5 perl5110delta - what is new for perl v5.11.0
9 This document describes differences between the 5.10.0 release and
10 the 5.11.0 development release.
12 =head1 Incompatible Changes
14 =head2 Unicode interpretation of \w, \d, \s, and the POSIX character classes redefined.
16 Previous versions of Perl tried to map POSIX style character class definitions onto
17 Unicode property names so that patterns would "dwim" when matches were made against latin-1 or
18 unicode strings. This proved to be a mistake, breaking character class negation, causing
19 forward compatibility problems (as Unicode keeps updating their property definitions and adding
20 new characters), and other problems.
22 Therefore we have now defined a new set of artificial "unicode" property names which will be
23 used to do unicode matching of patterns using POSIX style character classes and perl short-form
24 escape character classes like \w and \d.
26 The key change here is that \d will no longer match every digit in the unicode standard
27 (there are thousands) nor will \w match every word character in the standard, instead they
28 will match precisely their POSIX or Perl definition.
30 Those needing to match based on Unicode properties can continue to do so by using the \p{} syntax
31 to match whichever property they like, including the new artificial definitions.
33 B<NOTE:> This is a backwards incompatible no-warning change in behaviour. If you are upgrading
34 and you process large volumes of text look for POSIX and Perl style character classes and
35 change them to the relevent property name (by removing the word 'Posix' from the current name).
37 The following table maps the POSIX character class names, the escapes and the old and new
38 Unicode property mappings:
40 POSIX Esc Class New-Property ! Old-Property
41 ----------------------------------------------+-------------
42 alnum [0-9A-Za-z] IsPosixAlnum ! IsAlnum
43 alpha [A-Za-z] IsPosixAlpha ! IsAlpha
44 ascii [\000-\177] IsASCII = IsASCII
45 blank [\011 ] IsPosixBlank !
46 cntrl [\0-\37\177] IsPosixCntrl ! IsCntrl
47 digit \d [0-9] IsPosixDigit ! IsDigit
48 graph [!-~] IsPosixGraph ! IsGraph
49 lower [a-z] IsPosixLower ! IsLower
50 print [ -~] IsPosixPrint ! IsPrint
51 punct [!-/:-@[-`{-~] IsPosixPunct ! IsPunct
52 space [\11-\15 ] IsPosixSpace ! IsSpace
53 \s [\11\12\14\15 ] IsPerlSpace ! IsSpacePerl
54 upper [A-Z] IsPosixUpper ! IsUpper
55 word \w [0-9A-Z_a-z] IsPerlWord ! IsWord
56 xdigit [0-9A-Fa-f] IsXDigit = IsXDigit
58 If you wish to build perl with the old mapping you may do so by setting
60 #define PERL_LEGACY_UNICODE_CHARCLASS_MAPPINGS 1
62 in regcomp.h, and then setting
64 PERL_TEST_LEGACY_POSIX_CC
66 to true your enviornment when testing.
69 =head2 In @INC, move ARCHLIB and PRIVLIB after the current version's site_perl and vendor_perl.
71 =head2 Switch statement changes
73 The handling of complex expressions by the C<given>/C<when> switch
74 statement has been enhanced. These enhancements are also available in
75 5.10.1 and subsequent 5.10 releases. There are two new cases where C<when> now
76 interprets its argument as a boolean, instead of an expression to be used
81 =item flip-flop operators
83 The C<..> and C<...> flip-flop operators are now evaluated in boolean
84 context, following their usual semantics; see L<perlop/"Range Operators">.
86 Note that, as in perl 5.10.0, C<when (1..10)> will not work to test
87 whether a given value is an integer between 1 and 10; you should use
88 C<when ([1..10])> instead (note the array reference).
90 However, contrary to 5.10.0, evaluating the flip-flop operators in boolean
91 context ensures it can now be useful in a C<when()>, notably for
92 implementing bistable conditions, like in:
94 when (/^=begin/ .. /^=end/) {
98 =item defined-or operator
100 A compound expression involving the defined-or operator, as in
101 C<when (expr1 // expr2)>, will be treated as boolean if the first
102 expression is boolean. (This just extends the existing rule that applies
103 to the regular or operator, as in C<when (expr1 || expr2)>.)
107 The next section details more changes brought to the semantics to
108 the smart match operator, that naturally also modify the behaviour
109 of the switch statements where smart matching is implicitly used.
110 These changers were also made for the 5.10.1 release, and will remain in
111 subsequent 5.10 releases.
113 =head2 Smart match changes
115 =head3 Changes to type-based dispatch
117 The smart match operator C<~~> is no longer commutative. The behaviour of
118 a smart match now depends primarily on the type of its right hand
119 argument. Moreover, its semantics have been adjusted for greater
120 consistency or usefulness in several cases. While the general backwards
121 compatibility is maintained, several changes must be noted:
127 Code references with an empty prototype are no longer treated specially.
128 They are passed an argument like the other code references (even if they
129 choose to ignore it).
133 C<%hash ~~ sub {}> and C<@array ~~ sub {}> now test that the subroutine
134 returns a true value for each key of the hash (or element of the
135 array), instead of passing the whole hash or array as a reference to
140 Due to the commutativity breakage, code references are no longer
141 treated specially when appearing on the left of the C<~~> operator,
142 but like any vulgar scalar.
146 C<undef ~~ %hash> is always false (since C<undef> can't be a key in a
147 hash). No implicit conversion to C<""> is done (as was the case in perl
152 C<$scalar ~~ @array> now always distributes the smart match across the
153 elements of the array. It's true if one element in @array verifies
154 C<$scalar ~~ $element>. This is a generalization of the old behaviour
155 that tested whether the array contained the scalar.
159 The full dispatch table for the smart match operator is given in
160 L<perlsyn/"Smart matching in detail">.
162 =head3 Smart match and overloading
164 According to the rule of dispatch based on the rightmost argument type,
165 when an object overloading C<~~> appears on the right side of the
166 operator, the overload routine will always be called (with a 3rd argument
167 set to a true value, see L<overload>.) However, when the object will
168 appear on the left, the overload routine will be called only when the
169 rightmost argument is a simple scalar. This way distributivity of smart match
170 across arrays is not broken, as well as the other behaviours with complex
171 types (coderefs, hashes, regexes). Thus, writers of overloading routines
172 for smart match mostly need to worry only with comparing against a scalar,
173 and possibly with stringification overloading; the other common cases
174 will be automatically handled consistently.
176 C<~~> will now refuse to work on objects that do not overload it (in order
177 to avoid relying on the object's underlying structure). (However, if the
178 object overloads the stringification or the numification operators, and
179 if overload fallback is active, it will be used instead, as usual.)
181 =head2 Labels can't be keywords
183 Labels used as targets for the C<goto>, C<last>, C<next> or C<redo>
184 statements cannot be keywords anymore. This restriction will prevent
185 potential confusion between the C<goto LABEL> and C<goto EXPR> syntaxes:
186 for example, a statement like C<goto print> would jump to a label whose
187 name would be the return value of C<print()>, (usually 1), instead of a
188 label named C<print>. Moreover, the other control flow statements
189 would just ignore any keyword passed to them as a label name. Since
190 such labels cannot be defined anymore, this kind of error will be
193 =head2 Other incompatible changes
199 The semantics of C<use feature :5.10*> have changed slightly.
200 See L<"Modules and Pragmata"> for more information.
204 It is now a run-time error to use the smart match operator C<~~>
205 with an object that has no overload defined for it. (This way
206 C<~~> will not break encapsulation by matching against the
207 object's internal representation as a reference.)
211 The version control system used for the development of the perl
212 interpreter has been switched from Perforce to git. This is mainly an
213 internal issue that only affects people actively working on the perl core;
214 but it may have minor external visibility, for example in some of details
215 of the output of C<perl -V>. See L<perlrepository> for more information.
219 The internal structure of the C<ext/> directory in the perl source has
220 been reorganised. In general, a module C<Foo::Bar> whose source was
221 stored under F<ext/Foo/Bar/> is now located under F<ext/Foo-Bar/>. Also,
222 nearly all dual-life modules have been moved from F<lib/> to F<ext/>. This
223 is purely a source tarball change, and should make no difference to the
224 compilation or installation of perl, unless you have a very customised build
225 process that explicitly relies on this structure, or which hard-codes the
226 C<nonxs_ext> F<Configure> parameter. Specifically, this change does not by
227 default alter the location of any files in the final installation.
