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Finish prepping Module::CoreList for 5.31.5
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1=encoding utf8
2
3=head1 NAME
4
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5[ this is a template for a new perldelta file. Any text flagged as XXX needs
6to be processed before release. ]
7
8perldelta - what is new for perl v5.31.5
d407e309 9
862f380b 10=head1 DESCRIPTION
261e14b0 11
74c14c97 12This document describes differences between the 5.31.4 release and the 5.31.5
862f380b 13release.
261e14b0 14
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15If you are upgrading from an earlier release such as 5.31.3, first read
16L<perl5314delta>, which describes differences between 5.31.3 and 5.31.4.
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17
18=head1 Notice
19
74c14c97 20XXX Any important notices here
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21
22=head1 Core Enhancements
23
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24XXX New core language features go here. Summarize user-visible core language
25enhancements. Particularly prominent performance optimisations could go
26here, but most should go in the L</Performance Enhancements> section.
27
28[ List each enhancement as a =head2 entry ]
29
30=head1 Security
fd41b2d1 31
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32XXX Any security-related notices go here. In particular, any security
33vulnerabilities closed should be noted here rather than in the
34L</Selected Bug Fixes> section.
35
36[ List each security issue as a =head2 entry ]
fd41b2d1 37
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38=head1 Incompatible Changes
39
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40XXX For a release on a stable branch, this section aspires to be:
41
42 There are no changes intentionally incompatible with 5.XXX.XXX
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43 If any exist, they are bugs, and we request that you submit a
44 report. See L</Reporting Bugs> below.
e6132dc0 45
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46[ List each incompatible change as a =head2 entry ]
47
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48=head2 Modifiable variables are no longer permitted in constants
49
50Code like:
51
52 my $var;
53 $sub = sub () { $var };
54
55where C<$var> is referenced elsewhere in some sort of modiable context
56now produces an exception when the sub is defined.
57
58This error can be avoided by adding a return to the sub definition:
59
60 $sub = sub () { return $var };
61
62This has been deprecated since perl 5.22.
63
64[perl #131138]
65
fcbec156 66=head1 Deprecations
e6132dc0 67
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68XXX Any deprecated features, syntax, modules etc. should be listed here.
69
fcbec156 70=head2 Module removals
befef368 71
74c14c97 72XXX Remove this section if not applicable.
befef368 73
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74The following modules will be removed from the core distribution in a
75future release, and will at that time need to be installed from CPAN.
76Distributions on CPAN which require these modules will need to list them as
77prerequisites.
fcbec156 78
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79The core versions of these modules will now issue C<"deprecated">-category
80warnings to alert you to this fact. To silence these deprecation warnings,
81install the modules in question from CPAN.
fcbec156 82
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83Note that these are (with rare exceptions) fine modules that you are encouraged
84to continue to use. Their disinclusion from core primarily hinges on their
85necessity to bootstrapping a fully functional, CPAN-capable Perl installation,
86not usually on concerns over their design.
fcbec156 87
74c14c97 88=over
fcbec156 89
74c14c97 90=item XXX
fcbec156 91
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92XXX Note that deprecated modules should be listed here even if they are listed
93as an updated module in the L</Modules and Pragmata> section.
94
95=back
96
97[ List each other deprecation as a =head2 entry ]
98
99=head1 Performance Enhancements
100
101XXX Changes which enhance performance without changing behaviour go here.
102There may well be none in a stable release.
103
104[ List each enhancement as an =item entry ]
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105
106=over 4
a0348300 107
9c600b76 108=item *
a0348300 109
74c14c97 110XXX
be2eb09e 111
74c14c97 112=back
fcbec156 113
74c14c97 114=head1 Modules and Pragmata
be2eb09e 115
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116XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
117go here. If Module::CoreList is updated, generate an initial draft of the
118following sections using F<Porting/corelist-perldelta.pl>. A paragraph summary
119for important changes should then be added by hand. In an ideal world,
120dual-life modules would have a F<Changes> file that could be cribbed.
be2eb09e 121
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122The list of new and updated modules is modified automatically as part of
123preparing a Perl release, so the only reason to manually add entries here is if
124you're summarising the important changes in the module update. (Also, if the
125manually-added details don't match the automatically-generated ones, the
126release manager will have to investigate the situation carefully.)
be2eb09e 127
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128[ Within each section, list entries as an =item entry ]
129
130=head2 New Modules and Pragmata
03b7d279 131
74c14c97 132=over 4
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133
134=item *
135
74c14c97 136XXX Remove this section if not applicable.
03b7d279 137
74c14c97 138=back
03b7d279 139
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140=head2 Updated Modules and Pragmata
141
142=over 4
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143
144=item *
145
74c14c97 146L<XXX> has been upgraded from version A.xx to B.yy.
c8d86fdc 147
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148If there was something important to note about this change, include that here.
