=head2 Indented Here-documents
This adds a new modifier C<"~"> to here-docs that tells the parser
-that it should look for /^\s*$DELIM\n/ as the closing delimiter.
+that it should look for C</^\s*$DELIM\n/> as the closing delimiter.
These syntaxes are all supported:
S<C</[ ^ A-Z d-f p-x ]/xx>>. Details are at
L<perlre/E<sol>x and E<sol>xx>.
-=head2 @{^CAPTURE}, %{^CAPTURE}, and %{^CAPTURE_ALL}
+=head2 C<@{^CAPTURE}>, C<%{^CAPTURE}>, and C<%{^CAPTURE_ALL}>
C<@{^CAPTURE}> exposes the capture buffers of the last match as an
array. So C<$1> is C<${^CAPTURE}[0]>. This is a more efficient equivalent
to code like C<substr($matched_string,$-[0],$+[0]-$-[0])>, and you don't
have to keep track of the C<$matched_string> either. This variable has no
-single character equivalent. Note, like the other regex magic variables
-the contents of this variable is dynamic, if you wish to store it beyond
+single character equivalent. Note that, like the other regex magic variables,
+the contents of this variable is dynamic; if you wish to store it beyond
the lifetime of the match you must copy it to another array.
-C<%{^CAPTURE}> is the equivalent to C<%+> (I<i.e.>, named captures). Other than
+C<%{^CAPTURE}> is equivalent to C<%+> (I<i.e.>, named captures). Other than
being more self documenting there is no difference between the two forms.
-C<%{^CAPTURE_ALL}> is the equivalent to C<%-> (I<i.e.>, all named captures).
+C<%{^CAPTURE_ALL}> is equivalent to C<%-> (I<i.e.>, all named captures).
Other than being more self documenting there is no difference between the
two forms.
=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
+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-E<gt>(\%hash) >>). Previously they could only be
used when inlined.
=back
-=head2 "Escaped" colons and relative paths in PATH
+=head2 Escaped colons and relative paths in PATH
On Unix systems, Perl treats any relative paths in the PATH environment
variable as tainted when starting a new process. Previously, it was
allowing a backslash to escape a colon (unlike the OS), consequently
allowing relative paths to be considered safe if the PATH was set to
-something like C</\:.>. The check has been fixed to treat C<.> as tainted
+something like C</\:.>. The check has been fixed to treat C<"."> as tainted
in that example.
=head2 C<-Di> switch is now required for PerlIO debugging output
-Previously PerlIO debugging output would be sent to the file specified
+This is used for debugging of code within PerlIO to avoid recursive
+calls. Previously this 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.
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
+If perl is running setuid or the C<-T> switch was supplied,
C<PERLIO_DEBUG> is ignored and the debugging output is sent to
C<stderr> as for any other C<-D> switch.
But it is always correct to escape C<"{">, and the simple rule to
remember is to always do so.
+See L<Unescaped left brace in regex is illegal here|perldiag/Unescaped left brace in regex is illegal here in regex; marked by S<E<lt>-- HERE> in mE<sol>%sE<sol>>.
+
=head2 C<scalar(%hash)> return signature changed
The value returned for C<scalar(%hash)> will no longer show information about
(bar) = 3; # also an error
This makes the lvalue sub case consistent with C<(keys %hash) = ...> and
-C<(keys @_) = ...>, which are also errors. [perl #128187]
+C<(keys @_) = ...>, which are also errors.
+L<[perl #128187]|https://rt.perl.org/Public/Bug/Display.html?id=128187>
=head2 C<${^ENCODING}> has been removed
source filter such as L<Filter::Encoding> on CPAN or L<encoding>'s C<Filter>
option.
-=head2 POSIX::tmpnam() has been removed
+=head2 C<POSIX::tmpnam()> has been removed
The fundamentally unsafe C<tmpnam()> interface was deprecated in
Perl 5.22 and has now been removed. In its place you can use,
=item *
-Reduce cost of SvVALID().
+Reduce cost of C<SvVALID()>.
=item *
=item *
-Avoid sv_catpvn() in do_vop() when unneeded.
+Avoid C<sv_catpvn()> in C<do_vop()> when unneeded.
=item *
L<B::Xref> has been upgraded from version 1.05 to 1.06.
-It now uses 3-arg C<open()> instead of 2-arg C<open()>. [perl #130122]
+It now uses 3-arg C<open()> instead of 2-arg C<open()>.
+L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
=item *
The XS implementation now supports Deparse.
-This fixes a stack management bug. [perl #130487].
+This fixes a stack management bug.
+L<[perl #130487]|https://rt.perl.org/Public/Bug/Display.html?id=130487>.
=item *
L<Devel::SelfStubber> has been upgraded from version 1.05 to 1.06.
-It now uses 3-arg C<open()> instead of 2-arg C<open()>. [perl #130122]
+It now uses 3-arg C<open()> instead of 2-arg C<open()>.
+L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
=item *
L<diagnostics> has been upgraded from version 1.34 to 1.36.
-It now uses 3-arg C<open()> instead of 2-arg C<open()>. [perl #130122]
+It now uses 3-arg C<open()> instead of 2-arg C<open()>.
+L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
=item *
Document that using C<%!> loads Errno for you.
-It now uses 3-arg C<open()> instead of 2-arg C<open()>. [perl #130122]
+It now uses 3-arg C<open()> instead of 2-arg C<open()>.
+L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
=item *
L<ExtUtils::Embed> has been upgraded from version 1.33 to 1.34.
-It now uses 3-arg C<open()> instead of 2-arg C<open()>. [perl #130122]
+It now uses 3-arg C<open()> instead of 2-arg C<open()>.
+L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
=item *
L<Filter::Simple> has been upgraded from version 0.92 to 0.93.
It no longer treats C<no MyFilter> immediately following C<use MyFilter> as
-end-of-file. [perl #107726]
+end-of-file.
+L<[perl #107726]|https://rt.perl.org/Public/Bug/Display.html?id=107726>
=item *
L<I18N::LangTags> has been upgraded from version 0.40 to 0.42.
-It now uses 3-arg C<open()> instead of 2-arg C<open()>. [perl #130122]
+It now uses 3-arg C<open()> instead of 2-arg C<open()>.
+L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
=item *
L<lib> has been upgraded from version 0.63 to 0.64.
-It now uses 3-arg C<open()> instead of 2-arg C<open()>. [perl #130122]
+It now uses 3-arg C<open()> instead of 2-arg C<open()>.
+L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
=item *
L<OS2::Process> has been upgraded from version 1.11 to 1.12.
