add new perldelta for 5.35.10

10 files changed, 730 insertions, 281 deletions

diff --git a/MANIFEST b/MANIFEST
index a8b9cef874..ce3191f34a 100644
--- a/MANIFEST
+++ b/MANIFEST
@@ -5292,6 +5292,7 @@ pod/perl5355delta.pod		Perl changes in version 5.35.5
 pod/perl5356delta.pod		Perl changes in version 5.35.6
 pod/perl5357delta.pod		Perl changes in version 5.35.7
 pod/perl5358delta.pod		Perl changes in version 5.35.8
+pod/perl5359delta.pod		Perl changes in version 5.35.9
 pod/perl561delta.pod		Perl changes in version 5.6.1
 pod/perl56delta.pod		Perl changes in version 5.6
 pod/perl581delta.pod		Perl changes in version 5.8.1
diff --git a/Makefile.SH b/Makefile.SH
index 0eb39bdba4..0bc65f8896 100755
--- a/Makefile.SH
+++ b/Makefile.SH
@@ -613,7 +613,7 @@ esac
 
 $spitshell >>$Makefile <<'!NO!SUBS!'
 
-perltoc_pod_prereqs = extra.pods pod/perl5359delta.pod pod/perlapi.pod pod/perlintern.pod pod/perlmodlib.pod pod/perluniprops.pod
+perltoc_pod_prereqs = extra.pods pod/perl53510delta.pod pod/perlapi.pod pod/perlintern.pod pod/perlmodlib.pod pod/perluniprops.pod
 generated_pods = pod/perltoc.pod $(perltoc_pod_prereqs)
 generated_headers = uudmap.h bitcount.h mg_data.h
 
@@ -1129,9 +1129,9 @@ pod/perlintern.pod: $(MINIPERL_EXE) autodoc.pl embed.fnc
 pod/perlmodlib.pod: $(MINIPERL_EXE) pod/perlmodlib.PL MANIFEST
 	$(MINIPERL) pod/perlmodlib.PL -q
 
-pod/perl5359delta.pod: pod/perldelta.pod
-	$(RMS) pod/perl5359delta.pod
-	$(LNS) perldelta.pod pod/perl5359delta.pod
+pod/perl53510delta.pod: pod/perldelta.pod
+	$(RMS) pod/perl53510delta.pod
+	$(LNS) perldelta.pod pod/perl53510delta.pod
 
 extra.pods: $(MINIPERL_EXE)
 	-@test ! -f extra.pods || rm -f `cat extra.pods`
diff --git a/pod/.gitignore b/pod/.gitignore
index 4218ac045f..c2ceba51b9 100644
--- a/pod/.gitignore
+++ b/pod/.gitignore
@@ -48,7 +48,7 @@
 /roffitall
 
