=head1 NAME
-perldelta - what is new for perl v5.21.3
+perldelta - what is new for perl v5.21.4
=head1 DESCRIPTION
-This document describes differences between the 5.21.2 release and the 5.21.3
+This document describes differences between the 5.21.3 release and the 5.21.4
release.
-If you are upgrading from an earlier release such as 5.21.1, first read
-L<perl5212delta>, which describes differences between 5.21.1 and 5.21.2.
+If you are upgrading from an earlier release such as 5.21.2, first read
+L<perl5213delta>, which describes differences between 5.21.2 and 5.21.3.
=head1 Core Enhancements
-=head2 C<defined(@array = LIST)> is no longer fatal
+=head2 Infinity and NaN (not-a-number) handling improved
-In 5.21.1, C<defined(@array)> was made fatal. This has been relaxed
-to not die if the argument is assigning to an array.
+Floating point values are able to hold the special values infinity (also
+-infinity), and NaN (not-a-number). Now we more robustly recognize and
+propagate the value in computations, and on output normalize them to C<Inf> and
+C<NaN>.
-=head2 Floating point handling and parsing has been improved
+See also the L<POSIX> enhancements.
-Parsing and printing of floating point values has been improved.
-XXX what in addition to hexadecimal floats? if nothing, change the head2.
+=head1 Incompatible Changes
-As a completely new feature, hexadecimal floating point literals
-(like 0x1.23p-4) are now supported, and they can be output with
-C<printf %a>.
+=head2 Changes to the C<*> prototype
-=head1 Security
+The C<*> character in a subroutine's prototype used to allow barewords to take
+precedence over most, but not all subroutines. It was never consistent and
+exhibited buggy behaviour.
-=head2 The L<Safe> module could allow outside packages to be replaced
+Now it has been changed, so subroutines always take precedence over barewords,
+which brings it into conformity with similarly prototyped built-in functions:
-Critical bugfix: outside packages could be replaced. L<Safe> has
-been patched to 2.38 to address this.
+ sub splat($) { ... }
+ sub foo { ... }
+ splat(foo); # now always splat(foo())
+ splat(bar); # still splat('bar') as before
+ close(foo); # close(foo())
+ close(bar); # close('bar')
-=head1 Incompatible Changes
+=head1 Performance Enhancements
+
+=over 4
+
+=item *
+
+Subroutines with an empty prototype and bodies containing just C<undef> are now
+eligible for inlining.
+L<[perl #122728]|https://rt.perl.org/Ticket/Display.html?id=122728>
-=head2 S<C<use UNIVERSAL '...'>> is now a fatal error
+=item *
+
+Subroutines in packages no longer need to carry typeglobs around with them.
+Declaring a subroutine will now put a simple sub reference in the stash if
+possible, saving memory. The typeglobs still notionally exist, so accessing
+them will cause the subroutine reference to be upgraded to a typeglob. This
+optimization does not currently apply to XSUBs or exported subroutines, and
+method calls will undo it, since they cache things in typeglobs.
+L<[perl #120441]|https://rt.perl.org/Ticket/Display.html?id=120441>
-Importing functions from C<UNIVERSAL> has been deprecated since v5.12, and
-is now a fatal error. S<C<"use UNIVERSAL">> without any arguments is still
-allowed.
+=back
=head1 Modules and Pragmata
+=head2 New Modules and Pragmata
+
+=over 4
+
+=item *
+
+L<B::Op_private> provides detailed information about the flags used in the
+C<op_private> field of perl opcodes.
+
+=back
+
=head2 Updated Modules and Pragmata
=over 4
=item *
-L<B::Debug> has been upgraded from version 1.19 to 1.21.
+L<Archive::Tar> has been upgraded from version 2.00 to 2.02.
+
+Tests can now be run in parallel.
+
+=item *
+
+L<Attribute::Handlers> has been upgraded from version 0.96 to 0.97.
+
+Internal changes to account for the fact that subroutines in packages no longer
+need to carry typeglobs around with them (see under L</Performance
+Enhancements>).
