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perldelta - Add links for rt.perl.org bugs
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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 v5.21.4
c68523cb 9
238894db 10=head1 DESCRIPTION
c68523cb 11
39c4a6cf 12This document describes differences between the 5.21.3 release and the 5.21.4
238894db 13release.
c68523cb 14
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15If you are upgrading from an earlier release such as 5.21.2, first read
16L<perl5213delta>, which describes differences between 5.21.2 and 5.21.3.
7065301c 17
39c4a6cf 18=head1 Notice
7e957246 19
39c4a6cf 20XXX Any important notices here
7e957246 21
39c4a6cf 22=head1 Core Enhancements
f88f10f5 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.
21f3b41e 27
39c4a6cf 28[ List each enhancement as a =head2 entry ]
f88f10f5 29
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30=head2 Infinity and NaN (not-a-number) handling improved
31
32Floating point values are able to hold the special values infinity
33(also -infinity), and NaN (not-a-number). Now we more robustly recognize
34and propagate the value in computations, and on output normalize them
35to C<Inf> and C<NaN>.
36
019bf663 37See also the L<POSIX> enhancements.
5b319db8 38
0346c3a9 39=head1 Security
7e957246 40
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41XXX Any security-related notices go here. In particular, any security
42vulnerabilities closed should be noted here rather than in the
43L</Selected Bug Fixes> section.
13900f93 44
39c4a6cf 45[ List each security issue as a =head2 entry ]
8bdb3f93 46
13900f93 47=head1 Incompatible Changes
8bdb3f93 48
39c4a6cf 49XXX For a release on a stable branch, this section aspires to be:
1178d2cf 50
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51 There are no changes intentionally incompatible with 5.XXX.XXX
52 If any exist, they are bugs, and we request that you submit a
53 report. See L</Reporting Bugs> below.
1178d2cf 54
39c4a6cf 55[ List each incompatible change as a =head2 entry ]
f6f3144e 56
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57=head2 Changes to the C<*> prototype
58
59The C<*> character in a subroutine's prototype used to allow barewords
60to take precedence over most, but not all subroutines. It was never
61consistent and exhibited buggy behaviour.
62
63Now it has been changed, so subroutines always take precedence over
64barewords, which brings it into conformity with similarly prototyped
65built-in functions:
66
67 sub splat($) { ... }
68 sub foo { ... }
69 splat(foo); # now always splat(foo())
70 splat(bar); # still splat('bar') as before
71 close(foo); # close(foo())
72 close(bar); # close('bar')
73
39c4a6cf 74=head1 Deprecations
7065301c 75
39c4a6cf 76XXX Any deprecated features, syntax, modules etc. should be listed here.
7065301c 77
39c4a6cf 78=head2 Module removals
b3e82ed1 79
39c4a6cf 80XXX Remove this section if inapplicable.
ca58223b 81
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82The following modules will be removed from the core distribution in a
83future release, and will at that time need to be installed from CPAN.
84Distributions on CPAN which require these modules will need to list them as
85prerequisites.
ca58223b 86
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87The core versions of these modules will now issue C<"deprecated">-category
88warnings to alert you to this fact. To silence these deprecation warnings,
89install the modules in question from CPAN.
23b03637 90
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91Note that these are (with rare exceptions) fine modules that you are encouraged
92to continue to use. Their disinclusion from core primarily hinges on their
93necessity to bootstrapping a fully functional, CPAN-capable Perl installation,
94not usually on concerns over their design.
23b03637 95
39c4a6cf 96=over
85e8fb10 97
39c4a6cf 98=item XXX
85e8fb10 99
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100XXX Note that deprecated modules should be listed here even if they are listed
101as an updated module in the L</Modules and Pragmata> section.
134f90c2 102
39c4a6cf 103=back
134f90c2 104
39c4a6cf 105[ List each other deprecation as a =head2 entry ]
ff433f2d 106
39c4a6cf 107=head1 Performance Enhancements
ff433f2d 108
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109XXX Changes which enhance performance without changing behaviour go here.
110There may well be none in a stable release.
