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Upgrade ExtUtils::CBuilder from version 0.280217 to 0.280219
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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
0346c3a9 30=head1 Security
7e957246 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.
13900f93 35
39c4a6cf 36[ List each security issue as a =head2 entry ]
8bdb3f93 37
13900f93 38=head1 Incompatible Changes
8bdb3f93 39
39c4a6cf 40XXX For a release on a stable branch, this section aspires to be:
1178d2cf 41
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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.
1178d2cf 45
39c4a6cf 46[ List each incompatible change as a =head2 entry ]
f6f3144e 47
39c4a6cf 48=head1 Deprecations
7065301c 49
39c4a6cf 50XXX Any deprecated features, syntax, modules etc. should be listed here.
7065301c 51
39c4a6cf 52=head2 Module removals
b3e82ed1 53
39c4a6cf 54XXX Remove this section if inapplicable.
ca58223b 55
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56The following modules will be removed from the core distribution in a
57future release, and will at that time need to be installed from CPAN.
58Distributions on CPAN which require these modules will need to list them as
59prerequisites.
ca58223b 60
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61The core versions of these modules will now issue C<"deprecated">-category
62warnings to alert you to this fact. To silence these deprecation warnings,
63install the modules in question from CPAN.
23b03637 64
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65Note that these are (with rare exceptions) fine modules that you are encouraged
66to continue to use. Their disinclusion from core primarily hinges on their
67necessity to bootstrapping a fully functional, CPAN-capable Perl installation,
68not usually on concerns over their design.
23b03637 69
39c4a6cf 70=over
85e8fb10 71
39c4a6cf 72=item XXX
85e8fb10 73
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74XXX Note that deprecated modules should be listed here even if they are listed
75as an updated module in the L</Modules and Pragmata> section.
134f90c2 76
39c4a6cf 77=back
134f90c2 78
39c4a6cf 79[ List each other deprecation as a =head2 entry ]
ff433f2d 80
39c4a6cf 81=head1 Performance Enhancements
ff433f2d 82
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83XXX Changes which enhance performance without changing behaviour go here.
84There may well be none in a stable release.
134f90c2 85
39c4a6cf 86[ List each enhancement as a =item entry ]
134f90c2 87
39c4a6cf 88=over 4
7d19f6a1 89
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90=item *
91
39c4a6cf 92XXX
55e8b286 93
39c4a6cf 94=back
55e8b286 95
39c4a6cf 96=head1 Modules and Pragmata
d99849ae 97
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98XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
99go here. If Module::CoreList is updated, generate an initial draft of the
100following sections using F<Porting/corelist-perldelta.pl>. A paragraph summary
101for important changes should then be added by hand. In an ideal world,
102dual-life modules would have a F<Changes> file that could be cribbed.
d99849ae 103
39c4a6cf 104[ Within each section, list entries as a =item entry ]
ff433f2d 105
39c4a6cf 106=head2 New Modules and Pragmata
ff433f2d 107
39c4a6cf 108=over 4
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109
110=item *
111
39c4a6cf 112XXX
0bb39c26 113
39c4a6cf 114=back
0bb39c26 115
39c4a6cf 116=head2 Updated Modules and Pragmata
9c97a342 117
39c4a6cf 118=over 4
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119
120=item *
121
39c4a6cf 122L<XXX> has been upgraded from version A.xx to B.yy.
6ab3666b 123
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124=item *
125
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126L<B::Concise> has been upgraded from version 0.992 to 0.993.
127
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128=item *
129
130L<CPAN::Meta::Requirements> has been upgraded from version 2.126 to 2.128.
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131
132=item *
133
134L<ExtUtils::CBuilder> has been upgraded from version 0.280216 to 0.280219.
135[perl #122675].
136
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137=item *
138
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139L<ExtUtils::Manifest> has been upgraded from version 1.65 to 1.66.
140[perl #122415].
141
142=item *
143
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144L<File::Find> has been upgraded from version 1.27 to 1.28.
145
146C<find()> and C<finddepth()> will now warn if passed inappropriate or
147misspelled options.
148
149=item *
150
151L<Getopt::Std> has been upgraded from version 1.10 to 1.11.
152
153=item *
154
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155L<HTTP::Tiny> has been upgraded from version 0.047 to 0.048.
156
157=item *
158
159L<Module::CoreList> has been upgraded from version 5.021003 to 5.021004.