 # generated
-/perl5359delta.pod
+/perl53510delta.pod
 /perlapi.pod
 /perlintern.pod
 /perlmodlib.pod
diff --git a/pod/perl.pod b/pod/perl.pod
index c5b0c84eea..06470bd944 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
+    perl5359delta	Perl changes in version 5.35.9
     perl5358delta	Perl changes in version 5.35.8
     perl5357delta	Perl changes in version 5.35.7
     perl5356delta	Perl changes in version 5.35.6
diff --git a/pod/perl5359delta.pod b/pod/perl5359delta.pod
new file mode 100644
index 0000000000..9853494130
--- /dev/null
+++ b/pod/perl5359delta.pod
@@ -0,0 +1,460 @@
+=encoding utf8
+
+=head1 NAME
+
+perl5359delta - what is new for perl v5.35.9
+
+=head1 DESCRIPTION
+
+This document describes differences between the 5.35.8 release and the 5.35.9
+release.
+
+If you are upgrading from an earlier release such as 5.35.7, first read
+L<perl5358delta>, which describes differences between 5.35.7 and 5.35.8.
+
+=head1 Core Enhancements
+
+=head2 Subroutine signatures are no longer experimental
+
+Introduced in Perl version 5.20.0, and modified several times since, the
+subroutine signatures feature (C<use feature 'signatures'>) is now no longer
+considered experimental. It is now considered a stable language feature and
+is included in the C<:5.36> feature bundle, enabled automatically by
+C<use v5.36>, and no longer prints a warning.
+
+    use v5.36;
+
+    sub add ($x, $y) {
+      return $x + $y;
+    }
+
+Despite this, certain elements of signatured subroutines remain
+experimental; see below.
+
+=head2 @_ is now experimental within signatured subs
+
+Even though subroutine signatures are now stable, use of the default arguments
+array (C<@_>) with a subroutine that has a signature remains experimental,
+with its own warning category.  Silencing the C<experimental::signatures>
+warning category is not sufficient to dismiss this.  The new warning is
+emitted with the category name C<experimental::args_array_with_signatures>.
+
+Any subroutine that has a signature and tries to make use of the defaults
+argument array or an element thereof (C<@_> or C<$_[INDEX]>), either
+explicitly or implicitly (such as C<shift> or C<pop> with no argument) will
+provoke a warning at compile-time:
+
+    use v5.36;
+
+    sub f ($x, $y = 123) {
+      say "The first argument is $_[0]";
+    }
+
+Z<>
+
+    Use of @_ in array element with signatured subroutine is experimental
+    at file.pl line 4.
+
+The behaviour of code which attempts to do this is no longer specified, and
+may be subject to change in a future version.
+
+=head2 The C<isa> operator is no longer experimental
+
+Introduced in Perl version 5.32.0, this operator has remained unchanged
+since then. The operator is now considered a stable language feature and is
+included in the C<:5.36> feature bundle, enabled automatically by
+C<use v5.36>.
+
+For more detail see L<perlop/Class Instance Operator>.
+
+=head2 -g command-line flag
+
+A new command-line flag, -g, is available. It is a simpler alias for -0777.
+
+For more information, see L<perlrun/-g>.
+
+=head1 Deprecations
+
+=head2 Downgrading a C<use VERSION> statement to below v5.11
+
+Attempting to issue a second C<use VERSION> statement that requests a version
+lower than C<v5.11> when an earlier statement that requested a version at
+least C<v5.11> has already been seen, will now print a deprecation warning.
+
+For example:
+
+    use v5.14;
+    say "The say statement is permitted";
+    use v5.8;                               # This will print a warning
+    print "We must use print\n";
+
+This is because of an intended related change to the interaction between
+C<use VERSION> and C<use strict>. If you specify a version >= 5.11, strict is
+enabled implicitly. If you request a version < 5.11, strict will become
+disabled I<even if you had previously written> C<use strict>. This was not
+the previous behaviour of C<use VERSION>, which at present will track
+explicitly-enabled strictness flags independently.
+
+Code which wishes to mix versions in this manner should use lexical scoping
+with block syntax to ensure that the differently versioned regions remain
+lexically isolated.
+
+    {
+        use v5.14;
+        say "The say statement is permitted";
+    }
+    {
+        use v5.8;                           # No warning is emitted
+        print "We must use print\n";
+    }
+
+=head1 Modules and Pragmata
+
+=head2 Updated Modules and Pragmata
+
+=over 4
+
+=item *
+
+L<B::Deparse> has been upgraded from version 1.61 to 1.62.
+
+=item *
+
+L<charnames> has been upgraded from version 1.49 to 1.50.
+
+=item *
+
+L<CPAN> has been upgraded from version 2.29 to 2.33.
+
+=item *
+
+L<Devel::PPPort> has been upgraded from version 3.63 to 3.64.
+
+=item *
+
+L<experimental> has been upgraded from version 0.025 to 0.027.
+
+=item *
+
+L<feature> has been upgraded from version 1.69 to 1.70.
+
+=item *
+
+L<File::Copy> has been upgraded from version 2.38 to 2.39.
+
+=item *
+
+L<Hash::Util> has been upgraded from version 0.27 to 0.28.
+
+=item *
+
+L<Hash::Util::FieldHash> has been upgraded from version 1.25 to 1.26.
+
+=item *
+
+L<Module::CoreList> has been upgraded from version 5.20220120 to 5.20220220.
+
+=item *
+
+L<Opcode> has been upgraded from version 1.55 to 1.56.
+
+=item *
+
+L<overload> has been upgraded from version 1.34 to 1.35.
+
+=item *
+
+L<re> has been upgraded from version 0.41 to 0.42.
+
+=item *
+
+L<Scalar::Util> has been upgraded from version 1.60 to 1.61.
+
+=item *
+
+L<sigtrap> has been upgraded from version 1.09 to 1.10.
+
+=item *
+
+L<Tie::SubstrHash> has been upgraded from version 1.00 to 1.01.
+
+=item *
+
+L<warnings> has been upgraded from version 1.56 to 1.57.
+
+=item *
+
+L<XS::APItest> has been upgraded from version 1.20 to 1.21.
+
+=back
+
+=head1 Diagnostics
+
+=head2 New Diagnostics
+
+=head3 New Warnings
+
+=over 4
+
+=item *
+
+L<Built-in function '%s' is experimental|perldiag/"Built-in function '%s' is experimental">
+
+A call is being made to a function in the
+C<builtin::> namespace, which is currently experimental.
+
+=item *
+
+L<Implicit use of @_ in %s with signatured subroutine is experimental|perldiag/"Implicit use of @_ in %s with signatured subroutine is experimental">
+
+An expression that implicitly involves the C<@_> arguments array was found in
+a subroutine that uses a signature.
+
+=item *
+
+L<Use of @_ in %s with signatured subroutine is experimental|perldiag/"Use of @_ in %s with signatured subroutine is experimental">
