PERL586DELTA(1) Perl Programmers Reference Guide PERL586DELTA(1)
NAME
perl586delta - what is new for perl v5.8.6
DESCRIPTION
This document describes differences between the 5.8.5 release and the
5.8.6 release.
Incompatible Changes
There are no changes incompatible with 5.8.5.
Core Enhancements
The perl interpreter is now more tolerant of UTF-16-encoded scripts.
On Win32, Perl can now use non-IFS compatible LSPs, which allows Perl to
work in conjunction with firewalls such as McAfee Guardian. For full
details see the file README.win32, particularly if you're running Win95.
Modules and Pragmata
• With the "base" pragma, an intermediate class with no fields used to
messes up private fields in the base class. This has been fixed.
• Cwd upgraded to version 3.01 (as part of the new PathTools
distribution)
• Devel::PPPort upgraded to version 3.03
• File::Spec upgraded to version 3.01 (as part of the new PathTools
distribution)
• Encode upgraded to version 2.08
• ExtUtils::MakeMaker remains at version 6.17, as later stable
releases currently available on CPAN have some issues with core
modules on some core platforms.
• I18N::LangTags upgraded to version 0.35
• Math::BigInt upgraded to version 1.73
• Math::BigRat upgraded to version 0.13
• MIME::Base64 upgraded to version 3.05
• POSIX::sigprocmask function can now retrieve the current signal mask
without also setting it.
• Time::HiRes upgraded to version 1.65
Utility Changes
Perl has a new -dt command-line flag, which enables threads support in
the debugger.
Performance Enhancements
"reverse sort ..." is now optimized to sort in reverse, avoiding the
generation of a temporary intermediate list.
"for (reverse @foo)" now iterates in reverse, avoiding the generation of
a temporary reversed list.
Selected Bug Fixes
The regexp engine is now more robust when given invalid utf8 input, as
is sometimes generated by buggy XS modules.
"foreach" on threads::shared array used to be able to crash Perl. This
bug has now been fixed.
A regexp in "STDOUT"'s destructor used to coredump, because the regexp
pad was already freed. This has been fixed.
"goto &" is now more robust - bugs in deep recursion and chained "goto
&" have been fixed.
Using "delete" on an array no longer leaks memory. A "pop" of an item
from a shared array reference no longer causes a leak.
eval_sv() failing a taint test could corrupt the stack - this has been
fixed.
On platforms with 64 bit pointers numeric comparison operators used to
erroneously compare the addresses of references that are overloaded,
rather than using the overloaded values. This has been fixed.
"read" into a UTF8-encoded buffer with an offset off the end of the
buffer no longer mis-calculates buffer lengths.
Although Perl has promised since version 5.8 that sort() would be
stable, the two cases "sort {$b cmp $a}" and "sort {$b <=> $a}" could
produce non-stable sorts. This is corrected in perl5.8.6.
Localising $^D no longer generates a diagnostic message about valid -D
flags.
New or Changed Diagnostics
For -t and -T,
Too late for "-T" option has been changed to the more informative
"-T" is on the #! line, it must also be used on the command line
Changed Internals
From now on all applications embedding perl will behave as if perl were
compiled with -DPERL_USE_SAFE_PUTENV. See "Environment access" in the
INSTALL file for details.
Most "C" source files now have comments at the top explaining their
purpose, which should help anyone wishing to get an overview of the
implementation.
New Tests
There are significantly more tests for the "B" suite of modules.
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://bugs.perl.org. 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. You can browse and search the Perl 5 bugs at
http://bugs.perl.org/
SEE ALSO
The Changes file for 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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