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diff --git a/Master/tlpkg/tlperl/lib/pods/perl5110delta.pod b/Master/tlpkg/tlperl/lib/pods/perl5110delta.pod deleted file mode 100644 index 7ceb174a09c..00000000000 --- a/Master/tlpkg/tlperl/lib/pods/perl5110delta.pod +++ /dev/null @@ -1,1624 +0,0 @@ -=encoding utf8 - -=head1 NAME - -perl5110delta - what is new for perl v5.11.0 - -=head1 DESCRIPTION - -This document describes differences between the 5.10.0 release and -the 5.11.0 development release. - -=head1 Incompatible Changes - -=head2 Unicode interpretation of \w, \d, \s, and the POSIX character classes redefined. - -Previous versions of Perl tried to map POSIX style character class definitions onto -Unicode property names so that patterns would "dwim" when matches were made against latin-1 or -unicode strings. This proved to be a mistake, breaking character class negation, causing -forward compatibility problems (as Unicode keeps updating their property definitions and adding -new characters), and other problems. - -Therefore we have now defined a new set of artificial "unicode" property names which will be -used to do unicode matching of patterns using POSIX style character classes and perl short-form -escape character classes like \w and \d. - -The key change here is that \d will no longer match every digit in the unicode standard -(there are thousands) nor will \w match every word character in the standard, instead they -will match precisely their POSIX or Perl definition. - -Those needing to match based on Unicode properties can continue to do so by using the \p{} syntax -to match whichever property they like, including the new artificial definitions. - -B<NOTE:> This is a backwards incompatible no-warning change in behaviour. If you are upgrading -and you process large volumes of text look for POSIX and Perl style character classes and -change them to the relevant property name (by removing the word 'Posix' from the current name). - -The following table maps the POSIX character class names, the escapes and the old and new -Unicode property mappings: - - POSIX Esc Class New-Property ! Old-Property - ----------------------------------------------+------------- - alnum [0-9A-Za-z] IsPosixAlnum ! IsAlnum - alpha [A-Za-z] IsPosixAlpha ! IsAlpha - ascii [\000-\177] IsASCII = IsASCII - blank [\011 ] IsPosixBlank ! - cntrl [\0-\37\177] IsPosixCntrl ! IsCntrl - digit \d [0-9] IsPosixDigit ! IsDigit - graph [!-~] IsPosixGraph ! IsGraph - lower [a-z] IsPosixLower ! IsLower - print [ -~] IsPosixPrint ! IsPrint - punct [!-/:-@[-`{-~] IsPosixPunct ! IsPunct - space [\11-\15 ] IsPosixSpace ! IsSpace - \s [\11\12\14\15 ] IsPerlSpace ! IsSpacePerl - upper [A-Z] IsPosixUpper ! IsUpper - word \w [0-9A-Z_a-z] IsPerlWord ! IsWord - xdigit [0-9A-Fa-f] IsXDigit = IsXDigit - -If you wish to build perl with the old mapping you may do so by setting - - #define PERL_LEGACY_UNICODE_CHARCLASS_MAPPINGS 1 - -in regcomp.h, and then setting - - PERL_TEST_LEGACY_POSIX_CC - -to true your environment when testing. - - -=head2 @INC reorganization - -In @INC, ARCHLIB and PRIVLIB now occur after after the current version's -site_perl and vendor_perl. - -=head2 Switch statement changes - -The handling of complex expressions by the C<given>/C<when> switch -statement has been enhanced. These enhancements are also available in -5.10.1 and subsequent 5.10 releases. There are two new cases where C<when> now -interprets its argument as a boolean, instead of an expression to be used -in a smart match: - -=over 4 - -=item flip-flop operators - -The C<..> and C<...> flip-flop operators are now evaluated in boolean -context, following their usual semantics; see L<perlop/"Range Operators">. - -Note that, as in perl 5.10.0, C<when (1..10)> will not work to test -whether a given value is an integer between 1 and 10; you should use -C<when ([1..10])> instead (note the array reference). - -However, contrary to 5.10.0, evaluating the flip-flop operators in boolean -context ensures it can now be useful in a C<when()>, notably for -implementing bistable conditions, like in: - - when (/^=begin/ .. /^=end/) { - # do something - } - -=item defined-or operator - -A compound expression involving the defined-or operator, as in -C<when (expr1 // expr2)>, will be treated as boolean if the first -expression is boolean. (This just extends the existing rule that applies -to the regular or operator, as in C<when (expr1 || expr2)>.) - -=back - -The next section details more changes brought to the semantics to -the smart match operator, that naturally also modify the behaviour -of the switch statements where smart matching is implicitly used. -These changers were also made for the 5.10.1 release, and will remain in -subsequent 5.10 releases. - -=head2 Smart match changes - -=head3 Changes to type-based dispatch - -The smart match operator C<~~> is no longer commutative. The behaviour of -a smart match now depends primarily on the type of its right hand -argument. Moreover, its semantics have been adjusted for greater -consistency or usefulness in several cases. While the general backwards -compatibility is maintained, several changes must be noted: - -=over 4 - -=item * - -Code references with an empty prototype are no longer treated specially. -They are passed an argument like the other code references (even if they -choose to ignore it). - -=item * - -C<%hash ~~ sub {}> and C<@array ~~ sub {}> now test that the subroutine -returns a true value for each key of the hash (or element of the -array), instead of passing the whole hash or array as a reference to -the subroutine. - -=item * - -Due to the commutativity breakage, code references are no longer -treated specially when appearing on the left of the C<~~> operator, -but like any vulgar scalar. - -=item * - -C<undef ~~ %hash> is always false (since C<undef> can't be a key in a -hash). No implicit conversion to C<""> is done (as was the case in perl -5.10.0). - -=item * - -C<$scalar ~~ @array> now always distributes the smart match across the -elements of the array. It's true if one element in @array