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perldelta for adf9095d629bebb27169b0f3b03f75ee974da100
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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 v5.25.9
eabfc7bc 9
2cfe9b50 10=head1 DESCRIPTION
eabfc7bc 11
3ce6a296 12This document describes differences between the 5.25.8 release and the 5.25.9
4b8803f0 13release.
f3ed8cbf 14
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15If you are upgrading from an earlier release such as 5.25.7, first read
16L<perl5258delta>, which describes differences between 5.25.7 and 5.25.8.
17
18=head1 Notice
19
20XXX Any important notices here
8bbdbfcb 21
733dba2b 22=head1 Core Enhancements
ce6646d7 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
31
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 ]
37
38=head1 Incompatible Changes
39
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
43 If any exist, they are bugs, and we request that you submit a
44 report. See L</Reporting Bugs> below.
45
46[ List each incompatible change as a =head2 entry ]
47
48=head1 Deprecations
49
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50=head2 String delimiters that aren't stand-alone graphemes are now
51deprecated
52
53In order for Perl to eventually allow string delimiters to be Unicode
54grapheme clusters (which look like a single character, but may be
55a sequence of several ones), we have to stop allowing a single char
56delimiter that isn't a grapheme by itself. These are unlikely to exist
57in actual code, as they would typically display as attached to the
58character in front of them.
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59
60=head2 Module removals
61
62XXX Remove this section if inapplicable.
63
64The following modules will be removed from the core distribution in a
65future release, and will at that time need to be installed from CPAN.
66Distributions on CPAN which require these modules will need to list them as
67prerequisites.
68
69The core versions of these modules will now issue C<"deprecated">-category
70warnings to alert you to this fact. To silence these deprecation warnings,
71install the modules in question from CPAN.
72
73Note that these are (with rare exceptions) fine modules that you are encouraged
74to continue to use. Their disinclusion from core primarily hinges on their
75necessity to bootstrapping a fully functional, CPAN-capable Perl installation,
76not usually on concerns over their design.
eaed4a85 77
3ce6a296 78=over
eaed4a85 79
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80=item XXX
81
82XXX Note that deprecated modules should be listed here even if they are listed
83as an updated module in the L</Modules and Pragmata> section.
84
85=back
86
87[ List each other deprecation as a =head2 entry ]
eaed4a85 88
733dba2b 89=head1 Performance Enhancements
226eba01 90
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91XXX Changes which enhance performance without changing behaviour go here.
92There may well be none in a stable release.
8bbdbfcb 93
3ce6a296 94[ List each enhancement as a =item entry ]
8bbdbfcb 95
3ce6a296 96=over 4
8bbdbfcb 97
3ce6a296 98=item *
dd3d2a3f 99
3ce6a296 100XXX
dd3d2a3f 101
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102=back
103
733dba2b 104=head1 Modules and Pragmata
8bbdbfcb 105
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106XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
107go here. If Module::CoreList is updated, generate an initial draft of the
108following sections using F<Porting/corelist-perldelta.pl>. A paragraph summary
109for important changes should then be added by hand. In an ideal world,
110dual-life modules would have a F<Changes> file that could be cribbed.
111
112[ Within each section, list entries as a =item entry ]
113
114=head2 New Modules and Pragmata
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115
116=over 4
117
118=item *
119
3ce6a296 120XXX
8bbdbfcb 121
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122=back
123
124=head2 Updated Modules and Pragmata
ff10d69b 125
3ce6a296 126=over 4
ff10d69b 127
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128=item *
129
3ce6a296 130L<XXX> has been upgraded from version A.xx to B.yy.
8bbdbfcb 131
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132=item *
133
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134L<B::Xref> has been upgraded from version 1.05 to 1.06.
135
136=item *
137
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138L<Compress::Raw::Bzip2> has been upgraded from version 2.069 to 2.070.
