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diff --git a/Master/tlpkg/tlperl/lib/pods/perl5120delta.pod b/Master/tlpkg/tlperl/lib/pods/perl5120delta.pod deleted file mode 100644 index f8a1810c861..00000000000 --- a/Master/tlpkg/tlperl/lib/pods/perl5120delta.pod +++ /dev/null @@ -1,3195 +0,0 @@ -=encoding utf8 - -=head1 NAME - -perl5120delta - what is new for perl v5.12.0 - -=head1 DESCRIPTION - -This document describes differences between the 5.10.0 release and the -5.12.0 release. - -Many of the bug fixes in 5.12.0 are already included in the 5.10.1 -maintenance release. - -You can see the list of those changes in the 5.10.1 release notes -(L<perl5101delta>). - - -=head1 Core Enhancements - -=head2 New C<package NAME VERSION> syntax - -This new syntax allows a module author to set the $VERSION of a namespace -when the namespace is declared with 'package'. It eliminates the need -for C<our $VERSION = ...> and similar constructs. E.g. - - package Foo::Bar 1.23; - # $Foo::Bar::VERSION == 1.23 - -There are several advantages to this: - -=over - -=item * - -C<$VERSION> is parsed in exactly the same way as C<use NAME VERSION> - -=item * - -C<$VERSION> is set at compile time - -=item * - -C<$VERSION> is a version object that provides proper overloading of -comparison operators so comparing C<$VERSION> to decimal (1.23) or -dotted-decimal (v1.2.3) version numbers works correctly. - -=item * - -Eliminates C<$VERSION = ...> and C<eval $VERSION> clutter - -=item * - -As it requires VERSION to be a numeric literal or v-string -literal, it can be statically parsed by toolchain modules -without C<eval> the way MM-E<gt>parse_version does for C<$VERSION = ...> - -=back - -It does not break old code with only C<package NAME>, but code that uses -C<package NAME VERSION> will need to be restricted to perl 5.12.0 or newer -This is analogous to the change to C<open> from two-args to three-args. -Users requiring the latest Perl will benefit, and perhaps after several -years, it will become a standard practice. - - -However, C<package NAME VERSION> requires a new, 'strict' version -number format. See L<"Version number formats"> for details. - - -=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">. - -=head2 Implicit strictures - -Using the C<use VERSION> syntax with a version number greater or equal -to 5.11.0 will lexically enable strictures just like C<use strict> -would do (in addition to enabling features.) The following: - - use 5.12.0; - -means: - - use strict; - use feature ':5.12'; - -=head2 Unicode improvements - -Perl 5.12 comes with Unicode 5.2, the latest version available to -us at the time of release. This version of Unicode was released in -October 2009. See L<http://www.unicode.org/versions/Unicode5.2.0> for -further details about what's changed in this version of the standard. -See L<perlunicode> for instructions on installing and using other versions -of Unicode. - -Additionally, Perl's developers have significantly improved Perl's Unicode -implementation. For full details, see L</Unicode overhaul> below. - -=head2 Y2038 compliance - -Perl's core time-related functions are now Y2038 compliant. (It may not mean much to you, but your kids will love it!) - -=head2 qr overloading - -It is now possible to overload the C<qr//> operator, that is, -conversion to regexp, like it was already possible to overload -conversion to boolean, string or number of objects. It is invoked when -an object appears on the right hand side of the C<=~> operator or when -it is interpolated into a regexp. See L<overload>. - -=head2 Pluggable keywords - -Extension modules can now cleanly hook into the Perl parser to define -new kinds of keyword-headed expression and compound statement. The -syntax following the keyword is defined entirely by the extension. This -allow a completely non-Perl sublanguage to be parsed inline, with the -correct ops cleanly generated. - -See L<perlapi/PL_keyword_plugin> for the mechanism. The Perl core -source distribution also includes a new module -L<XS::APItest::KeywordRPN>, which implements reverse Polish notation -arithmetic via pluggable keywords. This module is mainly used for test -purposes, and is not normally installed, but also serves as an example -of how to use the new mechanism. - -Perl's developers consider this feature to be experimental. We may remove -it or change it in a backwards-incompatible way in Perl 5.14. - -=head2 APIs for more internals - -The lowest layers of the lexer and parts of the pad system now have C -APIs available to XS extensions. These are necessary to support proper -use of pluggable keywords, but have other uses too. The new APIs are -experimental, and only cover a small proportion of what would be -necessary to take full advantage of the core's facilities in these -areas. It is intended that the Perl 5.13 development cycle will see the -addition of a full range of clean, supported interfaces. - -Perl's developers consider this feature to be experimental. We may remove -it or change it in a backwards-incompatible way in Perl 5.14. - -=head2 Overridable function lookup - -Where an extension module hooks the creation of rv2cv ops to modify the -subroutine lookup process, this now works correctly for bareword -subroutine calls. This means that prototypes on subroutines referenced -this way will be processed correctly. (Previously bareword subroutine -names were initially looked up, for parsing purposes, by an unhookable -mechanism, so extensions could only properly influence subroutine names -that appeared with an C<&> sigil.) - -=head2 A proper interface for pluggable Method Resolution Orders - -As of Perl 5.12.0 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 C<\N> experimental regex escape - -Perl now supports C<\N>, a new regex escape which you can think of as -the inverse of 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>. It is not usable within a character class. C<\N{3}> -means to match 3 non-newlines; C<\N{5,}> means to match at least 5. -C<\N{NAME}> still means the character or sequence named C<NAME>, but -C<NAME> no longer can be things like C<3>, or C<5,>. - -This will break a L<custom charnames translator|charnames/CUSTOM -TRANSLATORS> which allows numbers for character names, as C<\N{3}> will -now mean to match 3 non-newline characters, and not the character whose -name is C<3>. (No name defined by the Unicode standard is a number, -so only custom translators might be affected.) - -Perl's developers are somewhat concerned about possible user confusion -with the existing C<\N{...}> construct which matches characters by their -Unicode name. Consequently, this feature is experimental. We may remove -it or change it in a backwards-incompatible way in Perl 5.14. - -=head2 DTrace support - -Perl now has some support for DTrace. 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>, C<keys>, C<values> are now more flexible - -The C<each>, C<keys>, C<values> function can now operate on arrays. - -=head2 C<when> as a statement modifier - -C<when> is now allowed to be used as a statement modifier. - -=head2 C<$,> flexibility - -The variable C<$,> may now be tied. - -=head2 // in when 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. - -=head2 32-bit limit on substr arguments removed - -The 32-bit limit on C<substr> arguments has now been removed. The full -range of the system's signed and unsigned integers is now available for -the C<pos> and C<len> arguments. - -=head1 Potentially Incompatible Changes - -=head2 Deprecations warn by default - -Over the years, Perl's developers have deprecated a number of language -features for a variety of reasons. Perl now defaults to issuing a -warning if a deprecated language feature is used. Many of the deprecations -Perl now warns you about have been deprecated for many years. You can -find a list of what was deprecated in a given release of Perl in the -C<perl5xxdelta.pod> file for that release. - -To disable this feature in a given lexical scope, you should use C<no -warnings 'deprecated';> For information about which language features -are deprecated and explanations of various deprecation warnings, please -see L<perldiag>. See L</Deprecations> below for the list of features -and modules Perl's developers have deprecated as part of this release. - -=head2 Version number formats - -Acceptable version number formats have been formalized into "strict" and -"lax" rules. C<package NAME VERSION> takes a strict version number. -C<UNIVERSAL::VERSION> and the L<version> object constructors take lax -version numbers. Providing an invalid version will result in a fatal -error. The version argument in C<use NAME VERSION> is first parsed as a -numeric literal or v-string and then passed to C<UNIVERSAL::VERSION> -(and must then pass the "lax" format