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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
150=back
c8d86fdc 151
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152=head2 Removed Modules and Pragmata
153
154=over 4
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155
156=item *
157
74c14c97 158XXX
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159
160=back
161
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162=head1 Documentation
163
164XXX Changes to files in F<pod/> go here. Consider grouping entries by
165file and be sure to link to the appropriate page, e.g. L<perlfunc>.
fcbec156 166
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167=head2 New Documentation
168
169XXX Changes which create B<new> files in F<pod/> go here.
170
171=head3 L<XXX>
172
173XXX Description of the purpose of the new file here
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174
175=head2 Changes to Existing Documentation
176
177We have attempted to update the documentation to reflect the changes
178listed in this document. If you find any we have missed, send email
179to L<perlbug@perl.org|mailto:perlbug@perl.org>.
180
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181XXX Changes which significantly change existing files in F<pod/> go here.
182However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
183section.
184
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185Additionally, the following selected changes have been made:
186
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187=head3 URLs have been changed to https://, stale links updated
188
189=over 4
190
191=item *
192
193Where applicable, the URLs in the documentation have been moved from
194using the http:// protocol to https:// . This also affects the location
195of the bug tracker at L<https://rt.perl.org>.
196
197=item *
198
199Some links to OS/2 libraries, Address Sanitizer and other system tools
200had gone stale. These have been updated with working links.
201
202=item *
203
204Some links to old mails on perl5-porters had gone stale. These have been
205updated with working links.
206
207=back
208
74c14c97 209=head3 L<XXX>
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210
211=over 4
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212
213=item *
214
74c14c97 215XXX Description of the change here
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216
217=back
218
219=head1 Diagnostics
220
221The following additions or changes have been made to diagnostic output,
222including warnings and fatal error messages. For the complete list of
223diagnostic messages, see L<perldiag>.
224
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225XXX New or changed warnings emitted by the core's C<C> code go here. Also
226include any changes in L<perldiag> that reconcile it to the C<C> code.
227
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228=head2 New Diagnostics
229
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230XXX Newly added diagnostic messages go under here, separated into New Errors
231and New Warnings
232
233=head3 New Errors
234
235=over 4
236
237=item *
238
239XXX L<message|perldiag/"message">
240
241=back
242
243=head3 New Warnings
244
245=over 4
246
247=item *
248
249XXX L<message|perldiag/"message">
250
251=back
252
253=head2 Changes to Existing Diagnostics
254
255XXX Changes (i.e. rewording) of diagnostic messages go here
256
257=over 4
258
259=item *
260
261XXX Describe change here
262
263=back
264
265=head1 Utility Changes
266
267XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go here.
268Most of these are built within the directory F<utils>.
269
270[ List utility changes as a =head2 entry for each utility and =item
271entries for each change
272Use L<XXX> with program names to get proper documentation linking. ]
273
274=head2 L<XXX>
275
276=over 4
277
278=item *
279
280XXX
281
282=back
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283
284=head1 Configuration and Compilation
285
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286XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
287go here. Any other changes to the Perl build process should be listed here.
288However, any platform-specific changes should be listed in the
289L</Platform Support> section, instead.
290
291[ List changes as an =item entry ].
292
fcbec156 293=over 4
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294
295=item *
296
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297Perl now no longer probes for C<d_u32align>, defaulting to C<define>
298on all platforms. This check was error prone when it was done, which
299was on 32-bit platforms only. [perl #133495]
06bfb2b1 300
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301=back
302
303=head1 Testing
304
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305XXX Any significant changes to the testing of a freshly built perl should be
306listed here. Changes which create B<new> files in F<t/> go here as do any
307large changes to the testing harness (e.g. when parallel testing was added).
308Changes to existing files in F<t/> aren't worth summarizing, although the bugs
309that they represent may be covered elsewhere.
310
311XXX If there were no significant test changes, say this:
312
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313Tests were added and changed to reflect the other additions and changes
314in this release.
315
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316XXX If instead there were significant changes, say this:
317
318Tests were added and changed to reflect the other additions and
319changes in this release. Furthermore, these significant changes were
320made:
321
322[ List each test improvement as an =item entry ]
323
324=over 4
325
326=item *
327
328XXX
329
330=back
331
dad02c36 332=head1 Platform Support
8424e368 333
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334XXX Any changes to platform support should be listed in the sections below.
335
336[ Within the sections, list each platform as an =item entry with specific
337changes as paragraphs below it. ]
338
339=head2 New Platforms
340
341XXX List any platforms that this version of perl compiles on, that previous
342versions did not. These will either be enabled by new files in the F<hints/>
343directories, or new subdirectories and F<README> files at the top level of the
344source tree.
