5 [ this is a template for a new perldelta file. Any text flagged as XXX needs
6 to be processed before release. ]
8 perldelta - what is new for perl v5.21.10
12 This document describes differences between the 5.21.9 release and the 5.21.10
15 If you are upgrading from an earlier release such as 5.21.8, first read
16 L<perl5219delta>, which describes differences between 5.21.8 and 5.21.9.
20 XXX Any important notices here
22 =head1 Core Enhancements
24 XXX New core language features go here. Summarize user-visible core language
25 enhancements. Particularly prominent performance optimisations could go
26 here, but most should go in the L</Performance Enhancements> section.
28 [ List each enhancement as a =head2 entry ]
32 XXX Any security-related notices go here. In particular, any security
33 vulnerabilities closed should be noted here rather than in the
34 L</Selected Bug Fixes> section.
36 [ List each security issue as a =head2 entry ]
38 =head1 Incompatible Changes
40 XXX For a release on a stable branch, this section aspires to be:
42 There are no changes intentionally incompatible with 5.XXX.XXX
43 If any exist, they are bugs, and we request that you submit a
44 report. See L</Reporting Bugs> below.
46 [ List each incompatible change as a =head2 entry ]
50 XXX Any deprecated features, syntax, modules etc. should be listed here.
52 =head2 Module removals
54 XXX Remove this section if inapplicable.
56 The following modules will be removed from the core distribution in a
57 future release, and will at that time need to be installed from CPAN.
58 Distributions on CPAN which require these modules will need to list them as
61 The core versions of these modules will now issue C<"deprecated">-category
62 warnings to alert you to this fact. To silence these deprecation warnings,
63 install the modules in question from CPAN.
65 Note that these are (with rare exceptions) fine modules that you are encouraged
66 to continue to use. Their disinclusion from core primarily hinges on their
67 necessity to bootstrapping a fully functional, CPAN-capable Perl installation,
68 not usually on concerns over their design.
74 XXX Note that deprecated modules should be listed here even if they are listed
75 as an updated module in the L</Modules and Pragmata> section.
79 [ List each other deprecation as a =head2 entry ]
81 =head1 Performance Enhancements
83 XXX Changes which enhance performance without changing behaviour go here.
84 There may well be none in a stable release.
86 [ List each enhancement as a =item entry ]
96 =head1 Modules and Pragmata
98 XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
99 go here. If Module::CoreList is updated, generate an initial draft of the
100 following sections using F<Porting/corelist-perldelta.pl>. A paragraph summary
101 for important changes should then be added by hand. In an ideal world,
102 dual-life modules would have a F<Changes> file that could be cribbed.
104 [ Within each section, list entries as a =item entry ]
106 =head2 New Modules and Pragmata
116 =head2 Updated Modules and Pragmata
122 L<CPAN> has been upgraded from version 2.05 to 2.09-TRIAL.
128 Add support for C<Cwd::getdcwd()> and introduce workaround for a misbehaviour
129 seen on Strawberry Perl 5.20.1.
133 Fix C<chdir()> after building dependencies bug.
137 Introduce experimental support for plugins/hooks.
141 Integrate the App::Cpan sources.
145 Do not check recursion on optional dependencies.
149 Sanity check META.yml to contain a hash.
150 L<[cpan #95271]|https://rt.cpan.org/Ticket/Display.html?id=95271>
156 =head2 Removed Modules and Pragmata
168 XXX Changes to files in F<pod/> go here. Consider grouping entries by
169 file and be sure to link to the appropriate page, e.g. L<perlfunc>.
171 =head2 New Documentation
173 XXX Changes which create B<new> files in F<pod/> go here.
177 XXX Description of the purpose of the new file here
179 =head2 Changes to Existing Documentation
181 XXX Changes which significantly change existing files in F<pod/> go here.
182 However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
191 XXX Description of the change here
197 The following additions or changes have been made to diagnostic output,
198 including warnings and fatal error messages. For the complete list of
199 diagnostic messages, see L<perldiag>.
201 XXX New or changed warnings emitted by the core's C<C> code go here. Also
202 include any changes in L<perldiag> that reconcile it to the C<C> code.
