigation is pending
-and no patch has yet been submitted upstream.
+[ List each fix as an =item entry ]
+
+=over 4
+
+=item *
+
+XXX
 
 =back
 
-=head1 Acknowledgements
+=head1 Errata From Previous Releases
+
+=over 4
 
-Perl 5.37.7 represents approximately 4 weeks of development since Perl
-5.37.6 and contains approximately 42,000 lines of changes across 250 files
-from 20 authors.
+=item *
+
+XXX Add anything here that we forgot to add, or were mistaken about, in
+the perldelta of a previous release.
 
-Excluding auto-generated files, documentation and release tools, there were
-approximately 33,000 lines of changes to 140 .pm, .t, .c and .h files.
+=back
 
-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 5.37.7:
+=head1 Obituary
 
-Bart Van Assche, Craig A. Berry, Eric Herman, Felipe Gasper, Graham Knop,
-James E Keenan, Karl Williamson, Leon Timmermans, Matthew O. Persico, Max
-Maischein, Paul Evans, Philippe Bruhat (BooK), Richard Leach, Russ Allbery,
-Scott Baker, Tomasz Konojacki, Tony Cook, Tsuyoshi Watanabe, Yves Orton,
-Zakariyya Mughal.
+XXX If any significant core contributor or member of the CPAN community has
+died, add a short obituary here.
 
-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.
+=head1 Acknowledgements
 
-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.
+XXX Generate this with:
 
-For a more complete list of all of Perl's historical contributors, please
-see the F<AUTHORS> file in the Perl source distribution.
+  perl Porting/acknowledgements.pl v5.37.7..HEAD
 
 =head1 Reporting Bugs