-It now uses 3-arg C<open()> instead of 2-arg C<open()>. [perl #130122]
+It now uses 3-arg C<open()> instead of 2-arg C<open()>.
+L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
=item *
L<perl5db.pl> has been upgraded from version 1.50 to 1.51.
-Ignore F</dev/tty> on non-Unix systems. [perl #113960]
+Ignore F</dev/tty> on non-Unix systems.
+L<[perl #113960]|https://rt.perl.org/Public/Bug/Display.html?id=113960>
=item *
=item *
L<POSIX> has been upgraded from version 1.65 to 1.76. This remedies several
-defects in making its symbols exportable. [perl #127821]
+defects in making its symbols exportable.
+L<[perl #127821]|https://rt.perl.org/Public/Bug/Display.html?id=127821>
The C<POSIX::tmpnam()> interface has been removed,
see L</"POSIX::tmpnam() has been removed">.
Trying to import POSIX subs that have no real implementations
L<Storable> has been upgraded from version 2.56 to 2.62.
-Fixes [perl #130098].
+Fixes
+L<[perl #130098]|https://rt.perl.org/Public/Bug/Display.html?id=130098>.
=item *
L<Term::ReadLine> has been upgraded from version 1.15 to 1.16.
-It now uses 3-arg C<open()> instead of 2-arg C<open()>. [perl #130122]
+It now uses 3-arg C<open()> instead of 2-arg C<open()>.
+L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
=item *
L<Test> has been upgraded from version 1.28 to 1.30.
-It now uses 3-arg C<open()> instead of 2-arg C<open()>. [perl #130122]
+It now uses 3-arg C<open()> instead of 2-arg C<open()>.
+L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
=item *
Compatibility with 5.8 has been restored.
-Fixes [perl #130469].
+Fixes
+L<[perl #130469]|https://rt.perl.org/Public/Bug/Display.html?id=130469>.
=item *
L<threads::shared> has been upgraded from version 1.51 to 1.56.
-This fixes [cpan #119529], [perl #130457]
+This fixes [cpan #119529],
+L<[perl #130457]|https://rt.perl.org/Public/Bug/Display.html?id=130457>
=item *
L<Unicode::UCD> has been upgraded from version 0.64 to 0.68.
-It now uses 3-arg C<open()> instead of 2-arg C<open()>. [perl #130122]
+It now uses 3-arg C<open()> instead of 2-arg C<open()>.
+L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
=item *
L<VMS::DCLsym> has been upgraded from version 1.06 to 1.08.
-It now uses 3-arg C<open()> instead of 2-arg C<open()>. [perl #130122]
+It now uses 3-arg C<open()> instead of 2-arg C<open()>.
+L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
=item *
Fixed a security hole in which binary files could be loaded from a path
outside of L<C<@INC>|perlvar/@INC>.
-It now uses 3-arg C<open()> instead of 2-arg C<open()>. [perl #130122]
+It now uses 3-arg C<open()> instead of 2-arg C<open()>.
+L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
=back
Clarified documentation of L<C<seek()>|perlfunc/seek>,
L<C<tell()>|perlfunc/tell> and L<C<sysseek()>|perlfunc/sysseek>
-regarding that positions are in bytes vs. characters.
+emphasizing that positions are in bytes and not characters.
L<[perl #128607]|https://rt.perl.org/Public/Bug/Display.html?id=128607>
=item *
=item *
-In L<C<split()>|perlfunc/split> added a caution about its use in Perls
-before v5.11, and noted that certain pattern modifiers are legal in it.
+In L<C<split()>|perlfunc/split> noted that certain pattern modifiers are
+legal, and added a caution about its use in Perls before v5.11,
=item *
=item *
-Clariy indentation rules, and note that we are migrating away from using
-tabs to indent, replacing them with sequences of SPACE characters.
+Clarify what editor tab stop rules to use, and note that we are
+migrating away from using tabs, replacing them with sequences of SPACE
+characters.
=back
=back
-=head3 L<perlmodinstall>
+=head3 L<perlmod>
=over 4
=item *
-Do not discourage manual @ISA.
+Do not discourage manual C<@ISA>.
=back
=item *
-Clarify behavior of single quote regexps.
+Note that white space must be used for quoting operators if the
+delimiter is a word character (I<i.e.>, matches C<\w>).
+
+=item *
+
+Clarify that in regular expression patterns delimited by single quotes,
+no variable interpolation is done.
=back
points, that in earlier versions were mentioned in sort of an appendix
on Version 8 regular expressions.
+=item *
+
Note that it is common to have the C</x> modifier and forget that this
means that C<"#"> has to be escaped.
no warnings "experimental::declared_refs";
use feature "declared_refs";
+See L</Declaring a reference to a variable>.
+
=item *
L<Version control conflict marker|perldiag/"Version control conflict marker">
L<%s: command not found|perldiag/"%s: command not found">
(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:
+instead of Perl. Check the C<#!> line, or manually feed your script into
+Perl yourself. The C<#!> line at the top of your file could look like:
#!/usr/bin/perl
L<%s: command not found: %s|perldiag/"%s: command not found: %s">
(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:
+instead of Perl. Check the C<#!> line, or manually feed your script into
+Perl yourself. The C<#!> line at the top of your file could look like:
#!/usr/bin/perl
use feature "declared_refs";
$fooref = my \$foo;
+See L</Declaring a reference to a variable>.
+
=item *
L<C<${^ENCODING}> is no longer supported. Its use will be fatal in Perl 5.28|perldiag/"${^ENCODING} is no longer supported. Its use will be fatal in Perl 5.28">
=item *
-Attribute "locked" is deprecated, and will disappear in Perl 5.28
-
-=item *
-
-Attribute "unique" is deprecated, and will disappear in Perl 5.28
-
-=item *
-
-Constants from lexical variables potentially modified elsewhere are
-deprecated. This will not be allowed in Perl 5.32
-
-=item *
-
-Deprecated use of my() in false conditional. This will be a fatal error
-in Perl 5.30
-
-=item *
-
-dump() better written as CORE::dump(). dump() will no longer be available
-in Perl 5.30
-
-=item *
-
-${^ENCODING} is no longer supported. Its use will be fatal in Perl 5.28
-
-=item *
-
-File::Glob::glob() will disappear in perl 5.30. Use File::Glob::bsd_glob()
-instead.
-
-=item *
-
-%s() is deprecated on :utf8 handles. This will be a fatal error in Perl 5.30
-
-=item *
-
-$* is no longer supported. Its use will be fatal in Perl 5.30
-
-=item *
-
-$* is no longer supported. Its use will be fatal in Perl 5.30
-
-=item *
-
-Opening dirhandle %s also as a file. This will be a fatal error in Perl 5.28
+Details as to the exact problem have been added to the diagnostics that
+occur when malformed UTF-8 is encountered when trying to convert to a
+code point.
