+=for todo
+b47a847f62 win32/win32sck.c: dont close() a freed socket os handle
+35e037e846 Commit 1735f6f started to escape all...
+ff4a442c79 [perl #75156] fix the return value and bits for removing a...
+9b4bdfd44e fix chop formats with non PV vars
+
=encoding utf8
=head1 NAME
[ List each enhancement as a =head2 entry ]
+=head2 $a and $b warnings exemption
+
+The special variables $a and $b, used in C<sort>, are now exempt from "used
+once" warnings, even where C<sort> is not used. This makes it easier for
+CPAN modules to provide functions using $a and $b for similar purposes.
+[perl #120462]
+
=head1 Security
XXX Any security-related notices go here. In particular, any security
=item *
-XXX
+Constant hash key lookups (C<$hash{key}> as opposed to C<$hash{$key}>) have
+long had the internal hash value computed at compile time, to speed up
+lookup. This optimisation has only now been applied to hash slices as
+well.
=back
=item *
+L<B> has been upgraded from version 1.46 to 1.47.
+
+C<< B::PMOP->precomp >> now preserves the internal UTF8 flag correctly, so
+chr 256 remains chr 256, instead of turning into "\xc4\x80". This allows
+L<B::Deparse> to deparse Unicode regular expression correctly.
+[perl #120182]
+
+C<< B::HV->ARRAY >> now preserves the UTF8 flag on returned hash keys.
+[perl #120535]
+
+=item *
+
+L<B::Concise> has been upgraded from version 0.99 to 0.991.
+
+B<-debug> output now includes C<op_other> pointers.
+
+=item *
+
+L<B::Deparse> has been upgraded from version 1.23 to 1.24.
+
+C<s//\(3)/e> is now deparsed in a way that does not issue warnings when
+parsed again. [perl #119807]
+
+C<glob(my $x)> is now deparsed correctly, rather than as C<< <my $x> >> or
+similar.
+
+C<CORE::glob> is now deparsed correctly with the CORE:: prefix when there
+is a subroutine named "glob".
+
+=item *
+
L<Module::CoreList> has been upgraded from version 3.00 to 3.01.
The list of Perl versions covered has been updated.
+=item *
+
+L<PerlIO::scalar> has been upgraded from version 0.17 to 0.18.
+
+A bug fix in 0.17 caused references to be stringified as soon as a handle
+to it was opened, even if it was opened only for reading. It also croaked
+on read-only references. This has been fixed. [perl #119529]
+
+=item *
+
+L<Tie::StdHandle> has been upgraded from version 4.3 to 4.4.
+
+It no longer prints C<$\> twice. [perl #120202]
+
+It no longer ignores the offset passed to C<syswrite>.
+
=back
=head2 Removed Modules and Pragmata
=item *
-XXX Describe change here
+L<%%s[%s] in scalar context better written as $%s[%s]|perldiag/"%%s[%s] in scalar context better written as $%s[%s]">:
+
+This warning now occurs for any C<%array[$index]> or C<%hash{key}> known to
+be in scalar context at compile time. Previously it was worded "Scalar
+value %%s[%s] better written as $%s[%s]".
=back
=item *
-XXX
+F<ext/File-Find/t/find.t> has been converted from manual C<print>
+statements to Test::More functions. Each test now has a description.
+[perl #120503]
=back
=head1 Platform Support
-XXX Any changes to platform support should be listed in the sections below.
-
-[ Within the sections, list each platform as a =item entry with specific
-changes as paragraphs below it. ]
-
=head2 New Platforms
-XXX List any platforms that this version of perl compiles on, that previous
-versions did not. These will either be enabled by new files in the F<hints/>
-directories, or new subdirectories and F<README> files at the top level of the
-source tree.
-
=over 4
-=item XXX-some-platform
+=item Synology
-XXX
+Synology ships its NAS boxes with a lean Linux distribution (DSM) on relative
+cheap CPU's (like the Marvell Kirkwood mv6282 - ARMv5tel or Freescale QorIQ
+P1022 ppc - e500v2) not meant for workstations or development. These boxes
+should build now. The basic problems are the non-standard location for tools.
=back
=item *
-XXX
+Compiling with C<-Accflags=-PERL_BOOL_AS_CHAR> now allows C99 and C++
+compilers to emulate the aliasing of C<bool> to C<char> that perl does for
+C89 compilers. [perl #120314]
=back
=item *
-XXX
+Perl 5.18.0 accidentally disallowed C<-bareword> under C<use strict> and
+C<use integer>. This has been fixed. [perl #120288]
+
+=item *
+
+C<-a> at the start of a line (or a hyphen with any single letter that is
+not a filetest operator) no longer produces an erroneous 'Use of "-a"
+without parentheses is ambiguous' warning. [perl #120288]
+
+=item *
+
+Lvalue context is now properly propagated into bare blocks and C<if> and
+C<else> blocks in lvalue subroutines. Previously, arrays and hashes would
+sometimes incorrectly be flattened when returned in lvalue list context, or
+"Bizarre copy" errors could occur. [perl #119797]
+
+=item *
+
+Lvalue context is now propagated to the branches of C<||> and C<&&> (and
+their alphabetic equivalents, C<or> and C<and>). This means
+C<foreach (pos $x || pos $y) {...}> now allows C<pos> to be modified
+through $_.