test). - -These formats are documented fully in the L<version> module. To a first -approximation, a "strict" version number is a positive decimal number -(integer or decimal-fraction) without exponentiation or else a -dotted-decimal v-string with a leading 'v' character and at least three -components. A "lax" version number allows v-strings with fewer than -three components or without a leading 'v'. Under "lax" rules, both -decimal and dotted-decimal versions may have a trailing "alpha" -component separated by an underscore character after a fractional or -dotted-decimal component. - -The L<version> module adds C<version::is_strict> and C<version::is_lax> -functions to check a scalar against these rules. - -=head2 @INC reorganization - -In C<@INC>, C<ARCHLIB> and C<PRIVLIB> now occur after after the current -version's C<site_perl> and C<vendor_perl>. Modules installed into -C<site_perl> and C<vendor_perl> will now be loaded in preference to -those installed in C<ARCHLIB> and C<PRIVLIB>. - - -=head2 REGEXPs are now first class - -Internally, Perl now treats compiled regular expressions (such as -those created with C<qr//>) as first class entities. Perl modules which -serialize, deserialize or otherwise have deep interaction with Perl's -internal data structures need to be updated for this change. Most -affected CPAN modules have already been updated as of this writing. - -=head2 Switch statement changes - -The C<given>/C<when> switch statement handles complex statements better -than Perl 5.10.0 did (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 - -=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 - -=head2 Smart match changes - -Since Perl 5.10.0, Perl's developers have made a number of changes to -the smart match operator. These, of course, also alter the behaviour -of the switch statements where smart matching is implicitly used. -These changes were also made for the 5.10.1 release, and will remain in -subsequent 5.10 releases. - -=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 Other potentially incompatible changes - -=over 4 - -=item * - -The definitions of a number of Unicode properties have changed to match -those of the current Unicode standard. These are listed above under -L</Unicode overhaul>. This change may break code that expects the old -definitions. - -=item * - -The boolkeys op has moved to the group of hash ops. This breaks binary -compatibility. - -=item * - -Filehandles are now always blessed into C<IO::File>. - -The previous behaviour was to bless Filehandles into L<FileHandle> -(an empty proxy class) if it was loaded into memory and otherwise -to bless them into C<IO::Handle>. - -=item * - -The semantics of C<use feature :5.10*> have changed slightly. -See L<"Modules and Pragmata"> for more information. - -=item * - -Perl's developers now use git, rather than Perforce. This should be -a purely internal change only relevant to people actively working on -the core. However, you may see minor difference in perl as a consequence -of the change. For example in some of details of the output of C<perl --V>. See L<perlrepository> for more information. - -=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</"Modules and Pragmata"> 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 * - -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 C<-I...>, the split of -C<$ENV{PERL5LIB}>, and "C<.>" - -=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. - -=item * - -Perl's command-line switch "-P", which was deprecated in version 5.10.0, has -now been removed. The CPAN module C<< Filter::cpp >> can be used as an -alternative. - -=back - - -=head1 Deprecations - -From time to time, Perl's developers find it necessary to deprecate -features or modules we've previously shipped as part of the core -distribution. We are well aware of the pain and frustration that a -backwards-incompatible change to Perl can cause for developers building -or maintaining software in Perl. You can be sure that when we deprecate -a functionality or syntax, it isn't a choice we make lightly. Sometimes, -we choose to deprecate functionality or syntax because it was found to -be poorly designed or implemented. Sometimes, this is because they're -holding back other features or causing performance problems. Sometimes, -the reasons are more complex. Wherever possible, we try to keep deprecated -functionality available to developers in its previous form for at least -one major release. So long as a deprecated feature isn't actively -disrupting our ability to maintain and extend Perl, we'll try to leave -it in place as long as possible. - -The following items are now deprecated: - -=over - -=item suidperl - -C<suidperl> is no longer part of Perl. It used to provide a mechanism to -emulate setuid permission bits on systems that don't support it properly. - -=item Use of C<:=> to mean an empty attribute list - -An accident of Perl's parser meant that these constructions were all -equivalent: - - my $pi := 4; - my $pi : = 4; - my $pi : = 4; - -with the C<:> being treated as the start of an attribute list, which -ends before the C<=>. As whitespace is not significant here, all are -parsed as an empty attribute list, hence all the above are equivalent -to, and better written as - - my $pi = 4; - -because no attribute processing is done for an empty list. - -As is, this meant that C<:=> cannot be used as a new token, without -silently changing the meaning of existing code. Hence that particular -form is now deprecated, and will become a syntax error. If it is -absolutely necessary to have empty attribute lists (for example, -because of a code generator) then avoid the warning by adding a space -before the C<=>. - -=item C<< UNIVERSAL->import() >> - -The method C<< UNIVERSAL->import() >> is now deprecated. Attempting to -pass import arguments to a C<use UNIVERSAL> statement will result in a -deprecation warning. - -=item Use of "goto" to jump into a construct - -Using C<goto> to jump from an outer scope into an inner scope is now -deprecated. This rare use case was causing problems in the -implementation of scopes. - -=item Custom character names in \N{name} that don't look like names - -In C<\N{I<name>}>, I<name> can be just about anything. The standard -Unicode names have a very limited domain, but a custom name translator -could create names that are, for example, made up entirely of punctuation -symbols. It is now deprecated to make names that don't begin with an -alphabetic character, and aren't alphanumeric or contain other than -a very few other characters, namely spaces, dashes, parentheses -and colons. Because of the added meaning of C<\N> (See L</C<\N> -experimental regex escape>), names that look like curly brace -enclosed -quantifiers won't work. For example, C<\N{3,4}> now means to match 3 to -4 non-newlines; before a custom name C<3,4> could have been created. - -=item Deprecated Modules - -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. - -If you ship a packaged version of Perl, either alone or as part of a -larger system, then you should carefully consider the repercussions of -core module deprecations. You may want to consider shipping your default -build of Perl with packages for some or all deprecated modules which -install into C<vendor> or C<site> perl library directories. This will -inhibit the deprecation warnings. - -Alternatively, you may want to consider patching F<lib/deprecate.pm> -to provide deprecation warnings specific to your packaging system -or distribution of Perl, consistent with how your packaging system -or distribution manages a staged transition from a release where the -installation of a single package provides the given functionality, to -a later release where the system administrator needs to know to install -multiple packages to get that same functionality. - -You can silence these deprecation warnings by installing the modules -in question from CPAN. To install the latest version of all of them, -just install C<Task::Deprecations::5_12>. - -=over - -=item L<Class::ISA> - -=item L<Pod::Plainer> - -=item L<Shell> - -=item L<Switch> - -Switch is buggy and should be avoided. You may find Perl's new -C<given>/C<when> feature a suitable replacement. See L<perlsyn/"Switch -statements"> for more information. - -=back - -=item Assignment to $[ - -=item Use of the attribute :locked on subroutines - -=item Use of "locked" with the attributes pragma - -=item Use of "unique" with the attributes pragma - -=item Perl_pmflag - -C<Perl_pmflag> is no longer part of Perl's public API. Calling it now -generates a deprecation warning, and it will be removed in a future -release. Although listed as part of the API, it was never documented, -and only ever used in F<toke.c>, and prior to 5.10, F<regcomp.c>. In -core, it has been replaced