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 v5.31.1
12 This document describes differences between the 5.31.0 release and the 5.31.1
15 If you are upgrading from an earlier release such as 5.30.0, first read
16 L<perl5310delta>, which describes differences between 5.30.0 and 5.31.0.
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 not applicable.
122 =head2 Updated Modules and Pragmata
128 L<Storable> has been upgraded from version 3.15 to 3.16.
130 Regular expressions objects weren't properly counted for object id
131 purposes on retrieve. This would corrupt the resulting structure, or
132 cause a runtime error in some cases. [perl #134179]
136 =head2 Removed Modules and Pragmata
142 Pod::Parser has been removed from the core distribution.
143 It still is available for download from CPAN. This resolves [perl
150 XXX Changes to files in F<pod/> go here. Consider grouping entries by
151 file and be sure to link to the appropriate page, e.g. L<perlfunc>.
153 =head2 New Documentation
155 XXX Changes which create B<new> files in F<pod/> go here.
159 XXX Description of the purpose of the new file here
161 =head2 Changes to Existing Documentation
163 We have attempted to update the documentation to reflect the changes
164 listed in this document. If you find any we have missed, send email
165 to L<perlbug@perl.org|mailto:perlbug@perl.org>.
167 XXX Changes which significantly change existing files in F<pod/> go here.
168 However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
171 Additionally, the following selected changes have been made:
179 XXX Description of the change here
185 The following additions or changes have been made to diagnostic output,
186 including warnings and fatal error messages. For the complete list of
187 diagnostic messages, see L<perldiag>.
189 XXX New or changed warnings emitted by the core's C<C> code go here. Also
190 include any changes in L<perldiag> that reconcile it to the C<C> code.
192 =head2 New Diagnostics
194 XXX Newly added diagnostic messages go under here, separated into New Errors
203 XXX L<message|perldiag/"message">
213 XXX L<message|perldiag/"message">
217 =head2 Changes to Existing Diagnostics
219 XXX Changes (i.e. rewording) of diagnostic messages go here
225 XXX Describe change here
229 =head1 Utility Changes
231 XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go here.
232 Most of these are built within the directory F<utils>.
234 [ List utility changes as a =head2 entry for each utility and =item
235 entries for each change
236 Use L<XXX> with program names to get proper documentation linking. ]
248 =head1 Configuration and Compilation
250 XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
251 go here. Any other changes to the Perl build process should be listed here.
252 However, any platform-specific changes should be listed in the
253 L</Platform Support> section, instead.
255 [ List changes as an =item entry ].
267 XXX Any significant changes to the testing of a freshly built perl should be
268 listed here. Changes which create B<new> files in F<t/> go here as do any
269 large changes to the testing harness (e.g. when parallel testing was added).
270 Changes to existing files in F<t/> aren't worth summarizing, although the bugs
271 that they represent may be covered elsewhere.
273 XXX If there were no significant test changes, say this:
275 Tests were added and changed to reflect the other additions and changes
278 XXX If instead there were significant changes, say this:
280 Tests were added and changed to reflect the other additions and
281 changes in this release. Furthermore, these significant changes were
284 [ List each test improvement as an =item entry ]
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 L<eval_pv()|perlapi/eval_pv> no longer stringifies the exception when
356 C<croak_on_error> is true. [perl #134175]
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 an =item entry ]
371 close() on a pipe now preemptively clears the PerlIO object from the
372 IO SV. This prevents a second attempt to close the already closed
373 PerlIO object if a signal handler calls die() or exit() while close()
374 is waiting for the child process to complete. [perl #122112]
378 C<< sprintf("%.*a", -10000, $x) >> would cause a buffer overflow due
379 to mishandling of the negative precision value. [perl #134008]
383 scalar() on a reference could cause an erroneous assertion failure
384 during compilation. [perl #134045]
388 Extraordinarily large (over 2GB) floating point format widths could
389 cause an integer overflow in the underlying call to snprintf(),
390 resulting in an assertion. Formatted floating point widths are now
391 limited to the range of int, the return value of snprintf(). [perl
396 Parsing the following constructs within a sub-parse (such as with
397 C<"${code here}"> or C<s/.../code here/e>) has changed to match how
398 they're parsed normally:
404 C<print $fh ...> no longer produces a syntax error.
408 Code like C<s/.../ ${time} /e> now properly produces an "Ambiguous use
409 of ${time} resolved to $time at ..." warning when warnings are enabled.
413 C<@x {"a"}> (with the space) in a sub-parse now properly produces a
414 "better written as" warning when warnings are enabled.
418 attributes can now be used in a sub-parse.
426 Incomplete hex and binary literals like C<0x> and C<0b> are now
427 treated as if the C<x> or C<b> is part of the next token. [perl
432 A spurious C<)> in a subparse, such as in C<s/.../code here/e> or
433 C<"...${code here}">, no longer confuses the parser.
435 Previously a subparse was bracketed with generated C<(> and C<)>
436 tokens, so a spurious C<)> would close the construct without doing the
437 normal subparse clean up, confusing the parser and possible causing an
440 Such constructs are now surrounded by artificial tokens that can't be
441 included in the source. [perl #130585]
445 =head1 Known Problems
447 XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
448 tests that had to be C<TODO>ed for the release would be noted here. Unfixed
449 platform specific bugs also go here.
451 [ List each fix as an =item entry ]
461 =head1 Errata From Previous Releases
467 XXX Add anything here that we forgot to add, or were mistaken about, in
468 the perldelta of a previous release.
474 XXX If any significant core contributor or member of the CPAN community has
475 died, add a short obituary here.
477 =head1 Acknowledgements
479 XXX Generate this with:
481 perl Porting/acknowledgements.pl v5.31.0..HEAD
483 =head1 Reporting Bugs
485 If you find what you think is a bug, you might check the perl bug database
486 at L<https://rt.perl.org/>. There may also be information at
487 L<http://www.perl.org/>, the Perl Home Page.
489 If you believe you have an unreported bug, please run the L<perlbug> program
490 included with your release. Be sure to trim your bug down to a tiny but
491 sufficient test case. Your bug report, along with the output of C<perl -V>,
492 will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
494 If the bug you are reporting has security implications which make it
495 inappropriate to send to a publicly archived mailing list, then see
496 L<perlsec/SECURITY VULNERABILITY CONTACT INFORMATION>
497 for details of how to report the issue.
501 If you wish to thank the Perl 5 Porters for the work we had done in Perl 5,
502 you can do so by running the C<perlthanks> program:
506 This will send an email to the Perl 5 Porters list with your show of thanks.
510 The F<Changes> file for an explanation of how to view exhaustive details on
513 The F<INSTALL> file for how to build Perl.
515 The F<README> file for general stuff.
517 The F<Artistic> and F<Copying> files for copyright information.