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perldelta for 60df683
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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 v5.21.3
c68523cb 9
238894db 10=head1 DESCRIPTION
c68523cb 11
13900f93 12This document describes differences between the 5.21.2 release and the 5.21.3
238894db 13release.
c68523cb 14
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15If you are upgrading from an earlier release such as 5.21.1, first read
16L<perl5212delta>, which describes differences between 5.21.1 and 5.21.2.
17
18=head1 Notice
19
20XXX Any important notices here
7065301c 21
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22=head1 Core Enhancements
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.
7e957246 27
13900f93 28[ List each enhancement as a =head2 entry ]
7e957246 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.
35
36[ List each security issue as a =head2 entry ]
8bdb3f93 37
13900f93 38=head1 Incompatible Changes
8bdb3f93 39
13900f93 40XXX For a release on a stable branch, this section aspires to be:
8bdb3f93 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.
45
46[ List each incompatible change as a =head2 entry ]
cd209d9d 47
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48=head2 S<C<use UNIVERSAL '...'>> is now a fatal error
49
50Importing functions from C<UNIVERSAL> has been deprecated since v5.12, and
51is now a fatal error. S<C<"use UNIVERSAL">> without any arguments is still
52allowed.
53
0346c3a9 54=head1 Deprecations
5320b60d 55
13900f93 56XXX Any deprecated features, syntax, modules etc. should be listed here.
36304e49 57
13900f93 58=head2 Module removals
7065301c 59
13900f93 60XXX Remove this section if inapplicable.
df758df2 61
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62The following modules will be removed from the core distribution in a
63future release, and will at that time need to be installed from CPAN.
64Distributions on CPAN which require these modules will need to list them as
65prerequisites.
df758df2 66
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67The core versions of these modules will now issue C<"deprecated">-category
68warnings to alert you to this fact. To silence these deprecation warnings,
69install the modules in question from CPAN.
412f55bb 70
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71Note that these are (with rare exceptions) fine modules that you are encouraged
72to continue to use. Their disinclusion from core primarily hinges on their
73necessity to bootstrapping a fully functional, CPAN-capable Perl installation,
74not usually on concerns over their design.
412f55bb 75
13900f93 76=over
7065301c 77
13900f93 78=item XXX
7065301c 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.
d133a3dd 82
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83=back
84
85[ List each other deprecation as a =head2 entry ]
86
87=head1 Performance Enhancements
88
89XXX Changes which enhance performance without changing behaviour go here.
90There may well be none in a stable release.
91
92[ List each enhancement as a =item entry ]
93
94=over 4
7065301c 95
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96=item *
97
13900f93 98XXX
6bb82be0 99
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100=back
101
7ef8b31d 102=head1 Modules and Pragmata
f6f3144e 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>. A paragraph summary
107for important changes should then be added by hand. In an ideal world,
108dual-life modules would have a F<Changes> file that could be cribbed.
2fc36bac 109
13900f93 110[ Within each section, list entries as a =item entry ]
2fc36bac 111
13900f93 112=head2 New Modules and Pragmata
2fc36bac 113
13900f93 114=over 4
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115
116=item *
117
13900f93 118XXX
7065301c 119
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120=back
121
122=head2 Updated Modules and Pragmata
7065301c 123
13900f93 124=over 4
7065301c 125
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126=item *
127
830fa6b6 128L<B::Debug> has been upgraded from version 1.19 to 1.21
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129
130=item *
131
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132L<Config::Perl::V> has been upgraded from version 0.20 to 0.22.
133
134=item *
135
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136L<CPAN::Meta> has been upgraded from version 2.141520 to 2.142060.
137
138=item *
139
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140L<CPAN::Meta::Requirements> has been upgraded from version 2.125 to 2.126.
141
142=item *
143
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144L<ExtUtils::Manifest> has been upgraded from version 1.64 to 1.65.
145
146The MANIFEST is now opened with C<:raw>, to prevent C<CRLF>s leaking in.
147
148=item *
149
796f59e8 150L<perl5db.pl> has been upgraded from version 1.45 to 1.46.
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151
152Fixed the scope level handling of the debugger's C<y> command.
aac7f82f 153
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154=item *
155
156L<POSIX> has been upgraded from version 1.41 to 1.42.
157
158Replaced the thread-unsafe code used to prevent duplicate warning
159messages for using the isxxx() functions. [perl #122476]
160
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161=item *
162
163L<Socket> has been upgraded from version 2.014 to 2.015.
164
165Test suite updates, particularly useful for Solaris and cygwin, and
166a slight change to the pattern used for IPv4 address matching.
167
13900f93 168=back
aac7f82f 169
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170=head2 Removed Modules and Pragmata
171
172=over 4
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173
174=item *
175
13900f93 176XXX
aac7f82f 177
13900f93 178=back
aac7f82f 179
13900f93 180=head1 Documentation
aac7f82f 181
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182XXX Changes to files in F<pod/> go here. Consider grouping entries by
183file and be sure to link to the appropriate page, e.g. L<perlfunc>.
aac7f82f 184
13900f93 185=head2 New Documentation
7065301c 186
13900f93 187XXX Changes which create B<new> files in F<pod/> go here.
