[ this is a template for a new perldelta file. Any text flagged as XXX needs
to be processed before release. ]
-perldelta - what is new for perl v5.23.8
+perldelta - what is new for perl v5.25.2
=head1 DESCRIPTION
-This document describes differences between the 5.23.7 release and the 5.23.8
+This document describes differences between the 5.25.1 release and the 5.25.2
release.
-If you are upgrading from an earlier release such as 5.23.6, first read
-L<perl5237delta>, which describes differences between 5.23.6 and 5.23.7.
+If you are upgrading from an earlier release such as 5.25.0, first read
+L<perl5251delta>, which describes differences between 5.25.0 and 5.25.1.
=head1 Notice
[ List each enhancement as a =head2 entry ]
-=head2 More fields provided to C<sigaction> callback with C<SA_SIGINFO>
+=head2 Perl can now do default collation in UTF-8 locales on platforms
+that support it
-When passing the C<SA_SIGINFO> flag to L<sigaction|POSIX/sigaction>, the
-C<errno>, C<status>, C<uid>, C<pid>, C<addr> and C<band> fields are now
-included in the hash passed to the handler, if supported by the
-platform.
+Some platforms natively do a reasonable job of collating and sorting in
+UTF-8 locales. Perl now works with those. For portability and full
+control, L<Unicode::Collate> is still recommended, but now you may
+not need to do anything special to get good-enough results, depending on
+your application. See
+L<perllocale/Category C<LC_COLLATE>: Collation: Text Comparisons and Sorting>
+
+=head2 Better locale collation of strings containing embedded C<NUL>
+characters
+
+In locales that have multi-level character weights, these are now
+ignored at the higher priority ones. There are still some gotchas in
+some strings, though. See
+L<perllocale/Collation of strings containing embedded C<NUL> characters>.
=head1 Security
[ List each security issue as a =head2 entry ]
+=head2 C<-Di> switch is now required for PerlIO debugging output
+
+Previously PerlIO debugging output would be sent to the file specified
+by the C<PERLIO_DEBUG> environment variable if perl wasn't running
+setuid and the C<-T> or C<-t> switches hadn't been parsed yet.
+
+If perl performed output at a point where it hadn't yet parsed its
+switches this could result in perl creating or overwriting the file
+named by C<PERLIO_DEBUG> even when the C<-T> switch had been supplied.
+
+Perl now requires the C<-Di> switch to produce PerlIO debugging
+output. By default this is written to C<stderr>, but can optionally
+be redirected to a file by setting the C<PERLIO_DEBUG> environment
+variable.
+
+If perl is running setuid or the C<-T> switch has supplied
+C<PERLIO_DEBUG> is ignored and the debugging output is sent to
+C<stderr> as for any other C<-D> switch.
+
=head1 Incompatible Changes
XXX For a release on a stable branch, this section aspires to be:
=item *
-The overhead of scope entry and exit has been considerably reduced, so
-for example subroutine calls, loops and basic blocks are all faster now.
-This empty function call now takes about a third less time to execute:
-
- sub f{} f();
+XXX
=back
=item *
-F<cpan/podlators/> has been upgraded from version 4.04 to 4.06.
+L<XXX> has been upgraded from version A.xx to B.yy.
=item *
-L<POSIX> has been upgraded from version 1.59 to 1.60.
-
-It can now export constants for the C<code> value in the hash passed to the
-L<sigaction|POSIX/sigaction> handler when using the C<SA_SIGINFO> flag.
+L<Module::CoreList> has been upgraded from 5.20160520 to 5.20160620.
=back
However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
section.
-=head3 L<perlguts>
+=head3 L<XXX>
=over 4
=item *
-A new section has been added, L<perlguts/"Dynamic Scope and the Context
-Stack">, which explains how the perl context stack works.
