Back to main site | Back to man page index

PERL583DELTA(1)                            Perl Programmers Reference Guide                           PERL583DELTA(1)



NAME
       perl583delta - what is new for perl v5.8.3

DESCRIPTION
       This document describes differences between the 5.8.2 release and the 5.8.3 release.

       If you are upgrading from an earlier release such as 5.6.1, first read the perl58delta, which describes
       differences between 5.6.0 and 5.8.0, and the perl581delta and perl582delta, which describe differences between
       5.8.0, 5.8.1 and 5.8.2

Incompatible Changes
       There are no changes incompatible with 5.8.2.

Core Enhancements
       A "SCALAR" method is now available for tied hashes. This is called when a tied hash is used in scalar context,
       such as

           if (%tied_hash) {
               ...
           }

       The old behaviour was that %tied_hash would return whatever would have been returned for that hash before the
       hash was tied (so usually 0). The new behaviour in the absence of a SCALAR method is to return TRUE if in the
       middle of an "each" iteration, and otherwise call FIRSTKEY to check if the hash is empty (making sure that a
       subsequent "each" will also begin by calling FIRSTKEY). Please see "SCALAR" in perltie for the full details
       and caveats.

Modules and Pragmata
       CGI
       Cwd
       Digest
       Digest::MD5
       Encode
       File::Spec
       FindBin
           A function "again" is provided to resolve problems where modules in different directories wish to use
           FindBin.

       List::Util
           You can now weaken references to read only values.

       Math::BigInt
       PodParser
       Pod::Perldoc
       POSIX
       Unicode::Collate
       Unicode::Normalize
       Test::Harness
       threads::shared
           "cond_wait" has a new two argument form. "cond_timedwait" has been added.

Utility Changes
       "find2perl" now assumes "-print" as a default action. Previously, it needed to be specified explicitly.

       A new utility, "prove", makes it easy to run an individual regression test at the command line. "prove" is
       part of Test::Harness, which users of earlier Perl versions can install from CPAN.

       join() could return garbage when the same join() statement was used to process 8 bit data having earlier
       processed UTF8 data, due to the flags on that statement's temporary workspace not being reset correctly. This
       is now fixed.

       "$a .. $b" will now work as expected when either $a or $b is "undef"

       Using Unicode keys with tied hashes should now work correctly.

       Reading $^E now preserves $!. Previously, the C code implementing $^E did not preserve "errno", so reading $^E
       could cause "errno" and therefore $! to change unexpectedly.

       Reentrant functions will (once more) work with C++. 5.8.2 introduced a bugfix which accidentally broke the
       compilation of Perl extensions written in C++

New or Changed Diagnostics
       The fatal error "DESTROY created new reference to dead object" is now documented in perldiag.

Changed Internals
       The hash code has been refactored to reduce source duplication. The external interface is unchanged, and aside
       from the bug fixes described above, there should be no change in behaviour.

       "hv_clear_placeholders" is now part of the perl API

       Some C macros have been tidied. In particular macros which create temporary local variables now name these
       variables more defensively, which should avoid bugs where names clash.

       <signal.h> is now always included.

Configuration and Building
       "Configure" now invokes callbacks regardless of the value of the variable they are called for. Previously
       callbacks were only invoked in the "case $variable $define)" branch. This change should only affect platform
       maintainers writing configuration hints files.

Platform Specific Problems
       The regression test ext/threads/shared/t/wait.t fails on early RedHat 9 and HP-UX 10.20 due to bugs in their
       threading implementations.  RedHat users should see https://rhn.redhat.com/errata/RHBA-2003-136.html and
       consider upgrading their glibc.

Known Problems
       Detached threads aren't supported on Windows yet, as they may lead to memory access violation problems.

       There is a known race condition opening scripts in "suidperl". "suidperl" is neither built nor installed by
       default, and has been deprecated since perl 5.8.0. You are advised to replace use of suidperl with tools such
       as sudo ( http://www.courtesan.com/sudo/ )

       We have a backlog of unresolved bugs. Dealing with bugs and bug reports is unglamorous work; not something
       ideally suited to volunteer labour, but that is all that we have.

       The perl5 development team are implementing changes to help address this problem, which should go live in
       early 2004.

Future Directions
       Code freeze for the next maintenance release (5.8.4) is on March 31st 2004, with release expected by mid
       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 [email protected] 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.



perl v5.16.3                                          2013-02-26                                      PERL583DELTA(1)