139
140=item *
141
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142L<Compress::Raw::Zlib> has been upgraded from version 2.069 to 2.070.
143
144=item *
145
1146f1f7 146L<DB_File> has been upgraded from version 1.838 to 1.840.
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147
148=item *
149
1146f1f7 150L<Devel::SelfStubber> has been upgraded from version 1.05 to 1.06.
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151
152=item *
153
1146f1f7 154L<diagnostics> has been upgraded from version 1.35 to 1.36.
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155
156=item *
157
158L<DynaLoader> has been upgraded from version 1.40 to 1.41.
159
160=item *
161
162L<Errno> has been upgraded from version 1.27 to 1.28.
163
164=item *
165
166L<ExtUtils::Embed> has been upgraded from version 1.33 to 1.34.
167
168=item *
169
170L<I18N::LangTags> has been upgraded from version 0.41 to 0.42.
171
172=item *
173
174L<lib> has been upgraded from version 0.63 to 0.64.
175
176=item *
177
59aeb939 178L<Module::CoreList> has been upgraded from version 5.20161220 to 5.20170120.
d4151a23 179
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180=item *
181
4ee2b8db 182L<OS2::Process> has been upgraded from version 1.11 to 1.12.
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183
184=item *
185
186L<perl5db.pl> has been upgraded from version 1.50 to 1.51.
187
188=item *
189
74ef8fd9 190L<Storable> has been upgraded from version 2.59 to 2.61.
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191
192=item *
193
194L<Symbol> has been upgraded from version 1.07 to 1.08.
195
196=item *
197
198L<Term::ReadLine> has been upgraded from version 1.15 to 1.16.
199
200=item *
201
202L<Test> has been upgraded from version 1.29 to 1.30.
203
204=item *
205
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206L<threads::shared> has been upgraded from version 1.52 to 1.53.
207
208=item *
209
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210L<Unicode::UCD> has been upgraded from version 0.67 to 0.68.
211
212=item *
213
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214L<VMS::DCLsym> has been upgraded from version 1.07 to 1.08.
215
216=item *
217
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218L<XSLoader> has been upgraded from version 0.24 to 0.26.
219
3ce6a296 220=back
8bbdbfcb 221
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222=head2 Removed Modules and Pragmata
223
224=over 4
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225
226=item *
227
3ce6a296 228XXX
8bbdbfcb 229
3ce6a296 230=back
8bbdbfcb 231
3ce6a296 232=head1 Documentation
8bbdbfcb 233
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234XXX Changes to files in F<pod/> go here. Consider grouping entries by
235file and be sure to link to the appropriate page, e.g. L<perlfunc>.
8bbdbfcb 236
3ce6a296 237=head2 New Documentation
8bbdbfcb 238
3ce6a296 239XXX Changes which create B<new> files in F<pod/> go here.
8bbdbfcb 240
3ce6a296 241=head3 L<XXX>
8bbdbfcb 242
3ce6a296 243XXX Description of the purpose of the new file here
8bbdbfcb 244
3ce6a296 245=head2 Changes to Existing Documentation
8bbdbfcb 246
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247XXX Changes which significantly change existing files in F<pod/> go here.
248However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
249section.
250
251=head3 L<XXX>
8bbdbfcb 252
3ce6a296 253=over 4
8bbdbfcb 254
107db227 255=item *
8bbdbfcb 256
3ce6a296 257XXX Description of the change here
8bbdbfcb 258
3ce6a296 259=back
8bbdbfcb 260
3ce6a296 261=head1 Diagnostics
8bbdbfcb 262
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263The following additions or changes have been made to diagnostic output,
264including warnings and fatal error messages. For the complete list of
265diagnostic messages, see L<perldiag>.
266
267XXX New or changed warnings emitted by the core's C<C> code go here. Also
268include any changes in L<perldiag> that reconcile it to the C<C> code.