+
+An expression involving the C<@_> arguments array was found in a subroutine that uses a signature.
+
+=item *
+
+L<Downgrading a use VERSION declaration to below v5.11 is deprecated|perldiag/"Downgrading a use VERSION declaration to below v5.11 is deprecated">
+
+This warning is emitted on a C<use VERSION> statement that
+requests a version below v5.11 (when the effects of C<use strict> would be
+disabled), after a previous declaration of one having a larger number (which
+would have enabled these effects)
+
+=back
+
+=head2 Changes to Existing Diagnostics
+
+=over 4
+
+=item *
+
+L<Subroutine %s redefined|perldiag/"Subroutine %s redefined">
+
+Localized subroutine redefinitions no longer trigger this warning.
+
+=back
+
+=head1 Internal Changes
+
+=over 4
+
+=item *
+
+New equality-test functions C<sv_numeq> and C<sv_streq> have been added, along
+with C<..._flags>-suffixed variants.  These expose a simple and consistent API
+to perform numerical or string comparison which is aware of operator
+overloading.
+
+=item *
+
+Reading the string form of an integer value no longer sets the flag C<SVf_POK>.
+The string form is still cached internally, and still re-read directly by the
+macros C<SvPV(sv)> I<etc> (inline, without calling a C function). XS code that
+already calls the APIs to get values will not be affected by this change. XS
+code that accesses flags directly instead of using API calls to express its
+intent I<might> break, but such code likely is already buggy if passed some
+other values, such as floating point values or objects with string overloading.
+
+This small change permits code (such as JSON serializers) to reliably determine
+between
+
+=over 4
+
+=item *
+
+a value that was initially B<written> as an integer, but then B<read> as a string
+
+    my $answer = 42;
+    print "The answer is $answer\n";
+
+=item *
+
+that same value that was initially B<written> as a string, but then B<read> as an integer
+
+    my $answer = "42";
+    print "That doesn't look right\n"
+        unless $answer == 6 * 9;
+
+=back
+
+For the first case (originally written as an integer), we now have:
+
+    use Devel::Peek;
+    my $answer = 42;
+    Dump ($answer);
+    my $void = "$answer";
+    print STDERR "\n";
+    Dump($answer)
+
+
+    SV = IV(0x562538925778) at 0x562538925788
+      REFCNT = 1
+      FLAGS = (IOK,pIOK)
+      IV = 42
+
+    SV = PVIV(0x5625389263c0) at 0x562538925788
+      REFCNT = 1
+      FLAGS = (IOK,pIOK,pPOK)
+      IV = 42
+      PV = 0x562538919b50 "42"\0
+      CUR = 2
+      LEN = 10
+
+For the second (originally written as a string), we now have:
+
+    use Devel::Peek;
+    my $answer = "42";
+    Dump ($answer);
+    my $void = $answer == 6 * 9;
+    print STDERR "\n";
+    Dump($answer)'
+
+
+    SV = PV(0x5586ffe9bfb0) at 0x5586ffec0788
+      REFCNT = 1
+      FLAGS = (POK,IsCOW,pPOK)
+      PV = 0x5586ffee7fd0 "42"\0
+      CUR = 2
+      LEN = 10
+      COW_REFCNT = 1
+
+    SV = PVIV(0x5586ffec13c0) at 0x5586ffec0788
+      REFCNT = 1
+      FLAGS = (IOK,POK,IsCOW,pIOK,pPOK)
+      IV = 42
+      PV = 0x5586ffee7fd0 "42"\0
+      CUR = 2
+      LEN = 10
+      COW_REFCNT = 1
+
+(One can't rely on the presence or absence of the flag C<SVf_IsCOW> to
+determine the history of operations on a scalar.)
+
+Previously both cases would be indistinguishable, with all 4 flags set:
+
+    SV = PVIV(0x55d4d62edaf0) at 0x55d4d62f0930
+      REFCNT = 1
+      FLAGS = (IOK,POK,pIOK,pPOK)
+      IV = 42
+      PV = 0x55d4d62e1740 "42"\0
+      CUR = 2
+      LEN = 10
+
+(and possibly C<SVf_IsCOW>, but not always)
+
+This now means that if XS code I<really> needs to determine which form a value
+was first written as, it should implement logic roughly
+
+    if (flags & SVf_IOK|SVf_NOK) && !(flags & SVf_POK)
+        serialize as number
+    else if (flags & SVf_POK)
+        serialize as string
+    else
+        the existing guesswork ...
+
+Note that this doesn't cover "dualvars" - scalars that report different
+values when asked for their string form or number form (such as C<$!>).
+Most serialization formats cannot represent such duplicity.
+
+I<The existing guesswork> remains because as well as dualvars, values might
+be C<undef>, references, overloaded references, typeglobs and other things that
+Perl itself can represent but do not map one-to-one into external formats, so
+need some amount of approximation or encapsulation.
+
+=item *
+
+Memory for hash iterator state (C<struct xpvhv_aux>) is now allocated as part
+of the hash body, instead of as part of the block of memory allocated for the
+main hash array.
+
+Nothing else changes - memory for this structure is still allocated only when
+needed, is still accessed via the C<HvAUX()> macro, and the macro should only
+be called when C<SvOOK()> is true. Hashes are still always of type C<SVt_PVHV>,
+hash bodies are still allocated from arenas, and the address of the hash
+doesn't change, because the address is the pointer to the head structure, which
+never moves.
+
+Internally, a second arena (the arena with index 1) is used to allocate larger
+bodies with space for C<struct xpvhv_aux>, the body "upgraded", and the "head"
+structure updated to reflect this (much the same way that the bodies of scalars
+are upgraded). We already re-purpose arenas - arena with index 0 is used for
+C<HE *>s.
+
+None of this affects documented public XS interfaces. The only code changes are
+in F<hv.c> and F<sv.c>. As the rest of the core itself uses these macros but
+needed no changes, likely no code on CPAN will be affected either.
+
+=back
+
+=head1 Acknowledgements
+
+Perl 5.35.9 represents approximately 4 weeks of development since Perl
+5.35.8 and contains approximately 8,700 lines of changes across 280 files
+from 22 authors.
+
+Excluding auto-generated files, documentation and release tools, there were
+approximately 3,000 lines of changes to 110 .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 5.35.9:
+
+Branislav Zahradník, Christopher Yeleighton, Dagfinn Ilmari Mannsåker,
+Dave Cross, David Cantrell, Hugo van der Sanden, James E Keenan, James
+Raspass, Karl Williamson, Leon Timmermans, Max Maischein, Michiel Beijen,
+Nicholas Clark, Nicolas R., Paul Evans, Renee Baecker, Ricardo Signes,
+Sergey Zhmylove, TAKAI Kousuke, Tomasz Konojacki, Tony Cook, Yves Orton.
+
+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 6367d3507e..5951c037f2 100644
--- a/pod/perldelta.pod
+++ b/pod/perldelta.pod
@@ -2,425 +2,408 @@
 
