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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 v5.21.10
c68523cb 9
238894db 10=head1 DESCRIPTION
c68523cb 11
a9c3e753 12This document describes differences between the 5.21.9 release and the 5.21.10
238894db 13release.
c68523cb 14
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15If you are upgrading from an earlier release such as 5.21.8, first read
16L<perl5219delta>, which describes differences between 5.21.8 and 5.21.9.
2ec11c70 17
b5d4d3b9 18=head1 Notice
2ec11c70 19
a9c3e753 20XXX Any important notices here
67f2cc75 21
b5d4d3b9 22=head1 Core Enhancements
67f2cc75 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.
06ae2722 27
a9c3e753 28[ List each enhancement as a =head2 entry ]
156f41cf 29
a9c3e753 30=head1 Security
156f41cf 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.
156f41cf 35
a9c3e753 36[ List each security issue as a =head2 entry ]
48c4d243 37
b5d4d3b9 38=head1 Incompatible Changes
ef8784b7 39
a9c3e753 40XXX For a release on a stable branch, this section aspires to be:
541e1e0d 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.
541e1e0d 45
a9c3e753 46[ List each incompatible change as a =head2 entry ]
541e1e0d 47
a9c3e753 48=head1 Deprecations
541e1e0d 49
a9c3e753 50XXX Any deprecated features, syntax, modules etc. should be listed here.
541e1e0d 51
a9c3e753 52=head2 Module removals
541e1e0d 53
a9c3e753 54XXX Remove this section if inapplicable.
541e1e0d 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.
cd7bac54 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.
541e1e0d 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.
541e1e0d 69
a9c3e753 70=over
cd7bac54 71
a9c3e753 72=item XXX
6c8457e9 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.
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76
77=back
6c8457e9 78
a9c3e753 79[ List each other deprecation as a =head2 entry ]
6c8457e9 80
a9c3e753 81=head1 Performance Enhancements
6c8457e9 82
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83XXX Changes which enhance performance without changing behaviour go here.
84There may well be none in a stable release.
127a7155 85
a9c3e753 86[ List each enhancement as a =item entry ]
6c8457e9 87
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88=over 4
89
90=item *
91
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92The functions
93C<utf8::native_to_unicode()> and
94C<utf8::unicode_to_native()> (see L<utf8>)
95are now optimized out on ASCII platforms.
96There is now not even a minimal performance hit in writing code portable
97between ASCII and EBCDIC platforms.
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98
99=back
100
a9c3e753 101=head1 Modules and Pragmata
0939a951 102
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103XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
104go here. If Module::CoreList is updated, generate an initial draft of the
105following sections using F<Porting/corelist-perldelta.pl>. A paragraph summary
106for important changes should then be added by hand. In an ideal world,
107dual-life modules would have a F<Changes> file that could be cribbed.
c49582c3 108
a9c3e753 109[ Within each section, list entries as a =item entry ]
9024667a 110
a9c3e753 111=head2 New Modules and Pragmata
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112
113=over 4
114
115=item *
116
a9c3e753 117XXX
0ce5e53e 118
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119=back
120
a9c3e753 121=head2 Updated Modules and Pragmata
cd7bac54 122
a9c3e753 123=over 4
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124
125=item *
126
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127L<B> has been upgraded from version 1.56 to 1.57.
128
129=item *
130
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131L<B::Deparse> has been upgraded from version 1.33 to 1.34.
132
133Deparse C<$#_> as that instead of as C<$#{_}>. [perl #123947]
134
135=item *
136
d210e520 137L<CPAN> has been upgraded from version 2.05 to 2.10.
79116533
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138
139=over 4
140
141=item *
142
143Add support for C<Cwd::getdcwd()> and introduce workaround for a misbehaviour
144seen on Strawberry Perl 5.20.1.
145
146=item *
147
148Fix C<chdir()> after building dependencies bug.
149
150=item *
151
152Introduce experimental support for plugins/hooks.
153
154=item *
155
156Integrate the App::Cpan sources.
157
158=item *
159
160Do not check recursion on optional dependencies.
161
162=item *
163
164Sanity check META.yml to contain a hash.
165L<[cpan #95271]|https://rt.cpan.org/Ticket/Display.html?id=95271>
166
167=back
0939a951 168
c0ff9143
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169=item *
170
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171L<CPAN::Meta> has been upgraded from version 2.143240 to 2.150001.
