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davem's perldelta entries for 5.25.9 so far
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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
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28=head2 New regular expression modifier C</xx>
29
30Specifying two C<x> characters to modify a regular expression pattern
31does everything that a single one does, but additionally TAB and SPACE
32characters within a bracketed character class are generally ignored and
33can be added to improve readability, like
34S<C</[ ^ A-Z d-f p-x ]/xx>>. Details are at
35L<perlre/E<sol>x and E<sol>xx>.
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36
37=head1 Security
38
39XXX Any security-related notices go here. In particular, any security
40vulnerabilities closed should be noted here rather than in the
41L</Selected Bug Fixes> section.
42
43[ List each security issue as a =head2 entry ]
44
45=head1 Incompatible Changes
46
47XXX For a release on a stable branch, this section aspires to be:
48
49 There are no changes intentionally incompatible with 5.XXX.XXX
50 If any exist, they are bugs, and we request that you submit a
51 report. See L</Reporting Bugs> below.
52
53[ List each incompatible change as a =head2 entry ]
54
55=head1 Deprecations
56
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57=head2 String delimiters that aren't stand-alone graphemes are now
58deprecated
59
60In order for Perl to eventually allow string delimiters to be Unicode
61grapheme clusters (which look like a single character, but may be
62a sequence of several ones), we have to stop allowing a single char
63delimiter that isn't a grapheme by itself. These are unlikely to exist
64in actual code, as they would typically display as attached to the
65character in front of them.
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66
67=head2 Module removals
68
69XXX Remove this section if inapplicable.
70
71The following modules will be removed from the core distribution in a
72future release, and will at that time need to be installed from CPAN.
73Distributions on CPAN which require these modules will need to list them as
74prerequisites.
75
76The core versions of these modules will now issue C<"deprecated">-category
77warnings to alert you to this fact. To silence these deprecation warnings,
78install the modules in question from CPAN.
79
80Note that these are (with rare exceptions) fine modules that you are encouraged
81to continue to use. Their disinclusion from core primarily hinges on their
82necessity to bootstrapping a fully functional, CPAN-capable Perl installation,
83not usually on concerns over their design.
eaed4a85 84
3ce6a296 85=over
eaed4a85 86
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87=item XXX
88
89XXX Note that deprecated modules should be listed here even if they are listed
90as an updated module in the L</Modules and Pragmata> section.
91
92=back
93
94[ List each other deprecation as a =head2 entry ]
eaed4a85 95
733dba2b 96=head1 Performance Enhancements
226eba01 97
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98XXX Changes which enhance performance without changing behaviour go here.
99There may well be none in a stable release.
8bbdbfcb 100
3ce6a296 101[ List each enhancement as a =item entry ]
8bbdbfcb 102
3ce6a296 103=over 4
8bbdbfcb 104
3ce6a296 105=item *
dd3d2a3f 106
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107A hash in boolean context is now sometimes faster, e.g.
108
109 if (!%h) { ... }
110
111This was already special-cased, but some cases were missed, and even the
112ones which weren't have been improved.
dd3d2a3f 113
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114=back
115
733dba2b 116=head1 Modules and Pragmata
8bbdbfcb 117
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118XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
119go here. If Module::CoreList is updated, generate an initial draft of the
120following sections using F<Porting/corelist-perldelta.pl>. A paragraph summary
121for important changes should then be added by hand. In an ideal world,
122dual-life modules would have a F<Changes> file that could be cribbed.
123
124[ Within each section, list entries as a =item entry ]
125
126=head2 New Modules and Pragmata
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127
128=over 4
129
130=item *
131
3ce6a296 132XXX
8bbdbfcb 133
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134=back
135
136=head2 Updated Modules and Pragmata
ff10d69b 137
3ce6a296 138=over 4
ff10d69b 139
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140=item *
141
3ce6a296 142L<XXX> has been upgraded from version A.xx to B.yy.
