new perldelta for 5.35.2

4 files changed, 536 insertions, 92 deletions

diff --git a/pod/.gitignore b/pod/.gitignore
index 7a85a81c2b..d9f19057f6 100644
--- a/pod/.gitignore
+++ b/pod/.gitignore
@@ -48,7 +48,7 @@
 /roffitall
 
 # generated
-/perl5351delta.pod
+/perl5352delta.pod
 /perlapi.pod
 /perlintern.pod
 /perlmodlib.pod
diff --git a/pod/perl.pod b/pod/perl.pod
index 9f168251de..477d05607d 100644
--- a/pod/perl.pod
+++ b/pod/perl.pod
@@ -179,6 +179,7 @@ aux h2ph h2xs perlbug pl2pm pod2html pod2man splain xsubpp
 
     perlhist		Perl history records
     perldelta		Perl changes since previous version
+    perl5351delta	Perl changes in version 5.35.1
     perl5350delta	Perl changes in version 5.35.0
     perl5340delta	Perl changes in version 5.34.0
     perl5321delta	Perl changes in version 5.32.1
diff --git a/pod/perl5351delta.pod b/pod/perl5351delta.pod
new file mode 100644
index 0000000000..c3abebd3ed
--- /dev/null
+++ b/pod/perl5351delta.pod
@@ -0,0 +1,239 @@
+=encoding utf8
+
+=head1 NAME
+
+perl5351delta - what is new for perl v5.35.1
+
+=head1 DESCRIPTION
+
+This document describes differences between the 5.35.0 release and the 5.35.1
+release.
+
+If you are upgrading from an earlier release such as 5.34.0, first read
+L<perl5350delta>, which describes differences between 5.34.0 and 5.35.0.
+
+=head1 Modules and Pragmata
+
+=head2 Updated Modules and Pragmata
+
+=over 4
+
+=item *
+
+L<B::Deparse> has been upgraded from version 1.56 to 1.57.
+
+=item *
+
+L<Data::Dumper> has been upgraded from version 2.179 to 2.181.
+
+=item *
+
+L<feature> has been upgraded from version 1.65 to 1.66.
+
+=item *
+
+L<File::Copy> has been upgraded from version 2.35 to 2.36.
+
+Inode numbers are now compared as strings, so that large inode numbers
+are correctly distinguished. (GH #18788)
+
+=item *
+
+L<File::Glob> has been upgraded from version 1.33 to 1.35.
+
+=item *
+
+L<File::Spec> has been upgraded from version 3.80 to 3.81.
+
+=item *
+
+L<File::stat> has been upgraded from version 1.09 to 1.10.
+
+=item *
+
+L<IO> has been upgraded from version 1.46 to 1.47.
+
+Implement sync() for win32.
+
+=item *
+
+L<Module::CoreList> has been upgraded from version 5.20210521 to 5.20210620.
+
+=item *
+
+L<Opcode> has been upgraded from version 1.50 to 1.51.
+
+=item *
+
+L<open> has been upgraded from version 1.12 to 1.13.
+
+=item *
+
+L<PathTools|Cwd> has been upgraded from version 3.80 to 3.81.
+
+Inodes numbers are now compared as strings, so that large inode numbers
+are correctly distinguished. (GH #18788)
+
+=item *
+
+L<perlfaq> has been upgraded from version 5.20210411 to 5.20210520.
+
+=item *
+
+L<POSIX> has been upgraded from version 1.97 to 1.98.
+
+=item *
+
+L<Scalar::Util> has been upgraded from version 1.55 to 1.56.
+
+=item *
+
+L<Socket> has been upgraded from version 2.031 to 2.032.
+
+=item *
+
+L<Test::Simple> has been upgraded from version 1.302183 to 1.302185.
+
+=item *
+
+L<Unicode::Collate> has been upgraded from version 1.29 to 1.30.
+
+One warning in F<mkheader> averted (rt.cpan.org #133952).
+
+=item *
+
+L<Unicode::UCD> has been upgraded from version 0.75 to 0.76.
+
+=item *
+
+L<version> has been upgraded from version 0.9928 to 0.9929.
+
+=item *
+
+L<XS::APItest> has been upgraded from version 1.16 to 1.17.
+
+=back
+
+=head2 Changes to Existing Diagnostics
+
+=over 4
+
+=item *
+
+L<Can't modify %s in %s|perldiag/"Can't modify %s in %s">
+(for scalar assignment to C<undef>)
+
+Attempting to perform a scalar assignment to C<undef>, for example via
+C<undef = $foo;>, previously triggered a fatal runtime error with the
+message "L<Modification of a read-only value attempted|perldiag/"Modification of a read-only value attempted">."
+It is more helpful to detect such attempted assignments prior to
+runtime, so they are now compile time errors, resulting in the message
+"Can't modify undef operator in scalar assignment".
+
+=back
+
+=head1 Internal Changes
+
+=over 4
+
+=item *
+
+Since the removal of PERL_OBJECT in Perl 5.8, PERL_IMPLICIT_CONTEXT and
+MULTIPLICITY have been synonymous and they were being used interchangeably.
+To simplify the code, all instances of PERL_IMPLICIT_CONTEXT have been
+replaced with MULTIPLICITY.
+
+PERL_IMPLICIT_CONTEXT will remain defined for compatibility with XS modules.
+
+=back
+
+=head1 Selected Bug Fixes
+
+=over 4
+
+=item *
+
+utime() now correctly sets errno/C<$!> when called on a closed handle.
+
+=item *
+
+B::Deparse now correctly handles try/catch blocks with more complex scopes.
+[L<GH #18874|https://github.com/Perl/perl5/issues/18874>]
+
+=back
+
+=head1 Obituary
+
+Raun "Spider" Boardman (SPIDB on CPAN), author of at least 66 commits to the
+Perl 5 core distribution between 1996 and 2002, passed away May 24 2021 from
+complications of COVID.  He will be missed.
+
+=head1 Acknowledgements
+
+Perl 5.35.1 represents approximately 4 weeks of development since Perl
+5.35.0 and contains approximately 57,000 lines of changes across 410 files
+from 28 authors.
+
+Excluding auto-generated files, documentation and release tools, there were
+approximately 53,000 lines of changes to 220 .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 5.35.1:
+
+Alyssa Ross, Chris 'BinGOs' Williams, Dan Book, Dan Jacobson, Dave Cross,
+Dave Lambley, E. Choroba, Felipe Gasper, H.Merijn Brand, Hugo van der
+Sanden, James E Keenan, Karen Etheridge, Karl Williamson, Leon Timmermans,
+Matthew Horsfall, Max Maischein, Michael G Schwern, Nicholas Clark, Paul
+Evans, Ricardo Signes, Richard Leach, Scott Baker, Thibault Duponchelle,
+Todd Rinaldo, Tomasz Konojacki, Tomoyuki Sadahiro, Tony Cook, Михаил
+Козачков.
+
+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<http://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
diff --git a/pod/perldelta.pod b/pod/perldelta.pod
index c20ff5f7ec..ca1ae4cf16 100644
--- a/pod/perldelta.pod
+++ b/pod/perldelta.pod
@@ -2,204 +2,408 @@
 