134f90c2 111
39c4a6cf 112[ List each enhancement as a =item entry ]
134f90c2 113
39c4a6cf 114=over 4
7d19f6a1 115
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116=item *
117
4f81ab9c 118Subroutines with an empty prototype and bodies containing just C<undef> are
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119now eligible for inlining.
120L<[perl #122728]|https://rt.perl.org/Ticket/Display.html?id=122728>
55e8b286 121
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122=item *
123
124Subroutines in packages no longer need to carry typeglobs around with them.
125Declaring a subroutine will now put a simple sub reference in the stash if
126possible, saving memory. The typeglobs still notionally exist, so
127accessing them will cause the subroutine reference to be upgraded to a
128typeglob. This optimisation does not currently apply to XSUBs or exported
129subroutines, and method calls will undo it, since they cache things in
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130typeglobs.
131L<[perl #120441]|https://rt.perl.org/Ticket/Display.html?id=120441>
07600c14 132
39c4a6cf 133=back
55e8b286 134
39c4a6cf 135=head1 Modules and Pragmata
d99849ae 136
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137XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
138go here. If Module::CoreList is updated, generate an initial draft of the
139following sections using F<Porting/corelist-perldelta.pl>. A paragraph summary
140for important changes should then be added by hand. In an ideal world,
141dual-life modules would have a F<Changes> file that could be cribbed.
d99849ae 142
39c4a6cf 143[ Within each section, list entries as a =item entry ]
ff433f2d 144
39c4a6cf 145=head2 New Modules and Pragmata
ff433f2d 146
39c4a6cf 147=over 4
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148
149=item *
150
39c4a6cf 151XXX
0bb39c26 152
39c4a6cf 153=back
0bb39c26 154
39c4a6cf 155=head2 Updated Modules and Pragmata
9c97a342 156
39c4a6cf 157=over 4
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158
159=item *
160
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161L<Archive::Tar> has been upgraded from version 2.00 to 2.02.
162
163Tests can now be run in parallel.
164
165=item *
166
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167L<Attribute::Handlers> has been upgraded from version 0.96 to 0.97.
168
169=item *
170
171L<attributes> has been upgraded from version 0.22 to 0.23.
172
173=item *
174
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175L<B> has been upgraded from version 1.50 to 1.51.
176
177It provides a new C<B::safename> function, based on the existing
178C<< B::GV->SAFENAME >>, that converts "\cOPEN" to "^OPEN".
6ab3666b 179
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180=item *
181
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182L<B::Concise> has been upgraded from version 0.992 to 0.993.
183
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184=item *
185
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186L<B::Deparse> has been upgraded from version 1.27 to 1.28.
187
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188It now deparses C<our(I<LIST>)> and typed lexical (C<my Dog $spot>) correctly.
189
190=item *
191
192L<bignum> has been upgraded from version 0.37 to 0.38.
193
194=item *
195
196L<constant> has been upgraded from version 1.31 to 1.32.
197
198It now accepts fully-qualified constant names, allowing constants to be defined
199in packages other than the caller.
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200
201=item *
202
608e531f 203L<CPAN::Meta::Requirements> has been upgraded from version 2.126 to 2.128.
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204
205=item *
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206
207L<Data::Dumper> has been upgraded from version 2.152 to 2.154.
208
209=item *
74d5bfab 210
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211L<experimental> has been upgraded from version 0.008 to 0.010.
212
213=item *
214
215L<ExtUtils::CBuilder> has been upgraded from version 0.280217 to 0.280219.
8f5ad91b 216L<[perl #122675]|https://rt.perl.org/Ticket/Display.html?id=122675>
74d5bfab 217
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218=item *
219
8435afd1 220L<ExtUtils::Install> has been upgraded from version 1.68 to 2.04.
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221
222=item *
223
8435afd1 224L<ExtUtils::Manifest> has been upgraded from version 1.65 to 1.68.
8f5ad91b 225L<[perl #122415]|https://rt.perl.org/Ticket/Display.html?id=122415>
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226
227=item *
228
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229L<File::Find> has been upgraded from version 1.27 to 1.28.
230
231C<find()> and C<finddepth()> will now warn if passed inappropriate or
232misspelled options.
233
234=item *
235
236L<Getopt::Std> has been upgraded from version 1.10 to 1.11.