204 =head2 New Diagnostics
206 XXX Newly added diagnostic messages go under here, separated into New Errors
215 XXX L<message|perldiag/"message">
225 XXX L<message|perldiag/"message">
229 =head2 Changes to Existing Diagnostics
231 XXX Changes (i.e. rewording) of diagnostic messages go here
237 XXX Describe change here
241 =head1 Utility Changes
243 XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go here.
244 Most of these are built within the directory F<utils>.
246 [ List utility changes as a =head2 entry for each utility and =item
247 entries for each change
248 Use L<XXX> with program names to get proper documentation linking. ]
260 =head1 Configuration and Compilation
262 XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
263 go here. Any other changes to the Perl build process should be listed here.
264 However, any platform-specific changes should be listed in the
265 L</Platform Support> section, instead.
267 [ List changes as a =item entry ].
279 XXX Any significant changes to the testing of a freshly built perl should be
280 listed here. Changes which create B<new> files in F<t/> go here as do any
281 large changes to the testing harness (e.g. when parallel testing was added).
282 Changes to existing files in F<t/> aren't worth summarizing, although the bugs
283 that they represent may be covered elsewhere.
285 [ List each test improvement as a =item entry ]
295 =head1 Platform Support
297 XXX Any changes to platform support should be listed in the sections below.
299 [ Within the sections, list each platform as a =item entry with specific
300 changes as paragraphs below it. ]
304 XXX List any platforms that this version of perl compiles on, that previous
305 versions did not. These will either be enabled by new files in the F<hints/>
306 directories, or new subdirectories and F<README> files at the top level of the
311 =item XXX-some-platform
317 =head2 Discontinued Platforms
319 XXX List any platforms that this version of perl no longer compiles on.
323 =item XXX-some-platform
329 =head2 Platform-Specific Notes
331 XXX List any changes for specific platforms. This could include configuration
332 and compilation changes or changes in portability/compatibility. However,
333 changes within modules for platforms should generally be listed in the
334 L</Modules and Pragmata> section.
338 =item XXX-some-platform
344 =head1 Internal Changes
346 XXX Changes which affect the interface available to C<XS> code go here. Other
347 significant internal changes for future core maintainers should be noted as
350 [ List each change as a =item entry ]
360 =head1 Selected Bug Fixes
362 XXX Important bug fixes in the core language are summarized here. Bug fixes in
363 files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
365 [ List each fix as a =item entry ]
371 Repeated global pattern matches in scalar context on large tainted
372 strings were exponentially slow depending on the current match
373 position in the string. [perl #123202]
377 =head1 Known Problems
379 XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
380 tests that had to be C<TODO>ed for the release would be noted here. Unfixed
381 platform specific bugs also go here.
383 [ List each fix as a =item entry ]
393 =head1 Errata From Previous Releases
399 XXX Add anything here that we forgot to add, or were mistaken about, in
400 the perldelta of a previous release.
406 XXX If any significant core contributor has died, we've added a short obituary
409 =head1 Acknowledgements
411 XXX Generate this with:
413 perl Porting/acknowledgements.pl v5.21.9..HEAD
415 =head1 Reporting Bugs
417 If you find what you think is a bug, you might check the articles recently
418 posted to the comp.lang.perl.misc newsgroup and the perl bug database at
419 https://rt.perl.org/ . There may also be information at
420 http://www.perl.org/ , the Perl Home Page.
422 If you believe you have an unreported bug, please run the L<perlbug> program
423 included with your release. Be sure to trim your bug down to a tiny but
424 sufficient test case. Your bug report, along with the output of C<perl -V>,
425 will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
427 If the bug you are reporting has security implications, which make it
428 inappropriate to send to a publicly archived mailing list, then please send it
429 to perl5-security-report@perl.org. This points to a closed subscription
430 unarchived mailing list, which includes all the core committers, who will be
431 able to help assess the impact of issues, figure out a resolution, and help
432 co-ordinate the release of patches to mitigate or fix the problem across all
433 platforms on which Perl is supported. Please only use this address for
434 security issues in the Perl core, not for modules independently distributed on
439 The F<Changes> file for an explanation of how to view exhaustive details on
442 The F<INSTALL> file for how to build Perl.
444 The F<README> file for general stuff.
446 The F<Artistic> and F<Copying> files for copyright information.