NAME¶
perl5132delta - what is new for perl v5.13.2
DESCRIPTION¶
This document describes differences between the 5.13.2 release and the 5.13.1
release.
If you are upgrading from an earlier release such as 5.10, first read
perl5120delta, which describes differences between 5.10 and 5.12.
Incompatible Changes¶
localised tied scalars are tied again.¶
The change in behaviour in 5.13.1 of localising tied scalar values has been
reverted to the existing 5.12.0 and earlier behaviour (the change for arrays
and hashes remains).
Naming fixes in Policy_sh.SH may invalidate Policy.sh¶
Several long-standing typos and naming confusions in Policy_sh.SH have been
fixed, standardizing on the variable names used in config.sh.
This will change the behavior of Policy.sh if you happen to have been
accidentally relying on the Policy.sh incorrect behavior. We'd appreciate
feedback from anyone using Policy.sh to be sure nothing is broken by this
change (c1bd23).
Stashes are now always defined¶
"defined %Foo::" now always returns true, even when no symbols have
yet been defined in that package.
This is a side effect of removing a special case kludge in the tokeniser, added
for 5.10.0, to hide side effects of changes to the internal storage of hashes
that to drastically reduce their memory usage overhead.
Calling defined on a stash has been deprecated since 5.6.0, warned on lexicals
since 5.6.0, and has warned for stashes (and other package variables) since
5.12.0. "defined %hash" has always exposed an implementation detail
- emptying a hash by deleting all entries from it does not make "defined
%hash" false, hence "defined %hash" is not valid code to
determine whether an arbitrary hash is empty. Instead, use the behaviour that
an empty %hash always returns false in a scalar context.
Core Enhancements¶
Non-destructive substitution¶
The substitution operator now supports a "/r" option that copies the
input variable, carries out the substitution on the copy and returns the
result. The original remains unmodified.
my $old = 'cat';
my $new = $old =~ s/cat/dog/r;
# $old is 'cat' and $new is 'dog'
This is particularly useful with "map". See perlop for more examples
(4f4d75, 000c65).
package block syntax¶
A package declaration can now contain a code block, in which case the
declaration is in scope only inside that block. So "package Foo { ...
}" is precisely equivalent to "{ package Foo; ... }". It also
works with a version number in the declaration, as in "package Foo 1.2 {
... }". See perlfunc (434da3..36f77d, 702646).
CLONE_PARAMS structure added to ease correct thread creation¶
Modules that create threads should now create "CLONE_PARAMS"
structures by calling the new function "Perl_clone_params_new()",
and free them with "Perl_clone_params_del()". This will ensure
compatibility with any future changes to the internals of the
"CLONE_PARAMS" structure layout, and that it is correctly allocated
and initialised.
perl -h no longer recommends -w¶
perl -h used to mark the -w option as recommended; since this option is far less
useful than it used to be due to lexical 'use warnings' and since perl -h is
primary a list and brief explanation of the command line switches, the
recommendation has now been removed (60eaec).
Modules and Pragmata¶
Updated Modules¶
Locale-Codes 3.13
Locale::Country, Locale::Language and Locale::Currency were updated from 3.12 to
3.13 of the Locale-Codes distribution to include locale code changes (e1137b).
Thread-Semaphore 2.11
Added new methods ->
down_nb() and ->
down_force() at the
suggestion of Rick Garlick.
Refactored methods to skip argument validation when no argument is supplied.
(04febe, f06daa)
CPAN.pm 1.94_57
- •
- release 1.94_57
- •
- bugfix: treat modules correctly that are deprecated in perl
5.12.
- •
- bugfix: RT #57482 and #57788 revealed that
configure_requires implicitly assumed build_requires instead of normal
requires. (Reported by Andrew Whatson and Father Chrysostomos
respectively)
- •
- testfix: solaris should run the tests without expect
because (some?) solaris have a broken expect
- •
- testfix: run tests with cache_metadata off to prevent spill
over effects from previous test runs
(742adb)
Hash::Util warning fix
Hash::Util now enables "no warnings 'uninitialized'" to suppress
spurious warnings from undefined hash values (RT #74280).
