=encoding utf8
+=for comment
+To do:
+df8c7dee Fix segfault in filehandle duplication
+b66f3475 Fix PerlIO_get_cnt and friends
+e94bb470 install useful Regexp::CARP_TRACE from Carp
+9d32676e [perl #117265] fix various problems with safesyscalls
+531d75b0 [perl #89502]: Add support for Atari FreeMiNT platform
+
=head1 NAME
[ this is a template for a new perldelta file. Any text flagged as XXX needs
[ List each enhancement as a =head2 entry ]
-=head2 rand() now uses a consistent random number generator
+=head2 C<rand> now uses a consistent random number generator
+
+Previously perl would use a platform specific random number generator, varying
+between the libc rand(), random() or drand48().
+
+This meant that the quality of perl's random numbers would vary from platform
+to platform, from the 15 bits of rand() on Windows to 48-bits on POSIX
+platforms such as Linux with drand48().
+
+Perl now uses its own internal drand48() implementation on all platforms. This
+does not make perl's C<rand> cryptographically secure. [perl #115928]
+
+=head2 Better 64-bit support
+
+On 64-bit platforms, the internal array functions now use 64-bit offsets,
+allowing Perl arrays to hold more than 2**31 elements, if you have the memory
+available.
-Previously perl would use a platform specific random number generator,
-varying between the libc C<rand()>, C<random()> or C<drand48()>.
+The regular expression engine now supports strings longer than 2**31
+characters. [perl #112790, #116907]
-This meant that the quality of perl's random numbers would vary from
-platform to platform, from the 15 bits of C<rand()> on Win32 to
-48-bits on POSIX platforms such as Linux with C<drand48()>.
+=head2 New slice syntax
-Perl now uses its own internal C<drand48()> implementation on all
-platforms. [perl #115928]
+The new C<%hash{...}> and C<%array[...]> syntax returns a list of key/value (or
+index/value) pairs.
+
+=head2 EBCDIC support
+
+Core Perl now mostly works on EBCDIC platforms. This is not true of many
+modules, including some which are shipped with this release. If you have
+resources to help continue this process, including test machines, send email to
+L<mailto:perl-mvs@perl.org>.
+
+As a result of this, certain XS functions are now deprecated; see L</Internal
+Changes>.
=head1 Security
=head1 Incompatible Changes
=head2 Locale decimal point character no longer leaks outside of
-S<C<use locale>> scope (with the exception of C<$!>)
+S<C<use locale>> scope (with the exception of $!)
This is actually a bug fix, but some code has come to rely on the bug being
present, so this change is listed here. The current locale that the program is
S<C<use locale>>. If your code is affected by this change, simply add a
S<C<use locale>>.
-Now, the only known place where C<'use locale'> is not respected is in the
+Now, the only known place where S<C<use locale>> is not respected is in the
stringification of L<$!|perlvar/$!>.
+=head2 Assignments of Windows sockets error codes to $! now prefer F<errno.h> values over WSAGetLastError() values
+
+In previous versions of Perl, Windows sockets error codes as returned by
+WSAGetLastError() were assigned to $!, and some constants such as ECONNABORTED,
+not in F<errno.h> in VC++ (or the various Windows ports of gcc) were defined to
+corresponding WSAE* values to allow $! to be tested against the E* constants
+exported by L<Errno> and L<POSIX>.
+
+This worked well until VC++ 2010 and later, which introduced new E* constants
+with values E<gt> 100 into F<errno.h>, including some being (re)defined by perl
+to WSAE* values. That caused problems when linking XS code against other
+libraries which used the original definitions of F<errno.h> constants.
+
+To avoid this incompatibility, perl now maps WSAE* error codes to E* values
+where possible, and assigns those values to $!. The E* constants exported by
+L<Errno> and L<POSIX> are updated to match so that testing $! against them,
+wherever previously possible, will continue to work as expected, and all E*
+constants found in F<errno.h> are now exported from those modules with their
+original F<errno.h> values
+
+In order to avoid breakage in existing Perl code which assigns WSAE* values to
+$!, perl now intercepts the assignment and performs the same mapping to E*
+values as it uses internally when assigning to $! itself.
