PERL5121DELTA(1) Perl Programmers Reference Guide PERL5121DELTA(1)
NAME
perl5121delta - what is new for perl v5.12.1
DESCRIPTION
This document describes differences between the 5.12.0 release and the
5.12.1 release.
If you are upgrading from an earlier release such as 5.10.1, first read
perl5120delta, which describes differences between 5.10.0 and 5.12.0.
Incompatible Changes
There are no changes intentionally incompatible with 5.12.0. If any
incompatibilities with 5.12.0 exist, they are bugs. Please report them.
Core Enhancements
Other than the bug fixes listed below, there should be no user-visible
changes to the core language in this release.
Modules and Pragmata
Pragmata Changes
• We fixed exporting of "is_strict" and "is_lax" from version.
These were being exported with a wrapper that treated them as method
calls, which caused them to fail. They are just functions, are
documented as such, and should never be subclassed, so this patch
just exports them directly as functions without the wrapper.
Updated Modules
• We upgraded CGI to version 3.49 to incorporate fixes for regressions
introduced in the release we shipped with Perl 5.12.0.
• We upgraded Pod::Simple to version 3.14 to get an improvement to
\C\<\< \>\> parsing.
• We made a small fix to the CPANPLUS test suite to fix an occasional
spurious test failure.
• We upgraded Safe to version 2.27 to wrap coderefs returned by
reval() and rdo().
Changes to Existing Documentation
• We added the new maintenance release policy to perlpolicy
• We've clarified the multiple-angle-bracket construct in the spec for
POD in perlpodspec
• We added a missing explanation for a warning about ":=" to perldiag
• We removed a false claim in perlunitut that all text strings are
Unicode strings in Perl.
• We updated the GitHub mirror link in perlrepository to mirrors/perl,
not github/perl
• We fixed a minor error in perl5114delta.
• We replaced a mention of the now-obsolete Switch with given/when.
• We improved documentation about $sitelibexp/sitecustomize.pl in
perlrun.
• We corrected perlmodlib which had unintentionally omitted a number
of modules.
• We updated the documentation for 'require' in perlfunc relating to
putting Perl code in @INC.
• We reinstated some erroneously-removed documentation about quotemeta
in perlfunc.
• We fixed an a2p example in perlutil.
• We filled in a blank in perlport with the release date of Perl 5.12.
• We fixed broken links in a number of perldelta files.
• The documentation for Carp incorrectly stated that the
$Carp::Verbose variable makes cluck generate stack backtraces.
• We fixed a number of typos in Pod::Functions
• We improved documentation of case-changing functions in perlfunc
• We corrected perlgpl to contain the correct version of the GNU
General Public License.
Testing
Testing Improvements
• t/op/sselect.t is now less prone to clock jitter during timing
checks on Windows.
sleep() time on Win32 may be rounded down to multiple of the clock
tick interval.
• lib/blib.t and lib/locale.t: Fixes for test failures on Darwin/PPC
• perl5db.t: Fix for test failures when "Term::ReadLine::Gnu" is
installed.
Installation and Configuration Improvements
Configuration improvements
• We updated INSTALL with notes about how to deal with broken dbm.h on
OpenSUSE (and possibly other platforms)
Bug Fixes
• A bug in how we process filetest operations could cause a segfault.
Filetests don't always expect an op on the stack, so we now use TOPs
only if we're sure that we're not stat'ing the _ filehandle. This
is indicated by OPf_KIDS (as checked in ck_ftst).
See also: <https://github.com/Perl/perl5/issues/10335>
• When deparsing a nextstate op that has both a change of package
(relative to the previous nextstate) and a label, the package
declaration is now emitted first, because it is syntactically
impermissible for a label to prefix a package declaration.
• XSUB.h now correctly redefines fgets under PERL_IMPLICIT_SYS
See also: <http://rt.cpan.org/Public/Bug/Display.html?id=55049>
• utf8::is_utf8 now respects GMAGIC (e.g. $1)
• XS code using fputc() or fputs(): on Windows could cause an error
due to their arguments being swapped.