verifies -C<$scalar ~~ $element>. This is a generalization of the old behaviour -that tested whether the array contained the scalar. - -=back - -The full dispatch table for the smart match operator is given in -L<perlsyn/"Smart matching in detail">. - -=head3 Smart match and overloading - -According to the rule of dispatch based on the rightmost argument type, -when an object overloading C<~~> appears on the right side of the -operator, the overload routine will always be called (with a 3rd argument -set to a true value, see L<overload>.) However, when the object will -appear on the left, the overload routine will be called only when the -rightmost argument is a simple scalar. This way distributivity of smart match -across arrays is not broken, as well as the other behaviours with complex -types (coderefs, hashes, regexes). Thus, writers of overloading routines -for smart match mostly need to worry only with comparing against a scalar, -and possibly with stringification overloading; the other common cases -will be automatically handled consistently. - -C<~~> will now refuse to work on objects that do not overload it (in order -to avoid relying on the object's underlying structure). (However, if the -object overloads the stringification or the numification operators, and -if overload fallback is active, it will be used instead, as usual.) - -=head2 Labels can't be keywords - -Labels used as targets for the C<goto>, C<last>, C<next> or C<redo> -statements cannot be keywords anymore. This restriction will prevent -potential confusion between the C<goto LABEL> and C<goto EXPR> syntaxes: -for example, a statement like C<goto print> would jump to a label whose -name would be the return value of C<print()>, (usually 1), instead of a -label named C<print>. Moreover, the other control flow statements -would just ignore any keyword passed to them as a label name. Since -such labels cannot be defined anymore, this kind of error will be -avoided. - -=head2 Other incompatible changes - -=over 4 - -=item * - -The semantics of C<use feature :5.10*> have changed slightly. -See L<"Modules and Pragmata"> for more information. - -=item * - -It is now a run-time error to use the smart match operator C<~~> -with an object that has no overload defined for it. (This way -C<~~> will not break encapsulation by matching against the -object's internal representation as a reference.) - -=item * - -The version control system used for the development of the perl -interpreter has been switched from Perforce to git. This is mainly an -internal issue that only affects people actively working on the perl core; -but it may have minor external visibility, for example in some of details -of the output of C<perl -V>. See L<perlrepository> for more information. - -=item * - -The internal structure of the C<ext/> directory in the perl source has -been reorganised. In general, a module C<Foo::Bar> whose source was -stored under F<ext/Foo/Bar/> is now located under F<ext/Foo-Bar/>. Also, -nearly all dual-life modules have been moved from F<lib/> to F<ext/>. This -is purely a source tarball change, and should make no difference to the -compilation or installation of perl, unless you have a very customised build -process that explicitly relies on this structure, or which hard-codes the -C<nonxs_ext> F<Configure> parameter. Specifically, this change does not by -default alter the location of any files in the final installation. - -=item * - -As part of the C<Test::Harness> 2.x to 3.x upgrade, the experimental -C<Test::Harness::Straps> module has been removed. -See L</"Updated Modules"> for more details. - -=item * - -As part of the C<ExtUtils::MakeMaker> upgrade, the -C<ExtUtils::MakeMaker::bytes> and C<ExtUtils::MakeMaker::vmsish> modules -have been removed from this distribution. - -=item * - -C<Module::CoreList> no longer contains the C<%:patchlevel> hash. - -=item * - -This one is actually a change introduced in 5.10.0, but it was missed -from that release's perldelta, so it is mentioned here instead. - -A bugfix related to the handling of the C</m> modifier and C<qr> resulted -in a change of behaviour between 5.8.x and 5.10.0: - - # matches in 5.8.x, doesn't match in 5.10.0 - $re = qr/^bar/; "foo\nbar" =~ /$re/m; - -=item * - -C<length undef> now returns undef. - -=item * - -Unsupported private C API functions are now declared "static" to prevent -leakage to Perl's public API. - -=item * - -To support the bootstrapping process, F<miniperl> no longer builds with -UTF-8 support in the regexp engine. - -This allows a build to complete with PERL_UNICODE set and a UTF-8 locale. -Without this there's a bootstrapping problem, as miniperl can't load the UTF-8 -components of the regexp engine, because they're not yet built. - -=item * - -F<miniperl>'s @INC is now restricted to just -I..., the split of $ENV{PERL5LIB}, and "." - -=item * - -A space or a newline is now required after a C<"#line XXX"> directive. - -=item * - -Tied filehandles now have an additional method EOF which provides the EOF type - -=item * - -To better match all other flow control statements, C<foreach> may no longer be used as an attribute. - -=back - -=head1 Core Enhancements - -=head2 Unicode Character Database 5.1.0 - -The copy of the Unicode Character Database included in Perl 5.11.0 has -been updated to 5.1.0 from 5.0.0. See -L<http://www.unicode.org/versions/Unicode5.1.0/#Notable_Changes> for the -notable changes. - -=head2 A proper interface for pluggable Method Resolution Orders - -As of Perl 5.11.0 there is a new interface for plugging and using method -resolution orders other than the default (linear depth first search). -The C3 method resolution order added in 5.10.0 has been re-implemented as -a plugin, without changing its Perl-space interface. See L<perlmroapi> for -more information. - -=head2 The C<overloading> pragma - -This pragma allows you to lexically disable or enable overloading -for some or all operations. (Yuval Kogman) - -=head2 C<\N> regex escape - -A new regex escape has been added, C<\N>. It will match any character that -is not a newline, independently