8bbdbfcb 143
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144=item *
145
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146L<re> has been upgraded from version 0.33 to 0.34;
147
148This adds support for the new L<C</xx>|perlre/E<sol>x and E<sol>xx>
149regular expression pattern modifier, and a change to the L<S<C<use re
150'strict'>>|re/'strict' mode> experimental feature. When S<C<re
151'strict'>> is enabled, a warning now will be generated for all
152unescaped uses of the two characters C<}> and C<]> in regular
153expression patterns (outside bracketed character classes) that are taken
154literally. This brings them more in line with the C<)> character which
155is always a metacharacter unless escaped. Being a metacharacter only
156sometimes, depending on action at a distance, can lead to silently
157having the pattern mean something quite different than was intended,
158which the S<C<re 'strict'>> mode is intended to minimize.
159
160=item *
161
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162L<B::Xref> has been upgraded from version 1.05 to 1.06.
163
164=item *
165
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166L<Compress::Raw::Bzip2> has been upgraded from version 2.069 to 2.070.
167
168=item *
169
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170L<Compress::Raw::Zlib> has been upgraded from version 2.069 to 2.070.
171
172=item *
173
1146f1f7 174L<DB_File> has been upgraded from version 1.838 to 1.840.
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175
176=item *
177
1146f1f7 178L<Devel::SelfStubber> has been upgraded from version 1.05 to 1.06.
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179
180=item *
181
1146f1f7 182L<diagnostics> has been upgraded from version 1.35 to 1.36.
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183
184=item *
185
186L<DynaLoader> has been upgraded from version 1.40 to 1.41.
187
188=item *
189
190L<Errno> has been upgraded from version 1.27 to 1.28.
191
192=item *
193
194L<ExtUtils::Embed> has been upgraded from version 1.33 to 1.34.
195
196=item *
197
198L<I18N::LangTags> has been upgraded from version 0.41 to 0.42.
199
200=item *
201
202L<lib> has been upgraded from version 0.63 to 0.64.
203
204=item *
205
59aeb939 206L<Module::CoreList> has been upgraded from version 5.20161220 to 5.20170120.
d4151a23 207
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208=item *
209
4ee2b8db 210L<OS2::Process> has been upgraded from version 1.11 to 1.12.
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211
212=item *
213
214L<perl5db.pl> has been upgraded from version 1.50 to 1.51.
215
216=item *
217
74ef8fd9 218L<Storable> has been upgraded from version 2.59 to 2.61.
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219
220=item *
221
222L<Symbol> has been upgraded from version 1.07 to 1.08.
223
224=item *
225
226L<Term::ReadLine> has been upgraded from version 1.15 to 1.16.
227
228=item *
229
230L<Test> has been upgraded from version 1.29 to 1.30.
231
232=item *
233
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234L<threads::shared> has been upgraded from version 1.52 to 1.53.
235
236=item *
237
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238L<Unicode::UCD> has been upgraded from version 0.67 to 0.68.
239
240=item *
241
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242L<VMS::DCLsym> has been upgraded from version 1.07 to 1.08.
243
244=item *
245
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246L<XSLoader> has been upgraded from version 0.24 to 0.26.
247
3ce6a296 248=back
8bbdbfcb 249
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250=head2 Removed Modules and Pragmata
251
252=over 4
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253
254=item *
255
3ce6a296 256XXX
8bbdbfcb 257
3ce6a296 258=back
8bbdbfcb 259
3ce6a296 260=head1 Documentation
8bbdbfcb 261
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262XXX Changes to files in F<pod/> go here. Consider grouping entries by
263file and be sure to link to the appropriate page, e.g. L<perlfunc>.
8bbdbfcb 264
3ce6a296 265=head2 New Documentation
8bbdbfcb 266
3ce6a296 267XXX Changes which create B<new> files in F<pod/> go here.
8bbdbfcb 268
3ce6a296 269=head3 L<XXX>
8bbdbfcb 270
3ce6a296 271XXX Description of the purpose of the new file here
8bbdbfcb 272
3ce6a296 273=head2 Changes to Existing Documentation
8bbdbfcb 274
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275XXX Changes which significantly change existing files in F<pod/> go here.
276However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
277section.
278
279=head3 L<XXX>
8bbdbfcb 280
3ce6a296 281=over 4
8bbdbfcb 282
107db227 283=item *
8bbdbfcb 284
3ce6a296 285XXX Description of the change here
8bbdbfcb 286
3ce6a296 287=back
8bbdbfcb 288
3ce6a296 289=head1 Diagnostics
8bbdbfcb 290
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291The following additions or changes have been made to diagnostic output,
292including warnings and fatal error messages. For the complete list of
293diagnostic messages, see L<perldiag>.