+
+However, one backwards-incompatibility remains: existing Perl code which
+compares $! against the numeric values of the WSAE* error codes that were
+previously assigned to $! will now be broken in those cases where a
+corresponding E* value has been assigned instead. This is only an issue for
+those E* values E<lt> 100, which were always exported from L<Errno> and
+L<POSIX> with their original F<errno.h> values, and therefore could not be used
+for WSAE* error code tests (e.g. WSAEINVAL is 10022, but the corresponding
+EINVAL is 22). (E* values E<gt> 100, if present, were redefined to WSAE*
+values anyway, so compatibility can be achieved by using the E* constants,
+which will work both before and after this change, albeit using different
+numeric values under the hood.)
+
=head1 Deprecations
-XXX Any deprecated features, syntax, modules etc. should be listed here.
+=head2 Literal control characters in variable names
+
+This deprecation affects things like $\cT, where \cT is a literal control in
+the source code. Surprisingly, it appears that originally this was intended as
+the canonical way of accessing variables like $^T, with the caret form only
+being added as an alternative.
+
+The literal control form is being deprecated for two main reasons. It has what
+are likely unfixable bugs, such as $\cI not working as an alias for $^I, and
+their usage not being portable to non-ASCII platforms: While $^T will work
+everywhere, \cT is whitespace in EBCDIC.
=head2 Module removals
The fix for [perl #118525] introduced a regression in the behaviour of
C<B::CV::GV>, changing the return value from a C<B::SPECIAL> object on a
-C<NULL> C<CvGV> to C<undef>. C<B::CV::GV> again returns a C<B::SPECIAL>
-object in this case. [perl #119351]
+C<NULL> C<CvGV> to C<undef>. C<B::CV::GV> again returns a C<B::SPECIAL> object
+in this case. [perl #119351]
+
+B version 1.44 (Perl 5.19.2) introduced four new B::OP methods, C<slabbed>,
+C<savefree>, C<static> and C<folded>, but these have never actually worked
+until now. They used to croak.
=item *
L<B::Concise> has been upgraded from version 0.98 to 0.99.
-The handling of the C<glob> operator, broken since Perl 5.17.6, has been fixed.
+The handling of the C<glob> operator, broken since Perl 5.17.6, has been fixed
+and handling of the new kvaslice and kvhslice operators have been added.
+
+=item *
+
+L<B::Deparse> has been upgraded from version 1.22 to 1.23.
+
+The new kvaslice and kvhslice operators have been added.
=item *
=item *
+C<Carp> now takes care not to clobber the status variables $! and $^E.
+
+=item *
+
C<Carp> now won't vivify the C<overload::StrVal> glob or subroutine or the
C<overload> stash.
=item *
C<Carp> now avoids some unwanted Unicode warnings on older Perls. This doesn't
-affect behaviour with current Perl.
+affect behaviour with current Perls.
=item *
=item *
+L<CPAN> has been upgraded from version 2.00 to 2.03-TRIAL.
+
+Numerous updates and bug fixes are incorporated. See the F<Changes> file for
+full details.
+
+=item *
+
L<CPAN::Meta> has been upgraded from version 2.132140 to 2.132510.
No changes have been made to the installed code other than the version bump to
=item *
+L<diagnostics> has been upgraded from version 1.32 to 1.33.
+
+C<=back> is now treated as the end of a warning description, thus keeping any
+trailing data in the file from showing up as part of the last warning's
+description. [perl #119817]
+
+=item *
+
L<DynaLoader> has been upgraded from version 1.19 to 1.20.
The documentation now makes it clear, as has always been the case, that
=item *
+L<Errno> has been upgraded from version 1.19 to 1.20.