7065301c 188
13900f93 189=head3 L<XXX>
aac7f82f 190
13900f93 191XXX Description of the purpose of the new file here
aac7f82f 192
13900f93 193=head2 Changes to Existing Documentation
6d9b7c7c 194
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195XXX Changes which significantly change existing files in F<pod/> go here.
196However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
197section.
6d9b7c7c 198
13900f93 199=head3 L<XXX>
7f55cec0 200
13900f93 201=over 4
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202
203=item *
204
13900f93 205XXX Description of the change here
aac7f82f 206
13900f93 207=back
aac7f82f 208
13900f93 209=head1 Diagnostics
091fed7c 210
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211The following additions or changes have been made to diagnostic output,
212including warnings and fatal error messages. For the complete list of
213diagnostic messages, see L<perldiag>.
902c1f75 214
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215XXX New or changed warnings emitted by the core's C<C> code go here. Also
216include any changes in L<perldiag> that reconcile it to the C<C> code.
2901561d 217
13900f93 218=head2 New Diagnostics
2901561d 219
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220XXX Newly added diagnostic messages go under here, separated into New Errors
221and New Warnings
222
223=head3 New Errors
4594cf53 224
13900f93 225=over 4
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226
227=item *
228
13900f93 229XXX L<message|perldiag/"message">
7065301c 230
13900f93 231=back
58f25ac1 232
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233=head3 New Warnings
234
235=over 4
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236
237=item *
238
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239L<Hexadecimal float: exponent overflow|perldiag/"Hexadecimal float: exponent overflow">
240
241(W overflow) The hexadecimal floating point has larger exponent
242than the floating point supports.
243
244=item *
245
246L<Hexadecimal float: exponent underflow|perldiag/"Hexadecimal float: exponent underflow">
247
248(W overflow) The hexadecimal floating point has smaller exponent
249than the floating point supports.
250
251=item *
252
253L<Hexadecimal float: internal error|perldiag/"Hexadecimal float: internal error">
254
255(F) Something went horribly bad in hexadecimal float handling.
256
257=item *
258
259L<Hexadecimal float: mantissa overflow|perldiag/"Hexadecimal float: mantissa overflow">
260
261(W overflow) The hexadecimal floating point literal had more bits in
262the mantissa (the part between the 0x and the exponent, also known as
263the fraction or the significand) than the floating point supports.
264
265=item *
266
267L<Hexadecimal float: precision loss|perldiag/"Hexadecimal float: precision loss">
268
269(W overflow) The hexadecimal floating point had internally more
270digits than could be output. This can be caused by unsupported
271long double formats, or by 64-bit integers not being available
272(needed to retrieve the digits under some configurations).
273
274=item *
275
276L<Hexadecimal float: unsupported long double format|perldiag/"Hexadecimal float: unsupported long double format">
277
278(F) You have configured Perl to use long doubles but
279the internals of the long double format are unknown,
280therefore the hexadecimal float output is impossible.
5bafdaa4 281
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282=back
283
13900f93 284=head2 Changes to Existing Diagnostics
12042f24 285
13900f93 286XXX Changes (i.e. rewording) of diagnostic messages go here
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287
288=over 4
289
290=item *
291
13900f93 292XXX Describe change here
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293
294=back
295
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296=head1 Utility Changes
297
298XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go here.
299Most of these are built within the directory F<utils>.
300
301[ List utility changes as a =head2 entry for each utility and =item
302entries for each change
303Use L<XXX> with program names to get proper documentation linking. ]
304
305=head2 L<XXX>
7065301c 306
6d9b7c7c 307=over 4
7065301c 308
6d9b7c7c 309=item *
0346c3a9 310
13900f93 311XXX
7065301c 312
6d9b7c7c 313=back
0346c3a9 314
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315=head1 Configuration and Compilation
316
317XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
318go here. Any other changes to the Perl build process should be listed here.
319However, any platform-specific changes should be listed in the
320L</Platform Support> section, instead.
321
322[ List changes as a =item entry ].
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323
324=over 4
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325
326=item *
327
a5873648 328Internal handling of floating point values has been improved.
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329
330=back
331
13900f93 332=head1 Testing
6d9b7c7c 333
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334XXX Any significant changes to the testing of a freshly built perl should be
335listed here. Changes which create B<new> files in F<t/> go here as do any
336large changes to the testing harness (e.g. when parallel testing was added).
337Changes to existing files in F<t/> aren't worth summarizing, although the bugs
338that they represent may be covered elsewhere.