B::Deparse now handles 'no VERSION'
The 'no 5.13.2' or similar form is now correctly handled by B::Deparse.
IO::Socket doc additions
getsockopt and setsockopt are now documented.
B::Concise updated for OPpDEREF
B::Concise marks rv2sv, rv2av and rv2hv ops with the new OPpDEREF flag as
"DREFed".
File::Copy doc clarification
An extra stanza was added explaining behaviours when the copy destination
already exists and is a directory.
Multiple POD spelling fixes.
Fixes were made to VMS::DCLsym, mro, Search::Dist, B::t::OptreeCheck and
UNIVERSAL.
Changes to Existing Documentation¶
Replace wrong tr/// table in perlebcdic.pod¶
perlebcdic.pod contains a helpful table to use in tr/// to convert between
EBCDIC and Latin1/ASCII. Unfortunately, the table was the inverse of the one
it describes, though the code that used the table worked correctly for the
specific example given.
The table has been changed to its inverse, and the sample code changed to
correspond, as this is easier for the person trying to follow the instructions
since deriving the old table is somewhat more complicated.
The table has also been changed to hex from octal, as that is more the norm
these days, and the recipes in the pod altered to print out leading zeros to
make all the values the same length, as the table that they can generate has
them (5f26d5).
Document tricks for user-defined casing¶
perlunicode.pod now contains an explanation of how to override, mangle and
otherwise tweak the way perl handles upper, lower and other case conversions
on unicode data, and how to provide scoped changes to alter one's own code's
behaviour without stomping on anybody else (71648f).
Document $# and $* as removed and clarify $#array usage¶
$# and $* were both disabled as of perl5 version 10; this release adds
documentation to that effect, a description of the results of continuing to
try and use them, and a note explaining that $# can also function as a sigil
in the $#array form (7f315d2).
INSTALL explicitly states the requirement for C89¶
This was already true but it's now Officially Stated For The Record (51eec7).
No longer advertise Math::TrulyRandom¶
This module hasn't been updated since 1996 so we can't recommend it any more
(83918a).
perlfaq synchronised to upstream¶
The FAQ has been updated to commit 37550b8f812e591bcd0dd869d61677dac5bda92c from
the perlfaq repository at git@github.com:briandfoy/perlfaq.git
Only allocate entries for @_ on demand - this not only saves memory per
subroutine defined but should hopefully improve COW behaviour (77bac2).
Multiple small improvements to threads¶
The internal structures of threading now make fewer API calls and fewer
allocations, resulting in noticeably smaller object code. Additionally, many
thread context checks have been deferred so that they're only done when
required (although this is only possible for non-debugging builds).
Size optimisations to SV and HV structures¶
xhv_fill has been eliminated from struct xpvhv, saving 1 IV per hash and on some
systems will cause struct xpvhv to become cache aligned. To avoid this memory
saving causing a slowdown elsewhere, boolean use of HvFILL now calls
HvTOTALKEYS instead (which is equivalent) - so while the fill data when
actually required is now calculated on demand, the cases when this needs to be
done should be few and far between (f4431c .. fcd245).
The order of structure elements in SV bodies has changed. Effectively, the NV
slot has swapped location with STASH and MAGIC. As all access to SV members is
via macros, this should be completely transparent. This change allows the
space saving for PVHVs documented above, and may reduce the memory allocation
needed for PVIVs on some architectures.
Optimisation of regexp engine string comparison work¶
The foldEQ_utf8 API function for case-insensitive comparison of strings (which
is used heavily by the regexp engine) was substantially refactored and
optimised - and its documentation much improved as a free bonus gift (8b3587,
e6226b).
Memory consumption improvements to Exporter¶
The @EXPORT_FAIL AV is no longer created unless required, hence neither is the
typeglob backing it - this saves about 200 bytes per Exporter using package
that doesn't use this functionality.
Installation and Configuration Improvements¶
Compilation improvements¶
Fix CCINCDIR and CCLIBDIR for mingw64 cross compiler to correctly be under
$(CCHOME)\mingw\include and \lib rather than immediately below $(CCHOME).
This means the 'incpath', 'libpth', 'ldflags', 'lddlflags' and
'ldflags_nolargefiles' values in Config.pm and Config_heavy.pl are now set
correctly (23ae7f).