+
+The list of E* constants exported on Windows has been updated to reflect the
+changes made in the assignment of sockets error codes to $! (see
+L</Incompatible Changes>).
+
+=item *
+
L<Exporter> has been upgraded from version 5.69 to 5.70.
A number of typos have been corrected in the documentation.
=item *
-L<ExtUtils::ParseXS> has been upgraded from version 3.21 to 3.22.
+L<ExtUtils::ParseXS> has been upgraded from version 3.21 to 3.23.
-No changes have been made to the installed code other than the version bump to
-keep in sync with the latest CPAN release.
+Unquoted "here-doc" markers for typemaps can now be optionally followed by a
+semicolon, just like quoted markers. [perl #119761]
=item *
L<File::Glob> has been upgraded from version 1.20 to 1.21.
-C<glob()> now warns in the context of C<use warnings "syscalls";> if the
-supplied pattern has an internal NUL (C<"\0">) character.
+C<glob> now warns in the context of C<use warnings "syscalls";> if the supplied
+pattern has an internal NUL (C<"\0">) character.
+
+=item *
+
+L<FileCache> has been upgraded from version 1.08 to 1.09.
+
+This upgrade is part of a larger change to use L<parent> rather than L<base>.
+
+=item *
+
+L<Hash::Util::FieldHash> has been upgraded from version 1.12 to 1.13.
+
+This upgrade is part of a larger change to use L<parent> rather than L<base>.
=item *
L<I18N::LangTags> has been upgraded from version 0.39 to 0.40.
Bosnian has now joined Croatian and Serbian in the lists of mutually
-intelligible Slavic languages. [perl #72594]
+intelligible Slavic languages. [perl #72594]
=item *
=item *
+L<IO::Socket> has been upgraded from version 1.36 to 1.37.
+
+The C<connect> method has been updated in the light of changes made in the
+assignment of sockets error codes to $! on Windows (see L</Incompatible
+Changes>).
+
+=item *
+
L<IPC::Open3> has been upgraded from version 1.15 to 1.16.
This upgrade is part of a larger change to preserve referential identity when
=item *
+L<JSON::PP> has been patched from version 2.27202 to 2.27202_01.
+
+A precedence issue has been fixed in the return value of a private subroutine.
+
+=item *
+
L<Locale::Codes> has been upgraded from version 3.26 to 3.27.
New codes have been added and the (deprecated) set of FIPS-10 country codes has
L<Math::BigInt> has been upgraded from version 1.9992 to 1.9993.
Cleaned up the L<Math::BigInt> and L<Math::BigFloat> documentation to be more
-consistent with other perl documentation. [perl #86686]
+consistent with other Perl documentation. [perl #86686]
-Added a bint() method for rounding towards zero. [perl #85296]
+Added a C<bint> method for rounding towards zero. [perl #85296]
=item *
=item *
-L<Module::CoreList> has been upgraded from version 2.97 to 2.98.
+L<Module::CoreList> has been upgraded from version 2.97 to 2.99.
The list of Perl versions covered has been updated.
+A function C<is_core> has been added, which returns true if the specified
+module was bundled with Perl. Optionally you can specify a minimum version of
+the module, and the specific version of Perl you're interested in (defaults to
+$^V, the running version of Perl).
+
=item *
L<Module::Load::Conditional> has been upgraded from version 0.54 to 0.58.
-C<requires> has been made more robust. [cpan #83728]
+C<requires> has been made more robust. [cpan #83728]
=item *
L<Module::Metadata> has been upgraded from version 1.000014 to 1.000018.
The module's DESCRIPTION has been re-worded regarding safety/security to
-satisfy CVE-2013-1437. Also, versions are now detainted if needed. [cpan
+satisfy CVE-2013-1437. Also, versions are now detainted if needed. [cpan
#88576]
=item *
=item *
-L<parent> has been upgraded from version 0.226 to 0.227.
+L<Opcode> has been upgraded from version 1.25 to 1.26.
+
+The new kvaslice and kvhslice operators have been added.