by a static function. - -=item 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. Earlier, Perl's developers -intended to remove these libraries from Perl's core for the 5.14.0 release. - -During final testing before the release of 5.12.0, several developers -discovered current production code using these ancient libraries, some -inside the Perl core itself. Accordingly, the pumpking granted them -a stay of execution. They will begin to warn about their deprecation -in the 5.14.0 release and will be removed in the 5.16.0 release. - - -=back - -=head1 Unicode overhaul - -Perl's developers have made a concerted effort to update Perl to be in -sync with the latest Unicode standard. Changes for this include: - -Perl can now handle every Unicode character property. New documentation, -L<perluniprops>, lists all available non-Unihan character properties. By -default, perl does not expose Unihan, deprecated or Unicode-internal -properties. See below for more details on these; there is also a section -in the pod listing them, and explaining why they are not exposed. - -Perl now fully supports the Unicode compound-style of using C<=> -and C<:> in writing regular expressions: C<\p{property=value}> and -C<\p{property:value}> (both of which mean the same thing). - -Perl now fully supports the Unicode loose matching rules for text between -the braces in C<\p{...}> constructs. In addition, Perl allows underscores -between digits of numbers. - -Perl now accepts all the Unicode-defined synonyms for properties and -property values. - -C<qr/\X/>, which matches a Unicode logical character, has -been expanded to work better with various Asian languages. It -now is defined as an I<extended grapheme cluster>. (See -L<http://www.unicode.org/reports/tr29/>). Anything matched previously -and that made sense will continue to be accepted. Additionally: - -=over - -=item * - -C<\X> will not break apart a C<S<CR LF>> sequence. - -=item * - -C<\X> will now match a sequence which includes the C<ZWJ> and C<ZWNJ> -characters. - -=item * - -C<\X> will now always match at least one character, including an initial -mark. Marks generally come after a base character, but it is possible in -Unicode to have them in isolation, and C<\X> will now handle that case, -for example at the beginning of a line, or after a C<ZWSP>. And this is -the part where C<\X> doesn't match the things that it used to that don't -make sense. Formerly, for example, you could have the nonsensical case -of an accented LF. - -=item * - -C<\X> will now match a (Korean) Hangul syllable sequence, and the Thai -and Lao exception cases. - -=back - -Otherwise, this change should be transparent for the non-affected -languages. - -C<\p{...}> matches using the Canonical_Combining_Class property were -completely broken in previous releases of Perl. They should now work -correctly. - -Before Perl 5.12, the Unicode C<Decomposition_Type=Compat> property -and a Perl extension had the same name, which led to neither matching -all the correct values (with more than 100 mistakes in one, and several -thousand in the other). The Perl extension has now been renamed to be -C<Decomposition_Type=Noncanonical> (short: C<dt=noncanon>). It has the -same meaning as was previously intended, namely the union of all the -non-canonical Decomposition types, with Unicode C<Compat> being just -one of those. - -C<\p{Decomposition_Type=Canonical}> now includes the Hangul syllables. - -C<\p{Uppercase}> and C<\p{Lowercase}> now work as the Unicode standard -says they should. This means they each match a few more characters than -they used to. - -C<\p{Cntrl}> now matches the same characters as C<\p{Control}>. This -means it no longer will match Private Use (gc=co), Surrogates (gc=cs), -nor Format (gc=cf) code points. The Format code points represent the -biggest possible problem. All but 36 of them are either officially -deprecated or strongly discouraged from being used. Of those 36, likely -the most widely used are the soft hyphen (U+00AD), and BOM, ZWSP, ZWNJ, -WJ, and similar characters, plus bidirectional controls. - -C<\p{Alpha}> now matches the same characters as C<\p{Alphabetic}>. Before -5.12, Perl's definition definition included a number of things that aren't -really alpha (all marks) while omitting many that were. The definitions -of C<\p{Alnum}> and C<\p{Word}> depend on Alpha's definition and have -changed accordingly. - -C<\p{Word}> no longer incorrectly matches non-word characters such -as fractions. - -C<\p{Print}> no longer matches the line control characters: Tab, LF, -CR, FF, VT, and NEL. This brings it in line with standards and the -documentation. - -C<\p{XDigit}> now matches the same characters as C<\p{Hex_Digit}>. This -means that in addition to the characters it currently matches, -C<[A-Fa-f0-9]>, it will also match the 22 fullwidth equivalents, for -example U+FF10: FULLWIDTH DIGIT ZERO. - -The Numeric type property has been extended to include the Unihan -characters. - -There is a new Perl extension, the 'Present_In', or simply 'In', -property. This is an extension of the Unicode Age property, but -C<\p{In=5.0}> matches any code point whose usage has been determined -I<as of> Unicode version 5.0. The C<\p{Age=5.0}> only matches code points -added in I<precisely> version 5.0. - -A number of properties now have the correct values for unassigned -code points. The affected properties are Bidi_Class, East_Asian_Width, -Joining_Type, Decomposition_Type, Hangul_Syllable_Type, Numeric_Type, -and Line_Break. - -The Default_Ignorable_Code_Point, ID_Continue, and ID_Start properties -are now up to date with current Unicode definitions. - -Earlier versions of Perl erroneously exposed certain properties that -are supposed to be Unicode internal-only. Use of these in regular -expressions will now generate, if enabled, a deprecation warning message. -The properties are: Other_Alphabetic, Other_Default_Ignorable_Code_Point, -Other_Grapheme_Extend, Other_ID_Continue, Other_ID_Start, Other_Lowercase, -Other_Math, and Other_Uppercase. - -It is now possible to change which Unicode properties Perl understands -on a per-installation basis. As mentioned above, certain properties -are turned off by default. These include all the Unihan properties -(which should be accessible via the CPAN module Unicode::Unihan) and any -deprecated or Unicode internal-only property that Perl has never exposed. - -The generated files in the C<lib/unicore/To> directory are now more -clearly marked as being stable, directly usable by applications. New hash -entries in them give the format of the normal entries, which allows for -easier machine parsing. Perl can generate files in this directory for -any property, though most are suppressed. You can find instructions -for changing which are written in L<perluniprops>. - -=head1 Modules and Pragmata - -=head2 New Modules and Pragmata - -=over 4 - -=item C<autodie> - -C<autodie> 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. - -Version 2.06_01 has been added to the Perl core. - -=item C<Compress::Raw::Bzip2> - -Version 2.024 has been added to the Perl core. - -=item C<overloading> - -C<overloading> allows you to lexically disable or enable overloading -for some or all operations. - -Version 0.001 has been added to the Perl core. - -=item C<parent> - -C<parent> establishes an ISA relationship with base classes at compile -time. It provides the key feature of C<base> without further unwanted -behaviors. - -Version 0.223 has been added to the Perl core. - -=item C<Parse::CPAN::Meta> - -Version 1.40 has been added to the Perl core. - -=item C<VMS::DCLsym> - -Version 1.03 has been added to the Perl core. - -=item C<VMS::Stdio> - -Version 2.4 has been added to the Perl core. - -=item C<XS::APItest::KeywordRPN> - -Version 0.003 has been added to the Perl core. - -=back - -=head2 Updated Pragmata - -=over 4 - -=item C<base> - -Upgraded from version 2.13 to 2.15. - -=item C<bignum> - -Upgraded from version 0.22 to 0.23. - -=item C<charnames> - -C<charnames> now contains the Unicode F<NameAliases.txt> database file. -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}">. - -Upgraded from version 1.06 to 1.07. - -=item C<constant> - -Upgraded from version 1.13 to 1.20. - -=item C<diagnostics> - -C<diagnostics> now supports %.0f formatting internally. - -C<diagnostics> no longer suppresses C<Use of uninitialized value in range -(or flip)> warnings. [perl #71204] - -Upgraded from version 1.17 to 1.19. - -=item C<feature> - -In 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. - -C<feature> now includes the C<unicode_strings> feature: - - use feature "unicode_strings"; - -This pragma turns on Unicode semantics for the case-changing operations -(C<uc>, C<lc>, C<ucfirst>, C<lcfirst>) on strings that don't have the -internal