 =head1 NAME
 
-perldelta - what is new for perl v5.35.9
+[ 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 v5.35.10
 
 =head1 DESCRIPTION
 
-This document describes differences between the 5.35.8 release and the 5.35.9
+This document describes differences between the 5.35.9 release and the 5.35.10
 release.
 
-If you are upgrading from an earlier release such as 5.35.7, first read
-L<perl5358delta>, which describes differences between 5.35.7 and 5.35.8.
+If you are upgrading from an earlier release such as 5.35.8, first read
+L<perl5359delta>, which describes differences between 5.35.8 and 5.35.9.
+
+=head1 Notice
+
+XXX Any important notices here
 
 =head1 Core Enhancements
 
-=head2 Subroutine signatures are no longer experimental
+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.
 
-Introduced in Perl version 5.20.0, and modified several times since, the
-subroutine signatures feature (C<use feature 'signatures'>) is now no longer
-considered experimental. It is now considered a stable language feature and
-is included in the C<:5.36> feature bundle, enabled automatically by
-C<use v5.36>, and no longer prints a warning.
+[ List each enhancement as a =head2 entry ]
 
-    use v5.36;
+=head1 Security
 
-    sub add ($x, $y) {
-      return $x + $y;
-    }
+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.
 
-Despite this, certain elements of signatured subroutines remain
-experimental; see below.
+[ List each security issue as a =head2 entry ]
 
-=head2 @_ is now experimental within signatured subs
+=head1 Incompatible Changes
 
-Even though subroutine signatures are now stable, use of the default arguments
-array (C<@_>) with a subroutine that has a signature remains experimental,
-with its own warning category.  Silencing the C<experimental::signatures>
-warning category is not sufficient to dismiss this.  The new warning is
-emitted with the category name C<experimental::args_array_with_signatures>.
+XXX For a release on a stable branch, this section aspires to be:
 
-Any subroutine that has a signature and tries to make use of the defaults
-argument array or an element thereof (C<@_> or C<$_[INDEX]>), either
-explicitly or implicitly (such as C<shift> or C<pop> with no argument) will
-provoke a warning at compile-time:
+    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.
 
-    use v5.36;
+[ List each incompatible change as a =head2 entry ]
 
-    sub f ($x, $y = 123) {
-      say "The first argument is $_[0]";
-    }
+=head1 Deprecations
 
-Z<>
+XXX Any deprecated features, syntax, modules etc. should be listed here.
 
-    Use of @_ in array element with signatured subroutine is experimental
-    at file.pl line 4.
+=head2 Module removals
 
-The behaviour of code which attempts to do this is no longer specified, and
-may be subject to change in a future version.
+XXX Remove this section if not applicable.
 