=item *
-Opening filehandle %s also as a directory. This will be a fatal
-error in Perl 5.28
+L<Attribute "locked" is deprecated, and will disappear in Perl 5.28
+|perldiag/Attribute "locked" is deprecated, and will disappear in Perl 5.28>
=item *
-Setting $/ to a reference to %s as a form of slurp is deprecated,
-treating as undef. This will be fatal in Perl 5.28
+L<Attribute "unique" is deprecated, and will disappear in Perl 5.28
+|perldiag/Attribute "unique" is deprecated, and will disappear in Perl 5.28>
=item *
-Unescaped left brace in regex is deprecated here (and will be fatal
-in Perl 5.30), passed through in regex; marked by S<< E<lt>-- HERE >> in m/%s/
+L<Constants from lexical variables potentially modified elsewhere are deprecated. This will not be allowed in Perl 5.32
+|perldiag/Constants from lexical variables potentially modified elsewhere are deprecated. This will not be allowed in Perl 5.32>
=item *
-Unknown charname '' is deprecated. Its use will be fatal in Perl 5.28
+L<Deprecated use of C<my()> in false conditional. This will be a fatal error in Perl 5.30
+|perldiag/Deprecated use of C<my()> in false conditional. This will be a fatal error in Perl 5.30>
=item *
-Use of bare E<lt>E<lt> to mean E<lt>E<lt>"" is deprecated. Its use will be fatal in Perl 5.28
+L<C<dump()> better written as C<CORE::dump()>. C<dump()> will no longer be available in Perl 5.30
+|perldiag/C<dump()> better written as C<CORE::dump()>. C<dump()> will no longer be available in Perl 5.30>
=item *
-Use of code point 0x%s is deprecated; the permissible max is 0x%s.
-This will be fatal in Perl 5.28
+L<C<${^ENCODING}> is no longer supported. Its use will be fatal in Perl 5.28
+|perldiag/C<${^ENCODING}> is no longer supported. Its use will be fatal in Perl 5.28>
=item *
-Use of comma-less variable list is deprecated. Its use will be fatal
-in Perl 5.28
+L<Experimental %s on scalar is now forbidden This message now is followed by more helpful text.
+L<[perl #127976]|https://rt.perl.org/Public/Bug/Display.html?id=127976>
+|perldiag/Experimental %s on scalar is now forbidden>.
+This message now is followed by more helpful text.
+L<[perl #127976]|https://rt.perl.org/Public/Bug/Display.html?id=127976>
=item *
-Use of inherited AUTOLOAD for non-method %s() is deprecated. This
-will be fatal in Perl 5.28
+L<C<File::Glob::glob()> will disappear in perl 5.30. Use C<File::Glob::bsd_glob()> instead.
+|perldiag/C<File::Glob::glob()> will disappear in perl 5.30. Use C<File::Glob::bsd_glob()> instead.>
=item *
-Use of strings with code points over 0xFF as arguments to %s operator
-is deprecated. This will be a fatal error in Perl 5.28
+L<%s() is deprecated on C<:utf8> handles. This will be a fatal error in Perl 5.30
+|perldiag/%s() is deprecated on C<:utf8> handles. This will be a fatal error in Perl 5.30>.
+"%s" is one of C<sysread>, C<recv>, C<syswrite>, or C<send>.
=item *
-Improve error for missing tie() package/method. This brings the error messages
-in line with the ones used for normal method calls, despite not using
-call_method().
+L<C<$*> is no longer supported. Its use will be fatal in Perl 5.30
+|perldiag/C<$*> is no longer supported. Its use will be fatal in Perl 5.30>
=item *
-Make the sysread()/syswrite/() etc :utf8 handle warnings default. These
-warnings were under 'deprecated' previously.
+L<Opening dirhandle %s also as a file. This will be a fatal error in Perl 5.28
+|perldiag/Opening dirhandle %s also as a file. This will be a fatal error in Perl 5.28>
=item *
-'do' errors now refer to 'do' (not 'require').
+L<Opening filehandle %s also as a directory. This will be a fatal error in Perl 5.28
+|perldiag/Opening filehandle %s also as a directory. This will be a fatal error in Perl 5.28>
=item *
-Details as to the exact problem have been added to the diagnostics that
-occur when malformed UTF-8 is encountered when trying to convert to a
-code point.
+L<Setting C<$/> to a reference to %s as a form of slurp is deprecated, treating as undef. This will be fatal in Perl 5.28
+|perldiag/Setting C<$/> to a reference to %s as a form of slurp is deprecated, treating as undef. This will be fatal in Perl 5.28>
=item *
-Executing C<undef $x> where C<$x> is tied or magical no longer incorrectly
-blames the variable for an uninitialized-value warning encountered by the
-tied/magical code.
+L<Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.30), passed through in regex; marked by S<< E<lt>-- HERE >> in mE<sol>%sE<sol>
+|perldiag/Unescaped left brace in regex is deprecated here (and will be fatal in Perl 5.30), passed through in regex; marked by S<< E<lt>-- HERE >> in m/%s/>
=item *
-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]
+L<Unknown charname '' is deprecated. Its use will be fatal in Perl 5.28
+|perldiag/Unknown charname '' is deprecated. Its use will be fatal in Perl 5.28>
=item *
-When the error "Experimental push on scalar is now forbidden" is raised for
-the hash functions C<keys>, C<each>, and C<values>, it is now followed by
-the more helpful message, "Type of arg 1 to whatever must be hash or
-array". [perl #127976]
+L<Use of bare E<lt>E<lt> to mean E<lt>E<lt>"" is deprecated. Its use will be fatal in Perl 5.28
+|perldiag/Use of bare E<lt>E<lt> to mean E<lt>E<lt>"" is deprecated. Its use will be fatal in Perl 5.28>
=item *
-C<undef *_; shift> or C<undef *_; pop> inside a subroutine, with no
-argument to C<shift> or C<pop>, began crashing in Perl 5.14, but has now
-been fixed.
+L<Use of code point 0x%s is deprecated; the permissible max is 0x%s. This will be fatal in Perl 5.28
+|perldiag/Use of code point 0x%s is deprecated; the permissible max is 0x%s. This will be fatal in Perl 5.28>
=item *
-C<< "string$scalar-E<gt>$*" >> now correctly prefers concat overloading to
-string overloading if C<< $scalar-E<gt>$* >> returns an overloaded object,
-bringing it into consistency with C<$$scalar>.