149
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150=item *
151
152L<Dumpvalue> has been upgraded from version 1.18 to 1.21.
153
154Previously, when dumping elements of an array and encountering an undefined
155value, the string printed would have been C<empty array>. This has been
156changed to what was apparently originally intended: C<empty slot>.
157
74c14c97 158=back
c8d86fdc 159
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160=head2 Removed Modules and Pragmata
161
162=over 4
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163
164=item *
165
74c14c97 166XXX
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167
168=back
169
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170=head1 Documentation
171
172XXX Changes to files in F<pod/> go here. Consider grouping entries by
173file and be sure to link to the appropriate page, e.g. L<perlfunc>.
fcbec156 174
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175=head2 New Documentation
176
177XXX Changes which create B<new> files in F<pod/> go here.
178
179=head3 L<XXX>
180
181XXX Description of the purpose of the new file here
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182
183=head2 Changes to Existing Documentation
184
185We have attempted to update the documentation to reflect the changes
186listed in this document. If you find any we have missed, send email
187to L<perlbug@perl.org|mailto:perlbug@perl.org>.
188
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189XXX Changes which significantly change existing files in F<pod/> go here.
190However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
191section.
192
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193Additionally, the following selected changes have been made:
194
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195=head3 URLs have been changed to https://, stale links updated
196
197=over 4
198
199=item *
200
201Where applicable, the URLs in the documentation have been moved from
202using the http:// protocol to https:// . This also affects the location
203of the bug tracker at L<https://rt.perl.org>.
204
205=item *
206
207Some links to OS/2 libraries, Address Sanitizer and other system tools
208had gone stale. These have been updated with working links.
209
210=item *
211
212Some links to old mails on perl5-porters had gone stale. These have been
213updated with working links.
214
215=back
216
74c14c97 217=head3 L<XXX>
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218
219=over 4
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220
221=item *
222
74c14c97 223XXX Description of the change here
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224
225=back
226
227=head1 Diagnostics
228
229The following additions or changes have been made to diagnostic output,
230including warnings and fatal error messages. For the complete list of
231diagnostic messages, see L<perldiag>.
232
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233XXX New or changed warnings emitted by the core's C<C> code go here. Also
234include any changes in L<perldiag> that reconcile it to the C<C> code.
235
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236=head2 New Diagnostics
237
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238XXX Newly added diagnostic messages go under here, separated into New Errors
239and New Warnings
240
241=head3 New Errors
242
243=over 4
244
245=item *
246
247XXX L<message|perldiag/"message">
248
249=back
250
251=head3 New Warnings
252
253=over 4
254
255=item *
256
257XXX L<message|perldiag/"message">
258
259=back
260
261=head2 Changes to Existing Diagnostics
262
263XXX Changes (i.e. rewording) of diagnostic messages go here
264
265=over 4
266
267=item *
268
269XXX Describe change here
270
271=back
272
273=head1 Utility Changes
274
275XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go here.
276Most of these are built within the directory F<utils>.
277
278[ List utility changes as a =head2 entry for each utility and =item
279entries for each change
280Use L<XXX> with program names to get proper documentation linking. ]
281
282=head2 L<XXX>
283
284=over 4
285
286=item *
287
288XXX
289
290=back
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291
292=head1 Configuration and Compilation
293
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294XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
295go here. Any other changes to the Perl build process should be listed here.
296However, any platform-specific changes should be listed in the
297L</Platform Support> section, instead.
298
299[ List changes as an =item entry ].
300
fcbec156 301=over 4
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302
303=item *
304
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305Perl now no longer probes for C<d_u32align>, defaulting to C<define>
306on all platforms. This check was error prone when it was done, which
307was on 32-bit platforms only. [perl #133495]
06bfb2b1 308
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309=item *
310
311Documentation and hints for building perl on Z/OS (native EBCDIC) have
312been updated. Still work in progress.
313
314=item *
315
316New probe for malloc_usable_size
317
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318=back
319
320=head1 Testing
321
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322XXX Any significant changes to the testing of a freshly built perl should be
323listed here. Changes which create B<new> files in F<t/> go here as do any
324large changes to the testing harness (e.g. when parallel testing was added).
325Changes to existing files in F<t/> aren't worth summarizing, although the bugs
326that they represent may be covered elsewhere.
327
328XXX If there were no significant test changes, say this:
329
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330Tests were added and changed to reflect the other additions and changes
331in this release.
332
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333XXX If instead there were significant changes, say this:
334
335Tests were added and changed to reflect the other additions and
336changes in this release. Furthermore, these significant changes were
337made:
338
339[ List each test improvement as an =item entry ]
340
341=over 4
342
343=item *
344
345XXX
346
347=back
348
dad02c36 349=head1 Platform Support
8424e368 350
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351XXX Any changes to platform support should be listed in the sections below.