-=head2 The C<isa> operator is no longer experimental
+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.
 
-Introduced in Perl version 5.32.0, this operator has remained unchanged
-since then. The operator is now considered a stable language feature and is
-included in the C<:5.36> feature bundle, enabled automatically by
-C<use v5.36>.
+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.
 
-For more detail see L<perlop/Class Instance Operator>.
+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.
 
-=head2 -g command-line flag
+=over
 
-A new command-line flag, -g, is available. It is a simpler alias for -0777.
+=item XXX
 
-For more information, see L<perlrun/-g>.
+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.
 
-=head1 Deprecations
+=back
+
+[ List each other deprecation as a =head2 entry ]
 
-=head2 Downgrading a C<use VERSION> statement to below v5.11
+=head1 Performance Enhancements
 
-Attempting to issue a second C<use VERSION> statement that requests a version
-lower than C<v5.11> when an earlier statement that requested a version at
-least C<v5.11> has already been seen, will now print a deprecation warning.
+XXX Changes which enhance performance without changing behaviour go here.
+There may well be none in a stable release.
 
-For example:
+[ List each enhancement as an =item entry ]
 
-    use v5.14;
-    say "The say statement is permitted";
-    use v5.8;                               # This will print a warning
-    print "We must use print\n";
+=over 4
 
-This is because of an intended related change to the interaction between
-C<use VERSION> and C<use strict>. If you specify a version >= 5.11, strict is
-enabled implicitly. If you request a version < 5.11, strict will become
-disabled I<even if you had previously written> C<use strict>. This was not
-the previous behaviour of C<use VERSION>, which at present will track
-explicitly-enabled strictness flags independently.
+=item *
 
-Code which wishes to mix versions in this manner should use lexical scoping
-with block syntax to ensure that the differently versioned regions remain
-lexically isolated.
+XXX
 
-    {
-        use v5.14;
-        say "The say statement is permitted";
-    }
-    {
-        use v5.8;                           # No warning is emitted
-        print "We must use print\n";
-    }
+=back
 
 =head1 Modules and Pragmata
 
-=head2 Updated Modules and Pragmata
+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.
+
+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.)
+
+[ Within each section, list entries as an =item entry ]
+
+=head2 New Modules and Pragmata
 
 =over 4
 
 =item *
 
-L<B::Deparse> has been upgraded from version 1.61 to 1.62.
+XXX Remove this section if not applicable.
 
-=item *
+=back
 
-L<charnames> has been upgraded from version 1.49 to 1.50.
+=head2 Updated Modules and Pragmata
+
+=over 4
 
 =item *
 
-L<CPAN> has been upgraded from version 2.29 to 2.33.
+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<Devel::PPPort> has been upgraded from version 3.63 to 3.64.
+=back
 
-=item *
+=head2 Removed Modules and Pragmata
 
-L<experimental> has been upgraded from version 0.025 to 0.027.
+=over 4
 
 =item *
 
-L<feature> has been upgraded from version 1.69 to 1.70.
+XXX
 
-=item *
+=back
 
-L<File::Copy> has been upgraded from version 2.38 to 2.39.
+=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<Hash::Util> has been upgraded from version 0.27 to 0.28.
+=head2 New Documentation
 
-=item *
+XXX Changes which create B<new> files in F<pod/> go here.
 
-L<Hash::Util::FieldHash> has been upgraded from version 1.25 to 1.26.
+=head3 L<XXX>
 
-=item *
+XXX Description of the purpose of the new file here
 
-L<Module::CoreList> has been upgraded from version 5.20220120 to 5.20220220.
+=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>.
 
-L<Opcode> has been upgraded from version 1.55 to 1.56.
+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.
 
-=item *
+Additionally, the following selected changes have been made:
 
-L<overload> has been upgraded from version 1.34 to 1.35.
+=head3 L<XXX>
+
+=over 4
 
 =item *
 
-L<re> has been upgraded from version 0.41 to 0.42.
+XXX Description of the change here
 
-=item *
+=back
+
+=head1 Diagnostics
 
-L<Scalar::Util> has been upgraded from version 1.60 to 1.61.
+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>.
 
-=item *
+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
 
-L<sigtrap> has been upgraded from version 1.09 to 1.10.
+XXX Newly added diagnostic messages go under here, separated into New Errors
+and New Warnings
+
+=head3 New Errors
+
+=over 4
 
 =item *
 
-L<Tie::SubstrHash> has been upgraded from version 1.00 to 1.01.
+XXX L<message|perldiag/"message">
+
+=back
+
+=head3 New Warnings
+
+=over 4
 
 =item *
 
-L<warnings> has been upgraded from version 1.56 to 1.57.
+XXX L<message|perldiag/"message">
+
+=back
+
+=head2 Changes to Existing Diagnostics
+
+XXX Changes (i.e. rewording) of diagnostic messages go here
+
+=over 4
 
 =item *
 
-L<XS::APItest> has been upgraded from version 1.20 to 1.21.
+XXX Describe change here
 
 =back
 
-=head1 Diagnostics
+=head1 Utility Changes
 
-=head2 New Diagnostics
+XXX Changes to installed programs such as F<perldoc> and F<xsubpp> go here.
+Most of these are built within the directory F<utils>.
 