237
238=item *
239
8435afd1 240L<HTTP::Tiny> has been upgraded from version 0.047 to 0.049.
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241
242=item *
243
8435afd1 244L<IO> has been upgraded from version 1.33 to 1.34.
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245
246=item *
247
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248L<IO::Socket::IP> has been upgraded from version 0.31 to 0.32.
249
250=item *
d0ab07ee 251
8435afd1 252L<Locale::Codes> has been upgraded from version 3.31 to 3.32.
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253
254=item *
255
256L<Math::BigInt> has been upgraded from version 1.9996 to 1.9997.
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257
258=item *
259
260L<Module::CoreList> has been upgraded from version 5.021003 to 5.20140915.
261
262=item *
263
264L<overload> has been upgraded from version 1.22 to 1.23.
265
266=item *
267
268PathTools has been upgraded from version 3.49 to 3.50.
5b319db8 269
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270=item *
271
272L<Pod::Perldoc> has been upgraded from version 3.23 to 3.24.
273
274=item *
275
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276L<POSIX> has been upgraded from version 1.42 to 1.43.
277
278The C99 math functions and constants (for example acosh, round, M_E, M_PI) have
279been added.
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280
281=item *
282
8435afd1 283Scalar-List-Utils has been upgraded from version 1.39 to 1.41.
d0ab07ee 284
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285=item *
286
287L<Term::ReadLine> has been upgraded from version 1.14 to 1.15.
288
289=item *
290
291L<Test::Harness> has been upgraded from version 3.32 to 3.33.
292
293=item *
294
295L<Test::Simple> has been upgraded from version 1.001003 to 1.001006.
bfc60ea2 296
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297=item *
298
299L<threads> has been upgraded from version 1.95 to 1.96.
300
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301=item *
302
303L<Time::Piece> has been upgraded from version 1.27 to 1.29.
304
305=item *
306
307L<version> has been upgraded from version 0.9908 to 0.9909.
308
39c4a6cf 309=back
9c97a342 310
39c4a6cf 311=head2 Removed Modules and Pragmata
d99849ae 312
39c4a6cf 313=over 4
d99849ae 314
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315=item *
316
39c4a6cf 317XXX
ff433f2d 318
13900f93 319=back
aac7f82f 320
13900f93 321=head1 Documentation
aac7f82f 322
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323XXX Changes to files in F<pod/> go here. Consider grouping entries by
324file and be sure to link to the appropriate page, e.g. L<perlfunc>.
6d9b7c7c 325
39c4a6cf 326=head2 New Documentation
2a395b86 327
39c4a6cf 328XXX Changes which create B<new> files in F<pod/> go here.
2a395b86 329
39c4a6cf 330=head3 L<XXX>
2a395b86 331
39c4a6cf 332XXX Description of the purpose of the new file here
2a395b86 333
39c4a6cf 334=head2 Changes to Existing Documentation
2a395b86 335
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336XXX Changes which significantly change existing files in F<pod/> go here.
337However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
338section.
339
8435afd1 340=head3 L<perlsyn>
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341
342=over 4
343
344=item *
345
8435afd1 346An ambiguity in the documentation of the Ellipsis statement has
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347been corrected.
348L<[perl #122661]|https://rt.perl.org/Ticket/Display.html?id=122661>
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349
350=back
351
352=head3 L<perlxs>
353
354=over 4
2a395b86 355
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356=item *
357
8435afd1 358Added a discussion of locale issues in XS code.
12d22d1f 359
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360=back
361
39c4a6cf 362=head1 Diagnostics
2a395b86 363
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364The following additions or changes have been made to diagnostic output,
365including warnings and fatal error messages. For the complete list of
366diagnostic messages, see L<perldiag>.
2a395b86 367
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368XXX New or changed warnings emitted by the core's C<C> code go here. Also
369include any changes in L<perldiag> that reconcile it to the C<C> code.
