-Its compilation speed has been improved slightly.
-
-=item *
-
-L<parent> has been upgraded from version 0.234 to 0.236.
-
-=item *
-
-L<perl5db.pl> has been upgraded from version 1.50 to 1.51.
-
-It now ignores F</dev/tty> on non-Unix systems.
-L<[perl #113960]|https://rt.perl.org/Public/Bug/Display.html?id=113960>
-
-=item *
-
-L<Perl::OSType> has been upgraded from version 1.009 to 1.010.
-
-=item *
-
-L<perlfaq> has been upgraded from version 5.021010 to 5.021011.
-
-=item *
-
-L<PerlIO> has been upgraded from version 1.09 to 1.10.
-
-=item *
-
-L<PerlIO::encoding> has been upgraded from version 0.24 to 0.25.
-
-=item *
-
-L<PerlIO::scalar> has been upgraded from version 0.24 to 0.26.
-
-=item *
-
-L<Pod::Checker> has been upgraded from version 1.60 to 1.73.
-
-=item *
-
-L<Pod::Functions> has been upgraded from version 1.10 to 1.11.
-
-=item *
-
-L<Pod::Html> has been upgraded from version 1.22 to 1.2202.
-
-=item *
-
-L<Pod::Perldoc> has been upgraded from version 3.25_02 to 3.28.
-
-=item *
-
-L<Pod::Simple> has been upgraded from version 3.32 to 3.35.
-
-=item *
-
-L<Pod::Usage> has been upgraded from version 1.68 to 1.69.
-
-=item *
-
-L<POSIX> has been upgraded from version 1.65 to 1.76.
-
-This remedies several 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">.
-
-The following deprecated functions have been removed:
-
- POSIX::isalnum
- POSIX::isalpha
- POSIX::iscntrl
- POSIX::isdigit
- POSIX::isgraph
- POSIX::islower
- POSIX::isprint
- POSIX::ispunct
- POSIX::isspace
- POSIX::isupper
- POSIX::isxdigit
- POSIX::tolower
- POSIX::toupper
-
-Trying to import POSIX subs that have no real implementations
-(like C<POSIX::atend()>) now fails at import time, instead of
-waiting until runtime.
-
-=item *
-
-L<re> has been upgraded from version 0.32 to 0.34
-
-This adds support for the new L<C<E<47>xx>|perlre/E<sol>x and E<sol>xx>
-regular expression pattern modifier, and a change to the L<S<C<use re
-'strict'>>|re/'strict' mode> experimental feature. When S<C<re
-'strict'>> is enabled, a warning now will be generated for all
-unescaped uses of the two characters C<"}"> and C<"]"> in regular
-expression patterns (outside bracketed character classes) that are taken
-literally. This brings them more in line with the C<")"> character which
-is always a metacharacter unless escaped. Being a metacharacter only
-sometimes, depending on an action at a distance, can lead to silently
-having the pattern mean something quite different than was intended,
-which the S<C<re 'strict'>> mode is intended to minimize.
-
-=item *
-
-L<Safe> has been upgraded from version 2.39 to 2.40.
-
-=item *
-
-L<Scalar::Util> has been upgraded from version 1.42_02 to 1.46_02.
-
-=item *
-
-L<Storable> has been upgraded from version 2.56 to 2.62.
-
-Fixes
-L<[perl #130098]|https://rt.perl.org/Public/Bug/Display.html?id=130098>.
-
-=item *
-
-L<Symbol> has been upgraded from version 1.07 to 1.08.
-
-=item *
-
-L<Sys::Syslog> has been upgraded from version 0.33 to 0.35.
-
-=item *
-
-L<Term::ANSIColor> has been upgraded from version 4.04 to 4.06.
-
-=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()>.
-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()>.
-L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
-
-=item *
-
-L<Test::Harness> has been upgraded from version 3.36 to 3.38.
-
-=item *
-
-L<Test::Simple> has been upgraded from version 1.001014 to 1.302073.
-
-=item *
-
-L<Thread::Queue> has been upgraded from version 3.09 to 3.12.
-
-=item *
-
-L<Thread::Semaphore> has been upgraded from 2.12 to 2.13.
-
-Added the C<down_timed> method.
-
-=item *
-
-L<threads> has been upgraded from version 2.07 to 2.15.
-
-=item *
-
-L<threads::shared> has been upgraded from version 1.51 to 1.56.
-
-=item *
-
-L<Tie::Hash::NamedCapture> has been upgraded from version 0.09 to 0.10.
-
-=item *
-
-L<Time::HiRes> has been upgraded from version 1.9733 to 1.9741.
-
-It now builds on systems with C++11 compilers (such as G++ 6 and Clang++
-3.9).
-
-Now uses C<clockid_t>.
-
-=item *
-
-L<Time::Local> has been upgraded from version 1.2300 to 1.25.
-
-=item *
-
-L<Unicode::Collate> has been upgraded from version 1.14 to 1.19.
-
-=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()>.
-L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
-
-=item *
-
-L<version> has been upgraded from version 0.9916 to 0.9917.
-
-=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()>.
-L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
-
-=item *
-
-L<warnings> has been upgraded from version 1.36 to 1.37.
-
-=item *
-
-L<XS::Typemap> has been upgraded from version 0.14 to 0.15.
-
-=item *
-
-L<XSLoader> has been upgraded from version 0.21 to 0.27.
-
-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()>.
-L<[perl #130122]|https://rt.perl.org/Public/Bug/Display.html?id=130122>
-
-=back
-
-=head1 Documentation
-
-=head2 New Documentation
-
-=head3 L<perldeprecation>
-
-This file documents all upcoming deprecations, and some of the deprecations
-which already have been removed. The purpose of this documentation is
-two-fold: document what will disappear, and by which version, and serve
-as a guide for people dealing with code which has features that no longer
-work after an upgrade of their perl.
-
-=head2 Changes to Existing Documentation
-
-We have attempted to update the documentation to reflect the changes
-listed in this document. If you find any we have missed, send email to
-L<perlbug@perl.org|mailto:perlbug@perl.org>.
-
-Additionally, all references to Usenet have been removed, and the
-following selected changes have been made:
-
-=head3 L<perlfunc>
-
-=over 4
-
-=item *
-
-Removed obsolete text about L<C<defined()>|perlfunc/defined>
-on aggregates that should have been deleted earlier, when the feature
-was removed.
-
-=item *
-
-Corrected documentation of L<C<eval()>|perlfunc/eval>,
-and L<C<evalbytes()>|perlfunc/evalbytes>.
-
-=item *
-
-Clarified documentation of L<C<seek()>|perlfunc/seek>,
-L<C<tell()>|perlfunc/tell> and L<C<sysseek()>|perlfunc/sysseek>
-emphasizing that positions are in bytes and not characters.
-L<[perl #128607]|https://rt.perl.org/Public/Bug/Display.html?id=128607>
-
-=item *
-
-Clarified documentation of L<C<sort()>|perlfunc/sort LIST> concerning
-the variables C<$a> and C<$b>.
-
-=item *
-
-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 *
-
-Removed obsolete documentation of L<C<study()>|perlfunc/study>, noting
-that it is now a no-op.
-
-=item *
-
-Noted that L<C<vec()>|perlfunc/vec> doesn't work well when the string
-contains characters whose code points are above 255.