172
173=item *
174
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175L<Data::Dumper> has been upgraded from version 2.157 to 2.158.
176
177=item *
178
179L<DynaLoader> has been upgraded from version 1.31 to 1.32.
180
181=item *
182
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183L<Encode> has been upgraded from version 2.70 to 2.72.
184
185=item *
186
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187L<encoding> has been upgraded from version 2.13 to 2.14.
188
189=item *
190
191L<Getopt::Long> has been upgraded from version 2.43 to 2.45.
192
193=item *
194
195L<locale> has been upgraded from version 1.05 to 1.06.
196
197=item *
198
199L<Locale::Codes> has been upgraded from version 3.33 to 3.34.
200
201=item *
202
203L<Module::CoreList> has been reverted from version 5.20150220 to 5.20150320.
204
205=item *
206
207L<Pod::Functions> has been upgraded from version 1.08 to 1.09.
208
209=item *
210
211L<POSIX> has been upgraded from version 1.51 to 1.52.
212
213=item *
214
215L<re> has been upgraded from version 0.31 to 0.32.
216
217=item *
218
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219L<Test::Simple> has been reverted from version 1.301001_098 to 1.001014.
220
221=item *
222
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223L<Text::Balanced> has been upgraded from version 2.02 to 2.03.
224
225No changes to installed files other than the version bump.
226
227=item *
228
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229L<Text::ParseWords> has been upgraded from version 3.29 to 3.30.
230
231=item *
232
15af3bc0 233L<threads> has been upgraded from version 1.96_001 to 2.01.
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234
235=item *
236
237L<utf8> has been upgraded from version 1.14 to 1.15.
238
239=item *
240
241L<XS::APItest> has been upgraded from version 0.70 to 0.71.
c0ff9143 242
a9c3e753 243=back
0939a951 244
a9c3e753 245=head2 Removed Modules and Pragmata
cd7bac54 246
a9c3e753 247=over 4
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248
249=item *
250
a9c3e753 251XXX
cd7bac54 252
2ff1ebfe 253=back
541e1e0d 254
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255=head1 Documentation
256
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257XXX Changes to files in F<pod/> go here. Consider grouping entries by
258file and be sure to link to the appropriate page, e.g. L<perlfunc>.
259
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260=head2 New Documentation
261
a9c3e753 262XXX Changes which create B<new> files in F<pod/> go here.
541e1e0d 263
a9c3e753 264=head3 L<XXX>
d676fe86 265
a9c3e753 266XXX Description of the purpose of the new file here
d676fe86 267
a9c3e753 268=head2 Changes to Existing Documentation
d2fff9f6 269
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270XXX Changes which significantly change existing files in F<pod/> go here.
271However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
272section.
d2fff9f6 273
83a5d6b6 274=head3 L<perldata>
e329daf3 275
cd7bac54 276=over 4
e329daf3 277
cd7bac54 278=item *
e329daf3 279
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280Documentation has been added regarding the special floating point values C<Inf>
281and C<NaN>.
282
283=back
284
285=head3 L<perlexperiment>
286
287=over 4
288
289=item *
290
291Removed note about C<\s> matching C<VT> now that it is no longer experimental.
292
293=item *
294
295Added note that C<use re 'strict'> has been introduced experimentally.
296
297=back
298
299=head3 L<perlpolicy>
300
301=over 4
302
303=item *
304
305The documentation of what to expect to see in future maintenance releases has
306been updated. Essentially the same types of changes will be included as before
307but with fewer changes that don't affect the installation or execution of perl.
ba31029d 308
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309=back
310
a9c3e753 311=head1 Diagnostics
cd7bac54 312
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313The following additions or changes have been made to diagnostic output,
314including warnings and fatal error messages. For the complete list of
315diagnostic messages, see L<perldiag>.
cd7bac54 316
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317XXX New or changed warnings emitted by the core's C<C> code go here. Also
318include any changes in L<perldiag> that reconcile it to the C<C> code.
cd7bac54 319
a9c3e753 320=head2 New Diagnostics
541e1e0d 321
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322XXX Newly added diagnostic messages go under here, separated into New Errors
323and New Warnings
541e1e0d 324
a9c3e753 325=head3 New Errors
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326
327=over 4
328
329=item *
330
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331L<Invalid quantifier in {,} in regex; marked by <-- HERE in mE<sol>%sE<sol>|perldiag/"Invalid quantifier in {,} in regex; marked by <-- HERE in m/%s/">
332
333(F) The pattern looks like a {min,max} quantifier, but the min or max could not
334be parsed as a valid number - either it has leading zeroes, or it represents
335too big a number to cope with. The S<<-- HERE> shows where in the regular
336expression the problem was discovered. See L<perlre>.