8c3f6b0b 269
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270=head2 New Diagnostics
271
272XXX Newly added diagnostic messages go under here, separated into New Errors
273and New Warnings
274
275=head3 New Errors
276
277=over 4
a09f502b 278
107db227 279=item *
2c4879e2 280
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281XXX L<message|perldiag/"message">
282
283=back
284
285=head3 New Warnings
286
287=over 4
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288
289=item *
290
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291XXX L<message|perldiag/"message">
292
293=back
294
295=head2 Changes to Existing Diagnostics
296
297XXX Changes (i.e. rewording) of diagnostic messages go here
298
299=over 4
bd5630ab 300
107db227 301=item *
2c4879e2 302
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303XXX Describe change here
304
305=back
306
307=head1 Utility Changes
308
309XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go here.
310Most of these are built within the directory F<utils>.
311
312[ List utility changes as a =head2 entry for each utility and =item
313entries for each change
314Use L<XXX> with program names to get proper documentation linking. ]
315
316=head2 L<XXX>
317
318=over 4
a09f502b 319
107db227 320=item *
8bbdbfcb 321
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322XXX
323
324=back
325
326=head1 Configuration and Compilation
327
328XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
329go here. Any other changes to the Perl build process should be listed here.
330However, any platform-specific changes should be listed in the
331L</Platform Support> section, instead.
332
333[ List changes as a =item entry ].
334
335=over 4
8bbdbfcb 336
107db227 337=item *
8bbdbfcb 338
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339XXX
340
341=back
342
343=head1 Testing
344
345XXX Any significant changes to the testing of a freshly built perl should be
346listed here. Changes which create B<new> files in F<t/> go here as do any
347large changes to the testing harness (e.g. when parallel testing was added).
348Changes to existing files in F<t/> aren't worth summarizing, although the bugs
349that they represent may be covered elsewhere.
350
351[ List each test improvement as a =item entry ]
352
353=over 4
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354
355=item *
356
3ce6a296 357XXX
07cfdfcc 358
262514fd 359=back
2c4879e2 360
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361=head1 Platform Support
362
363XXX Any changes to platform support should be listed in the sections below.
364
365[ Within the sections, list each platform as a =item entry with specific
366changes as paragraphs below it. ]
367
368=head2 New Platforms
369
370XXX List any platforms that this version of perl compiles on, that previous
371versions did not. These will either be enabled by new files in the F<hints/>
372directories, or new subdirectories and F<README> files at the top level of the
373source tree.
374
375=over 4
376
377=item XXX-some-platform
378
379XXX
380
381=back
382
383=head2 Discontinued Platforms
384
385XXX List any platforms that this version of perl no longer compiles on.
386
387=over 4
388
389=item XXX-some-platform
390
391XXX
392
393=back
394
395=head2 Platform-Specific Notes
396
397XXX List any changes for specific platforms. This could include configuration
398and compilation changes or changes in portability/compatibility. However,
399changes within modules for platforms should generally be listed in the
400L</Modules and Pragmata> section.
401
402=over 4
403
404=item XXX-some-platform
405
406XXX
407
408=back
409
410=head1 Internal Changes
411
412XXX Changes which affect the interface available to C<XS> code go here. Other
413significant internal changes for future core maintainers should be noted as
414well.
415
416[ List each change as a =item entry ]
a09f502b 417
733dba2b 418=over 4
a09f502b 419
a07f6112 420=item *
a09f502b 421
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422New versions of macros like C<isALPHA_utf8> and C<toLOWER_utf8> have
423been added, each with the
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424suffix C<_safe>, like C<isSPACE_utf8_safe>. These take an extra
425parameter, giving an upper limit of how far into the string it is safe
426to read. Using the old versions could cause attempts to read beyond the
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427end of the input buffer if the UTF-8 is not well-formed, and ther use
428now raises a deprecation warning. Details are at
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429L<perlapi/Character classification>.
