PERL5122DELTA(1) Perl Programmers Reference Guide PERL5122DELTA(1)
NAME
perl5122delta - what is new for perl v5.12.2
DESCRIPTION
This document describes differences between the 5.12.1 release and the
5.12.2 release.
If you are upgrading from an earlier major version, such as 5.10.1,
first read perl5120delta, which describes differences between 5.10.0 and
5.12.0, as well as perl5121delta, which describes earlier changes in the
5.12 stable release series.
Incompatible Changes
There are no changes intentionally incompatible with 5.12.1. If any
exist, they are bugs and reports are welcome.
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
New Modules and Pragmata
This release does not introduce any new modules or pragmata.
Pragmata Changes
In the previous release, "no VERSION;" statements triggered a bug which
could cause feature bundles to be loaded and strict mode to be enabled
unintentionally.
Updated Modules
"Carp"
Upgraded from version 1.16 to 1.17.
Carp now detects incomplete caller() overrides and avoids using
bogus @DB::args. To provide backtraces, Carp relies on particular
behaviour of the caller built-in. Carp now detects if other code has
overridden this with an incomplete implementation, and modifies its
backtrace accordingly. Previously incomplete overrides would cause
incorrect values in backtraces (best case), or obscure fatal errors
(worst case)
This fixes certain cases of "Bizarre copy of ARRAY" caused by
modules overriding caller() incorrectly.
"CPANPLUS"
A patch to cpanp-run-perl has been backported from CPANPLUS 0.9004.
This resolves RT #55964
<http://rt.cpan.org/Public/Bug/Display.html?id=55964> and RT #57106
<http://rt.cpan.org/Public/Bug/Display.html?id=57106>, both of which
related to failures to install distributions that use
"Module::Install::DSL".
"File::Glob"
A regression which caused a failure to find "CORE::GLOBAL::glob"
after loading "File::Glob" to crash has been fixed. Now, it
correctly falls back to external globbing via "pp_glob".
"File::Copy"
"File::Copy::copy(FILE, DIR)" is now documented.
"File::Spec"
Upgraded from version 3.31 to 3.31_01.
Several portability fixes were made in "File::Spec::VMS": a colon is
now recognized as a delimiter in native filespecs; caret-escaped
delimiters are recognized for better handling of extended filespecs;
catpath() returns an empty directory rather than the current
directory if the input directory name is empty; abs2rel() properly
handles Unix-style input.
Utility Changes
• perlbug now always gives the reporter a chance to change the email
address it guesses for them.
• perlbug should no longer warn about uninitialized values when using
the "-d" and "-v" options.
Changes to Existing Documentation
• The existing policy on backward-compatibility and deprecation has
been added to perlpolicy, along with definitions of terms like
deprecation.
• "srand" in perlfunc's usage has been clarified.
• The entry for "die" in perlfunc was reorganized to emphasize its
role in the exception mechanism.
• Perl's INSTALL file has been clarified to explicitly state that Perl
requires a C89 compliant ANSI C Compiler.
• IO::Socket's getsockopt() and setsockopt() have been documented.
• alarm()'s inability to interrupt blocking IO on Windows has been
documented.
• Math::TrulyRandom hasn't been updated since 1996 and has been
removed as a recommended solution for random number generation.
• perlrun has been updated to clarify the behaviour of octal flags to
perl.
• To ease user confusion, $# and $*, two special variables that were
removed in earlier versions of Perl have been documented.
• The version of perlfaq shipped with the Perl core has been updated
from the official FAQ version, which is now maintained in the
"briandfoy/perlfaq" branch of the Perl repository at
<git://perl5.git.perl.org/perl.git>.
Installation and Configuration Improvements
Configuration improvements
• The "d_u32align" configuration probe on ARM has been fixed.
Compilation improvements
• An ""incompatible operand types"" error in ternary expressions when
building with "clang" has been fixed.
• Perl now skips setuid "File::Copy" tests on partitions it detects to
be mounted as "nosuid".
Selected Bug Fixes
• A possible segfault in the "T_PRTOBJ" default typemap has been
fixed.
• A possible memory leak when using caller() to set @DB::args has been
fixed.
• Several memory leaks when loading XS modules were fixed.
• unpack() now handles scalar context correctly for %32H and %32u,
fixing a potential crash. split() would crash because the third
item on the stack wasn't the regular expression it expected.
"unpack("%2H", ...)" would return both the unpacked result and the
checksum on the stack, as would "unpack("%2u", ...)". [GH #10257]
<https://github.com/Perl/perl5/issues/10257>
• Perl now avoids using memory after calling free() in pp_require when
there are CODEREFs in @INC.
• A bug that could cause ""Unknown error"" messages when
""call_sv(code, G_EVAL)"" is called from an XS destructor has been
fixed.
• The implementation of the "open $fh, '>' \$buffer" feature now
supports get/set magic and thus tied buffers correctly.
• The "pp_getc", "pp_tell", and "pp_eof" opcodes now make room on the
stack for their return values in cases where no argument was passed
in.
• When matching unicode strings under some conditions inappropriate
backtracking would result in a "Malformed UTF-8 character (fatal)"
error. This should no longer occur. See [GH #10434]
<https://github.com/Perl/perl5/issues/10434>
Platform Specific Notes
AIX
• README.aix has been updated with information about the XL C/C++ V11
compiler suite.
Windows
• When building Perl with the mingw64 x64 cross-compiler "incpath",
"libpth", "ldflags", "lddlflags" and "ldflags_nolargefiles" values
in Config.pm and Config_heavy.pl were not previously being set
correctly because, with that compiler, the include and lib
directories are not immediately below "$(CCHOME)".
VMS
• git_version.h is now installed on VMS. This was an oversight in
v5.12.0 which caused some extensions to fail to build.
• Several memory leaks in stat() have been fixed.
• A memory leak in Perl_rename() due to a double allocation has been
fixed.
• A memory leak in vms_fid_to_name() (used by realpath() and
realname()) has been fixed.
Acknowledgements
Perl 5.12.2 represents approximately three months of development since
Perl 5.12.1 and contains approximately 2,000 lines of changes across 100
files from 36 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 5.12.2:
Abigail, Ævar Arnfjörð Bjarmason, Ben Morrow, brian d foy, Brian
Phillips, Chas. Owens, Chris 'BinGOs' Williams, Chris Williams, Craig A.
Berry, Curtis Jewell, Dan Dascalescu, David Golden, David Mitchell,
Father Chrysostomos, Florian Ragwitz, George Greer, H.Merijn Brand, Jan
Dubois, Jesse Vincent, Jim Cromie, Karl Williamson, Lars Dɪᴇᴄᴋᴏᴡ 迪拉斯,
Leon Brocard, Maik Hentsche, Matt S Trout, Nicholas Clark, Rafael
Garcia-Suarez, Rainer Tammer, Ricardo Signes, Salvador Ortiz Garcia,
Sisyphus, Slaven Rezic, Steffen Mueller, Tony Cook, Vincent Pit and Yves
Orton.
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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