 =head1 NAME
 
-perldelta - what is new for perl v5.35.1
+[ 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 v5.35.2
 
 =head1 DESCRIPTION
 
-This document describes differences between the 5.35.0 release and the 5.35.1
+This document describes differences between the 5.35.1 release and the 5.35.2
 release.
 
-If you are upgrading from an earlier release such as 5.34.0, first read
-L<perl5350delta>, which describes differences between 5.34.0 and 5.35.0.
+If you are upgrading from an earlier release such as 5.35.0, first read
+L<perl5351delta>, which describes differences between 5.35.0 and 5.35.1.
 
-=head1 Modules and Pragmata
+=head1 Notice
 
-=head2 Updated Modules and Pragmata
+XXX Any important notices here
+
+=head1 Core Enhancements
+
+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.
+
+[ List each enhancement as a =head2 entry ]
+
+=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 1.56 to 1.57.
+XXX
 
-=item *
+=back
 
-L<Data::Dumper> has been upgraded from version 2.179 to 2.181.
+=head1 Modules and Pragmata
 
-=item *
+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.
 
-L<feature> has been upgraded from version 1.65 to 1.66.
+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.)
 
-=item *
+[ Within each section, list entries as an =item entry ]
 
-L<File::Copy> has been upgraded from version 2.35 to 2.36.
+=head2 New Modules and Pragmata
 
-Inode numbers are now compared as strings, so that large inode numbers
-are correctly distinguished. (GH #18788)
+=over 4
 
 =item *
 
-L<File::Glob> has been upgraded from version 1.33 to 1.35.
+XXX Remove this section if not applicable.
 
-=item *
+=back
 
-L<File::Spec> has been upgraded from version 3.80 to 3.81.
+=head2 Updated Modules and Pragmata
+
+=over 4
 
 =item *
 
-L<File::stat> has been upgraded from version 1.09 to 1.10.
+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.
+
+=back
 
-L<IO> has been upgraded from version 1.46 to 1.47.
+=head2 Removed Modules and Pragmata
 
-Implement sync() for win32.
+=over 4
 
 =item *
 
-L<Module::CoreList> has been upgraded from version 5.20210521 to 5.20210620.
+XXX
 
-=item *
+=back
 
-L<Opcode> has been upgraded from version 1.50 to 1.51.
+=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<open> has been upgraded from version 1.12 to 1.13.
+=head2 New Documentation
 
-=item *
+XXX Changes which create B<new> files in F<pod/> go here.
 
