first run through for the perldelta, more to come

1 files changed, 133 insertions, 215 deletions

diff --git a/pod/perldelta.pod b/pod/perldelta.pod
index 0a697d3ed5..023c1f2288 100644
--- a/pod/perldelta.pod
+++ b/pod/perldelta.pod
@@ -2,9 +2,6 @@
 
 =head1 NAME
 
-[ 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 v5.23.7
 
 =head1 DESCRIPTION
@@ -15,18 +12,8 @@ release.
 If you are upgrading from an earlier release such as 5.23.5, first read
 L<perl5236delta>, which describes differences between 5.23.5 and 5.23.6.
 
-=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 ]
-
 =head2 New C<\b{lb}> boundary in regular expressions
 
 C<lb> stands for Line Break.  It is a Unicode property
@@ -48,15 +35,12 @@ L<[perl #126755]|https://rt.perl.org/Ticket/Display.html?id=126755>
 This is CVE-2015-8607.  For more information see
 L<[perl #126862]|https://rt.perl.org/Ticket/Display.html?id=126862>
 
-=head1 Incompatible Changes
-
-XXX For a release on a stable branch, this section aspires to be:
+=head2 Avoid accessing uninitialized memory in win32 C<crypt()>
 
-    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.
+Added validation that will detect both a short salt and invalid characters
+in the salt.  L<[perl #126922]|https://rt.perl.org/Ticket/Display.html?id=126922>
 
-[ List each incompatible change as a =head2 entry ]
+=head1 Incompatible Changes
 
 =head2 C<qr/\b{wb}/> is now tailored to Perl expectations
 
@@ -69,51 +53,13 @@ L<perlrebackslash/\b{wb}>
 
 =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
+=head2 C<*glob{FILEHANDLE}> is no longer deprecated
 
-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
+We are now trying to use deprecation warnings only when we believe
+that a behavior will really be removed or made an error.  Since we
+don't plan to do that with C<*glob{FILEHANDLE}>, the warning is not
+useful and may be harmful.
+L<[perl #127060]|https://rt.perl.org/Ticket/Display.html?id=127060>
 
 =head1 Modules and Pragmata
 
@@ -123,18 +69,6 @@ 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 *
-
-XXX
-
-=back
-
 =head2 Updated Modules and Pragmata
 
 =over 4
@@ -149,82 +83,83 @@ The F<cpan/podlators/> bundle has been upgraded from version 2.28 to 4.04.
 
 =back
 
-=head2 Removed Modules and Pragmata
+=head1 Documentation
+
+=head2 Changes to Existing Documentation
+
+=head3 L<perlsyn>
 
 =over 4
 
 =item *
 
-XXX
+Fix broken example where C<=> was used instead of
+C<==> in conditional in do/while example.
 
 =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
+=head3 L<perlfunc>
 
-XXX Changes which create B<new> files in F<pod/> go here.
-
-=head3 L<XXX>
+=over 4
 
-XXX Description of the purpose of the new file here
+=item *
 
-=head2 Changes to Existing Documentation
+Better explain meaning of negative PIDs in C<waitpid>.
+L<[perl #127080]|https://rt.perl.org/Ticket/Display.html?id=127080>
 
-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.
+=back
 
-=head3 L<XXX>
+=head3 L<perlgit>
 
 =over 4
 
 =item *
 
-XXX Description of the change here
+Move sample commands into verbatim paragraphs.
 
-=back
+=item *
 
-=head1 Diagnostics
+Improve hyperlinks for all email addresses, RT tickets
+and commit hashes.
 
-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 *
+
+Consistently refer to bisect.pl as F<Porting/bisect.pl>
 
-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.
+=item *
 
-=head2 New Diagnostics
+Misc. grammar and POD fixes.
 
-XXX Newly added diagnostic messages go under here, separated into New Errors
-and New Warnings
+=back
 
-=head3 New Errors
+=head3 L<perlreftut>
 
 =over 4
 
 =item *
 
-XXX L<message|perldiag/"message">
+Fix some examples to be L<strict> clean.
 
