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 v5.21.3
12 This document describes differences between the 5.21.2 release and the 5.21.3
15 If you are upgrading from an earlier release such as 5.21.1, first read
16 L<perl5212delta>, which describes differences between 5.21.1 and 5.21.2.
20 XXX Any important notices here
22 =head1 Core Enhancements
24 =head2 C<defined(@array = LIST)> is no longer fatal
26 In 5.21.1, C<defined(@array)> was made fatal. This has been relaxed
27 to not die if the argument is assigning to an array.
31 =head2 The L<Safe> module could allow outside packages to be replaced
33 Critical bugfix: outside packages could be replaced. L<Safe> has
34 been patched to 2.38 to address this.
36 =head1 Incompatible Changes
38 =head2 S<C<use UNIVERSAL '...'>> is now a fatal error
40 Importing functions from C<UNIVERSAL> has been deprecated since v5.12, and
41 is now a fatal error. S<C<"use UNIVERSAL">> without any arguments is still
44 =head1 Modules and Pragmata
46 =head2 Updated Modules and Pragmata
52 L<B::Debug> has been upgraded from version 1.19 to 1.21
56 L<Config::Perl::V> has been upgraded from version 0.20 to 0.22.
60 L<CPAN::Meta> has been upgraded from version 2.141520 to 2.142060.
64 L<CPAN::Meta::Requirements> has been upgraded from version 2.125 to 2.126.
68 L<ExtUtils::Manifest> has been upgraded from version 1.64 to 1.65.
70 The MANIFEST is now opened with C<:raw>, to prevent C<CRLF>s leaking in.
74 L<HTTP::Tiny> has been upgraded from version 0.043 to 0.047.
78 L<perl5db.pl> has been upgraded from version 1.45 to 1.46.
80 Fixed the scope level handling of the debugger's C<y> command.
84 L<POSIX> has been upgraded from version 1.41 to 1.42.
86 Replaced the thread-unsafe code used to prevent duplicate warning
87 messages for using the isxxx() functions. [perl #122476]
91 L<Safe> has been upgraded from version 2.37 to 2.38.
93 Critical bugfix: outside packages could be replaced.
97 L<Socket> has been upgraded from version 2.014 to 2.015.
99 Test suite updates, particularly useful for Solaris and cygwin, and
100 a slight change to the pattern used for IPv4 address matching.
106 =head2 Changes to Existing Documentation
108 =head3 L<perlexperiment>
114 Added reference to L<feature>.
124 Details on C level symbols and libperl.t added.
128 =head3 L<perlhacktips>
134 Recommended replacements for tmpfile, atoi, strtol, and strtoul added.
144 ASCII v. EBCDIC clarifications added.
154 Comments added on algorithmic complexity and tied hashes.
164 Updated documentation on environment and shell interaction in VMS.
170 The following additions or changes have been made to diagnostic output,
171 including warnings and fatal error messages. For the complete list of
172 diagnostic messages, see L<perldiag>.
174 =head2 New Diagnostics
182 L<Hexadecimal float: internal error|perldiag/"Hexadecimal float: internal error">
184 (F) Something went horribly bad in hexadecimal float handling.
188 L<Hexadecimal float: unsupported long double format|perldiag/"Hexadecimal float: unsupported long double format">
190 (F) You have configured Perl to use long doubles but
191 the internals of the long double format are unknown,
192 therefore the hexadecimal float output is impossible.
202 L<Hexadecimal float: exponent overflow|perldiag/"Hexadecimal float: exponent overflow">
204 (W overflow) The hexadecimal floating point has larger exponent
205 than the floating point supports.
209 L<Hexadecimal float: exponent underflow|perldiag/"Hexadecimal float: exponent underflow">
211 (W overflow) The hexadecimal floating point has smaller exponent
212 than the floating point supports.
216 L<Hexadecimal float: mantissa overflow|perldiag/"Hexadecimal float: mantissa overflow">
218 (W overflow) The hexadecimal floating point literal had more bits in
219 the mantissa (the part between the 0x and the exponent, also known as
220 the fraction or the significand) than the floating point supports.
224 L<Hexadecimal float: precision loss|perldiag/"Hexadecimal float: precision loss">
226 (W overflow) The hexadecimal floating point had internally more
227 digits than could be output. This can be caused by unsupported
228 long double formats, or by 64-bit integers not being available
229 (needed to retrieve the digits under some configurations).
233 =head2 Changes to Existing Diagnostics
239 L<require> with no argument or undef used to warn about a Null filename; now
240 it dies with C<Missing or undefined argument to require>.
