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perldelta for #3105/5608dcc
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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 v5.19.3
e128ab2c 9
4eabcf70 10=head1 DESCRIPTION
6db9054f 11
12dcbffb 12This document describes differences between the 5.19.2 release and the 5.19.3
e08634c5 13release.
6db9054f 14
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15If you are upgrading from an earlier release such as 5.19.1, first read
16L<perl5192delta>, which describes differences between 5.19.1 and 5.19.2.
42bff0d9 17
12dcbffb 18=head1 Notice
42bff0d9 19
12dcbffb 20XXX Any important notices here
42bff0d9 21
12dcbffb 22=head1 Core Enhancements
c0ca71c9 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.
c0ca71c9 27
12dcbffb 28[ List each enhancement as a =head2 entry ]
c0ca71c9 29
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30=head2 B<-F> now implies B<-a> and B<-a> implies B<-n>
31
32Previously B<-F> without B<-a> was a no-op, and B<-a> without B<-n> or
33B<-p> was a no-op, with this change, if you supply B<-F> then both
34B<-a> and B<-n> are implied and if you supply B<-a> then B<-n> is implied.
35
36You can still use B<-p> for its extra behaviour. [perl #116190]
37
12dcbffb 38=head1 Security
c0ca71c9 39
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40XXX Any security-related notices go here. In particular, any security
41vulnerabilities closed should be noted here rather than in the
42L</Selected Bug Fixes> section.
c0ca71c9 43
12dcbffb 44[ List each security issue as a =head2 entry ]
c0ca71c9 45
12dcbffb 46=head1 Incompatible Changes
c0ca71c9 47
12dcbffb 48XXX For a release on a stable branch, this section aspires to be:
c0ca71c9 49
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50 There are no changes intentionally incompatible with 5.XXX.XXX
51 If any exist, they are bugs, and we request that you submit a
52 report. See L</Reporting Bugs> below.
c0ca71c9 53
12dcbffb 54[ List each incompatible change as a =head2 entry ]
c0ca71c9 55
12dcbffb 56=head1 Deprecations
c0ca71c9 57
12dcbffb 58XXX Any deprecated features, syntax, modules etc. should be listed here.
c0ca71c9 59
12dcbffb 60=head2 Module removals
c0ca71c9 61
12dcbffb 62XXX Remove this section if inapplicable.
c0ca71c9 63
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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.
c0ca71c9 68
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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.
c0ca71c9 72
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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.
c0ca71c9 77
12dcbffb 78=over
c0ca71c9 79
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80XXX Note that deprecated modules should be listed here even if they are listed
81as an updated module in the L</Modules and Pragmata> section.
c0ca71c9 82
12dcbffb 83=back
c0ca71c9 84
12dcbffb 85[ List each other deprecation as a =head2 entry ]
c0ca71c9 86
12dcbffb 87=head1 Performance Enhancements
c0ca71c9 88
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89XXX Changes which enhance performance without changing behaviour go here.
90There may well be none in a stable release.
c0ca71c9 91
12dcbffb 92[ List each enhancement as a =item entry ]
c0ca71c9 93
12dcbffb 94=over 4
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95
96=item *
97
12dcbffb 98XXX
c0ca71c9 99
12dcbffb 100=back
70ba8092 101
12dcbffb 102=head1 Modules and Pragmata
42bff0d9 103
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104XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
105go here. If Module::CoreList is updated, generate an initial draft of the
106following sections using F<Porting/corelist-perldelta.pl>, which prints stub
107entries to STDOUT. Results can be pasted in place of the '=head2' entries
108below. A paragraph summary for important changes should then be added by hand.
109In an ideal world, dual-life modules would have a F<Changes> file that could be
110cribbed.
6e4979f3 111
12dcbffb 112[ Within each section, list entries as a =item entry ]
6e4979f3 113
12dcbffb 114=head2 New Modules and Pragmata
6e4979f3 115
12dcbffb 116=over 4
42bff0d9 117
c0ca71c9 118=item *
42bff0d9 119
12dcbffb 120XXX
42bff0d9 121
12dcbffb 122=back
42bff0d9 123
12dcbffb 124=head2 Updated Modules and Pragmata
42bff0d9 125
12dcbffb 126=over 4
42bff0d9 127
c0ca71c9 128=item *
42bff0d9 129
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130L<B> has been upgraded from version 1.44 to 1.45.
131
132Calling the C<GV> method on C<B::CV> objects created from a lexical
133sub would return nonsense, possibly crashing perl. C<GV> now returns
134C<undef> for lexical subs. [perl #118525]
135
136Added the C<NAME_HEK> method to return the name of a lexical sub.