 =back
 
-=head3 New Warnings
+=head3 L<perlrebackslash>
 
 =over 4
 
 =item *
 
-XXX L<message|perldiag/"message">
+Clarify that in languages like Japanese and Thai, dictionary lookup
+is required to determine word boundaries.
 
 =back
 
-=head2 Changes to Existing Diagnostics
+=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 Changes (i.e. rewording) of diagnostic messages go here
+=head2 Changes to Existing Diagnostics
 
 =over 4
 
@@ -232,206 +167,189 @@ XXX Changes (i.e. rewording) of diagnostic messages go here
 
 Accessing the C<IO> part of a glob as C<FILEHANDLE> instead of C<IO> is no
 longer deprecated.  It is discouraged to encourage uniformity (so that, for
-example, one can grep more easily) but it will not be removed. [perl #127060]
+example, one can grep more easily) but it will not be removed.
+L<[perl #127060]|https://rt.perl.org/Ticket/Display.html?id=127060>
 
 =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 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>
+=head2 L<podcheck>
 
 =over 4
 
 =item *
 
-XXX
+Improve NAME detection. Previously if the C<=head1> NAME section contained a
+C<=for> block, that caused C<podcheck> to not detect the defined NAME.
 
 =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 *
 
 F<Configure> no longer probes for F<libnm> by default.  Originally
 this was the "New Math" library, but the name has been re-used by the
-GNOME NetworkManager.  [perl #127131]
-
-=back
-
-=head1 Testing
+GNOME NetworkManager.
+L<[perl #127131]|https://rt.perl.org/Ticket/Display.html?id=127131>
 
-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 ]
+=item *
 
-=over 4
+No longer generate EBCDIC POSIX-BC tables.  We don't believe anyone is
+using Perl and POSIX-BC at this time, and by not generating these tables
+it saves time during development, and makes the resulting tar ball smaller.
 
 =item *
 
-XXX
+The Win32 miniperl now has a real C<getcwd> which increases build performance
+resulting in C<getcwd()> being 605x faster in Win32 miniperl.
 
 =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.
+=head2 Platform-Specific Notes
 
 =over 4
 
-=item XXX-some-platform
+=item *
 
-XXX
+On VMS, math function prototypes in C<math.h> now visible under C++. Building
+POSIX extension with C++ no longer crashes.
 
-=back
+=item *
 
-=head2 Discontinued Platforms
+VMS has had C<setenv/unsetenv> since v7.0 (released in 1996), C<Perl_vmssetenv>
+now always uses C<setenv/unsetenv>.
 
-XXX List any platforms that this version of perl no longer compiles on.
+=item *
 
-=over 4
+Try more crypt algorithms in the tests, for OpenBSD. OpenBSD implements the
+Blowfish algorithm, but not the MD5 one used by C<glibc>. Enhance the crypt and
+taint tests to try both algorithms. If neither works, fall back to no algorithm.
+The Blowfish salt is taken from the OpenBSD C<crypt(3)> page.
 
-=item XXX-some-platform
+=item *
 
-XXX
+Use the C<fdclose()> function from FreeBSD if it is available.
+L<[perl #126847]|https://rt.perl.org/Ticket/Display.html?id=126847>
 
 =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.
+=head1 Internal Changes
 
 =over 4
 
-=item XXX-some-platform
+=item *
 
-XXX
+The obscure C<PL_timesbuf> variable, effectively a vestige of Perl 1, has
+been removed. It was documented as deprecated in Perl 5.20, with a statement
+that it would be removed early in the 5.21.x series; that has now finally
+happened.
+L<[perl #121351]|https://rt.perl.org/Ticket/Display.html?id=121351>
 
-=back
+=item *
 
-=head1 Internal Changes
+Remove unwarranted assertion in C<Perl_newATTRSUB_x()>. If a stub subroutine
+definition with a prototype has been seen, then any subsequent stub (or
+definition) of the same subroutine with an attribute was causing an assertion
+failure because of a null pointer.
+L<[perl #126845]|https://rt.perl.org/Ticket/Display.html?id=126845>
 
-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.
+=item *
 
-=over 4
+Replace C<::> with C<__> in C<ExtUtils::ParseXS> like it's done for
+parameters/return values. This is more consistent, and simplifies writing XS
+code wrapping C++ classes into a nested Perl namespace (it requires only
+a typedef for C<Foo__Bar> rather than two, one for C<Foo_Bar> and the other
+for C<Foo::Bar>).
 