+
+=item *
+
+L<parent> has been upgraded from version 0.226 to 0.228.
No changes have been made to the installed code other than the version bump to
keep in sync with the latest CPAN release.
=item *
+L<Pod::Html> has been upgraded from version 1.20 to 1.21.
+
+This upgrade is part of a larger change to use L<parent> rather than L<base>.
+
+=item *
+
+L<POSIX> has been upgraded from version 1.34 to 1.35.
+
+The list of E* constants exported on Windows has been updated to reflect the
+changes made in the assignment of sockets error codes to $! (see
+L</Incompatible Changes>).
+
+=item *
+
L<re> has been upgraded from version 0.25 to 0.26.
-A function signature has been corrected in the XS implementation.
+This upgrade is part of a larger change to support 64-bit string lengths in the
+regular expression engine.
=item *
L<Socket> has been upgraded from version 2.011 to 2.012.
-Syntax errors when building on the WinCE platform have been fixed. [cpan #87389]
+Syntax errors when building on the WinCE platform have been fixed. [cpan
+#87389]
=item *
=item *
+L<Test::Simple> has been patched from version 0.98 to 0.98_06.
+
+A precedence issue has been fixed in the return value of a private subroutine
+in L<Test::Builder>.
+
+=item *
+
L<Time::Piece> has been upgraded from version 1.22 to 1.23.
Day of year parsing (like "%y%j") has been fixed.
L<XS::Typemap> has been upgraded from version 0.10 to 0.11.
+This upgrade is part of the change to remove the uninitialized warnings
+exemption for uninitialized values returned by XSUBs (see the L</Selected Bug
+Fixes> section).
+
=back
=head2 Removed Modules and Pragmata
=head2 New Documentation
-XXX Changes which create B<new> files in F<pod/> go here.
-
-=head3 L<XXX>
+=head3 L<perlrepository>
-XXX Description of the purpose of the new file here
+This document was removed (actually, renamed L<perlgit> and given a major
+overhaul) in Perl 5.13.10, causing Perl documentation websites to show the now
+out of date version in Perl 5.12 as the latest version. It has now been
+restored in stub form, directing readers to current information.
=head2 Changes to Existing Documentation
-XXX Changes which significantly change existing files in F<pod/> go here.
-However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
-section.
+=head3 L<perldata>
+
+=over 4
+
+=item *
+
+New sections have been added to document the new index/value array slice and
+key/value hash slice syntax.
-=head3 L<XXX>
+=back
+
+=head3 L<perldebguts>
=over 4
=item *
-XXX Description of the change here
+The C<&DB::goto> and C<&DB::lsub> debugger subroutines are now documented.
+[perl #77680]
+
+=back
+
+=head3 L<perlguts>
+
+=over 4
+
+=item *
+
+Numerous minor changes have been made to reflect changes made to the perl
+internals in this release.
+
+=back
+
+=head3 L<perlhack>
+
+=over 4
+
+=item *
+
+The L<SUPER QUICK PATCH GUIDE|perlhack/SUPER QUICK PATCH GUIDE> section has
+been updated.
+
+=back
+
+=head3 L<perlsub>
+
+=over 4
+
+=item *
+
+A list of subroutine names used by the perl implementation is now included.
+[perl #77680]
=back
=item *
-XXX L<message|perldiag/"message">
+L<delete argument is indexE<sol>value array slice, use array slice|perldiag/"delete argument is index/value array slice, use array slice">
+
+(F) You used index/value array slice syntax (C<%array[...]>) as the argument to
+C<delete>. You probably meant C<@array[...]> with an @ symbol instead.
+
+=item *
+
+L<delete argument is keyE<sol>value hash slice, use hash slice|perldiag/"delete argument is key/value hash slice, use hash slice">
+
+(F) You used key/value hash slice syntax (C<%hash{...}>) as the argument to
+C<delete>. You probably meant C<@hash{...}> with an @ symbol instead.
