=head1 NAME
-perldelta - what is new for perl v5.25.2
+perldelta - what is new for perl v5.25.4
=head1 DESCRIPTION
-This document describes differences between the 5.25.1 release and the 5.25.2
+This document describes differences between the 5.25.3 release and the 5.25.4
release.
-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.
+If you are upgrading from an earlier release such as 5.25.2, first read
+L<perl5253delta>, which describes differences between 5.25.2 and 5.25.3.
-=head1 Core Enhancements
+=head1 Performance Enhancements
-=head2 Perl can now do default collation in UTF-8 locales on platforms
-that support it
-
-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>.
-
-=head2 Lexical subroutines are no longer experimental
-
-Using the C<lexical_subs> feature no longer emits a warning. Existing code that disables the C<experimental::lexical_subs> warning category that the
-feature previously used will continue to work. The C<lexical_subs> feature
-has no effect; all Perl code can use lexical subroutines, regardless of
-what feature declarations are in scope.
-
-=head2 C<CORE> subroutines for hash and array functions callable via
-reference
-
-The hash and array functions in the C<CORE> namespace--C<keys>, C<each>,
-C<values>, C<push>, C<pop>, C<shift>, C<unshift> and C<splice>--, can now
-be called with ampersand syntax (C<&CORE::keys(\%hash>) and via reference
-(C<<my $k = \&CORE::keys; $k->(\%hash) >>). Previously they could only be
-used when inlined.
-
-=head1 Security
-
-=head2 C<-Di> switch is now required for PerlIO debugging output
-
-Previously PerlIO debugging output would be sent to the file specified
-by the C<PERLIO_DEBUG> environment variable if perl wasn't running
-setuid and the C<-T> or C<-t> switches hadn't been parsed yet.
-
-If perl performed output at a point where it hadn't yet parsed its
-switches this could result in perl creating or overwriting the file
-named by C<PERLIO_DEBUG> even when the C<-T> switch had been supplied.
-
-Perl now requires the C<-Di> switch to produce PerlIO debugging
-output. By default this is written to C<stderr>, but can optionally
-be redirected to a file by setting the C<PERLIO_DEBUG> environment
-variable.
-
-If perl is running setuid or the C<-T> switch has supplied
-C<PERLIO_DEBUG> is ignored and the debugging output is sent to
-C<stderr> as for any other C<-D> switch.
-
-=head1 Incompatible Changes
-
-=head2 C<keys> returned from an lvalue subroutine
-
-C<keys> returned from an lvalue subroutine can no longer be assigned
-to in list context.
+=over 4
- sub foo : lvalue { keys(%INC) }
- (foo) = 3; # death
- sub bar : lvalue { keys(@_) }
- (bar) = 3; # also an error
+=item *
-This makes the lvalue sub case consistent with C<(keys %hash) = ...> and
-C<(keys @_) = ...>, which are also errors. [perl #128187]
+The rather slow implementation for the experimental subroutine signatures
+feature has been made much faster; it is now comparable in speed with the
+old-style C<my ($a, $b, @c) = @_>.
-=head1 Modules and Pragmata
+=back
-XXX All changes to installed files in F<cpan/>, F<dist/>, F<ext/> and F<lib/>
-go here. If Module::CoreList is updated, generate an initial draft of the
-following sections using F<Porting/corelist-perldelta.pl>. A paragraph summary
-for important changes should then be added by hand. In an ideal world,
-dual-life modules would have a F<Changes> file that could be cribbed.
+=head1 Documentation
-[ Within each section, list entries as a =item entry ]
+=head2 Changes to Existing Documentation
-=head2 New Modules and Pragmata
+=head3 L<perlcall>
=over 4
=item *
-XXX
+Removed redundant C<dSP> from an example.
=back
+=head1 Modules and Pragmata
+
=head2 Updated Modules and Pragmata
=over 4
=item *
-L<CPAN> has been upgraded from version 2.11 to 2.14.
+L<Archive::Tar> has been upgraded from version 2.08 to 2.10.
=item *
-L<Devel::Peek> has been upgraded from version 1.23 to 1.24.
+L<arybase> has been upgraded from version 0.11 to 0.12.