+L<Use of comma-less variable list is deprecated. Its use will be fatal in Perl 5.28
+|perldiag/Use of comma-less variable list is deprecated. Its use will be fatal in Perl 5.28>
=item *
-C<< /@0{0*-E<gt>@*/*0 >> and similar contortions used to crash, but no longer
-do, but merely produce a syntax error. [perl #128171]
+L<Use of inherited C<AUTOLOAD> for non-method %s() is deprecated. This will be fatal in Perl 5.28
+|perldiag/Use of inherited C<AUTOLOAD> for non-method %s() is deprecated. This will be fatal in Perl 5.28>
=item *
-C<do> or C<require> with a reference or typeglob which, when stringified,
-contains a null character started crashing in Perl 5.20, but has now been
-fixed. [perl #128182]
+L<Use of strings with code points over 0xFF as arguments to %s operator is deprecated. This will be a fatal error in Perl 5.28
+|perldiag/Use of strings with code points over 0xFF as arguments to %s operator is deprecated. This will be a fatal error in Perl 5.28>
=back
=item *
-Account for possibility of DOS file endings.
+Account for the possibility of DOS file endings.
=back
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]
+tests for perlbug.
+L<[perl #128020]|https://rt.perl.org/Public/Bug/Display.html?id=128020>
=back
=item *
-The C<dtrace> build process has further changes:
+The C<dtrace> build process has further changes
+L<[perl #130108]|https://rt.perl.org/Public/Bug/Display.html?id=130108>:
=over
=back
-[perl #130108]
-
=item *
-You can now disable perl's use of the PERL_HASH_SEED and
-PERL_PERTURB_KEYS environment variables by configuring perl with
+You can now disable perl's use of the C<PERL_HASH_SEED> and
+C<PERL_PERTURB_KEYS> environment variables by configuring perl with
C<-Accflags=NO_PERL_HASH_ENV>.
=item *
-You can now disable perl's use of the PERL_HASH_SEED_DEBUG environment
+You can now disable perl's use of the C<PERL_HASH_SEED_DEBUG> environment
variable by configuring perl with
C<-Accflags=-DNO_PERL_HASH_SEED_DEBUG>.
=item *
Zero out the alignment bytes when calculating the bytes for 80-bit C<NaN>
-and C<Inf> to make builds more reproducible. [perl #130133]
+and C<Inf> to make builds more reproducible.
+L<[perl #130133]|https://rt.perl.org/Public/Bug/Display.html?id=130133>
=item *
-Since v5.18 for testing purposes we have included support for
+Since v5.18 for testing purposes, we have included support for
building perl with a variety of non-standard, and non-recommended
hash functions. Since we do not recommend the use of these functions
we have removed them and their corresponding build options. Specifically
Remove "Warning: perl appears in your path"
This install warning is more or less obsolete, since most platforms already
-*will* have a /usr/bin/perl or similar provided by the OS.
+B<will> have a F</usr/bin/perl> or similar provided by the OS.
=item *
-Reduce verbosity of "make install.man"
+Reduce verbosity of C<make install.man>
Previously, two progress messages were emitted for each manpage: one by
installman itself, and one by the function in install_lib.pl that it calls to
=item *
-Cleanup for clang -Weverything support. [perl 129961]
+Cleanup for C<clang -Weverything> support.
+L<[perl #129961]|https://rt.perl.org/Public/Bug/Display.html?id=129961>
=item *
=item *
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
+the C<gai_strerror()> routine is available and can be used to
+translate error codes returned by C<getaddrinfo()> into human
readable strings.
=item *
-F<Configure> now aborts if both "-Duselongdouble" and "-Dusequadmath" are
+F<Configure> now aborts if both C<-Duselongdouble> and C<-Dusequadmath> are
requested.
L<[perl #126203]|https://rt.perl.org/Public/Bug/Display.html?id=126203>
=item *
-Fixed a bug in which F<Configure> could append "-quadmath" to the archname even
+Fixed a bug in which F<Configure> could append C<-quadmath> to the archname even
if it was already present.
L<[perl #128538]|https://rt.perl.org/Public/Bug/Display.html?id=128538>
=item *
-Clang builds with "-DPERL_GLOBAL_STRUCT" or "-DPERL_GLOBAL_STRUCT_PRIVATE" have
+Clang builds with C<-DPERL_GLOBAL_STRUCT> or
+C<-DPERL_GLOBAL_STRUCT_PRIVATE> have
been fixed (by disabling Thread Safety Analysis for these configurations).
=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]
+in particular, to be rebuilt unnecessarily.
+L<[perl #126710]|https://rt.perl.org/Public/Bug/Display.html?id=126710>
=item *
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]
+the headers and proceed to build your cross-target perl.
+L<[perl #127234]|https://rt.perl.org/Public/Bug/Display.html?id=127234>
=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]
+L<[perl #128131]|https://rt.perl.org/Public/Bug/Display.html?id=128131>
=item *
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]
+ago; it has now been restored.
+L<[perl #128052]|https://rt.perl.org/Public/Bug/Display.html?id=128052>
=item *
=item *
-A new test script, F<t/op/decl-refs.t>, has been added to test the new feature,
-"Declaring a reference to a variable".
+A new test script, F<t/op/decl-refs.t>, has been added to test the new feature
+L</Declaring a reference to a variable>.
=item *
=item *
F<t/harness> now tries really hard not to run tests outside of the Perl
-source tree. [perl #124050]
+source tree.
+L<[perl #124050]|https://rt.perl.org/Public/Bug/Display.html?id=124050>
=back
=item Darwin
-don't treat -Dprefix=/usr as special, instead require an extra option
--Ddarwin_distribution to produce the same results.
+don't treat C<-Dprefix=/usr> as special, instead require an extra option
+C<-Ddarwin_distribution> to produce the same results.
=item POSIX
=item OS X
-OS X El Capitan doesn't implement the clock_gettime() or clock_getres() APIs;
-emulate them as necessary.
+OS X El Capitan doesn't implement the C<clock_gettime()> or
+C<clock_getres()> APIs; emulate them as necessary.
=item macOS
-Deprecated syscall(2) on macOS 10.12.
+Deprecated C<syscall(2)> on macOS 10.12.
=item EBCDIC
(containing Visual C++ 14.0) has been added.
This version of VC++ includes a completely rewritten C run-time library, some
-of the changes in which mean that work done to resolve a socket close() bug in
+of the changes in which mean that work done to resolve a socket
+C<close()> bug in
perl #120091 and perl #118059 is not workable in its current state with this
version of VC++. Therefore, we have effectively reverted that bug fix for
VS2015 onwards on the basis that being able to build with VS2015 onwards is
Some incompatibility may arise because of the bug fix that has been reverted
for VS2015 builds of perl, but there may well be incompatibility anyway because
of the rewritten CRT in VS2015 (I<e.g.>, see discussion at
-http://stackoverflow.com/questions/30412951).
