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 v5.19.3
12 This document describes differences between the 5.19.2 release and the 5.19.3
15 If you are upgrading from an earlier release such as 5.19.1, first read
16 L<perl5192delta>, which describes differences between 5.19.1 and 5.19.2.
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 B<-F> now implies B<-a> and B<-a> implies B<-n>
32 Previously B<-F> without B<-a> was a no-op, and B<-a> without B<-n> or
33 B<-p> was a no-op, with this change, if you supply B<-F> then both
34 B<-a> and B<-n> are implied and if you supply B<-a> then B<-n> is implied.
36 You can still use B<-p> for its extra behaviour. [perl #116190]
40 XXX Any security-related notices go here. In particular, any security
41 vulnerabilities closed should be noted here rather than in the
42 L</Selected Bug Fixes> section.
44 [ List each security issue as a =head2 entry ]
46 =head1 Incompatible Changes
48 XXX For a release on a stable branch, this section aspires to be:
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.
54 [ List each incompatible change as a =head2 entry ]
58 XXX Any deprecated features, syntax, modules etc. should be listed here.
60 =head2 Module removals
62 XXX Remove this section if inapplicable.
64 The following modules will be removed from the core distribution in a
65 future release, and will at that time need to be installed from CPAN.
66 Distributions on CPAN which require these modules will need to list them as
69 The core versions of these modules will now issue C<"deprecated">-category
70 warnings to alert you to this fact. To silence these deprecation warnings,
71 install the modules in question from CPAN.
73 Note that these are (with rare exceptions) fine modules that you are encouraged
74 to continue to use. Their disinclusion from core primarily hinges on their
75 necessity to bootstrapping a fully functional, CPAN-capable Perl installation,
76 not usually on concerns over their design.
80 XXX Note that deprecated modules should be listed here even if they are listed
81 as an updated module in the L</Modules and Pragmata> section.
85 [ List each other deprecation as a =head2 entry ]
87 =head1 Performance Enhancements
89 XXX Changes which enhance performance without changing behaviour go here.
90 There may well be none in a stable release.
92 [ List each enhancement as a =item entry ]
102 =head1 Modules and Pragmata
104 XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
105 go here. If Module::CoreList is updated, generate an initial draft of the
106 following sections using F<Porting/corelist-perldelta.pl>, which prints stub
107 entries to STDOUT. Results can be pasted in place of the '=head2' entries
108 below. A paragraph summary for important changes should then be added by hand.
109 In an ideal world, dual-life modules would have a F<Changes> file that could be
112 [ Within each section, list entries as a =item entry ]
114 =head2 New Modules and Pragmata
124 =head2 Updated Modules and Pragmata
130 L<B> has been upgraded from version 1.44 to 1.45.
132 Calling the C<GV> method on C<B::CV> objects created from a lexical
133 sub would return nonsense, possibly crashing perl. C<GV> now returns
134 C<undef> for lexical subs. [perl #118525]
136 Added the C<NAME_HEK> method to return the name of a lexical sub.
140 L<bignum> has been upgraded from version 0.35 to 0.36.
142 L<bigrat> wasn't correctly updating an internal variable when C<use>d
143 with a C<lib> option.
147 L<Config::Perl::V> has been upgraded from version 0.18 to 0.19.
151 L<Data::Dumper> has been upgraded from version 2.147 to 2.148.
153 The compatbility of the XS implementation with the pure perl version
154 under C<Useqq> has been improved. [perl #118933]
158 L<Devel::Peek> has been upgraded from version 1.12 to 1.13.
160 The C<SvREFCNT_inc()> and C<SvREFCNT_dec()> functions have been
161 removed and C<SvREFCNT()> will now work on non-scalars. [perl #117793]
165 L<Exporter> has been upgraded from version 5.68 to 5.69.
167 L<Exporter> would ignore custom C<$SIG{__WARN__}> handlers in
168 C<Exporter::Heavy>. [perl #39739]
172 L<IPC::Cmd> has been upgraded from version 0.82 to 0.84.
174 C<run_forked> has various fixes/improvements, L<Socket> is only used where
175 needed and a regression introduced in 0.78 has been fixed.
179 The libnet module collection has been upgraded from version 1.22 to 1.22_02.
183 L<List::Util> has been upgraded from version 1.27 to 1.30
185 L<List::Util> now includes C<pairgrep>, C<pairmap>, C<pairs>, C<pairkeys>,
186 C<pairvalues> and C<pairfirst> functions that operate on even-sized lists of
191 L<parent> has been upgraded from version 0.225 to 0.226.
195 L<Socket> has been upgraded from version 2.010 to 2.011.
197 Handle FreeBSD (or other platforms) returning shorter AF_UNIX sockaddr
198 structures due to embedded sun_len. [cpan #86613]
202 L<Storable> has been upgraded from version 2.45 to 2.46.
204 Avoid creating temporary objects for STORABLE_attach when they aren't
205 required. [perl #118907]
209 =head2 Removed Modules and Pragmata
221 XXX Changes to files in F<pod/> go here. Consider grouping entries by
222 file and be sure to link to the appropriate page, e.g. L<perlfunc>.