=item *
-L<diagnostics> has been upgraded from version 1.34 to 1.35.
+L<B> has been upgraded from version 1.62 to 1.63.
=item *
-L<DynaLoader> has been upgraded from version 1.38 to 1.39.
+L<B::Concise> has been upgraded from version 0.996 to 0.998.
=item *
-L<ExtUtils::MakeMaker> has been upgraded from version 7.10_01 to 7.18.
+L<B::Deparse> has been upgraded from version 1.37 to 1.38.
=item *
-L<ExtUtils::Miniperl> has been upgraded from version 1.05 to 1.06.
+L<base> has been upgraded from version 2.23 to 2.24.
=item *
-L<ExtUtils::ParseXS> has been upgraded from version 3.31 to 3.32.
+L<bignum> has been upgraded from version 0.43 to 0.43_01.
=item *
-L<ExtUtils::Typemaps> has been upgraded from version 3.31 to 3.32.
+L<Carp> has been upgraded from version 1.41 to 1.42.
=item *
-L<feature> has been upgraded from version 1.43 to 1.44.
+L<Config::Perl::V> has been upgraded from version 0.26 to 0.27.
=item *
-L<File::Copy> has been upgraded from version 2.31 to 2.32.
+L<CPAN> has been upgraded from version 2.14 to 2.14_01.
=item *
-L<File::Glob> has been upgraded from version 1.26 to 1.27.
+L<CPAN::Meta> has been upgraded from version 2.150005 to 2.150010.
=item *
-L<File::Spec> has been upgraded from version 3.63 to 3.64.
+L<Digest> has been upgraded from version 1.17 to 1.17_01.
=item *
-L<FileHandle> has been upgraded from version 2.02 to 2.03.
+L<Digest::SHA> has been upgraded from version 5.95 to 5.96.
=item *
-L<Getopt::Long> has been upgraded from version 2.48 to 2.49.
+L<Encode> has been upgraded from version 2.84 to 2.86.
=item *
-L<HTTP::Tiny> has been upgraded from version 0.056 to 0.058.
+L<encoding> has been upgraded from version 2.17_01 to 2.18.
=item *
-L<JSON::PP> has been upgraded from version 2.27300 to 2.27400.
+L<Errno> has been upgraded from version 1.25 to 1.26.
=item *
-L<Locale::Codes> has been upgraded from version 3.38 to 3.39.
+L<ExtUtils::MakeMaker> has been upgraded from version 7.18 to 7.24.
=item *
-L<Module::CoreList> has been upgraded from 5.20160520 to 5.20160620.
+L<File::Fetch> has been upgraded from version 0.48 to 0.52.
=item *
-L<Opcode> has been upgraded from version 1.34 to 1.35.
+L<File::Spec> has been upgraded from version 3.64 to 3.65.
=item *
-L<Pod::Checker> has been upgraded from version 1.60 to 1.73.
+L<Hash::Util> has been upgraded from version 0.20 to 0.21.
=item *
-L<Pod::Functions> has been upgraded from version 1.10 to 1.11.
+L<HTTP::Tiny> has been upgraded from version 0.058 to 0.064.
=item *
-L<Pod::Usage> has been upgraded from version 1.68 to 1.69.
+L<I18N::LangTags> has been upgraded from version 0.40 to 0.41.
=item *
-L<POSIX> has been upgraded from version 1.69 to 1.70.
+L<IO> has been upgraded from version 1.36 to 1.37.
=item *
-L<Test::Simple> has been upgraded from version 1.302015 to 1.302026.
+L<IO-Compress> has been upgraded from version 2.069 to 2.069_01.
=item *
-L<Thread::Queue> has been upgraded from version 3.09 to 3.11.
+L<IO::Socket::IP> has been upgraded from version 0.37 to 0.38.
=item *
-L<threads> has been upgraded from version 2.08 to 2.09.
+L<IPC::Cmd> has been upgraded from version 0.94 to 0.96.
=item *
-L<Time::HiRes> has been upgraded from version 1.9733 to 1.9734.
+L<JSON::PP> has been upgraded from version 2.27400 to 2.27400_01.
=item *
-L<Unicode::UCD> has been upgraded from version 0.64 to 0.65.