from the presence or absence of the single -line match modifier C</s>. (If C<\N> is followed by an opening brace and -by a letter, perl will still assume that a Unicode character name is -coming, so compatibility is preserved.) (Rafael Garcia-Suarez) - -=head2 Implicit strictures - -Using the C<use VERSION> syntax with a version number greater or equal -to 5.11.0 will also lexically enable strictures just like C<use strict> -would do (in addition to enabling features.) So, the following: - - use 5.11.0; - -will now imply: - - use strict; - use feature ':5.11'; - -=head2 Parallel tests - -The core distribution can now run its regression tests in parallel on -Unix-like platforms. Instead of running C<make test>, set C<TEST_JOBS> in -your environment to the number of tests to run in parallel, and run -C<make test_harness>. On a Bourne-like shell, this can be done as - - TEST_JOBS=3 make test_harness # Run 3 tests in parallel - -An environment variable is used, rather than parallel make itself, because -L<TAP::Harness> needs to be able to schedule individual non-conflicting test -scripts itself, and there is no standard interface to C<make> utilities to -interact with their job schedulers. - -Note that currently some test scripts may fail when run in parallel (most -notably C<ext/IO/t/io_dir.t>). If necessary run just the failing scripts -again sequentially and see if the failures go away. - -=head2 The C<...> operator - -A new operator, C<...>, nicknamed the Yada Yada operator, has been added. -It is intended to mark placeholder code, that is not yet implemented. -See L<perlop/"Yada Yada Operator">. (chromatic) - -=head2 DTrace support - -Some support for DTrace has been added. See "DTrace support" in F<INSTALL>. - -=head2 Support for C<configure_requires> in CPAN module metadata - -Both C<CPAN> and C<CPANPLUS> now support the C<configure_requires> keyword -in the F<META.yml> metadata file included in most recent CPAN distributions. -This allows distribution authors to specify configuration prerequisites that -must be installed before running F<Makefile.PL> or F<Build.PL>. - -See the documentation for C<ExtUtils::MakeMaker> or C<Module::Build> for more -on how to specify C<configure_requires> when creating a distribution for CPAN. - -=head2 C<each> is now more flexible - -The C<each> function can now operate on arrays. - -=head2 Y2038 compliance - -Perl's core time-related functions are now Y2038 compliant. (With 29 -years to spare!) - -=head2 C<$,> flexibility - -The variable C<$,> may now be tied. - -=head2 // in where clauses - -// now behaves like || in when clauses - -=head2 Enabling warnings from your shell environment - -You can now set C<-W> from the C<PERL5OPT> environment variable - -=head2 C<delete local> - -C<delete local> now allows you to locally delete a hash entry. - -=head2 New support for Abstract namespace sockets - -Abstract namespace sockets are Linux-specific socket type that live in -AF_UNIX family, slightly abusing it to be able to use arbitrary -character arrays as addresses: They start with nul byte and are not -terminated by nul byte, but with the length passed to the socket() -system call. - -=head1 Modules and Pragmata - -=head2 Dual-lifed modules moved - -Dual-lifed modules maintained primarily in the Perl core now live in dist/. -Dual-lifed modules maintained primarily on CPAN now live in cpan/ - -In previous releases of Perl, it was customary to enumerate all module -changes in this section of the C<perldelta> file. From 5.11.0 forward -only notable updates (such as new or deprecated modules ) will be -listed in this section. For a complete reference to the versions of -modules shipped in a given release of perl, please see L<Module::CoreList>. - -=head2 New Modules and Pragmata - -=over 4 - -=item C<autodie> - -This is a new lexically-scoped alternative for the C<Fatal> module. -The bundled version is 2.06_01. Note that in this release, using a string -eval when C<autodie> is in effect can cause the autodie behaviour to leak -into the surrounding scope. See L<autodie/"BUGS"> for more details. - -=item C<Compress::Raw::Bzip2> - -This has been added to the core (version 2.020). - -=item C<parent> - -This pragma establishes an ISA relationship with base classes at compile -time. It provides the key feature of C<base> without the feature creep. - -=item C<Parse::CPAN::Meta> - -This has been added to the core (version 1.39). - -=back - -=head2 Pragmata Changes - -=over 4 - -=item C<overloading> - -See L</"The C<overloading> pragma"> above. - -=item C<attrs> - -The C<attrs> pragma has been removed. It had been marked as deprecated since -5.6.0. - -=item C<charnames> - -The Unicode F<NameAliases.txt> database file has been added. This has the -effect of adding some extra C<\N> character names that formerly wouldn't -have been recognised; for example, C<"\N{LATIN CAPITAL LETTER GHA}">. - -=item C<feature> - -The meaning of the C<:5.10> and C<:5.10.X> feature bundles has -changed slightly. The last component, if any (i.e. C<X>) is simply ignored. -This is predicated on the assumption that new features will not, in -general, be added to maintenance releases. So C<:5.10> and C<:5.10.X> -have identical effect. This is a change to the behaviour documented for -5.10.0. - -=item C<mro> - -Upgraded from version 1.00 to 1.01. Performance for single inheritance is 40% -faster - see L</"Performance Enhancements"> below. - -C<mro> is now implemented as an XS extension. The documented interface has not -changed. Code relying on the implementation detail that some C<mro::> -methods happened to be available at all times gets to "keep both pieces". - -=back - -=head2 Updated Modules - -=over 4 - -=item C<ExtUtils::MakeMaker> - -Upgraded from version 6.42 to 6.55_02. - -Note that C<ExtUtils::MakeMaker::bytes> and C<ExtUtils::MakeMaker::vmsish> -have been removed from this distribution. - -=item C<Test::Harness> - -Upgraded from version 2.64 to 3.17. - -Note that one side-effect of the 2.x to 3.x upgrade is that the -experimental C<Test::Harness::Straps> module (and its supporting -C<Assert>, C<Iterator>, C<Point> and C<Results> modules) have been -removed. If you still need this, then they are available in the -(unmaintained) C<Test-Harness-Straps> distribution on CPAN. - -=item C<UNIVERSAL> - -Upgraded from version 1.04 to 1.05. - -C<< UNIVERSAL-E<gt>import() >> is now deprecated. - -=back - -=head1 Utility Changes - -=over 4 - -=item F<h2ph> - -Now looks in C<include-fixed> too, which is a recent addition to gcc's -search path. - -=item F<h2xs> - -No longer incorrectly treats enum values like macros (Daniel Burr). - -Now handles C++ style constants (C<//>) properly in enums. (A patch from -Rainer Weikusat was used; Daniel Burr also proposed a similar fix). - -=item F<perl5db.pl> - -C<LVALUE> subroutines now work under the debugger. - -The debugger now correctly handles proxy constant subroutines, and -subroutine stubs. - -=item F<perlbug> - -F<perlbug> now uses C<%Module::CoreList::bug_tracker> to print out upstream bug -tracker URLs. - -Where the user names a module that their bug report is about, and we know the -URL for its upstream bug tracker, provide a message to the user explaining -that the core copies the CPAN version directly, and provide the URL for -reporting the bug directly to upstream. - -=item F<perlthanks> - -Perl 5.11.0 added a new utility F<perlthanks>, which is a variant of -F<perlbug>, but for sending non-bug-reports to the authors and maintainers -of Perl. Getting nothing but bug reports can become a bit demoralising: -we'll see if this changes things. - -=back - -=head1 New Documentation - -=over 4 - -=item L<perlhaiku> - -This contains instructions on how to build perl for the Haiku platform. - -=item L<perlmroapi> - -This describes the new interface for pluggable Method Resolution Orders. - -=item L<perlperf> - -This document, by Richard Foley, provides an introduction to the use of -performance and optimization techniques which can be used with particular -reference to perl programs. - -=item L<perlrepository> - -This describes how to access the perl source using the I<git> version -control system. - -=back - -=head1 Changes to Existing Documentation - -The various large F<Changes*> files (which listed every change made to perl -over the last 18 years) have been removed, and replaced by a small file, -also called F<Changes>, which just explains how that same information may -be extracted from the git version control system. - -The file F<Porting/patching.pod> has been deleted, as it mainly described -interacting with the old Perforce-based repository, which is now obsolete. -Information still relevant has been moved to L<perlrepository>. - -L<perlapi>, L<perlintern>, L<perlmodlib> and L<perltoc> are now all -generated at build time, rather than being shipped as part of the release. - -=over - -=item * - -Documented -X overloading. - -=item * - -Documented that C<when()> treats specially most of the filetest operators - -=item * - -Documented when as a syntax modifier - -=item * - -Eliminated "Old Perl threads tutorial", which describes 5005 threads. - -F<pod/perlthrtut.pod> is the same material reworked for ithreads. - -=item * - -Correct previous documentation: v-strings are not deprecated - -With version objects, we need them to use MODULE VERSION syntax. This -patch removes the deprecation note. - -=item * - -Added security contact information to L<perlsec> - -=back - -=head1 Performance Enhancements - - -=over 4 - -=item * - -A new internal cache means that C<isa()> will often be faster. - -=item * - -The implementation of C<C3> Method Resolution Order has been optimised - -linearisation for classes with single inheritance is 40% faster. Performance -for multiple inheritance is unchanged. - -=item * - -Under C<use locale>, the locale-relevant information is now cached on -read-only values, such as the list returned by C<keys %hash>. This makes -operations such as C<sort keys %hash> in the scope of C<use locale> much -faster. - -=item * - -Empty C<DESTROY> methods are no longer called. - -=item * - -Faster C<Perl_sv_utf8_upgrade()> - -=item * - -Speed up C<keys> on empty hash - -=back - -=head1 Installation and Configuration Improvements - -=head2 F<ext/> reorganisation - -The layout of directories in F<ext> has been revised. Specifically, all -extensions are now flat, and at the top level, with C</> in pathnames -replaced by C<->, so that F<ext/Data/Dumper/> is now F<ext/Data-Dumper/>, -etc. The names of the extensions as specified to F<Configure>, and as -reported by C<%Config::Config> under the keys C<dynamic_ext>, -C<known_extensions>, C<nonxs_ext> and C<static_ext> have not changed, and -still use C</>. Hence this change will not have any affect once perl is -installed. C<Safe> has been split out from being part of C<Opcode>, and -C<mro> is now an extension in its own right. - -Nearly all dual-life modules have been moved from F<lib> to F<ext>, and will -now appear as known C<nonxs_ext>. This will made no difference to the -structure of an installed perl, nor will the modules installed differ, -unless you run F<Configure> with options to specify an exact list of -extensions to build. In this case, you will rapidly become aware that you -need to add to your list, because various modules needed to complete the -build, such as C<ExtUtils::ParseXS>, have now become extensions, and -without them the build will fail well before it attempts to run the -regression tests. - -=head2 Configuration improvements - -If C<vendorlib> and C<vendorarch> are the same, then they are only added to -C<@INC> once. - -C<$Config{usedevel}> and the C-level C<PERL_USE_DEVEL> are now defined if -perl is built with C<-Dusedevel>. - -F<Configure> will enable use of C<-fstack-protector>, to provide protection -against stack-smashing attacks, if the compiler supports it. - -F<Configure> will now determine the correct prototypes for re-entrant -functions, and for C<gconvert>, if you are using a C++ compiler rather -than a C compiler. - -On Unix, if you build from a tree containing a git repository, the -configuration process will note the commit hash you have checked