=back
L<Invalid \0 character in %s for %s: %s\0%s|perldiag/"Invalid \0 character in %s for %s: %s\0%s">
(W syscalls) Embedded \0 characters in pathnames or other system call arguments
-produce a warning as of 5.20. The parts after the \0 were formerly ignored by
+produce a warning as of 5.20. The parts after the \0 were formerly ignored by
system calls.
+=item *
+
+L<Possible precedence issue with control flow operator|perldiag/"Possible precedence issue with control flow operator">
+
+(W syntax) There is a possible problem with the mixing of a control flow
+operator (e.g. C<return>) and a low-precedence operator like C<or>. Consider:
+
+ sub { return $a or $b; }
+
+This is parsed as:
+
+ sub { (return $a) or $b; }
+
+Which is effectively just:
+
+ sub { return $a; }
+
+Either use parentheses or the high-precedence variant of the operator.
+
+Note this may be also triggered for constructs like:
+
+ sub { 1 if die; }
+
+=item *
+
+L<Scalar value %%s[%s] better written as $%s[%s]|perldiag/"Scalar value %%s[%s] better written as $%s[%s]">
+
+(W syntax) In scalar context, you've used an array index/value slice (indicated
+by %) to select a single element of an array. Generally it's better to ask for
+a scalar value (indicated by $). The difference is that C<$foo[&bar]> always
+behaves like a scalar, both in the value it returns and when evaluating its
+argument, while C<%foo[&bar]> provides a list context to its subscript, which
+can do weird things if you're expecting only one subscript. When called in
+list context, it also returns the index (what C<&bar> returns) in addition to
+the value.
+
+=item *
+
+L<Scalar value %%s{%s} better written as $%s{%s}|perldiag/"Scalar value %%s{%s} better written as $%s{%s}">
+
+(W syntax) In scalar context, you've used a hash key/value slice (indicated by
+%) to select a single element of a hash. Generally it's better to ask for a
+scalar value (indicated by $). The difference is that C<$foo{&bar}> always
+behaves like a scalar, both in the value it returns and when evaluating its
+argument, while C<@foo{&bar}> and provides a list context to its subscript,
+which can do weird things if you're expecting only one subscript. When called
+in list context, it also returns the key in addition to the value.
+
=back
=head2 Changes to Existing Diagnostics
=item *
-The "Unknown switch condition" error message has some slight changes.
-This error triggers when there is an unknown condition in a (?(foo))
-conditional; The error message used to read:
+The "Unknown switch condition" error message has some slight changes. This
+error triggers when there is an unknown condition in a C<(?(foo))> conditional.
+The error message used to read:
Unknown switch condition (?(%s in regex;
-But what %s could be was mostly up to luck; For (?(foobar)), you
-might've seen "fo" or "f". For Unicode characters, you'd generally
-get a corrupted string.
-The message was changed to read:
+But what %s could be was mostly up to luck. For C<(?(foobar))>, you might have
+seen "fo" or "f". For Unicode characters, you would generally get a corrupted
+string. The message has been changed to read:
Unknown switch condition (?(...)) in regex;
-And additionally, the '<-- HERE' marker in the error will now point
-to the correct spot in the regex.
+Additionally, the C<'E<lt>-- HERE'> marker in the error will now point to the
+correct spot in the regex.
+
+=item *
+
+The "%s "\x%X" does not map to Unicode" warning is now correctly listed as a
+severe warning rather than as a fatal error.
=back
=item *
-L<find2perl> now handles C<?> wildcards correctly. [perl #113054]
+L<find2perl> now handles C<?> wildcards correctly. [perl #113054]
=back
=item *
+A bug that was fixed in Perl 5.15.4 is now tested by the new test script
+F<t/io/eintr_print.t>. [perl #119097]
+
+=item *
+
+The new test scripts F<t/op/kvaslice.t> and F<t/op/kvhslice.t> test the new
+index/value array slice and key/value hash slice syntax respectively.
