[ this is a template for a new perldelta file. Any text flagged as XXX needs
to be processed before release. ]
-perldelta - what is new for perl v5.25.5
+perldelta - what is new for perl v5.25.9
=head1 DESCRIPTION
-This document describes differences between the 5.25.4 release and the 5.25.5
+This document describes differences between the 5.25.8 release and the 5.25.9
release.
-If you are upgrading from an earlier release such as 5.25.3, first read
-L<perl5254delta>, which describes differences between 5.25.3 and 5.25.4.
+If you are upgrading from an earlier release such as 5.25.7, first read
+L<perl5258delta>, which describes differences between 5.25.7 and 5.25.8.
=head1 Notice
enhancements. Particularly prominent performance optimisations could go
here, but most should go in the L</Performance Enhancements> section.
-[ List each enhancement as a =head2 entry ]
+=head2 New regular expression modifier C</xx>
+
+Specifying two C<x> characters to modify a regular expression pattern
+does everything that a single one does, but additionally TAB and SPACE
+characters within a bracketed character class are generally ignored and
+can be added to improve readability, like
+S<C</[ ^ A-Z d-f p-x ]/xx>>. Details are at
+L<perlre/E<sol>x and E<sol>xx>.
=head1 Security
vulnerabilities closed should be noted here rather than in the
L</Selected Bug Fixes> section.
-=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
-in that example.
+[ List each security issue as a =head2 entry ]
=head1 Incompatible Changes
=head1 Deprecations
-XXX Any deprecated features, syntax, modules etc. should be listed here.
+=head2 String delimiters that aren't stand-alone graphemes are now
+deprecated
+
+In order for Perl to eventually allow string delimiters to be Unicode
+grapheme clusters (which look like a single character, but may be
+a sequence of several ones), we have to stop allowing a single char
+delimiter that isn't a grapheme by itself. These are unlikely to exist
+in actual code, as they would typically display as attached to the
+character in front of them.
=head2 Module removals
=item *
-XXX
+A hash in boolean context is now sometimes faster, e.g.
+
+ if (!%h) { ... }
+
+This was already special-cased, but some cases were missed, and even the
+ones which weren't have been improved.
=back
=item *
-L<Filter::Simple> has been upgraded from version 0.92 to 0.93.
+L<XXX> has been upgraded from version A.xx to B.yy.
+
+=item *
+
+L<re> has been upgraded from version 0.33 to 0.34;
+
+This adds support for the new L<C</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 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<B::Xref> has been upgraded from version 1.05 to 1.06.
-It no longer treats C<no MyFilter> immediately following C<use MyFilter> as
-end-of-file. [perl #107726]
+=item *
+
+L<Compress::Raw::Bzip2> has been upgraded from version 2.069 to 2.070.
=item *
-L<Thread::Semaphore> has been upgraded from 2.12 to 2.13.
+L<Compress::Raw::Zlib> has been upgraded from version 2.069 to 2.070.
+
+=item *
+
+L<DB_File> has been upgraded from version 1.838 to 1.840.
+
+=item *
+
+L<Devel::SelfStubber> has been upgraded from version 1.05 to 1.06.
+
+=item *
+
+L<diagnostics> has been upgraded from version 1.35 to 1.36.
+
+=item *
-Added the C<down_timed> method.
+L<DynaLoader> has been upgraded from version 1.40 to 1.41.
+
+=item *
+
+L<Errno> has been upgraded from version 1.27 to 1.28.
+
+=item *
+
+L<ExtUtils::Embed> has been upgraded from version 1.33 to 1.34.
+
+=item *
+
+L<I18N::LangTags> has been upgraded from version 0.41 to 0.42.
+
+=item *
+
+L<lib> has been upgraded from version 0.63 to 0.64.
+
+=item *
+
+L<Module::CoreList> has been upgraded from version 5.20161220 to 5.20170120.
+
+=item *
+
+L<OS2::Process> has been upgraded from version 1.11 to 1.12.
+
+=item *
+
+L<perl5db.pl> has been upgraded from version 1.50 to 1.51.
+
+=item *
+
+L<Storable> has been upgraded from version 2.59 to 2.61.
+
+=item *
+
+L<Symbol> has been upgraded from version 1.07 to 1.08.
+
+=item *
+
+L<Term::ReadLine> has been upgraded from version 1.15 to 1.16.
+
+=item *
+
+L<Test> has been upgraded from version 1.29 to 1.30.
+
+=item *
+
+L<threads::shared> has been upgraded from version 1.52 to 1.53.
+
+=item *
+
+L<Unicode::UCD> has been upgraded from version 0.67 to 0.68.
+
+=item *
+
+L<VMS::DCLsym> has been upgraded from version 1.07 to 1.08.
+
+=item *
+
+L<XSLoader> has been upgraded from version 0.24 to 0.26.
+
+=item *
+
+L<CPAN> has been upgraded from version 2.14_01 to 2.16.
=back
However, any changes to F<pod/perldiag.pod> should go in the L</Diagnostics>
section.
-=head3 L<perlinterp>
+=head3 L<XXX>
=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.
+XXX Description of the change here
=back
=head2 Changes to Existing Diagnostics
-XXX Changes (i.e. rewording) of diagnostic messages go here
+As of Perl 5.25.9, all new deprecations will come with a version in
+which the feature will disappear. And with a few exceptions, most
+existing deprecations will state when they'll disappear. As such, most
+deprecation messages have changed.