out, for -display in the output of C<perl -v> and C<perl -V>. Unpushed local commits -are automatically added to the list of local patches displayed by -C<perl -V>. - -=head2 Compilation improvements - -As part of the flattening of F<ext>, all extensions on all platforms are -built by F<make_ext.pl>. This replaces the Unix-specific -F<ext/util/make_ext>, VMS-specific F<make_ext.com> and Win32-specific -F<win32/buildext.pl>. - -=head2 Platform Specific Changes - -=over 4 - -=item AIX - -Removed F<libbsd> for AIX 5L and 6.1. Only C<flock()> was used from F<libbsd>. - -Removed F<libgdbm> for AIX 5L and 6.1. The F<libgdbm> is delivered as an -optional package with the AIX Toolbox. Unfortunately the 64 bit version -is broken. - -Hints changes mean that AIX 4.2 should work again. - -=item Cygwin - -On Cygwin we now strip the last number from the DLL. This has been the -behaviour in the cygwin.com build for years. The hints files have been -updated. - -=item DomainOS - -Support for Apollo DomainOS was removed in Perl 5.11.0 - -=item FreeBSD - -The hints files now identify the correct threading libraries on FreeBSD 7 -and later. - -=item Irix - -We now work around a bizarre preprocessor bug in the Irix 6.5 compiler: -C<cc -E -> unfortunately goes into K&R mode, but C<cc -E file.c> doesn't. - -=item Haiku - -Patches from the Haiku maintainers have been merged in. Perl should now -build on Haiku. - -=item MachTen - -Support for Tenon Intersystems MachTen Unix layer for MacOS Classic was -removed in Perl 5.11.0 - -=item MiNT - -Support for Atari MiNT was removed in Perl 5.11.0. - -=item MirOS BSD - -Perl should now build on MirOS BSD. - -=item NetBSD - -Hints now supports versions 5.*. - -=item Stratus VOS - -Various changes from Stratus have been merged in. - -=item Symbian - -There is now support for Symbian S60 3.2 SDK and S60 5.0 SDK. - -=item Win32 - -Improved message window handling means that C<alarm> and C<kill> messages -will no longer be dropped under race conditions. - -=item VMS - -Reads from the in-memory temporary files of C<PerlIO::scalar> used to fail -if C<$/> was set to a numeric reference (to indicate record-style reads). -This is now fixed. - -VMS now supports C<getgrgid>. - -Many improvements and cleanups have been made to the VMS file name handling -and conversion code. - -Enabling the C<PERL_VMS_POSIX_EXIT> logical name now encodes a POSIX exit -status in a VMS condition value for better interaction with GNV's bash -shell and other utilities that depend on POSIX exit values. See -L<perlvms/"$?"> for details. - -C<File::Copy> now detects Unix compatibility mode on VMS. - -=back - -=head1 Selected Bug Fixes - -=over 4 - -=item * - -C<-I> on shebang line now adds directories in front of @INC -as documented, and as does C<-I> when specified on the command-line. - -=item * - -C<kill> is now fatal when called on non-numeric process identifiers. -Previously, an 'undef' process identifier would be interpreted as a request to -kill process "0", which would terminate the current process group on POSIX -systems. Since process identifiers are always integers, killing a non-numeric -process is now fatal. - -=item * - -5.10.0 inadvertently disabled an optimisation, which caused a measurable -performance drop in list assignment, such as is often used to assign -function parameters from C<@_>. The optimisation has been re-instated, and -the performance regression fixed. - -=item * - -Fixed memory leak on C<while (1) { map 1, 1 }> [RT #53038]. - -=item * - -Some potential coredumps in PerlIO fixed [RT #57322,54828]. - -=item * - -The debugger now works with lvalue subroutines. - -=item * - -The debugger's C<m> command was broken on modules that defined constants -[RT #61222]. - -=item * - -C<crypt> and string complement could return tainted values for untainted -arguments [RT #59998]. - -=item * - -The C<-i>I<.suffix> command-line switch now recreates the file using -restricted permissions, before changing its mode to match the original -file. This eliminates a potential race condition [RT #60904]. - -=item * - -On some Unix systems, the value in C<$?> would not have the top bit set -(C<$? & 128>) even if the child core dumped. - -=item * - -Under some circumstances, C<$^R> could incorrectly become undefined -[RT #57042]. - -=item * - -In the XS API, various hash functions, when passed a pre-computed hash where -the key is UTF-8, might result in an incorrect lookup. - -=item * - -XS code including F<XSUB.h> before F<perl.h> gave a compile-time error -[RT #57176]. - -=item * - -C<< $object-E<gt>isa('Foo') >> would report false if the package C<Foo> didn't -exist, even if the object's C<@ISA> contained C<Foo>. - -=item * - -Various bugs in the new-to 5.10.0 mro code, triggered by manipulating -C<@ISA>, have been found and fixed. - -=item * - -Bitwise operations on references could crash the interpreter, e.g. -C<$x=\$y; $x |= "foo"> [RT #54956]. - -=item * - -Patterns including alternation might be sensitive to the internal UTF-8 -representation, e.g. - - my $byte = chr(192); - my $utf8 = chr(192); utf8::upgrade($utf8); - $utf8 =~ /$byte|X}/i; # failed in 5.10.0 - -=item * - -Within UTF8-encoded Perl source files (i.e. where C<use utf8> is in -effect), double-quoted literal strings could be corrupted where a C<\xNN>, -C<\0NNN> or C<\N{}> is followed by a literal character with ordinal value -greater than 255 [RT #59908]. - -=item * - -C<B::Deparse> failed to correctly deparse various constructs: -C<readpipe STRING> [RT #62428], C<CORE::require(STRING)> [RT #62488], -C<sub foo(_)> [RT #62484]. - -=item * - -Using C<setpgrp> with no arguments could corrupt the perl stack. - -=item * - -The block form of C<eval> is now specifically trappable by C<Safe> and -C<ops>. Previously it was erroneously treated like string C<eval>. - -=item * - -In 5.10.0, the two characters C<[~> were sometimes parsed as the smart -match operator (C<~~>) [RT #63854]. - -=item * - -In 5.10.0, the C<*> quantifier in patterns was sometimes treated as -C<{0,32767}> [RT #60034, #60464]. For example, this match would fail: - - ("ab" x 32768) =~ /^(ab)*$/ - -=item * - -C<shmget> was limited to a 32 bit segment size on a 64 bit OS [RT #63924]. - -=item * - -Using C<next> or C<last> to exit a C<given> block no longer produces a -spurious warning like the following: - - Exiting given via last at foo.pl line 123 - -=item * - -On Windows, C<'.