+
+=item *
+
Various cases of C<die>, C<last>, C<goto> and C<exit> triggering C<DESTROY> are
now tested by the new test script F<t/op/rt119311.t>.
=item *
-The new test script F<t/win32/signal.t> tests that C<$!> and C<$^E> are now
-preserved across signal handlers by the Win32 signal emulation code.
+The new test script F<t/op/waitpid.t> tests the fix for [perl #85228] (see
+L</Selected Bug Fixes>).
+
+=item *
+
+The latest copyright years in the top-level F<README> file and the B<perl -v>
+output are now tested as matching each other by the new test script
+F<t/porting/copyright.t>
+
+=item *
+
+The new test script F<t/win32/signal.t> tests that $! and $^E are now preserved
+across signal handlers by the Win32 signal emulation code.
=item *
=head2 Discontinued Platforms
-XXX List any platforms that this version of perl no longer compiles on.
-
-Configure hints and conditional code for several very old platforms
-has been removed. We have not received reports for these in many years,
-typically not since perl-5.6.0.
+Configure hints and conditional code for several very old platforms has been
+removed. We have not received reports for these in many years, typically not
+since Perl 5.6.0.
=over 4
=item AT&T 3b1
-Configure support for the 3b1, also known as the AT&T Unix PC (and the
-similar AT&T 7300), has been removed.
+Configure support for the 3b1, also known as the AT&T Unix PC (and the similar
+AT&T 7300), has been removed.
=back
=over 4
+=item VMS
+
+The C<PERL_ENV_TABLES> feature to control the population of %ENV at perl
+start-up was broken in Perl 5.16.0 but has now been fixed.
+
+=item Win32
+
+C<rename> and C<link> on Win32 now set $! to ENOSPC and EDQUOT when
+appropriate. [perl #119857]
+
=item WinCE
-The building of XS modules has largely been restored. Several still cannot
+Perl now builds again on WinCE, following locale-related breakage (WinCE has
+non-existent locale support) introduced around 5.19.1. [perl #119443]
+
+The building of XS modules has largely been restored. Several still cannot
(yet) be built but it is now possible to build Perl on WinCE with only a couple
of further patches (to L<Socket> and L<ExtUtils::MakeMaker>), hopefully to be
incorporated soon.
+=item GNU/Hurd
+
+The BSD compatibility library C<libbsd> is no longer required for builds.
+
=back
=head1 Internal Changes
=item *
-The internal representation has changed for the match variables C<$1>, C<$2>
-I<etc.>, C<$`>, C<$&>, C<$'>, C<${^PREMATCH}>, C<${^MATCH}> and
-C<${^POSTMATCH>. It uses slightly less memory, avoids string comparisons
-and numeric conversions during lookup, and uses 23 fewer lines of C. This
-change should not affect any external code.
+The internal representation has changed for the match variables $1, $2 etc.,
+$`, $&, $', ${^PREMATCH}, ${^MATCH} and ${^POSTMATCH}. It uses slightly less
+memory, avoids string comparisons and numeric conversions during lookup, and
+uses 23 fewer lines of C. This change should not affect any external code.
=item *
Arrays now use NULL internally to represent unused slots, instead of
-C<&PL_sv_undef>. C<&PL_sv_undef> is no longer treated as a special value,
-so C<av_store(av, 0, &PL_sv_undef)> will cause element 0 of that array to
-hold a read-only undefined scalar. C<$array[0] = anything> will croak and
+&PL_sv_undef. &PL_sv_undef is no longer treated as a special value, so
+av_store(av, 0, &PL_sv_undef) will cause element 0 of that array to hold a
+read-only undefined scalar. C<$array[0] = anything> will croak and
C<\$array[0]> will compare equal to C<\undef>.