Selected Bug Fixes¶
- •
- Timely cleanup of SVs that are cloned into a new thread but
then discovered to be orphaned (i.e. their owners are -not- cloned)
(e42956)
- •
- Don't accidentally clone lexicals in scope within active
stack frames in the parent when creating a child thread (RT #73086)
(05d04d).
- •
- Avoid loading feature.pm when 'no 5.13.2;' or similar is
encountered (faee19).
- •
- Trap invalid use of SvIVX on SVt_REGEXP when assertions are
on (e77da3)
- •
- Don't stamp on $DB::single, $DB::trace and $DB::signal if
they already have values when $^P is assigned to (RT #72422)
(4c0f30).
- •
- chop now correctly handles perl's extended UTF-8 (RT
#73246) (65ab92)
- •
- Defer signal handling when shared SV locks are held to
avoid deadlocks (RT #74868) (65c742).
- •
- glob() no longer crashes when %File::Glob:: is empty
and CORE::GLOBAL::glob isn't present (4984aa).
- •
- perlbug now always permits the sender address to be changed
before sending - if you were having trouble sending bug reports before
now, this should fix it, we hope (e6eb90).
- •
- Overloading now works properly in conjunction with tied
variables. What formerly happened was that most ops checked their
arguments for overloading before checking for magic, so for example
an overloaded object returned by a tied array access would usually be
treated as not overloaded (RT #57012) (6f1401, ed3b9b, 6a5f8c ..
24328f).
- •
- Independently, a bug was fixed that prevented $tied->()
from always calling FETCH correctly (RT #8438) (7c7501)
Changed Internals¶
- •
- The implementation of sv_dup_inc() has changed from
a macro to a function.
- •
- The "find_rundefsvoffset" function has been
deprecated. It appeared that its design was insufficient to reliably get
the lexical $_ at run-time.
Use the new "find_rundefsv" function or the "UNDERBAR"
macro instead. They directly return the right SV representing $_, whether
it's lexical or dynamic (789bd8 .. 03d5bc).
- •
- The following new functions or macros have been added to
the public API: "SvNV_nomg", "sv_2nv_flags",
"find_rundefsv".
- •
- The "UNDERBAR" macro now calls
"find_rundefsv". "dUNDERBAR" is now a noop but should
still be used to ensure past and future compatibility.
- •
- The ibcmp_* functions have been renamed and are now called
foldEQ, foldEQ_locale and foldEQ_utf8 (e6226b).
Deprecations¶
The following items are now deprecated.
- •
- Omitting a space between a regex pattern or pattern
modifiers and the following word is deprecated. For example,
"m/foo/sand $bar" will still be parsed as "m/foo/s and
$bar" but will issue a warning.
Recent OpenBSDs now use perl's malloc¶
OpenBSD > 3.7 has a new malloc implementation which is mmap based and as such
can release memory back to the OS; however for perl using this malloc causes a
substantial slowdown so we now default to using perl's malloc instead (RT
#75742) (9b58b5).
Acknowledgements¶
Perl 5.13.2 represents thirty days of development since Perl 5.13.1 (and two
days of waiting around while the release manager remembered where he left his
brain) and contains 3685 lines of changes across 194 files from 30 authors and
committers.
Thank you to the following for contributing to this release:
Abigail, Andreas J. Koenig, Chas. Owens, Chris 'BinGOs' Williams, Craig A.
Berry, David Caldwell, David Golden, David Mitchell, Father Chrysostomos,
George Greer, H.Merijn Brand, Jerry D. Hedden, Karl Williamson, Maik Hentsche,
Matt S Trout, Nicholas Clark, Rafael Garcia-Suarez, Ricardo Signes, Salvador
Fandino, Salvador Ortiz Garcia, Shlomi Fish, Sinan Unur, Sisyphus, Slaven
Rezic, Sullivan Beck, Tony Cook, Vincent Pit, Zefram, brian d foy, AEvar
Arnfjoerd` Bjarmason
Your humble release manager would like to specifically call out Karl Williamson
for making the tests a better place to be, and Shlomi Fish for a passel of
tiny incremental docfixes of the sort that don't get made often enough.
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 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.