-
-=back
-
-=head3 L<perlguts>
-
-=over 4
-
-=item *
-
-Added advice on
-L<formatted printing of operands of C<Size_t> and C<SSize_t>|perlguts/Formatted Printing of Size_t and SSize_t>
-
-=back
-
-=head3 L<perlhack>
-
-=over 4
-
-=item *
-
-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
-
-=head3 L<perlhacktips>
-
-=over 4
-
-=item *
-
-Give another reason to use C<cBOOL> to cast an expression to boolean.
-
-=item *
-
-Note that the macros C<TRUE> and C<FALSE> are available to express
-boolean values.
-
-=back
-
-=head3 L<perlinterp>
-
-=over 4
-
-=item *
-
-L<perlinterp> has been expanded to give a more detailed example of how to
-hunt around in the parser for how a given operator is handled.
-
-=back
-
-=head3 L<perllocale>
-
-=over 4
-
-=item *
-
-Some locales aren't compatible with Perl. Note that these can cause
-core dumps.
-
-=back
-
-=head3 L<perlmod>
-
-=over 4
-
-=item *
-
-Various clarifications have been added.
-
-=back
-
-=head3 L<perlmodlib>
-
-=over 4
-
-=item *
-
-Updated the site mirror list.
-
-=back
-
-=head3 L<perlobj>
-
-=over 4
-
-=item *
-
-Added a section on calling methods using their fully qualified names.
-
-=item *
-
-Do not discourage manual C<@ISA>.
-
-=back
-
-=head3 L<perlootut>
-
-=over 4
-
-=item *
-
-Mention C<Moo> more.
-
-=back
-
-=head3 L<perlop>
-
-=over 4
-
-=item *
-
-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
-
-=head3 L<perlre>
-
-=over 4
-
-=item *
-
-The first part was extensively rewritten to incorporate various basic
-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.
-
-=back
-
-=head3 L<perlretut>
-
-=over 4
-
-=item *
-
-Add introductory material.
-
-=item *
-
-Note that a metacharacter occurring in a context where it can't mean
-that, silently loses its meta-ness and matches literally.
-L<C<use re 'strict'>|re/'strict' mode> can catch some of these.
-
-=back
-
-=head3 L<perlunicode>
-
-=over 4
-
-=item *
-
-Corrected the text about Unicode BYTE ORDER MARK handling.
-
-=item *
-
-Updated the text to correspond with changes in Unicode UTS#18, concerning
-regular expressions, and Perl compatibility with what it says.
-
-=back
-
-=head3 L<perlvar>
-
-=over 4
-
-=item *
-
-Document C<@ISA>. It was documented in other places, but not in L<perlvar>.
-
-=back
-
-=head1 Diagnostics
-
-=head2 New Diagnostics
-
-=head3 New Errors
-
-=over 4
-
-=item *
-
-L<A signature parameter must start with C<'$'>, C<'@'> or C<'%'>
-|perldiag/A signature parameter must start with C<'$'>, C<'@'> or C<'%'>>
-
-=item *
-
-L<Bareword in require contains "%s"|perldiag/"Bareword in require contains "%s"">
-
-=item *
-
-L<Bareword in require maps to empty filename|perldiag/"Bareword in require maps to empty filename">
-
-=item *
-
-L<Bareword in require maps to disallowed filename "%s"|perldiag/"Bareword in require maps to disallowed filename "%s"">
-
-=item *
-
-L<Bareword in require must not start with a double-colon: "%s"|perldiag/"Bareword in require must not start with a double-colon: "%s"">
-
-=item *
-
-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 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
-
-=item *
-
-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 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
-
-=item *
-
-L<The experimental declared_refs feature is not enabled|perldiag/"The experimental declared_refs feature is not enabled">
-
-(F) To declare references to variables, as in C<my \%x>, you must first enable
-the feature:
-
- no warnings "experimental::declared_refs";
- use feature "declared_refs";
-
-See L</Declaring a reference to a variable>.
-
-=item *
-
-L<Illegal character following sigil in a subroutine signature
-|perldiag/Illegal character following sigil in a subroutine signature>
-
-=item *
-
-L<Indentation on line %d of here-doc doesn't match delimiter
-|perldiag/Indentation on line %d of here-doc doesn't match delimiter>
-
-=item *
-
-L<Infinite recursion via empty pattern|perldiag/"Infinite recursion via empty pattern">.
-
-Using the empty pattern (which re-executes the last successfully-matched
-pattern) inside a code block in another regex, as in C</(?{ s!!new! })/>, has
-always previously yielded a segfault. It now produces this error.
-
-=item *
-
-L<Malformed UTF-8 string in "%s"
-|perldiag/Malformed UTF-8 string in "%s">
-
-=item *
-
-L<Multiple slurpy parameters not allowed
-|perldiag/Multiple slurpy parameters not allowed>
-
-=item *
-
-L<C<'#'> not allowed immediately following a sigil in a subroutine signature
-|perldiag/C<'#'> not allowed immediately following a sigil in a subroutine signature>
-
-=item *
-
-L<panic: unknown OA_*: %x
-|perldiag/panic: unknown OA_*: %x>
-
-=item *
-
-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>>
-
-Unescaped left braces are now illegal in some contexts in regular expression
-patterns. In other contexts, they are still just deprecated; they will
-be illegal in Perl 5.30.
-
-=item *
-
-L<Version control conflict marker|perldiag/"Version control conflict marker">
-
-(F) The parser found a line starting with C<E<lt>E<lt>E<lt>E<lt>E<lt>E<lt>E<lt>>,
-C<E<gt>E<gt>E<gt>E<gt>E<gt>E<gt>E<gt>>, or C<=======>. These may be left by a
-version control system to mark conflicts after a failed merge operation.
-
-=back
-
-=head3 New Warnings
-
-=over 4
-
-=item *
-
-L<Can't determine class of operator %s, assuming C<BASEOP>
-|perldiag/Can't determine class of operator %s, assuming C<BASEOP>>
-
-=item *
-
-L<Declaring references is experimental|perldiag/"Declaring references is experimental">
-
-(S experimental::declared_refs) This warning is emitted if you use a reference
-constructor on the right-hand side of C<my()>, C<state()>, C<our()>, or
-C<local()>. Simply suppress the warning if you want to use the feature, but
-know that in doing so you are taking the risk of using an experimental feature
-which may change or be removed in a future Perl version:
-
- no warnings "experimental::declared_refs";
- use feature "declared_refs";
- $fooref = my \$foo;
-
-See L</Declaring a reference to a variable>.
-
-=item *
-
-L<do "%s" failed, '.' is no longer in @INC|perldiag/do "%s" failed, '.' is no longer in @INC; did you mean do ".E<sol>%s"?>
-
-Since C<"."> is now removed from C<@INC> by default, C<do> will now trigger a warning recommending to fix the C<do> statement.
-
-=item *
-
-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 *
-
-L<Unescaped literal '%c' in regex; marked by E<lt>-- HERE in mE<sol>%sE<sol>
-|perldiag/Unescaped literal '%c' in regex; marked by <-- HERE in mE<sol>%sE<sol>>
-
-=item *
-
-L<Use of unassigned code point or non-standalone grapheme for a delimiter will be a fatal error starting in Perl 5.30|perldiag/"Use of unassigned code point or non-standalone grapheme for a delimiter will be a fatal error starting in Perl 5.30">
-
-See L</Deprecations>
-
-=back
-
-=head2 Changes to Existing Diagnostics
-
-=over 4
-
-=item *
-
-When a C<require> fails, we now do not provide C<@INC> when the C<require>
-is for a file instead of a module.