+=item *
+
+The SV returned by HeSVKEY_force() now correctly reflects the UTF8ness
+of the underlying hash key when that key is not stored as a SV. [perl
+#79074]
+
+=item *
+
+Certain rarely used functions and macros available to XS code are now, or are
+planned to be, deprecated. These are:
+C<utf8n_to_uvuni> (use C<utf8_to_uvchr_buf> instead),
+C<utf8_to_uni_buf> (use C<utf8_to_uvchr_buf> instead),
+C<valid_utf8_to_uvuni> (use C<utf8_to_uvchr_buf> instead),
+C<uvuni_to_utf8> (use C<uvchr_to_utf8> instead),
+C<NATIVE_TO_NEED> (this did not work properly anyway),
+and C<ASCII_TO_NEED> (this did not work properly anyway).
+
+Starting in this release, almost never does application code need to
+distinguish between the platform's character set and Latin1, on which the
+lowest 256 characters of Unicode are based.
+
=back
=head1 Selected Bug Fixes
=item *
-The value of C<$^E> is now saved across signal handlers on Win32. [perl #85104]
+The value of $^E is now saved across signal handlers on Windows. [perl #85104]
=item *
-A lexical filehandle (as in C<open my $fh...>) is usually given a name
-based on the current package and the name of the variable; e.g.,
-"main::$fh". Under recursion, the filehandle was losing the "$fh" part of
-the name. This has been fixed.
+A lexical filehandle (as in C<open my $fh...>) is usually given a name based on
+the current package and the name of the variable, e.g. "main::$fh". Under
+recursion, the filehandle was losing the "$fh" part of the name. This has been
+fixed.
=item *
-Perl 5.19.3 accidentally extended the previous bug to all closures, even
-when not called recursively; i.e., lexical handles in closure would always
-be called "main::" or "MyPackage::" etc. This has been fixed.
+Perl 5.19.3 accidentally extended the previous bug to all closures, even when
+not called recursively, i.e. lexical handles in closure would always be called
+"main::" or "MyPackage::" etc. This has been fixed.
=item *
-Uninitialized values returned by XSUBs are no longer exempt from
-uninitialized warnings. [perl #118693]
+Uninitialized values returned by XSUBs are no longer exempt from uninitialized
+warnings. [perl #118693]
=item *
-C<elsif ("")> no longer erroneous produces a warning about void context.
+C<elsif ("")> no longer erroneously produces a warning about void context.
[perl #118753]
=item *
-Passing C<undef> to a subroutine now causes @_ to contain the same read-only undefined scalar that C<undef> returns. Furthermore, C<exists $_[0]> will now return true if C<undef> was the first argument.
-[perl #7508, #109726].
+Passing C<undef> to a subroutine now causes @_ to contain the same read-only
+undefined scalar that C<undef> returns. Furthermore, C<exists $_[0]> will now
+return true if C<undef> was the first argument. [perl #7508, #109726]
=item *
-Passing a nonexistent array element to a subroutine does not usually
-autovivify it unless the subroutine modifies its argument. This did not
-work correctly with negative indices and with nonexistent elements within
-the array. The element would be vivified immediately. The delayed
-vivification has been extended to work with those. [perl #118691]
+Passing a nonexistent array element to a subroutine does not usually autovivify
+it unless the subroutine modifies its argument. This did not work correctly
+with negative indices and with nonexistent elements within the array. The
+element would be vivified immediately. The delayed vivification has been
+extended to work with those. [perl #118691]
=item *
-Assigning references or globs to the scalar returned by C<$#foo> after the
-@foo array has been freed no longer causes assertion failures on debugging
-builds and memory leaks on regular builds.
+Assigning references or globs to the scalar returned by $#foo after the @foo
+array has been freed no longer causes assertion failures on debugging builds
+and memory leaks on regular builds.
=item *
-Perl 5.19.2 threw line numbers off after some cases of line breaks
-following keywords, such as
+Perl 5.19.2 threw line numbers off after some cases of line breaks following
+keywords, such as
1 unless
1;
=item *
-On 64-bit platforms, large ranges like 1..1000000000000 no longer crash,
-but eat up all your memory instead. [perl #119161]
+On 64-bit platforms, large ranges like 1..1000000000000 no longer crash, but
+eat up all your memory instead. [perl #119161]
+
+=item *
+
+C<__DATA__> now puts the C<DATA> handle in the right package, even if the
+current package has been renamed through glob assignment.