231 As part of the C<Test::Harness> 2.x to 3.x upgrade, the experimental
232 C<Test::Harness::Straps> module has been removed.
233 See L</"Updated Modules"> for more details.
237 As part of the C<ExtUtils::MakeMaker> upgrade, the
238 C<ExtUtils::MakeMaker::bytes> and C<ExtUtils::MakeMaker::vmsish> modules
239 have been removed from this distribution.
243 C<Module::CoreList> no longer contains the C<%:patchlevel> hash.
247 This one is actually a change introduced in 5.10.0, but it was missed
248 from that release's perldelta, so it is mentioned here instead.
250 A bugfix related to the handling of the C</m> modifier and C<qr> resulted
251 in a change of behaviour between 5.8.x and 5.10.0:
253 # matches in 5.8.x, doesn't match in 5.10.0
254 $re = qr/^bar/; "foo\nbar" =~ /$re/m;
258 C<length undef> now returns undef.
262 =head1 Core Enhancements
264 =head2 Unicode Character Database 5.1.0
266 The copy of the Unicode Character Database included in Perl 5.11.0 has
267 been updated to 5.1.0 from 5.0.0. See
268 L<http://www.unicode.org/versions/Unicode5.1.0/#Notable_Changes> for the
271 =head2 A proper interface for pluggable Method Resolution Orders
273 As of Perl 5.11.0 there is a new interface for plugging and using method
274 resolution orders other than the default (linear depth first search).
275 The C3 method resolution order added in 5.10.0 has been re-implemented as
276 a plugin, without changing its Perl-space interface. See L<perlmroapi> for
279 =head2 The C<overloading> pragma
281 This pragma allows you to lexically disable or enable overloading
282 for some or all operations. (Yuval Kogman)
284 =head2 C<\N> regex escape
286 A new regex escape has been added, C<\N>. It will match any character that
287 is not a newline, independently from the presence or absence of the single
288 line match modifier C</s>. (If C<\N> is followed by an opening brace and
289 by a letter, perl will still assume that a Unicode character name is
290 coming, so compatibility is preserved.) (Rafael Garcia-Suarez)
292 =head2 Implicit strictures
294 Using the C<use VERSION> syntax with a version number greater or equal
295 to 5.11.0 will also lexically enable strictures just like C<use strict>
296 would do (in addition to enabling features.) So, the following:
305 =head2 Parallel tests
307 The core distribution can now run its regression tests in parallel on
308 Unix-like platforms. Instead of running C<make test>, set C<TEST_JOBS> in
309 your environment to the number of tests to run in parallel, and run
310 C<make test_harness>. On a Bourne-like shell, this can be done as
312 TEST_JOBS=3 make test_harness # Run 3 tests in parallel
314 An environment variable is used, rather than parallel make itself, because
315 L<TAP::Harness> needs to be able to schedule individual non-conflicting test
316 scripts itself, and there is no standard interface to C<make> utilities to
317 interact with their job schedulers.
319 Note that currently some test scripts may fail when run in parallel (most
320 notably C<ext/IO/t/io_dir.t>). If necessary run just the failing scripts
321 again sequentially and see if the failures go away.
323 =head2 The C<...> operator
325 A new operator, C<...>, nicknamed the Yada Yada operator, has been added.
326 It is intended to mark placeholder code, that is not yet implemented.
327 See L<perlop/"Yada Yada Operator">. (chromatic)
329 =head2 DTrace support
331 Some support for DTrace has been added. See "DTrace support" in F<INSTALL>.
333 =head2 Support for C<configure_requires> in CPAN module metadata
335 Both C<CPAN> and C<CPANPLUS> now support the C<configure_requires> keyword
336 in the F<META.yml> metadata file included in most recent CPAN distributions.
337 This allows distribution authors to specify configuration prerequisites that
338 must be installed before running F<Makefile.PL> or F<Build.PL>.
340 See the documentation for C<ExtUtils::MakeMaker> or C<Module::Build> for more
341 on how to specify C<configure_requires> when creating a distribution for CPAN.
343 =head2 The C<each> function can now operate on arrays
345 =head2 Perl's core time-related functions are now Y2038 compliand
347 =head2 The variable C<$,> may now be tied
349 =head2 // now behaves like || in when clauses
351 =head2 You can now set C<-W> from the C<PERL5OPT> environment varialbe
353 =head1 Modules and Pragmata
355 =head2 New Modules and Pragmata
361 This is a new lexically-scoped alternative for the C<Fatal> module.
362 The bundled version is 2.06_01. Note that in this release, using a string
363 eval when C<autodie> is in effect can cause the autodie behaviour to leak
364 into the surrounding scope. See L<autodie/"BUGS"> for more details.
366 =item C<Compress::Raw::Bzip2>
368 This has been added to the core (version 2.020).
372 This pragma establishes an ISA relationship with base classes at compile
373 time. It provides the key feature of C<base> without the feature creep.
375 =item C<Parse::CPAN::Meta>
377 This has been added to the core (version 1.39).
381 =head2 Pragmata Changes
387 See L</"The C<overloading> pragma"> above.
391 Upgraded from version 0.08 to 0.09.
395 The C<attrs> pragma has been removed. It had been marked as deprecated since
400 Upgraded from version 2.13 to 2.14. See L<parent> for a replacement.
404 Upgraded from version 0.22 to 0.23.
408 Upgraded from version 0.22 to 0.23.
412 Upgraded from version 0.22 to 0.23.
416 Upgraded from version 1.06 to 1.07.
418 The Unicode F<NameAliases.txt> database file has been added. This has the
419 effect of adding some extra C<\N> character names that formerly wouldn't
420 have been recognised; for example, C<"\N{LATIN CAPITAL LETTER GHA}">.
424 Upgraded from version 1.13 to 1.19. Some code has been shifted from run time to
425 compile time, and the amount of MRO cache flushing has been minimised.
429 The meaning of the C<:5.10> and C<:5.10.X> feature bundles has
430 changed slightly. The last component, if any (i.e. C<X>) is simply ignored.
431 This is predicated on the assumption that new features will not, in
432 general, be added to maintenance releases. So C<:5.10> and C<:5.10.X>
433 have identical effect. This is a change to the behaviour documented for
438 Upgraded from version 2.13 to 2.14 (this was just a version bump; there
439 were no functional changes).
443 Upgraded from version 0.5565 to 0.62.
447 Upgraded from version 1.06 to 1.07.
451 Upgraded from version 1.06 to 1.07.
455 See L</"The C<overloading> pragma"> above.
459 Upgraded from version 1.00 to 1.01. Performance for single inheritance is 40%
460 faster - see L</"Performance Enhancements"> below.
462 C<mro> is now implemented as an XS extension. The documented interface has not
463 changed. Code relying on the implementation detail that some C<mro::>
464 methods happened to be available at all times gets to "keep both pieces".
468 Upgraded from version 0.74 to 0.77.
472 =head2 Updated Modules
476 =item C<Archive::Extract>
478 Upgraded from version 0.24 to 0.34.
480 =item C<Archive::Tar>
482 Upgraded from version 1.38 to 1.52.
484 =item C<Attribute::Handlers>
486 Upgraded from version 0.79 to 0.85.
490 Upgraded from version 5.63 to 5.68.
494 Upgraded from version 1.05 to 1.06.
498 Upgraded from version 1.17 to 1.22.
502 Upgraded from version 1.05 to 1.11.
506 Upgraded from version 0.83 to 0.89.
510 Upgraded from version 1.09 to 1.11.
514 Upgraded from version 1.01 to 1.02.
518 Upgraded from version 1.10 to 1.11.
522 Upgraded from version 1.08 to 1.11.
524 L<Carp> now includes all the necessary code to function. Previously, it
525 used to be a lightweight placeholder that loaded the actual code from
526 C<Carp::Heavy> on demand. C<Carp::Heavy> is now a simple, empty module
527 kept for backwards compatibility for programs that used to pre-load it.
531 Upgraded from version 3.29 to 3.43.
532 (also includes the "default_value for popup_menu()" fix from 3.45).