2a395b86 370
39c4a6cf 371=head2 New Diagnostics
0f4a583b 372
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373XXX Newly added diagnostic messages go under here, separated into New Errors
374and New Warnings
2a395b86 375
39c4a6cf 376=head3 New Errors
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377
378=over 4
379
380=item *
381
39c4a6cf 382XXX L<message|perldiag/"message">
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383
384=back
385
39c4a6cf 386=head3 New Warnings
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387
388=over 4
389
390=item *
391
39c4a6cf 392XXX L<message|perldiag/"message">
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393
394=back
6d9b7c7c 395
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396=head2 Changes to Existing Diagnostics
397
398XXX Changes (i.e. rewording) of diagnostic messages go here
7f55cec0 399
13900f93 400=over 4
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401
402=item *
403
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404L<Global symbol "%s" requires explicit package name|perldiag/Global symbol "%s" requires explicit package name (did you forget to declare "my %s"?)>
405
406This message has had '(did you forget to declare "my %s"?)' appended to it,
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407to make it more helpful to new Perl programmers.
408L<[perl #121638]|https://rt.perl.org/Ticket/Display.html?id=121638>
aac7f82f 409
13900f93 410=back
aac7f82f 411
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412=head2 Diagnostic Removals
413
414=over 4
415
416=item *
417
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418"Constant is not a FOO reference"
419
420Compile-time checking of constant dereferencing (e.g.,
421C<< my_constant->() >>) has been removed, since it was not taking
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422overloading into account.
423L<[perl #69456]|https://rt.perl.org/Ticket/Display.html?id=69456>
424L<[perl #122607]|https://rt.perl.org/Ticket/Display.html?id=122607>
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425
426=item *
427
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428The warning "Ambiguous use of -foo resolved as -&foo()" has been removed.
429There is actually no ambiguity here, and this impedes the use of negated
430constants; e.g., C<-Inf>.
431
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432=item *
433
434The little-known C<my Class $var> syntax (see L<fields> and L<attributes>)
435could get confused in the scope of C<use utf8> if C<Class> were a constant
436whose value contained Latin-1 characters.
437
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438=back
439
39c4a6cf 440=head1 Utility Changes
091fed7c 441
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442XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go here.
443Most of these are built within the directory F<utils>.
902c1f75 444
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445[ List utility changes as a =head2 entry for each utility and =item
446entries for each change
447Use L<XXX> with program names to get proper documentation linking. ]
2901561d 448
39c4a6cf 449=head2 L<XXX>
4594cf53 450
13900f93 451=over 4
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452
453=item *
454
39c4a6cf 455XXX
a1d26ccd 456
39c4a6cf 457=back
a1d26ccd 458
39c4a6cf 459=head1 Configuration and Compilation
7065301c 460
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461XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
462go here. Any other changes to the Perl build process should be listed here.
463However, any platform-specific changes should be listed in the
464L</Platform Support> section, instead.
58f25ac1 465
39c4a6cf 466[ List changes as a =item entry ].
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467
468=over 4
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469
470=item *
471
39c4a6cf 472XXX
a5873648 473
39c4a6cf 474=back
a5873648 475
39c4a6cf 476=head1 Testing
a5873648 477
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478XXX Any significant changes to the testing of a freshly built perl should be
479listed here. Changes which create B<new> files in F<t/> go here as do any
480large changes to the testing harness (e.g. when parallel testing was added).
481Changes to existing files in F<t/> aren't worth summarizing, although the bugs
482that they represent may be covered elsewhere.
a5873648 483
39c4a6cf 484[ List each test improvement as a =item entry ]
a5873648 485
39c4a6cf 486=over 4
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487
488=item *
489
39c4a6cf 490XXX
a5873648 491
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492=back
493
39c4a6cf 494=head1 Platform Support
b10906fb 495
39c4a6cf 496XXX Any changes to platform support should be listed in the sections below.
b10906fb 497
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498[ Within the sections, list each platform as a =item entry with specific
499changes as paragraphs below it. ]
b10906fb 500
39c4a6cf 501=head2 New Platforms
b10906fb 502
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503XXX List any platforms that this version of perl compiles on, that previous
504versions did not. These will either be enabled by new files in the F<hints/>
505directories, or new subdirectories and F<README> files at the top level of the
506source tree.
