PERL5221DELTA(1) Perl Programmers Reference Guide PERL5221DELTA(1)
NAME
perl5221delta - what is new for perl v5.22.1
DESCRIPTION
This document describes differences between the 5.22.0 release and the
5.22.1 release.
If you are upgrading from an earlier release such as 5.20.0, first read
perl5220delta, which describes differences between 5.20.0 and 5.22.0.
Incompatible Changes
There are no changes intentionally incompatible with 5.20.0 other than
the following single exception, which we deemed to be a sensible change
to make in order to get the new "\b{wb}" and (in particular) "\b{sb}"
features sane before people decided they're worthless because of bugs in
their Perl 5.22.0 implementation and avoided them in the future. If any
others exist, they are bugs, and we request that you submit a report.
See "Reporting Bugs" below.
Bounds Checking Constructs
Several bugs, including a segmentation fault, have been fixed with the
bounds checking constructs (introduced in Perl 5.22) "\b{gcb}",
"\b{sb}", "\b{wb}", "\B{gcb}", "\B{sb}", and "\B{wb}". All the "\B{}"
ones now match an empty string; none of the "\b{}" ones do. [GH #14976]
<https://github.com/Perl/perl5/issues/14976>
Modules and Pragmata
Updated Modules and Pragmata
• Module::CoreList has been upgraded from version 5.20150520 to
5.20151213.
• PerlIO::scalar has been upgraded from version 0.22 to 0.23.
• POSIX has been upgraded from version 1.53 to 1.53_01.
If "POSIX::strerror" was passed $! as its argument then it
accidentally cleared $!. This has been fixed. [GH #14951]
<https://github.com/Perl/perl5/issues/14951>
• Storable has been upgraded from version 2.53 to 2.53_01.
• warnings has been upgraded from version 1.32 to 1.34.
The "warnings::enabled" example now actually uses
"warnings::enabled". [GH #14905]
<https://github.com/Perl/perl5/issues/14905>
• Win32 has been upgraded from version 0.51 to 0.52.
This has been updated for Windows 8.1, 10 and 2012 R2 Server.
Documentation
Changes to Existing Documentation
perltie
• The usage of "FIRSTKEY" and "NEXTKEY" has been clarified.
perlvar
• The specific true value of $!{E...} is now documented, noting that
it is subject to change and not guaranteed.
Diagnostics
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.
Changes to Existing Diagnostics
• The "printf" and "sprintf" builtins are now more careful about the
warnings they emit: argument reordering now disables the "redundant
argument" warning in all cases. [GH #14772]
<https://github.com/Perl/perl5/issues/14772>
Configuration and Compilation
• Using the "NO_HASH_SEED" define in combination with the default hash
algorithm "PERL_HASH_FUNC_ONE_AT_A_TIME_HARD" resulted in a fatal
error while compiling the interpreter, since Perl 5.17.10. This has
been fixed.
• Configuring with ccflags containing quotes (e.g.
"-Accflags='-DAPPLLIB_EXP=\"/usr/libperl\"'") was broken in Perl
5.22.0 but has now been fixed again. [GH #14732]
<https://github.com/Perl/perl5/issues/14732>
Platform Support
Platform-Specific Notes
IRIX
• Under some circumstances IRIX stdio fgetc() and fread() set the
errno to "ENOENT", which made no sense according to either IRIX
or POSIX docs. Errno is now cleared in such cases. [GH #14557]
<https://github.com/Perl/perl5/issues/14557>
• Problems when multiplying long doubles by infinity have been
fixed. [GH #14993] <https://github.com/Perl/perl5/issues/14993>
• All tests pass now on IRIX with the default build configuration.
Selected Bug Fixes
• "qr/(?[ () ])/" no longer segfaults, giving a syntax error message
instead. [GH #14851] <https://github.com/Perl/perl5/issues/14851>
• Regular expression possessive quantifier Perl 5.20 regression now
fixed. "qr/"PAT"{"min,max"}+""/" is supposed to behave identically
to "qr/(?>"PAT"{"min,max"})/". Since Perl 5.20, this didn't work if
min and max were equal. [GH #14857]
<https://github.com/Perl/perl5/issues/14857>
• Certain syntax errors in "Extended Bracketed Character Classes" in
perlrecharclass caused panics instead of the proper error message.
