perl5154delta - what is new for perl v5.15.4
This document describes differences between the 5.15.3 release and the 5.15.4 release.
If you are upgrading from an earlier release such as 5.15.3, first read perl5153delta, which describes differences between 5.15.3 and 5.15.4.
$^X is now converted to an absolute path on OS X,
FreeBSD (without needing /proc mounted) and Solaris 10 and 11.
This augments the previous approach of using /proc on Linux,
FreeBSD and NetBSD (in all cases,
where mounted).
This makes relocatable perl installations more useful on these platforms. (See "Relocatable @INC" in INSTALL)
Perl now has proper support for Unicode in symbol names.
It used to be that *{$foo} would ignore the internal UTF8 flag and use the bytes of the underlying representation to look up the symbol.
That meant that *{"\x{100}"} and *{"\xc4\x80"} would return the same thing.
All these parts of Perl have been fixed to account for Unicode:
use overload)gotobless() and tie()ref()caller()In addition,
a parsing bug has been fixed that prevented *{é} from implicitly quoting the name,
but instead interpreted it as *{+é},
which would cause a strict violation.
*{"*a::b"} automatically strips off the * if it is followed by an ASCII letter.
That has been extended to all Unicode identifier characters.
$é is now subject to "Used only once" warnings.
It used to be exempt,
as it was treated as a punctuation variable.
Also,
single-character Unicode punctuation variables (like $‰) are now supported [perl #69032].
They are also supported with our and my,
but that is a mistake that will be fixed before 5.16.
Some parts of Perl did not work correctly with nulls (chr 0) embedded in strings.
That meant that,
for instance,
$m = "a\0b"; foo->$m would call the "a" method,
instead of the actual method name contained in $m.
These parts of perl have been fixed to support nulls:
ref()caller()*foo{"THING\0stuff"})One side effect of these changes is that blessing into "\0" no longer causes ref() to return false.
Custom sort subroutines can now be autoloaded [perl #30661]:
sub AUTOLOAD { ... }
@sorted = sort foo @list; # uses AUTOLOAD
Most XS authors will be aware that there is a longstanding bug in the OUTPUT typemap for T_AVREF (AV*), T_HVREF (HV*), T_CVREF (CV*), and T_SVREF (SVREF or \$foo) that requires manually decrementing the reference count of the return value instead of the typemap taking care of this. For backwards-compatibility, this cannot be changed in the default typemaps. But we now provide additional typemaps T_AVREF_REFCOUNT_FIXED, etc. that do not exhibit this bug. Using them in your extension is as simple as having one line in your TYPEMAP section:
HV* T_HVREF_REFCOUNT_FIXED
substr no longer calculates a value to return when called in void context.base no longer sets a module's $VERSION to "-1" when a module it loads does not define a $VERSION. This change has been made because "-1" is not a valid version number under the new "lax" criteria used internally by UNIVERSAL::VERSION. (See version for more on "lax" version criteria.)
base no longer internally skips loading modules it has already loaded and instead relies on require to inspect %INC. This fixes a bug when base is used with code that clear %INC to force a module to be reloaded.
It stopped exporting its symbols with the ExtUtils::ParseXS changes in 5.15.2. Now it exports them once more.
Resolve possible security problem [http://goo.gl/YzHRU] where a '::' prefixed module can 'jump' out of @INC
Locales updated to CLDR 2.0: ar, be, bg, ha, hr, kk, lt. Newly supported locales: as, fi__phonebook, gu, hi, kn, kok and ln.
open $fh, "<:", ... applies the default layers for the platform (:raw on Unix, :crlf on Windows), ignoring whatever is declared by open.pm. This seems such a useful feature it has been documented in perlfunc and open.boolSV() macro is now documented.The following additions or changes have been made to diagnostic output, including warnings and fatal error messages. For the complete list of diagnostic messages, see perldiag.
HvNAMELEN
HvNAMEUTF8
HvENAMELEN
HvENAMEUTF8
gv_init_pv
gv_init_pvn
gv_init_pvsv
gv_fetchmeth_pv
gv_fetchmeth_pvn
gv_fetchmeth_sv
gv_fetchmeth_pv_autoload
gv_fetchmeth_pvn_autoload
gv_fetchmeth_sv_autoload
gv_fetchmethod_pv_flags
gv_fetchmethod_pvn_flags
gv_fetchmethod_sv_flags
gv_autoload_pv
gv_autoload_pvn
gv_autoload_sv
newGVgen_flags
sv_derived_from_pv
sv_derived_from_pvn
sv_derived_from_sv
sv_does_pv
sv_does_pvn
sv_does_sv
whichsig_pv
whichsig_pvn
whichsig_sv
newCONSTSUB_flags
The gv_fetchmethod_*_flags functions, like gv_fetchmethod_flags, are experimental and may change in a future release.
GvNAMEUTF8
GvENAMELEN
GvENAME_HEK
CopSTASH_flags
CopSTASH_flags_set
PmopSTASH_flags
PmopSTASH_flags_set
sv_sethek
HEKfARG
There is also a HEKf macro corresponding to SVf, for interpolating HEKs in formatted strings.
sv_catpvn_flags takes a couple of new internal-only flags, SV_CATBYTES and SV_CATUTF8, which tell it whether the char array to be concatenated is UTF8. This allows for more efficient concatenation than creating temporary SVs to pass to sv_catsv.SvPVX(cv), for compatibility with 5.8 to 5.14. See "Autoloading with XSUBs" in perlguts.mro::get_linear_isa may return an array with one more element than the MRO plugin provided [perl #94306].$tainted ~~ @array stopped working properly. Sometimes it would erroneously fail (when $tainted contained a string that occurs in the array after the first element) or erroneously succeed (when undef occurred after the first element) [perl #93590]."foo"->CORE::ucfirst returns Foo.use and require are no longer affected by the I/O layers active in the caller's scope (enabled by open.pm) [perl #96008].%overload:: no longer causes a crash.our $::é; $é (which is invalid) no longer produces the "Compilation error at lib/utf8_heavy.pl..." error message, which it started emitting in 5.10.0 [perl #99984].\p{...}) matched non-Unicode code points."f\x{FB00}" =~ /ff/i to fail.read() now understands large string offsets beyond the 32-bit range.sort now works once more with custom sort routines that are XSUBs. It stopped working in 5.10.0.sort with a constant for a custom sort routine, although it produces unsorted results, no longer crashes. It started crashing in 5.10.0.sort { $a <=> $b }, which is optimised internally, now produces "uninitialized" warnings for NaNs (not-a-number values), since <=> returns undef for those. This brings it in line with sort { 1; $a <=> $b } and other more complex cases, which are not optimised [perl #94390]... and ... in list context now call FETCH only once on tied arguments, instead of three or four times [perl #53554]... and ... in list context now mention the name of the variable in "uninitialized" warnings for string (as opposed to numeric) ranges.Perl 5.15.4 represents approximately 1 month of development since Perl 5.15.3 and contains approximately 31,000 lines of changes across 350 files from 23 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 5.15.4:
Alan Haggai Alavi, Brian Fraser, Chip Salzenberg, Chris 'BinGOs' Williams, Dave Rolsky, David Golden, David Mitchell, Dennis Kaarsemaker, Eric Brine, Father Chrysostomos, Florian Ragwitz, George Greer, Gerard Goossen, H.Merijn Brand, Jim Cromie, John P. Linderman, Karl Williamson, Nicholas Clark, Reini Urban, Steffen Müller, Stevan Little, Thorsten Glaser, 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.
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.
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.