13900f93 507
7065301c 508=over 4
24a38d90 509
39c4a6cf 510=item XXX-some-platform
24a38d90 511
39c4a6cf 512XXX
bb076206 513
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514=back
515
39c4a6cf 516=head2 Discontinued Platforms
097675bf 517
39c4a6cf 518XXX List any platforms that this version of perl no longer compiles on.
b3211734 519
6e97d65d 520=over 4
b3211734 521
39c4a6cf 522=item XXX-some-platform
7065301c 523
39c4a6cf 524XXX
13900f93 525
39c4a6cf 526=back
7d0ccdba 527
39c4a6cf 528=head2 Platform-Specific Notes
7d0ccdba 529
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530XXX List any changes for specific platforms. This could include configuration
531and compilation changes or changes in portability/compatibility. However,
532changes within modules for platforms should generally be listed in the
533L</Modules and Pragmata> section.
6e97d65d 534
39c4a6cf 535=over 4
6e97d65d 536
39c4a6cf 537=item XXX-some-platform
6e97d65d 538
39c4a6cf 539XXX
7d0ccdba 540
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541=back
542
543=head1 Internal Changes
544
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545XXX Changes which affect the interface available to C<XS> code go here. Other
546significant internal changes for future core maintainers should be noted as
547well.
c9fcb674 548
39c4a6cf 549[ List each change as a =item entry ]
a835cd47 550
39c4a6cf 551=over 4
c1284011 552
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553=item *
554
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555C<save_re_context> no longer does anything and has been moved to
556F<mathoms.c>.
1c43698b 557
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558=item *
559
560C<cv_name> is a new API function that can be passed a CV or GV. It returns
561an SV containing the name of the subroutine for use in diagnostics.
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562L<[perl #116735]|https://rt.perl.org/Ticket/Display.html?id=116735>
563L<[perl #120441]|https://rt.perl.org/Ticket/Display.html?id=120441>
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564
565=item *
566
567C<cv_set_call_checker_flags> is a new API function that works like
568C<cv_set_call_checker>, except that it allows the caller to specify whether
569the call checker requires a full GV for reporting the subroutine's name, or
570whether it could be passed a CV instead. Whatever value is passed will be
571acceptable to C<cv_name>. C<cv_set_call_checker> guarantees there will be
572a GV, but it may have to create one on the fly, which is inefficient.
8f5ad91b 573L<[perl #116735]|https://rt.perl.org/Ticket/Display.html?id=116735>
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574
575=item *
576
577C<CvGV> (which is not part of the API) is now a more complex macro, which
578may call a function and reify a GV. For those cases where is has been used
579as a boolean, C<CvHASGV> has been added, which will return true for CVs
580that notionally have GVs, but without reifying the GV. C<CvGV> also
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581returns a GV now for lexical subs.
582L<[perl #120441]|https://rt.perl.org/Ticket/Display.html?id=120441>
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584=item *
585
586Added L<perlapi/sync_locale>.
587Changing the program's locale should be avoided by XS code. Nevertheless,
588certain non-Perl libraries called from XS, such as C<Gtk> do so. When this
589happens, Perl needs to be told that the locale has changed. Use this function
590to do so, before returning to Perl.
591
6d9b7c7c 592=back
c1284011 593
6d9b7c7c 594=head1 Selected Bug Fixes
375f5f06 595
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596XXX Important bug fixes in the core language are summarized here. Bug fixes in
597files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
598
599[ List each fix as a =item entry ]
600
0346c3a9 601=over 4
375f5f06 602
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603=item *
604
39c4a6cf 605XXX
2884baee 606
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607=item *
608
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609Constant dereferencing now works correctly for typeglob constants.
610Previously the glob was stringified and its name looked up. Now the glob
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611itself is used.
612L<[perl #69456]|https://rt.perl.org/Ticket/Display.html?id=69456>
6f1a844b 613
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614=item *
615
616When parsing a funny character ($ @ % &) followed by braces, the parser no
617longer tries to guess whether it is a block or a hash constructor (causing
618a syntax error when it guesses the latter), since it can only be a block.
619
be0006e0
FC
620=item *
621
622C<undef $reference> now frees the referent immediately, instead of hanging
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623on to it until the next statement.