534 =item C<Compress::Zlib>
536 Upgraded from version 2.008 to 2.020.
540 Upgraded from version 1.9205 to 1.9402. C<CPAN::FTP> has a local fix to
541 stop it being too verbose on download failure.
545 Upgraded from version 0.84 to 0.88.
547 =item C<CPANPLUS::Dist::Build>
549 Upgraded from version 0.06_02 to 0.36.
553 Upgraded from version 3.25_01 to 3.30.
555 =item C<Data::Dumper>
557 Upgraded from version 2.121_14 to 2.124.
561 Upgraded from version 1.01 to 1.02.
565 Upgraded from version 1.816_1 to 1.820.
567 =item C<Devel::PPPort>
569 Upgraded from version 3.13 to 3.19.
573 Upgraded from version 2.36_01 to 2.39.
577 Upgraded from version 5.45 to 5.47.
581 Upgraded from version 1.01 to 1.03.
585 Upgraded from version 1.12 to 1.13.
589 Upgraded from version 1.08 to 1.10.
593 Upgraded from version 2.23 to 2.35.
597 Upgraded from version 1.10 to 1.11.
601 Upgraded from version 5.62 to 5.63.
603 =item C<ExtUtils::CBuilder>
605 Upgraded from version 0.21 to 0.2602.
607 =item C<ExtUtils::Command>
609 Upgraded from version 1.13 to 1.16.
611 =item C<ExtUtils::Constant>
613 Upgraded from 0.20 to 0.22. (Note that neither of these versions are
616 =item C<ExtUtils::Embed>
618 Upgraded from version 1.27 to 1.28.
620 =item C<ExtUtils::Install>
622 Upgraded from version 1.44 to 1.54.
624 =item C<ExtUtils::MakeMaker>
626 Upgraded from version 6.42 to 6.55_02.
628 Note that C<ExtUtils::MakeMaker::bytes> and C<ExtUtils::MakeMaker::vmsish>
629 have been removed from this distribution.
631 =item C<ExtUtils::Manifest>
633 Upgraded from version 1.51_01 to 1.56.
635 =item C<ExtUtils::ParseXS>
637 Upgraded from version 2.18_02 to 2.2002.
641 Upgraded from version 1.05 to 2.06_01. See also the new pragma C<autodie>.
643 =item C<File::Basename>
645 Upgraded from version 2.76 to 2.77.
647 =item C<File::Compare>
649 Upgraded from version 1.1005 to 1.1006.
653 Upgraded from version 2.11 to 2.16.
655 File::Copy now always return 0 (not "") on failure.
657 FIXME - describe C<cp>
661 Upgraded from version 0.14 to 0.20.
665 Upgraded from version 1.12 to 1.14.
669 Upgraded from version 2.04 to 2.07_03.
673 Upgraded from version 3.2501 to 3.30.
677 Upgraded from version 1.00 to 1.01.
679 Added -X overloading, -M, -C and -A.
683 Upgraded from version 0.18 to 0.22.
687 Upgraded from version 1.07 to 1.08.
691 Upgraded from version 2.01 to 2.02.
693 =item C<Filter::Simple>
695 Upgraded from version 0.82 to 0.84.
697 =item C<Filter::Util::Call>
699 Upgraded from version 1.07 to 1.08.
703 Upgraded from version 1.49 to 1.50.
707 Upgraded from version 1.08 to 1.09.
709 =item C<Getopt::Long>
711 Upgraded from version 2.37 to 2.38.
713 =item C<Hash::Util::FieldHash>
715 Upgraded from version 1.03 to 1.04. This fixes a memory leak.
717 =item C<I18N::Collate>
719 Upgraded from version 1.00 to 1.01.
723 Upgraded from version 1.23_01 to 1.25.
725 This makes non-blocking mode work on Windows in C<IO::Socket::INET>
728 =item C<IO::Compress::*>
730 Upgraded from version 2.008 to 2.020.
734 Upgraded from version 1.06 to 1.07.
738 Upgraded from version 1.27 to 1.28.
742 Upgraded from version 1.30_01 to 1.31.
746 Upgraded from version 1.07 to 1.09.
750 Upgraded from version 0.40_1 to 0.46.
754 Upgraded from version 1.02 to 1.04.
758 Upgraded from version 1.05 to 2.01.
762 Upgraded from version 0.5565 to 0.62.
766 Upgraded from version 1.19 to 1.21.
768 =item C<Locale::MakeText>
770 Upgraded from version 1.12 to 1.13.
772 =item C<Log::Message>
774 Upgraded from version 0.01 to 0.02.
776 =item C<Math::BigFloat>
778 Upgraded from version 1.59 to 1.60.
780 =item C<Math::BigInt>
782 Upgraded from version 1.88 to 1.89.
784 =item C<Math::BigInt::FastCalc>
786 Upgraded from version 0.16 to 0.19.
788 =item C<Math::BigRat>
790 Upgraded from version 0.21 to 0.22.
792 =item C<Math::Complex>
794 Upgraded from version 1.37 to 1.56.
798 Upgraded from version 1.04 to 1.20.
802 Upgraded from version 1.01_02 to 1.01_03 (just a minor documentation
805 =item C<Module::Build>
807 Upgraded from version 0.2808_01 to 0.34_02.
809 =item C<Module::CoreList>
811 Upgraded from version 2.13 to 2.18. This release no longer contains the
812 C<%Module::CoreList::patchlevel> hash.
814 =item C<Module::Load>
816 Upgraded from version 0.12 to 0.16.
818 =item C<Module::Load::Conditional>
820 Upgraded from version 0.22 to 0.30.
822 =item C<Module::Loaded>
824 Upgraded from version 0.01 to 0.02.
826 =item C<Module::Pluggable>
828 Upgraded from version 3.6 to 3.9.
832 Upgraded from version 1.07 to 1.08.
836 Upgraded from version 2.33 to 2.36.
840 Upgraded from version 0.60_01 to 0.64.
842 =item C<Object::Accessor>
844 Upgraded from version 0.32 to 0.34.
848 Upgraded from version 1.03 to 1.04.
850 =item C<Package::Constants>
852 Upgraded from version 0.01 to 0.02.
856 Upgraded from version 1.04 to 1.06.
860 Upgraded from version 0.04 to 0.07.
864 Upgraded from version 2.16 to 2.22.
868 Upgraded from version 1.35 to 1.37.
872 Upgrade from version 3.14_02 to 3.15.
876 Upgraded from version 3.05 to 3.07.
880 Upgraded from version 3.08 to 3.13.
884 Upgraded from version 1.13 to 1.17.
888 Upgraded from 2.12 to 2.18.
890 =item C<Scalar::Util>
892 Upgraded from version 1.19 to 1.21.
896 Upgraded from 1.01 to 1.02.
900 Upgraded from 1.11 to 1.17.
904 Upgraded from 1.80 to 1.84.
906 As of 1.84, C<Socket> can now handle abstract namespace sockets on Linux.
911 Upgraded from 2.18 to 2.20.
915 Upgraded from version 2.13 to 2.14. Please see L</Deprecations>.
919 Upgraded from version 1.06 to 1.07.
923 Upgraded from version 0.22 to 0.27.
925 =item C<Term::ANSIColor>
927 Upgraded from version 1.12 to 2.01.
929 =item C<Term::ReadLine>
931 Upgraded from version 1.03 to 1.04.
935 Upgraded from version 0.18 to 0.20.
937 =item C<Test::Harness>
939 Upgraded from version 2.64 to 3.17.
941 Note that one side-effect of the 2.x to 3.x upgrade is that the
942 experimental C<Test::Harness::Straps> module (and its supporting
943 C<Assert>, C<Iterator>, C<Point> and C<Results> modules) have been
944 removed. If you still need this, then they are available in the
945 (unmaintained) C<Test-Harness-Straps> distribution on CPAN.