+
+=item *
+
+L<attributes> has been upgraded from version 0.22 to 0.23.
+
+The usage of C<memEQs> in the XS has been corrected.
+L<[perl #122701]|https://rt.perl.org/Ticket/Display.html?id=122701>
+
+=item *
+
+L<B> has been upgraded from version 1.50 to 1.51.
+
+It provides a new C<B::safename> function, based on the existing
+C<< B::GV->SAFENAME >>, that converts "\cOPEN" to "^OPEN".
=item *
-L<Config::Perl::V> has been upgraded from version 0.20 to 0.22.
+L<B::Concise> has been upgraded from version 0.992 to 0.993.
+
+Internal changes to account for the fact that the defines and labels for the
+flags in the C<op_private> field of OPs are now auto-generated (see under
+L</Internal Changes>).
=item *
-L<CPAN::Meta> has been upgraded from version 2.141520 to 2.142060.
+L<B::Deparse> has been upgraded from version 1.27 to 1.28.
+
+It now deparses C<our(I<LIST>)> and typed lexical (C<my Dog $spot>) correctly.
=item *
-L<CPAN::Meta::Requirements> has been upgraded from version 2.125 to 2.126.
+L<bignum> has been upgraded from version 0.37 to 0.38.
+
+An C<eval BLOCK> rather than an C<eval EXPR> is now used to see if we can find
+Math::BigInt::Lite.
=item *
-L<ExtUtils::Manifest> has been upgraded from version 1.64 to 1.65.
+L<constant> has been upgraded from version 1.31 to 1.32.
+
+It now accepts fully-qualified constant names, allowing constants to be defined
+in packages other than the caller.
=item *
-L<HTTP::Tiny> has been upgraded from version 0.043 to 0.047.
+L<CPAN::Meta::Requirements> has been upgraded from version 2.126 to 2.128.
+
+Works around limitations in version::vpp detecting v-string magic and adds
+support for forthcoming L<ExtUtils::MakeMaker> bootstrap F<version.pm> for
+Perls older than 5.10.0.
=item *
-L<perl5db.pl> has been upgraded from version 1.45 to 1.46.
+L<Data::Dumper> has been upgraded from version 2.152 to 2.154.
+
+Fixes CVE-2014-4330 by adding a configuration variable/option to limit
+recursion when dumping deep data structures.
=item *
-L<POSIX> has been upgraded from version 1.41 to 1.42.
+L<experimental> has been upgraded from version 0.008 to 0.010.
+
+Hardcodes features for Perls older than 5.15.7.
=item *
-L<Safe> has been upgraded from version 2.37 to 2.38.
+L<ExtUtils::CBuilder> has been upgraded from version 0.280217 to 0.280219.
+
+Fixes a regression on Android.
+L<[perl #122675]|https://rt.perl.org/Ticket/Display.html?id=122675>
=item *
-L<Socket> has been upgraded from version 2.014 to 2.015.
+L<ExtUtils::Install> has been upgraded from version 1.68 to 2.04.
-=back
+No changes to installed files other than version bumps.
-=head1 Documentation
+=item *
-=head2 Changes to Existing Documentation
+L<ExtUtils::Manifest> has been upgraded from version 1.65 to 1.68.
-=head3 L<perlexperiment>
+Fixes a bug with C<maniread()>'s handling of quoted filenames and improves
+C<manifind()> to follow symlinks.
+L<[perl #122415]|https://rt.perl.org/Ticket/Display.html?id=122415>
-=over 4
+=item *
+
+L<File::Find> has been upgraded from version 1.27 to 1.28.
+
+C<find()> and C<finddepth()> will now warn if passed inappropriate or
+misspelled options.
+
+=item *
+
+L<Getopt::Std> has been upgraded from version 1.10 to 1.11.
+
+Corrects a typo in the documentation.
+
+=item *
+
+L<HTTP::Tiny> has been upgraded from version 0.047 to 0.049.