UTF-8 flag set, but that contain single-byte characters between -128 and 255. - -Upgraded from version 1.11 to 1.16. - -=item C<less> - -C<less> now includes the C<stash_name> method to allow subclasses of -C<less> to pick where in %^H to store their stash. - -Upgraded from version 0.02 to 0.03. - -=item C<lib> - -Upgraded from version 0.5565 to 0.62. - -=item C<mro> - -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". - -Upgraded from version 1.00 to 1.02. - -=item C<overload> - -C<overload> now allow overloading of 'qr'. - -Upgraded from version 1.06 to 1.10. - -=item C<threads> - -Upgraded from version 1.67 to 1.75. - -=item C<threads::shared> - -Upgraded from version 1.14 to 1.32. - -=item C<version> - -C<version> now has support for L</Version number formats> as described -earlier in this document and in its own documentation. - -Upgraded from version 0.74 to 0.82. - -=item C<warnings> - -C<warnings> has a new C<warnings::fatal_enabled()> function. It also -includes a new C<illegalproto> warning category. See also L</New or -Changed Diagnostics> for this change. - -Upgraded from version 1.06 to 1.09. - -=back - -=head2 Updated Modules - -=over 4 - -=item C<Archive::Extract> - -Upgraded from version 0.24 to 0.38. - -=item C<Archive::Tar> - -Upgraded from version 1.38 to 1.54. - -=item C<Attribute::Handlers> - -Upgraded from version 0.79 to 0.87. - -=item C<AutoLoader> - -Upgraded from version 5.63 to 5.70. - -=item C<B::Concise> - -Upgraded from version 0.74 to 0.78. - -=item C<B::Debug> - -Upgraded from version 1.05 to 1.12. - -=item C<B::Deparse> - -Upgraded from version 0.83 to 0.96. - -=item C<B::Lint> - -Upgraded from version 1.09 to 1.11_01. - -=item C<CGI> - -Upgraded from version 3.29 to 3.48. - -=item C<Class::ISA> - -Upgraded from version 0.33 to 0.36. - -NOTE: C<Class::ISA> is deprecated and may be removed from a future -version of Perl. - -=item C<Compress::Raw::Zlib> - -Upgraded from version 2.008 to 2.024. - -=item C<CPAN> - -Upgraded from version 1.9205 to 1.94_56. - -=item C<CPANPLUS> - -Upgraded from version 0.84 to 0.90. - -=item C<CPANPLUS::Dist::Build> - -Upgraded from version 0.06_02 to 0.46. - -=item C<Data::Dumper> - -Upgraded from version 2.121_14 to 2.125. - -=item C<DB_File> - -Upgraded from version 1.816_1 to 1.820. - -=item C<Devel::PPPort> - -Upgraded from version 3.13 to 3.19. - -=item C<Digest> - -Upgraded from version 1.15 to 1.16. - -=item C<Digest::MD5> - -Upgraded from version 2.36_01 to 2.39. - -=item C<Digest::SHA> - -Upgraded from version 5.45 to 5.47. - -=item C<Encode> - -Upgraded from version 2.23 to 2.39. - -=item C<Exporter> - -Upgraded from version 5.62 to 5.64_01. - -=item C<ExtUtils::CBuilder> - -Upgraded from version 0.21 to 0.27. - -=item C<ExtUtils::Command> - -Upgraded from version 1.13 to 1.16. - -=item C<ExtUtils::Constant> - -Upgraded from version 0.2 to 0.22. - -=item C<ExtUtils::Install> - -Upgraded from version 1.44 to 1.55. - -=item C<ExtUtils::MakeMaker> - -Upgraded from version 6.42 to 6.56. - -=item C<ExtUtils::Manifest> - -Upgraded from version 1.51_01 to 1.57. - -=item C<ExtUtils::ParseXS> - -Upgraded from version 2.18_02 to 2.21. - -=item C<File::Fetch> - -Upgraded from version 0.14 to 0.24. - -=item C<File::Path> - -Upgraded from version 2.04 to 2.08_01. - -=item C<File::Temp> - -Upgraded from version 0.18 to 0.22. - -=item C<Filter::Simple> - -Upgraded from version 0.82 to 0.84. - -=item C<Filter::Util::Call> - -Upgraded from version 1.07 to 1.08. - -=item C<Getopt::Long> - -Upgraded from version 2.37 to 2.38. - -=item C<IO> - -Upgraded from version 1.23_01 to 1.25_02. - -=item C<IO::Zlib> - -Upgraded from version 1.07 to 1.10. - -=item C<IPC::Cmd> - -Upgraded from version 0.40_1 to 0.54. - -=item C<IPC::SysV> - -Upgraded from version 1.05 to 2.01. - -=item C<Locale::Maketext> - -Upgraded from version 1.12 to 1.14. - -=item C<Locale::Maketext::Simple> - -Upgraded from version 0.18 to 0.21. - -=item C<Log::Message> - -Upgraded from version 0.01 to 0.02. - -=item C<Log::Message::Simple> - -Upgraded from version 0.04 to 0.06. - -=item C<Math::BigInt> - -Upgraded from version 1.88 to 1.89_01. - -=item C<Math::BigInt::FastCalc> - -Upgraded from version 0.16 to 0.19. - -=item C<Math::BigRat> - -Upgraded from version 0.21 to 0.24. - -=item C<Math::Complex> - -Upgraded from version 1.37 to 1.56. - -=item C<Memoize> - -Upgraded from version 1.01_02 to 1.01_03. - -=item C<MIME::Base64> - -Upgraded from version 3.07_01 to 3.08. - -=item C<Module::Build> - -Upgraded from version 0.2808_01 to 0.3603. - -=item C<Module::CoreList> - -Upgraded from version 2.12 to 2.29. - -=item C<Module::Load> - -Upgraded from version 0.12 to 0.16. - -=item C<Module::Load::Conditional> - -Upgraded from version 0.22 to 0.34. - -=item C<Module::Loaded> - -Upgraded from version 0.01 to 0.06. - -=item C<Module::Pluggable> - -Upgraded from version 3.6 to 3.9. - -=item C<Net::Ping> - -Upgraded from version 2.33 to 2.36. - -=item C<NEXT> - -Upgraded from version 0.60_01 to 0.64. - -=item C<Object::Accessor> - -Upgraded from version 0.32 to 0.36. - -=item C<Package::Constants> - -Upgraded from version 0.01 to 0.02. - -=item C<PerlIO> - -Upgraded from version 1.04 to 1.06. - -=item C<Pod::Parser> - -Upgraded from version 1.35 to 1.37. - -=item C<Pod::Perldoc> - -Upgraded from version 3.14_02 to 3.15_02. - -=item C<Pod::Plainer> - -Upgraded from version 0.01 to 1.02. - -NOTE: C<Pod::Plainer> is deprecated and may be removed from a future -version of Perl. - -=item C<Pod::Simple> - -Upgraded from version 3.05 to 3.13. - -=item C<Safe> - -Upgraded from version 2.12 to 2.22. - -=item C<SelfLoader> - -Upgraded from version 1.11 to 1.17. - -=item C<Storable> - -Upgraded from version 2.18 to 2.22. - -=item C<Switch> - -Upgraded from version 2.13 to 2.16. - -NOTE: C<Switch> is deprecated and may be removed from a future version -of Perl. - -=item C<Sys::Syslog> - -Upgraded from version 0.22 to 0.27. - -=item C<Term::ANSIColor> - -Upgraded from version 1.12 to 2.02. - -=item C<Term::UI> - -Upgraded from version 0.18 to 0.20. - -=item C<Test> - -Upgraded from version 1.25 to 1.25_02. - -=item C<Test::Harness> - -Upgraded from version 2.64 to 3.17. - -=item C<Test::Simple> - -Upgraded from version 0.72 to 0.94. - -=item C<Text::Balanced> - -Upgraded from version 2.0.0 to 2.02. - -=item C<Text::ParseWords> - -Upgraded from version 3.26 to 3.27. - -=item C<Text::Soundex> - -Upgraded from version 3.03 to 3.03_01. - -=item C<Thread::Queue> - -Upgraded from version 2.00 to 2.11. - -=item C<Thread::Semaphore> - -Upgraded from version 2.01 to 2.09. - -=item C<Tie::RefHash> - -Upgraded from version 1.37 to 1.38. - -=item C<Time::HiRes> - -Upgraded from version 1.9711 to 1.9719. - -=item C<Time::Local> - -Upgraded from version 1.18 to 1.1901_01. - -=item C<Time::Piece> - -Upgraded from version 1.12 to 1.15. - -=item C<Unicode::Collate> - -Upgraded from version 0.52 to 0.52_01. - -=item C<Unicode::Normalize> - -Upgraded from version 1.02 to 1.03. - -=item C<Win32> - -Upgraded from version 0.34 to 0.39. - -=item C<Win32API::File> - -Upgraded from version 0.1001_01 to 0.1101. - -=item C<XSLoader> - -Upgraded from version 0.08 to 0.10. - -=back - -=head2 Removed Modules and Pragmata - -=over 4 - -=item C<attrs> - -Removed from the Perl core. Prior version was 1.02. - -=item C<CPAN::API::HOWTO> - -Removed from the Perl core. Prior version was 'undef'. - -=item C<CPAN::DeferedCode> - -Removed from the Perl core. Prior version was 5.50. - -=item C<CPANPLUS::inc> - -Removed from the Perl core. Prior version was 'undef'. - -=item C<DCLsym> - -Removed from the Perl core. Prior version was 1.03. - -=item C<ExtUtils::MakeMaker::bytes> - -Removed from the Perl core. Prior version was 6.42. - -=item C<ExtUtils::MakeMaker::vmsish> - -Removed from the Perl core. Prior version was 6.42. - -=item C<Stdio> - -Removed from the Perl core. Prior version was 2.3. - -=item C<Test::Harness::Assert> - -Removed from the Perl core. Prior version was 0.02. - -=item C<Test::Harness::Iterator> - -Removed from the Perl core. Prior version was 0.02. - -=item C<Test::Harness::Point> - -Removed from the Perl core. Prior version was 0.01. - -=item C<Test::Harness::Results> - -Removed from the Perl core. Prior version was 0.01. - -=item C<Test::Harness::Straps> - -Removed from the Perl core. Prior version was 0.26_01. - -=item C<Test::Harness::Util> - -Removed from the Perl core. Prior version was 0.01. - -=item C<XSSymSet> - -Removed from the Perl core. Prior version was 1.1. - -=back - -=head2 Deprecated Modules and Pragmata - -See L</Deprecated Modules> above. - - -=head1 Documentation - -=head2 New Documentation - -=over 4 - -=item * - -L<perlhaiku> contains instructions on how to build perl for the Haiku -platform. - -=item * - -L<perlmroapi> describes the new interface