947 =item C<Test::Simple>
949 Upgraded from version 0.72 to 0.92.
951 =item C<Text::ParseWords>
953 Upgraded from version 3.26 to 3.27.
957 Upgraded from version 2007.1117 to 2009.0305.
961 Upgraded from version 2006.1117 to 2009.0305.
963 =item C<Thread::Queue>
965 Upgraded from version 2.00 to 2.11.
967 =item C<Thread::Semaphore>
969 Upgraded from version 2.01 to 2.09.
973 Upgraded from version 1.67 to 1.73.
975 =item C<threads::shared>
977 Upgraded from version 1.14 to 1.29.
979 =item C<Tie::RefHash>
981 Upgraded from version 1.37 to 1.38.
983 =item C<Tie::StdHandle>
985 This has documentation changes, and has been assigned a version for the
986 first time: version 4.2.
990 Upgraded from version 1.9711 to 1.9719.
994 Upgraded from version 1.18 to 1.1901.
998 Upgraded from version 1.12 to 1.15.
1000 =item C<Unicode::Normalize>
1002 Upgraded from version 1.02 to 1.03.
1004 =item C<Unicode::UCD>
1006 Upgraded from version 0.25 to 0.27.
1008 C<charinfo()> now works on Unified CJK code points added to later versions
1011 C<casefold()> has new fields returned to provide both a simpler interface
1012 and previously missing information. The old fields are retained for
1013 backwards compatibility. Information about Turkic-specific code points is
1016 The documentation has been corrected and expanded.
1020 Upgraded from version 1.04 to 1.05.
1022 C<< UNIVERSAL->import() >> is now deprecated.
1026 Upgraded from version 0.34 to 0.39.
1028 =item C<Win32API::File>
1030 Upgraded from version 0.1001_01 to 0.1101.
1034 Upgraded from version 0.08 to 0.10.
1038 =head1 Utility Changes
1044 Now looks in C<include-fixed> too, which is a recent addition to gcc's
1049 No longer incorrectly treats enum values like macros (Daniel Burr).
1051 Now handles C++ style constants (C<//>) properly in enums. (A patch from
1052 Rainer Weikusat was used; Daniel Burr also proposed a similar fix).
1056 C<LVALUE> subroutines now work under the debugger.
1058 The debugger now correctly handles proxy constant subroutines, and
1063 F<perlbug> now uses C<%Module::CoreList::bug_tracker> to print out upstream bug
1066 Where the user names a module that their bug report is about, and we know the
1067 URL for its upstream bug tracker, provide a message to the user explaining
1068 that the core copies the CPAN version directly, and provide the URL for
1069 reporting the bug directly to upstream.
1073 Perl 5.11.0 added a new utility F<perlthanks>, which is a variant of
1074 F<perlbug>, but for sending non-bug-reports to the authors and maintainers
1075 of Perl. Getting nothing but bug reports can become a bit demoralising:
1076 we'll see if this changes things.
1080 =head1 New Documentation
1086 This contains instructions on how to build perl for the Haiku platform.
1090 This describes the new interface for pluggable Method Resolution Orders.
1094 This document, by Richard Foley, provides an introduction to the use of
1095 performance and optimization techniques which can be used with particular
1096 reference to perl programs.
1098 =item L<perlrepository>
1100 This describes how to access the perl source using the I<git> version
1105 This describes the new F<perlthanks> utility.
1109 =head1 Changes to Existing Documentation
1111 The various large F<Changes*> files (which listed every change made to perl
1112 over the last 18 years) have been removed, and replaced by a small file,
1113 also called F<Changes>, which just explains how that same information may
1114 be extracted from the git version control system.
1116 The file F<Porting/patching.pod> has been deleted, as it mainly described
1117 interacting with the old Perforce-based repository, which is now obsolete.
1118 Information still relevant has been moved to L<perlrepository>.
1120 L<perlapi>, L<perlintern>, L<perlmodlib> and L<perltoc> are now all
1121 generated at build time, rather than being shipped as part of the release.
1123 =head2 Documented -X overloading.
1125 =head2 Documented that C<when()> treats specially most of the filetest operators
1127 =head2 Documented when as a syntax modifier
1129 =head2 Eliminated "Old Perl threads tutorial", which describes 5005 threads.
1131 pod/perlthrtut.pod is the same material reworked for ithreads.
1133 =head2 Correct previous documentation: v-strings are not deprecated
1135 With version objects, we need them to use MODULE VERSION syntax. This
1136 patch removes the deprecation note.
1138 =head1 Performance Enhancements
1144 A new internal cache means that C<isa()> will often be faster.
1148 The implementation of C<C3> Method Resolution Order has been optimised -
1149 linearisation for classes with single inheritance is 40% faster. Performance
1150 for multiple inheritance is unchanged.
1154 Under C<use locale>, the locale-relevant information is now cached on
1155 read-only values, such as the list returned by C<keys %hash>. This makes
1156 operations such as C<sort keys %hash> in the scope of C<use locale> much
1161 Empty C<DESTROY> methods are no longer called.
1165 Faster C<Perl_sv_utf8_upgrade()>
1169 Speed up C<keys> on empty hash
1173 =head1 Installation and Configuration Improvements
1175 =head2 F<ext/> reorganisation
1177 The layout of directories in F<ext> has been revised. Specifically, all
1178 extensions are now flat, and at the top level, with C</> in pathnames
1179 replaced by C<->, so that F<ext/Data/Dumper/> is now F<ext/Data-Dumper/>,
1180 etc. The names of the extensions as specified to F<Configure>, and as
1181 reported by C<%Config::Config> under the keys C<dynamic_ext>,
1182 C<known_extensions>, C<nonxs_ext> and C<static_ext> have not changed, and
1183 still use C</>. Hence this change will not have any affect once perl is
1184 installed. C<Safe> has been split out from being part of C<Opcode>, and
1185 C<mro> is now an extension in its own right.
1187 Nearly all dual-life modules have been moved from F<lib> to F<ext>, and will
1188 now appear as known C<nonxs_ext>. This will made no difference to the
1189 structure of an installed perl, nor will the modules installed differ,
1190 unless you run F<Configure> with options to specify an exact list of
1191 extensions to build. In this case, you will rapidly become aware that you
1192 need to add to your list, because various modules needed to complete the
1193 build, such as C<ExtUtils::ParseXS>, have now become extensions, and
1194 without them the build will fail well before it attempts to run the
1197 =head2 Configuration improvements
1199 If C<vendorlib> and C<vendorarch> are the same, then they are only added to
1202 C<$Config{usedevel}> and the C-level C<PERL_USE_DEVEL> are now defined if
1203 perl is built with C<-Dusedevel>.
1205 F<Configure> will enable use of C<-fstack-protector>, to provide protection
1206 against stack-smashing attacks, if the compiler supports it.
1208 F<Configure> will now determine the correct prototypes for re-entrant
1209 functions, and for C<gconvert>, if you are using a C++ compiler rather
1212 On Unix, if you build from a tree containing a git repository, the
1213 configuration process will note the commit hash you have checked out, for
1214 display in the output of C<perl -v> and C<perl -V>. Unpushed local commits
1215 are automatically added to the list of local patches displayed by
1218 =head2 Compilation improvements
1220 As part of the flattening of F<ext>, all extensions on all platforms are
1221 built by F<make_ext.pl>. This replaces the Unix-specific
1222 F<ext/util/make_ext>, VMS-specific F<make_ext.com> and Win32-specific
1223 F<win32/buildext.pl>.
1225 =head2 Platform Specific Changes
1231 Removed F<libbsd> for AIX 5L and 6.1. Only C<flock()> was used from F<libbsd>.
1233 Removed F<libgdbm> for AIX 5L and 6.1. The F<libgdbm> is delivered as an
1234 optional package with the AIX Toolbox. Unfortunately the 64 bit version
1237 Hints changes mean that AIX 4.2 should work again.
1241 On Cygwin we now strip the last number from the DLL. This has been the
1242 behaviour in the cygwin.com build for years. The hints files have been
1247 Support for Apollo DomainOS was removed in Perl 5.11.0
1251 The hints files now identify the correct threading libraries on FreeBSD 7
1256 We now work around a bizarre preprocessor bug in the Irix 6.5 compiler:
1257 C<cc -E -> unfortunately goes into K&R mode, but C<cc -E file.c> doesn't.
1261 Patches from the Haiku maintainers have been merged in. Perl should now
1266 Support for Atari MiNT was removed in Perl 5.11.0.
1270 Perl should now build on MirOS BSD.
1274 Hints now supports versions 5.*.
1278 Various changes from Stratus have been merged in.
1282 There is now support for Symbian S60 3.2 SDK and S60 5.0 SDK.
1286 Improved message window handling means that C<alarm> and C<kill> messages
1287 will no longer be dropped under race conditions.