+L<http://stackoverflow.com/questions/30412951>).
=back
=item FreeBSD
-t/uni/overload.t: Skip hanging test on FreeBSD.
+F<t/uni/overload.t>: Skip hanging test on FreeBSD.
=back
=item *
-A new API function C<sv_setvpv_bufsize()> allows simultaneously setting the
+A new API function L<C<sv_setpv_bufsize()>|perlapi/sv_setpv_bufsize>
+allows simultaneously setting the
length and allocated size of the buffer in an C<SV>, growing the buffer if
necessary.
=item *
-A new API macro C<SvPVCLEAR()> sets its C<SV> argument to an empty string,
+A new API macro L<C<SvPVCLEAR()>|perlapi/SvPVCLEAR> sets its C<SV>
+argument to an empty string,
like Perl-space C<$x = ''>, but with several optimisations.
=item *
Several new macros and functions for dealing with Unicode and
-UTF-8-encoded strings have been added to the API, as well some changes in
+UTF-8-encoded strings have been added to the API, as well as some
+changes in
functionality of existing functions (see L<perlapi/Unicode Support> for
more details):
=item *
-New versions of macros like C<isALPHA_utf8> and C<toLOWER_utf8> have
-been added, each with the
-suffix C<_safe>, like C<isSPACE_utf8_safe>. These take an extra
-parameter, giving an upper limit of how far into the string it is safe
-to read. Using the old versions could cause attempts to read beyond the
-end of the input buffer if the UTF-8 is not well-formed, and their use
-now raises a deprecation warning. Details are at
-L<perlapi/Character classification>.
+New versions of the API macros like C<isALPHA_utf8> and C<toLOWER_utf8>
+have been added, each with the suffix C<_safe>, like
+L<C<isSPACE_utf8_safe>|perlapi/isSPACE>. These take an extra
+parameter, giving an upper
+limit of how far into the string it is safe to read. Using the old
+versions could cause attempts to read beyond the end of the input buffer
+if the UTF-8 is not well-formed, and their use now raises a deprecation
+
warning. Details are at L<perlapi/Character classification>.
=item *
-Calling macros like C<isALPHA_utf8> on malformed UTF-8 have issued a
-deprecation warning since Perl 5.18. They now die.
-Similarly, macros like C<toLOWER_utf8> on malformed UTF-8 now die.
+Macros like L<C<isALPHA_utf8>|perlapi/isALPHA> and
+L<C<toLOWER_utf8>|perlapi/toLOWER_utf8> now die if they detect
+that their input UTF-8 is malformed. A deprecation warning had been
+issued since Perl 5.18.
=item *
=item *
-Functions that are all extensions of the C<is_utf8_string_*()> functions,
+Functions that are all extensions of the C<is_utf8_string_I<*>()> functions,
that apply various restrictions to the UTF-8 recognized as valid:
L<C<is_strict_utf8_string>|perlapi/is_strict_utf8_string>,
UTF-8 may be syntactically valid, but the code point it represents is
not capable of being represented in the word length on the platform.
What "allowed" means in this case is that the function doesn't return an
-error, and advances the parse pointer to beyond the UTF-8 in question,
-but it returns the Unicode REPLACEMENT CHARACTER as the value of the
-code point (since the real value is not representable).
+error, and it advances the parse pointer to beyond the UTF-8 in
+question, but it returns the Unicode REPLACEMENT CHARACTER as the value
+of the code point (since the real value is not representable).
-C<utf8n_to_uvchr> has been changed to not
-abandon searching for other malformations when the first one is
-encountered. A call to it thus can generate multiple diagnostics,
-instead of just one.
+They no longer abandon searching for other malformations when the first
+one is encountered. A call to one of these functions thus can generate
+multiple diagnostics, instead of just one.
=item *
-C<valid_utf8_to_uvchr()> has been added to the API (although it was
+L<C<valid_utf8_to_uvchr()>|perlapi/valid_utf8_to_uvchr> has been added
+to the API (although it was
present in core earlier). Like C<utf8_to_uvchr_buf()>, but assumes that
-the next character is well-formed.
+the next character is well-formed. Use with caution.
=item *
=item *
-There is now a safer version of utf8_hop(), called utf8_hop_safe().
+There is now a safer version of utf8_hop(), called
+L<C<utf8_hop_safe()>|perlapi/utf8_hop_safe>.
Unlike utf8_hop(), utf8_hop_safe() won't navigate before the beginning or
after the end of the supplied buffer.
=item *
-Two new functions, C<utf8_hop_forward()> and C<utf8_hop_back()> are
+Two new functions, L<C<utf8_hop_forward()>|perlapi/utf8_hop_forward> and
+L<C<utf8_hop_back()>|perlapi/utf8_hop_back> are
similar to C<utf8_hop_safe()> but are for when you know which direction
you wish to travel.
=item *
-The C<op_class()> API function has been added. This is like the existing
+The L<C<op_class()>|perlapi/op_class> API function has been added. This
+is like the existing
C<OP_CLASS()> macro, but can more accurately determine what struct an op
has been allocated as. For example C<OP_CLASS()> might return
C<OA_BASEOP_OR_UNOP> indicating that ops of this type are usually
=item *
-The output format of the C<op_dump()> function (as used by C<perl -Dx>)
+The output format of the L<C<op_dump()>|perlapi/op_dump> function (as
+used by C<perl -Dx>)
has changed: it now displays an "ASCII-art" tree structure, and shows more
low-level details about each op, such as its address and class.
=item *
Perl no longer panics when switching into some locales on machines with
-buggy C<strxfrm()> implementations in their libc. [perl #121734]
+buggy C<strxfrm()> implementations in their libc.
+L<[perl #121734]|https://rt.perl.org/Public/Bug/Display.html?id=121734>
=item *
Attempting to use the deprecated variable C<$#> as the object in an
indirect object method call could cause a heap use after free or
-buffer overflow. [perl #129274]
+buffer overflow.
+L<[perl #129274]|https://rt.perl.org/Public/Bug/Display.html?id=129274>
=item *
When checking for an indirect object method call in some rare cases
the parser could reallocate the line buffer but then continue to use
-pointers to the old buffer. [perl #129190]
+pointers to the old buffer.
+L<[perl #129190]|https://rt.perl.org/Public/Bug/Display.html?id=129190>
=item *
-Supplying a glob as the format argument to L<perlfunc/formline> would
-cause an assertion failure. [perl #130722]
+Supplying a glob as the format argument to
+L<C<formline>|perlfunc/formline> would
+cause an assertion failure.