for pluggable Method Resolution -Orders. - -=item * - -L<perlperf>, 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> describes how to access the perl source using the I<git> -version control system. - -=item * - -L<perlpolicy> extends the "Social contract about contributed modules" into -the beginnings of a document on Perl porting policies. - -=back - -=head2 Changes to Existing Documentation - - -=over - -=item * - -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. - -=item * - -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>. - -=item * - -The syntax C<unless (EXPR) BLOCK else BLOCK> is now documented as valid, -as is the syntax C<unless (EXPR) BLOCK elsif (EXPR) BLOCK ... else -BLOCK>, although actually using the latter may not be the best idea for -the readability of your source code. - -=item * - -Documented -X overloading. - -=item * - -Documented that C<when()> treats specially most of the filetest operators - -=item * - -Documented C<when> as a syntax modifier. - -=item * - -Eliminated "Old Perl threads tutorial", which described 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 notice. - -=item * - -Security contact information is now part of L<perlsec>. - -=item * - -A significant fraction of the core documentation has been updated to -clarify the behavior of Perl's Unicode handling. - -Much of the remaining core documentation has been reviewed and edited -for clarity, consistent use of language, and to fix the spelling of Tom -Christiansen's name. - -=item * - -The Pod specification (L<perlpodspec>) has been updated to bring the -specification in line with modern usage already supported by most Pod -systems. A parameter string may now follow the format name in a -"begin/end" region. Links to URIs with a text description are now -allowed. The usage of C<LE<lt>"section"E<gt>> has been marked as -deprecated. - -=item * - -L<if.pm|if> has been documented in L<perlfunc/use> as a means to get -conditional loading of modules despite the implicit BEGIN block around -C<use>. - -=item * - -The documentation for C<$1> in perlvar.pod has been clarified. - -=item * - -C<\N{U+I<code point>}> is now documented. - -=back - -=head1 Selected Performance Enhancements - -=over 4 - -=item * - -A new internal cache means that C<isa()> will often be faster. - -=item * - -The implementation of C<C3> Method Resolution Order has been -optimised - linearisation for classes with single inheritance is 40% -faster. Performance for multiple inheritance is unchanged. - -=item * - -Under C<use locale>, the locale-relevant information is now cached on -read-only values, such as the list returned by C<keys %hash>. This makes -operations such as C<sort keys %hash> in the scope of C<use locale> -much faster. - -=item * - -Empty C<DESTROY> methods are no longer called. - -=item * - -C<Perl_sv_utf8_upgrade()> is now faster. - -=item * - -C<keys> on empty hash is now faster. - -=item * - -C<if (%foo)> has been optimized to be faster than C<if (keys %foo)>. - -=item * - -The string repetition operator (C<$str x $num>) is now several times -faster when C<$str> has length one or C<$num> is large. - -=item * - -Reversing an array to itself (as in C<@a = reverse @a>) in void context -now happens in-place and is several orders of magnitude faster than -it used to be. It will also preserve non-existent elements whenever -possible, i.e. for non magical arrays or tied arrays with C<EXISTS> -and C<DELETE> methods. - -=back - -=head1 Installation and Configuration Improvements - -=over 4 - -=item * - -L<perlapi>, L<perlintern>, L<perlmodlib> and L<perltoc> are now all -generated at build time, rather than being shipped as part of the release. - -=item * - -If C<vendorlib> and C<vendorarch> are the same, then they are only added -to C<@INC> once. - -=item * - -C<$Config{usedevel}> and the C-level C<PERL_USE_DEVEL> are now defined if -perl is built with C<-Dusedevel>. - -=item * - -F<Configure> will enable use of C<-fstack-protector>, to provide protection -against stack-smashing attacks, if the compiler supports it. - -=item * - -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. - -=item * - -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>. - -=item * - -Perl now supports SystemTap's C<dtrace> compatibility layer and an -issue with linking C<miniperl> has been fixed in the process. - -=item * - -perldoc now uses C<less -R> instead of C<less> for improved behaviour -in the face of C<groff>'s new usage of ANSI escape codes. - -=item * - - -C<perl -V> now reports use of the compile-time options C<USE_PERL_ATOF> and -C<USE_ATTRIBUTES_FOR_PERLIO>. - -=item * - -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>. - -=back - -=head1 Internal Changes - -Each release of Perl sees numerous internal changes which shouldn't -affect day to day usage but may still be notable for developers working -with Perl's source code. - -=over - -=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 * - -The internal structure of the dual-life modules traditionally found in -the F<lib/> and F<ext/> directories in the perl source has changed -significantly. Where possible, dual-lifed modules have been extracted -from F<lib/> and F<ext/>. - -Dual-lifed modules maintained by Perl's developers as part of the Perl -core now live in F<dist/>. Dual-lifed modules maintained primarily on -CPAN now live in F<cpan/>. When reporting a bug in a module located -under F<cpan/>, please send your bug report directly to the module's -bug tracker or author, rather than Perl's bug tracker. - -=item * - -C<\N{...}> now compiles better, always forces UTF-8 internal representation - -Perl's developers have fixed several problems with the recognition of -C<\N{...}> constructs. As part of this, perl will store any scalar -or regex containing C<\N{I<name>}> or C<\N{U+I<code point>}> in its -definition in UTF-8 format. (This was true previously for all occurrences -of C<\N{I<name>}> that did not use a custom translator, but now it's -always true.) - -=item * - -Perl_magic_setmglob now knows about globs, fixing RT #71254. - -=item * - -C<SVt_RV> no longer exists. RVs are now stored in IVs. - -=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> 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> now calls 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 * - -Perl now exports the functions C<PerlIO_find_layer> and C<PerlIO_list_alloc>. - -=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 dereference 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 * - -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 Testing - -=head2 Testing improvements - -=over 4 - -=item 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. - -=item Test harness flexibility - -It's now possible to override C<PERL5OPT> and friends in F<t/TEST> - -=item Test watchdog - -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. - - -=back - -=head2 New Tests - -Perl's developers have added a number of new tests to the core. -In addition to the items listed below, many modules updated from CPAN -incorporate new tests. - -=over 4 - -=item * - -Significant cleanups to core tests to ensure that language and -interpreter features are not used before they're tested. - -=item * - -C<make test_porting> now runs a number of important pre-commit checks -which might be of use to anyone working on the Perl core. - -=item * - -F<t/porting/podcheck.t> automatically checks the well-formedness of -POD found in all .pl, .pm and .pod files in the F<MANIFEST>, other than in -dual-lifed modules which are primarily maintained outside the Perl core. - -=item * - -F<t/porting/manifest.t> now tests that all files listed in MANIFEST -are present. - -=item * - -F<t/op/while_readdir.t> tests that a bare readdir in while loop sets $_. - -=item * - -F<t/comp/retainedlines.t> checks that the debugger can retain source -lines from C<eval>. - -=item * - -F<t/io/perlio_fail.t> checks that bad layers fail. - -=item * - -F<t/io/perlio_leaks.t> checks that PerlIO layers are not leaking. - -=item * - -F<t/io/perlio_open.t> checks that certain special forms of open work. - -=item * - -F<t/io/perlio.t> includes general PerlIO tests. - -=item * - -F<t/io/pvbm.t> checks that there is no unexpected interaction between -the internal types C<PVBM> and C<PVGV>. - -=item * - -F<t/mro/package_aliases.t> checks that mro works properly in the presence -of aliased packages. - -=item * - -F<t/op/dbm.t> tests C<dbmopen> and C<dbmclose>. - -=item * - -F<t/op/index_thr.t> tests the interaction of C<index> and threads. - -=item * - -F<t/op/pat_thr.t> tests the interaction of esoteric patterns and threads. - -=item * - -F<t/op/qr_gc.t> tests that C<qr> doesn't leak. - -=item * - -F<t/op/reg_email_thr.t> tests the interaction of regex recursion and threads. - -=item * - -F<t/op/regexp_qr_embed_thr.t> tests the interaction of patterns with -embedded C<qr//> and threads. - -=item * - -F<t/op/regexp_unicode_prop.t> tests Unicode properties in regular -expressions. - -=item * - -F<t/op/regexp_unicode_prop_thr.t> tests the interaction of Unicode -properties and threads. - -=item * - -F<t/op/reg_nc_tie.t> tests the tied methods of C<Tie::Hash::NamedCapture>. - -=item * - -F<t/op/reg_posixcc.t> checks that POSIX character classes behave -consistently. - -=item * - -F<t/op/re.t> checks that exportable C<re> functions in F<universal.c> work. - -=item * - -F<t/op/setpgrpstack.t> checks that C<setpgrp> works. - -=item * - -F<t/op/substr_thr.t> tests the interaction of C<substr> and threads. - -=item * - -F<t/op/upgrade.t> checks that upgrading and assigning scalars works. - -=item * - -F<t/uni/lex_utf8.t> checks that Unicode in the lexer works. - -=item * - -F<t/uni/tie.t> checks that Unicode and C<tie> work. - -=item * - -F<t/comp/final_line_num.t> tests whether line numbers are correct at EOF - -=item * - -F<t/comp/form_scope.t> tests format scoping. - -=item * - -F<t/comp/line_debug.t> tests whether C<< @{"_<$file"} >> works. - -=item * - -F<t/op/filetest_t.t> tests if -t file test works. - -=item * - -F<t/op/qr.t> tests C<qr>. - -=item * - -F<t/op/utf8cache.t> tests malfunctions of the utf8 cache. - -=item * - -F<t/re/uniprops.t> test unicodes C<\p{}> regex constructs. - -=item * - -F<t/op/filehandle.t> tests some suitably portable filetest operators -to check that they work as expected, particularly in the light of some -internal changes made in how filehandles are blessed. - -=item * - -F<t/op/time_loop.t> tests that unix times greater than C<2**63>, which -can now be handed to C<gmtime> and C<localtime>, do not cause an internal -overflow or an excessively long loop. - -=back - - -=head1 New or Changed Diagnostics - -=head2 New Diagnostics - -=over - -=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 * - -Perl 5.12 provides a number of new diagnostic messages to help you write -better code. See L<perldiag> for details of these new messages. - -=over 4 - -=item * - -C<Bad plugin affecting keyword '%s'> - -=item * - -C<gmtime(%.0f) too large> - -=item * - -C<Lexing code attempted to stuff non-Latin-1 character into Latin-1 input> - -=item * - -C<Lexing code internal error (%s)> - -=item * - -C<localtime(%.0f) too large> - -=item * - -C<Overloaded dereference did not return a reference> - -=item * - -C<Overloaded qr did not return a REGEXP> - -=item * - -C<Perl_pmflag() is deprecated, and will be removed from the XS API> - -=item * - -C<lvalue attribute ignored after the subroutine has been defined> - -This new warning is issued when one attempts to mark a subroutine as -lvalue after it has been defined. - -=item * - -Perl now warns you if C<++> or C<--> are unable to change the value -because it's beyond the limit of representation. - -This uses a new warnings category: "imprecision". - -=item * - -C<lc>, C<uc>, C<lcfirst>, and C<ucfirst> warn when passed undef. - -=item * - -C<Show constant in "Useless use of a constant in void context"> - -=item * - -C<Prototype after '%s'> - -=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 * - -The fatal error C<Malformed UTF-8 returned by \N> is now produced if the -C<charnames> handler returns malformed UTF-8. - -=item * - -If an unresolved named character or sequence was encountered when -compiling a regex pattern then the fatal error C<\N{NAME} must be resolved -by the lexer> is now produced. This can happen, for example, when using a -single-quotish context like C<$re = '\N{SPACE}'; /$re/;>. See L<perldiag> -for more examples of how the lexer can get bypassed. - -=item * - -C<Invalid hexadecimal number in \N{U+...}> is a new fatal error -triggered when the character constant represented by C<...> is not a -valid hexadecimal number. - -=item * - -The new meaning of C<\N> as C<[^\n]> is not valid in a bracketed character -class, just like C<.> in a character class loses its special meaning, -and will cause the fatal error C<\N in a character class must be a named -character: \N{...}>. - -=item * - -The rules on what is legal for the C<...> in C<\N{...}> have been -tightened up so that unless the C<...> begins with an alphabetic -character and continues with a combination of alphanumerics, dashes, -spaces, parentheses or colons then the warning C<Deprecated character(s) -in \N{...} starting at '%s'> is now issued. - -=item * - -The warning C<Using just the first characters returned by \N{}> will -be issued if the C<charnames> handler returns a sequence of characters -which exceeds the limit of the number of characters that can be used. The -message will indicate which characters were used and which were discarded. - -=back - -=back - -=head2 Changed Diagnostics - -A number of existing diagnostic messages have been improved or corrected: - -=over - -=item * - -A new warning category C<illegalproto> allows finer-grained control of -warnings around function prototypes. - -The two warnings: - -=over - -=item C<Illegal character in prototype for %s : %s> - -=item C<Prototype after '%c' for %s : %s> - -=back - -have been moved from the C<syntax> top-level warnings category into a new -first-level category, C<illegalproto>. These two warnings are currently -the only ones emitted during parsing of an invalid/illegal prototype, -so one can now use - - no warnings 'illegalproto'; - -to suppress only those, but not other syntax-related warnings. Warnings -where prototypes are changed, ignored, or not met are still in the -C<prototype> category as before. - -=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. - -=item * - -C<Illegal character in prototype> warning is now more precise -when reporting illegal characters after _ - -=item * - -mro merging error messages are now very similar to those produced by -L<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 * - -Perl now explicitly points to C<$.> when it causes an uninitialized -warning for ranges in scalar context. - -=item * - -C<split> now warns when called in void context. - -=item * - -C<printf>-style functions called with too few arguments will now issue the -warning C<"Missing argument in %s"> [perl #71000] - -=item * - -Perl now properly returns a syntax error instead of segfaulting -if C<each>, C<keys>, or C<values> is used without an argument. - -=item * - -C<tell()> now fails properly if called without an argument and when no -previous file was read. - -C<tell()> now returns C<-1>, and sets errno to C<EBADF>, thus restoring -the 5.8.x behaviour. - -=item * - -C<overload> no longer implicitly unsets fallback on repeated 'use -overload' lines. - -=item * - -POSIX::strftime() can now handle Unicode characters in the format string. - -=item * - -The C<syntax> category was removed from 5 warnings that should only be in -C<deprecated>. - -=item * - -Three fatal C<pack>/C<unpack> error messages have been normalized to -C<panic: %s> - -=item * - -C<Unicode character is illegal> has been rephrased to be more accurate - -It now reads C<Unicode non-character is illegal in interchange> and the -perldiag documentation has been expanded a bit. - -=item * - -Currently, all but the first of the several characters that the -C<charnames> handler may return are discarded when used in a regular -expression pattern bracketed character class. If this happens then the -warning C<Using just the first character returned by \N{} in character -class> will be issued. - -=item * - -The warning C<Missing right brace on \N{} or unescaped left brace after -\N. Assuming the latter> will be issued if Perl encounters a C<\N{> -but doesn't find a matching C<}>. In this case Perl doesn't know if it -was mistakenly omitted, or if "match non-newline" followed by "match -a C<{>" was desired. It assumes the latter because that is actually a -valid interpretation as written, unlike the other case. If you meant -the former, you need to add the matching right brace. If you did mean -the latter, you can silence this warning by writing instead C<\N\{>. - -=item * - -C<gmtime> and C<localtime> called with numbers smaller than they can -reliably handle will now issue the warnings C<gmtime(%.0f) too small> -and C<localtime(%.0f) too small>. - -=back - -The following diagnostic messages have been removed: - -=over 4 - -=item * - -C<Runaway format> - -=item * - -C<Can't locate package %s for the parents of %s> - -In general this warning 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> - -=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. -It also now handles C++ style comments (C<//>) properly in enums. - -=item * - -F<perl5db.pl> now supports C<LVALUE> subroutines. Additionally, the -debugger now correctly handles proxy constant subroutines, and -subroutine