137
138=item *
139
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140L<bignum> has been upgraded from version 0.35 to 0.36.
141
142L<bigrat> wasn't correctly updating an internal variable when C<use>d
143with a C<lib> option.
144
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145L<Carp> has been upgraded from 1.30 to 1.31
146
147L<Carp> now handles objects with string overloads. It also allows objects
148to specify how they appear in the stack dump with a C<CARP_TRACE> method,
149and also allows the user to specify their own formatter for objects without
150C<CARP_TRACE> as well as other references. [perl #92446]
151
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152=item *
153
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154L<Compress::Raw::Bzip2> has been upgraded from 2.061 to 2.062.
155
156=item *
157
158L<Compress::Raw::Zlib> has been upgraded from 2.061 to 2.062.
159
160=item *
161
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162L<Config::Perl::V> has been upgraded from version 0.18 to 0.19.
163
164=item *
165
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166L<Data::Dumper> has been upgraded from version 2.147 to 2.148.
167
168The compatbility of the XS implementation with the pure perl version
169under C<Useqq> has been improved. [perl #118933]
42bff0d9 170
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171=item *
172
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173L<Devel::Peek> has been upgraded from version 1.12 to 1.13.
174
175The C<SvREFCNT_inc()> and C<SvREFCNT_dec()> functions have been
176removed and C<SvREFCNT()> will now work on non-scalars. [perl #117793]
177
178=item *
179
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180L<Exporter> has been upgraded from version 5.68 to 5.69.
181
182L<Exporter> would ignore custom C<$SIG{__WARN__}> handlers in
183C<Exporter::Heavy>. [perl #39739]
184
185=item *
186
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187The IO-Compress module collection has been upgraded from 2.061 to 2.062.
188
189=item *
190
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191L<IPC::Cmd> has been upgraded from version 0.82 to 0.84.
192
193C<run_forked> has various fixes/improvements, L<Socket> is only used where
194needed and a regression introduced in 0.78 has been fixed.
195
196=item *
197
07513bb4 198The libnet module collection has been upgraded from version 1.22 to 1.23.
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199
200=item *
201
6a9ebaf3 202L<List::Util> has been upgraded from version 1.27 to 1.30
2dc8d725 203
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204L<List::Util> now includes C<pairgrep>, C<pairmap>, C<pairs>, C<pairkeys>,
205C<pairvalues> and C<pairfirst> functions that operate on even-sized lists of
206pairs.
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207
208=item *
209
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210L<parent> has been upgraded from version 0.225 to 0.226.
211
212=item *
213
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214L<Socket> has been upgraded from version 2.010 to 2.011.
215
216Handle FreeBSD (or other platforms) returning shorter AF_UNIX sockaddr
217structures due to embedded sun_len. [cpan #86613]
218
219=item *
220
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221L<Storable> has been upgraded from version 2.45 to 2.46.
222
223Avoid creating temporary objects for STORABLE_attach when they aren't
224required. [perl #118907]
225
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226=item *
227
228L<Time::Piece> has been upgraded from version 1.21 to 1.22.
229
c0ca71c9 230=back
42bff0d9 231
12dcbffb 232=head2 Removed Modules and Pragmata
dbd04185 233
38663f11 234=over 4
583aa5c2 235
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236=item *
237
12dcbffb 238XXX
42bff0d9 239
38663f11 240=back
42bff0d9 241
12dcbffb 242=head1 Documentation
989e4501 243
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244XXX Changes to files in F<pod/> go here. Consider grouping entries by
245file and be sure to link to the appropriate page, e.g. L<perlfunc>.
989e4501 246
12dcbffb 247=head2 New Documentation
989e4501 248
12dcbffb 249XXX Changes which create B<new> files in F<pod/> go here.
42bff0d9 250
12dcbffb 251=head3 L<XXX>
42bff0d9 252
12dcbffb 253XXX Description of the purpose of the new file here
42bff0d9 254
12dcbffb 255=head2 Changes to Existing Documentation
42bff0d9 256
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257XXX Changes which significantly change existing files in F<pod/> go here.
258However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
259section.
42bff0d9 260
3031ec7a 261=head3 L<perlopentut>
42bff0d9 262
38663f11 263=over 4
42bff0d9
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264
265=item *
266
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267The C<open> tutorial has been completely rewriten by Tom Christiansen, and now
268focuses on covering only the basics, rather than providing a comprehensive
269reference to all things openable. This rewrite came as the result of a
270vigorous discussion on perl5-porters kicked off by a set of improvements
271written by Alexander Hartmaier to the existing C<perlopentut>. A "more than
272you ever wanted to know about C<open>" document may follow in subsequent
273versions of perl.