This has now been fixed. [GH #15016]
<https://github.com/Perl/perl5/issues/15016>
• "BEGIN <>" no longer segfaults and properly produces an error
message. [GH #13546] <https://github.com/Perl/perl5/issues/13546>
• A regression from Perl 5.20 has been fixed, in which some syntax
errors in "(?[...])" constructs within regular expression patterns
could cause a segfault instead of a proper error message. [GH
#14933] <https://github.com/Perl/perl5/issues/14933>
• Another problem with "(?[...])" constructs has been fixed wherein
things like "\c]" could cause panics. [GH #14934]
<https://github.com/Perl/perl5/issues/14934>
• In Perl 5.22.0, the logic changed when parsing a numeric parameter
to the -C option, such that the successfully parsed number was not
saved as the option value if it parsed to the end of the argument.
[GH #14748] <https://github.com/Perl/perl5/issues/14748>
• Warning fatality is now ignored when rewinding the stack. This
prevents infinite recursion when the now fatal error also causes
rewinding of the stack. [GH #14319]
<https://github.com/Perl/perl5/issues/14319>
• A crash with "%::=(); J->${\"::"}" has been fixed. [GH #14790]
<https://github.com/Perl/perl5/issues/14790>
• Nested quantifiers such as "/.{1}??/" should cause perl to throw a
fatal error, but were being silently accepted since Perl 5.20.0.
This has been fixed. [GH #14960]
<https://github.com/Perl/perl5/issues/14960>
• Regular expression sequences such as "/(?i/" (and similarly with
other recognized flags or combination of flags) should cause perl to
throw a fatal error, but were being silently accepted since Perl
5.18.0. This has been fixed. [GH #14931]
<https://github.com/Perl/perl5/issues/14931>
• A bug in hexadecimal floating point literal support meant that high-
order bits could be lost in cases where mantissa overflow was caused
by too many trailing zeros in the fractional part. This has been
fixed. [GH #15032] <https://github.com/Perl/perl5/issues/15032>
• Another hexadecimal floating point bug, causing low-order bits to be
lost in cases where the last hexadecimal digit of the mantissa has
bits straddling the limit of the number of bits allowed for the
mantissa, has also been fixed. [GH #15033]
<https://github.com/Perl/perl5/issues/15033>
• Further hexadecimal floating point bugs have been fixed: In some
circumstances, the %a format specifier could variously lose the sign
of the negative zero, fail to display zeros after the radix point
with the requested precision, or even lose the radix point after the
leftmost hexadecimal digit completely.
• A crash caused by incomplete expressions within "/(?[ ])/" (e.g.
"/(?[[0]+()+])/") has been fixed. [GH #15045]
<https://github.com/Perl/perl5/issues/15045>
Acknowledgements
Perl 5.22.1 represents approximately 6 months of development since Perl
5.22.0 and contains approximately 19,000 lines of changes across 130
files from 27 authors.
Excluding auto-generated files, documentation and release tools, there
were approximately 1,700 lines of changes to 44 .pm, .t, .c and .h
files.
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 5.22.1:
Aaron Crane, Abigail, Andy Broad, Aristotle Pagaltzis, Chase Whitener,
Chris 'BinGOs' Williams, Craig A. Berry, Daniel Dragan, David Mitchell,
Father Chrysostomos, Herbert Breunung, Hugo van der Sanden, James E
Keenan, Jan Dubois, Jarkko Hietaniemi, Karen Etheridge, Karl Williamson,
Lukas Mai, Matthew Horsfall, Peter Martini, Rafael Garcia-Suarez,
Ricardo Signes, Shlomi Fish, Sisyphus, Steve Hay, Tony Cook, Victor
Adam.
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 https://rt.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.
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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