\foo'> and C<'..\foo'> were treated differently than -C<'./foo'> and C<'../foo'> by C<do> and C<require> [RT #63492]. - -=item * - -Assigning a format to a glob could corrupt the format; e.g.: - - *bar=*foo{FORMAT}; # foo format now bad - -=item * - -Attempting to coerce a typeglob to a string or number could cause an -assertion failure. The correct error message is now generated, -C<Can't coerce GLOB to I<$type>>. - -=item * - -Under C<use filetest 'access'>, C<-x> was using the wrong access mode. This -has been fixed [RT #49003]. - -=item * - -C<length> on a tied scalar that returned a Unicode value would not be -correct the first time. This has been fixed. - -=item * - -Using an array C<tie> inside in array C<tie> could SEGV. This has been -fixed. [RT #51636] - -=item * - -A race condition inside C<PerlIOStdio_close()> has been identified and -fixed. This used to cause various threading issues, including SEGVs. - -=item * - -In C<unpack>, the use of C<()> groups in scalar context was internally -placing a list on the interpreter's stack, which manifested in various -ways, including SEGVs. This is now fixed [RT #50256]. - -=item * - -Magic was called twice in C<substr>, C<\&$x>, C<tie $x, $m> and C<chop>. -These have all been fixed. - -=item * - -A 5.10.0 optimisation to clear the temporary stack within the implicit -loop of C<s///ge> has been reverted, as it turned out to be the cause of -obscure bugs in seemingly unrelated parts of the interpreter [commit -ef0d4e17921ee3de]. - -=item * - -The line numbers for warnings inside C<elsif> are now correct. - -=item * - -The C<..> operator now works correctly with ranges whose ends are at or -close to the values of the smallest and largest integers. - -=item * - -C<binmode STDIN, ':raw'> could lead to segmentation faults on some platforms. -This has been fixed [RT #54828]. - -=item * - -An off-by-one error meant that C<index $str, ...> was effectively being -executed as C<index "$str\0", ...>. This has been fixed [RT #53746]. - -=item * - -Various leaks associated with named captures in regexes have been fixed -[RT #57024]. - -=item * - -A weak reference to a hash would leak. This was affecting C<DBI> -[RT #56908]. - -=item * - -Using (?|) in a regex could cause a segfault [RT #59734]. - -=item * - -Use of a UTF-8 C<tr//> within a closure could cause a segfault [RT #61520]. - -=item * - -Calling C<Perl_sv_chop()> or otherwise upgrading an SV could result in an -unaligned 64-bit access on the SPARC architecture [RT #60574]. - -=item * - -In the 5.10.0 release, C<inc_version_list> would incorrectly list -C<5.10.*> after C<5.8.*>; this affected the C<@INC> search order -[RT #67628]. - -=item * - -In 5.10.0, C<pack "a*", $tainted_value> returned a non-tainted value -[RT #52552]. - -=item * - -In 5.10.0, C<printf> and C<sprintf> could produce the fatal error -C<panic: utf8_mg_pos_cache_update> when printing UTF-8 strings -[RT #62666]. - -=item * - -In the 5.10.0 release, a dynamically created C<AUTOLOAD> method might be -missed (method cache issue) [RT #60220,60232]. - -=item * - -In the 5.10.0 release, a combination of C<use feature> and C<//ee> could -cause a memory leak [RT #63110]. - -=item * - -C<-C> on the shebang (C<#!>) line is once more permitted if it is also -specified on the command line. C<-C> on the shebang line used to be a -silent no-op I<if> it was not also on the command line, so perl 5.10.0 -disallowed it, which broke some scripts. Now perl checks whether it is -also on the command line and only dies if it is not [RT #67880]. - -=item * - -In 5.10.0, certain types of re-entrant regular expression could crash, -or cause the following assertion failure [RT #60508]: - - Assertion rx->sublen >= (s - rx->subbeg) + i failed - -=item * - -Previously missing files from Unicode 5.1 Character Database are now included. - -=item * - -C<TMPDIR> is now honored when opening an anonymous temporary file - -=back - -=head1 New or Changed Diagnostics - -=over 4 - -=item C<panic: sv_chop %s> - -This new fatal error occurs when the C routine C<Perl_sv_chop()> was -passed a position that is not within the scalar's string buffer. This -could be caused by buggy XS code, and at this point recovery is not -possible. - -=item C<Can't locate package %s for the parents of %s> - -This warning has been removed. In general, it only got produced in -conjunction with other warnings, and removing it allowed an ISA lookup -optimisation to be added. - -=item C<v-string in use/require is non-portable> - -This warning has been removed. - -=item C<Deep recursion on subroutine "%s"> - -It is now possible to change the depth threshold for this warning from the -default of 100, by recompiling the F<perl> binary, setting the C -pre-processor macro C<PERL_SUB_DEPTH_WARN> to the desired value. - -=back - -=head1 Changed Internals - -=over 4 - -=item * - -TODO: C<SVt_RV> is gone. RVs are now stored in IVs - -=item * - -TODO: REGEXPs are first class - -=item * - -TODO: OOK is reworked, such that an OOKed scalar is PV not PVIV - -=item * - -The J.R.R. Tolkien quotes at the head of C source file have been checked and -proper citations added, thanks to a patch from Tom Christiansen. - -=item * - -C<Perl_vcroak()> now accepts a null first argument. In addition, a full audit -was made of the "not NULL" compiler annotations, and those for several -other internal functions were corrected. - -=item * - -New macros C<dSAVEDERRNO>, C<dSAVE_ERRNO>, C<SAVE_ERRNO>, C<RESTORE_ERRNO> -have been added to formalise the temporary saving of the C<errno> -variable. - -=item * - -The function C<Perl_sv_insert_flags> has been added to augment -C<Perl_sv_insert>. - -=item * - -The function C<Perl_newSV_type(type)> has been added, equivalent to -C<Perl_newSV()> followed by C<Perl_sv_upgrade(type)>. - -=item * - -The function C<Perl_newSVpvn_flags()> has been added, equivalent to -C<Perl_newSVpvn()> and then performing the action relevant to the flag. - -Two flag bits are currently supported. - -=over 4 - -=item C<SVf_UTF8> - -This will call C<SvUTF8_on()> for you. (Note that this does not convert an -sequence of ISO 8859-1 characters to UTF-8). A wrapper, C<newSVpvn_utf8()> -is available for this. - -=item C<SVs_TEMP> - -Call C<Perl_sv_2mortal()> on the new SV. - -=back - -There is also a wrapper that takes constant strings, C<newSVpvs_flags()>. - -=item * - -The function C<Perl_croak_xs_usage> has been added as a wrapper to -C<Perl_croak>. - -=item * - -The functions C<PerlIO_find_layer> and C<PerlIO_list_alloc> are now -exported. - -=item * - -C<PL_na> has been exterminated from the core code, replaced by local STRLEN -temporaries, or C<*_nolen()> calls. Either approach is faster than C<PL_na>, -which is a pointer deference into the interpreter structure under ithreads, -and a global variable otherwise. - -=item * - -C<Perl_mg_free()> used to leave freed memory accessible via C<SvMAGIC()> on -the scalar. It now updates the linked list to remove each piece of magic -as it is freed. - -=item * - -Under ithreads, the regex in C<PL_reg_curpm> is now reference counted. This -eliminates a lot of hackish workarounds to cope with it not being reference -counted. - -=item * - -C<Perl_mg_magical()> would sometimes incorrectly turn on C<SvRMAGICAL()>. -This has been fixed. - -=item * - -The I<public> IV and NV flags are now not set if the string value has -trailing "garbage". This behaviour is consistent with not setting the -public IV or NV flags if the value is out of range for the type. - -=item * - -SV allocation tracing has been added to the diagnostics enabled by C<-Dm>. -The tracing can alternatively output via the C<PERL_MEM_LOG> mechanism, if -that was enabled when the F<perl> binary was compiled. - -=item * - -Smartmatch resolution tracing has been added as a new diagnostic. Use C<-DM> to -enable it. - - -=item * - -A new debugging flag C<-DB> now dumps subroutine definitions, leaving -C<-Dx> for its original purpose of dumping syntax trees. - -=item * - -Uses of C<Nullav>, C<Nullcv>, C<Nullhv>, C<Nullop>, C<Nullsv> etc have been -replaced by C<NULL> in the core code, and non-dual-life modules, as C<NULL> -is clearer to those unfamiliar with the core code. - -=item * - -A macro C<MUTABLE_PTR(p)> has been added, which on (non-pedantic) gcc will -not cast away C<const>, returning a C<void *>. Macros C<MUTABLE_SV(av)>, -C<MUTABLE_SV(cv)> etc build on this, casting to C<AV *> etc without -casting away C<const>. This allows proper compile-time auditing of -C<const> correctness in the core, and helped picked up some errors (now -fixed). - -=item * - -Macros C<mPUSHs()> and C<mXPUSHs()> have been added, for pushing SVs on the -stack and mortalizing them. - -=item * - -Use of the private structure C<mro_meta> has changed slightly. Nothing -outside the core should be accessing this directly anyway. - -=item * - -A new tool, F<Porting/expand-macro.pl> has been added, that allows you -to view how a C preprocessor macro would be expanded when compiled. -This is handy when trying to decode the macro hell that is the perl -guts. - -=back - -=head1 New Tests - -Many modules updated from CPAN incorporate new tests. - -Several tests that have the potential to hang forever if they fail now -incorporate a "watchdog" functionality that will kill them after a timeout, -which helps ensure that C<make test> and C<make test_harness> run to -completion automatically. (Jerry Hedden). - -Some core-specific tests have been added: - -=over 4 - -=item t/comp/retainedlines.t - -Check that the debugger can retain source lines from C<eval>. - -=item t/io/perlio_fail.t - -Check that bad layers fail. - -=item t/io/perlio_leaks.t - -Check that PerlIO layers are not leaking. - -=item t/io/perlio_open.t - -Check that certain special forms of open work. - -=item t/io/perlio.t - -General PerlIO tests. - -=item t/io/pvbm.t - -Check that there is no unexpected interaction between the internal types -C<PVBM> and C<PVGV>. - -=item t/mro/package_aliases.t - -Check that mro works properly in the presence of aliased packages. - -=item t/op/dbm.t - -Tests for C<dbmopen> and C<dbmclose>. - -=item t/op/index_thr.t - -Tests for the interaction of C<index> and threads. - -=item t/op/pat_thr.t - -Tests for the interaction of esoteric patterns and threads. - -=item t/op/qr_gc.t - -Test that C<qr> doesn't leak. - -=item t/op/reg_email_thr.t - -Tests for the interaction of regex recursion and threads. - -=item t/op/regexp_qr_embed_thr.t - -Tests for the interaction of patterns with embedded C<qr//> and threads. - -=item t/op/regexp_unicode_prop.t - -Tests for Unicode properties in regular expressions. - -=item t/op/regexp_unicode_prop_thr.t - -Tests for the interaction of Unicode properties and threads. - -=item t/op/reg_nc_tie.t - -Test the tied methods of C<Tie::Hash::NamedCapture>. - -=item t/op/reg_posixcc.t - -Check that POSIX character classes behave consistently. - -=item t/op/re.t - -Check that exportable C<re> functions in F<universal.c> work. - -=item t/op/setpgrpstack.t - -Check that C<setpgrp> works. - -=item t/op/substr_thr.t - -Tests for the interaction of C<substr> and threads. - -=item t/op/upgrade.t - -Check that upgrading and assigning scalars works. - -=item t/uni/lex_utf8.t - -Check that Unicode in the lexer works. - -=item t/uni/tie.t - -Check that Unicode and C<tie> work. - -=back - -=head1 Known Problems - -This is a list of some significant unfixed bugs, which are regressions -from either 5.10.0 or 5.8.x. - -=over 4 - -=item * - -C<List::Util::first> misbehaves in the presence of a lexical C<$_> -(typically introduced by C<my $_> or implicitly by C<given>). The variable -which gets set for each iteration is the package variable C<$_>, not the -lexical C<$_> [RT #67694]. - -A similar issue may occur in other modules that provide functions which -take a block as their first argument, like - - foo { ... $_ ...