244 =head1 Configuration and Compilation
246 XXX Changes to F<Configure>, F<installperl>, F<installman>, and analogous tools
247 go here. Any other changes to the Perl build process should be listed here.
248 However, any platform-specific changes should be listed in the
249 L</Platform Support> section, instead.
251 [ List changes as a =item entry ].
257 Internal handling of floating point values has been improved.
263 XXX Any significant changes to the testing of a freshly built perl should be
264 listed here. Changes which create B<new> files in F<t/> go here as do any
265 large changes to the testing harness (e.g. when parallel testing was added).
266 Changes to existing files in F<t/> aren't worth summarizing, although the bugs
267 that they represent may be covered elsewhere.
269 [ List each test improvement as a =item entry ]
279 =head1 Platform Support
281 =head2 Platform-Specific Notes
287 Build support has been improved for cross-compiling in general and for
288 Android in particular.
292 C<c99> options have been cleaned up, hints look for C<solstudio>
293 as well as C<SUNWspro>, and support for native C<setenv> has been added.
297 C<finite>, C<finitel>, and C<isfinite> detection has been added to
298 C<configure.com>, environment handling has had some minor changes, and
299 a fix for legacy feature checking status.
303 C<%I64d> is now being used instead of C<%lld> for MinGW.
307 =head1 Internal Changes
309 XXX Changes which affect the interface available to C<XS> code go here. Other
310 significant internal changes for future core maintainers should be noted as
313 [ List each change as a =item entry ]
319 Added L<perlapi/sync_locale>.
320 Changing the program's locale should be avoided by XS code. Nevertheless,
321 certain non-Perl libraries called from XS, such as C<Gtk> do so. When this
322 happens, Perl needs to be told that the locale has changed. Use this function
323 to do so, before returning to Perl.
327 Added L<perlapi/grok_atou> as a safer replacement for atoi and strtol.
331 =head1 Selected Bug Fixes
333 XXX Important bug fixes in the core language are summarized here. Bug fixes in
334 files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
336 [ List each fix as a =item entry ]
342 Failing to compile C<use Foo> in an eval could leave a spurious
343 C<BEGIN> subroutine definition, which would produce a "Subroutine
344 BEGIN redefined" warning on the next use of C<use>, or other C<BEGIN>
345 block. [perl #122107]
349 C<method { BLOCK } ARGS> syntax now correctly parses the arguments if they
350 begin with an opening brace. [perl #46947]
354 External libraries and Perl may have different ideas of what the locale is.
355 This is problematic when parsing version strings if the locale's numeric
356 separator has been changed. Version parsing has been patched to ensure
357 it handles the locales correctly. [perl #121930]
361 A bug has been fixed where zero-length assertions and code blocks inside of a
362 regex could cause L<pos> to see an incorrect value. [perl #122460]
366 =head1 Known Problems
368 XXX Descriptions of platform agnostic bugs we know we can't fix go here. Any
369 tests that had to be C<TODO>ed for the release would be noted here. Unfixed
370 platform specific bugs also go here.
372 [ List each fix as a =item entry ]
382 =head1 Errata From Previous Releases
388 XXX Add anything here that we forgot to add, or were mistaken about, in
389 the perldelta of a previous release.
393 =head1 Acknowledgements
395 XXX Generate this with:
397 perl Porting/acknowledgements.pl v5.21.2..HEAD
399 =head1 Reporting Bugs
401 If you find what you think is a bug, you might check the articles recently
402 posted to the comp.lang.perl.misc newsgroup and the perl bug database at
403 https://rt.perl.org/ . There may also be information at
404 http://www.perl.org/ , the Perl Home Page.
406 If you believe you have an unreported bug, please run the L<perlbug> program
407 included with your release. Be sure to trim your bug down to a tiny but
408 sufficient test case. Your bug report, along with the output of C<perl -V>,
409 will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
411 If the bug you are reporting has security implications, which make it
412 inappropriate to send to a publicly archived mailing list, then please send it
413 to perl5-security-report@perl.org. This points to a closed subscription
414 unarchived mailing list, which includes all the core committers, who will be
415 able to help assess the impact of issues, figure out a resolution, and help
416 co-ordinate the release of patches to mitigate or fix the problem across all
417 platforms on which Perl is supported. Please only use this address for
418 security issues in the Perl core, not for modules independently distributed on
423 The F<Changes> file for an explanation of how to view exhaustive details on
426 The F<INSTALL> file for how to build Perl.
428 The F<README> file for general stuff.
430 The F<Artistic> and F<Copying> files for copyright information.