160
161=item *
162
163L<POSIX> has been upgraded from version 1.42 to 1.43.
164
165=item *
166
167L<Pod::Perldoc> has been upgraded from version 3.23 to 3.24.
168
169=item *
170
171L<constant> has been upgraded from version 1.31 to 1.32.
172
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173It now accepts fully-qualified constant names, allowing constants to be
174defined in packages other than the caller.
175
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176=item *
177
178L<threads> has been upgraded from version 1.95 to 1.96.
179
39c4a6cf 180=back
9c97a342 181
39c4a6cf 182=head2 Removed Modules and Pragmata
d99849ae 183
39c4a6cf 184=over 4
d99849ae 185
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186=item *
187
39c4a6cf 188XXX
ff433f2d 189
13900f93 190=back
aac7f82f 191
13900f93 192=head1 Documentation
aac7f82f 193
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194XXX Changes to files in F<pod/> go here. Consider grouping entries by
195file and be sure to link to the appropriate page, e.g. L<perlfunc>.
6d9b7c7c 196
39c4a6cf 197=head2 New Documentation
2a395b86 198
39c4a6cf 199XXX Changes which create B<new> files in F<pod/> go here.
2a395b86 200
39c4a6cf 201=head3 L<XXX>
2a395b86 202
39c4a6cf 203XXX Description of the purpose of the new file here
2a395b86 204
39c4a6cf 205=head2 Changes to Existing Documentation
2a395b86 206
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207XXX Changes which significantly change existing files in F<pod/> go here.
208However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
209section.
210
211=head3 L<XXX>
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212
213=over 4
214
215=item *
216
39c4a6cf 217XXX Description of the change here
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218
219=back
220
39c4a6cf 221=head1 Diagnostics
2a395b86 222
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223The following additions or changes have been made to diagnostic output,
224including warnings and fatal error messages. For the complete list of
225diagnostic messages, see L<perldiag>.
2a395b86 226
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227XXX New or changed warnings emitted by the core's C<C> code go here. Also
228include any changes in L<perldiag> that reconcile it to the C<C> code.
2a395b86 229
39c4a6cf 230=head2 New Diagnostics
0f4a583b 231
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232XXX Newly added diagnostic messages go under here, separated into New Errors
233and New Warnings
2a395b86 234
39c4a6cf 235=head3 New Errors
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236
237=over 4
238
239=item *
240
39c4a6cf 241XXX L<message|perldiag/"message">
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242
243=back
244
39c4a6cf 245=head3 New Warnings
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246
247=over 4
248
249=item *
250
39c4a6cf 251XXX L<message|perldiag/"message">
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252
253=back
6d9b7c7c 254
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255=head2 Changes to Existing Diagnostics
256
257XXX Changes (i.e. rewording) of diagnostic messages go here
7f55cec0 258
13900f93 259=over 4
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260
261=item *
262
39c4a6cf 263XXX Describe change here
aac7f82f 264
13900f93 265=back
aac7f82f 266
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267=head2 Diagnostic Removals
268
269=over 4
270
271=item *
272
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273"Constant is not a FOO reference"
274
275Compile-time checking of constant dereferencing (e.g.,
276C<< my_constant->() >>) has been removed, since it was not taking
277overloading into account. [perl #69456] [perl #122607]
278
279=item *
280
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281The warning "Ambiguous use of -foo resolved as -&foo()" has been removed.
282There is actually no ambiguity here, and this impedes the use of negated
283constants; e.g., C<-Inf>.
284
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285=item *
286
287The little-known C<my Class $var> syntax (see L<fields> and L<attributes>)
288could get confused in the scope of C<use utf8> if C<Class> were a constant
289whose value contained Latin-1 characters.
290
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291=back
292
39c4a6cf 293=head1 Utility Changes
091fed7c 294
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295XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go here.
296Most of these are built within the directory F<utils>.
902c1f75 297
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298[ List utility changes as a =head2 entry for each utility and =item
299entries for each change
300Use L<XXX> with program names to get proper documentation linking. ]
2901561d 301
39c4a6cf 302=head2 L<XXX>
4594cf53 303
13900f93 304=over 4
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305
306=item *
307
39c4a6cf 308XXX
a1d26ccd 309
39c4a6cf 310=back
a1d26ccd 311
39c4a6cf 312=head1 Configuration and Compilation
7065301c 313
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314XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
315go here. Any other changes to the Perl build process should be listed here.