+
+C<keep_alive> is now fork-safe and thread-safe.
+
+=item *
+
+L<IO> has been upgraded from version 1.33 to 1.34.
+
+The XS implementation has been fixed for the sake of older Perls.
+
+=item *
+
+L<IO::Socket::IP> has been upgraded from version 0.31 to 0.32.
+
+Implements Timeout for C<connect()>.
+L<[cpan #92075]|https://rt.cpan.org/Ticket/Display.html?id=92075>
+
+=item *
+
+L<Locale::Codes> has been upgraded from version 3.31 to 3.32.
+
+New codes have been added.
+
+=item *
+
+L<Math::BigInt> has been upgraded from version 1.9996 to 1.9997.
+
+The documentation now gives test examples using L<Test::More> rather than
+L<Test>.
+
+=item *
+
+L<Module::CoreList> has been upgraded from version 5.021003 to 5.20140915.
+
+Updated to cover the latest releases of Perl.
+
+=item *
+
+L<overload> has been upgraded from version 1.22 to 1.23.
+
+A redundant C<ref $sub> check has been removed.
+
+=item *
+
+PathTools has been upgraded from version 3.49 to 3.50.
+
+A warning from the B<gcc> compiler is now avoided when building the XS.
+
+=item *
+
+L<Pod::Perldoc> has been upgraded from version 3.23 to 3.24.
+
+Filehandles opened for reading or writing now have C<:encoding(UTF-8)> set.
+L<[cpan #98019]|https://rt.cpan.org/Ticket/Display.html?id=98019>
+
+=item *
+
+L<POSIX> has been upgraded from version 1.42 to 1.43.
+
+The C99 math functions and constants (for example acosh, isinf, isnan, round,
+trunc; M_E, M_SQRT2, M_PI) have been added.
+
+=item *
+
+Scalar-List-Utils has been upgraded from version 1.39 to 1.41.
+
+A new module, L<Sub::Util>, has been added, containing functions related to
+CODE refs, including C<subname> (inspired by Sub::Identity) and C<set_subname>
+(copied and renamed from Sub::Name).
+
+The use of C<GetMagic> in C<List::Util::reduce()> has also been fixed.
+L<[cpan #63211]|https://rt.cpan.org/Ticket/Display.html?id=63211>
+
+=item *
+
+L<Term::ReadLine> has been upgraded from version 1.14 to 1.15.
+
+Faster checks are now made first in some if-statements.
+
+=item *
+
+L<Test::Harness> has been upgraded from version 3.32 to 3.33.
+
+Various documentation fixes.
+
+=item *
+
+L<Test::Simple> has been upgraded from version 1.001003 to 1.001006.
+
+Various documentation fixes.
=item *
-Added reference to L<feature>.
+L<threads> has been upgraded from version 1.95 to 1.96.
+
+No changes to installed files other than version bumps.
+
+=item *
+
+L<Time::Piece> has been upgraded from version 1.27 to 1.29.
+
+When pretty printing negative Time::Seconds, the "minus" is no longer lost.
+
+=item *
+
+L<version> has been upgraded from version 0.9908 to 0.9909.
+
+Numerous changes. See the F<Changes> file in the CPAN distribution for
+details.
=back
-=head3 L<perlguts>
+=head1 Documentation
+
+=head2 Changes to Existing Documentation
+
+=head3 L<perlfunc>
=over 4
=item *
-Details on C level symbols and libperl.t added.
+Calling C<delete> or C<exists> on array values is now described as "strongly
+discouraged" rather than "deprecated".
=back
-=head3 L<perlhacktips>
+=head3 L<perlpolicy>
=over 4
=item *
-Recommended replacements for tmpfile, atoi, strtol, and strtoul added.
+The conditions for marking an experimental feature as non-experimental are now
+set out.
=back
-=head3 L<perlop>
+=head3 L<perlrecharclass>
=over 4
=item *
-ASCII v. EBCDIC clarifications added.