1291 Reads from the in-memory temporary files of C<PerlIO::scalar> used to fail
1292 if C<$/> was set to a numeric reference (to indicate record-style reads).
1295 VMS now supports C<getgrgid>.
1297 Many improvements and cleanups have been made to the VMS file name handling
1298 and conversion code.
1300 Enabling the C<PERL_VMS_POSIX_EXIT> logical name now encodes a POSIX exit
1301 status in a VMS condition value for better interaction with GNV's bash
1302 shell and other utilities that depend on POSIX exit values. See
1303 L<perlvms/"$?"> for details.
1305 C<File::Copy> now detects Unix compatibility mode on VMS.
1309 =head1 Selected Bug Fixes
1315 C<-I> on shebang line now adds directories in front of @INC.
1316 as documented, and as does C<-I> when specified on the command-line.
1321 C<kill> is now fatal when called on non-numeric process identifiers.
1322 Previously, an 'undef' process identifier would be interpreted as a request to
1323 kill process "0", which would terminate the current process group on POSIX
1324 systems. Since process identifiers are always integers, killing a non-numeric
1325 process is now fatal.
1329 5.10.0 inadvertently disabled an optimisation, which caused a measurable
1330 performance drop in list assignment, such as is often used to assign
1331 function parameters from C<@_>. The optimisation has been re-instated, and
1332 the performance regression fixed.
1336 Fixed memory leak on C<while (1) { map 1, 1 }> [RT #53038].
1340 Some potential coredumps in PerlIO fixed [RT #57322,54828].
1344 The debugger now works with lvalue subroutines.
1348 The debugger's C<m> command was broken on modules that defined constants
1353 C<crypt> and string complement could return tainted values for untainted
1354 arguments [RT #59998].
1358 The C<-i>I<.suffix> command-line switch now recreates the file using
1359 restricted permissions, before changing its mode to match the original
1360 file. This eliminates a potential race condition [RT #60904].
1364 On some UNIX systems, the value in C<$?> would not have the top bit set
1365 (C<$? & 128>) even if the child core dumped.
1369 Under some circumstances, C<$^R> could incorrectly become undefined
1374 In the XS API, various hash functions, when passed a pre-computed hash where
1375 the key is UTF-8, might result in an incorrect lookup.
1379 XS code including F<XSUB.h> before F<perl.h> gave a compile-time error
1384 C<< $object->isa('Foo') >> would report false if the package C<Foo> didn't
1385 exist, even if the object's C<@ISA> contained C<Foo>.
1389 Various bugs in the new-to 5.10.0 mro code, triggered by manipulating
1390 C<@ISA>, have been found and fixed.
1394 Bitwise operations on references could crash the interpreter, e.g.
1395 C<$x=\$y; $x |= "foo"> [RT #54956].
1399 Patterns including alternation might be sensitive to the internal UTF-8
1400 representation, e.g.
1402 my $byte = chr(192);
1403 my $utf8 = chr(192); utf8::upgrade($utf8);
1404 $utf8 =~ /$byte|X}/i; # failed in 5.10.0
1408 Within UTF8-encoded Perl source files (i.e. where C<use utf8> is in
1409 effect), double-quoted literal strings could be corrupted where a C<\xNN>,
1410 C<\0NNN> or C<\N{}> is followed by a literal character with ordinal value
1411 greater than 255 [RT #59908].
1415 C<B::Deparse> failed to correctly deparse various constructs:
1416 C<readpipe STRING> [RT #62428], C<CORE::require(STRING)> [RT #62488],
1417 C<sub foo(_)> [RT #62484].
1421 Using C<setpgrp> with no arguments could corrupt the perl stack.
1425 The block form of C<eval> is now specifically trappable by C<Safe> and
1426 C<ops>. Previously it was erroneously treated like string C<eval>.
1430 In 5.10.0, the two characters C<[~> were sometimes parsed as the smart
1431 match operator (C<~~>) [RT #63854].
1435 In 5.10.0, the C<*> quantifier in patterns was sometimes treated as
1436 C<{0,32767}> [RT #60034, #60464]. For example, this match would fail:
1438 ("ab" x 32768) =~ /^(ab)*$/
1442 C<shmget> was limited to a 32 bit segment size on a 64 bit OS [RT #63924].
1446 Using C<next> or C<last> to exit a C<given> block no longer produces a
1447 spurious warning like the following:
1449 Exiting given via last at foo.pl line 123
1453 On Windows, C<'.\foo'> and C<'..\foo'> were treated differently than
1454 C<'./foo'> and C<'../foo'> by C<do> and C<require> [RT #63492].
1458 Assigning a format to a glob could corrupt the format; e.g.:
1460 *bar=*foo{FORMAT}; # foo format now bad
1464 Attempting to coerce a typeglob to a string or number could cause an
1465 assertion failure. The correct error message is now generated,
1466 C<Can't coerce GLOB to I<$type>>.
1470 Under C<use filetest 'access'>, C<-x> was using the wrong access mode. This
1471 has been fixed [RT #49003].
1475 C<length> on a tied scalar that returned a Unicode value would not be
1476 correct the first time. This has been fixed.
1480 Using an array C<tie> inside in array C<tie> could SEGV. This has been
1485 A race condition inside C<PerlIOStdio_close()> has been identified and
1486 fixed. This used to cause various threading issues, including SEGVs.
1490 In C<unpack>, the use of C<()> groups in scalar context was internally
1491 placing a list on the interpreter's stack, which manifested in various
1492 ways, including SEGVs. This is now fixed [RT #50256].
1496 Magic was called twice in C<substr>, C<\&$x>, C<tie $x, $m> and C<chop>.
1497 These have all been fixed.
1501 A 5.10.0 optimisation to clear the temporary stack within the implicit
1502 loop of C<s///ge> has been reverted, as it turned out to be the cause of
1503 obscure bugs in seemingly unrelated parts of the interpreter [commit
1508 The line numbers for warnings inside C<elsif> are now correct.
1512 The C<..> operator now works correctly with ranges whose ends are at or
1513 close to the values of the smallest and largest integers.
1517 C<binmode STDIN, ':raw'> could lead to segmentation faults on some platforms.
1518 This has been fixed [RT #54828].
1522 An off-by-one error meant that C<index $str, ...> was effectively being
1523 executed as C<index "$str\0", ...>. This has been fixed [RT #53746].
1527 Various leaks associated with named captures in regexes have been fixed
1532 A weak reference to a hash would leak. This was affecting C<DBI>
1537 Using (?|) in a regex could cause a segfault [RT #59734].
1541 Use of a UTF-8 C<tr//> within a closure could cause a segfault [RT #61520].
1545 Calling C<Perl_sv_chop()> or otherwise upgrading an SV could result in an
1546 unaligned 64-bit access on the SPARC architecture [RT #60574].
1550 In the 5.10.0 release, C<inc_version_list> would incorrectly list
1551 C<5.10.*> after C<5.8.*>; this affected the C<@INC> search order
1556 In 5.10.0, C<pack "a*", $tainted_value> returned a non-tainted value
1561 In 5.10.0, C<printf> and C<sprintf> could produce the fatal error
1562 C<panic: utf8_mg_pos_cache_update> when printing UTF-8 strings
1567 In the 5.10.0 release, a dynamically created C<AUTOLOAD> method might be
1568 missed (method cache issue) [RT #60220,60232].
1572 In the 5.10.0 release, a combination of C<use feature> and C<//ee> could
1573 cause a memory leak [RT #63110].
1577 C<-C> on the shebang (C<#!>) line is once more permitted if it is also
1578 specified on the command line. C<-C> on the shebang line used to be a
1579 silent no-op I<if> it was not also on the command line, so perl 5.10.0
1580 disallowed it, which broke some scripts. Now perl checks whether it is
1581 also on the command line and only dies if it is not [RT #67880].