-=head3 New Warnings
+[ 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<Built-in function '%s' is experimental|perldiag/"Built-in function '%s' is experimental">
+XXX
 
-A call is being made to a function in the
-C<builtin::> namespace, which is currently experimental.
+=back
 
-=item *
+=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.
 
-L<Implicit use of @_ in %s with signatured subroutine is experimental|perldiag/"Implicit use of @_ in %s with signatured subroutine is experimental">
+[ List changes as an =item entry ].
 
-An expression that implicitly involves the C<@_> arguments array was found in
-a subroutine that uses a signature.
+=over 4
 
 =item *
 
-L<Use of @_ in %s with signatured subroutine is experimental|perldiag/"Use of @_ in %s with signatured subroutine is experimental">
+XXX
 
-An expression involving the C<@_> arguments array was found in a subroutine that uses a signature.
+=back
 
-=item *
+=head1 Testing
 
-L<Downgrading a use VERSION declaration to below v5.11 is deprecated|perldiag/"Downgrading a use VERSION declaration to below v5.11 is deprecated">
+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.
 
-This warning is emitted on a C<use VERSION> statement that
-requests a version below v5.11 (when the effects of C<use strict> would be
-disabled), after a previous declaration of one having a larger number (which
-would have enabled these effects)
+XXX If there were no significant test changes, say this:
 
-=back
+Tests were added and changed to reflect the other additions and changes
+in this release.
 
-=head2 Changes to Existing Diagnostics
+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<Subroutine %s redefined|perldiag/"Subroutine %s redefined">
+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
 
-Localized subroutine redefinitions no longer trigger this warning.
+XXX
 
 =back
 
-=head1 Internal Changes
+=head2 Discontinued Platforms
+
+XXX List any platforms that this version of perl no longer compiles on.
 
 =over 4
 
-=item *
+=item XXX-some-platform
 
-New equality-test functions C<sv_numeq> and C<sv_streq> have been added, along
-with C<..._flags>-suffixed variants.  These expose a simple and consistent API
-to perform numerical or string comparison which is aware of operator
-overloading.
+XXX
 
-=item *
+=back
 
-Reading the string form of an integer value no longer sets the flag C<SVf_POK>.
-The string form is still cached internally, and still re-read directly by the
-macros C<SvPV(sv)> I<etc> (inline, without calling a C function). XS code that
-already calls the APIs to get values will not be affected by this change. XS
-code that accesses flags directly instead of using API calls to express its
-intent I<might> break, but such code likely is already buggy if passed some
-other values, such as floating point values or objects with string overloading.
+=head2 Platform-Specific Notes
 
-This small change permits code (such as JSON serializers) to reliably determine
-between
+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 *
+=item XXX-some-platform
 
-a value that was initially B<written> as an integer, but then B<read> as a string
+XXX
 
-    my $answer = 42;
-    print "The answer is $answer\n";
+=back
 
-=item *
+=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
 
-that same value that was initially B<written> as a string, but then B<read> as an integer
+=item *
 
-    my $answer = "42";
-    print "That doesn't look right\n"
-        unless $answer == 6 * 9;
+XXX
 