345
346=over 4
347
348=item XXX-some-platform
349
350XXX
351
352=back
353
354=head2 Discontinued Platforms
355
356XXX List any platforms that this version of perl no longer compiles on.
fcbec156 357
fcbec156 358=over 4
061637ca 359
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360=item XXX-some-platform
361
362XXX
363
364=back
365
366=head2 Platform-Specific Notes
fcbec156 367
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368XXX List any changes for specific platforms. This could include configuration
369and compilation changes or changes in portability/compatibility. However,
370changes within modules for platforms should generally be listed in the
371L</Modules and Pragmata> section.
372
373=over 4
0076a047 374
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375=item XXX-some-platform
376
377XXX
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378
379=back
380
381=head1 Internal Changes
382
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383XXX Changes which affect the interface available to C<XS> code go here. Other
384significant internal changes for future core maintainers should be noted as
385well.
386
387[ List each change as an =item entry ]
388
fcbec156 389=over 4
061637ca 390
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391=item *
392
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393Added the C<<PL_curstackinfo->si_cxsubix>> field. This records the stack
394index of the most recently pushed sub/format/eval context. It is set and
395restored automatically by C<cx_pushsub()>, C<cx_popsub()> etc., but would
396need to be manually managed if you do any unusual manipulation of the
397context stack.
285db695 398
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399=item *
400
401Various macros dealing with character type classification and changing
402case where the input is encoded in UTF-8 now require an extra parameter
403to prevent potential reads beyond the end of the buffer. Use of these
404has generated a deprecation warning since 5.26. Details are in
405L<perldeprecation/In XS code, use of various macros dealing with UTF-8.>
406
9064626f 407=back
ed0cf058 408
9064626f 409=head1 Selected Bug Fixes
ed0cf058 410
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411XXX Important bug fixes in the core language are summarized here. Bug fixes in
412files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
413
414[ List each fix as an =item entry ]
415
9064626f 416=over 4
973ae088 417
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418=item *
419
74c14c97 420XXX
f7faf2ad 421
74c14c97 422=back
8714ff4f 423
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424=head1 Known Problems
425
426XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
427tests that had to be C<TODO>ed for the release would be noted here. Unfixed
428platform specific bugs also go here.
429
430[ List each fix as an =item entry ]
431
432=over 4
8714ff4f 433
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434=item *
435
74c14c97 436XXX
7118f704 437
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438=back
439
74c14c97 440=head1 Errata From Previous Releases
fcbec156 441
74c14c97 442=over 4
a3c77565 443
74c14c97 444=item *
fcbec156 445
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446XXX Add anything here that we forgot to add, or were mistaken about, in
447the perldelta of a previous release.
bd833cba 448
74c14c97 449=back
bd833cba 450
74c14c97 451=head1 Obituary
bd833cba 452
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453XXX If any significant core contributor or member of the CPAN community has
454died, add a short obituary here.
bd833cba 455
74c14c97 456=head1 Acknowledgements
bd833cba 457
74c14c97 458XXX Generate this with:
bd833cba 459
74c14c97 460 perl Porting/acknowledgements.pl v5.31.4..HEAD
8424e368 461
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462=head1 Reporting Bugs
463
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464If you find what you think is a bug, you might check the perl bug database
465at L<https://rt.perl.org/>. There may also be information at
71c89d21 466L<https://www.perl.org/>, the Perl Home Page.
44691e6f 467
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468If you believe you have an unreported bug, please run the L<perlbug> program
469included with your release. Be sure to trim your bug down to a tiny but
470sufficient test case. Your bug report, along with the output of C<perl -V>,
0e18d1c4 471will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
44691e6f 472
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473If the bug you are reporting has security implications which make it
474inappropriate to send to a publicly archived mailing list, then see
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475L<perlsec/SECURITY VULNERABILITY CONTACT INFORMATION>
476for details of how to report the issue.
44691e6f 477
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478=head1 Give Thanks
479
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480If you wish to thank the Perl 5 Porters for the work we had done in Perl 5,
481you can do so by running the C<perlthanks> program:
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482
483 perlthanks
484
485This will send an email to the Perl 5 Porters list with your show of thanks.
486
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487=head1 SEE ALSO
488
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489The F<Changes> file for an explanation of how to view exhaustive details on
490what changed.
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491
492The F<INSTALL> file for how to build Perl.
493
494The F<README> file for general stuff.
495
496The F<Artistic> and F<Copying> files for copyright information.
497
498=cut