+L<[perl #130722]|https://rt.perl.org/Public/Bug/Display.html?id=130722>
=item *
Code like C< $value1 =~ qr/.../ ~~ $value2 > would have the match
-converted into a qr// operator, leaving extra elements on the stack to
-confuse any surrounding expression. [perl #130705]
+converted into a C<qr//> operator, leaving extra elements on the stack to
+confuse any surrounding expression.
+L<[perl #130705]|https://rt.perl.org/Public/Bug/Display.html?id=130705>
=item *
Since v5.24 in some obscure cases, a regex which included code blocks
-from multiple sources (I<e.g.>, via embedded via qr// objects) could end up
-with the wrong current pad and crash or give weird results. [perl #129881]
+from multiple sources (I<e.g.>, via embedded via C<qr//> objects) could end up
+with the wrong current pad and crash or give weird results.
+L<[perl #129881]|https://rt.perl.org/Public/Bug/Display.html?id=129881>
=item *
Occasionally C<local()>s in a code block within a patterns weren't being
undone when the pattern matching backtracked over the code block.
-[perl #126697]
+L<[perl #126697]|https://rt.perl.org/Public/Bug/Display.html?id=126697>
=item *
Using C<substr()> to modify a magic variable could access freed memory
-in some cases. [perl #129340]
+in some cases.
+L<[perl #129340]|https://rt.perl.org/Public/Bug/Display.html?id=129340>
=item *
Under C<use utf8>, the entire Perl program is now checked that the UTF-8
-is wellformed. This resolves [perl #126310].
+is wellformed.
+L<[perl #126310]|https://rt.perl.org/Public/Bug/Display.html?id=126310>.
=item *
=item *
-The S<split> operator did not ensure enough space was allocated for
+The C<split> operator did not ensure enough space was allocated for
its return value in scalar context. It could then write a single
pointer immediately beyond the end of the memory block allocated for
-the stack. [perl #130262]
+the stack.
+L<[perl #130262]|https://rt.perl.org/Public/Bug/Display.html?id=130262>
=item *
Using a large code point with the C<"W"> pack template character with
the current output position aligned at just the right point could
cause a write a single zero byte immediately beyond the end of an
-allocated buffer. [perl #129149]
+allocated buffer.
+L<[perl #129149]|https://rt.perl.org/Public/Bug/Display.html?id=129149>
=item *
Supplying the form picture argument as part of the form argument list
where the picture specifies modifying the argument could cause an
-access to the new freed compiled form. [perl #129125]
+access to the new freed compiled form.
+L<[perl #129125]|https://rt.perl.org/Public/Bug/Display.html?id=129125>
=item *
Fix a problem with sort's build-in compare, where it would not sort
-correctly with 64-bit integers, and non-long doubles. [perl #130335]
-
-=item *
-
-Fix issues with /(?{ ... E<lt>E<lt>EOF })/ that broke Method-Signatures. [perl #130398]
+correctly with 64-bit integers, and non-long doubles.
+L<[perl #130335]|https://rt.perl.org/Public/Bug/Display.html?id=130335>
=item *
-Fix a macro which caused syntax error on an EBCDIC build.
+Fix issues with C</(?{ ... E<lt>E<lt>EOF })/> that broke
+L<Method::Signatures>.
+L<[perl #130398]|https://rt.perl.org/Public/Bug/Display.html?id=130398>
=item *
-Prevent tests from getting hung up on 'NonStop' option. [perl #130445]
+Prevent tests from getting hung up on 'NonStop' option.
+L<[perl #130445]|https://rt.perl.org/Public/Bug/Display.html?id=130445>
=item *
Fixed an assertion failure with C<chop> and C<chomp>, which
-could be triggered by C<chop(@x =~ tr/1/1/)>. [perl #130198].
+could be triggered by C<chop(@x =~ tr/1/1/)>.
+L<[perl #130198]|https://rt.perl.org/Public/Bug/Display.html?id=130198>.
=item *
-Fixed a comment skipping error under C</x>; it could stop skipping a
-byte early, which could be in the middle of a UTF-8 character.
-[perl #130495].
+Fixed a comment skipping error in patterns under C</x>; it could stop
+skipping a byte early, which could be in the middle of a UTF-8
+character.
+L<[perl #130495]|https://rt.perl.org/Public/Bug/Display.html?id=130495>.
=item *
-F<perldb> now ignores F</dev/tty> on non-Unix systems. [perl #113960];
+F<perldb> now ignores F</dev/tty> on non-Unix systems.
+L<[perl #113960]|https://rt.perl.org/Public/Bug/Display.html?id=113960>;
=item *
-Fix assertion failure for C<{}-E<gt>$x> when C<$x> isn't defined. [perl #130496].
+Fix assertion failure for C<{}-E<gt>$x> when C<$x> isn't defined.
+L<[perl #130496]|https://rt.perl.org/Public/Bug/Display.html?id=130496>.
=item *
-DragonFly BSD now has support for setproctitle(). [perl #130068].
+DragonFly BSD now has support for C<setproctitle()>.
+L<[perl #130068]|https://rt.perl.org/Public/Bug/Display.html?id=130068>.
=item *
-Fix an assertion error which could be triggered when lookahead string
-in patterns exceeded a minimum length. [perl #130522].
+Fix an assertion error which could be triggered when a lookahead string
+in patterns exceeded a minimum length.
+L<[perl #130522]|https://rt.perl.org/Public/Bug/Display.html?id=130522>.
=item *
-Only warn once per literal about a misplaced C<"_">. [perl #70878].
+Only warn once per literal about a misplaced C<"_">.
+L<[perl #70878]|https://rt.perl.org/Public/Bug/Display.html?id=70878>.
=item *
-Ensure range-start is set after error in C<tr///>. [perl #129342].
+Ensure range-start is set after error in C<tr///>.
+L<[perl #129342]|https://rt.perl.org/Public/Bug/Display.html?id=129342>.
=item *
Don't read past start of string for unmatched backref; otherwise,
-we may have heap buffer overflow. [perl #129377].
+we may have heap buffer overflow.
+L<[perl #129377]|https://rt.perl.org/Public/Bug/Display.html?id=129377>.
=item *
-Properly recognize mathematical digit ranges starting at U+1D7E.
C<use re 'strict'> is supposed to warn if you use a range whose start
and end digit aren't from the same group of 10. It didn't do that
for five groups of mathematical digits starting at U+1D7E.
=item *
-A crash in executing a regex with a floating UTF-8 substring against a
-target string that also used UTF-8 has been fixed. [perl #129350]
+A crash in executing a regex with a non-anchored UTF-8 substring against a
+target string that also used UTF-8 has been fixed.