+
+=item *
+
+C<*DB::DB = sub {} if 0> no longer stops Perl's debugging mode from finding
+C<DB::DB> subs declared thereafter.
+
+=item *
+
+C<stat> and C<readline> remember the last handle used; the former
+for the special C<_> filehandle, the latter for C<${^LAST_FH}>.
+C<eval "*foo if 0"> where *foo was the last handle passed to C<stat>
+or C<readline> could cause that handle to be forgotten if the
+handle were not opened yet. This has been fixed.
+
+=item *
+
+Various cases of C<delete $::{a}>, C<delete $::{ENV}> etc. causing a crash
+have been fixed. [perl #54044]
+
+=item *
+
+Assigning another typeglob to C<*^R> no longer makes the regular expression
+engine crash.
+
+=item *
+
+C<%{'_<...'}> hashes now set breakpoints on the corresponding C<@{'_<...'}>
+rather than whichever array C<@DB::dbline> is aliased to. [perl #119799]
+
+=item *
+
+Setting C<$!> to EACCESS before calling C<require> could affect
+C<require>'s behaviour. This has been fixed.
+
+=item *
+
+The "Can't use \1 to mean $1 in expression" warning message now only occurs
+on the right-hand (replacement) part of a substitution. Formerly it could
+happen in code embedded in the left-hand side, or in any other quote-like
+operator.
+
+=item *
+
+The C<\N> regular expression escape, when used without the curly braces (to
+mean C<[^\n]>), was ignoring a following C<*> if followed by whitespace
+under /x. It had been this way since C<\N> to mean C<[^\n]> was introduced
+in 5.12.0.
+
+=item *
+
+Blessing into a reference (C<bless $thisref, $thatref>) has long been
+disallowed, but magical scalars for the second like C<$/> and those tied
+were exempt. They no longer are. [perl #119809]
+
+=item *
+
+Blessing into a reference was accidentally allowed in 5.18 if the class
+argument were a blessed reference with stale method caches (i.e., whose
+class had had subs defined since the last method call). They are
+disallowed once more, as in 5.16.
+
+=item *
+
+An undefined lexical sub used as an inherited method no longer crashes.
+
+=item *
+
+C<< $x->{key} >> where $x was declared as C<my Class $x> no longer crashes
+if a Class::FIELDS subroutine stub has been declared.
+
+=item *
+
+C<@$obj{'key'}> and C<${$obj}{key}> used to be exempt from compile-time
+field checking ("No such class field"; see L<fields>) but no longer are.
+
+=item *
+
+That compile-time field checking also applies now to the C<%$obj{'key'}>
+syntax, added recently in Perl 5.19.4.
+
+=item *
+
+A nonexistent array element with a large index passed to a subroutine that
+ties the array and then tries to access the element no longer results in a
+crash.
+
+=item *
+
+Declaring a subroutine stub named NEGATIVE_INDICES no longer makes negative
+array indices crash when the current package is a tied array class.
+
+=item *
+
+Declaring a C<require>, C<glob>, or C<do> subroutine stub in the
+CORE::GLOBAL:: package no longer makes compilation of calls to the
+corresponding functions crash.
+
+=item *
+
+Aliasing CORE::GLOBAL:: functions to constants stopped working in Perl 5.10
+but has now been fixed.
+
+=item *
+
+When C<`...`> or C<qx/.../> calls a C<readpipe> override, double-quotish
+interpolation now happens, as is the case when there is no override.
+Previously, the presence of an override would make these quote-like
+operators act like C<q{}>, suppressing interpolation. [perl #115330]
+
+=item *
+
+C<<<`...`> here-docs (with backticks as the delimiters) now call
+C<readpipe> overrides. [perl #119827]
+
+=item *
+
+The presence of a lexical sub named "CORE" no longer stops the CORE::
+prefix from working.
+
+=item *
+
+C<&CORE::exit()> and C<&CORE::die()> now respect L<vmsish> hints.
+
+=item *
+
+Undefining a glob that triggers a DESTROY method that undefines the same
+glob is now safe. It used to produce "Attempt to free unreferenced glob
+pointer" warnings and leak memory.
+
+=item *
+
+If subroutine redefinition (C<eval 'sub foo{}'> or C<newXS> for XS code)
+triggers a DESTROY method on the sub that is being redefined, and that
+method assigns a subroutine to the same slot (C<*foo = sub {}>), C<$_[0]>
+is no longer left pointing to a freed scalar. Now DESTROY is delayed until
+the new subroutine has been installed.
+
+=item *
+
+C<s///>, C<tr///> and C<y///> now work when a wide character is used as the
+delimiter. [perl #120463]
=back
=item *
-XXX
+C<do CORE()> used to call a sub named "CORE" and treat its return value as
+a file name to execute. A bug fix inadvertently caused it to be
+interpreted as the deprecated "do-SUB" construct. (Yes, C<do
+I<bareword>()> is inconsistent.) This will likely be changed back.
=back
https://perl5.git.perl.org / perl5.git / blobdiff