624L<[perl #122556]|https://rt.perl.org/Ticket/Display.html?id=122556>
be0006e0 625
1699f5c2
FC
626=item *
627
628Various cases where the name of a sub is used (autoload, overloading, error
629messages) used to crash for lexical subs, but have been fixed.
630
7e8b2071
FC
631=item *
632
633Bareword lookup now tries to avoid vivifying packages if it turns out the
634bareword is not going to be a subroutine name.
635
f9acf899
FC
636=item *
637
638Compilation of anonymous constants (e.g., C<sub () { 3 }>) no longer
639deletes any subroutine named C<__ANON__> in the current package. Not only
640was C<*__ANON__{CODE}> cleared, but there was a memory leak, too. This bug
0d5b620e 641goes back to perl 5.8.0.
f9acf899 642
fd26b6f0
FC
643=item *
644
645Stub declarations like C<sub f;> and C<sub f ();> no longer wipe out
646constants of the same name declared by C<use constant>. This bug was
647introduced in perl 5.10.0.
648
499333dc
KW
649=item *
650
651Under some conditions a warning raised in compilation of regular
652expression patterns could be displayed multiple times. This is now
653fixed.
654
8f0cd35a
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655=item *
656
657C<qr/[\N{named sequence}]/> now works properly in many instances. Some
658names known to C<\N{...}> refer to a sequence of multiple characters,
659instead of the usual single character. Bracketed character classes
660generally only match single characters, but now special handling has
661been added so that they can match named sequences, but not if the class
662is inverted or the sequence is specified as the beginning or end of a
663range. In these cases, the only behavior change from before is a slight
664rewording of the fatal error message given when this class is part of a
665C<?[...])> construct. When the C<[...]> stands alone, the same
666non-fatal warning as before is raised, and only the first character in
667the sequence is used, again just as before.
668
aa292ef2
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669=item *
670
671Tainted constants evaluated at compile time no longer cause unrelated
8f5ad91b
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672statements to become tainted.
673L<[perl #122669]|https://rt.perl.org/Ticket/Display.html?id=122669>
aa292ef2 674
739e9bee
FC
675=item *
676
677C<open $$fh, ...>, which vivifies a handle with a name like "main::_GEN_0",
678was not giving the handle the right reference count, so a double free could
679happen.
680
b23b2fdb
FC
681=item *
682
683When deciding that a bareword was a method name, the parser would get
684confused if an "our" sub with the same name existed, and look up the method
685in the package of the "our" sub, instead of the package of the invocant.
686
7d15b1a8
FC
687=item *
688
689The parser no longer gets confused by C<\U=> within a double-quoted string.
0d5b620e 690It used to produce a syntax error, but now compiles it correctly.
8f5ad91b 691L<[perl #80368]|https://rt.perl.org/Ticket/Display.html?id=80368>
7d15b1a8 692
bbca64cf
KW
693=item *
694
695It has always been the intention for the C<-B> and C<-T> file test
696operators to treat UTF-8 encoded files as text.
697(L<perlfunc|perlfunc/-X FILEHANDLE> has been updated to say this.)
698Previously, it was possible for some files to be considered UTF-8 that
699actually weren't valid UTF-8. This is now fixed. The operators now
700work on EBCDIC platforms as well.
701
0064f8cc
KW
702=item *
703
704Under some conditions warning messages raised during regular expression
705pattern compilation were being output more than once. This has now been
706fixed.
707
6ff8f256
KW
708=item *
709
710A regression has been fixed that was introduced in v5.20.0 (fixed in
711v5.20.1 as well as here) in which a UTF-8 encoded regular expression
712pattern that contains a single ASCII lowercase letter does not match its
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713uppercase counterpart.
714L<[perl #122655]|https://rt.perl.org/Ticket/Display.html?id=122655>
6ff8f256 715
80cc3290
FC
716=item *
717
718Constant folding could incorrectly suppress warnings if lexical warnings
719(C<use warnings> or C<no warnings>) were not in effect and C<$^W> were
720false at compile time and true at run time.
721
13dd5671
FC
722=item *
723
724Loading UTF8 tables during a regular expression match could cause assertion
725failures under debugging builds if the previous match used the very same
8f5ad91b
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726regular expression.
