5 perl5197delta - what is new for perl v5.19.7
9 This document describes differences between the 5.19.6 release and the 5.19.7
12 If you are upgrading from an earlier release such as 5.19.5, first read
13 L<perl5196delta>, which describes differences between 5.19.5 and 5.19.6.
15 =head1 Core Enhancements
17 =head2 Postfix syntax for maximum array index
19 The postfix notation C<< ->$#* >> has been added, to match the similar
20 postfix operators added in 5.19.5. C<< $foo->$#* >> is equivalent to
21 C<$#$foo>. See L<perlref>.
23 =head1 Incompatible Changes
25 =head2 Data::Dumper's output may change
27 Depending on the data structures dumped and the settings set for
28 Data::Dumper, the dumped output may have changed from previous
31 If you have tests that depend on the exact output of Data::Dumper,
34 To avoid this problem in your code, test against the data structure
35 from evaluating the dumped structure, instead of the dump itself.
41 The C<< CGI.pm >> module has been deprecated since version 3.64.
43 =head1 Modules and Pragmata
45 =head2 Updated Modules and Pragmata
51 L<base> has been upgraded from version 2.19 to 2.20.
53 C<base> now only ignores load failure on the requested module. [perl
58 L<CGI> has been upgraded from version 3.63 to 3.64.
60 Avoids a warning about "undefined variable in user_agent" in some cases, and
61 updates L<CGI::Cookie> documentation to reflect that "HttpOnly" is widely
64 NOTE: L<CGI> is deprecated and may be removed from a future version of Perl.
68 L<constant> has been upgraded from version 1.29 to 1.30.
72 L<CPAN::Meta> has been upgraded from version 2.132830 to 2.133380.
76 L<Data::Dumper> has been upgraded from version 2.149 to 2.150.
78 Regular expression objects are now dumped in a form closer to their
79 original source, eg. C< qr/abc/i > is dumped as exactly that instead of
80 C< qr/(?^i:abc)/ >. [perl #82948]
82 Dumping of hash keys is now more consistent between the XS and perl
83 implementations of L<Data::Dumper>, including how the C<quotekeys>
84 option behaves. This may make tests that depend on the exact output
85 of Data::Dumper to fail. [perl #120384]
89 L<DynaLoader> has been upgraded from version 1.21 to 1.22.
93 L<ExtUtils::MakeMaker> has been upgraded from version 6.82 to 6.84.
97 L<File::Fetch> has been upgraded from version 0.44 to 0.46.
99 Blacklists "ftp" on DragonflyBSD.
103 L<HTTP::Tiny> has been upgraded from version 0.038 to 0.039.
107 L<inc::latest> has been upgraded from version 0.4202 to 0.4203.
108 NOTE: L<inc::latest> is deprecated and may be removed from a future version of Perl.
112 L<Locale::Codes> has been upgraded from version 3.27 to 3.28.
116 L<Module::Build> has been upgraded from version 0.4202 to 0.4203.
117 NOTE: L<Module::Build> is deprecated and may be removed from a future version of Perl.
121 L<Module::CoreList> has been upgraded from version 3.01 to 3.02.
125 L<PerlIO::encoding> has been upgraded from version 0.16 to 0.17.
129 L<PerlIO::via> has been upgraded from version 0.13 to 0.14.
133 L<POSIX> has been upgraded from version 1.36 to 1.37.
137 L<SDBM_File> has been upgraded from 1.10 to 1.11.
139 Added access to SDBM constants and to opening SDBM files with explicit
140 page and directory file names. [perl #114350]
144 L<Storable> has been upgraded from version 2.47 to 2.48.
148 L<threads> has been upgraded from version 1.90 to 1.91.
152 L<Time::Piece> has been upgraded from version 1.23 to 1.24.
156 L<Unicode::Collate> has been upgraded from version 1.02 to 1.04.
160 L<Win32> has been upgraded from version 0.47 to 0.48.
166 The following additions or changes have been made to diagnostic output,
167 including warnings and fatal error messages. For the complete list of
168 diagnostic messages, see L<perldiag>.