+L<Locale::Maketext> has been upgraded from version 1.27 to 1.28.
=item *
-L<VMS::DCLsym> has been upgraded from version 1.06 to 1.07.
+L<Locale::Maketext::Simple> has been upgraded from version 0.21 to 0.21_01.
=item *
-L<XXX> has been upgraded from version A.xx to B.yy.
-
-=back
+L<Memoize> has been upgraded from version 1.03 to 1.03_01.
-=head2 Removed Modules and Pragmata
+=item *
-=over 4
+L<Module::CoreList> has been upgraded from version 5.20160720 to 5.20160820.
=item *
-XXX
+L<Module::Load::Conditional> has been upgraded from version 0.64 to 0.68.
-=back
+=item *
-=head1 Documentation
+L<Module::Metadata> has been upgraded from version 1.000032 to 1.000033.
-=head2 Changes to Existing Documentation
-
-=head3 L<perlcommunity>
+=item *
-=over 4
+L<Net::Ping> has been upgraded from version 2.43 to 2.44.
=item *
-All references to Usenet have been removed.
-
-=back
+L<NEXT> has been upgraded from version 0.65 to 0.67.
-=head3 L<perldelta>
+=item *
-=over 4
+L<Opcode> has been upgraded from version 1.35 to 1.37.
=item *
-All references to Usenet have been removed.
+L<Pod::Html> has been upgraded from version 1.22 to 1.2201.
-=back
-
-=head3 L<perllocale>
+=item *
-=over 4
+L<Pod::Perldoc> has been upgraded from version 3.25_02 to 3.27.
=item *
-Document NUL collation handling.
-
-=back
+L<POSIX> has been upgraded from version 1.70 to 1.71.
-=head3 L<perlmodinstall>
+=item *
-=over 4
+L<Storable> has been upgraded from version 2.56 to 2.57.
=item *
-All references to Usenet have been removed.
-
-=back
+L<Sys::Syslog> has been upgraded from version 0.34 to 0.34_01.
-=head3 L<perlmodlib>
+=item *
-=over 4
+L<Test> has been upgraded from version 1.28 to 1.29.
=item *
-Updated the mirror list.
+L<Test::Harness> has been upgraded from version 3.36 to 3.36_01.
=item *
-All references to Usenet have been removed.
+L<Test::Simple> has been upgraded from version 1.302045 to 1.302052.
-=back
-
-=head3 L<perlnewmod>
+=item *
-=over 4
+L<Tie::Hash::NamedCapture> has been upgraded from version 0.09 to 0.10.
=item *
-All references to Usenet have been removed.
+L<Time::Local> has been upgraded from version 1.2300 to 1.24.
=back
-=head1 Diagnostics
-
-The following additions or changes have been made to diagnostic output,
-including warnings and fatal error messages. For the complete list of
-diagnostic messages, see L<perldiag>.
-
-=head2 New Diagnostics
-
-=head3 New Errors
+=head1 Configuration and Compilation
=over 4
=item *
-L<Version control conflict marker|perldiag/"Version control conflict marker">
-
-(F) The parser found a line starting with C<E<lt><<<<<<>,
-C<E<gt>E<gt>E<gt>E<gt>E<gt>E<gt>E<gt>>, or C<=======>. These may be left by a
-version control system to mark conflicts after a failed merge operation.
-
-=item *
-
-L<%s: command not found|perldiag/"%s: command not found">
+A probe for C<gai_strerror> was added to F<Configure> that checks if the
+the gai_strerror() routine is available and can be used to
+translate error codes returned by getaddrinfo() into human
+readable strings.
-(A) You've accidentally run your script through B<bash> or another shell
-instead of Perl. Check the #! line, or manually feed your script into
-Perl yourself. The #! line at the top of your file could look like
-
- #!/usr/bin/perl
-
-=item *
-
-L<%s: command not found: %s|perldiag/"%s: command not found: %s">
+=back
-(A) You've accidentally run your script through B<zsh> or another shell
-instead of Perl. Check the #! line, or manually feed your script into
-Perl yourself. The #! line at the top of your file could look like
+=head1 Platform Support
- #!/usr/bin/perl
+=head2 Platform-Specific Notes
-=item *
+=over 4
-L<Unescaped left brace in regex is deprecated here, passed through in regex; marked by S<<-- HERE> in mE<sol>%sE<sol>|perldiag/"Unescaped left brace in regex is deprecated here, passed through in regex; marked by S<<-- HERE> in m/%s/">
+=item Hurd
-Unescaped left braces are already illegal in some contexts in regular
-expression patterns, but, due to an oversight, no deprecation warning
-was raised in other contexts where they are intended to become illegal.