1585 In 5.10.0, certain types of re-entrant regular expression could crash,
1586 or cause the following assertion failure [RT #60508]:
1588 Assertion rx->sublen >= (s - rx->subbeg) + i failed
1592 =head1 New or Changed Diagnostics
1596 =item C<panic: sv_chop %s>
1598 This new fatal error occurs when the C routine C<Perl_sv_chop()> was
1599 passed a position that is not within the scalar's string buffer. This
1600 could be caused by buggy XS code, and at this point recovery is not
1603 =item C<Can't locate package %s for the parents of %s>
1605 This warning has been removed. In general, it only got produced in
1606 conjunction with other warnings, and removing it allowed an ISA lookup
1607 optimisation to be added.
1609 =item C<v-string in use/require is non-portable>
1611 This warning has been removed.
1613 =item C<Deep recursion on subroutine "%s">
1615 It is now possible to change the depth threshold for this warning from the
1616 default of 100, by recompiling the F<perl> binary, setting the C
1617 pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value.
1621 =head1 Changed Internals
1627 The J.R.R. Tolkien quotes at the head of C source file have been checked and
1628 proper citations added, thanks to a patch from Tom Christiansen.
1632 C<Perl_vcroak()> now accepts a null first argument. In addition, a full audit
1633 was made of the "not NULL" compiler annotations, and those for several
1634 other internal functions were corrected.
1638 New macros C<dSAVEDERRNO>, C<dSAVE_ERRNO>, C<SAVE_ERRNO>, C<RESTORE_ERRNO>
1639 have been added to formalise the temporary saving of the C<errno>
1644 The function C<Perl_sv_insert_flags> has been added to augment
1649 The function C<Perl_newSV_type(type)> has been added, equivalent to
1650 C<Perl_newSV()> followed by C<Perl_sv_upgrade(type)>.
1654 The function C<Perl_newSVpvn_flags()> has been added, equivalent to
1655 C<Perl_newSVpvn()> and then performing the action relevant to the flag.
1657 Two flag bits are currently supported.
1663 This will call C<SvUTF8_on()> for you. (Note that this does not convert an
1664 sequence of ISO 8859-1 characters to UTF-8). A wrapper, C<newSVpvn_utf8()>
1665 is available for this.
1669 Call C<Perl_sv_2mortal()> on the new SV.
1673 There is also a wrapper that takes constant strings, C<newSVpvs_flags()>.
1677 The function C<Perl_croak_xs_usage> has been added as a wrapper to
1682 The functions C<PerlIO_find_layer> and C<PerlIO_list_alloc> are now
1687 C<PL_na> has been exterminated from the core code, replaced by local STRLEN
1688 temporaries, or C<*_nolen()> calls. Either approach is faster than C<PL_na>,
1689 which is a pointer deference into the interpreter structure under ithreads,
1690 and a global variable otherwise.
1694 C<Perl_mg_free()> used to leave freed memory accessible via C<SvMAGIC()> on
1695 the scalar. It now updates the linked list to remove each piece of magic
1700 Under ithreads, the regex in C<PL_reg_curpm> is now reference counted. This
1701 eliminates a lot of hackish workarounds to cope with it not being reference
1706 C<Perl_mg_magical()> would sometimes incorrectly turn on C<SvRMAGICAL()>.
1707 This has been fixed.
1711 The I<public> IV and NV flags are now not set if the string value has
1712 trailing "garbage". This behaviour is consistent with not setting the
1713 public IV or NV flags if the value is out of range for the type.
1717 SV allocation tracing has been added to the diagnostics enabled by C<-Dm>.
1718 The tracing can alternatively output via the C<PERL_MEM_LOG> mechanism, if
1719 that was enabled when the F<perl> binary was compiled.
1723 Uses of C<Nullav>, C<Nullcv>, C<Nullhv>, C<Nullop>, C<Nullsv> etc have been
1724 replaced by C<NULL> in the core code, and non-dual-life modules, as C<NULL>
1725 is clearer to those unfamiliar with the core code.
1729 A macro C<MUTABLE_PTR(p)> has been added, which on (non-pedantic) gcc will
1730 not cast away C<const>, returning a C<void *>. Macros C<MUTABLE_SV(av)>,
1731 C<MUTABLE_SV(cv)> etc build on this, casting to C<AV *> etc without
1732 casting away C<const>. This allows proper compile-time auditing of
1733 C<const> correctness in the core, and helped picked up some errors (now
1738 Macros C<mPUSHs()> and C<mXPUSHs()> have been added, for pushing SVs on the
1739 stack and mortalizing them.
1743 Use of the private structure C<mro_meta> has changed slightly. Nothing
1744 outside the core should be accessing this directly anyway.
1748 A new tool, F<Porting/expand-macro.pl> has been added, that allows you
1749 to view how a C preprocessor macro would be expanded when compiled.
1750 This is handy when trying to decode the macro hell that is the perl
1757 Many modules updated from CPAN incorporate new tests.
1759 Several tests that have the potential to hang forever if they fail now
1760 incorporate a "watchdog" functionality that will kill them after a timeout,
1761 which helps ensure that C<make test> and C<make test_harness> run to
1762 completion automatically. (Jerry Hedden).
1764 Some core-specific tests have been added:
1768 =item t/comp/retainedlines.t
1770 Check that the debugger can retain source lines from C<eval>.
1772 =item t/io/perlio_fail.t
1774 Check that bad layers fail.
1776 =item t/io/perlio_leaks.t
1778 Check that PerlIO layers are not leaking.
1780 =item t/io/perlio_open.t
1782 Check that certain special forms of open work.
1786 General PerlIO tests.
1790 Check that there is no unexpected interaction between the internal types
1791 C<PVBM> and C<PVGV>.
1793 =item t/mro/package_aliases.t
1795 Check that mro works properly in the presence of aliased packages.
1799 Tests for C<dbmopen> and C<dbmclose>.
1801 =item t/op/index_thr.t
1803 Tests for the interaction of C<index> and threads.
1805 =item t/op/pat_thr.t
1807 Tests for the interaction of esoteric patterns and threads.
1811 Test that C<qr> doesn't leak.
1813 =item t/op/reg_email_thr.t
1815 Tests for the interaction of regex recursion and threads.
1817 =item t/op/regexp_qr_embed_thr.t
1819 Tests for the interaction of patterns with embedded C<qr//> and threads.
1821 =item t/op/regexp_unicode_prop.t
1823 Tests for Unicode properties in regular expressions.
1825 =item t/op/regexp_unicode_prop_thr.t
1827 Tests for the interaction of Unicode properties and threads.
1829 =item t/op/reg_nc_tie.t
1831 Test the tied methods of C<Tie::Hash::NamedCapture>.
1833 =item t/op/reg_posixcc.t
1835 Check that POSIX character classes behave consistently.
1839 Check that exportable C<re> functions in F<universal.c> work.
1841 =item t/op/setpgrpstack.t
1843 Check that C<setpgrp> works.
1845 =item t/op/substr_thr.t
1847 Tests for the interaction of C<substr> and threads.
1849 =item t/op/upgrade.t
1851 Check that upgrading and assigning scalars works.
1853 =item t/uni/lex_utf8.t
1855 Check that Unicode in the lexer works.
1859 Check that Unicode and C<tie> work.
1863 =head1 Known Problems
1865 This is a list of some significant unfixed bugs, which are regressions
1866 from either 5.10.0 or 5.8.x.
1872 C<List::Util::first> misbehaves in the presence of a lexical C<$_>
1873 (typically introduced by C<my $_> or implicitly by C<given>). The variable
1874 which gets set for each iteration is the package variable C<$_>, not the
1875 lexical C<$_> [RT #67694].
1877 A similar issue may occur in other modules that provide functions which
1878 take a block as their first argument, like
1880 foo { ... $_ ...} list
1884 The C<charnames> pragma may generate a run-time error when a regex is
1885 interpolated [RT #56444]:
1887 use charnames ':full';
1888 my $r1 = qr/\N{THAI CHARACTER SARA I}/;
1889 "foo" =~ $r1; # okay
1890 "foo" =~ /$r1+/; # runtime error
1892 A workaround is to generate the character outside of the regex:
1894 my $a = "\N{THAI CHARACTER SARA I}";
1899 Some regexes may run much more slowly when run in a child thread compared
1900 with the thread the pattern was compiled into [RT #55600].