430
431=item *
432
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433Calling macros like C<isALPHA_utf8> on malformed UTF-8 have issued a
434deprecation warning since Perl v5.18. They now die.
fa8ab374 435Similarly, macros like C<toLOWER_utf8> on malformed UTF-8 now die.
3ce6a296 436
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437=item *
438
439Calling the functions C<utf8n_to_uvchr> and its derivatives, while
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440passing a string length of 0 is now asserted against in DEBUGGING
441builds, and otherwise returns the Unicode REPLACEMENT CHARACTER. If
442you have nothing to decode, you shouldn't call the decode function.
d1f8d421 443
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444=item *
445
446The functions C<utf8n_to_uvchr> and its derivatives now return the
447Unicode REPLACEMENT CHARACTER if called with UTF-8 that has the overlong
448malformation, and that malformation is allowed by the input parameters.
449This malformation is where the UTF-8 looks valid syntactically, but
450there is a shorter sequence that yields the same code point. This has
451been forbidden since Unicode version 3.1.
452
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453=item *
454
455The functions C<utf8n_to_uvchr> and its derivatives now accept an input
456flag to allow the overflow malformation. This malformation is when the
457UTF-8 may be syntactically valid, but the code point it represents is
458not capable of being represented in the word length on the platform.
459What "allowed" means in this case is that the function doesn't return an
460error, and advances the parse pointer to beyond the UTF-8 in question,
461but it returns the Unicode REPLACEMENT CHARACTER as the value of the
462code point (since the real value is not representable).
463
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464=back
465
466=head1 Selected Bug Fixes
467
468XXX Important bug fixes in the core language are summarized here. Bug fixes in
469files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
470
471[ List each fix as a =item entry ]
472
473=over 4
a09f502b 474
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475=item *
476
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477Under C<use utf8>, the entire Perl program is now checked that the UTF-8
478is wellformed. This resolves [perl #126310].
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479
480=back
481
482=head1 Known Problems
483
484XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
485tests that had to be C<TODO>ed for the release would be noted here. Unfixed
486platform specific bugs also go here.
36cabe94 487
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488[ List each fix as a =item entry ]
489
490=over 4
491
492=item *
493
494XXX
36cabe94 495
a07f6112 496=back
7d897bd0 497
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498=head1 Errata From Previous Releases
499
500=over 4
8bbdbfcb 501
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502=item *
503
504XXX Add anything here that we forgot to add, or were mistaken about, in
505the perldelta of a previous release.
8bbdbfcb 506
3ce6a296 507=back
262514fd 508
3ce6a296 509=head1 Obituary
a6a32e96 510
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511XXX If any significant core contributor has died, we've added a short obituary
512here.
262514fd 513
3ce6a296 514=head1 Acknowledgements
226eba01 515
3ce6a296 516XXX Generate this with:
24528e8e 517
3ce6a296 518 perl Porting/acknowledgements.pl v5.25.5..HEAD
f5b73711 519
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520=head1 Reporting Bugs
521
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522If you find what you think is a bug, you might check the perl bug database
523at L<https://rt.perl.org/> . There may also be information at
4b8803f0 524L<http://www.perl.org/> , the Perl Home Page.
44691e6f 525
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526If you believe you have an unreported bug, please run the L<perlbug> program
527included with your release. Be sure to trim your bug down to a tiny but
528sufficient test case. Your bug report, along with the output of C<perl -V>,
529will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
44691e6f 530
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531If the bug you are reporting has security implications which make it
532inappropriate to send to a publicly archived mailing list, then see
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533L<perlsec/SECURITY VULNERABILITY CONTACT INFORMATION>
534for details of how to report the issue.
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535
536=head1 SEE ALSO
537
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538The F<Changes> file for an explanation of how to view exhaustive details on
539what changed.
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540
541The F<INSTALL> file for how to build Perl.
542
543The F<README> file for general stuff.
544
545The F<Artistic> and F<Copying> files for copyright information.
546
547=cut