727L<[perl #122747]|https://rt.perl.org/Ticket/Display.html?id=122747>
13dd5671 728
bdab7676
FC
729=item *
730
731Thread cloning used to work incorrectly for lexical subs, possibly causing
732crashes or double frees on exit.
733
3a085d00
FC
734=item *
735
736Since perl 5.14.0, deleting C<$SomePackage::{__ANON__}> and then undefining
737an anonymous subroutine could corrupt things internally, resulting in
738L<Devel::Peek> crashing or L<B.pm|B> giving nonsensical data. This has
739been fixed.
740
caa66803
FC
741=item *
742
743C<(caller $n)[3]> now reports names of lexical subs, instead of treating
744them as "(unknown)".
745
91766151
FC
746=item *
747
748C<sort subname LIST> now supports lexical subs for the comparison routine.
749
dd593f1d
FC
750=item *
751
752Aliasing (e.g., via C<*x = *y>) could confuse list assignments that mention
753the two names for the same variable on either side, causing wrong values to
4c9184fd
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754be assigned.
755L<[perl #15667]|https://rt.perl.org/Ticket/Display.html?id=15667>
dd593f1d 756
fb3b7425
FC
757=item *
758
759Long here-doc terminators could cause a bad read on short lines of input.
760This has been fixed. It is doubtful that any crash could have occurred.
761This bug goes back to when here-docs were introduced in perl 3.000
762twenty-five years ago.
763
39c4a6cf 764=back
b756670b 765
39c4a6cf 766=head1 Known Problems
b756670b 767
39c4a6cf
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768XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
769tests that had to be C<TODO>ed for the release would be noted here. Unfixed
770platform specific bugs also go here.
e917e94e 771
39c4a6cf
PM
772[ List each fix as a =item entry ]
773
774=over 4
e917e94e 775
26dd5fd6
PM
776=item *
777
39c4a6cf 778XXX
26dd5fd6 779
13900f93
A
780=back
781
39c4a6cf 782=head1 Errata From Previous Releases
e831f11a 783
39c4a6cf
PM
784=over 4
785
786=item *
ff433f2d 787
39c4a6cf
PM
788XXX Add anything here that we forgot to add, or were mistaken about, in
789the perldelta of a previous release.
ff433f2d 790
39c4a6cf
PM
791=back
792
793=head1 Obituary
ff433f2d 794
39c4a6cf
PM
795XXX If any significant core contributor has died, we've added a short obituary
796here.
ff433f2d 797
39c4a6cf 798=head1 Acknowledgements
ff433f2d 799
39c4a6cf 800XXX Generate this with:
e831f11a 801
39c4a6cf 802 perl Porting/acknowledgements.pl v5.21.3..HEAD
f5b73711 803
44691e6f
AB
804=head1 Reporting Bugs
805
e08634c5
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806If you find what you think is a bug, you might check the articles recently
807posted to the comp.lang.perl.misc newsgroup and the perl bug database at
238894db 808https://rt.perl.org/ . There may also be information at
7ef8b31d 809http://www.perl.org/ , the Perl Home Page.
44691e6f 810
e08634c5
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811If you believe you have an unreported bug, please run the L<perlbug> program
812included with your release. Be sure to trim your bug down to a tiny but
813sufficient test case. Your bug report, along with the output of C<perl -V>,
814will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
44691e6f
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815
816If the bug you are reporting has security implications, which make it
e08634c5
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817inappropriate to send to a publicly archived mailing list, then please send it
818to perl5-security-report@perl.org. This points to a closed subscription
819unarchived mailing list, which includes all the core committers, who will be
820able to help assess the impact of issues, figure out a resolution, and help
f9001595 821co-ordinate the release of patches to mitigate or fix the problem across all
e08634c5
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822platforms on which Perl is supported. Please only use this address for
823security issues in the Perl core, not for modules independently distributed on
824CPAN.
44691e6f
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825
826=head1 SEE ALSO
827
e08634c5
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828The F<Changes> file for an explanation of how to view exhaustive details on
829what changed.
44691e6f
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830
831The F<INSTALL> file for how to build Perl.
832
833The F<README> file for general stuff.
834
835The F<Artistic> and F<Copying> files for copyright information.
836
837=cut