316However, any platform-specific changes should be listed in the
317L</Platform Support> section, instead.
58f25ac1 318
39c4a6cf 319[ List changes as a =item entry ].
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320
321=over 4
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322
323=item *
324
39c4a6cf 325XXX
a5873648 326
39c4a6cf 327=back
a5873648 328
39c4a6cf 329=head1 Testing
a5873648 330
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331XXX Any significant changes to the testing of a freshly built perl should be
332listed here. Changes which create B<new> files in F<t/> go here as do any
333large changes to the testing harness (e.g. when parallel testing was added).
334Changes to existing files in F<t/> aren't worth summarizing, although the bugs
335that they represent may be covered elsewhere.
a5873648 336
39c4a6cf 337[ List each test improvement as a =item entry ]
a5873648 338
39c4a6cf 339=over 4
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340
341=item *
342
39c4a6cf 343XXX
a5873648 344
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345=back
346
39c4a6cf 347=head1 Platform Support
b10906fb 348
39c4a6cf 349XXX Any changes to platform support should be listed in the sections below.
b10906fb 350
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351[ Within the sections, list each platform as a =item entry with specific
352changes as paragraphs below it. ]
b10906fb 353
39c4a6cf 354=head2 New Platforms
b10906fb 355
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356XXX List any platforms that this version of perl compiles on, that previous
357versions did not. These will either be enabled by new files in the F<hints/>
358directories, or new subdirectories and F<README> files at the top level of the
359source tree.
13900f93 360
7065301c 361=over 4
24a38d90 362
39c4a6cf 363=item XXX-some-platform
24a38d90 364
39c4a6cf 365XXX
bb076206 366
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367=back
368
39c4a6cf 369=head2 Discontinued Platforms
097675bf 370
39c4a6cf 371XXX List any platforms that this version of perl no longer compiles on.
b3211734 372
6e97d65d 373=over 4
b3211734 374
39c4a6cf 375=item XXX-some-platform
7065301c 376
39c4a6cf 377XXX
13900f93 378
39c4a6cf 379=back
7d0ccdba 380
39c4a6cf 381=head2 Platform-Specific Notes
7d0ccdba 382
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383XXX List any changes for specific platforms. This could include configuration
384and compilation changes or changes in portability/compatibility. However,
385changes within modules for platforms should generally be listed in the
386L</Modules and Pragmata> section.
6e97d65d 387
39c4a6cf 388=over 4
6e97d65d 389
39c4a6cf 390=item XXX-some-platform
6e97d65d 391
39c4a6cf 392XXX
7d0ccdba 393
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394=back
395
396=head1 Internal Changes
397
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398XXX Changes which affect the interface available to C<XS> code go here. Other
399significant internal changes for future core maintainers should be noted as
400well.
c9fcb674 401
39c4a6cf 402[ List each change as a =item entry ]
a835cd47 403
39c4a6cf 404=over 4
c1284011 405
7d15b1a8 406XXX
1c43698b 407
6d9b7c7c 408=back
c1284011 409
6d9b7c7c 410=head1 Selected Bug Fixes
375f5f06 411
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412XXX Important bug fixes in the core language are summarized here. Bug fixes in
413files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
414
415[ List each fix as a =item entry ]
416
0346c3a9 417=over 4
375f5f06 418
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419=item *
420
39c4a6cf 421XXX
2884baee 422
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423=item *
424
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425Constant dereferencing now works correctly for typeglob constants.
426Previously the glob was stringified and its name looked up. Now the glob
427itself is used. [perl #69456]
428
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429=item *
430
431When parsing a funny character ($ @ % &) followed by braces, the parser no
432longer tries to guess whether it is a block or a hash constructor (causing
433a syntax error when it guesses the latter), since it can only be a block.
434
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435=item *
436
437C<undef $reference> now frees the referent immediately, instead of hanging
438on to it until the next statement. [perl #122556]
439
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440=item *
441
442Various cases where the name of a sub is used (autoload, overloading, error
443messages) used to crash for lexical subs, but have been fixed.
444
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445=item *
446
447Bareword lookup now tries to avoid vivifying packages if it turns out the
448bareword is not going to be a subroutine name.