+The documentation of Bracketed Character Classes has been expanded to cover the
+improvements in C<qr/[\N{named sequence}]/> (see under L</Selected Bug Fixes>).
=back
-=head3 L<perlsec>
+=head3 L<perlsyn>
=over 4
=item *
-Comments added on algorithmic complexity and tied hashes.
+An ambiguity in the documentation of the Ellipsis statement has been corrected.
+L<[perl #122661]|https://rt.perl.org/Ticket/Display.html?id=122661>
=back
-=head3 L<perlvms>
+=head3 L<perlxs>
=over 4
=item *
-Updated documentation on environment and shell interaction in VMS.
+Added a discussion of locale issues in XS code.
=back
=head2 New Diagnostics
-=head3 New Errors
+=head3 New Warnings
=over 4
=item *
-L<Hexadecimal float: internal error|perldiag/"Hexadecimal float: internal error">
+L<Character in 'C' format overflow in pack|perldiag/"Character in 'C' format overflow in pack">
-(F) Something went horribly bad in hexadecimal float handling.
+(W pack) You tried converting an infinity or not-a-number to an unsigned
+character, which makes no sense. Perl behaved as if you tried to pack 0xFF.
=item *
-L<Hexadecimal float: unsupported long double format|perldiag/"Hexadecimal float: unsupported long double format">
+L<Character in 'c' format overflow in pack|perldiag/"Character in 'c' format overflow in pack">
-(F) You have configured Perl to use long doubles but
-the internals of the long double format are unknown,
-therefore the hexadecimal float output is impossible.
+(W pack) You tried converting an infinity or not-a-number to a signed
+character, which makes no sense. Perl behaved as if you tried to pack 0xFF.
-=back
+=item *
-=head3 New Warnings
+L<Invalid number (%f) in chr|perldiag/"Invalid number (%f) in chr">
-=over 4
+(W utf8) You passed an invalid number (like an infinity or not-a-number) to
+C<chr>. Those are not valid character numbers, so it returned the Unicode
+replacement character (U+FFFD).
-=item *
+=back
-L<Hexadecimal float: exponent overflow|perldiag/"Hexadecimal float: exponent overflow">
+=head2 Changes to Existing Diagnostics
-(W overflow) The hexadecimal floating point has larger exponent
-than the floating point supports.
+=over 4
=item *
-L<Hexadecimal float: exponent underflow|perldiag/"Hexadecimal float: exponent underflow">
+L<Global symbol "%s" requires explicit package name|perldiag/"Global symbol "%s" requires explicit package name (did you forget to declare "my %s"?)">
-(W overflow) The hexadecimal floating point has smaller exponent
-than the floating point supports.
+This message has had '(did you forget to declare "my %s"?)' appended to it, to
+make it more helpful to new Perl programmers.
+L<[perl #121638]|https://rt.perl.org/Ticket/Display.html?id=121638>
=item *
-L<Hexadecimal float: mantissa overflow|perldiag/"Hexadecimal float: mantissa overflow">
+L<\N{} in character class restricted to one character in regex; marked by S<<-- HERE> in mE<sol>%sE<sol>|perldiag/"\N{} in inverted character class or as a range end-point is restricted to one character in regex; marked by S<<-- HERE> in m/%s/">
-(W overflow) The hexadecimal floating point literal had more bits in
-the mantissa (the part between the 0x and the exponent, also known as
-the fraction or the significand) than the floating point supports.
+This message has had 'character class' changed to 'inverted character class or
+as a range end-point is' to reflect improvements in C<qr/[\N{named sequence}]/>
+(see under L</Selected Bug Fixes>).
=item *
-L<Hexadecimal float: precision loss|perldiag/"Hexadecimal float: precision loss">
+L<panic: frexp|perldiag/"panic: frexp: %f">
-(W overflow) The hexadecimal floating point had internally more
-digits than could be output. This can be caused by unsupported
-long double formats, or by 64-bit integers not being available
-(needed to retrieve the digits under some configurations).