 =back
 
-For the first case (originally written as an integer), we now have:
-
-    use Devel::Peek;
-    my $answer = 42;
-    Dump ($answer);
-    my $void = "$answer";
-    print STDERR "\n";
-    Dump($answer)
-
-
-    SV = IV(0x562538925778) at 0x562538925788
-      REFCNT = 1
-      FLAGS = (IOK,pIOK)
-      IV = 42
-
-    SV = PVIV(0x5625389263c0) at 0x562538925788
-      REFCNT = 1
-      FLAGS = (IOK,pIOK,pPOK)
-      IV = 42
-      PV = 0x562538919b50 "42"\0
-      CUR = 2
-      LEN = 10
-
-For the second (originally written as a string), we now have:
-
-    use Devel::Peek;
-    my $answer = "42";
-    Dump ($answer);
-    my $void = $answer == 6 * 9;
-    print STDERR "\n";
-    Dump($answer)'
-
-
-    SV = PV(0x5586ffe9bfb0) at 0x5586ffec0788
-      REFCNT = 1
-      FLAGS = (POK,IsCOW,pPOK)
-      PV = 0x5586ffee7fd0 "42"\0
-      CUR = 2
-      LEN = 10
-      COW_REFCNT = 1
-
-    SV = PVIV(0x5586ffec13c0) at 0x5586ffec0788
-      REFCNT = 1
-      FLAGS = (IOK,POK,IsCOW,pIOK,pPOK)
-      IV = 42
-      PV = 0x5586ffee7fd0 "42"\0
-      CUR = 2
-      LEN = 10
-      COW_REFCNT = 1
-
-(One can't rely on the presence or absence of the flag C<SVf_IsCOW> to
-determine the history of operations on a scalar.)
-
-Previously both cases would be indistinguishable, with all 4 flags set:
-
-    SV = PVIV(0x55d4d62edaf0) at 0x55d4d62f0930
-      REFCNT = 1
-      FLAGS = (IOK,POK,pIOK,pPOK)
-      IV = 42
-      PV = 0x55d4d62e1740 "42"\0
-      CUR = 2
-      LEN = 10
-
-(and possibly C<SVf_IsCOW>, but not always)
-
-This now means that if XS code I<really> needs to determine which form a value
-was first written as, it should implement logic roughly
-
-    if (flags & SVf_IOK|SVf_NOK) && !(flags & SVf_POK)
-        serialize as number
-    else if (flags & SVf_POK)
-        serialize as string
-    else
-        the existing guesswork ...
-
-Note that this doesn't cover "dualvars" - scalars that report different
-values when asked for their string form or number form (such as C<$!>).
-Most serialization formats cannot represent such duplicity.
-
-I<The existing guesswork> remains because as well as dualvars, values might
-be C<undef>, references, overloaded references, typeglobs and other things that
-Perl itself can represent but do not map one-to-one into external formats, so
-need some amount of approximation or encapsulation.
+=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 *
 
-Memory for hash iterator state (C<struct xpvhv_aux>) is now allocated as part
-of the hash body, instead of as part of the block of memory allocated for the
-main hash array.
+XXX
 
-Nothing else changes - memory for this structure is still allocated only when
-needed, is still accessed via the C<HvAUX()> macro, and the macro should only
-be called when C<SvOOK()> is true. Hashes are still always of type C<SVt_PVHV>,
-hash bodies are still allocated from arenas, and the address of the hash
-doesn't change, because the address is the pointer to the head structure, which
-never moves.
+=back
 
-Internally, a second arena (the arena with index 1) is used to allocate larger
-bodies with space for C<struct xpvhv_aux>, the body "upgraded", and the "head"
-structure updated to reflect this (much the same way that the bodies of scalars
-are upgraded). We already re-purpose arenas - arena with index 0 is used for
-C<HE *>s.
+=head1 Known Problems
 
-None of this affects documented public XS interfaces. The only code changes are
-in F<hv.c> and F<sv.c>. As the rest of the core itself uses these macros but
-needed no changes, likely no code on CPAN will be affected either.
+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 *
+
+XXX
 
 =back
 
-=head1 Acknowledgements
+=head1 Errata From Previous Releases
 
-Perl 5.35.9 represents approximately 4 weeks of development since Perl
-5.35.8 and contains approximately 8,700 lines of changes across 280 files
-from 22 authors.
+=over 4
+
+=item *
 
-Excluding auto-generated files, documentation and release tools, there were
-approximately 3,000 lines of changes to 110 .pm, .t, .c and .h files.
+XXX Add anything here that we forgot to add, or were mistaken about, in
+the perldelta of a previous release.
 
-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 5.35.9:
+=back
+
+=head1 Obituary
 
-Branislav Zahradník, Christopher Yeleighton, Dagfinn Ilmari Mannsåker,
-Dave Cross, David Cantrell, Hugo van der Sanden, James E Keenan, James
-Raspass, Karl Williamson, Leon Timmermans, Max Maischein, Michiel Beijen,
-Nicholas Clark, Nicolas R., Paul Evans, Renee Baecker, Ricardo Signes,
-Sergey Zhmylove, TAKAI Kousuke, Tomasz Konojacki, Tony Cook, Yves Orton.
+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 v5.35.9..HEAD
 
 =head1 Reporting Bugs
 
diff --git a/vms/descrip_mms.template b/vms/descrip_mms.template
index 2812c5a160..91d8fa5623 100644
--- a/vms/descrip_mms.template
+++ b/vms/descrip_mms.template
@@ -313,7 +313,7 @@ utils : $(utils1) $(utils2) $(utils3) $(utils4) $(utils5)
 extra.pods : miniperl
 	@ @extra_pods.com
 
-PERLDELTA_CURRENT = [.pod]perl5359delta.pod
+PERLDELTA_CURRENT = [.pod]perl53510delta.pod
 