+XXX Description of the change here
=back
=item *
+L<Version control conflict marker|perldiag/"Version control conflict marker">
+
+=item *
+
XXX L<message|perldiag/"message">
=back
=item *
-XXX
+F<make_ext.pl> no longer updates a module's F<pm_to_blib> file when no
+files require updates. This could cause dependencies, F<perlmain.c>
+in particular, to be rebuilt unnecessarily. [perl #126710]
=back
XXX
-=item *
-
-The GNU Make makefile for Win32 now supports parallel builds. [perl #126632]
-
-=item *
-
-You can now build perl with MSVC++ on Win32 using GNU Make. [perl #126632]
-
=back
=head1 Platform Support
-=head2 Platform-Specific Notes
-
-=over 4
-
-=item VMS
+XXX Any changes to platform support should be listed in the sections below.
-=over
-
-=item *
-
-For those C<%ENV> elements based on the CRTL environ array, we've always
-preserved case when setting them but did look-ups only after upcasing the
-key first, which made lower- or mixed-case entries go missing. This problem
-has been corrected by making C<%ENV> elements derived from the environ array
-case-sensitive on look-up as well as case-preserving on store.
-
-=item *
-
-Environment look-ups for C<PERL5LIB> and C<PERLLIB> previously only
-considered logical names, but now consider all sources of C<%ENV> as
-determined by C<PERL_ENV_TABLES> and as documented in L<perlvms/%ENV>.
-
-=back
-
-=back
+[ Within the sections, list each platform as a =item entry with specific
+changes as paragraphs below it. ]
=head2 New Platforms
=over 4
-=item Win32
+=item XXX-some-platform
-Builds using Microsoft Visual C++ 2003 and earlier no longer produce
-an "INTERNAL COMPILER ERROR" message. [perl #126045]
+XXX
=back
=item *
-The implementation of perl's context stack system, and its internal API,
-have been heavily reworked. Note that no significant changes have been
-made to any external APIs, but XS code which relies on such internal
-details may need to be fixed. The main changes are:
-
-=over 4
-
-=item *
-
-The C<PUSHBLOCK()>, C<POPSUB()> etc. macros have been replaced with static
-inline functions such as C<cx_pushblock()>, C<cx_popsub()> etc. These use
-function args rather than implicitly relying on local vars such as
-C<gimme> and C<newsp> being available. Also their functionality has
-changed: in particular, C<cx_popblock()> no longer decrements
-C<cxstack_ix>. The ordering of the steps in the C<pp_leave*> functions
-involving C<cx_popblock()>, C<cx_popsub()> etc. has changed. See the new
-documentation, L<perlguts/"Dynamic Scope and the Context Stack">, for
-details on how to use them.
-
-=item *
-
-Various macros, which now consistently have a CX_ prefix, have been added:
-
- CX_CUR(), CX_LEAVE_SCOPE(), CX_POP()
-
-or renamed:
-
- CX_POP_SAVEARRAY(), CX_DEBUG(), CX_PUSHSUBST() ,CX_POPSUBST()
-
-=item *
-
-C<cx_pushblock()> now saves C<PL_savestack_ix> and C<PL_tmps_floor>, so
-CMpp_enter*> and C<pp_leave*> no longer do
-
- ENTER; SAVETMPS; ....; LEAVE
-
-=item *
-
-C<cx_popblock()> now also restores C<PL_curpm>.
-
-=item *
-
-In C<dounwind()> for every context type, the current savestack frame is
-now processed before each context is popped; formerly this was only done
-for sub-like context frames. This action has been removed from
-C<cx_popsub()> and placed into its own macro, C<CX_LEAVE_SCOPE(cx)>, which
-must be called before C<cx_popsub()> etc.
-
-C<dounwind()> now also does a C<cx_popblock()> on the last popped frame
-(formerly it only did the C<cx_popsub()> etc. actions on each frame).
-
-=item *
-
-The temps stack is now freed on scope exit; previously, temps created
-during the last statement of a block wouldn't be freed until the next
-C<nextstate> following the block (apart from an existing hack that did
-this for recursive subs in scalar context); and in something like
-C<f(g())>, the temps created by the last statement in C<g()> would
-formerly not be freed until the statement following the return from
-C<f()>.