-
-=item *
-
-When C<@INC> is not scanned for a C<require> call, we no longer display
-C<@INC> to avoid confusion.
-
-=item *
-
-L<Attribute "locked" is deprecated, and will disappear in Perl 5.28
-|perldiag/Attribute "locked" is deprecated, and will disappear in Perl 5.28>
-
-This existing warning has had the I<and will disappear> text added in this
-release.
-
-=item *
-
-L<Attribute "unique" is deprecated, and will disappear in Perl 5.28
-|perldiag/Attribute "unique" is deprecated, and will disappear in Perl 5.28>
-
-This existing warning has had the I<and will disappear> text added in this
-release.
-
-=item *
-
-Calling POSIX::%s() is deprecated
-
-This warning has been removed, as the deprecated functions have been
-removed from POSIX.
-
-=item *
-
-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>
-
-This existing warning has had the I<this will not be allowed> text added
-in this release.
-
-=item *
-
-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>
-
-This existing warning has had the I<this will be a fatal error> text added
-in this release.
-
-=item *
-
-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>
-
-This existing warning has had the I<no longer be available> text added in
-this release.
-
-=item *
-
-L<Experimental %s on scalar is now forbidden
-|perldiag/Experimental %s on scalar is now forbidden>
-
-This message is now followed by more helpful text.
-L<[perl #127976]|https://rt.perl.org/Public/Bug/Display.html?id=127976>
-
-=item *
-
-Experimental "%s" subs not enabled
-
-This warning was been removed, as lexical subs are no longer experimental.
-
-=item *
-
-Having more than one /%c regexp modifier is deprecated
-
-This deprecation warning has been removed, since C</xx> now has a new
-meaning.
-
-=item *
-
-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>.
-
-where "%s" is one of C<sysread>, C<recv>, C<syswrite>, or C<send>.
-
-This existing warning has had the I<this will be a fatal error> text added
-in this release.
-
-This warning is now enabled by default, as all C<deprecated> category
-warnings should be.
-
-=item *
-
-L<C<$*> is no longer supported. Its use will be fatal in Perl 5.30
-|perldiag/C<$*> is no longer supported. Its use will be fatal in Perl 5.30>
-
-This existing warning has had the I<its use will be fatal> text added in
-this release.
-
-=item *
-
-L<C<$#> 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>
-
-This existing warning has had the I<its use will be fatal> text added in
-this release.
-
-=item *
-
-L<Malformed UTF-8 character%s
-|perldiag/Malformed UTF-8 character%s>
-
-Details as to the exact problem have been added at the end of this
-message
-
-=item *
-
-L<Missing or undefined argument to %s
-|perldiag/Missing or undefined argument to %s>
-
-This warning used to warn about C<require>, even if it was actually C<do>
-which being executed. It now gets the operation name right.
-
-=item *
-
-NO-BREAK SPACE in a charnames alias definition is deprecated
-
-This warning has been removed as the behavior is now an error.
-
-=item *
-
-L<Odd nameE<sol>value argument for subroutine '%s'
-|perldiag/"Odd nameE<sol>value argument for subroutine '%s'">
-
-This warning now includes the name of the offending subroutine.
-
-=item *
-
-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>
-
-This existing warning has had the I<this will be a fatal error> text added
-in this release.
-
-=item *
-
-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>
-
-This existing warning has had the I<this will be a fatal error> text added
-in this release.
-
-=item *
-
-panic: ck_split, type=%u
-
-panic: pp_split, pm=%p, s=%p
-
-These panic errors have been removed.
-
-=item *
-
-Passing malformed UTF-8 to "%s" is deprecated
-
-This warning has been changed to the fatal
-L<Malformed UTF-8 string in "%s"
-|perldiag/Malformed UTF-8 string in "%s">
-
-=item *
-
-L<Setting C<< $E<sol> >> 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<< $E<sol> >> to a reference to %s as a form of slurp is deprecated, treating as undef. This will be fatal in Perl 5.28>
-
-This existing warning has had the I<this will be fatal> text added in
-this release.
-
-=item *
-
-L<C<${^ENCODING}> is no longer supported. Its use will be fatal in Perl 5.28|perldiag/"${^ENCODING} is no longer supported. Its use will be fatal in Perl 5.28">
-
-This warning used to be: "Setting C<${^ENCODING}> is deprecated".
-
-The special action of the variable C<${^ENCODING}> was formerly used to
-implement the C<encoding> pragma. As of Perl 5.26, rather than being
-deprecated, assigning to this variable now has no effect except to issue
-the warning.
-
-=item *
-
-L<Too few arguments for subroutine '%s'
-|perldiag/Too few arguments for subroutine '%s'>
-
-This warning now includes the name of the offending subroutine.
-
-=item *
-
-L<Too many arguments for subroutine '%s'
-|perldiag/Too many arguments for subroutine '%s'>
-
-This warning now includes the name of the offending subroutine.
-
-=item *
-
-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 mE<sol>%sE<sol>>
-
-This existing warning has had the I<here (and will be fatal...)> text
-added in this release.
-
-=item *
-
-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>
-
-This existing warning has had the I<its use will be fatal> text added in
-this release.
-
-=item *
-
-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>
-
-This existing warning has had the I<its use will be fatal> text added in
-this release.
-
-=item *
-
-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>
-
-This existing warning has had the I<this will be fatal> text added in
-this release.
-
-=item *
-
-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>
-
-This existing warning has had the I<its use will be fatal> text added in
-this release.
-
-=item *
-
-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>
-
-This existing warning has had the I<this will be fatal> text added in
-this release.
-
-=item *
-
-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>
-
-This existing warning has had the I<this will be a fatal error> text added in
-this release.
-
-=back
-
-=head1 Utility Changes
-
-=head2 F<c2ph> and F<pstruct>
-
-=over 4
-
-=item *
-
-These old utilities have long since superceded by L<h2xs>, and are
-now gone from the distribution.
-
-=back
-
-=head2 F<Porting/pod_lib.pl>
-
-=over 4
-
-=item *
-
-Removed spurious executable bit.
-
-=item *
-
-Account for the possibility of DOS file endings.
-
-=back
-
-=head2 F<Porting/sync-with-cpan>
-
-=over 4
-
-=item *
-
-Many improvements.
-
-=back
-
-=head2 F<perf/benchmarks>
-
-=over 4
-
-=item *
-
-Tidy file, rename some symbols.
-
-=back
-
-=head2 F<Porting/checkAUTHORS.pl>
-
-=over 4
-
-=item *
-
-Replace obscure character range with C<\w>.
-
-=back
-
-=head2 F<t/porting/regen.t>
-
-=over 4
-
-=item *
-
-Try to be more helpful when tests fail.
-
-=back
-
-=head2 F<utils/h2xs.PL>
-
-=over 4
-
-=item *
-
-Avoid infinite loop for enums.
-
-=back
-
-=head2 L<perlbug>
-
-=over 4
-
-=item *
-
-Long lines in the message body are now wrapped at 900 characters, to stay
-well within the 1000-character limit imposed by SMTP mail transfer agents.
-This is particularly likely to be important for the list of arguments to
-F<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.
-L<[perl #128020]|https://rt.perl.org/Public/Bug/Display.html?id=128020>
-
-=back
-
-=head1 Configuration and Compilation
-
-=over 4
-
-=item *
-
-C<-Ddefault_inc_excludes_dot> has added, and enabled by default.
