PERL5181DELTA(1) Perl Programmers Reference Guide PERL5181DELTA(1)
NAME
perl5181delta - what is new for perl v5.18.1
DESCRIPTION
This document describes differences between the 5.18.0 release and the
5.18.1 release.
If you are upgrading from an earlier release such as 5.16.0, first read
perl5180delta, which describes differences between 5.16.0 and 5.18.0.
Incompatible Changes
There are no changes intentionally incompatible with 5.18.0 If any
exist, they are bugs, and we request that you submit a report. See
"Reporting Bugs" below.
Modules and Pragmata
Updated Modules and Pragmata
• B has been upgraded from 1.42 to 1.42_01, fixing bugs related to
lexical subroutines.
• Digest::SHA has been upgraded from 5.84 to 5.84_01, fixing a
crashing bug. [RT #118649]
• Module::CoreList has been upgraded from 2.89 to 2.96.
Platform Support
Platform-Specific Notes
AIX A rarely-encountered configuration bug in the AIX hints file has
been corrected.
MidnightBSD
After a patch to the relevant hints file, perl should now build
correctly on MidnightBSD 0.4-RELEASE.
Selected Bug Fixes
• Starting in v5.18.0, a construct like "/[#](?{})/x" would have its
"#" incorrectly interpreted as a comment. The code block would be
skipped, unparsed. This has been corrected.
• A number of memory leaks related to the new, experimental regexp
bracketed character class feature have been plugged.
• The OP allocation code now returns correctly aligned memory in all
cases for "struct pmop". Previously it could return memory only
aligned to a 4-byte boundary, which is not correct for an ithreads
build with 64 bit IVs on some 32 bit platforms. Notably, this caused
the build to fail completely on sparc GNU/Linux. [RT #118055]
• The debugger's "man" command been fixed. It was broken in the
v5.18.0 release. The "man" command is aliased to the names "doc" and
"perldoc" - all now work again.
• @_ is now correctly visible in the debugger, fixing a regression
introduced in v5.18.0's debugger. [RT #118169]
• Fixed a small number of regexp constructions that could either fail
to match or crash perl when the string being matched against was
allocated above the 2GB line on 32-bit systems. [RT #118175]
• Perl v5.16 inadvertently introduced a bug whereby calls to XSUBs
that were not visible at compile time were treated as lvalues and
could be assigned to, even when the subroutine was not an lvalue
sub. This has been fixed. [perl #117947]
• Perl v5.18 inadvertently introduced a bug whereby dual-vars (i.e.
variables with both string and numeric values, such as $! ) where
the truthness of the variable was determined by the numeric value
rather than the string value. [RT #118159]
• Perl v5.18 inadvertently introduced a bug whereby interpolating
mixed up- and down-graded UTF-8 strings in a regex could result in
malformed UTF-8 in the pattern: specifically if a downgraded
character in the range "\x80..\xff" followed a UTF-8 string, e.g.
utf8::upgrade( my $u = "\x{e5}");
utf8::downgrade(my $d = "\x{e5}");
/$u$d/
[perl #118297].
• Lexical constants ("my sub a() { 42 }") no longer crash when
inlined.
• Parameter prototypes attached to lexical subroutines are now
respected when compiling sub calls without parentheses. Previously,
the prototypes were honoured only for calls with parentheses. [RT
#116735]
• Syntax errors in lexical subroutines in combination with calls to
the same subroutines no longer cause crashes at compile time.
• The dtrace sub-entry probe now works with lexical subs, instead of
crashing [perl #118305].
• Undefining an inlinable lexical subroutine (my sub foo() { 42 }
undef &foo) would result in a crash if warnings were turned on.
• Deep recursion warnings no longer crash lexical subroutines. [RT
#118521]
Acknowledgements
Perl 5.18.1 represents approximately 2 months of development since Perl
5.18.0 and contains approximately 8,400 lines of changes across 60 files
from 12 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 5.18.1:
Chris 'BinGOs' Williams, Craig A. Berry, Dagfinn Ilmari Mannsåker, David
Mitchell, Father Chrysostomos, Karl Williamson, Lukas Mai, Nicholas
Clark, Peter Martini, Ricardo Signes, Shlomi Fish, Tony Cook.
The list above is almost certainly incomplete as it is automatically
generated from version control history. In particular, it does not
include the names of the (very much appreciated) contributors who
reported issues to the Perl bug tracker.
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.
For a more complete list of all of Perl's historical contributors,
please see the AUTHORS file in the Perl source distribution.
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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