+L<[perl #129350]|https://rt.perl.org/Public/Bug/Display.html?id=129350>
=item *
The regex engine was previously producing incorrect results in some rare
situations when backtracking past a trie that matches only one thing; this
-showed up as capture buffers (C<$1>, C<$2>, etc) erroneously containing data
+showed up as capture buffers (C<$1>, C<$2>, I<etc.>) erroneously containing data
from regex execution paths that weren't actually executed for the final
-match. [perl #129897]
+match.
+L<[perl #129897]|https://rt.perl.org/Public/Bug/Display.html?id=129897>
=item *
Certain regexes making use of the experimental C<regex_sets> feature could
-trigger an assertion failure. This has been fixed. [perl #129322]
+trigger an assertion failure. This has been fixed.
+L<[perl #129322]|https://rt.perl.org/Public/Bug/Display.html?id=129322>
=item *
Invalid assignments to a reference constructor (I<e.g.>, C<\eval=time>) could
-sometimes crash in addition to giving a syntax error. [perl #125679]
+sometimes crash in addition to giving a syntax error.
+L<[perl #125679]|https://rt.perl.org/Public/Bug/Display.html?id=125679>
=item *
The parser could sometimes crash if a bareword came after C<evalbytes>.
-[perl #129196]
+L<[perl #129196]|https://rt.perl.org/Public/Bug/Display.html?id=129196>
=item *
Autoloading via a method call would warn erroneously ("Use of inherited
AUTOLOAD for non-method") if there was a stub present in the package into
which the invocant had been blessed. The warning is no longer emitted in
-such circumstances. [perl #47047]
-
-=item *
-
-A sub containing with a "forward" declaration with the same name
-(I<e.g.>,
-C<sub c { sub c; }>) could sometimes crash or loop infinitely. [perl
-#129090]
+such circumstances.
+L<[perl #47047]|https://rt.perl.org/Public/Bug/Display.html?id=47047>
=item *
The use of C<splice> on arrays with nonexistent elements could cause other
-operators to crash. [perl #129164]
+operators to crash.
+L<[perl #129164]|https://rt.perl.org/Public/Bug/Display.html?id=129164>
=item *
Fixed case where C<re_untuit_start> will overshoot the length of a utf8
-string. [perl #129012]
+string.
+L<[perl #129012]|https://rt.perl.org/Public/Bug/Display.html?id=129012>
=item *
Handle C<CXt_SUBST> better in C<Perl_deb_stack_all>, previously it wasn't
checking that the I<current> C<cx> is the right type, and instead was always
-checking the base C<cx> (effectively a noop). [perl #129029]
+checking the base C<cx> (effectively a noop).
+L<[perl #129029]|https://rt.perl.org/Public/Bug/Display.html?id=129029>
=item *
Fixed two possible use-after-free bugs in C<Perl_yylex>. C<Perl_yylex>
maintains up to two pointers into the parser buffer, one of which can
-become stale under the right conditions. [perl #129069]
+become stale under the right conditions.
+L<[perl #129069]|https://rt.perl.org/Public/Bug/Display.html?id=129069>
=item *
Fixed a crash with C<s///l> where it thought it was dealing with UTF-8
-when it wasn't. [perl #129038]
+when it wasn't.
+L<[perl #129038]|https://rt.perl.org/Public/Bug/Display.html?id=129038>
=item *
Fixed place where regex was not setting the syntax error correctly.
-[perl #129122]
+L<[perl #129122]|https://rt.perl.org/Public/Bug/Display.html?id=129122>
=item *
was marked as utf8 internally. Many code paths (system calls, regexp
compilation) still expect there to be a null byte in the string buffer
just past the end of the logical string. An assertion failure was the
-result. [perl #129287]
+result.
+L<[perl #129287]|https://rt.perl.org/Public/Bug/Display.html?id=129287>
=item *
silently truncates the supplied path if it won't fit into the C<sun_path>
member of C<sockaddr_un>. This may change in the future, but for now
check the path in theC<sockaddr> matches the desired path, and skip if
-it doesn't. [perl #128095]
+it doesn't.
+L<[perl #128095]|https://rt.perl.org/Public/Bug/Display.html?id=128095>
=item *
Make sure C<PL_oldoldbufptr> is preserved in C<scan_heredoc()>. In some
-cases this is used in building error messages. [perl #128988]
+cases this is used in building error messages.
+L<[perl #128988]|https://rt.perl.org/Public/Bug/Display.html?id=128988>
=item *
-Check for null PL_curcop in IN_LC() [perl #129106]
+Fix segfault when run with C<-DC> options on DEBUGGING builds.
+L<[perl #129106]|https://rt.perl.org/Public/Bug/Display.html?id=129106>
=item *
=item *
Fix C<Perl_delimcpy()> to handle a backslash as last char, this
-actually fixed two bugs, [perl #129064] and [perl #129176].
+actually fixed two bugs,
+L<[perl #129064]|https://rt.perl.org/Public/Bug/Display.html?id=129064> and
+L<[perl #129176]|https://rt.perl.org/Public/Bug/Display.html?id=129176>.
=item *
-[perl #129267] rework gv_fetchmethod_pvn_flags separator parsing to
-prevent possible string overrun with invalid len in gv.c
+L<[perl #129267]|https://rt.perl.org/Public/Bug/Display.html?id=129267> rework C<gv_fetchmethod_pvn_flags> separator parsing to
+prevent possible string overrun with invalid len in F<gv.c>
=item *
=item *
Non-ASCII string delimiters are now reported correctly in error messages
-for unterminated strings. [perl #128701]
+for unterminated strings.
+L<[perl #128701]|https://rt.perl.org/Public/Bug/Display.html?id=128701>
=item *
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 v5.20. [perl #126482]
+from v5.20.
+L<[perl #126482]|https://rt.perl.org/Public/Bug/Display.html?id=126482>
=item *
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 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".
=item *
A regression in v5.24 with C<tr/\N{U+...}/foo/> when the code point was between
-128 and 255 has been fixed. [perl #128734].
+128 and 255 has been fixed.
+L<[perl #128734]|https://rt.perl.org/Public/Bug/Display.html?id=128734>.
=item *
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]
+displayable nor enterable by any editor.
+L<[perl #128738]|https://rt.perl.org/Public/Bug/Display.html?id=128738>
=item *
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]
+L<[perl #128951]|https://rt.perl.org/Public/Bug/Display.html?id=128951>
=item *
=item *
Code that looks for a variable name associated with an uninitialized value
-could cause an assertion in cases where magic is involved, such as
+could cause an assertion failure in cases where magic is involved, such as
C<$ISA[0][0]>. This has now been fixed.