-
-=item *
-
-The C<dtrace> build process has further changes
-L<[perl #130108]|https://rt.perl.org/Public/Bug/Display.html?id=130108>:
-
-=over
-
-=item *
-
-If the C<-xnolibs> is available, use that so a F<dtrace> perl can be
-built within a FreeBSD jail.
-
-=item *
-
-On systems that build a F<dtrace> object file (FreeBSD, Solaris, and
-SystemTap's dtrace emulation), copy the input objects to a separate
-directory and process them there, and use those objects in the link,
-since C<dtrace -G> also modifies these objects.
-
-=item *
-
-Add F<libelf> to the build on FreeBSD 10.x, since F<dtrace> adds
-references to F<libelf> symbols.
-
-=item *
-
-Generate a dummy F<dtrace_main.o> if C<dtrace -G> fails to build it. A
-default build on Solaris generates probes from the unused inline
-functions, while they don't on FreeBSD, which causes C<dtrace -G> to
-fail.
-
-=back
-
-=item *
-
-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 C<PERL_HASH_SEED_DEBUG> environment
-variable by configuring perl with
-C<-Accflags=-DNO_PERL_HASH_SEED_DEBUG>.
-
-=item *
-
-F<Configure> now zeroes out the alignment bytes when calculating the bytes
-for 80-bit C<NaN> 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
-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
-this includes the following build options:
-
- PERL_HASH_FUNC_SDBM
- PERL_HASH_FUNC_DJB2
- PERL_HASH_FUNC_SUPERFAST
- PERL_HASH_FUNC_MURMUR3
- PERL_HASH_FUNC_ONE_AT_A_TIME
- PERL_HASH_FUNC_ONE_AT_A_TIME_OLD
- PERL_HASH_FUNC_MURMUR_HASH_64A
- PERL_HASH_FUNC_MURMUR_HASH_64B
-
-=item *
-
-Remove "Warning: perl appears in your path"
-
-This install warning is more or less obsolete, since most platforms already
-B<will> have a F</usr/bin/perl> or similar provided by the OS.
-
-=item *
-
-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 F<install_lib.pl> that it calls to
-actually install the file. Disabling the second of those in each case saves
-over 750 lines of unhelpful output.
-
-=item *
-
-Cleanup for C<clang -Weverything> support.
-L<[perl #129961]|https://rt.perl.org/Public/Bug/Display.html?id=129961>
-
-=item *
-
-F<Configure>: signbit scan was assuming too much, stop assuming negative 0.
-
-=item *
-
-Various compiler warnings have been silenced.
-
-=item *
-
-Several smaller changes have been made to remove impediments to compiling
-under C++11.
-
-=item *
-
-Builds using C<USE_PAD_RESET> now work again; this configuration had
-bit-rotted.
-
-=item *
-
-A probe for C<gai_strerror> was added to F<Configure> that checks if
-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 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 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 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.
-L<[perl #126710]|https://rt.perl.org/Public/Bug/Display.html?id=126710>
-
-=item *
-
-The output of C<perl -V> has been reformatted so that each configuration
-and compile-time option is now listed one per line, to improve
-readability.
-
-=item *
-
-F<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.
-L<[perl #127234]|https://rt.perl.org/Public/Bug/Display.html?id=127234>
-
-=item *
-
-Perl built with C<-Accflags=-DPERL_TRACE_OPS> now only dumps the operator
-counts when the environment variable C<PERL_TRACE_OPS> is set to a
-non-zero integer. This allows C<make test> to pass on such a build.
-
-=item *
-
-When building with GCC 6 and link-time optimization (the C<-flto> option to
-C<gcc>), F<Configure> was treating all probed symbols as present on the
-system, regardless of whether they actually exist. This has been fixed.
-L<[perl #128131]|https://rt.perl.org/Public/Bug/Display.html?id=128131>
-
-=item *
-
-The F<t/test.pl> library is used for internal testing of Perl itself, and
-also copied by several CPAN modules. Some of those modules must work on
-older versions of Perl, so F<t/test.pl> must in turn avoid newer Perl
-features. Compatibility with Perl 5.8 was inadvertently removed some time
-ago; it has now been restored.
-L<[perl #128052]|https://rt.perl.org/Public/Bug/Display.html?id=128052>
-
-=item *
-
-The build process no longer emits an extra blank line before building each
-"simple" extension (those with only F<*.pm> and F<*.pod> files).
-
-=back
-
-=head1 Testing
-
-Tests were added and changed to reflect the other additions and changes
-in this release. Furthermore, these substantive changes were made:
-
-=over 4
-
-=item *
-
-A new test script, F<comp/parser_run.t>, has been added that is like
-F<comp/parser.t> but with F<test.pl> included so that C<runperl()> and the
-like are available for use.
-
-=item *
-
-Tests for locales were erroneously using locales incompatible with Perl.
-
-=item *
-
-Some parts of the test suite that try to exhaustively test edge cases in the
-regex implementation have been restricted to running for a maximum of five
-minutes. On slow systems they could otherwise take several hours, without
-significantly improving our understanding of the correctness of the code
-under test.
-
-=item *
-
-A new internal facility allows analysing the time taken by the individual
-tests in Perl's own test suite; see F<Porting/harness-timer-report.pl>.
-
-=item *
-
-F<t/re/regexp_nonull.t> has been added to test that the regular expression
-engine can handle scalars that do not have a null byte just past the end of
-the string.
-
-=item *
-
-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 *
-
-A new test script, F<t/re/keep_tabs.t> has been added to contain tests
-where C<\t> characters should not be expanded into spaces.
-
-=item *
-
-A new test script, F<t/re/anyof.t>, has been added to test that the ANYOF nodes
-generated by bracketed character classes are as expected.
-
-=item *
-
-There is now more extensive testing of the Unicode-related API macros
-and functions.
-
-=item *
-
-Several of the longer running API test files have been split into
-multiple test files so that they can be run in parallel.
-
-=item *
-
-F<t/harness> now tries really hard not to run tests which are located
-outside of the Perl source tree.
-L<[perl #124050]|https://rt.perl.org/Public/Bug/Display.html?id=124050>
-
-=item *
-
-Prevent debugger tests (F<lib/perl5db.t>) from failing due to the contents
-of C<$ENV{PERLDB_OPTS}>.
-L<[perl #130445]|https://rt.perl.org/Public/Bug/Display.html?id=130445>
-
-=back
-
-=head1 Platform Support
-
-=head2 New Platforms
-
-=over 4
-
-=item NetBSD/VAX
-
-Perl now compiles under NetBSD on VAX machines. However, it's not
-possible for that platform to implement floating-point infinities and
-NaNs compatible with most modern systems, which implement the IEEE-754
-floating point standard. The hexadecimal floating point (C<0x...p[+-]n>
-literals, C<printf %a>) is not implemented, either.
-The C<make test> passes 98% of tests.
-
-=over 4
-
-=item *
-
-Test fixes and minor updates.
-
-=item *
-
-Account for lack of C<inf>, C<nan>, and C<-0.0> support.
-
-=back
-
-=back
-
-=head2 Platform-Specific Notes
-
-=over 4
-
-=item Darwin
-
-=over 4
-
-=item *
-
-Don't treat C<-Dprefix=/usr> as special: instead require an extra option
-C<-Ddarwin_distribution> to produce the same results.