-
-=item *
-
-Most values that were saved on the savestack on scope entry are now
-saved in suitable new fields in the context struct, and saved and
-restored directly by C<cx_pushfoo()> and C<cx_popfoo()>, which is much
-faster.
-
-=item *
-
-Various context struct fields have been added, removed or modified.
-
-=item *
-
-The handling of C<@_> in C<cx_pushsub()> and C<cx_popsub()> has been
-considerably tidied up, including removing the C<argarray> field from the
-context struct, and extracting out some common (but rarely used) code into
-a separate function, C<clear_defarray()>. Also, useful subsets of
-C<cx_popsub()> which had been unrolled in places like C<pp_goto> have been
-gathered into the new functions C<cx_popsub_args()> and
-C<cx_popsub_common()>.
-
-=item *
-
-C<pp_leavesub> and C<pp_leavesublv> now use the same function as the rest
-of the C<pp_leave*>'s to process return args.
-
-=item *
-
-C<CXp_FOR_PAD> and C<CXp_FOR_GV> flags have been added, and
-C<CXt_LOOP_FOR> has been split into C<CXt_LOOP_LIST>, C<CXt_LOOP_ARY>.
-
-=item *
-
-Some variables formerly declared by C<dMULTICALL> (but not documented) have
-been removed.
-
-=back
-
+Perl no longer panics when switching into some locales on machines with
+buggy C<strxfrm()> implementations in their libc. [perl #121734]
=back
=item *
-Line numbers larger than 2**31-1 but less than 2**32 are no longer
-returned by caller() as negative numbers. [perl #126991]
-
-=item *
-
-C<< unless ( I<assignment> ) >> now properly warns when syntax
-warnings are enabled. [perl #127122]
-
-=item *
-
-Setting an C<ISA> glob to an array reference now properly adds
-C<isaelem> magic to any existing elements. Previously modifying such
-an element would not update the ISA cache, so method calls would call
-the wrong function. Perl would also crash if the C<ISA> glob was
-destroyed, since new code added in 5.23.7 would try to release the
-C<isaelem> magic from the elements. [perl #127351]
-
-=item *
-
-If a here-doc was found while parsing another operator, the parser had
-already read end of file, and the here-doc was not terminated, perl
-could produce an assertion or a segmentation fault. This now reliably
-complains about the unterminated here-doc. [perl #125540]
-
-=item *
-
-untie() would sometimes return the last value returned by the UNTIE()
-handler as well as it's normal value, messing up the stack. [perl
-#126621]
-
-=item *
-
-Fixed an operator precedence problem when C< castflags & 2> is true.
-[perl #127474]
+C< until ($x = 1) { ... } > and C< ... until $x = 1 > now properly
+warn when syntax warnings are enabled. [perl #127333]
=back
XXX Generate this with:
- perl Porting/acknowledgements.pl v5.23.7..HEAD
+ perl Porting/acknowledgements.pl v5.25.1..HEAD
=head1 Reporting Bugs
sufficient test case. Your bug report, along with the output of C<perl -V>,
will be sent off to perlbug@perl.org to be analysed by the Perl porting team.
-If the bug you are reporting has security implications, which make it
-inappropriate to send to a publicly archived mailing list, then please send it
-to perl5-security-report@perl.org. This points to a closed subscription
-unarchived mailing list, which includes all the core committers, who will be
-able to help assess the impact of issues, figure out a resolution, and help
-co-ordinate the release of patches to mitigate or fix the problem across all
-platforms on which Perl is supported. Please only use this address for
-security issues in the Perl core, not for modules independently distributed on
-CPAN.
+If the bug you are reporting has security implications which make it
+inappropriate to send to a publicly archived mailing list, then see
+L<perlsec/SECURITY VULNERABILITY CONTACT INFORMATION>
+for details of how to report the issue.
=head1 SEE ALSO
https://perl5.git.perl.org / perl5.git / blobdiff