stubs. - -=item * - -F<perlbug> now uses C<%Module::CoreList::bug_tracker> to print out -upstream bug tracker URLs. If a user identifies a particular module -as the topic of their bug report and we're able to divine the URL for -its upstream bug tracker, perlbug now 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 the upstream author. - -F<perlbug> no longer reports "Message sent" when it hasn't actually sent -the message - -=item * - -F<perlthanks> is a new utility for sending non-bug-reports to the -authors and maintainers of Perl. Getting nothing but bug reports can -become a bit demoralising. If Perl 5.12 works well for you, please try -out F<perlthanks>. It will make the developers smile. - -=item * - -Perl's developers have fixed bugs in F<a2p> having to do with the -C<match()> operator in list context. Additionally, F<a2p> no longer -generates code that uses the C<$[> variable. - -=back - -=head1 Selected Bug Fixes - -=over 4 - -=item * - -U+0FFFF is now a legal character in regular expressions. - -=item * - -pp_qr now always returns a new regexp SV. Resolves RT #69852. - -Instead of returning a(nother) reference to the (pre-compiled) regexp -in the optree, use reg_temp_copy() to create a copy of it, and return a -reference to that. This resolves issues about Regexp::DESTROY not being -called in a timely fashion (the original bug tracked by RT #69852), as -well as bugs related to blessing regexps, and of assigning to regexps, -as described in correspondence added to the ticket. - -It transpires that we also need to undo the SvPVX() sharing when ithreads -cloning a Regexp SV, because mother_re is set to NULL, instead of a -cloned copy of the mother_re. This change might fix bugs with regexps -and threads in certain other situations, but as yet neither tests nor -bug reports have indicated any problems, so it might not actually be an -edge case that it's possible to reach. - -=item * - -Several compilation errors and segfaults when perl was built with C<-Dmad> -were fixed. - -=item * - -Fixes for lexer API changes in 5.11.2 which broke NYTProf's savesrc option. - -=item * - -C<-t> should only return TRUE for file handles connected to a TTY - -The Microsoft C version of C<isatty()> returns TRUE for all character mode -devices, including the F</dev/null>-style "nul" device and printers like -"lpt1". - -=item * - -Fixed a regression caused by commit fafafbaf which caused a panic during -parameter passing [perl #70171] - -=item * - -On systems which in-place edits without backup files, -i'*' now works as -the documentation says it does [perl #70802] - -=item * - -Saving and restoring magic flags no longer loses readonly flag. - -=item * - -The malformed syntax C<grep EXPR LIST> (note the missing comma) no longer -causes abrupt and total failure. - -=item * - -Regular expressions compiled with C<qr{}> literals properly set C<$'> when -matching again. - -=item * - -Using named subroutines with C<sort> should no longer lead to bus errors -[perl #71076] - -=item * - -Numerous bugfixes catch small issues caused by the recently-added Lexer API. - -=item * - -Smart match against C<@_> sometimes gave false negatives. [perl #71078] - -=item * - -C<$@> may now be assigned a read-only value (without error or busting -the stack). - -=item * - -C<sort> called recursively from within an active comparison subroutine no -longer causes a bus error if run multiple times. [perl #71076] - -=item * - -Tie::Hash::NamedCapture::* will not abort if passed bad input (RT #71828) - -=item * - -@_ and $_ no longer leak under threads (RT #34342 and #41138, also -#70602, #70974) - -=item * - -C<-I> on shebang line now adds directories in front of @INC -as documented, and as does C<-I> when specified on the command-line. - -=item * - -C<kill> is now fatal when called on non-numeric process identifiers. -Previously, an C<undef> process identifier would be interpreted as a -request to kill process 0, which would terminate the current process -group on POSIX systems. Since process identifiers are always integers, -killing a non-numeric process is now fatal. - -=item * - -5.10.0 inadvertently disabled an optimisation, which caused a measurable -performance drop in list assignment, such as is often used to assign -function parameters from C<@_>. The optimisation has been re-instated, and -the performance regression fixed. (This fix is also present in 5.10.1) - -=item * - -Fixed memory leak on C<while (1) { map 1, 1 }> [RT #53038]. - -=item * - -Some potential coredumps in PerlIO fixed [RT #57322,54828]. - -=item * - -The debugger now works with lvalue subroutines. - -=item * - -The debugger's C<m> command was broken on modules that defined constants -[RT #61222]. - -=item * - -C<crypt> and string complement could return tainted values for untainted -arguments [RT #59998]. - -=item * - -The C<-i>I<.suffix> command-line switch now recreates the file using -restricted permissions, before changing its mode to match the original -file. This eliminates a potential race condition [RT #60904]. - -=item * - -On some Unix systems, the value in C<$?> 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)*$/ - -=item * - -C<shmget> was limited to a 32 bit segment size on a 64 bit OS [RT #63924]. - -=item * - -Using C<next> or C<last> to exit a C<given> block no longer produces a -spurious warning like the following: - - Exiting given via last at foo.pl line 123 - -=item * - -Assigning a format to a glob could corrupt the format; e.g.: - - *bar=*foo{FORMAT}; # foo format now bad - -=item * - -Attempting to coerce a typeglob to a string or number could cause an -assertion failure. The correct error message is now generated, -C<Can't coerce GLOB to I<$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 * - -Perl now includes previously missing files from the Unicode Character -Database. - -=item * - -Perl now honors C<TMPDIR> when opening an anonymous temporary file. - -=back - - -=head1 Platform Specific Changes - -Perl is incredibly portable. In general, if a platform has a C compiler, -someone has ported Perl to it (or will soon). We're happy to announce -that Perl 5.12 includes support for several new platforms. At the same -time, it's time to bid farewell to some (very) old friends. - -=head2 New Platforms - -=over - -=item Haiku - -Perl's developers have merged patches from Haiku's maintainers. Perl -should now build on Haiku. - -=item MirOS BSD - -Perl should now build on MirOS BSD. - -=back - -=head2 Discontinued Platforms - -=over - -=item Domain/OS - -=item MiNT - -=item Tenon MachTen - -=back - -=head2 Updated Platforms - -=over 4 - -=item AIX - -=over 4 - -=item * - -Removed F<libbsd> for AIX 5L and 6.1. Only C<flock()> was used from -F<libbsd>. - -=item * - -Removed F<libgdbm> for AIX 5L and 6.1 if F<libgdbm> < 1.8.3-5 is -installed. The F<libgdbm> is delivered as an optional package with the -AIX Toolbox. Unfortunately the versions below 1.8.3-5 are broken. - -=item * - -Hints changes mean that AIX 4.2 should work again. - -=back - -=item Cygwin - -=over 4 - -=item * - -Perl now supports IPv6 on Cygwin 1.7 and newer. - -=item * - -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. - -=back - -=item Darwin (Mac OS X) - -=over 4 - -=item * - -Skip testing the be_BY.CP1131 locale on Darwin 10 (Mac OS X 10.6), -as it's still buggy. - -=item * - -Correct infelicities in the regexp used to identify buggy locales -on Darwin 8 and 9 (Mac OS X 10.4 and 10.5, respectively). - -=back - -=item DragonFly BSD - -=over 4 - -=item * - -Fix thread library selection [perl #69686] - -=back - -=item FreeBSD - -=over 4 - -=item * - -The hints files now identify the correct threading libraries on FreeBSD 7 -and later. - -=back - -=item Irix - -=over 4 - -=item * - -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. - -=back - -=item NetBSD - -=over 4 - -=item * - -Hints now supports versions 5.