-
-=item *
-
-OS X El Capitan doesn't implement the C<clock_gettime()> or
-C<clock_getres()> APIs; emulate them as necessary.
-
-=item *
-
-Deprecated C<syscall(2)> on macOS 10.12.
-
-=back
-
-=item EBCDIC
-
-Several tests have been updated to work (or be skipped) on EBCDIC platforms.
-
-=item HP-UX
-
-The L<Net::Ping> UDP test is now skipped on HP-UX.
-
-=item Hurd
-
-The hints for Hurd have been improved, enabling malloc wrap and reporting the
-GNU libc used (previously it was an empty string when reported).
-
-=item VAX
-
-VAX floating point formats are now supported on NetBSD.
-
-=item VMS
-
-=over 4
-
-=item *
-
-The path separator for the C<PERL5LIB> and C<PERLLIB> environment entries is
-now a colon (C<":">) when running under a Unix shell. There is no change when
-running under DCL (it's still C<"|">).
-
-=item *
-
-F<configure.com> now recognizes the VSI-branded C compiler and no longer
-recognizes the "DEC"-branded C compiler (as there hasn't been such a thing for
-15 or more years).
-
-=back
-
-=item Windows
-
-=over 4
-
-=item *
-
-Support for compiling perl on Windows using Microsoft Visual Studio 2015
-(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
-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
-more important than keeping the bug fix. We may revisit this in the future to
-attempt to fix the bug again in a way that is compatible with VS2015.
-
-These changes do not affect compilation with GCC or with Visual Studio versions
-up to and including VS2013, I<i.e.>, the bug fix is retained (unchanged) for those
-compilers.
-
-Note that you may experience compatibility problems if you mix a perl built
-with GCC or VS E<lt>= VS2013 with XS modules built with VS2015, or if you mix a
-perl built with VS2015 with XS modules built with GCC or VS E<lt>= VS2013.
-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
-L<http://stackoverflow.com/questions/30412951>).
-
-=item *
-
-It now automatically detects GCC versus Visual C and sets the VC version
-number on Win32.
-
-=back
-
-=item Linux
-
-Drop support for Linux F<a.out> executable format. Linux has used ELF for
-over twenty years.
-
-=item OpenBSD 6
-
-OpenBSD 6 still does not support returning C<pid>, C<gid>, or C<uid> with
-C<SA_SIGINFO>. Make sure to account for it.
-
-=item FreeBSD
-
-F<t/uni/overload.t>: Skip hanging test on FreeBSD.
-
-=item DragonFly BSD
-
-DragonFly BSD now has support for C<setproctitle()>.
-L<[perl #130068]|https://rt.perl.org/Public/Bug/Display.html?id=130068>.
-
-=back
-
-=head1 Internal Changes
-
-=over 4
-
-=item *
-
-A new API function L<C<sv_setpv_bufsize()>|perlapi/sv_setpv_bufsize>
-allows simultaneously setting the
-length and the allocated size of the buffer in an C<SV>, growing the
-buffer if necessary.
-
-=item *
-
-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 as some
-changes in the
-functionality of existing functions (see L<perlapi/Unicode Support> for
-more details):
-
-=over
-
-=item *
-
-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 *
-
-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 *
-
-Several new macros for analysing the validity of utf8 sequences. These
-are:
-
-L<C<UTF8_GOT_ABOVE_31_BIT>|perlapi/UTF8_GOT_ABOVE_31_BIT>
-L<C<UTF8_GOT_CONTINUATION>|perlapi/UTF8_GOT_CONTINUATION>
-L<C<UTF8_GOT_EMPTY>|perlapi/UTF8_GOT_EMPTY>
-L<C<UTF8_GOT_LONG>|perlapi/UTF8_GOT_LONG>
-L<C<UTF8_GOT_NONCHAR>|perlapi/UTF8_GOT_NONCHAR>
-L<C<UTF8_GOT_NON_CONTINUATION>|perlapi/UTF8_GOT_NON_CONTINUATION>
-L<C<UTF8_GOT_OVERFLOW>|perlapi/UTF8_GOT_OVERFLOW>
-L<C<UTF8_GOT_SHORT>|perlapi/UTF8_GOT_SHORT>
-L<C<UTF8_GOT_SUPER>|perlapi/UTF8_GOT_SUPER>
-L<C<UTF8_GOT_SURROGATE>|perlapi/UTF8_GOT_SURROGATE>
-L<C<UTF8_IS_INVARIANT>|perlapi/UTF8_IS_INVARIANT>
-L<C<UTF8_IS_NONCHAR>|perlapi/UTF8_IS_NONCHAR>
-L<C<UTF8_IS_SUPER>|perlapi/UTF8_IS_SUPER>
-L<C<UTF8_IS_SURROGATE>|perlapi/UTF8_IS_SURROGATE>
-L<C<UVCHR_IS_INVARIANT>|perlapi/UVCHR_IS_INVARIANT>
-L<C<isUTF8_CHAR_flags>|perlapi/isUTF8_CHAR_flags>
-L<C<isSTRICT_UTF8_CHAR>|perlapi/isSTRICT_UTF8_CHAR>
-L<C<isC9_STRICT_UTF8_CHAR>|perlapi/isC9_STRICT_UTF8_CHAR>
-
-=item *
-
-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>,
-L<C<is_strict_utf8_string_loc>|perlapi/is_strict_utf8_string_loc>,
-L<C<is_strict_utf8_string_loclen>|perlapi/is_strict_utf8_string_loclen>,
-
-L<C<is_c9strict_utf8_string>|perlapi/is_c9strict_utf8_string>,
-L<C<is_c9strict_utf8_string_loc>|perlapi/is_c9strict_utf8_string_loc>,
-L<C<is_c9strict_utf8_string_loclen>|perlapi/is_c9strict_utf8_string_loclen>,
-
-L<C<is_utf8_string_flags>|perlapi/is_utf8_string_flags>,
-L<C<is_utf8_string_loc_flags>|perlapi/is_utf8_string_loc_flags>,
-L<C<is_utf8_string_loclen_flags>|perlapi/is_utf8_string_loclen_flags>,
-
-L<C<is_utf8_fixed_width_buf_flags>|perlapi/is_utf8_fixed_width_buf_flags>,
-L<C<is_utf8_fixed_width_buf_loc_flags>|perlapi/is_utf8_fixed_width_buf_loc_flags>,
-L<C<is_utf8_fixed_width_buf_loclen_flags>|perlapi/is_utf8_fixed_width_buf_loclen_flags>.
-
-L<C<is_utf8_invariant_string>|perlapi/is_utf8_invariant_string>.
-L<C<is_utf8_valid_partial_char>|perlapi/is_utf8_valid_partial_char>.
-L<C<is_utf8_valid_partial_char_flags>|perlapi/is_utf8_valid_partial_char_flags>.
-
-=item *
-
-The functions L<C<utf8n_to_uvchr>|perlapi/utf8n_to_uvchr> and its
-derivatives have had several changes of behaviour.
-
-Calling them, while passing a string length of 0 is now asserted against
-in DEBUGGING builds, and otherwise, returns the Unicode REPLACEMENT
-CHARACTER. If you have nothing to decode, you shouldn't call the decode
-function.
-
-They now return the Unicode REPLACEMENT CHARACTER if called with UTF-8
-that has the overlong malformation and that malformation is allowed by
-the input parameters. This malformation is where the UTF-8 looks valid
-syntactically, but there is a shorter sequence that yields the same code
-point. This has been forbidden since Unicode version 3.1.