294
295XXX New or changed warnings emitted by the core's C<C> code go here. Also
296include any changes in L<perldiag> that reconcile it to the C<C> code.
8c3f6b0b 297
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298=head2 New Diagnostics
299
300XXX Newly added diagnostic messages go under here, separated into New Errors
301and New Warnings
302
303=head3 New Errors
304
305=over 4
a09f502b 306
107db227 307=item *
2c4879e2 308
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309XXX L<message|perldiag/"message">
310
311=back
312
313=head3 New Warnings
314
315=over 4
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316
317=item *
318
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319XXX L<message|perldiag/"message">
320
321=back
322
323=head2 Changes to Existing Diagnostics
324
57b3a6b6 325As of Perl 5.25.9, all new deprecations will come with a version in
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326which the feature will disappear. And with a few exceptions, most
327existing deprecations will state when they'll disappear. As such, most
328deprecation messages have changed.
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329
330=over 4
bd5630ab 331
107db227 332=item *
2c4879e2 333
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334Attribute "locked" is deprecated, and will disappear in Perl 5.28
335
336=item *
337
338Attribute "unique" is deprecated, and will disappear in Perl 5.28
339
340=item *
341
342"\c%c" is more clearly written simply as "%s". This will be a fatal error
343in Perl 5.28
344
345=item *
346
347Constants from lexical variables potentially modified elsewhere are
348deprecated. This will not be allowed in Perl 5.32
349
350=item *
351
352Deprecated use of my() in false conditional. This will be a fatal error
353in Perl 5.30
354
355=item *
356
357dump() better written as CORE::dump(). dump() will no longer be available
358in Perl 5.30
359
360=item *
361
362${^ENCODING} is no longer supported. Its use will be fatal in Perl 5.28
363
364=item *
365
366File::Glob::glob() will disappear in perl 5.30. Use File::Glob::bsd_glob()
367instead.
368
369=item *
370
371%s() is deprecated on :utf8 handles. This will be a fatal error in Perl 5.30
372
373=item *
374
375$* is no longer supported. Its use will be fatal in Perl 5.30
376
377=item *
378
379$* is no longer supported. Its use will be fatal in Perl 5.30
380
381=item *
382
383Opening dirhandle %s also as a file. This will be a fatal error in Perl 5.28
384
385=item *
386
387Opening filehandle %s also as a directory. This will be a fatal
388error in Perl 5.28
389
390=item *
391
392Setting $/ to a reference to %s as a form of slurp is deprecated,
393treating as undef. This will be fatal in Perl 5.28
394
395=item *
396
397Unescaped left brace in regex is deprecated here (and will be fatal
398in Perl 5.30), passed through in regex; marked by S<<-- HERE> in m/%s/
399
400=item *
401
402Unknown charname '' is deprecated. Its use will be fatal in Perl 5.28
403
404=item *
405
406Use of bare << to mean <<"" is deprecated. Its use will be fatal in Perl 5.28
407
408=item *
409
410Use of code point 0x%s is deprecated; the permissible max is 0x%s.
411This will be fatal in Perl 5.28
412
413=item *
414
415Use of comma-less variable list is deprecated. Its use will be fatal
416in Perl 5.28
417
418=item *
419
420Use of inherited AUTOLOAD for non-method %s() is deprecated. This
421will be fatal in Perl 5.28
422
423=item *
424
425Use of strings with code points over 0xFF as arguments to %s operator
426is deprecated. This will be a fatal error in Perl 5.28
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427
428=back
429
430=head1 Utility Changes
431
432XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go here.
433Most of these are built within the directory F<utils>.
434
435[ List utility changes as a =head2 entry for each utility and =item
436entries for each change
437Use L<XXX> with program names to get proper documentation linking. ]
438
439=head2 L<XXX>
440
441=over 4
a09f502b 442
107db227 443=item *
8bbdbfcb 444
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445XXX
446
447=back
448
449=head1 Configuration and Compilation
450
451XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
452go here. Any other changes to the Perl build process should be listed here.
453However, any platform-specific changes should be listed in the
454L</Platform Support> section, instead.