 $(PERLDELTA_CURRENT) : [.pod]perldelta.pod
 	Copy/NoConfirm/Log $(MMS$SOURCE) $(PERLDELTA_CURRENT)
diff --git a/win32/GNUmakefile b/win32/GNUmakefile
index c231d4e299..cce0eb7e17 100644
--- a/win32/GNUmakefile
+++ b/win32/GNUmakefile
@@ -1625,7 +1625,7 @@ utils: $(HAVEMINIPERL) ..\utils\Makefile
 	copy ..\README.tw       ..\pod\perltw.pod
 	copy ..\README.vos      ..\pod\perlvos.pod
 	copy ..\README.win32    ..\pod\perlwin32.pod
-	copy ..\pod\perldelta.pod ..\pod\perl5359delta.pod
+	copy ..\pod\perldelta.pod ..\pod\perl53510delta.pod
 	$(MINIPERL) -I..\lib $(PL2BAT) $(UTILS)
 	$(MINIPERL) -I..\lib ..\autodoc.pl ..
 	$(MINIPERL) -I..\lib ..\pod\perlmodlib.PL -q ..
@@ -1724,7 +1724,7 @@ distclean: realclean
 	-if exist $(LIBDIR)\Win32API rmdir /s /q $(LIBDIR)\Win32API
 	-if exist $(LIBDIR)\XS rmdir /s /q $(LIBDIR)\XS
 	-cd $(PODDIR) && del /f *.html *.bat roffitall \
-	    perl5359delta.pod perlaix.pod perlamiga.pod perlandroid.pod \
+	    perl53510delta.pod perlaix.pod perlamiga.pod perlandroid.pod \
 	    perlapi.pod perlbs2000.pod perlcn.pod perlcygwin.pod \
 	    perlfreebsd.pod perlhaiku.pod perlhpux.pod perlhurd.pod \
 	    perlintern.pod perlirix.pod perljp.pod perlko.pod perllinux.pod \
diff --git a/win32/Makefile b/win32/Makefile
index b38fde1903..812d5b5414 100644
--- a/win32/Makefile
+++ b/win32/Makefile
@@ -1151,7 +1151,7 @@ utils: $(PERLEXE) ..\utils\Makefile
 	copy ..\README.tw       ..\pod\perltw.pod
 	copy ..\README.vos      ..\pod\perlvos.pod
 	copy ..\README.win32    ..\pod\perlwin32.pod
-	copy ..\pod\perldelta.pod ..\pod\perl5359delta.pod
+	copy ..\pod\perldelta.pod ..\pod\perl53510delta.pod
 	cd ..\win32
 	$(PERLEXE) $(PL2BAT) $(UTILS)
 	$(MINIPERL) -I..\lib ..\autodoc.pl ..
@@ -1251,7 +1251,7 @@ distclean: realclean
 	-if exist $(LIBDIR)\Win32API rmdir /s /q $(LIBDIR)\Win32API
 	-if exist $(LIBDIR)\XS rmdir /s /q $(LIBDIR)\XS
 	-cd $(PODDIR) && del /f *.html *.bat roffitall \
-	    perl5359delta.pod perlaix.pod perlamiga.pod perlandroid.pod \
+	    perl53510delta.pod perlaix.pod perlamiga.pod perlandroid.pod \
 	    perlapi.pod perlbs2000.pod perlcn.pod perlcygwin.pod \
 	    perlfreebsd.pod perlhaiku.pod perlhpux.pod perlhurd.pod \
 	    perlintern.pod perlirix.pod perljp.pod perlko.pod perllinux.pod \
diff --git a/win32/pod.mak b/win32/pod.mak
index a7a2e7abd2..5d78e79eac 100644
--- a/win32/pod.mak
+++ b/win32/pod.mak
@@ -66,6 +66,7 @@ POD = perl.pod	\
 	perl5321delta.pod	\
 	perl5340delta.pod	\
 	perl5350delta.pod	\
+	perl53510delta.pod	\
 	perl5351delta.pod	\
 	perl5352delta.pod	\
 	perl5353delta.pod	\
@@ -239,6 +240,7 @@ MAN = perl.man	\
 	perl5321delta.man	\
 	perl5340delta.man	\
 	perl5350delta.man	\
+	perl53510delta.man	\
 	perl5351delta.man	\
 	perl5352delta.man	\
 	perl5353delta.man	\
@@ -412,6 +414,7 @@ HTML = perl.html	\
 	perl5321delta.html	\
 	perl5340delta.html	\
 	perl5350delta.html	\
+	perl53510delta.html	\
 	perl5351delta.html	\
 	perl5352delta.html	\
 	perl5353delta.html	\
@@ -585,6 +588,7 @@ TEX = perl.tex	\
 	perl5321delta.tex	\
 	perl5340delta.tex	\
 	perl5350delta.tex	\
+	perl53510delta.tex	\
 	perl5351delta.tex	\
 	perl5352delta.tex	\
 	perl5353delta.tex	\