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 v5.39.3
12 This document describes differences between the 5.39.2 release and the 5.39.3
15 If you are upgrading from an earlier release such as 5.39.1, first read
16 L<perl5392delta>, which describes differences between 5.39.1 and 5.39.2.
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 not applicable.
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 an =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 The list of new and updated modules is modified automatically as part of
105 preparing a Perl release, so the only reason to manually add entries here is if
106 you're summarising the important changes in the module update. (Also, if the
107 manually-added details don't match the automatically-generated ones, the
108 release manager will have to investigate the situation carefully.)
110 [ Within each section, list entries as an =item entry ]
112 =head2 New Modules and Pragmata
118 XXX Remove this section if Porting/corelist-perldelta.pl did not add any content here.
122 =head2 Updated Modules and Pragmata
128 L<XXX> has been upgraded from version A.xx to B.yy.
130 XXX If there was something important to note about this change, include that here.
134 =head2 Removed Modules and Pragmata
140 XXX Remove this section if Porting/corelist-perldelta.pl did not add any content here.
146 XXX Changes to files in F<pod/> go here. Consider grouping entries by
147 file and be sure to link to the appropriate page, e.g. L<perlfunc>.
149 =head2 New Documentation
151 XXX Changes which create B<new> files in F<pod/> go here.
155 XXX Description of the purpose of the new file here
157 =head2 Changes to Existing Documentation
159 We have attempted to update the documentation to reflect the changes
160 listed in this document. If you find any we have missed, open an issue
161 at L<https://github.com/Perl/perl5/issues>.
163 XXX Changes which significantly change existing files in F<pod/> go here.
164 However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
167 Additionally, the following selected changes have been made:
175 XXX Description of the change here
181 The following additions or changes have been made to diagnostic output,
182 including warnings and fatal error messages. For the complete list of
183 diagnostic messages, see L<perldiag>.
185 XXX New or changed warnings emitted by the core's C<C> code go here. Also
186 include any changes in L<perldiag> that reconcile it to the C<C> code.
188 =head2 New Diagnostics
190 XXX Newly added diagnostic messages go under here, separated into New Errors
199 XXX L<message|perldiag/"message">
209 XXX L<message|perldiag/"message">
213 =head2 Changes to Existing Diagnostics
215 XXX Changes (i.e. rewording) of diagnostic messages go here
221 XXX Describe change here
225 =head1 Utility Changes
227 XXX Changes to installed programs such as F<perldoc> and F<xsubpp> go here.
228 Most of these are built within the directory F<utils>.
230 [ List utility changes as a =head2 entry for each utility and =item
231 entries for each change
232 Use L<XXX> with program names to get proper documentation linking. ]
244 =head1 Configuration and Compilation
246 XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
247 go here. Any other changes to the Perl build process should be listed here.
248 However, any platform-specific changes should be listed in the
249 L</Platform Support> section, instead.
251 [ List changes as an =item entry ].
257 Fix here-doc used for code to probe C<LC_ALL> syntax for disparate
258 locales introduced in 5.39.2. [GH #21451]
264 XXX Any significant changes to the testing of a freshly built perl should be
265 listed here. Changes which create B<new> files in F<t/> go here as do any
266 large changes to the testing harness (e.g. when parallel testing was added).
267 Changes to existing files in F<t/> aren't worth summarizing, although the bugs
268 that they represent may be covered elsewhere.