1906 The following items are now deprecated.
1912 C<Switch> is buggy and should be avoided. From perl 5.11.0 onwards, it is
1913 intended that any use of the core version of this module will emit a
1914 warning, and that the module will eventually be removed from the core
1915 (probably in perl 5.14.0). See L<perlsyn/"Switch statements"> for its
1920 C<suidperl> has been removed. It used to provide a mechanism to
1921 emulate setuid permission bits on systems that don't support it properly.
1925 Deprecate assignment to $[
1929 Remove attrs, which has been deprecated since 1999/10/02.
1933 Deprecate use of the attribute :locked on subroutines.
1937 Deprecate using "locked" with the attributes pragma.
1941 Deprecate using "unique" with the attributes pragma.
1945 warn if ++ or -- are unable to change the value because it's beyond the limit of representation
1947 This uses a new warnings category: "imprecision".
1951 Make lc/uc/lcfirst/ucfirst warn when passed undef.
1955 Show constant in "Useless use of a constant in void context"
1959 Make the new warning report undef constants as undef
1963 Add a new warning, "Prototype after '%s'"
1967 Tweak the "Illegal character in prototype" warning so it's more precise when reporting illegal characters after _
1971 Unintented interpolation of $\ in regex
1975 Make overflow warnings in gmtime/localtime only occur when warnings are on
1979 Improve mro merging error messages.
1981 They are now very similar to those produced by Algorithm::C3.
1985 Amelioration of the error message "Unrecognized character %s in column %d"
1987 Changes the error message to "Unrecognized character %s; marked by <--
1988 HERE after %s<-- HERE near column %d". This should make it a little
1989 simpler to spot and correct the suspicious character.
1993 Explicitely point to $. when it causes an uninitialized warning for ranges in scalar context
1997 =head1 Acknowledgements
1999 Some of the work in this release was funded by a TPF grant funded by
2000 Dijkmat BV, The Netherlands.
2002 Steffen Mueller and David Golden in particular helped getting CPAN modules
2003 polished and synchronised with their in-core equivalents.
2005 Craig Berry was tireless in getting maint to run under VMS, no matter how
2006 many times we broke it for him.
2008 The other core committers contributed most of the changes, and applied most
2009 of the patches sent in by the hundreds of contributors listed in F<AUTHORS>.
2011 Much of the work of categorizing changes in this perldelta file was contributed
2012 by the following porters using changelogger.bestpractical.com:
2014 Nicholas Clark, leon, shawn, alexm, rjbs, rafl, Pedro Melo, brunorc,
2015 anonymous, ☄, Tom Hukins, anonymous, Jesse, dagolden, Moritz Onken,
2016 Mark Fowler, chorny, anonymous, tmtm
2018 Finally, thanks to Larry Wall, without whom none of this would be
2021 =head1 Reporting Bugs
2023 If you find what you think is a bug, you might check the articles
2024 recently posted to the comp.lang.perl.misc newsgroup and the perl
2025 bug database at http://rt.perl.org/perlbug/ . There may also be
2026 information at http://www.perl.org/ , the Perl Home Page.
2028 If you believe you have an unreported bug, please run the B<perlbug>
2029 program included with your release. Be sure to trim your bug down
2030 to a tiny but sufficient test case. Your bug report, along with the
2031 output of C<perl -V>, will be sent off to perlbug@perl.org to be
2032 analysed by the Perl porting team.
2034 If the bug you are reporting has security implications, which make it
2035 inappropriate to send to a publicly archived mailing list, then please send
2036 it to perl5-security-report@perl.org. This points to a closed subscription
2037 unarchived mailing list, which includes all the core committers, who be able
2038 to help assess the impact of issues, figure out a resolution, and help
2039 co-ordinate the release of patches to mitigate or fix the problem across all
2040 platforms on which Perl is supported. Please only use this address for
2041 security issues in the Perl core, not for modules independently
2042 distributed on CPAN.
2046 The F<Changes> file for an explanation of how to view exhaustive details
2049 The F<INSTALL> file for how to build Perl.
2051 The F<README> file for general stuff.
2053 The F<Artistic> and F<Copying> files for copyright information.
2060 The following changes are a filtered list of changes which weren't backported
2061 to 5.10.1. They were run through changelogger.bestpractical.com and triaged
2062 by a set of Perl 5 Porters. Changes to blead after 5945e41e have not yet
2063 been triaged or integrated.
2065 The following changes need to be
2067 1) deleted if they don't merit inclusion
2071 2) lightly copyedited and integrated into the perldelta above. Unfortunately, many of our
2072 commit messages are somewhat terse and require a bit more help to turn into something readable
2079 =head2 Move the reg_stringify logic to Perl_sv_2pv_flags
2081 =head2 mg_copy ought to take an I32
2083 =head2 Perl_store_cop_label() isn't meant to be part of the public API.
2085 =head2 Perl_gv_fetchmethod{,_autoload,_flags} are actually never* called with a non-NULL stash.
2086 So change the parameter to NN.
2089 =head2 Promote Perl_setdefout() to the public API.
2091 =head2 Add get_cvs() as a shortcut for STR_WITH_LEN() and Perl_get_cvn_flags()
2093 =head2 In Perl_newCONSTSUB(), sv should not be NULL.
2095 =head2 GvUNIQUE* have been defined as 0 since 2005/06/30 - high time to remove them.
2097 =head2 invert and rename PERL_MEM_LOG_STDERR to PERL_MEM_LOG_NOIMPL
2099 Most users who want PERL_MEM_LOG want the default implementation,
2100 give it to them. Users providing their own implementation can
2101 obtain current behavior by adding -DPERL_MEM_LOG_NOIMPL.
2102 Frankly, the average user probably wants _ENV by default too.
2104 =head2 simplify PERL_MEM_LOG
2106 This combines multiple environment variable reads into 1,
2107 where it looks for values like "2mst"
2108 -2 leading digits are atoi()d to get FD
2109 -m memory logging please
2111 -t timestamp those please.
2113 Combining these reduces overhead such that it seemed
2114 worthwhile to drop all the ifdefs. TBD whether this works
2115 in the environment that drove the original tradeoffs.
2117 If it isnt enough, Id be tempted by a global static ptr,
2118 and on 1st use, is read, seen 0, a lock is taken, and getenvar
2119 run to populate it, unlocked, proceed. This would remove
2120 iterative overheads.
2122 =head2 Add a parameter "destructing" to Gv_AMupdate()
2124 This boolean parameter indicates if the function has been called
2125 to update the overload magic table while looking up the DESTROY
2126 method. In this case, it's probably best to avoid croaking if
2127 those tables could not be updated (for example due to a method
2128 that could not be loaded.)
2130 =head2 Modify the return value of Gv_AMupdate to indicate a compilation error
2132 This way we'll restore most of the performance on object destruction
2133 lost by the previous commit
2136 =head2 local $SIG{FOO} = sub {...}; sets signal handler to SIG_DFL
2138 Re: [perl #60360] [PATCH] UPDATED: local $SIG{FOO} = sub {...}; sets signal handler to SIG_DFL
2139 Message-ID: <20081112234504.GI2062@tytlal.topaz.cx>
2141 Updated patch to retain source compatibility.
2143 Plus using the correct PERL_ARGS_ASSERT_SAVE_HELEM_FLAGS
2144 macro and running make regen.
2146 =head2 Respecting inc_version_list while processing PERL_VENDORLIB_STEM
2148 Respecting inc_version_list while processing PERL_VENDORLIB_STEM
2149 From: "Mandalemula, Rajesh" <Rajesh.Mandalemula@deshaw.com>
2151 =head2 Change PL_debug behaviour
2154 String eval lines are now saved whenever
2155 a subroutine is defined, even if the eval'd string has subsequent
2156 syntax errors. This allows the debugger to single step into these
2160 =head2 Tied filehandles now have an additional method EOF which provides the EOF type
2162 =head2 Perl is now smarter about adding a -I dir to the beginning or end of @INC
2164 =head2 On scope end, delete localized array elements that should not exist anymore, so that the array recovers its previous length. Honour EXISTS and DELETE for tied arrays.
2166 =head2 When a glob is deleted, mark its sub as ANON.