6d9b7c7c 339
13900f93 340[ List each test improvement as a =item entry ]
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341
342=over 4
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343
344=item *
345
13900f93 346XXX
48867f3d 347
13900f93 348=back
28462159 349
13900f93 350=head1 Platform Support
097675bf 351
13900f93 352XXX Any changes to platform support should be listed in the sections below.
b3211734 353
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354[ Within the sections, list each platform as a =item entry with specific
355changes as paragraphs below it. ]
b3211734 356
13900f93 357=head2 New Platforms
24a38d90 358
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359XXX List any platforms that this version of perl compiles on, that previous
360versions did not. These will either be enabled by new files in the F<hints/>
361directories, or new subdirectories and F<README> files at the top level of the
362source tree.
b08d439a 363
0346c3a9 364=over 4
747b6130 365
13900f93 366=item XXX-some-platform
747b6130 367
13900f93 368XXX
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369
370=back
371
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372=head2 Discontinued Platforms
373
374XXX List any platforms that this version of perl no longer compiles on.
0346c3a9 375
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376=over 4
377
13900f93 378=item XXX-some-platform
24a38d90 379
13900f93 380XXX
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381
382=back
383
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384=head2 Platform-Specific Notes
385
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386XXX List any changes for specific platforms. This could include configuration
387and compilation changes or changes in portability/compatibility. However,
388changes within modules for platforms should generally be listed in the
389L</Modules and Pragmata> section.
390
0346c3a9 391=over 4
7d0ccdba 392
13900f93 393=item XXX-some-platform
7d0ccdba 394
13900f93 395XXX
7d0ccdba 396
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397=back
398
399=head1 Internal Changes
400
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401XXX Changes which affect the interface available to C<XS> code go here. Other
402significant internal changes for future core maintainers should be noted as
403well.
c9fcb674 404
13900f93 405[ List each change as a =item entry ]
ddeaf645 406
13900f93 407=over 4
c9fcb674 408
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409=item *
410
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411Added L<perlapi/sync_locale>.
412Changing the program's locale should be avoided by XS code. Nevertheless,
413certain non-Perl libraries called from XS, such as C<Gtk> do so. When this
414happens, Perl needs to be told that the locale has changed. Use this function
415to do so, before returning to Perl.
c1284011 416
6d9b7c7c 417=back
c1284011 418
6d9b7c7c 419=head1 Selected Bug Fixes
375f5f06 420
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421XXX Important bug fixes in the core language are summarized here. Bug fixes in
422files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
423
424[ List each fix as a =item entry ]
425
0346c3a9 426=over 4
375f5f06 427
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428=item *
429
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430Failing to compile C<use Foo> in an eval could leave a spurious
431C<BEGIN> subroutine definition, which would produce a "Subroutine
432BEGIN redefined" warning on the next use of C<use>, or other C<BEGIN>
433block. [perl #122107]
2884baee 434
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435=item *
436
437C<method { BLOCK } ARGS> syntax now correctly parses the arguments if they
438begin with an opening brace. [perl #46947]
439
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440=back
441
442=head1 Known Problems
443
444XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
445tests that had to be C<TODO>ed for the release would be noted here. Unfixed
446platform specific bugs also go here.
5af51eb4 447
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448[ List each fix as a =item entry ]
449
450=over 4
5af51eb4 451
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452=item *
453
13900f93 454XXX
412f55bb 455
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456=back
457
13900f93 458=head1 Errata From Previous Releases
24a38d90 459
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460=over 4
461
462=item *
e831f11a 463
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464XXX Add anything here that we forgot to add, or were mistaken about, in
465the perldelta of a previous release.
e831f11a 466
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467=back
468
469=head1 Obituary
e831f11a 470
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471XXX If any significant core contributor has died, we've added a short obituary
472here.
e831f11a 473
13900f93 474=head1 Acknowledgements
e831f11a 475
13900f93 476XXX Generate this with:
e831f11a 477
13900f93 478 perl Porting/acknowledgements.pl v5.21.2..HEAD
f5b73711 479
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480=head1 Reporting Bugs
481
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482If you find what you think is a bug, you might check the articles recently
483posted to the comp.lang.perl.misc newsgroup and the perl bug database at
238894db 484https://rt.perl.org/ . There may also be information at
7ef8b31d 485http://www.perl.org/ , the Perl Home Page.
44691e6f 486
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487If you believe you have an unreported bug, please run the L<perlbug> program
488included with your release. Be sure to trim your bug down to a tiny but
489sufficient test case. Your bug report, along with the output of C<perl -V>,
490will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
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491
492If the bug you are reporting has security implications, which make it
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493inappropriate to send to a publicly archived mailing list, then please send it
494to perl5-security-report@perl.org. This points to a closed subscription
495unarchived mailing list, which includes all the core committers, who will be
496able to help assess the impact of issues, figure out a resolution, and help
f9001595 497co-ordinate the release of patches to mitigate or fix the problem across all
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498platforms on which Perl is supported. Please only use this address for
499security issues in the Perl core, not for modules independently distributed on
500CPAN.
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501
502=head1 SEE ALSO
503
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504The F<Changes> file for an explanation of how to view exhaustive details on
505what changed.
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506
507The F<INSTALL> file for how to build Perl.
508
509The F<README> file for general stuff.
510
511The F<Artistic> and F<Copying> files for copyright information.
512
513=cut