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NAME

perl5254delta - what is new for perl v5.25.4

DESCRIPTION

This document describes differences between the 5.25.3 release and the 5.25.4 release.

If you are upgrading from an earlier release such as 5.25.2, first read perl5253delta, which describes differences between 5.25.2 and 5.25.3.

Performance Enhancements

  • The rather slow implementation for the experimental subroutine signatures feature has been made much faster; it is now comparable in speed with the old-style my ($a, $b, @c) = @_.

Documentation

Changes to Existing Documentation

perlcall

  • Removed redundant dSP from an example.

Modules and Pragmata

Updated Modules and Pragmata

  • Archive::Tar has been upgraded from version 2.08 to 2.10.

  • arybase has been upgraded from version 0.11 to 0.12.

  • B has been upgraded from version 1.62 to 1.63.

  • B::Concise has been upgraded from version 0.996 to 0.998.

  • B::Deparse has been upgraded from version 1.37 to 1.38.

  • base has been upgraded from version 2.23 to 2.24.

  • bignum has been upgraded from version 0.43 to 0.43_01.

  • Carp has been upgraded from version 1.41 to 1.42.

  • Config::Perl::V has been upgraded from version 0.26 to 0.27.

  • CPAN has been upgraded from version 2.14 to 2.14_01.

  • CPAN::Meta has been upgraded from version 2.150005 to 2.150010.

  • Digest has been upgraded from version 1.17 to 1.17_01.

  • Digest::SHA has been upgraded from version 5.95 to 5.96.

  • Encode has been upgraded from version 2.84 to 2.86.

  • encoding has been upgraded from version 2.17_01 to 2.18.

  • Errno has been upgraded from version 1.25 to 1.26.

  • ExtUtils::MakeMaker has been upgraded from version 7.18 to 7.24.

  • File::Fetch has been upgraded from version 0.48 to 0.52.

  • File::Spec has been upgraded from version 3.64 to 3.65.

  • Hash::Util has been upgraded from version 0.20 to 0.21.

  • HTTP::Tiny has been upgraded from version 0.058 to 0.064.

  • I18N::LangTags has been upgraded from version 0.40 to 0.41.

  • IO has been upgraded from version 1.36 to 1.37.

  • IO-Compress has been upgraded from version 2.069 to 2.069_01.

  • IO::Socket::IP has been upgraded from version 0.37 to 0.38.

  • IPC::Cmd has been upgraded from version 0.94 to 0.96.

  • JSON::PP has been upgraded from version 2.27400 to 2.27400_01.

  • Locale::Maketext has been upgraded from version 1.27 to 1.28.

  • Locale::Maketext::Simple has been upgraded from version 0.21 to 0.21_01.

  • Memoize has been upgraded from version 1.03 to 1.03_01.

  • Module::CoreList has been upgraded from version 5.20160720 to 5.20160820.

  • Module::Load::Conditional has been upgraded from version 0.64 to 0.68.

  • Module::Metadata has been upgraded from version 1.000032 to 1.000033.

  • Net::Ping has been upgraded from version 2.43 to 2.44.

  • NEXT has been upgraded from version 0.65 to 0.67.

  • Opcode has been upgraded from version 1.35 to 1.37.

  • Pod::Html has been upgraded from version 1.22 to 1.2201.

  • Pod::Perldoc has been upgraded from version 3.25_02 to 3.27.

  • POSIX has been upgraded from version 1.70 to 1.71.

  • Storable has been upgraded from version 2.56 to 2.57.

  • Sys::Syslog has been upgraded from version 0.34 to 0.34_01.

  • Test has been upgraded from version 1.28 to 1.29.

  • Test::Harness has been upgraded from version 3.36 to 3.36_01.

  • Test::Simple has been upgraded from version 1.302045 to 1.302052.

  • Tie::Hash::NamedCapture has been upgraded from version 0.09 to 0.10.

  • Time::Local has been upgraded from version 1.2300 to 1.24.

Configuration and Compilation

  • A probe for gai_strerror was added to Configure that checks if the the gai_strerror() routine is available and can be used to translate error codes returned by getaddrinfo() into human readable strings.