+This message has had ': %f' appended to it, to show what the offending floating
+point number is.
=back
-=head2 Changes to Existing Diagnostics
+=head2 Diagnostic Removals
=over 4
=item *
-C<require> with no argument or undef used to warn about a Null filename; now
-it dies with C<Missing or undefined argument to require>.
+"Constant is not a FOO reference"
+
+Compile-time checking of constant dereferencing (e.g., C<< my_constant->() >>)
+has been removed, since it was not taking overloading into account.
+L<[perl #69456]|https://rt.perl.org/Ticket/Display.html?id=69456>
+L<[perl #122607]|https://rt.perl.org/Ticket/Display.html?id=122607>
+
+=item *
+
+"Ambiguous use of -foo resolved as -&foo()"
+
+There is actually no ambiguity here, and this impedes the use of negated
+constants; e.g., C<-Inf>.
=back
=head1 Configuration and Compilation
+For long doubles (to get more precision and range for floating point
+numbers) one can now use the GCC quadmath library which implements
+the quadruple precision floating point numbers in x86 and ia64 platforms.
+See INSTALL for details.
+
+=head1 Testing
+
=over 4
=item *
-MurmurHash64A and MurmurHash64B can now be configured as the internal hash
-function.
+A new test script, F<op/infnan.t>, has been added to test if Inf and NaN are
+working correctly. See L</Infinity and NaN (not-a-number) handling improved>.
-=back
+=item *
+
+A new test script, F<re/rt122747.t>, has been added to test that the fix for
+L<perl #122747|https://rt.perl.org/Ticket/Display.html?id=122747> is working.
-=head1 Platform Support
+=back
-=head2 Platform-Specific Notes
+=head1 Internal Changes
=over 4
-=item Android
+=item *
-Build support has been improved for cross-compiling in general and for
-Android in particular.
+C<save_re_context> no longer does anything and has been moved to F<mathoms.c>.
-=item Solaris
+=item *
-C<c99> options have been cleaned up, hints look for C<solstudio>
-as well as C<SUNWspro>, and support for native C<setenv> has been added.
+C<cv_name> is a new API function that can be passed a CV or GV. It returns an
+SV containing the name of the subroutine for use in diagnostics.
+L<[perl #116735]|https://rt.perl.org/Ticket/Display.html?id=116735>
+L<[perl #120441]|https://rt.perl.org/Ticket/Display.html?id=120441>
-=item VMS
+=item *
-C<finite>, C<finitel>, and C<isfinite> detection has been added to
-C<configure.com>, environment handling has had some minor changes, and
-a fix for legacy feature checking status.
+C<cv_set_call_checker_flags> is a new API function that works like
+C<cv_set_call_checker>, except that it allows the caller to specify whether the
+call checker requires a full GV for reporting the subroutine's name, or whether
+it could be passed a CV instead. Whatever value is passed will be acceptable
+to C<cv_name>. C<cv_set_call_checker> guarantees there will be a GV, but it
+may have to create one on the fly, which is inefficient.
+L<[perl #116735]|https://rt.perl.org/Ticket/Display.html?id=116735>
-=item Windows
+=item *
+
+C<CvGV> (which is not part of the API) is now a more complex macro, which may
+call a function and reify a GV. For those cases where is has been used as a
+boolean, C<CvHASGV> has been added, which will return true for CVs that
+notionally have GVs, but without reifying the GV. C<CvGV> also returns a GV
+now for lexical subs.
+L<[perl #120441]|https://rt.perl.org/Ticket/Display.html?id=120441>
-C<%I64d> is now being used instead of C<%lld> for MinGW.
+=item *
+
+Added L<perlapi/sync_locale>. Changing the program's locale should be avoided
+by XS code. Nevertheless, certain non-Perl libraries called from XS, such as
+C<Gtk> do so. When this happens, Perl needs to be told that the locale has
+changed. Use this function to do so, before returning to Perl.