449
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450=item *
451
452Compilation of anonymous constants (e.g., C<sub () { 3 }>) no longer
453deletes any subroutine named C<__ANON__> in the current package. Not only
454was C<*__ANON__{CODE}> cleared, but there was a memory leak, too. This bug
455goes back to perl 5.8.0.
456
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457=item *
458
459Stub declarations like C<sub f;> and C<sub f ();> no longer wipe out
460constants of the same name declared by C<use constant>. This bug was
461introduced in perl 5.10.0.
462
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463=item *
464
465Under some conditions a warning raised in compilation of regular
466expression patterns could be displayed multiple times. This is now
467fixed.
468
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469=item *
470
471C<qr/[\N{named sequence}]/> now works properly in many instances. Some
472names known to C<\N{...}> refer to a sequence of multiple characters,
473instead of the usual single character. Bracketed character classes
474generally only match single characters, but now special handling has
475been added so that they can match named sequences, but not if the class
476is inverted or the sequence is specified as the beginning or end of a
477range. In these cases, the only behavior change from before is a slight
478rewording of the fatal error message given when this class is part of a
479C<?[...])> construct. When the C<[...]> stands alone, the same
480non-fatal warning as before is raised, and only the first character in
481the sequence is used, again just as before.
482
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483=item *
484
485Tainted constants evaluated at compile time no longer cause unrelated
486statements to become tainted. [perl #122669]
487
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488=item *
489
490C<open $$fh, ...>, which vivifies a handle with a name like "main::_GEN_0",
491was not giving the handle the right reference count, so a double free could
492happen.
493
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494=item *
495
496When deciding that a bareword was a method name, the parser would get
497confused if an "our" sub with the same name existed, and look up the method
498in the package of the "our" sub, instead of the package of the invocant.
499
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500=item *
501
502The parser no longer gets confused by C<\U=> within a double-quoted string.
503It used to roduce a syntax error, but now compiles it correctly.
504[perl #80368]
505
39c4a6cf 506=back
b756670b 507
39c4a6cf 508=head1 Known Problems
b756670b 509
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510XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
511tests that had to be C<TODO>ed for the release would be noted here. Unfixed
512platform specific bugs also go here.
e917e94e 513
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514[ List each fix as a =item entry ]
515
516=over 4
e917e94e 517
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518=item *
519
39c4a6cf 520XXX
26dd5fd6 521
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522=back
523
39c4a6cf 524=head1 Errata From Previous Releases
e831f11a 525
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526=over 4
527
528=item *
ff433f2d 529
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530XXX Add anything here that we forgot to add, or were mistaken about, in
531the perldelta of a previous release.
ff433f2d 532
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533=back
534
535=head1 Obituary
ff433f2d 536
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537XXX If any significant core contributor has died, we've added a short obituary
538here.
ff433f2d 539
39c4a6cf 540=head1 Acknowledgements
ff433f2d 541
39c4a6cf 542XXX Generate this with:
e831f11a 543
39c4a6cf 544 perl Porting/acknowledgements.pl v5.21.3..HEAD
f5b73711 545
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546=head1 Reporting Bugs
547
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548If you find what you think is a bug, you might check the articles recently
549posted to the comp.lang.perl.misc newsgroup and the perl bug database at
238894db 550https://rt.perl.org/ . There may also be information at
7ef8b31d 551http://www.perl.org/ , the Perl Home Page.
44691e6f 552
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553If you believe you have an unreported bug, please run the L<perlbug> program
554included with your release. Be sure to trim your bug down to a tiny but
555sufficient test case. Your bug report, along with the output of C<perl -V>,
556will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
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557
558If the bug you are reporting has security implications, which make it
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559inappropriate to send to a publicly archived mailing list, then please send it
560to perl5-security-report@perl.org. This points to a closed subscription
561unarchived mailing list, which includes all the core committers, who will be
562able to help assess the impact of issues, figure out a resolution, and help
f9001595 563co-ordinate the release of patches to mitigate or fix the problem across all
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564platforms on which Perl is supported. Please only use this address for
565security issues in the Perl core, not for modules independently distributed on
566CPAN.
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567
568=head1 SEE ALSO
569
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570The F<Changes> file for an explanation of how to view exhaustive details on
571what changed.
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572
573The F<INSTALL> file for how to build Perl.
574
575The F<README> file for general stuff.
576
577The F<Artistic> and F<Copying> files for copyright information.
578
579=cut