-This warning is now raised in these contexts.
+The hints for Hurd have been improved enabling malloc wrap and reporting the
+GNU libc used (previously it was an empty string when reported).
=back
-=head2 Changes to Existing Diagnostics
+=head1 Internal Changes
=over 4
=item *
-L<Unescaped left brace in regex is illegal here in regex; marked by S<<-- HERE> in mE<sol>%sE<sol>|perldiag/"Unescaped left brace in regex is illegal here in regex; marked by S<<-- HERE> in m/%s/">
-
-The word "here" has been added to the message that was raised in
-v5.25.1. This is to indicate that there are contexts in which unescaped
-left braces are not (yet) illegal.
+Three new ops, C<OP_ARGELEM>, C<OP_ARGDEFELEM> and C<OP_ARGCHECK> have
+been added. These are intended principally to implement the individual
+elements of a subroutine signature, plus any overall checking required.
=back
-=head1 Configuration and Compilation
+=head1 Selected Bug Fixes
=over 4
=item *
-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]
+Problems with in-place array sorts: code like C<@a = sort { ... } @a>,
+where the source and destination of the sort are the same plain array, are
+optimised to do less copying around. Two side-effects of this optimisation
+were that the contents of C<@a> as visible to to sort routine were
+partially sorted, and under some circumstances accessing C<@a> during the
+sort could crash the interpreter. Both these issues have been fixed, and
+Sort functions see the original value of C<@a>.
=item *
-The output of C<perl -V> has been reformatted so that each configuration
-and compile-time option is now listed one per line, to improve
-readability.
+Non-ASCII string delimiters are now reported correctly in error messages
+for unterminated strings. [perl #128701]
-=back
+=item *
-=head1 Testing
-
-=over 4
+C<pack("p", ...)> used to emit its warning ("Attempt to pack pointer to
+temporary value") erroneously in some cases, but has been fixed.
=item *
-F<t/harness> now tries really hard not to run tests outside of the Perl
-source tree. [perl #124050]
-
-=back
+C<@DB::args> is now exempt from "used once" warnings. The warnings only
+occurred under B<-w>, because F<warnings.pm> itself uses C<@DB::args>
+multiple times.
-=head1 Internal Changes
+=item *
-=over 4
+The use of built-in arrays or hash slices in a double-quoted string no
+longer issues a warning ("Possible unintended interpolation...") if the
+variable has not been mentioned before. This affected code like
+C<qq|@DB::args|> and C<qq|@SIG{'CHLD', 'HUP'}|>. (The special variables
+C<@-> and C<@+> were already exempt from the warning.)
=item *
-Perl no longer panics when switching into some locales on machines with
-buggy C<strxfrm()> implementations in their libc. [perl #121734]
+C<gethostent> and similar functions now perform a null check internally, to
+avoid crashing with torsocks. This was a regression from 5.22. [perl
+#128740]
-=back
+=item *
-=head1 Selected Bug Fixes
+C<defined *{'!'}>, C<defined *{'['}>, and C<defined *{'-'}> no longer leak
+memory if the typeglob in question has never been accessed before.
-=over 4
+=item *
+
+In 5.25.4 fchown() was changed not to accept negative one as an argument
+because in some platforms that is an error. However, in some other platforms
+that is an acceptable argument. This change has been reverted [perl #128967].
=item *
-C< until ($x = 1) { ... } > and C< ... until $x = 1 > now properly
-warn when syntax warnings are enabled. [perl #127333]
+Mentioning the same constant twice in a row (which is a syntax error) no
+longer fails an assertion under debugging builds. This was a regression
+from 5.20. [perl #126482]
=item *
-socket() now leaves the error code returned by the system in C<$!> on
-failure. [perl #128316]
+Many issues relating to C<printf "%a"> of hexadecimal floating point
+were fixed. In addition, the "subnormals" (formerly known as "denormals")
+floating point anumbers are now supported both with the plain IEEE 754
+floating point numbers (64-bit or 128-bit) and the x86 80-bit
+"extended precision". Note that subnormal hexadecimal floating
+point literals will give a warning about "exponent underflow".