455
456[ List changes as a =item entry ].
457
458=over 4
8bbdbfcb 459
107db227 460=item *
8bbdbfcb 461
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462The C<dtrace> build process has further changes:
463
464=over
465
466=item *
467
468If the C<-xnolibs> is available, use that so a F<dtrace> perl can be
469built within a FreeBSD jail.
470
471=item *
472
473On systems that build a dtrace object file (FreeBSD, Solaris and
474SystemTap's dtrace emulation), copy the input objects to a separate
475directory and process them there, and use those objects in the link,
476since C<dtrace -G> also modifies these objects.
477
478=item *
479
480Add libelf to the build on FreeBSD 10.x, since dtrace adds references
481to libelf symbols.
482
483=item *
484
485Generate a dummy dtrace_main.o if C<dtrace -G> fails to build it. A
486default build on Solaris generates probes from the unused inline
487functions, while they don't on FreeBSD, which causes C<dtrace -G> to
488fail.
489
490=back
491
492[perl #130108]
3ce6a296 493
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494=item *
495
496You can now disable perl's use of the PERL_HASH_SEED and
497PERL_PERTURB_KEYS environment variables by configureing perl with
498C<-Accflags=NO_PERL_HASH_ENV>.
499
500=item *
501
502You can now disable perl's use of the PERL_HASH_SEED_DEBUG environment
503variable by configuring perl with
504C<-Accflags=-DNO_PERL_HASH_SEED_DEBUG>.
505
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506=back
507
508=head1 Testing
509
510XXX Any significant changes to the testing of a freshly built perl should be
511listed here. Changes which create B<new> files in F<t/> go here as do any
512large changes to the testing harness (e.g. when parallel testing was added).
513Changes to existing files in F<t/> aren't worth summarizing, although the bugs
514that they represent may be covered elsewhere.
515
516[ List each test improvement as a =item entry ]
517
518=over 4
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519
520=item *
521
3ce6a296 522XXX
07cfdfcc 523
262514fd 524=back
2c4879e2 525
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526=head1 Platform Support
527
528XXX Any changes to platform support should be listed in the sections below.
529
530[ Within the sections, list each platform as a =item entry with specific
531changes as paragraphs below it. ]
532
533=head2 New Platforms
534
535XXX List any platforms that this version of perl compiles on, that previous
536versions did not. These will either be enabled by new files in the F<hints/>
537directories, or new subdirectories and F<README> files at the top level of the
538source tree.
539
540=over 4
541
542=item XXX-some-platform
543
544XXX
545
546=back
547
548=head2 Discontinued Platforms
549
550XXX List any platforms that this version of perl no longer compiles on.
551
552=over 4
553
554=item XXX-some-platform
555
556XXX
557
558=back
559
560=head2 Platform-Specific Notes
561
562XXX List any changes for specific platforms. This could include configuration
563and compilation changes or changes in portability/compatibility. However,
564changes within modules for platforms should generally be listed in the
565L</Modules and Pragmata> section.
566
567=over 4
568
569=item XXX-some-platform
570
571XXX
572
573=back
574
575=head1 Internal Changes
576
577XXX Changes which affect the interface available to C<XS> code go here. Other
578significant internal changes for future core maintainers should be noted as
579well.
580
581[ List each change as a =item entry ]
a09f502b 582
733dba2b 583=over 4
a09f502b 584
a07f6112 585=item *
a09f502b 586
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587New versions of macros like C<isALPHA_utf8> and C<toLOWER_utf8> have
588been added, each with the
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589suffix C<_safe>, like C<isSPACE_utf8_safe>. These take an extra
590parameter, giving an upper limit of how far into the string it is safe
591to read. Using the old versions could cause attempts to read beyond the
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592end of the input buffer if the UTF-8 is not well-formed, and ther use
593now raises a deprecation warning. Details are at
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594L<perlapi/Character classification>.
595
596=item *
597
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598Calling macros like C<isALPHA_utf8> on malformed UTF-8 have issued a
599deprecation warning since Perl v5.18. They now die.
fa8ab374 600Similarly, macros like C<toLOWER_utf8> on malformed UTF-8 now die.