170 =head2 New Diagnostics
178 L<Useless use of greediness modifier|perldiag/"Useless use of greediness modifier '%c' in regex; marked by <-- HERE in m/%s/">
180 This fixes [Perl #42957].
184 =head2 Changes to Existing Diagnostics
190 The error messages for C<my($a?$b$c)> and C<my(do{})> now mention
191 "conditional expression" and "do block", respectively, instead of reading
192 'Can't declare null operation in "my"'.
196 =head1 Utility Changes
198 =head3 C<< Porting/corelist-perldelta.pl >>
204 Ensure that the latest version of Module::CoreList is used when
215 Various tests in F<t/porting/> are no longer skipped when the perl
216 F<.git> directory is outside the perl tree and pointed to by
217 C<$GIT_DIR>. [perl #120505]
221 =head1 Platform Support
223 =head2 Platform-Specific Notes
229 Experimental support for building with Intel C++ Compiler has been extended to
230 cover the dmake makefile (win32/makefile.mk) as well.
234 =head1 Internal Changes
240 The C<sv> argument in L<perlapi/sv_2pv_flags>, L<perlapi/sv_2iv_flags>,
241 L<perlapi/sv_2uv_flags>, and L<perlapi/sv_2nv_flags> and their older wrappers
242 sv_2pv, sv_2iv, sv_2uv, sv_2nv, is now non-NULL. Passing NULL now will crash.
243 When the non-NULL marker was introduced en masse in 5.9.3 the functions
244 were marked non-NULL, but since the creation of the SV API in 5.0 alpha 2, if
245 NULL was passed, the functions returned 0 or false-type values. The code that
246 supports C<sv> argument being non-NULL dates to 5.0 alpha 2 directly, and
247 indirectly to Perl 1.0 (pre 5.0 api). The lack of documentation that the
248 functions accepted a NULL C<sv> was corrected in 5.11.0 and between 5.11.0
249 and 5.19.5 the functions were marked NULLOK. As an optimization the NULLOK code
250 has now been removed, and the functions became non-NULL marked again, because
251 core getter-type macros never pass NULL to these functions and would crash
252 before ever passing NULL.
254 The only way a NULL C<sv> can be passed to sv_2*v* functions is if XS code
255 directly calls sv_2*v*. This is unlikely as XS code uses Sv*V* macros to get
256 the underlying value out of the SV. One possible situation which leads to
257 a NULL C<sv> being passed to sv_2*v* functions, is if XS code defines its own
258 getter type Sv*V* macros, which check for NULL B<before> dereferencing and
259 checking the SV's flags through public API Sv*OK* macros or directly using
260 private API C<SvFLAGS>, and if C<sv> is NULL, then calling the sv_2*v functions
261 with a NULL litteral or passing the C<sv> containing a NULL value.
265 =head1 Selected Bug Fixes
271 C<< semctl(..., SETVAL, ...) >> would set the semaphore to the top
272 32-bits of the supplied integer instead of the bottom 32-bits on
273 64-bit big-endian systems. [perl #120635]
277 A regression since v5.18.0 has been fixed in which C<qr/[[:^ascii:]]/d>
278 failed to match any character in the range C<\x80> - C<\xFF> if its
279 surrounding character class contained anything else. (That is, the bug
280 didn't happen if the C<[:^ascii:]> was the only element of the character
281 class.) [perl #120799]
285 C<< readdir() >> now only sets C<$!> on error. C<$!> is no longer set
286 to C<EBADF> when then terminating C<undef> is read from the directory
287 unless the system call sets C<$!>. [perl #118651]
291 C<&CORE::glob> no longer causes an intermittent crash due to perl's stack
292 getting corrupted. [perl #119993]
296 C<open> with layers that load modules (e.g., "<:encoding(utf8)") no longer
297 runs the risk of crashing due to stack corruption.
301 When a reference to a reference to an overloaded object was returned from
302 a regular expression C<(??{...})> code block, an incorrect implicit
303 dereference could take place if the inner reference had been returned by
304 a code block previously.
