add new perldelta for 5.21.1

1 files changed, 339 insertions, 22 deletions

diff --git a/pod/perldelta.pod b/pod/perldelta.pod
index 175554e134..6b839f674e 100644
--- a/pod/perldelta.pod
+++ b/pod/perldelta.pod
@@ -2,26 +2,124 @@
 
 =head1 NAME
 
-perldelta - what is new for perl v5.21.0
+[ 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 v5.21.1
 
 =head1 DESCRIPTION
 
-This document describes differences between the 5.21.0 release and the 5.20.0
+This document describes differences between the 5.21.0 release and the 5.21.1
 release.
 
+If you are upgrading from an earlier release such as 5.20.0, first read
+L<perl5210delta>, which describes differences between 5.20.0 and 5.21.0.
+
+=head1 Notice
+
+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 inapplicable.
+
+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 a =item entry ]
+
+=over 4
+
+=item *
+
+XXX
+
+=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.
+
+[ Within each section, list entries as a =item entry ]
+
+=head2 New Modules and Pragmata
 
 =over 4
 
 =item *
 
-L<feature> has been upgraded from version 1.36 to 1.37.
+XXX
+
+=back
+
+=head2 Updated Modules and Pragmata
+
+=over 4
 
 =item *
 
-L<Module::CoreList> has been upgraded from version 3.10 to 5.021001.
+L<XXX> has been upgraded from version A.xx to B.yy.
 
 =back
 
@@ -31,37 +129,256 @@ L<Module::CoreList> has been upgraded from version 3.10 to 5.021001.
 
 =item *
 
-L<CGI> has been removed from the core.  It is still available on the CPAN.
+XXX
+
+=back
+
+=head1 Documentation
+
+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>.
+
+=head2 New Documentation
+
+XXX Changes which create B<new> files in F<pod/> go here.
+
+=head3 L<XXX>
+
+XXX Description of the purpose of the new file here
+
+=head2 Changes to Existing Documentation
+
+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.
+
+=head3 L<XXX>
+
+=over 4
 
 =item *
 
-L<Module::Build> has been removed from the core.  It is still available on the
-CPAN.
+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<Package::Constants> has been removed from the core.  It is still available on
-the CPAN.
+XXX L<message|perldiag/"message">
 
 =back
 
-=head1 Acknowledgements
+=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<perlbug> and F<xsubpp> go here.
+Most of these are built within the directories F<utils> and F<x2p>.
+
+[ 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 a =item entry ].
+
+=over 4
+
+=item *
+
+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.
+
+[ List each test improvement as a =item entry ]
+
+=over 4
+
+=item *
+
+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 a =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
+
+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
 
-Perl 5.21.0 represents approximately 12 hours of development since Perl 5.20.0
-and contains approximately 44,000 lines of changes across 190 files from 1
-author.
+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.
 
-Excluding auto-generated files, documentation and release tools, there were
-approximately 33,000 lines of changes to 140 .pm, .t, .c and .h files.
+=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 a =item entry ]
+
+=over 4
+
+=item *
+
+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 a =item entry ]
+
+=over 4
+
+=item *
+
+XXX
 
-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 5.21.0:
+=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 a =item entry ]
+
+=over 4
+
+=item *
+
+XXX
+
+=back
+
+=head1 Errata From Previous Releases
+
+=over 4
+
+=item *
+
+XXX Add anything here that we forgot to add, or were mistaken about, in
+the perldelta of a previous release.
+
+=back
+
+=head1 Obituary
+
+XXX If any significant core contributor has died, we've added a short obituary
+here.
+
+=head1 Acknowledgements
 
-Nicholas Clark, Ricardo Signes.
+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 v5.21.1..HEAD
 
 =head1 Reporting Bugs