352
353[ Within the sections, list each platform as an =item entry with specific
354changes as paragraphs below it. ]
355
356=head2 New Platforms
357
358XXX List any platforms that this version of perl compiles on, that previous
359versions did not. These will either be enabled by new files in the F<hints/>
360directories, or new subdirectories and F<README> files at the top level of the
361source tree.
362
363=over 4
364
365=item XXX-some-platform
366
367XXX
368
369=back
370
371=head2 Discontinued Platforms
372
373XXX List any platforms that this version of perl no longer compiles on.
fcbec156 374
fcbec156 375=over 4
061637ca 376
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377=item XXX-some-platform
378
379XXX
380
381=back
382
383=head2 Platform-Specific Notes
fcbec156 384
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385XXX List any changes for specific platforms. This could include configuration
386and compilation changes or changes in portability/compatibility. However,
387changes within modules for platforms should generally be listed in the
388L</Modules and Pragmata> section.
389
390=over 4
0076a047 391
2e1181e2 392=item Windows
74c14c97 393
2e1181e2 394Support for building perl with Visual C++ 6.0 has now been removed.
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395
396=back
397
398=head1 Internal Changes
399
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400XXX Changes which affect the interface available to C<XS> code go here. Other
401significant internal changes for future core maintainers should be noted as
402well.
403
404[ List each change as an =item entry ]
405
fcbec156 406=over 4
061637ca 407
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408=item *
409
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410Added the C<<PL_curstackinfo->si_cxsubix>> field. This records the stack
411index of the most recently pushed sub/format/eval context. It is set and
412restored automatically by C<cx_pushsub()>, C<cx_popsub()> etc., but would
413need to be manually managed if you do any unusual manipulation of the
414context stack.
285db695 415
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416=item *
417
418Various macros dealing with character type classification and changing
419case where the input is encoded in UTF-8 now require an extra parameter
420to prevent potential reads beyond the end of the buffer. Use of these
421has generated a deprecation warning since 5.26. Details are in
422L<perldeprecation/In XS code, use of various macros dealing with UTF-8.>
423
9064626f 424=back
ed0cf058 425
9064626f 426=head1 Selected Bug Fixes
ed0cf058 427
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428XXX Important bug fixes in the core language are summarized here. Bug fixes in
429files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
430
431[ List each fix as an =item entry ]
432
9064626f 433=over 4
973ae088 434
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435=item *
436
74c14c97 437XXX
f7faf2ad 438
74c14c97 439=back
8714ff4f 440
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441=head1 Known Problems
442
443XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
444tests that had to be C<TODO>ed for the release would be noted here. Unfixed
445platform specific bugs also go here.
446
447[ List each fix as an =item entry ]
448
449=over 4
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451=item *
452
74c14c97 453XXX
7118f704 454
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455=back
456
74c14c97 457=head1 Errata From Previous Releases
fcbec156 458
74c14c97 459=over 4
a3c77565 460
74c14c97 461=item *
fcbec156 462
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463XXX Add anything here that we forgot to add, or were mistaken about, in
464the perldelta of a previous release.
bd833cba 465
74c14c97 466=back
bd833cba 467
74c14c97 468=head1 Obituary
bd833cba 469
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470XXX If any significant core contributor or member of the CPAN community has
471died, add a short obituary here.
bd833cba 472
74c14c97 473=head1 Acknowledgements
bd833cba 474
74c14c97 475XXX Generate this with:
bd833cba 476
74c14c97 477 perl Porting/acknowledgements.pl v5.31.4..HEAD
8424e368 478
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479=head1 Reporting Bugs
480
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481If you find what you think is a bug, you might check the perl bug database
482at L<https://rt.perl.org/>. There may also be information at
71c89d21 483L<https://www.perl.org/>, the Perl Home Page.
44691e6f 484
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485If you believe you have an unreported bug, please run the L<perlbug> program
486included with your release. Be sure to trim your bug down to a tiny but
487sufficient test case. Your bug report, along with the output of C<perl -V>,
0e18d1c4 488will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
44691e6f 489
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490If the bug you are reporting has security implications which make it
491inappropriate to send to a publicly archived mailing list, then see
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492L<perlsec/SECURITY VULNERABILITY CONTACT INFORMATION>
493for details of how to report the issue.
44691e6f 494
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495=head1 Give Thanks
496
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497If you wish to thank the Perl 5 Porters for the work we had done in Perl 5,
498you can do so by running the C<perlthanks> program:
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499
500 perlthanks
501
502This will send an email to the Perl 5 Porters list with your show of thanks.
503
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504=head1 SEE ALSO
505
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506The F<Changes> file for an explanation of how to view exhaustive details on
507what changed.
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508
509The F<INSTALL> file for how to build Perl.
510
511The F<README> file for general stuff.
512
513The F<Artistic> and F<Copying> files for copyright information.
514
515=cut