+[perl #128843, #128889, #128890, #128893, #128909, #128919]
=item *
-Assignment variants of any bitwise ops under the C<bitwise> feature would
-crash if the left-hand side was an array or hash. [perl #128204]
+A regression in 5.24 with C<tr/\N{U+...}/foo/> when the code point was between
+128 and 255 has been fixed. [perl #128734].
=item *
-C<require> followed by a single colon (as in C<foo() ? require : ...> is
-now parsed correctly as C<require> with implicit $_, rather than
-C<require "">. [perl #128307]
+A regression from the previous development release, 5.23.3, where
+compiling a regular expression could crash the interpreter has been
+fixed. [perl #128686].
=item *
-Scalar C<keys %hash> can now be assigned to consistently in all scalar
-lvalue contexts. Previously it worked for some contexts but not others.
+Use of a string delimiter whose code point is above 2**31 now works
+correctly on platforms that allow this. Previously, certain characters,
+due to truncation, would be confused with other delimiter characters
+with special meaning (such as C<?> in C<m?...?>), resulting
+in inconsistent behaviour. Note that this is non-portable,
+and is based on Perl's extension to UTF-8, and is probably not
+displayable nor enterable by any editor. [perl #128738]
=item *
-List assignment to C<vec> or C<substr> with an array or hash for its first
-argument used to result in crashes or "Can't coerce" error messages at run
-time, unlike scalar assignment, which would give an error at compile time.
-List assignment now gives a compile-time error, too. [perl #128260]
+C<@{x> followed by a newline where C<x> represents a control or non-ASCII
+character no longer produces a garbled syntax error message or a crash.
+[perl #128951]
=back
=head1 Acknowledgements
-Perl 5.25.2 represents approximately 4 weeks of development since Perl 5.25.1
-and contains approximately 32,000 lines of changes across 430 files from 28
+Perl 5.25.4 represents approximately 4 weeks of development since Perl 5.25.3
+and contains approximately 18,000 lines of changes across 820 files from 23
authors.
Excluding auto-generated files, documentation and release tools, there were
-approximately 27,000 lines of changes to 300 .pm, .t, .c and .h files.
+approximately 9,200 lines of changes to 660 .pm, .t, .c and .h files.
Perl continues to flourish into its third decade thanks to a vibrant community
of users and developers. The following people are known to have contributed the
-improvements that became Perl 5.25.2:
-
-Aaron Crane, Andreas König, Andy Lester, Chad Granum, Chase Whitener, Chris
-'BinGOs' Williams, Craig A. Berry, Dagfinn Ilmari Mannsåker, Dan Collins,
-David Mitchell, Dominic Hargreaves, Ed Avis, Father Chrysostomos, H.Merijn
-Brand, Ivan Pozdeev, James E Keenan, Jarkko Hietaniemi, Jerry D. Hedden, Jim
-Cromie, Karl Williamson, Lukas Mai, Matthew Horsfall, Misty De Meo, Samuel
-Thibault, Sawyer X, Sullivan Beck, Tony Cook, Yves Orton.
+improvements that became Perl 5.25.4:
+
+Chris 'BinGOs' Williams, Craig A. Berry, Dagfinn Ilmari Mannsåker, Dan
+Collins, Daniel Dragan, David Mitchell, Father Chrysostomos, H.Merijn Brand,
+James E Keenan, Jarkko Hietaniemi, Karen Etheridge, Karl Williamson, Lukas Mai,
+Neil Bowers, Nicolas R., Pino Toscano, Rafael Garcia-Suarez, Richard Levitte,
+Shlomi Fish, Smylers, Steve Hay, Tony Cook, Yves Orton.
The list above is almost certainly incomplete as it is automatically generated
from version control history. In particular, it does not include the names of
https://perl5.git.perl.org / perl5.git / blobdiff