Platform Support

Platform-Specific Notes

Hurd

The hints for Hurd have been improved enabling malloc wrap and reporting the GNU libc used (previously it was an empty string when reported).

Internal Changes

  • Three new ops, OP_ARGELEM, OP_ARGDEFELEM and OP_ARGCHECK have been added. These are intended principally to implement the individual elements of a subroutine signature, plus any overall checking required.

Selected Bug Fixes

  • Problems with in-place array sorts: code like @a = sort { ... } @a, where the source and destination of the sort are the same plain array, are optimised to do less copying around. Two side-effects of this optimisation were that the contents of @a as visible to to sort routine were partially sorted, and under some circumstances accessing @a during the sort could crash the interpreter. Both these issues have been fixed, and Sort functions see the original value of @a.

  • Non-ASCII string delimiters are now reported correctly in error messages for unterminated strings. [perl #128701]

  • pack("p", ...) used to emit its warning ("Attempt to pack pointer to temporary value") erroneously in some cases, but has been fixed.

  • @DB::args is now exempt from "used once" warnings. The warnings only occurred under -w, because warnings.pm itself uses @DB::args multiple times.

  • The use of built-in arrays or hash slices in a double-quoted string no longer issues a warning ("Possible unintended interpolation...") if the variable has not been mentioned before. This affected code like qq|@DB::args| and qq|@SIG{'CHLD', 'HUP'}|. (The special variables @- and @+ were already exempt from the warning.)

  • gethostent and similar functions now perform a null check internally, to avoid crashing with torsocks. This was a regression from 5.22. [perl #128740]

  • defined *{'!'}, defined *{'['}, and defined *{'-'} no longer leak memory if the typeglob in question has never been accessed before.

  • In 5.25.4 fchown() was changed not to accept negative one as an argument because in some platforms that is an error. However, in some other platforms that is an acceptable argument. This change has been reverted [perl #128967].

  • Mentioning the same constant twice in a row (which is a syntax error) no longer fails an assertion under debugging builds. This was a regression from 5.20. [perl #126482]

  • Many issues relating to printf "%a" of hexadecimal floating point were fixed. In addition, the "subnormals" (formerly known as "denormals") floating point anumbers are now supported both with the plain IEEE 754 floating point numbers (64-bit or 128-bit) and the x86 80-bit "extended precision". Note that subnormal hexadecimal floating point literals will give a warning about "exponent underflow". [perl #128843, #128889, #128890, #128893, #128909, #128919]

  • A regression in 5.24 with tr/\N{U+...}/foo/ when the code point was between 128 and 255 has been fixed. [perl #128734].

  • A regression from the previous development release, 5.23.3, where compiling a regular expression could crash the interpreter has been fixed. [perl #128686].

  • Use of a string delimiter whose code point is above 2**31 now works correctly on platforms that allow this. Previously, certain characters, due to truncation, would be confused with other delimiter characters with special meaning (such as ? in m?...?), resulting in inconsistent behaviour. Note that this is non-portable, and is based on Perl's extension to UTF-8, and is probably not displayable nor enterable by any editor. [perl #128738]

  • @{x followed by a newline where x represents a control or non-ASCII character no longer produces a garbled syntax error message or a crash. [perl #128951]

Acknowledgements

Perl 5.25.4 represents approximately 4 weeks of development since Perl 5.25.3 and contains approximately 18,000 lines of changes across 820 files from 23 authors.

Excluding auto-generated files, documentation and release tools, there were approximately 9,200 lines of changes to 660 .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 5.25.4:

Chris 'BinGOs' Williams, Craig A. Berry, Dagfinn Ilmari Mannsåker, Dan Collins, Daniel Dragan, David Mitchell, Father Chrysostomos, H.Merijn Brand, James E Keenan, Jarkko Hietaniemi, Karen Etheridge, Karl Williamson, Lukas Mai, Neil Bowers, Nicolas R., Pino Toscano, Rafael Garcia-Suarez, Richard Levitte, Shlomi Fish, Smylers, Steve Hay, Tony Cook, Yves Orton.

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 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 see "SECURITY VULNERABILITY CONTACT INFORMATION" in perlsec for details of how to report the issue.

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.