270 XXX If there were no significant test changes, say this:
272 Tests were added and changed to reflect the other additions and changes
275 XXX If instead there were significant changes, say this:
277 Tests were added and changed to reflect the other additions and
278 changes in this release. Furthermore, these significant changes were
281 [ List each test improvement as an =item entry ]
287 F<t/op/magic.t> would fail when C<ps> was the BusyBox implementation,
288 since that doesn't support the C<-p> flag and otherwise ignores a
289 process id on the command-line. This caused F<TEST> failures on
290 BusyBox systems such as Alpine Linux. [GH #17542]
294 =head1 Platform Support
296 XXX Any changes to platform support should be listed in the sections below.
298 [ Within the sections, list each platform as an =item entry with specific
299 changes as paragraphs below it. ]
303 XXX List any platforms that this version of perl compiles on, that previous
304 versions did not. These will either be enabled by new files in the F<hints/>
305 directories, or new subdirectories and F<README> files at the top level of the
310 =item XXX-some-platform
316 =head2 Discontinued Platforms
318 XXX List any platforms that this version of perl no longer compiles on.
322 =item XXX-some-platform
328 =head2 Platform-Specific Notes
330 XXX List any changes for specific platforms. This could include configuration
331 and compilation changes or changes in portability/compatibility. However,
332 changes within modules for platforms should generally be listed in the
333 L</Modules and Pragmata> section.
337 =item XXX-some-platform
343 =head1 Internal Changes
345 XXX Changes which affect the interface available to C<XS> code go here. Other
346 significant internal changes for future core maintainers should be noted as
349 [ List each change as an =item entry ]
355 A new API function has been added that simplifies C (or XS) code that creates
356 C<LISTOP> optree fragments. C<newLISTOPn()> is a variadic function that takes
357 a C<NULL>-terminated list of child op pointers, and constructs a new checked
358 C<LISTOP> to contain them all. This is simpler than creating a new plain
359 C<OP_LIST>, adding each child individually, and finally calling
360 C<op_convert_list()> in most code fragments.
364 The C<eval_sv()> API now accepts the C<G_USEHINTS> flag, which uses
365 the hints such as strict and features from C<PL_curcop> instead of the
366 default, which is to use default hints, e.g. no C<use vX.XX;>, no
367 strict, default features.
369 Beware if you use this flag in XS code: your evaluated code will need
370 to support whatever strictness or features are in effect at the point
371 your XS function is called.
377 =head1 Selected Bug Fixes
379 XXX Important bug fixes in the core language are summarized here. Bug fixes in
380 files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
382 Include references to GitHub issues and PRs as: [GH #12345] and the release
383 manager will later use a regex to expand these into links.
385 [ List each fix as an =item entry ]
391 Declared references can now be used with C<state> variables. [GH #21351]
395 Trailing elements in an C<unshift>ed and resized array will now always be
396 initialized. [GH #21265]
400 =head1 Known Problems
402 XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
403 tests that had to be C<TODO>ed for the release would be noted here. Unfixed
404 platform specific bugs also go here.
406 [ List each fix as an =item entry ]
416 =head1 Errata From Previous Releases
422 XXX Add anything here that we forgot to add, or were mistaken about, in
423 the perldelta of a previous release.
429 XXX If any significant core contributor or member of the CPAN community has
430 died, add a short obituary here.
432 =head1 Acknowledgements
434 XXX Generate this with:
436 perl Porting/acknowledgements.pl v5.39.2..HEAD
438 =head1 Reporting Bugs
440 If you find what you think is a bug, you might check the perl bug database
441 at L<https://github.com/Perl/perl5/issues>. There may also be information at
442 L<http://www.perl.org/>, the Perl Home Page.
444 If you believe you have an unreported bug, please open an issue at
445 L<https://github.com/Perl/perl5/issues>. Be sure to trim your bug down to a
446 tiny but sufficient test case.
448 If the bug you are reporting has security implications which make it
449 inappropriate to send to a public issue tracker, then see
450 L<perlsec/SECURITY VULNERABILITY CONTACT INFORMATION>
451 for details of how to report the issue.
455 If you wish to thank the Perl 5 Porters for the work we had done in Perl 5,
456 you can do so by running the C<perlthanks> program:
460 This will send an email to the Perl 5 Porters list with your show of thanks.
464 The F<Changes> file for an explanation of how to view exhaustive details on
467 The F<INSTALL> file for how to build Perl.
469 The F<README> file for general stuff.
471 The F<Artistic> and F<Copying> files for copyright information.