3ce6a296 601
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602=item *
603
604Calling the functions C<utf8n_to_uvchr> and its derivatives, while
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605passing a string length of 0 is now asserted against in DEBUGGING
606builds, and otherwise returns the Unicode REPLACEMENT CHARACTER. If
607you have nothing to decode, you shouldn't call the decode function.
d1f8d421 608
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609=item *
610
611The functions C<utf8n_to_uvchr> and its derivatives now return the
612Unicode REPLACEMENT CHARACTER if called with UTF-8 that has the overlong
613malformation, and that malformation is allowed by the input parameters.
614This malformation is where the UTF-8 looks valid syntactically, but
615there is a shorter sequence that yields the same code point. This has
616been forbidden since Unicode version 3.1.
617
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618=item *
619
620The functions C<utf8n_to_uvchr> and its derivatives now accept an input
621flag to allow the overflow malformation. This malformation is when the
622UTF-8 may be syntactically valid, but the code point it represents is
623not capable of being represented in the word length on the platform.
624What "allowed" means in this case is that the function doesn't return an
625error, and advances the parse pointer to beyond the UTF-8 in question,
626but it returns the Unicode REPLACEMENT CHARACTER as the value of the
627code point (since the real value is not representable).
628
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629=back
630
631=head1 Selected Bug Fixes
632
633XXX Important bug fixes in the core language are summarized here. Bug fixes in
634files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
635
636[ List each fix as a =item entry ]
637
638=over 4
a09f502b 639
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640=item *
641
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642Under C<use utf8>, the entire Perl program is now checked that the UTF-8
643is wellformed. This resolves [perl #126310].
3ce6a296 644
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645=item *
646
647The range operator C<..> on strings now handles its arguments correctly when in
648the scope of the L<< C<unicode_strings>|feature/"The 'unicode_strings' feature" >>
649feature. The previous behaviour was sufficiently unexpected that we believe no
650correct program could have made use of it.
651
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652=item *
653
654The S<split> operator did not ensure enough space was allocated for
655its return value in scalar context. It could then write a single
656pointer immediately beyond the end of the memory block allocated for
657the stack. [perl #130262]
658
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659=item *
660
661Using a large code point with the C<W> pack template character with
662the current output position aligned at just the right point could
663cause a write a single zero byte immediately beyond the end of an
664allocated buffer. [perl #129149]
665
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666=back
667
668=head1 Known Problems
669
670XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
671tests that had to be C<TODO>ed for the release would be noted here. Unfixed
672platform specific bugs also go here.
36cabe94 673
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674[ List each fix as a =item entry ]
675
676=over 4
677
678=item *
679
680XXX
36cabe94 681
a07f6112 682=back
7d897bd0 683
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684=head1 Errata From Previous Releases
685
686=over 4
8bbdbfcb 687
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688=item *
689
690XXX Add anything here that we forgot to add, or were mistaken about, in
691the perldelta of a previous release.
8bbdbfcb 692
3ce6a296 693=back
262514fd 694
3ce6a296 695=head1 Obituary
a6a32e96 696
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697XXX If any significant core contributor has died, we've added a short obituary
698here.
262514fd 699
3ce6a296 700=head1 Acknowledgements
226eba01 701
3ce6a296 702XXX Generate this with:
24528e8e 703
3ce6a296 704 perl Porting/acknowledgements.pl v5.25.5..HEAD
f5b73711 705
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706=head1 Reporting Bugs
707
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708If you find what you think is a bug, you might check the perl bug database
709at L<https://rt.perl.org/> . There may also be information at
4b8803f0 710L<http://www.perl.org/> , the Perl Home Page.
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712If you believe you have an unreported bug, please run the L<perlbug> program
713included with your release. Be sure to trim your bug down to a tiny but
714sufficient test case. Your bug report, along with the output of C<perl -V>,
715will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
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717If the bug you are reporting has security implications which make it
718inappropriate to send to a publicly archived mailing list, then see
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719L<perlsec/SECURITY VULNERABILITY CONTACT INFORMATION>
720for details of how to report the issue.
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721
722=head1 SEE ALSO
723
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724The F<Changes> file for an explanation of how to view exhaustive details on
725what changed.
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726
727The F<INSTALL> file for how to build Perl.
728
729The F<README> file for general stuff.
730
731The F<Artistic> and F<Copying> files for copyright information.
732
733=cut