+
+=item *
+
+The string position set by C<pos> could shift if the string changed
+representation internally to or from utf8. This could happen, e.g., with
+references to objects with string overloading.
+
+=item *
+
+Taking references to the return values of two C<pos> calls with the same
+argument, and then assigning a reference to one and C<undef> to the other,
+could result in assertion failures or memory leaks.
+
+=item *
+
+Elements of @- and @+ now update correctly when they refer to nonexistent
+captures. Previously, a referenced element (C<$ref = \$-[1]>) could refer to
+the wrong match after subsequent matches.
+
+=item *
+
+When C<die>, C<last>, C<next>, C<redo>, C<goto> and C<exit> unwind the scope,
+it is possible for C<DESTROY> recursively to call a subroutine or format that
+is currently being exited. It that case, sometimes the lexical variables
+inside the sub would start out having values from the outer call, instead of
+being undefined as they should. This has been fixed. [perl #119311]
+
+=item *
+
+${^MPEN} is no longer treated as a synonym for ${^MATCH}.
+
+=item *
+
+Perl now tries a little harder to return the correct line number in
+C<(caller)[2]>. [perl #115768]
+
+=item *
+
+Line numbers inside multiline quote-like operators are now reported correctly.
+[perl #3643]
+
+=item *
+
+C<#line> directives inside code embedded in quote-like operators are now
+respected.
+
+=item *
+
+Line numbers are now correct inside the second here-doc when two here-doc
+markers occur on the same line.
+
+=item *
+
+Starting with Perl 5.12, line numbers were off by one if the B<-d> switch was
+used on the #! line. Now they are correct.
+
+=item *
+
+Perl 5.19.2 inadvertently stopped some lines of code from being available to
+the debugger if C<=E<gt>> occurred at the beginning of a line and the previous
+line ended with a keyword. This is now fixed.
+
+=item *
+
+Perl 5.19.2 allowed the PERL5DB environment variable to contain multiple lines
+of code, but those lines were not made available to the debugger. Now they are
+all stuffed into line number 0, accessible via C<$dbline[0]> in the debugger.
+
+=item *
+
+An optimisation in Perl 5.18 made incorrect assumptions causing a bad
+interaction with the L<Devel::CallParser> CPAN module. If the module was
+loaded then lexical variables declared in separate statements following a
+C<my(...)> list might fail to be cleared on scope exit.
+
+=item *
+
+C<&xsub> and C<goto &xsub> calls now allow the called subroutine to autovivify
+elements of @_.
+
+=item *
+
+C<&xsub> and C<goto &xsub> no longer crash if *_ has been undefined and has no
+ARRAY entry (i.e. @_ does not exist).
+
+=item *
+
+C<&xsub> and C<goto &xsub> now work with tied @_.
+
+=item *
+
+Overlong identifiers no longer cause a buffer overflow (and a crash). They
+started doing so in Perl 5.18.
+
+=item *
+
+The warning "Scalar value @hash{foo} better written as $hash{foo}" now produces
+far fewer false positives. In particular, C<@hash{+function_returning_a_list}>
+and C<@hash{ qw "foo bar baz" }> no longer warn. The same applies to array
+slices. [perl #28380, #114024]
+
+=item *
+
+C<$! = EINVAL; waitpid(0, WNOHANG);> no longer goes into an internal infinite
+loop. [perl #85228]
+
+=item *
+
+Perl 5.19.3 accidentally caused C<\(1+2)> to return a reference to the same
+mutable scalar each time, so that modifications affect future evaluations.
+This has been fixed. [perl #119501]
=back
https://perl5.git.perl.org / perl5.git / blobdiff