+
+=item *
+
+The defines and labels for the flags in the C<op_private> field of OPs are now
+auto-generated from data in F<regen/op_private>. The noticeable effect of this
+is that some of the flag output of C<Concise> might differ slightly, and the
+flag output of C<perl -Dx> may differ considerably (they both use the same set
+of labels now). Also in debugging builds, there is a new assert in
+C<op_free()> that checks that the op doesn't have any unrecognized flags set in
+C<op_private>.
=back
-=head1 Internal Changes
+=head1 Selected Bug Fixes
=over 4
=item *
-Added L<perlapi/sync_locale>.
-Changing the program's locale should be avoided by XS code. Nevertheless,
-certain non-Perl libraries called from XS, such as C<Gtk> do so. When this
-happens, Perl needs to be told that the locale has changed. Use this function
-to do so, before returning to Perl.
+Constant dereferencing now works correctly for typeglob constants. Previously
+the glob was stringified and its name looked up. Now the glob itself is used.
+L<[perl #69456]|https://rt.perl.org/Ticket/Display.html?id=69456>
=item *
-Added L<perlapi/grok_atou> as a safer replacement for atoi and strtol.
+When parsing a funny character ($ @ % &) followed by braces, the parser no
+longer tries to guess whether it is a block or a hash constructor (causing a
+syntax error when it guesses the latter), since it can only be a block.
-=back
+=item *
-=head1 Selected Bug Fixes
+C<undef $reference> now frees the referent immediately, instead of hanging on
+to it until the next statement.
+L<[perl #122556]|https://rt.perl.org/Ticket/Display.html?id=122556>
-=over 4
+=item *
+
+Various cases where the name of a sub is used (autoload, overloading, error
+messages) used to crash for lexical subs, but have been fixed.
+
+=item *
+
+Bareword lookup now tries to avoid vivifying packages if it turns out the
+bareword is not going to be a subroutine name.
+
+=item *
+
+Compilation of anonymous constants (e.g., C<sub () { 3 }>) no longer deletes
+any subroutine named C<__ANON__> in the current package. Not only was
+C<*__ANON__{CODE}> cleared, but there was a memory leak, too. This bug goes
+back to Perl 5.8.0.
+
+=item *
+
+Stub declarations like C<sub f;> and C<sub f ();> no longer wipe out constants
+of the same name declared by C<use constant>. This bug was introduced in Perl
+5.10.0.
+
+=item *
+
+Under some conditions a warning raised in compilation of regular expression
+patterns could be displayed multiple times. This is now fixed.
+
+=item *
+
+C<qr/[\N{named sequence}]/> now works properly in many instances. Some names
+known to C<\N{...}> refer to a sequence of multiple characters, instead of the
+usual single character. Bracketed character classes generally only match
+single characters, but now special handling has been added so that they can
+match named sequences, but not if the class is inverted or the sequence is
+specified as the beginning or end of a range. In these cases, the only
+behavior change from before is a slight rewording of the fatal error message
+given when this class is part of a C<?[...])> construct. When the C<[...]>
+stands alone, the same non-fatal warning as before is raised, and only the
+first character in the sequence is used, again just as before.
+
+=item *
+
+Tainted constants evaluated at compile time no longer cause unrelated
+statements to become tainted.
+L<[perl #122669]|https://rt.perl.org/Ticket/Display.html?id=122669>
+
+=item *
+
+C<open $$fh, ...>, which vivifies a handle with a name like "main::_GEN_0", was
+not giving the handle the right reference count, so a double free could happen.
+
+=item *
+
+When deciding that a bareword was a method name, the parser would get confused
+if an "our" sub with the same name existed, and look up the method in the
+package of the "our" sub, instead of the package of the invocant.
+
+=item *
+
+The parser no longer gets confused by C<\U=> within a double-quoted string. It
+used to produce a syntax error, but now compiles it correctly.