224 =head2 New Documentation
226 XXX Changes which create B<new> files in F<pod/> go here.
230 XXX Description of the purpose of the new file here
232 =head2 Changes to Existing Documentation
234 XXX Changes which significantly change existing files in F<pod/> go here.
235 However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
238 =head3 L<perlopentut>
244 The C<open> tutorial has been completely rewriten by Tom Christiansen, and now
245 focuses on covering only the basics, rather than providing a comprehensive
246 reference to all things openable. This rewrite came as the result of a
247 vigorous discussion on perl5-porters kicked off by a set of improvements
248 written by Alexander Hartmaier to the existing C<perlopentut>. A "more than
249 you ever wanted to know about C<open>" document may follow in subsequent
256 The following additions or changes have been made to diagnostic output,
257 including warnings and fatal error messages. For the complete list of
258 diagnostic messages, see L<perldiag>.
260 XXX New or changed warnings emitted by the core's C<C> code go here. Also
261 include any changes in L<perldiag> that reconcile it to the C<C> code.
263 =head2 New Diagnostics
265 XXX Newly added diagnostic messages go under here, separated into New Errors
274 XXX L<message|perldiag/"message">
284 XXX L<message|perldiag/"message">
288 =head2 Changes to Existing Diagnostics
290 XXX Changes (i.e. rewording) of diagnostic messages go here
296 XXX Describe change here
300 =head1 Utility Changes
302 XXX Changes to installed programs such as F<perlbug> and F<xsubpp> go here.
303 Most of these are built within the directories F<utils> and F<x2p>.
305 [ List utility changes as a =head3 entry for each utility and =item
306 entries for each change
307 Use L<XXX> with program names to get proper documentation linking. ]
319 =head1 Configuration and Compilation
321 XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
322 go here. Any other changes to the Perl build process should be listed here.
323 However, any platform-specific changes should be listed in the
324 L</Platform Support> section, instead.
326 [ List changes as a =item entry ].
338 XXX Any significant changes to the testing of a freshly built perl should be
339 listed here. Changes which create B<new> files in F<t/> go here as do any
340 large changes to the testing harness (e.g. when parallel testing was added).
341 Changes to existing files in F<t/> aren't worth summarizing, although the bugs
342 that they represent may be covered elsewhere.
344 [ List each test improvement as a =item entry ]
354 =head1 Platform Support
356 XXX Any changes to platform support should be listed in the sections below.
358 [ Within the sections, list each platform as a =item entry with specific
359 changes as paragraphs below it. ]
363 XXX List any platforms that this version of perl compiles on, that previous
364 versions did not. These will either be enabled by new files in the F<hints/>
365 directories, or new subdirectories and F<README> files at the top level of the
370 =item XXX-some-platform
376 =head2 Discontinued Platforms
378 XXX List any platforms that this version of perl no longer compiles on.
382 =item XXX-some-platform
388 =head2 Platform-Specific Notes
390 XXX List any changes for specific platforms. This could include configuration
391 and compilation changes or changes in portability/compatibility. However,
392 changes within modules for platforms should generally be listed in the
393 L</Modules and Pragmata> section.
397 =item XXX-some-platform
403 =head1 Internal Changes
405 XXX Changes which affect the interface available to C<XS> code go here. Other
406 significant internal changes for future core maintainers should be noted as
409 [ List each change as a =item entry ]
419 =head1 Selected Bug Fixes
421 XXX Important bug fixes in the core language are summarized here. Bug fixes in
422 files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
424 [ List each fix as a =item entry ]
430 Autovivifying a subroutine stub via C<\&$glob> started causing crashes in
431 Perl 5.18.0 if the $glob was merely a copy of a real glob, i.e., a scalar
432 that had had a glob assigned to it. This has been fixed [perl #119051].
436 =head1 Known Problems
438 XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
439 tests that had to be C<TODO>ed for the release would be noted here. Unfixed
440 platform specific bugs also go here.
442 [ List each fix as a =item entry ]
454 XXX If any significant core contributor has died, we've added a short obituary
457 =head1 Acknowledgements
459 XXX Generate this with:
461 perl Porting/acknowledgements.pl v5.19.2..HEAD
463 =head1 Reporting Bugs
465 If you find what you think is a bug, you might check the articles recently
466 posted to the comp.lang.perl.misc newsgroup and the perl bug database at
467 http://rt.perl.org/perlbug/ . There may also be information at
468 http://www.perl.org/ , the Perl Home Page.
470 If you believe you have an unreported bug, please run the L<perlbug> program
471 included with your release. Be sure to trim your bug down to a tiny but
472 sufficient test case. Your bug report, along with the output of C<perl -V>,
473 will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
475 If the bug you are reporting has security implications, which make it
476 inappropriate to send to a publicly archived mailing list, then please send it
477 to perl5-security-report@perl.org. This points to a closed subscription
478 unarchived mailing list, which includes all the core committers, who will be
479 able to help assess the impact of issues, figure out a resolution, and help
480 co-ordinate the release of patches to mitigate or fix the problem across all
481 platforms on which Perl is supported. Please only use this address for
482 security issues in the Perl core, not for modules independently distributed on
487 The F<Changes> file for an explanation of how to view exhaustive details on
490 The F<INSTALL> file for how to build Perl.
492 The F<README> file for general stuff.
494 The F<Artistic> and F<Copying> files for copyright information.