-
-They now accept an input
-flag to allow the overflow malformation. This malformation is when the
-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 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).
-
-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 *
-
-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. Use with caution.
-
-=item *
-
-A new function, L<C<utf8n_to_uvchr_error>|perlapi/utf8n_to_uvchr_error>,
-has been added for
-use by modules that need to know the details of UTF-8 malformations
-beyond pass/fail. Previously, the only ways to know why a sequence was
-ill-formed was to capture and parse the generated diagnostics or to do
-your own analysis.
-
-=item *
-
-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, 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 *
-
-Two new macros which return useful utf8 byte sequences:
-
-L<C<BOM_UTF8>|perlapi/BOM_UTF8>
-
-L<C<REPLACEMENT_CHARACTER_UTF8>|perlapi/REPLACEMENT_CHARACTER_UTF8>
-
-=back
-
-=item *
-
-Perl is now built with the C<PERL_OP_PARENT> compiler define enabled by
-default. To disable it, use the C<PERL_NO_OP_PARENT> compiler define.
-This flag alters how the C<op_sibling> field is used in C<OP> structures,
-and has been available optionally since perl 5.22.
-
-See L<perl5220delta/"Internal Changes"> for more details of what this
-build option does.
-
-=item *
-
-Three new ops, C<OP_ARGELEM>, C<OP_ARGDEFELEM>, and C<OP_ARGCHECK> have
-been added. These are intended principally to implement the individual
-elements of a subroutine signature, plus any overall checking required.
-
-=item *
-
-The C<OP_PUSHRE> op has been eliminated and the C<OP_SPLIT> op has been
-changed from class C<LISTOP> to C<PMOP>.
-
-Formerly the first child of a split would be a C<pushre>, which would have the
-C<split>'s regex attached to it. Now the regex is attached directly to the
-C<split> op, and the C<pushre> has been eliminated.
-
-=item *
-
-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
-allocated as an C<OP> or C<UNOP>; while C<op_class()> will return
-C<OPclass_BASEOP> or C<OPclass_UNOP> as appropriate.
-
-=item *
-
-All parts of the internals now agree that the C<sassign> op is a C<BINOP>;
-previously it was listed as a C<BASEOP> in F<regen/opcodes>, which meant
-that several parts of the internals had to be special-cased to accommodate
-it. This oddity's original motivation was to handle code like C<$x ||= 1>;
-that is now handled in a simpler way.
-
-=item *
-
-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 *
-
-The C<PADOFFSET> type has changed from being unsigned to signed, and
-several pad-related variables such as C<PL_padix> have changed from being
-of type C<I32> to type C<PADOFFSET>.
-
-=item *
-
-The C<DEBUGGING>-mode output for regex compilation and execution has been
-enhanced.
-
-=item *
-
-Several obscure SV flags have been eliminated, sometimes along with the
-macros which manipulate them: C<SVpbm_VALID>, C<SVpbm_TAIL>, C<SvTAIL_on>,
-C<SvTAIL_off>, C<SVrepl_EVAL>, C<SvEVALED>.
-
-=item *
-
-An OP C<op_private> flag has been eliminated: C<OPpRUNTIME>. This used to
-often get set on C<PMOP> ops, but had become meaningless over time.
-
-=back
-
-=head1 Selected Bug Fixes
-
-=over 4
-
-=item *
-
-Perl no longer panics when switching into some locales on machines with
-buggy C<strxfrm()> implementations in their F<libc>.
-L<[perl #121734]|https://rt.perl.org/Public/Bug/Display.html?id=121734>
-
-=item *
-
-C< $-{$name} > would leak an C<AV> on each access if the regular
-expression had no named captures. The same applies to access to any
-hash tied with L<Tie::Hash::NamedCapture> and C<< all =E<gt> 1 >>.
-L<[perl #130822]|https://rt.perl.org/Public/Bug/Display.html?id=130822>
-
-=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.
-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.
-L<[perl #129190]|https://rt.perl.org/Public/Bug/Display.html?id=129190>
-
-=item *
-
-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 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 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.
-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.
-L<[perl #129340]|https://rt.perl.org/Public/Bug/Display.html?id=129340>
-
-=item *
-
-Under C<use utf8>, the entire source code is now checked for being UTF-8
-well formed, not just quoted strings as before.
-L<[perl #126310]|https://rt.perl.org/Public/Bug/Display.html?id=126310>.
-
-=item *
-
-The range operator C<".."> on strings now handles its arguments correctly when in
-the scope of the L<< C<unicode_strings>|feature/"The 'unicode_strings' feature" >>
-feature. The previous behaviour was sufficiently unexpected that we believe no
-correct program could have made use of it.
-
-=item *
-
-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.
-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 of a single zero byte immediately beyond the end of an
-allocated buffer.
-L<[perl #129149]|https://rt.perl.org/Public/Bug/Display.html?id=129149>
-
-=item *
-
-Supplying a format's picture argument as part of the format argument list
-where the picture specifies modifying the argument could cause an
-access to the new freed compiled form.at.
-L<[perl #129125]|https://rt.perl.org/Public/Bug/Display.html?id=129125>
-
-=item *
-
-The L<sort()|perlfunc/sort> operator's built-in numeric comparison
-function didn't handle large integers that weren't exactly
-representable by a double. This now uses the same code used to
-implement the C<< E<lt>=E<gt> >> operator.
-L<[perl #130335]|https://rt.perl.org/Public/Bug/Display.html?id=130335>
-
-=item *
-
-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 *
-
-Fixed an assertion failure with C<chop> and C<chomp>, which
-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 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.
-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.
-L<[perl #130496]|https://rt.perl.org/Public/Bug/Display.html?id=130496>.
-
-=item *
-
-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 number about a misplaced C<"_">.
-L<[perl #70878]|https://rt.perl.org/Public/Bug/Display.html?id=70878>.
-
-=item *
-
-The C<tr///> parse code could be looking at uninitialized data after a
-perse error.
-L<[perl #129342]|https://rt.perl.org/Public/Bug/Display.html?id=129342>.
-
-=item *
-
-In a pattern match, a back-reference (C<\1>) to an unmatched capture could
-read back beyond the start of the string being matched.
-L<[perl #129377]|https://rt.perl.org/Public/Bug/Display.html?id=129377>.
-
-=item *
-
-C<use re 'strict'> is supposed to warn if you use a range (such as
-C</(?[ [ X-Y ] ])/>) 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 C<U+1D7E>.
-
-=item *
-
-A sub containing a "forward" declaration with the same name (I<e.g.>,
-C<sub c { sub c; }>) could sometimes crash or loop infinitely.
-L<[perl #129090]|https://rt.perl.org/Public/Bug/Display.html?id=129090>
-
-=item *
-
-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 *
-
-Previously, a shebang line like C<#!perl -i u> could be erroneously
-interpreted as requesting the C<-u> option. This has been fixed.
-L<[perl #129336]|https://rt.perl.org/Public/Bug/Display.html?id=129336>
-
-=item *
-
-The regex engine was previously producing incorrect results in some rare
-situations when backtracking past an alternation that matches only one
-thing; this
-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.
-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.
-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.
-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>.
-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.
-L<[perl #47047]|https://rt.perl.org/Public/Bug/Display.html?id=47047>
-
-=item *
-
-The use of C<splice> on arrays with non-existent elements could cause other
-operators to crash.
