5 [ this is a template for a new perldelta file. Any text flagged as XXX needs
6 to be processed before release. ]
8 perldelta - what is new for perl v5.29.9
12 This document describes differences between the 5.29.8 release and the 5.29.9
15 If you are upgrading from an earlier release such as 5.29.7, first read
16 L<perl5298delta>, which describes differences between 5.29.7 and 5.29.8.
20 XXX Any important notices here
22 =head1 Core Enhancements
24 XXX New core language features go here. Summarize user-visible core language
25 enhancements. Particularly prominent performance optimisations could go
26 here, but most should go in the L</Performance Enhancements> section.
28 [ List each enhancement as a =head2 entry ]
30 =head2 Unicode 12.0 is supported
32 For details, see L<https://www.unicode.org/versions/Unicode12.0.0/>.
34 Because of a change in Unicode release cycles, Perl jumps from Unicode
35 10.0 in Perl 5.28 to Unicode 12.0 in Perl 5.30.
37 =head2 It is now possible to compile perl to always use thread-safe
40 Previously, these calls were only used when the perl was compiled to be
41 multi-threaded. To always enable them, add
43 -Accflags='-DUSE_THREAD_SAFE_LOCALE'
45 to your F<Configure> flags.
50 XXX Any security-related notices go here. In particular, any security
51 vulnerabilities closed should be noted here rather than in the
52 L</Selected Bug Fixes> section.
54 [ List each security issue as a =head2 entry ]
56 =head1 Incompatible Changes
58 XXX For a release on a stable branch, this section aspires to be:
60 There are no changes intentionally incompatible with 5.XXX.XXX
61 If any exist, they are bugs, and we request that you submit a
62 report. See L</Reporting Bugs> below.
64 [ List each incompatible change as a =head2 entry ]
66 =head2 C<pack()> no longer can return malformed UTF-8
68 It croaks if it would otherwise return a UTF-8 string that contains
69 malformed UTF-8. This protects agains potential security threats. This
70 is considered a bug fix as well ([perl #131642]).
74 XXX Any deprecated features, syntax, modules etc. should be listed here.
76 =head2 Module removals
78 XXX Remove this section if not applicable.
80 The following modules will be removed from the core distribution in a
81 future release, and will at that time need to be installed from CPAN.
82 Distributions on CPAN which require these modules will need to list them as
85 The core versions of these modules will now issue C<"deprecated">-category
86 warnings to alert you to this fact. To silence these deprecation warnings,
87 install the modules in question from CPAN.
89 Note that these are (with rare exceptions) fine modules that you are encouraged
90 to continue to use. Their disinclusion from core primarily hinges on their
91 necessity to bootstrapping a fully functional, CPAN-capable Perl installation,
92 not usually on concerns over their design.
98 XXX Note that deprecated modules should be listed here even if they are listed
99 as an updated module in the L</Modules and Pragmata> section.
103 [ List each other deprecation as a =head2 entry ]
105 =head1 Performance Enhancements
107 XXX Changes which enhance performance without changing behaviour go here.
108 There may well be none in a stable release.
110 [ List each enhancement as an =item entry ]
120 =head1 Modules and Pragmata
122 XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
123 go here. If Module::CoreList is updated, generate an initial draft of the
124 following sections using F<Porting/corelist-perldelta.pl>. A paragraph summary
125 for important changes should then be added by hand. In an ideal world,
126 dual-life modules would have a F<Changes> file that could be cribbed.
128 The list of new and updated modules is modified automatically as part of
129 preparing a Perl release, so the only reason to manually add entries here is if
130 you're summarising the important changes in the module update. (Also, if the
131 manually-added details don't match the automatically-generated ones, the
132 release manager will have to investigate the situation carefully.)
134 [ Within each section, list entries as an =item entry ]
136 =head2 New Modules and Pragmata
142 XXX Remove this section if not applicable.
146 =head2 Updated Modules and Pragmata
152 L<perl5db.pl> has been upgraded from version 1.54 to 1.55.
154 Debugging threaded code no longer deadlocks in C<DB::sub> nor
159 L<PerlIO::encoding> has been upgraded from version 0.26 to 0.27.
161 Warnings enabled by setting the C<WARN_ON_ERR> flag in
162 C<$PerlIO::encoding::fallback> are now only produced if warnings are
163 enabled with C<use warnings "utf8";> or setting C<$^W>.
167 L<threads::shared> has been upgraded from version 1.59 to 1.60.
169 Added support for extra tracing of locking, this requires a
170 C<-DDEBUGGING> and extra compilation flags.
174 =head2 Removed Modules and Pragmata
186 XXX Changes to files in F<pod/> go here. Consider grouping entries by
187 file and be sure to link to the appropriate page, e.g. L<perlfunc>.
189 =head2 New Documentation
191 XXX Changes which create B<new> files in F<pod/> go here.
195 XXX Description of the purpose of the new file here
197 =head2 Changes to Existing Documentation
199 We have attempted to update the documentation to reflect the changes
200 listed in this document. If you find any we have missed, send email
201 to L<perlbug@perl.org|mailto:perlbug@perl.org>.