 =item *
 
-The obscure C<PL_timesbuf> variable, effectively a vestige of Perl 1, has
-been removed. It was documented as deprecated in Perl 5.20, with a statement
-that it would be removed early in the 5.21.x series; that has now finally
-happened.  [perl #121351]
+Deprecate C<to_utf8_case()> function, see
+L<http://nntp.perl.org/group/perl.perl5.porters/233287>.
 
 =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 *
 
 A regression that allowed undeclared barewords as hash keys to work despite
-strictures has been fixed. [perl #126981]
+strictures has been fixed.
+L<[perl #126981]|https://rt.perl.org/Ticket/Display.html?id=126981>
 
 =item *
 
-Calls to the placeholder C<&PL_sv_yes> used internally when an
-import() or unimport() method isn't found now correctly handle scalar
-context.  [perl #126042]
+Calls to the placeholder C<&PL_sv_yes> used internally when an C<import()>
+or C<unimport()> method isn't found now correctly handle scalar context.
+L<[perl #126042]|https://rt.perl.org/Ticket/Display.html?id=126042>
 
 =item *
 
 Fixed some problems introduced in 5.23.2 with list assignment dealing
-with magic and XS functions returning their arguments.  [perl #126633]
+with magic and XS functions returning their arguments.
+L<[perl #126633]|https://rt.perl.org/Ticket/Display.html?id=126633>
 
 =item *
 
 Report more context when we see an array where we expect to see an
-operator and avoid an assertion failure.  [perl #123737]
+operator and avoid an assertion failure.
+L<[perl #123737]|https://rt.perl.org/Ticket/Display.html?id=123737>
 
 =item *
 
 Modifying an array that was previously a package C<@ISA> no longer
-causes assertion failures or crashes.  [perl #123788]
-
-=back
-
-=head1 Known Problems
+causes assertion failures or crashes.
+L<[perl #123788]|https://rt.perl.org/Ticket/Display.html?id=123788>
 
-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 ]
+=item *
 
-=over 4
+Retain binary compatibility across plain and DEBUGGING perl builds.
+L<[perl #127212]|https://rt.perl.org/Ticket/Display.html?id=127212>
 
 =item *
 
-XXX
+Avoid leaking memory when setting C<$ENV{foo}> on darwin.
+L<[perl #126240]|https://rt.perl.org/Ticket/Display.html?id=126240>
 
 =back
 
-=head1 Errata From Previous Releases
-
-=over 4
-
-=item *
+=head1 Acknowledgements
 
-XXX Add anything here that we forgot to add, or were mistaken about, in
-the perldelta of a previous release.
+Perl 5.23.7 represents approximately 4 weeks of development since Perl 5.23.6
+and contains approximately 87,000 lines of changes across 450 files from 21
+authors.
 
-=back
+Excluding auto-generated files, documentation and release tools, there were
+approximately 67,000 lines of changes to 320 .pm, .t, .c and .h files.
 
-=head1 Obituary
+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 5.23.7:
 
-XXX If any significant core contributor has died, we've added a short obituary
-here.
+Aaron Crane, Andreas König, Andy Dougherty, Chris 'BinGOs' Williams, Craig A.
+Berry, Dagfinn Ilmari Mannsåker, Daniel Dragan, David Golden, David Mitchell,
+James E Keenan, Jarkko Hietaniemi, Karen Etheridge, Karl Williamson, Lukas Mai,
+Mattia Barbon, Ricardo Signes, Stevan Little, Steve Hay, Todd Rinaldo, Tom
+Hukins, Tony Cook.
 
-=head1 Acknowledgements
+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.
 
-XXX Generate this with:
+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.
 
-  perl Porting/acknowledgements.pl v5.23.6..HEAD
+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