1fdd5e53 274
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275=back
276
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277=head1 Diagnostics
278
279The following additions or changes have been made to diagnostic output,
280including warnings and fatal error messages. For the complete list of
281diagnostic messages, see L<perldiag>.
282
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283XXX New or changed warnings emitted by the core's C<C> code go here. Also
284include any changes in L<perldiag> that reconcile it to the C<C> code.
285
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286=head2 New Diagnostics
287
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288XXX Newly added diagnostic messages go under here, separated into New Errors
289and New Warnings
290
291=head3 New Errors
583aa5c2 292
38663f11 293=over 4
583aa5c2 294
b8a02ff1 295=item *
583aa5c2 296
12dcbffb 297XXX L<message|perldiag/"message">
583aa5c2 298
b8a02ff1 299=back
583aa5c2 300
12dcbffb 301=head3 New Warnings
96d496e4 302
38663f11 303=over 4
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304
305=item *
306
12dcbffb 307XXX L<message|perldiag/"message">
96d496e4 308
12dcbffb 309=back
1310e590 310
12dcbffb 311=head2 Changes to Existing Diagnostics
e727f86a 312
12dcbffb 313XXX Changes (i.e. rewording) of diagnostic messages go here
e727f86a 314
12dcbffb 315=over 4
e727f86a 316
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317=item *
318
12dcbffb 319XXX Describe change here
81ca6d44 320
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321=back
322
12dcbffb 323=head1 Utility Changes
583aa5c2 324
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325XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go here.
326Most of these are built within the directories F<utils> and F<x2p>.
71e6aba6 327
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328[ List utility changes as a =head3 entry for each utility and =item
329entries for each change
330Use L<XXX> with program names to get proper documentation linking. ]
d5f315e8 331
12dcbffb 332=head3 L<XXX>
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333
334=over 4
335
336=item *
337
12dcbffb 338XXX
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339
340=back
341
12dcbffb 342=head1 Configuration and Compilation
2426c394 343
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344XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
345go here. Any other changes to the Perl build process should be listed here.
346However, any platform-specific changes should be listed in the
347L</Platform Support> section, instead.
4724da03 348
12dcbffb 349[ List changes as a =item entry ].
583aa5c2 350
38663f11 351=over 4
a34da6c4 352
12dcbffb 353=item *
a34da6c4 354
12dcbffb 355XXX
a34da6c4 356
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357=back
358
12dcbffb 359=head1 Testing
583aa5c2 360
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361XXX Any significant changes to the testing of a freshly built perl should be
362listed here. Changes which create B<new> files in F<t/> go here as do any
363large changes to the testing harness (e.g. when parallel testing was added).
364Changes to existing files in F<t/> aren't worth summarizing, although the bugs
365that they represent may be covered elsewhere.
1de7c8e6 366
12dcbffb 367[ List each test improvement as a =item entry ]
9c800862 368
12dcbffb 369=over 4
aaf54772 370
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371=item *
372
12dcbffb 373XXX
b7bbd8b6 374
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375=back
376
12dcbffb 377=head1 Platform Support
d7bfa554 378
12dcbffb 379XXX Any changes to platform support should be listed in the sections below.
81d3ed5a 380
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381[ Within the sections, list each platform as a =item entry with specific
382changes as paragraphs below it. ]
81d3ed5a 383
12dcbffb 384=head2 New Platforms
0b023496 385
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386XXX List any platforms that this version of perl compiles on, that previous
387versions did not. These will either be enabled by new files in the F<hints/>
388directories, or new subdirectories and F<README> files at the top level of the
389source tree.
0b023496 390
12dcbffb 391=over 4
e11f653d 392
12dcbffb 393=item XXX-some-platform
5e0164b2 394
12dcbffb 395XXX
5e0164b2 396
12dcbffb 397=back
e11f653d 398
12dcbffb 399=head2 Discontinued Platforms
8be8cdec 400
12dcbffb 401XXX List any platforms that this version of perl no longer compiles on.