-L<PathTools|Cwd> has been upgraded from version 3.80 to 3.81.
+=head3 L<XXX>
 
-Inodes numbers are now compared as strings, so that large inode numbers
-are correctly distinguished. (GH #18788)
+XXX Description of the purpose of the new file here
 
-=item *
+=head2 Changes to Existing Documentation
 
-L<perlfaq> has been upgraded from version 5.20210411 to 5.20210520.
+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>.
 
-=item *
+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.
 
-L<POSIX> has been upgraded from version 1.97 to 1.98.
+Additionally, the following selected changes have been made:
 
-=item *
+=head3 L<XXX>
 
-L<Scalar::Util> has been upgraded from version 1.55 to 1.56.
+=over 4
 
 =item *
 
-L<Socket> has been upgraded from version 2.031 to 2.032.
+XXX Description of the change here
+
+=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>.
+
+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<Test::Simple> has been upgraded from version 1.302183 to 1.302185.
+XXX L<message|perldiag/"message">
+
+=back
+
+=head3 New Warnings
+
+=over 4
 
 =item *
 
-L<Unicode::Collate> has been upgraded from version 1.29 to 1.30.
+XXX L<message|perldiag/"message">
+
+=back
+
+=head2 Changes to Existing Diagnostics
+
+XXX Changes (i.e. rewording) of diagnostic messages go here
 
-One warning in F<mkheader> averted (rt.cpan.org #133952).
+=over 4
 
 =item *
 
-L<Unicode::UCD> has been upgraded from version 0.75 to 0.76.
+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 *
 
-L<version> has been upgraded from version 0.9928 to 0.9929.
+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 *
 
-L<XS::APItest> has been upgraded from version 1.16 to 1.17.
+XXX
 
 =back
 
-=head2 Changes to Existing Diagnostics
+=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.
+
+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 *
 
-L<Can't modify %s in %s|perldiag/"Can't modify %s in %s">
-(for scalar assignment to C<undef>)
+XXX
+
+=back
+
+=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 XXX-some-platform
 
-Attempting to perform a scalar assignment to C<undef>, for example via
-C<undef = $foo;>, previously triggered a fatal runtime error with the
-message "L<Modification of a read-only value attempted|perldiag/"Modification of a read-only value attempted">."
-It is more helpful to detect such attempted assignments prior to
-runtime, so they are now compile time errors, resulting in the message
-"Can't modify undef operator in scalar assignment".
+XXX
+
+=back
+
+=head2 Discontinued Platforms
+
+XXX List any platforms that this version of perl no longer compiles on.
+
+=over 4
+
+=item XXX-some-platform
+
+XXX
+
+=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 *
 
-Since the removal of PERL_OBJECT in Perl 5.8, PERL_IMPLICIT_CONTEXT and
-MULTIPLICITY have been synonymous and they were being used interchangeably.
-To simplify the code, all instances of PERL_IMPLICIT_CONTEXT have been
-replaced with MULTIPLICITY.
-
-PERL_IMPLICIT_CONTEXT will remain defined for compatibility with XS modules.
+XXX
 
 =back
 
 =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 *
 
-utime() now correctly sets errno/C<$!> when called on a closed handle.
+XXX
+
+=back
+
+=head1 Known Problems
+
+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.
+
+[ List each fix as an =item entry ]
+
+=over 4
 
 =item *
 
-B::Deparse now correctly handles try/catch blocks with more complex scopes.
-[L<GH #18874|https://github.com/Perl/perl5/issues/18874>]
+XXX
 
 =back
 
-=head1 Obituary
+=head1 Errata From Previous Releases
 
-Raun "Spider" Boardman (SPIDB on CPAN), author of at least 66 commits to the
-Perl 5 core distribution between 1996 and 2002, passed away May 24 2021 from
-complications of COVID.  He will be missed.
+=over 4
 
-=head1 Acknowledgements
+=item *
 
-Perl 5.35.1 represents approximately 4 weeks of development since Perl
-5.35.0 and contains approximately 57,000 lines of changes across 410 files
-from 28 authors.
+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 53,000 lines of changes to 220 .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 5.35.1:
+=head1 Obituary
 
-Alyssa Ross, Chris 'BinGOs' Williams, Dan Book, Dan Jacobson, Dave Cross,
-Dave Lambley, E. Choroba, Felipe Gasper, H.Merijn Brand, Hugo van der
-Sanden, James E Keenan, Karen Etheridge, Karl Williamson, Leon Timmermans,
-Matthew Horsfall, Max Maischein, Michael G Schwern, Nicholas Clark, Paul
-Evans, Ricardo Signes, Richard Leach, Scott Baker, Thibault Duponchelle,
-Todd Rinaldo, Tomasz Konojacki, Tomoyuki Sadahiro, Tony Cook, Михаил
-Козачков.
+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 v5.35.1..HEAD
 
 =head1 Reporting Bugs