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337
338=back
541e1e0d 339
a9c3e753 340=head3 New Warnings
541e1e0d 341
2ff1ebfe 342=over 4
aa67537d 343
4c7a0d98
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344=item *
345
a9c3e753 346XXX L<message|perldiag/"message">
4c7a0d98 347
b5d4d3b9 348=back
4c7a0d98 349
a9c3e753 350=head2 Changes to Existing Diagnostics
a5d66edf 351
a9c3e753 352XXX Changes (i.e. rewording) of diagnostic messages go here
f348c3d8 353
cd7bac54 354=over 4
f348c3d8 355
cd7bac54 356=item *
2ff1ebfe 357
a9c3e753 358XXX Describe change here
f348c3d8 359
cd7bac54 360=back
2ff1ebfe 361
a9c3e753 362=head1 Utility Changes
f348c3d8 363
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364XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go here.
365Most of these are built within the directory F<utils>.
4dc623f0 366
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367[ List utility changes as a =head2 entry for each utility and =item
368entries for each change
369Use L<XXX> with program names to get proper documentation linking. ]
84d03adf 370
a9c3e753 371=head2 L<XXX>
ff433f2d 372
9ce6583e 373=over 4
4cd408ba 374
9ce6583e 375=item *
6ed80d55 376
a9c3e753 377XXX
9ce6583e 378
2ff1ebfe 379=back
ab0b796c 380
a9c3e753 381=head1 Configuration and Compilation
cd7bac54 382
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383XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
384go here. Any other changes to the Perl build process should be listed here.
385However, any platform-specific changes should be listed in the
386L</Platform Support> section, instead.
cd7bac54 387
a9c3e753 388[ List changes as a =item entry ].
8c6180a9 389
2ff1ebfe 390=over 4
0561e60b 391
9ce6583e 392=item *
dd200dff 393
a9c3e753 394XXX
c877af1b 395
cd7bac54 396=back
c877af1b 397
a9c3e753 398=head1 Testing
cd7bac54 399
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400XXX Any significant changes to the testing of a freshly built perl should be
401listed here. Changes which create B<new> files in F<t/> go here as do any
402large changes to the testing harness (e.g. when parallel testing was added).
403Changes to existing files in F<t/> aren't worth summarizing, although the bugs
404that they represent may be covered elsewhere.
cd7bac54 405
a9c3e753 406[ List each test improvement as a =item entry ]
bb8c7e27 407
b5d4d3b9 408=over 4
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409
410=item *
411
83a5d6b6 412Tests for performance issues have been added in the file F<t/perf/taint.t>.
13adb056 413
b5d4d3b9 414=back
391823f2 415
a9c3e753 416=head1 Platform Support
6c8457e9 417
a9c3e753 418XXX Any changes to platform support should be listed in the sections below.
6c8457e9 419
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420[ Within the sections, list each platform as a =item entry with specific
421changes as paragraphs below it. ]
db98db4e 422
a9c3e753 423=head2 New Platforms
8818afe8 424
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425XXX List any platforms that this version of perl compiles on, that previous
426versions did not. These will either be enabled by new files in the F<hints/>
427directories, or new subdirectories and F<README> files at the top level of the
428source tree.
8af808bf 429
2ff1ebfe 430=over 4
fdcaecb7 431
a9c3e753 432=item XXX-some-platform
fdcaecb7 433
a9c3e753 434XXX
2af7c6b6 435
4dc623f0 436=back
2af7c6b6 437
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438=head2 Discontinued Platforms
439
440XXX List any platforms that this version of perl no longer compiles on.