See also: <https://github.com/Perl/perl5/issues/10156>
• We fixed a small bug in lex_stuff_pvn() that caused spurious syntax
errors in an obscure situation. It happened when stuffing was
performed on the last line of a file and the line ended with a
statement that lacked a terminating semicolon.
See also: <https://github.com/Perl/perl5/issues/10273>
• We fixed a bug that could cause \N{} constructs followed by a single
. to be parsed incorrectly.
See also: <https://github.com/Perl/perl5/issues/10367>
• We fixed a bug that caused when(scalar) without an argument not to
be treated as a syntax error.
See also: <https://github.com/Perl/perl5/issues/10287>
• We fixed a regression in the handling of labels immediately before
string evals that was introduced in Perl 5.12.0.
See also: <https://github.com/Perl/perl5/issues/10301>
• We fixed a regression in case-insensitive matching of folded
characters in regular expressions introduced in Perl 5.10.1.
See also: <https://github.com/Perl/perl5/issues/10193>
Platform Specific Notes
HP-UX
• Perl now allows -Duse64bitint without promoting to use64bitall on
HP-UX
AIX
• Perl now builds on AIX 4.2
The changes required work around AIX 4.2s' lack of support for IPv6,
and limited support for POSIX sigaction().
FreeBSD 7
• FreeBSD 7 no longer contains /usr/bin/objformat. At build time, Perl
now skips the objformat check for versions 7 and higher and assumes
ELF.
VMS
• It's now possible to build extensions on older (pre 7.3-2) VMS
systems.
DCL symbol length was limited to 1K up until about seven years or so
ago, but there was no particularly deep reason to prevent those
older systems from configuring and building Perl.
• We fixed the previously-broken "-Uuseperlio" build on VMS.
We were checking a variable that doesn't exist in the non-default
case of disabling perlio. Now we only look at it when it exists.
• We fixed the -Uuseperlio command-line option in configure.com.
Formerly it only worked if you went through all the questions
interactively and explicitly answered no.
Known Problems
• "List::Util::first" misbehaves in the presence of a lexical $_
(typically introduced by "my $_" or implicitly by "given"). The
variable which gets set for each iteration is the package variable
$_, not the lexical $_.
A similar issue may occur in other modules that provide functions
which take a block as their first argument, like
foo { ... $_ ...} list
See also: <https://github.com/Perl/perl5/issues/9798>
• "Module::Load::Conditional" and "version" have an unfortunate
interaction which can cause "CPANPLUS" to crash when it encounters
an unparseable version string. Upgrading to "CPANPLUS" 0.9004 or
"Module::Load::Conditional" 0.38 from CPAN will resolve this issue.
Acknowledgements
Perl 5.12.1 represents approximately four weeks of development since
Perl 5.12.0 and contains approximately 4,000 lines of changes across 142
files from 28 authors.
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 5.12.1:
Ævar Arnfjörð Bjarmason, Chris Williams, chromatic, Craig A. Berry,
David Golden, Father Chrysostomos, Florian Ragwitz, Frank Wiegand, Gene
Sullivan, Goro Fuji, H.Merijn Brand, James E Keenan, Jan Dubois, Jesse
Vincent, Josh ben Jore, Karl Williamson, Leon Brocard, Michael Schwern,
Nga Tang Chan, Nicholas Clark, Niko Tyni, Philippe Bruhat, Rafael
Garcia-Suarez, Ricardo Signes, Steffen Mueller, Todd Rinaldo, Vincent
Pit and Zefram.
Reporting Bugs
If you find what you think is a bug, you might check the articles
recently posted to the comp.lang.perl.misc newsgroup and the perl bug
database at http://rt.perl.org/perlbug/ . There may also be information
at http://www.perl.org/ , the Perl Home Page.
If you believe you have an unreported bug, please run the 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 "perl -V", will be sent off to perlbug@perl.org to be analysed by the
Perl porting team.
If the bug you are reporting has security implications, which make it
inappropriate to send to a publicly archived mailing list, then please
send it to perl5-security-report@perl.org. This points to a closed
subscription unarchived mailing list, which includes all the core
committers, who 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.
SEE ALSO
The Changes file for an explanation of how to view exhaustive details on
what changed.
The INSTALL file for how to build Perl.
The README file for general stuff.
The Artistic and Copying files for copyright information.
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