*. - -=back - -=item OpenVMS - -=over 4 - -=item * - -C<-UDEBUGGING> is now the default on VMS. - -Like it has been everywhere else for ages and ages. Also make command-line -selection of -UDEBUGGING and -DDEBUGGING work in configure.com; before -the only way to turn it off was by saying no in answer to the interactive -question. - -=item * - -The default pipe buffer size on VMS has been updated to 8192 on 64-bit -systems. - -=item * - -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. - -=item * - -VMS now supports C<getgrgid>. - -=item * - -Many improvements and cleanups have been made to the VMS file name handling -and conversion code. - -=item * - -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. - -=item * - -C<File::Copy> now detects Unix compatibility mode on VMS. - -=back - -=item Stratus VOS - -=over 4 - -=item * - -Various changes from Stratus have been merged in. - -=back - -=item Symbian - -=over 4 - -=item * - -There is now support for Symbian S60 3.2 SDK and S60 5.0 SDK. - -=back - -=item Windows - -=over 4 - -=item * - -Perl 5.12 supports Windows 2000 and later. The supporting code for -legacy versions of Windows is still included, but will be removed -during the next development cycle. - -=item * - -Initial support for building Perl with MinGW-w64 is now available. - -=item * - -F<perl.exe> now includes a manifest resource to specify the C<trustInfo> -settings for Windows Vista and later. Without this setting Windows -would treat F<perl.exe> as a legacy application and apply various -heuristics like redirecting access to protected file system areas -(like the "Program Files" folder) to the users "VirtualStore" -instead of generating a proper "permission denied" error. - -The manifest resource also requests the Microsoft Common-Controls -version 6.0 (themed controls introduced in Windows XP). Check out the -Win32::VisualStyles module on CPAN to switch back to old style -unthemed controls for legacy applications. - -=item * - -The C<-t> filetest operator now only returns true if the filehandle -is connected to a console window. In previous versions of Perl it -would return true for all character mode devices, including F<NUL> -and F<LPT1>. - -=item * - -The C<-p> filetest operator now works correctly, and the -Fcntl::S_IFIFO constant is defined when Perl is compiled with -Microsoft Visual C. In previous Perl versions C<-p> always -returned a false value, and the Fcntl::S_IFIFO constant -was not defined. - -This bug is specific to Microsoft Visual C and never affected -Perl binaries built with MinGW. - -=item * - -The socket error codes are now more widely supported: The POSIX -module will define the symbolic names, like POSIX::EWOULDBLOCK, -and stringification of socket error codes in $! works as well -now; - - C:\>perl -MPOSIX -E "$!=POSIX::EWOULDBLOCK; say $!" - A non-blocking socket operation could not be completed immediately. - -=item * - -flock() will now set sensible error codes in $!. Previous Perl versions -copied the value of $^E into $!, which caused much confusion. - -=item * - -select() now supports all empty C<fd_set>s more correctly. - -=item * - -C<'.\foo'> and C<'..\foo'> were treated differently than -C<'./foo'> and C<'../foo'> by C<do> and C<require> [RT #63492]. - -=item * - -Improved message window handling means that C<alarm> and C<kill> messages -will no longer be dropped under race conditions. - -=item * - -Various bits of Perl's build infrastructure are no longer converted to -win32 line endings at release time. If this hurts you, please report the -problem with the L<perlbug> program included with perl. - -=back - -=back - - -=head1 Known Problems - -This is a list of some significant unfixed bugs, which are regressions -from either 5.10.x or 5.8.x. - -=over 4 - -=item * - -Some CPANPLUS tests may fail if there is a functioning file -F<../../cpanp-run-perl> outside your build directory. The failure -shouldn't imply there's a problem with the actual functional -software. The bug is already fixed in [RT #74188] and is scheduled for -inclusion in perl-v5.12.1. - -=item * - -C<List::Util::first> misbehaves in the presence of a lexical C<$_> -(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 * - -Some regexes may run much more slowly when run in a child thread compared -with the thread the pattern was compiled into [RT #55600]. - -=item * - -Things like C<"\N{LATIN SMALL LIGATURE FF}" =~ /\N{LATIN SMALL LETTER F}+/> -will appear to hang as they get into a very long running loop [RT #72998]. - -=item * - -Several porters have reported mysterious crashes when Perl's entire -test suite is run after a build on certain Windows 2000 systems. When -run by hand, the individual tests reportedly work fine. - -=back - -=head1 Errata - -=over - -=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; - -=back - -=head1 Acknowledgements - -Perl 5.12.0 represents approximately two years of development since -Perl 5.10.0 and contains over 750,000 lines of changes across over -3,000 files from over 200 authors and committers. - -Perl continues to flourish into its third decade thanks to a vibrant -community of users and developers. The following people are known to -have contributed the improvements that became Perl 5.12.0: - -Aaron Crane, Abe Timmerman, Abhijit Menon-Sen, Abigail, Adam Russell, -Adriano Ferreira, Ævar Arnfjörð Bjarmason, Alan Grover, Alexandr -Ciornii, Alex Davies, Alex Vandiver, Andreas Koenig, Andrew Rodland, -andrew@sundale.net, Andy Armstrong, Andy Dougherty, Jose AUGUSTE-ETIENNE, -Benjamin Smith, Ben Morrow, bharanee rathna, Bo Borgerson, Bo Lindbergh, -Brad Gilbert, Bram, Brendan O'Dea, brian d foy, Charles Bailey, -Chip Salzenberg, Chris 'BinGOs' Williams, Christoph Lamprecht, Chris -Williams, chromatic, Claes Jakobsson, Craig A. Berry, Dan Dascalescu, -Daniel Frederick Crisman, Daniel M. Quinlan, Dan Jacobson, Dan Kogai, -Dave Mitchell, Dave Rolsky, David Cantrell, David Dick, David Golden, -David Mitchell, David M. Syzdek, David Nicol, David Wheeler, Dennis -Kaarsemaker, Dintelmann, Peter, Dominic Dunlop, Dr.Ruud, Duke Leto, -Enrico Sorcinelli, Eric Brine, Father Chrysostomos, Florian Ragwitz, -Frank Wiegand, Gabor Szabo, Gene Sullivan, Geoffrey T. Dairiki, George -Greer, Gerard Goossen, Gisle Aas, Goro Fuji, Graham Barr, Green, Paul, -Hans Dieter Pearcey, Harmen, H. Merijn Brand, Hugo van der Sanden, -Ian Goodacre, Igor Sutton, Ingo Weinhold, James Bence, James Mastros, -Jan Dubois, Jari Aalto, Jarkko Hietaniemi, Jay Hannah, Jerry Hedden, -Jesse Vincent, Jim Cromie, Jody Belka, John E. Malmberg, John Malmberg, -John Peacock, John Peacock via RT, John P. Linderman, John Wright, -Josh ben Jore, Jos I. Boumans, Karl Williamson, Kenichi Ishigaki, Ken -Williams, Kevin Brintnall, Kevin Ryde, Kurt Starsinic, Leon Brocard, -Lubomir Rintel, Luke Ross, Marcel Grünauer, Marcus Holland-Moritz, Mark -Jason Dominus, Marko Asplund, Martin Hasch, Mashrab Kuvatov, Matt Kraai, -Matt S Trout, Max Maischein, Michael Breen, Michael Cartmell, Michael -G Schwern, Michael Witten, Mike Giroux, Milosz Tanski, Moritz Lenz, -Nicholas Clark, Nick Cleaton, Niko Tyni, Offer Kaye, Osvaldo Villalon, -Paul Fenwick, Paul Gaborit, Paul Green, Paul Johnson, Paul Marquess, -Philip Hazel, Philippe Bruhat, Rafael Garcia-Suarez, Rainer Tammer, -Rajesh Mandalemula, Reini Urban, Renée Bäcker, Ricardo Signes, -Ricardo SIGNES, Richard Foley, Rich Rauenzahn, Rick Delaney, Risto -Kankkunen, Robert May, Roberto C. Sanchez, Robin Barker, SADAHIRO -Tomoyuki, Salvador Ortiz Garcia, Sam Vilain, Scott Lanning, Sébastien -Aperghis-Tramoni, Sérgio Durigan Júnior, Shlomi Fish, Simon 'corecode' -Schubert, Sisyphus, Slaven Rezic, Smylers, Steffen Müller, Steffen -Ullrich, Stepan Kasal, Steve Hay, Steven Schubiger, Steve Peters, Tels, -The Doctor, Tim Bunce, Tim Jenness, Todd Rinaldo, Tom Christiansen, -Tom Hukins, Tom Wyant, Tony Cook, Torsten Schoenfeld, Tye McQueen, -Vadim Konovalov, Vincent Pit, Hio YAMASHINA, Yasuhiro Matsumoto, -Yitzchak Scott-Thoennes, Yuval Kogman, Yves Orton, Zefram, Zsban Ambrus - -This is woefully incomplete as it's automatically generated from version -control history. In particular, it doesn't include the names of the -(very much appreciated) contributors who reported issues in previous -versions of Perl that helped make Perl 5.12.0 better. For a more complete -list of all of Perl's historical contributors, please see the C<AUTHORS> -file in the Perl 5.12.0 distribution. - -Our "retired" pumpkings Nicholas Clark and Rafael Garcia-Suarez -deserve special thanks for their brilliant and substantive ongoing -contributions. Nicholas personally authored over 30% of the patches -since 5.10.0. Rafael comes in second in patch authorship with 11%, -but is first by a long shot in committing patches authored by others, -pushing 44% of the commits since 5.10.0 in this category, often after -providing considerable coaching to the patch authors. These statistics -in no way comprise all of their contributions, but express in shorthand -that we couldn't have done it without them. - -Many of the changes included in this version originated in the CPAN -modules included in Perl's core. We're grateful to the entire CPAN -community for helping Perl to flourish. - -=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 L<http://rt.perl.org/perlbug/>. There may also be -information at L<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 -analyzed 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 will 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. - -L<http://dev.perl.org/perl5/errata.html> for a list of issues -found after this release, as well as a list of CPAN modules known -to be incompatible with this release. - -=cut |