308 A tied variable returned from C<(??{...})> sees the inner values of match
309 variables (i.e., the $1 etc. from any matches inside the block) in its
310 FETCH method. This was not the case if a reference to an overloaded object
311 was the last thing assigned to the tied variable. Instead, the match
312 variables referred to the outer pattern during the FETCH call.
316 Perl 5.18 broke autoloading via C<< ->SUPER::foo >> method calls by looking
317 up AUTOLOAD from the current package rather than the current package's
318 superclass. This has been fixed. [perl #120694]
322 A longstanding bug causing C<do {} until CONSTANT>, where the constant
323 holds a true value, to read unallocated memory has been resolved. This
324 would usually happen after a syntax error. In past versions of Perl it has
325 crashed intermittently. [perl #72406]
329 Fix HP-UX $! failure. HP-UX strerror() returns an empty string for an
330 unknown error code. This caused an assertion to fail under DEBUGGING
331 builds. This patch removes the assertion and changes the return into
332 a non-empty string indicating the errno is for an unknown error.
336 Fix unexpected tainting via regexp using locale. Previously, under certain
337 conditions, the use of character classes could cause tainting when it
338 shouldn't. Some character classes are locale-dependent, but before this
339 patch, sometimes tainting was happening even for character classes that
340 don't depend on the locale. [perl #120675]
344 Under certain conditions, Perl would throw an error if in an lookbehind
345 assertion in a regexp, the assertion referred to a named subpattern,
346 complaining the lookbehind was variable when it wasn't. This has been
347 fixed. [perl #120600], [perl #120618]. The current fix may be improved
352 =head1 Acknowledgements
354 Perl 5.19.7 represents approximately 4 weeks of development since Perl 5.19.6
355 and contains approximately 90,000 lines of changes across 390 files from 26
358 Perl continues to flourish into its third decade thanks to a vibrant community
359 of users and developers. The following people are known to have contributed the
360 improvements that became Perl 5.19.7:
362 Abigail, Abir Viqar, Brian Childs, Brian Fraser, Chris 'BinGOs' Williams, Craig
363 A. Berry, Dabrien 'Dabe' Murphy, Daniel Dragan, David Mitchell, Dennis
364 Kaarsemaker, Evan Zacks, Father Chrysostomos, François Perrad, Graham Knop,
365 James E Keenan, Jess Robinson, Karl Williamson, Kevin Ryde, Martin McGrath,
366 Matthew Horsfall, Nicholas Clark, Peter Martini, Ricardo Signes, Steve Hay,
367 Tony Cook, Yves Orton.
369 The list above is almost certainly incomplete as it is automatically generated
370 from version control history. In particular, it does not include the names of
371 the (very much appreciated) contributors who reported issues to the Perl bug
374 Many of the changes included in this version originated in the CPAN modules
375 included in Perl's core. We're grateful to the entire CPAN community for
376 helping Perl to flourish.
378 For a more complete list of all of Perl's historical contributors, please see
379 the F<AUTHORS> file in the Perl source distribution.
381 =head1 Reporting Bugs
383 If you find what you think is a bug, you might check the articles recently
384 posted to the comp.lang.perl.misc newsgroup and the perl bug database at
385 https://rt.perl.org/ . There may also be information at
386 http://www.perl.org/ , the Perl Home Page.
388 If you believe you have an unreported bug, please run the L<perlbug> program
389 included with your release. Be sure to trim your bug down to a tiny but
390 sufficient test case. Your bug report, along with the output of C<perl -V>,
391 will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
393 If the bug you are reporting has security implications, which make it
394 inappropriate to send to a publicly archived mailing list, then please send it
395 to perl5-security-report@perl.org. This points to a closed subscription
396 unarchived mailing list, which includes all the core committers, who will be
397 able to help assess the impact of issues, figure out a resolution, and help
398 co-ordinate the release of patches to mitigate or fix the problem across all
399 platforms on which Perl is supported. Please only use this address for
400 security issues in the Perl core, not for modules independently distributed on
405 The F<Changes> file for an explanation of how to view exhaustive details on
408 The F<INSTALL> file for how to build Perl.
410 The F<README> file for general stuff.
412 The F<Artistic> and F<Copying> files for copyright information.