+L<[perl #80368]|https://rt.perl.org/Ticket/Display.html?id=80368>
+
+=item *
+
+It has always been the intention for the C<-B> and C<-T> file test operators to
+treat UTF-8 encoded files as text. (L<perlfunc|perlfunc/-X FILEHANDLE> has
+been updated to say this.) Previously, it was possible for some files to be
+considered UTF-8 that actually weren't valid UTF-8. This is now fixed. The
+operators now work on EBCDIC platforms as well.
+
+=item *
+
+Under some conditions warning messages raised during regular expression pattern
+compilation were being output more than once. This has now been fixed.
+
+=item *
+
+A regression has been fixed that was introduced in Perl 5.20.0 (fixed in Perl
+5.20.1 as well as here) in which a UTF-8 encoded regular expression pattern
+that contains a single ASCII lowercase letter does not match its uppercase
+counterpart.
+L<[perl #122655]|https://rt.perl.org/Ticket/Display.html?id=122655>
+
+=item *
+
+Constant folding could incorrectly suppress warnings if lexical warnings (C<use
+warnings> or C<no warnings>) were not in effect and C<$^W> were false at
+compile time and true at run time.
+
+=item *
+
+Loading UTF8 tables during a regular expression match could cause assertion
+failures under debugging builds if the previous match used the very same
+regular expression.
+L<[perl #122747]|https://rt.perl.org/Ticket/Display.html?id=122747>
+
+=item *
+
+Thread cloning used to work incorrectly for lexical subs, possibly causing
+crashes or double frees on exit.
+
+=item *
+
+Since Perl 5.14.0, deleting C<$SomePackage::{__ANON__}> and then undefining an
+anonymous subroutine could corrupt things internally, resulting in
+L<Devel::Peek> crashing or L<B.pm|B> giving nonsensical data. This has been
+fixed.
+
+=item *
+
+C<(caller $n)[3]> now reports names of lexical subs, instead of treating them
+as "(unknown)".
+
+=item *
+
+C<sort subname LIST> now supports lexical subs for the comparison routine.
=item *
-Failing to compile C<use Foo> in an eval could leave a spurious
-C<BEGIN> subroutine definition, which would produce a "Subroutine
-BEGIN redefined" warning on the next use of C<use>, or other C<BEGIN>
-block. [perl #122107]
+Aliasing (e.g., via C<*x = *y>) could confuse list assignments that mention the
+two names for the same variable on either side, causing wrong values to be
+assigned.
+L<[perl #15667]|https://rt.perl.org/Ticket/Display.html?id=15667>
=item *
-C<method { BLOCK } ARGS> syntax now correctly parses the arguments if they
-begin with an opening brace. [perl #46947]
+Long here-doc terminators could cause a bad read on short lines of input. This
+has been fixed. It is doubtful that any crash could have occurred. This bug
+goes back to when here-docs were introduced in Perl 3.000 twenty-five years
+ago.
=item *
-External libraries and Perl may have different ideas of what the locale is.
-This is problematic when parsing version strings if the locale's numeric
-separator has been changed. Version parsing has been patched to ensure
-it handles the locales correctly. [perl #121930]
+An optimization in C<split> to treat C<split/^/> like C<split/^/m> had the
+unfortunate side-effect of also treating C<split/\A/> like C<split/^/m>, which
+it should not. This has been fixed. (Note, however, that C<split/^x/> does
+not behave like C<split/^x/m>, which is also considered to be a bug and will be
+fixed in a future version.)
+L<[perl #122761]|https://rt.perl.org/Ticket/Display.html?id=122761>
=item *
-A bug has been fixed where zero-length assertions and code blocks inside of a
-regex could cause C<pos> to see an incorrect value. [perl #122460]
+The little-known C<my Class $var> syntax (see L<fields> and L<attributes>)
+could get confused in the scope of C<use utf8> if C<Class> were a constant
+whose value contained Latin-1 characters.
=back
XXX Generate this with:
- perl Porting/acknowledgements.pl v5.21.2..HEAD
+ perl Porting/acknowledgements.pl v5.21.3..HEAD
=head1 Reporting Bugs
https://perl5.git.perl.org / perl5.git / blobdiff