L<[perl #128253]|https://rt.perl.org/Public/Bug/Display.html?id=128253>
=item *
C< until ($x = 1) { ... } > and C< ... until $x = 1 > now properly
-warn when syntax warnings are enabled. [perl #127333]
+warn when syntax warnings are enabled.
+L<[perl #127333]|https://rt.perl.org/Public/Bug/Display.html?id=127333>
=item *
socket() now leaves the error code returned by the system in C<$!> on
-failure. [perl #128316]
+failure.
+L<[perl #128316]|https://rt.perl.org/Public/Bug/Display.html?id=128316>
=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]
+crash if the left-hand side was an array or hash.
+L<[perl #128204]|https://rt.perl.org/Public/Bug/Display.html?id=128204>
=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]
+now parsed correctly as C<require> with implicit C<$_>, rather than
+C<require "">.
+L<[perl #128307]|https://rt.perl.org/Public/Bug/Display.html?id=128307>
=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]
+List assignment now gives a compile-time error, too.
+L<[perl #128260]|https://rt.perl.org/Public/Bug/Display.html?id=128260>
=item *
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]
+bug has now been fixed.
+L<[perl #127952]|https://rt.perl.org/Public/Bug/Display.html?id=127952>
=item *
C<reset> with an argument no longer crashes when encountering stash entries
-other than globs. [perl #128106]
+other than globs.
+L<[perl #128106]|https://rt.perl.org/Public/Bug/Display.html?id=128106>
=item *
Assignment of hashes to, and deletion of, typeglobs named C<*::::::> no
-longer causes crashes. [perl #128086]
+longer causes crashes.
+L<[perl #128086]|https://rt.perl.org/Public/Bug/Display.html?id=128086>
=item *
-Handle SvIMMORTALs in LHS of list assign. [perl #129991]
+Handle C<SvIMMORTALs> in LHS of list assign.
+L<[perl #129991]|https://rt.perl.org/Public/Bug/Display.html?id=129991>
=item *
-[perl #130010] a5540cf breaks texinfo
-
-This involved user-defined Unicode properties.
+Assertion failure with user-defined Unicode-like properties.
+L<[perl #130010]|https://rt.perl.org/Public/Bug/Display.html?id=130010>
=item *
=item *
-[perl 129903]
+Code like this: C</(?{ s!!! })/> can trigger infinite recursion on the C
+stack (not the normal perl stack) when the last successful pattern in
+scope is itself. We avoid the segfault by simply forbidding the use of
+the empty pattern when it would resolve to the currently executing
+pattern.
+L<[perl #129903]|https://rt.perl.org/Public/Bug/Display.html?id=129903>
-The basic problem is that code like this: /(?{ s!!! })/ can trigger infinite
-recursion on the C stack (not the normal perl stack) when the last successful
-pattern in scope is itself. Since the C stack overflows this manifests as an
-untrappable error/segfault, which then kills perl.
+=item *
-We avoid the segfault by simply forbidding the use of the empty pattern when it
-would resolve to the currently executing pattern.
+Avoid reading beyond the end of the line buffer when there's a
+short UTF-8 character at the end.
+L<[perl #128997]|https://rt.perl.org/Public/Bug/Display.html?id=128997>
=item *
-[perl 128997] Avoid reading beyond the end of the line buffer when there's a
-short UTF-8 character at the end.
+Fix firstchar bitmap under utf8 with prefix optimisation.
+L<[perl #129950]|https://rt.perl.org/Public/Bug/Display.html?id=129950>
+
+=item *
+
+Make F<Carp/t/arg_string.t>: be liberal in C<f>/C<p> formats.
+L<[perl #129954]|https://rt.perl.org/Public/Bug/Display.html?id=129954>
+
+=item *
+
+Make C<do "a\0b"> fail silently instead of throwing an error.
+L<[perl #129928]|https://rt.perl.org/Public/Bug/Display.html?id=129928>
+
+=item *
+
+Make C<chdir> allocate the stack it needs.
+L<[perl #129130]|https://rt.perl.org/Public/Bug/Display.html?id=129130>
+
+=item *
+
+C<do> errors now refer to C<do> (not C<require>).
+
+=item *
+
+Executing C<undef $x> where C<$x> is tied or magical no longer incorrectly
+blames the variable for an uninitialized-value warning encountered by the
+tied/magical code.
+
+=item *
+
+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.
+L<[perl #127877]|https://rt.perl.org/Public/Bug/Display.html?id=127877>
=item *
-[perl 129950] fix firstchar bitmap under utf8 with prefix optimisation.
+C<undef *_; shift> or C<undef *_; pop> inside a subroutine, with no
+argument to C<shift> or C<pop>, began crashing in Perl 5.14, but has now
+been fixed.
+
+=item *
+
+C<< "string$scalar-E<gt>$*" >> now correctly prefers concat overloading to
+string overloading if C<< $scalar-E<gt>$* >> returns an overloaded object,
+bringing it into consistency with C<$$scalar>.
=item *
-[perl 129954] Carp/t/arg_string.t: be liberal in f/p formats.
+C<< /@0{0*-E<gt>@*/*0 >> and similar contortions used to crash, but no longer
+do, but merely produce a syntax error.
+L<[perl #128171]|https://rt.perl.org/Public/Bug/Display.html?id=128171>
=item *
-[perl 129928] make do "a\0b" fail silently instead of throwing.
+C<do> or C<require> with a reference or typeglob which, when stringified,
+contains a null character started crashing in Perl 5.20, but has now been
+fixed.
+L<[perl #128182]|https://rt.perl.org/Public/Bug/Display.html?id=128182>
=item *
-[perl 129130] make chdir allocate the stack it needs.
+Improve error for missing C<tie()> package/method. This brings the error messages
+in line with the ones used for normal method calls, despite not using
+call_method().
=back
=item *
Some modules have been broken by the L<context stack rework|/Internal Changes>.
-These modules were relying on non-guaranteed implementation details in perl.
+These modules were relying on non-guaranteed implementation details in
+the perl interpreter.
Their maintainers have been informed, and should contact perl5-porters for
advice if needed. Below is a subset of these modules:
=item * L<Coro>
-L<Coro> and Perl 5.22 were already incompatible due to a change in the perl,
+L<Coro> and Perl 5.22 were already incompatible due to a change in the perl
+interpreter,
and the reworking on the perl context stack creates a further incompatibility.
perl5-porters has L<discussed the issue on the mailing
list|http://www.nntp.perl.org/group/perl.perl5.porters/2016/05/msg236174.html>.
https://perl5.git.perl.org / perl5.git / blobdiff