=over 4
=item *
-XXX Describe change here
+Attribute "locked" is deprecated, and will disappear in Perl 5.28
+
+=item *
+
+Attribute "unique" is deprecated, and will disappear in Perl 5.28
+
+=item *
+
+"\c%c" is more clearly written simply as "%s". This will be a fatal error
+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
+
+=item *
+
+Opening filehandle %s also as a directory. This will be a fatal
+error 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
+
+=item *
+
+Unescaped left brace in regex is deprecated here (and will be fatal
+in Perl 5.30), passed through in regex; marked by S<<-- HERE> in m/%s/
+
+=item *
+
+Unknown charname '' is deprecated. Its use will be fatal in Perl 5.28
+
+=item *
+
+Use of bare << to mean <<"" is deprecated. Its use will be fatal in Perl 5.28
+
+=item *
+
+Use of code point 0x%s is deprecated; the permissible max is 0x%s.
+This 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
+
+=item *
+
+Use of inherited AUTOLOAD for non-method %s() is deprecated. This
+will be fatal in Perl 5.28
+
+=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
=back
=item *
-XXX
+The C<dtrace> build process has further changes:
+
+=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 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 libelf to the build on FreeBSD 10.x, since dtrace adds references
+to libelf symbols.
+
+=item *
+
+Generate a dummy 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
+
+[perl #130108]
+
+=item *
+
+You can now disable perl's use of the PERL_HASH_SEED and
+PERL_PERTURB_KEYS environment variables by configureing perl with
+C<-Accflags=NO_PERL_HASH_ENV>.
+
+=item *
+
+You can now disable perl's use of the PERL_HASH_SEED_DEBUG environment
+variable by configuring perl with
+C<-Accflags=-DNO_PERL_HASH_SEED_DEBUG>.
=back
=over 4
-=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 *
-
-Remove some VMS-specific hacks from C<showlex.t>. These were added 15 years
-ago, and are no longer necessary for any VMS version now supported.
-
-=back
-
-=back
-
-=over 4
-
-=item Win32
-
-=over 4
-
-=item *
-
-Tweaks for Win32 VC vs GCC detection makefile code. This fixes issue that CCHOME
-depends on CCTYPE, which in auto detect mode is set after CCHOME, so CCHOME uses
-the uninit CCTYPE var. Also fix else vs .ELSE in makefile.mk
+=item XXX-some-platform
-=back
+XXX
=back
=item *
-Several macros and functions have been added to the public API for
-dealing with Unicode and UTF-8-encoded strings. See
-L<perlapi/Unicode Support>.
+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 ther use
+now raises a deprecation warning. Details are at
+L<perlapi/Character classification>.
=item *
-Use C<my_strlcat()> in C<locale.c>. While C<strcat()> is safe in this context,
-some compilers were optimizing this to C<strcpy()> causing a porting test to
-fail that looks for unsafe code. Rather than fighting this, we just use
-C<my_strlcat()> instead.
-
-=back
-
-=head1 Selected Bug Fixes
-
-XXX Important bug fixes in the core language are summarized here. Bug fixes in
-files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
-
-[ List each fix as a =item entry ]
-
-=over 4
+Calling macros like C<isALPHA_utf8> on malformed UTF-8 have issued a
+deprecation warning since Perl v5.18. They now die.
+Similarly, macros like C<toLOWER_utf8> on malformed UTF-8 now die.
=item *
-Invalid assignments to a reference constructor (e.g., C<\eval=time>) could
-sometimes crash in addition to giving a syntax error. [perl #125679]
+Calling the functions C<utf8n_to_uvchr> and its derivatives, 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.
=item *
-The parser could sometimes crash if a bareword came after C<evalbytes>.
-[perl #129196]
+The functions C<utf8n_to_uvchr> and its derivatives 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.
=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 *
+The functions C<utf8n_to_uvchr> and its derivatives 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 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).
-A sub containing with a "forward" declaration with the same name (e.g.,
-C<sub c { sub c; }>) could sometimes crash or loop infinitely. [perl
-#129090]
+=back
-=item *
+=head1 Selected Bug Fixes
-The use of C<splice> on arrays with nonexistent elements could cause other
-operators to crash. [perl #129164]
+XXX Important bug fixes in the core language are summarized here. Bug fixes in
+files in F<ext/> and F<lib/> are best summarized in L</Modules and Pragmata>.
-=item *
+[ List each fix as a =item entry ]
-Fixed case where C<re_untuit_start> will overshoot the length of a utf8
-string. [perl #129012]
+=over 4
=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]
+Under C<use utf8>, the entire Perl program is now checked that the UTF-8
+is wellformed. This resolves [perl #126310].
=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]
+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 *
-Fixed a crash with C<s///l> where it thought it was dealing with UTF-8
-when it wasn't. [perl #129038]
+The S<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]
=item *
-Fixed place where regex was not setting the syntax error correctly.
-[perl #129122]
+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]
=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 with which he came in contact and enriched with his
-intellect, wit, and spirit.
+XXX If any significant core contributor has died, we've added a short obituary
+here.
=head1 Acknowledgements
XXX Generate this with:
- perl Porting/acknowledgements.pl v5.25.4..HEAD
+ perl Porting/acknowledgements.pl v5.25.5..HEAD
=head1 Reporting Bugs
https://perl5.git.perl.org / perl5.git / blobdiff