=head1 NAME
-[ 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 v5.25.1
=head1 DESCRIPTION
-This document describes differences between the 5.23.7 release and the 5.23.8
+This document describes differences between the 5.25.0 release and the 5.25.1
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 5.24.0, first read
+L<perl5250delta>, which describes differences between 5.24.0 and 5.25.0.
=head1 Notice
[ List each security issue as a =head2 entry ]
-=head1 Incompatible Changes
+=head2 require ::Foo::Bar is now illegal.
+
+Formerly, C<require ::Foo::Bar> would try to read F</Foo/Bar.pm>. Now any
+bareword require which starts with a double colon dies instead.
+
+=head2 Unescaped literal C<"{"> characters in regular expression
+patterns are no longer permissible
+
+You have to now say something like C<"\{"> or C<"[{]"> to specify to
+match a LEFT CURLY BRACKET. This will allow future extensions to the
+language. This restriction is not enforced, nor are there current plans
+to enforce it, if the C<"{"> is the first character in the pattern.
+
+These have been deprecated since v5.16, with a deprecation message
+displayed starting in v5.22.
-XXX For a release on a stable branch, this section aspires to be:
+=head2 Literal control character variable names are no longer permissible
- There are no changes intentionally incompatible with 5.XXX.XXX
- If any exist, they are bugs, and we request that you submit a
- report. See L</Reporting Bugs> below.
+A variable name may no longer contain a literal control character under
+any circumstances. These previously were allowed in single-character
+names on ASCII platforms, but have been deprecated there since Perl
+v5.20. This affects things like C<$I<\cT>>, where I<\cT> is a literal
+control (such as a C<NAK> or C<NEGATIVE ACKNOWLEDGE> character) in the
+source code.
-[ List each incompatible change as a =head2 entry ]
+=head2 C<qr//xx> is no longer permissible
+
+Using more than one C</x> regular expression pattern modifier on a
+single pattern is now forbidden. This is to allow a future enhancement
+to the language. This usage has been deprecated since v5.22.
+
+=head2 C<NBSP> is no longer permissible in C<\N{...}>
+
+The name of a character may no longer contain non-breaking spaces. It
+has been deprecated to do so since Perl v5.22.
=head1 Deprecations
=item *
-XXX
+Bareword constant strings are now permitted to take part in constant
+folding. They were originally exempted from constant folding in August 1999,
+during the development of Perl 5.6, to ensure that C<use strict "subs">
+would still apply to bareword constants. That has now been accomplished a
+different way, so barewords, like other constants, now gain the performance
+benefits of constant folding.
+
+This also means that void-context warnings on constant expressions of
+barewords now report the folded constant operand, rather than the operation;
+this matches the behaviour for non-bareword constants.
=back
=item *
-L<XXX> has been upgraded from version A.xx to B.yy.
+L<POSIX> has been upgraded from version 1.68 to 1.69. This remedies several
+defects in making its symbols exportable. [perl #127821]
=back
=item *
-XXX L<message|perldiag/"message">
+L<Bareword in require contains "%s"|perldiag/"Bareword in require contains "%s"">
+
+=item *
+
+L<Bareword in require maps to empty filename|perldiag/"Bareword in require maps to empty filename">
+
+=item *
+
+L<Bareword in require maps to disallowed filename "%s"|perldiag/"Bareword in require maps to disallowed filename "%s"">
+
+=item *
+
+L<Bareword in require must not start with a double-colon: "%s"|perldiag/"Bareword in require must not start with a double-colon: "%s"">
=back
=item *
-XXX Describe change here
+Code like C<$x = $x . "a"> was incorrectly failing to yield a
+L<use of uninitialized value|perldiag/"Use of uninitialized value%s">
+warning when C<$x> was a lexical variable with an undefined value. That has
+now been fixed. [perl #127877]
=back
entries for each change
Use L<XXX> with program names to get proper documentation linking. ]
-=head2 L<XXX>
+=head2 L<perlbug>
=over 4
=item *
-XXX
+Long lines in the message body are now wrapped at 900 characters, to stay
+well within the 1000-character limit imposed by SMTP mail transfer agents.
+This is particularly likely to be important for the list of arguments to
+C<Configure>, which can readily exceed the limit if, for example, it names
+several non-default installation paths. This change also adds the first unit
+tests for perlbug. [perl #128020]
=back
=item *
-XXX
+C<Configure> now builds C<miniperl> and C<generate_uudmap> if you
+invoke it with C<-Dusecrosscompiler> but not C<-Dtargethost=somehost>.
+This means you can supply your target platform C<config.sh>, generate
+the headers and proceed to build your cross-target perl. [perl #127234]
+
+=item *
+
+Builds with C<-Accflags=-DPERL_TRACE_OPS> now only dump the operator
+counts when the environment variable C<PERL_TRACE_OPS> to be set to a
+non-zero integer. This allows C<make test> to pass on such a build.
+
+=item *
+
+When building with GCC 6 and link-time optimization (the C<-flto> option to
+C<gcc>), C<Configure> was treating all probed symbols as present on the
+system, regardless of whether they actually exist. This has been fixed.
+[perl #128131]
+
+=item *
+
+The F<t/test.pl> library is used for internal testing of Perl itself, and
+also copied by several CPAN modules. Some of those modules must work on
+older versions of Perl, so F<t/test.pl> must in turn avoid newer Perl
+features. Compatibility with Perl 5.8 was inadvertently removed some time
+ago; it has now been restored. [perl #128052]
+
+=item *
+
+The build process no longer emits an extra blank line before building each
+"simple" extension (those with only F<*.pm> and F<*.pod> files).
=back
=item *
-XXX
+Perl is now built with the C<PERL_OP_PARENT> compiler define enabled by
+default. To disable it, use the C<PERL_NO_OP_PARENT> compiler define.
+This flag alters how the C<op_sibling> field is used in C<OP> structures,
+and has been available optionally since perl 5.22.0.
+
+See L<perl5220delta/"Internal Changes"> for more details of what this
+build option does.
=back
=item *
-Line numbers larger than 2**31-1 but less than 2**32 are not longer
-returned by caller() as negative numbers. [perl #126991]
+Expressions containing an C<&&> or C<||> operator (or their synonyms C<and>
+and C<or>) were being compiled incorrectly in some cases. If the left-hand
+side consisted of either a negated bareword constant or a negated C<do {}>
+block containing a constant expression, and the right-hand side consisted of
+a negated non-foldable expression, one of the negations was effectively
+ignored. The same was true of C<if> and C<unless> statement modifiers,
+though with the left-hand and right-hand sides swapped. This long-standing
+bug has now been fixed. [perl #127952]
=back
=head1 Acknowledgements
-XXX Generate this with:
+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