-L<[perl #129164]|https://rt.perl.org/Public/Bug/Display.html?id=129164>
-
-=item *
-
-A possible buffer overrun when a pattern contains a fixed utf8 substring.
-L<[perl #129012]|https://rt.perl.org/Public/Bug/Display.html?id=129012>
-
-=item *
-
-Fixed two possible use-after-free bugs in perl's lexer.
-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.
-L<[perl #129038]|https://rt.perl.org/Public/Bug/Display.html?id=129038>
-
-=item *
-
-Fixed a place where the regex parser was not setting the syntax error
-correctly on a syntactically incorrect pattern.
-L<[perl #129122]|https://rt.perl.org/Public/Bug/Display.html?id=129122>
-
-=item *
-
-The C<&.> operator (and the C<"&"> operator, when it treats its arguments as
-strings) were failing to append a trailing null byte if at least one string
-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.
-L<[perl #129287]|https://rt.perl.org/Public/Bug/Display.html?id=129287>
-
-=item *
-
-Avoid a heap-after-use error in the parser when creating an error messge
-for a syntactically invalid heredoc.
-L<[perl #128988]|https://rt.perl.org/Public/Bug/Display.html?id=128988>
-
-=item *
-
-Fix a segfault when run with C<-DC> options on DEBUGGING builds.
-L<[perl #129106]|https://rt.perl.org/Public/Bug/Display.html?id=129106>
-
-=item *
-
-Fixed the parser error handling in subroutine attributes for an
-'C<:attr(foo>' that does not have an ending 'C<")">'.
-
-=item *
-
-Fix the perl lexer to correctly handle a backslash as the last char in
-quoted-string context. This 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 *
-
-In the API function C<gv_fetchmethod_pvn_flags>, rework separator parsing
-to prevent possible string overrun with an invalid C<len> argument.
-L<[perl #129267]|https://rt.perl.org/Public/Bug/Display.html?id=129267>
-
-=item *
-
-Problems with in-place array sorts: code like C<@a = sort { ... } @a>,
-where the source and destination of the sort are the same plain array, are
-optimised to do less copying around. Two side-effects of this optimisation
-were that the contents of C<@a> as seen by sort routines were
-partially sorted; and under some circumstances accessing C<@a> during the
-sort could crash the interpreter. Both these issues have been fixed, and
-Sort functions see the original value of C<@a>.
-L<[perl #128340]|https://rt.perl.org/Public/Bug/Display.html?id=128340>
-
-=item *
-
-Non-ASCII string delimiters are now reported correctly in error messages
-for unterminated strings.
-L<[perl #128701]|https://rt.perl.org/Public/Bug/Display.html?id=128701>
-
-=item *
-
-C<pack("p", ...)> used to emit its warning ("Attempt to pack pointer to
-temporary value") erroneously in some cases, but has been fixed.
-
-=item *
-
-C<@DB::args> is now exempt from "used once" warnings. The warnings only
-occurred under B<-w>, because F<warnings.pm> itself uses C<@DB::args>
-multiple times.
-
-=item *
-
-The use of built-in arrays or hash slices in a double-quoted string no
-longer issues a warning ("Possible unintended interpolation...") if the
-variable has not been mentioned before. This affected code like
-C<qq|@DB::args|> and C<qq|@SIG{'CHLD', 'HUP'}|>. (The special variables
-C<@-> and C<@+> were already exempt from the warning.)
-
-=item *
-
-C<gethostent> and similar functions now perform a null check internally, to
-avoid crashing with the torsocks library. This was a regression from v5.22.
-L<[perl #128740]|https://rt.perl.org/Public/Bug/Display.html?id=128740>
-
-=item *
-
-C<defined *{'!'}>, C<defined *{'['}>, and C<defined *{'-'}> no longer leak
-memory if the typeglob in question has never been accessed before.
-
-=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.
-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 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".
-L<[perl #128843]|https://rt.perl.org/Public/Bug/Display.html?id=128843>
-L<[perl #128889]|https://rt.perl.org/Public/Bug/Display.html?id=128889>
-L<[perl #128890]|https://rt.perl.org/Public/Bug/Display.html?id=128890>
-L<[perl #128893]|https://rt.perl.org/Public/Bug/Display.html?id=128893>
-L<[perl #128909]|https://rt.perl.org/Public/Bug/Display.html?id=128909>
-L<[perl #128919]|https://rt.perl.org/Public/Bug/Display.html?id=128919>
-
-=item *
-
-A regression in v5.24 with C<tr/\N{U+...}/foo/> when the code point was between
-128 and 255 has been fixed.
-L<[perl #128734]|https://rt.perl.org/Public/Bug/Display.html?id=128734>.
-
-=item *
-
-Use of a string delimiter whose code point is above 2**31 now works
-correctly on platforms that allow this. Previously, certain characters,
-due to truncation, would be confused with other delimiter characters
-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.
-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.
-L<[perl #128951]|https://rt.perl.org/Public/Bug/Display.html?id=128951>
-
-=item *
-
-An assertion failure with C<%: = 0> has been fixed.
-L<[perl #128238]|https://rt.perl.org/Public/Bug/Display.html?id=128238>
-
-=item *
-
-In Perl 5.18, the parsing of C<"$foo::$bar"> was accidentally changed, such
-that it would be treated as C<$foo."::".$bar>. The previous behavior, which
-was to parse it as C<$foo:: . $bar>, has been restored.
-L<[perl #128478]|https://rt.perl.org/Public/Bug/Display.html?id=128478>
-
-=item *
-
-Since Perl 5.20, line numbers have been off by one when perl is invoked with
-the B<-x> switch. This has been fixed.
-L<[perl #128508]|https://rt.perl.org/Public/Bug/Display.html?id=128508>
-
-=item *
-
-Vivifying a subroutine stub in a deleted stash (I<e.g.>,
-C<delete $My::{"Foo::"}; \&My::Foo::foo>) no longer crashes. It had begun
-crashing in Perl 5.18.
-L<[perl #128532]|https://rt.perl.org/Public/Bug/Display.html?id=128532>
-
-=item *
-
-Some obscure cases of subroutines and file handles being freed at the same time
-could result in crashes, but have been fixed. The crash was introduced in Perl
-5.22.
-L<[perl #128597]|https://rt.perl.org/Public/Bug/Display.html?id=128597>
-
-=item *
-
-Code that looks for a variable name associated with an uninitialized value
-could cause an assertion failure in cases where magic is involved, such as
-C<$ISA[0][0]>. This has now been fixed.
-L<[perl #128253]|https://rt.perl.org/Public/Bug/Display.html?id=128253>
-
-=item *
-
-A crash caused by code generating the warning "Subroutine STASH::NAME
-redefined" in cases such as C<sub P::f{} undef *P::; *P::f =sub{};> has been
-fixed. In these cases, where the STASH is missing, the warning will now appear
-as "Subroutine NAME redefined".
-L<[perl #128257]|https://rt.perl.org/Public/Bug/Display.html?id=128257>
-
-=item *
-
-Fixed an assertion triggered by some code that handles deprecated behavior in
-formats, I<e.g.>, in cases like this:
-
- format STDOUT =
- @
- 0"$x"
-
-L<[perl #128255]|https://rt.perl.org/Public/Bug/Display.html?id=128255>
-
-=item *
-
-A possible divide by zero in string transformation code on Windows has been
-avoided, fixing a crash when collating an empty string.