2168 =head2 Require a space or a newline after a "#line XXX" directive
2170 =head2 Forbid using "foreach" as an attribute
2172 (like all other control flow statements)
2175 =head2 Unregister signal handlers before destroying my_perl
2177 If the signal handler runs after perl_destruct() has been called, it
2178 will get an invalid (or NULL) my_perl when it asks for the
2179 thread-specific interpreter struct. This patch resets the signal
2180 handler for any signal previously handled by PL_csighandlerp to SIG_DFL
2181 before calling perl_destruct().
2183 =head2 Perl_magic_clearsig() needs to remove magic, else delete $SIG{INT} returns undef
2185 Perl_magic_clearsig() needs to remove magic, else delete $SIG{INT} returns undef
2186 instead of the now-removed INT handler.
2188 =head2 [perl #66452] TMPDIR not honored when opening an anonymous temporary file
2190 [perl #66452] TMPDIR not honored when opening an anonymous temporary file
2192 =head2 The attached patch to perlio.c fixes the problem of errno getting set.
2194 While I am firmly in the school of "do not look at $! except immediately
2195 after a failure", I also agree that spuriously setting it is messy. But
2196 there is just no way of knowing where your errno might have been.
2198 The problem was that PerlIO_fast_gets() (and other nearby similar
2199 capability-checking PerlIO routines) set the errno (and it was being
2200 called a lot, from sv_gets()). I think setting the errno here was
2201 a mistake: checking for "can has FOO" should not set external state,
2202 such as the errno. The patch removes that errno trashing from all those
2205 =head2 Trim all trailing / from "." in @INC when filling %INC
2207 This fixes bug #66942 : as a / was left in the directory name,
2208 $INC{"Foo.pm"} for a file loaded from the current directory
2209 was given the incorrect value "/Foo.pm".
2211 =head2 Don't enqueue pending signals during global destruction
2213 Global destruction is not signal-safe. PL_psig_pend may already
2214 be gone when the signal handler is called (with destruct_level > 0).
2215 NULL it before freeing it to prevent a race condition.
2217 =head2 Eliminate struct regexp_allocated and xpvio_allocated.
2219 Calculate memory allocation using regexp and XPVIO, and the offset of the first
2220 real structure member. This avoids tripping over alignment differences between
2221 X* and x*_allocated, because x*_allocated doesn't have a double in it.
2226 =head2 [perl #47047] Use of inherited AUTOLOAD for non-method is deprecated
2228 =head2 Remove the definitions of Null(), Nullch, Nullfp, Nullsv and PL_na when code is within the perl source tree
2230 =head2 Replace our assert-which-can-be-caught-by-eval with the real deal from the standard C library.
2232 =head2 Tweak Perl_sv_upgrade() so that references can upgrade to SVt_PV
2234 =head2 Eliminate prelen from struct regexp.
2236 =head2 Change Perl_av_iter_p() to return IV* rather than I32* (which means
2238 =head2 Reorder the external regexp flags to get RXf_PMf_STD_PMMOD into the
2240 lowest 4 bits (which saves a shift), and the "flags indicating special
2241 patterns" into contiguous bits. This makes everything a little tidier,
2242 and saves 88 bytes (woohoo!) of object file with -Os on x86 FreeBSD.
2245 =head2 Re-implement the SvOOK() hack to store the offset as a BER encoded number in the part of the PVX that is being released.
2247 fit, as chopping off 1 byte gives just enough space for recording a
2248 delta of up to 127). This allows SvOOK() to co-exist with SvIOK_on(),
2249 which means all the calls to SvOOK_off() [with the possibility of a
2250 call to sv_backoff()] in SvIOK_on() can be removed. This ought to make
2251 a lot of straight line code a little bit simpler.
2252 OOK()d scalars can now be SVt_PV, as the IVX isn't needed.
2254 =head2 Abolish wraplen from struct regexp. We're already storing it in SvCUR.
2256 =head2 Make Perl_pregcomp() use SvUTF8() of the pattern, rather than the flag bit in pmflags, to decide whether the pattern is UTF-8.
2258 =head2 Abolish RXf_UTF8. Store the UTF-8-ness of the pattern with SvUTF8().
2260 =head2 In struct regexp move the member paren_names to the IV union.
2262 =head2 Make REGEXP a type distinct from SV. (Much like AV, CV, GV, HV).
2264 =head2 Allow sv_setsv_flags() to copy SVt_REGEXP much like it copies SVt_FORMAT - the just string buffer.
2267 =head2 Correct a long-standing ithreads reference counting anonmaly
2269 The reference count only needs "doubling" when the scalar is pushed onto
2270 PL_regex_padav for the second time.
2273 =head2 In PL_regexp_padav, store regexps via real references, rather than hiding them within IVs.
2275 We can do this now that they are real SV pointers.
2277 =head2 With regexps stored as real RVs, we can eliminate SvREPADTMP().
2279 =head2 REGEXPs are now stored directly in PL_regex_padav, rather than indirectly via RVs.
2281 =head2 Remove code that protected pp_qr against REGEXPs going away during global destruction whilst they were stored via true references in PL_regex_padav.
2283 =head2 Remove PM_GETRE_SAFE and PM_SETRE_SAFE as nothing uses them.
2285 =head2 Note the U8 sized space created by removing -P, and check that it is now an illegal command line flag.
2287 =head2 Pack the recycled pad offsets into an SV at PL_regex_pad[0].
2289 =head2 Re-order so that the !SvOK() case is last (which should be rare)
2291 =head2 Extend PUSHFORMAT() to take a second parameter to set retop, to save NULLing it and then reassigning.
2293 =head2 Split struct block_sub into struct block_sub and struct block_format.
2295 Split struct block_sub into struct block_sub and struct block_format.
2296 (CXt_SUB and CXt_FORMAT were using some comon members, but some members
2297 were only for one or the other.)
2299 =head2 Change the wantarray result from caller from IV to bool for the SCALAR/ARRAY case.
2301 This doesn't contradict the documentation, as there isn't any. Oops.
2304 =head2 Give G_VOID, G_SCALAR and G_ARRAY the same numeric values as OPf_WANT_VOID, OPf_WANT_SCALAR and OPf_WANT_LIST.
2307 =head2 Squeeze the context type down to 4 bits, and move the private flags to fit within the next 4 bits.
2310 =head2 In struct block change blku_type from U8 to U16, and the "spare" U8 to U16, with the lockstep changes in struct subst.
2312 struct block_sub, and instead store it in the U16 in struct block.
2315 =head2 In struct block_eval, eliminate old_in_eval and old_op_type by storing the data in blk_u16.
2318 =head2 The layout for struct block_loop under ithreads can be simplified.
2320 Instead of wedging the pad offset into a void* iterdata, and always
2321 storing PL_comppad even when it isn't used, instead do this:
2323 PAD *oldcomppad; /* Also used for the GV, if targoffset is 0 */
2324 /* This is also accessible via cx->blk_loop.my_op->op_targ */
2325 PADOFFSET targoffset;
2327 and store the GV pointer in oldcompad. Pointers to pointers seems
2328 cleaner. This also allows us to eliminate the flag bit CXp_PADVAR.
2331 =head2 In XS_PerlIO_get_layers() take advantage of the implementation of
2333 In XS_PerlIO_get_layers() take advantage of the implementation of
2334 PerlIO_get_layers(), by co-opting the new SVs it creates, rather than
2338 =head2 Micro-optimise the order of the context types. [Because I can :-)]
2340 =head2 [patch] optimize OP_IS_(FILETEST|SOCKET) macros
2342 =head2 Eliminate ck_lengthconst.
2344 =head2 Chainsaw DEBUG_S out, as suggested by Vincent Pit.
2346 =head2 Unsupported private API functions are now declared "static" to prevent leakage to the public API
2348 =head2 Perl_cv_ckproto() is not part of the public API, and not used anywhere. It has been removed
2350 =head2 Remove all the 5005threads specific mutex macros, which are now vestigial.
2352 =head2 Do not honor TMPDIR for anonymous temporary files when tainting
2354 Use a default of /tmp on Unixes when TMPDIR is unset or empty, or
2355 when creation of a temporary file in it fails
2357 =head2 Add a pluggable hook in op_free()