70cee83f 441
b5d4d3b9 442=over 4
e5fbfbc1 443
a9c3e753 444=item XXX-some-platform
b4045391 445
a9c3e753 446XXX
b4045391 447
2ff1ebfe 448=back
b4045391 449
2ff1ebfe 450=head2 Platform-Specific Notes
8c847e66 451
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452XXX List any changes for specific platforms. This could include configuration
453and compilation changes or changes in portability/compatibility. However,
454changes within modules for platforms should generally be listed in the
455L</Modules and Pragmata> section.
8c847e66 456
2ff1ebfe 457=over 4
d345f487 458
a9c3e753 459=item XXX-some-platform
d345f487 460
a9c3e753 461XXX
cd7bac54 462
4dc623f0 463=back
353075a0 464
a9c3e753 465=head1 Internal Changes
9f122eef 466
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467XXX Changes which affect the interface available to C<XS> code go here. Other
468significant internal changes for future core maintainers should be noted as
469well.
2ff1ebfe 470
a9c3e753 471[ List each change as a =item entry ]
2ff1ebfe 472
b5d4d3b9 473=over 4
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474
475=item *
476
a9c3e753 477XXX
2683609f 478
4dc623f0 479=back
c7f058f0 480
4dc623f0 481=head1 Selected Bug Fixes
0ef4323a 482
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483XXX Important bug fixes in the core language are summarized here. Bug fixes in
484files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
567291b6 485
a9c3e753 486[ List each fix as a =item entry ]
436f6503 487
a9c3e753 488=over 4
2bf83140 489
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490=item *
491
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492Repeated global pattern matches in scalar context on large tainted
493strings were exponentially slow depending on the current match
494position in the string. [perl #123202]
041a5927 495
a9c3e753 496=back
ea13b07e 497
a9c3e753 498=head1 Known Problems
b65adbec 499
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500XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
501tests that had to be C<TODO>ed for the release would be noted here. Unfixed
502platform specific bugs also go here.
b65adbec 503
a9c3e753 504[ List each fix as a =item entry ]
370c71c5 505
a9c3e753 506=over 4
b94c7836
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507
508=item *
509
a9c3e753 510XXX
439f6100 511
a9c3e753 512=back
e3e8f263 513
a9c3e753 514=head1 Errata From Previous Releases
cd7bac54 515
a9c3e753 516=over 4
e3e8f263 517
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518=item *
519
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520XXX Add anything here that we forgot to add, or were mistaken about, in
521the perldelta of a previous release.
cb6cc22b 522
b5d4d3b9 523=back
fcfb7b86 524
a9c3e753 525=head1 Obituary
cd7bac54 526
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527XXX If any significant core contributor has died, we've added a short obituary
528here.
cd7bac54 529
a9c3e753 530=head1 Acknowledgements
541e1e0d 531
a9c3e753 532XXX Generate this with:
01d42a22 533
a9c3e753 534 perl Porting/acknowledgements.pl v5.21.9..HEAD
f5b73711 535
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536=head1 Reporting Bugs
537
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538If you find what you think is a bug, you might check the articles recently
539posted to the comp.lang.perl.misc newsgroup and the perl bug database at
238894db 540https://rt.perl.org/ . There may also be information at
7ef8b31d 541http://www.perl.org/ , the Perl Home Page.
44691e6f 542
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543If you believe you have an unreported bug, please run the L<perlbug> program
544included with your release. Be sure to trim your bug down to a tiny but
545sufficient test case. Your bug report, along with the output of C<perl -V>,
546will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
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547
548If the bug you are reporting has security implications, which make it
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549inappropriate to send to a publicly archived mailing list, then please send it
550to perl5-security-report@perl.org. This points to a closed subscription
551unarchived mailing list, which includes all the core committers, who will be
552able to help assess the impact of issues, figure out a resolution, and help
f9001595 553co-ordinate the release of patches to mitigate or fix the problem across all
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554platforms on which Perl is supported. Please only use this address for
555security issues in the Perl core, not for modules independently distributed on
556CPAN.
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557
558=head1 SEE ALSO
559
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560The F<Changes> file for an explanation of how to view exhaustive details on
561what changed.
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562
563The F<INSTALL> file for how to build Perl.
564
565The F<README> file for general stuff.
566
567The F<Artistic> and F<Copying> files for copyright information.
568
569=cut