-L<[perl #128618]|https://rt.perl.org/Public/Bug/Display.html?id=128618>
-
-=item *
-
-Some regular expression parsing glitches could lead to assertion failures with
-regular expressions such as C</(?E<lt>=/> and C</(?E<lt>!/>. This has now been fixed.
-L<[perl #128170]|https://rt.perl.org/Public/Bug/Display.html?id=128170>
-
-=item *
-
-C< until ($x = 1) { ... } > and C< ... until $x = 1 > now properly
-warn when syntax warnings are enabled.
-L<[perl #127333]|https://rt.perl.org/Public/Bug/Display.html?id=127333>
-
-=item *
-
-socket() now leaves the error code returned by the system in C<$!> on
-failure.
-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.
-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 C<$_>, rather than
-C<require "">.
-L<[perl #128307]|https://rt.perl.org/Public/Bug/Display.html?id=128307>
-
-=item *
-
-Scalar C<keys %hash> can now be assigned to consistently in all scalar
-lvalue contexts. Previously it worked for some contexts but not others.
-
-=item *
-
-List assignment to C<vec> or C<substr> with an array or hash for its first
-argument used to result in crashes or "Can't coerce" error messages at run
-time, unlike scalar assignment, which would give an error at compile time.
-List assignment now gives a compile-time error, too.
-L<[perl #128260]|https://rt.perl.org/Public/Bug/Display.html?id=128260>
-
-=item *
-
-Expressions containing an C<&&> or C<||> operator (or their synonyms C<and>
-and C<or>) were being compiled incorrectly in some cases. If the left-hand
-side consisted of either a negated bareword constant or a negated C<do {}>
-block containing a constant expression, and the right-hand side consisted of
-a negated non-foldable expression, one of the negations was effectively
-ignored. The same was true of C<if> and C<unless> statement modifiers,
-though with the left-hand and right-hand sides swapped. This long-standing
-bug has now been fixed.
-L<[perl #127952]|https://rt.perl.org/Public/Bug/Display.html?id=127952>
-
-=item *
-
-C<reset> with an argument no longer crashes when encountering stash entries
-other than globs.
-L<[perl #128106]|https://rt.perl.org/Public/Bug/Display.html?id=128106>
-
-=item *
-
-Assignment of hashes to, and deletion of, typeglobs named C<*::::::> no
-longer causes crashes.
-L<[perl #128086]|https://rt.perl.org/Public/Bug/Display.html?id=128086>
-
-=item *
-
-Perl wasn't correctly handling true/false values in the LHS of a list
-assign; specifically the truth values returned by boolean operators.
-This could trigger an assertion failure in something like the following:
-
- for ($x > $y) {
- ($_, ...) = (...); # here $_ is aliased to a truth value
- }
-
-This was a regression from v5.24.
-L<[perl #129991]|https://rt.perl.org/Public/Bug/Display.html?id=129991>
-
-=item *
-
-Assertion failure with user-defined Unicode-like properties.
-L<[perl #130010]|https://rt.perl.org/Public/Bug/Display.html?id=130010>
-
-=item *
-
-Fix error message for unclosed C<\N{> in a regex. An unclosed C<\N{>
-could give the wrong error message:
-C<"\N{NAME} must be resolved by the lexer">.
-
-=item *
-
-List assignment in list context where the LHS contained aggregates and
-where there were not enough RHS elements, used to skip scalar lvalues.
-Previously, C<(($a,$b,@c,$d) = (1))> in list context returned C<($a)>; now
-it returns C<($a,$b,$d)>. C<(($a,$b,$c) = (1))> is unchanged: it still
-returns C<($a,$b,$c)>. This can be seen in the following:
-
- sub inc { $_++ for @_ }
- inc(($a,$b,@c,$d) = (10))
-
-Formerly, the values of C<($a,$b,$d)> would be left as C<(11,undef,undef)>;
-now they are C<(11,1,1)>.
-
-=item *
-
-Code like this: C</(?{ s!!! })/> could trigger infinite recursion on the C
-stack (not the normal perl stack) when the last successful pattern in
-scope is itself. We avoid the segfault by simply forbidding the use of
-the empty pattern when it would resolve to the currently executing
-pattern.
-L<[perl #129903]|https://rt.perl.org/Public/Bug/Display.html?id=129903>
-
-=item *
-
-Avoid reading beyond the end of the line buffer in perl's lexer when
-there's a short UTF-8 character at the end.
-L<[perl #128997]|https://rt.perl.org/Public/Bug/Display.html?id=128997>
-
-=item *
-
-Alternations in regular expressions were sometimes failing to match
-a utf8 string against a utf8 alternate.
-L<[perl #129950]|https://rt.perl.org/Public/Bug/Display.html?id=129950>
-
-=item *
-
-Make C<do "a\0b"> fail silently (and return C<undef> and set C<$!>)
-instead of throwing an error.
-L<[perl #129928]|https://rt.perl.org/Public/Bug/Display.html?id=129928>
-
-=item *
-
-C<chdir> with no argument didn't ensure that there was stack space
-available for returning its result.
-L<[perl #129130]|https://rt.perl.org/Public/Bug/Display.html?id=129130>
-
-=item *
-
-All error messages related to C<do> now refer to C<do>; some formerly
-claimed to be from C<require> instead.
-
-=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 *
-
-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 concatenation
-overloading to string overloading if C<< $scalar-E<gt>$* >> returns an
-overloaded object, bringing it into consistency with C<$$scalar>.
-
-=item *
-
-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 *
-
-C<do> or C<require> with an argument which is 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 *
-
-Improve the error message for a missing C<tie()> package/method. This
-brings the error messages in line with the ones used for normal method
-calls.
-
-=item *
-
-Parsing bad POSIX charclasses no longer leaks memory.
-L<[perl #128313]|https://rt.perl.org/Public/Bug/Display.html?id=128313>
-
-=back
-
-=head1 Known Problems
-
-=over 4
-
-=item *
-
-G++ 6 handles subnormal (denormal) floating point values differently
-than gcc 6 or g++ 5 resulting in "flush-to-zero". The end result is
-that if you specify very small values using the hexadecimal floating
-point format, like C<0x1.fffffffffffffp-1022>, they become zeros.
-L<[perl #131388]|https://rt.perl.org/Ticket/Display.html?id=131388>
-
-=back
-
-=head1 Errata From Previous Releases
-
-=over 4
-
-=item *
-
-Fixed issues with recursive regexes. The behavior was fixed in Perl 5.24.
-L<[perl #126182]|https://rt.perl.org/Public/Bug/Display.html?id=126182>
-
-=back
-
-=head1 Obituary
-
-Jon Portnoy (AVENJ), a prolific Perl author and admired Gentoo community
-member, has passed away on August 10, 2016. He will be remembered and
-missed by all those who he came in contact with, and enriched with his
-intellect, wit, and spirit.
-
-It is with great sadness that we also note Kip Hampton's passing. Probably
-best known as the author of the Perl & XML column on XML.com, he was a
-core contributor to AxKit, an XML server platform that became an Apache
-Foundation project. He was a frequent speaker in the early days at
-OSCON, and most recently at YAPC::NA in Madison. He was frequently on
-irc.perl.org as ubu, generally in the #axkit-dahut community, the
-group responsible for YAPC::NA Asheville in 2011.
-
-Kip and his constant contributions to the community will be greatly
-missed.
-
-=head1 Acknowledgements