} list - -=item * - -The C<charnames> pragma may generate a run-time error when a regex is -interpolated [RT #56444]: - - use charnames ':full'; - my $r1 = qr/\N{THAI CHARACTER SARA I}/; - "foo" =~ $r1; # okay - "foo" =~ /$r1+/; # runtime error - -A workaround is to generate the character outside of the regex: - - my $a = "\N{THAI CHARACTER SARA I}"; - my $r1 = qr/$a/; - -=item * - -Some regexes may run much more slowly when run in a child thread compared -with the thread the pattern was compiled into [RT #55600]. - -=back - -=head1 Deprecations - -The following items are now deprecated. - -=over 4 - -=item * - -C<Switch> is buggy and should be avoided. From perl 5.11.0 onwards, it is -intended that any use of the core version of this module will emit a -warning, and that the module will eventually be removed from the core -(probably in perl 5.14.0). See L<perlsyn/"Switch statements"> for its -replacement. - -=item * - -The following modules will be removed from the core distribution in a future -release, and should be installed from CPAN instead. Distributions on CPAN -which require these should add them to their prerequisites. The core versions -of these modules warnings will issue a deprecation warning. - -=over - -=item * - -C<Class::ISA> - -=item * - -C<Pod::Plainer> - -=item * - -C<Shell> - -=back - -Currently support to install from CPAN without a I<force> is C<TODO> in CPAN -and CPANPLUS. This will be addressed before 5.12.0 ships. - -=item * - -C<suidperl> has been removed. It used to provide a mechanism to -emulate setuid permission bits on systems that don't support it properly. - -=item * - -Deprecate assignment to $[ - -=item * - -Remove attrs, which has been deprecated since 1999/10/02. - -=item * - -Deprecate use of the attribute :locked on subroutines. - -=item * - -Deprecate using "locked" with the attributes pragma. - -=item * - -Deprecate using "unique" with the attributes pragma. - -=item * - -warn if ++ or -- are unable to change the value because it's beyond the limit of representation - -This uses a new warnings category: "imprecision". - -=item * - -Make lc/uc/lcfirst/ucfirst warn when passed undef. - -=item * - -Show constant in "Useless use of a constant in void context" - -=item * - -Make the new warning report undef constants as undef - -=item * - -Add a new warning, "Prototype after '%s'" - -=item * - -Tweak the "Illegal character in prototype" warning so it's more precise when reporting illegal characters after _ - -=item * - -Unintended interpolation of $\ in regex - -=item * - -Make overflow warnings in gmtime/localtime only occur when warnings are on - -=item * - -Improve mro merging error messages. - -They are now very similar to those produced by Algorithm::C3. - -=item * - -Amelioration of the error message "Unrecognized character %s in column %d" - -Changes the error message to "Unrecognized character %s; marked by E<lt>-- -HERE after %sE<lt>-- HERE near column %d". This should make it a little -simpler to spot and correct the suspicious character. - -=item * - -Explicitly point to $. when it causes an uninitialized warning for ranges in scalar context - - -=item * - -Deprecated numerous Perl 4-era libraries: - -F<termcap.pl>, F<tainted.pl>, F<stat.pl>, F<shellwords.pl>, F<pwd.pl>, -F<open3.pl>, F<open2.pl>, F<newgetopt.pl>, F<look.pl>, F<find.pl>, -F<finddepth.pl>, F<importenv.pl>, F<hostname.pl>, F<getopts.pl>, -F<getopt.pl>, F<getcwd.pl>, F<flush.pl>, F<fastcwd.pl>, F<exceptions.pl>, -F<ctime.pl>, F<complete.pl>, F<cacheout.pl>, F<bigrat.pl>, F<bigint.pl>, -F<bigfloat.pl>, F<assert.pl>, F<abbrev.pl>, F<dotsh.pl>, and -F<timelocal.pl> are all now deprecated. Using them will incur a warning. - -=back - -=head1 Acknowledgements - -Some of the work in this release was funded by a TPF grant funded by -Dijkmat BV, The Netherlands. - -Steffen Mueller and David Golden in particular helped getting CPAN modules -polished and synchronised with their in-core equivalents. - -Craig Berry was tireless in getting maint to run under VMS, no matter how -many times we broke it for him. - -The other core committers contributed most of the changes, and applied most -of the patches sent in by the hundreds of contributors listed in F<AUTHORS>. - -Much of the work of categorizing changes in this perldelta file was contributed -by the following porters using changelogger.bestpractical.com: - -Nicholas Clark, leon, shawn, alexm, rjbs, rafl, Pedro Melo, brunorc, -anonymous, ☄, Tom Hukins, anonymous, Jesse, dagolden, Moritz Onken, -Mark Fowler, chorny, anonymous, tmtm - -Finally, thanks to Larry Wall, without whom none of this would be -necessary. - -=head1 Reporting Bugs - -If you find what you think is a bug, you might check the articles -recently posted to the comp.lang.perl.misc newsgroup and the perl -bug database at http://rt.perl.org/perlbug/ . There may also be -information at http://www.perl.org/ , the Perl Home Page. - -If you believe you have an unreported bug, please run the B<perlbug> -program included with your release. Be sure to trim your bug down -to a tiny but sufficient test case. Your bug report, along with the -output of C<perl -V>, will be sent off to perlbug@perl.org to be -analysed by the Perl porting team. - -If the bug you are reporting has security implications, which make it -inappropriate to send to a publicly archived mailing list, then please send -it to perl5-security-report@perl.org. This points to a closed subscription -unarchived mailing list, which includes all the core committers, who be able -to help assess the impact of issues, figure out a resolution, and help -co-ordinate the release of patches to mitigate or fix the problem across all -platforms on which Perl is supported. Please only use this address for -security issues in the Perl core, not for modules independently -distributed on CPAN. - -=head1 SEE ALSO - -The F<Changes> file for an explanation of how to view exhaustive details -on what changed. - -The F<INSTALL> file for how to build Perl. - -The F<README> file for general stuff. - -The F<Artistic> and F<Copying> files for copyright information. - -=cut - - |