203 XXX Changes which significantly change existing files in F<pod/> go here.
204 However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
207 Additionally, the following selected changes have been made:
215 XXX Description of the change here
221 The following additions or changes have been made to diagnostic output,
222 including warnings and fatal error messages. For the complete list of
223 diagnostic messages, see L<perldiag>.
225 XXX New or changed warnings emitted by the core's C<C> code go here. Also
226 include any changes in L<perldiag> that reconcile it to the C<C> code.
228 =head2 New Diagnostics
230 XXX Newly added diagnostic messages go under here, separated into New Errors
239 XXX L<message|perldiag/"message">
249 XXX L<message|perldiag/"message">
253 =head2 Changes to Existing Diagnostics
255 XXX Changes (i.e. rewording) of diagnostic messages go here
261 XXX Describe change here
265 =head1 Utility Changes
267 XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go here.
268 Most of these are built within the directory F<utils>.
270 [ List utility changes as a =head2 entry for each utility and =item
271 entries for each change
272 Use L<XXX> with program names to get proper documentation linking. ]
284 =head1 Configuration and Compilation
286 XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
287 go here. Any other changes to the Perl build process should be listed here.
288 However, any platform-specific changes should be listed in the
289 L</Platform Support> section, instead.
291 [ List changes as an =item entry ].
303 XXX Any significant changes to the testing of a freshly built perl should be
304 listed here. Changes which create B<new> files in F<t/> go here as do any
305 large changes to the testing harness (e.g. when parallel testing was added).
306 Changes to existing files in F<t/> aren't worth summarizing, although the bugs
307 that they represent may be covered elsewhere.
309 XXX If there were no significant test changes, say this:
311 Tests were added and changed to reflect the other additions and changes
314 XXX If instead there were significant changes, say this:
316 Tests were added and changed to reflect the other additions and
317 changes in this release. Furthermore, these significant changes were
320 [ List each test improvement as an =item entry ]
330 =head1 Platform Support
332 XXX Any changes to platform support should be listed in the sections below.
334 [ Within the sections, list each platform as an =item entry with specific
335 changes as paragraphs below it. ]
339 XXX List any platforms that this version of perl compiles on, that previous
340 versions did not. These will either be enabled by new files in the F<hints/>
341 directories, or new subdirectories and F<README> files at the top level of the
346 =item XXX-some-platform
352 =head2 Discontinued Platforms
354 XXX List any platforms that this version of perl no longer compiles on.
358 =item XXX-some-platform
364 =head2 Platform-Specific Notes
366 XXX List any changes for specific platforms. This could include configuration
367 and compilation changes or changes in portability/compatibility. However,
368 changes within modules for platforms should generally be listed in the
369 L</Modules and Pragmata> section.
373 =item XXX-some-platform
379 =head1 Internal Changes
381 XXX Changes which affect the interface available to C<XS> code go here. Other
382 significant internal changes for future core maintainers should be noted as
385 [ List each change as an =item entry ]
391 Added C<newSVsv_nomg()> to copy a SV without processing get magic on
392 the source. [perl #132964]
396 =head1 Selected Bug Fixes
398 XXX Important bug fixes in the core language are summarized here. Bug fixes in
399 files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
401 [ List each fix as an =item entry ]
407 C<pack()> no longer can return malformed UTF-8. It croaks if it would
408 otherwise return a UTF-8 string that contains malformed UTF-8. This
409 protects agains potential security threats. [perl #131642]
413 =head1 Known Problems
415 XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
416 tests that had to be C<TODO>ed for the release would be noted here. Unfixed
417 platform specific bugs also go here.
419 [ List each fix as an =item entry ]
429 =head1 Errata From Previous Releases
435 XXX Add anything here that we forgot to add, or were mistaken about, in
436 the perldelta of a previous release.
442 XXX If any significant core contributor or member of the CPAN community has
443 died, add a short obituary here.
445 =head1 Acknowledgements
447 XXX Generate this with:
449 perl Porting/acknowledgements.pl v5.29.8..HEAD
451 =head1 Reporting Bugs
453 If you find what you think is a bug, you might check the perl bug database
454 at L<https://rt.perl.org/>. There may also be information at
455 L<http://www.perl.org/>, the Perl Home Page.
457 If you believe you have an unreported bug, please run the L<perlbug> program
458 included with your release. Be sure to trim your bug down to a tiny but
459 sufficient test case. Your bug report, along with the output of C<perl -V>,
460 will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
462 If the bug you are reporting has security implications which make it
463 inappropriate to send to a publicly archived mailing list, then see
464 L<perlsec/SECURITY VULNERABILITY CONTACT INFORMATION>
465 for details of how to report the issue.
469 If you wish to thank the Perl 5 Porters for the work we had done in Perl 5,
470 you can do so by running the C<perlthanks> program:
474 This will send an email to the Perl 5 Porters list with your show of thanks.
478 The F<Changes> file for an explanation of how to view exhaustive details on
481 The F<INSTALL> file for how to build Perl.
483 The F<README> file for general stuff.
485 The F<Artistic> and F<Copying> files for copyright information.