8be8cdec 402
12dcbffb 403=over 4
07a522a5 404
12dcbffb 405=item XXX-some-platform
07a522a5 406
12dcbffb 407XXX
71b4007c 408
12dcbffb 409=back
71b4007c 410
12dcbffb 411=head2 Platform-Specific Notes
f6b1d2f5 412
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413XXX List any changes for specific platforms. This could include configuration
414and compilation changes or changes in portability/compatibility. However,
415changes within modules for platforms should generally be listed in the
416L</Modules and Pragmata> section.
f6b1d2f5 417
12dcbffb 418=over 4
7e4f209b 419
12dcbffb 420=item XXX-some-platform
7e4f209b 421
12dcbffb 422XXX
558673e6 423
12dcbffb 424=back
558673e6 425
12dcbffb 426=head1 Internal Changes
47a7c93d 427
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428XXX Changes which affect the interface available to C<XS> code go here. Other
429significant internal changes for future core maintainers should be noted as
430well.
47a7c93d 431
12dcbffb 432[ List each change as a =item entry ]
b5a80c26 433
12dcbffb 434=over 4
b5a80c26 435
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436=item *
437
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438C<sv_pos_b2u_flags> has been added to the API. It is similar to
439C<sv_pos_b2u>, but supports long strings on 64-bit platforms.
7f1d4316 440
12dcbffb 441=back
02bef66e 442
12dcbffb 443=head1 Selected Bug Fixes
d30fb844 444
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445XXX Important bug fixes in the core language are summarized here. Bug fixes in
446files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
d30fb844 447
12dcbffb 448[ List each fix as a =item entry ]
21c01741 449
12dcbffb 450=over 4
21c01741 451
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452=item *
453
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454Autovivifying a subroutine stub via C<\&$glob> started causing crashes in
455Perl 5.18.0 if the $glob was merely a copy of a real glob, i.e., a scalar
456that had had a glob assigned to it. This has been fixed [perl #119051].
467582e8 457
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458=item *
459
460On 64-bit platforms C<pos> can now be set to a value higher than 2**31-1
461[perl #72766].
462
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463=item *
464
465Perl used to leak an implementation detail when it came to referencing the
466return values of certain operators. C<for ($a+$b) { warn \$_; warn \$_ }>
467used to display two different memory addresses, because the C<\> operator
468was copying the variable. Under threaded builds, it would also happen for
469constants (C<for(1) { ... }>). This has been fixed [perl #21979, #78194,
470#89188, #109746, #114838, #115388].
471
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472=item *
473
474The range operator C<..> was returning the same modifiable scalars with
475each call, unless it was the only thing in a C<foreach> loop header. This
476meant that changes to values within the list returned would be visible the
477next time the operator was executed [perl #3105].
478
38663f11 479=back
d7bfa554 480
38663f11 481=head1 Known Problems
6810f0ad 482
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483XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
484tests that had to be C<TODO>ed for the release would be noted here. Unfixed
485platform specific bugs also go here.
486
487[ List each fix as a =item entry ]
488
38663f11 489=over 4
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490
491=item *
492
12dcbffb 493XXX
0e417e4d 494
38663f11 495=back
583aa5c2 496
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497=head1 Obituary
498
499XXX If any significant core contributor has died, we've added a short obituary
500here.
501
583aa5c2 502=head1 Acknowledgements
a75569c0 503
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504XXX Generate this with:
505
506 perl Porting/acknowledgements.pl v5.19.2..HEAD
f5b73711 507
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508=head1 Reporting Bugs
509
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510If you find what you think is a bug, you might check the articles recently
511posted to the comp.lang.perl.misc newsgroup and the perl bug database at
512http://rt.perl.org/perlbug/ . There may also be information at
513http://www.perl.org/ , the Perl Home Page.
44691e6f 514
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515If you believe you have an unreported bug, please run the L<perlbug> program
516included with your release. Be sure to trim your bug down to a tiny but
517sufficient test case. Your bug report, along with the output of C<perl -V>,
518will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
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519
520If the bug you are reporting has security implications, which make it
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521inappropriate to send to a publicly archived mailing list, then please send it
522to perl5-security-report@perl.org. This points to a closed subscription
523unarchived mailing list, which includes all the core committers, who will be
524able to help assess the impact of issues, figure out a resolution, and help
f9001595 525co-ordinate the release of patches to mitigate or fix the problem across all
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526platforms on which Perl is supported. Please only use this address for
527security issues in the Perl core, not for modules independently distributed on
528CPAN.
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529
530=head1 SEE ALSO
531
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532The F<Changes> file for an explanation of how to view exhaustive details on
533what changed.
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534
535The F<INSTALL> file for how to build Perl.
536
537The F<README> file for general stuff.
538
539The F<Artistic> and F<Copying> files for copyright information.
540
541=cut