perl5296delta - what is new for perl v5.29.6
This document describes differences between the 5.29.5 release and the 5.29.6 release.
If you are upgrading from an earlier release such as 5.29.4, first read perl5295delta, which describes differences between 5.29.4 and 5.29.5.
A crafted regular expression could cause heap-buffer-overflow write during compilation, potentially allowing arbitrary code execution. (This was actually fixed in 5.29.4, but not announced as a security fix at the time). [perl #133423]
Optimization of IV to UV conversions. [perl #133677].
IV
UV
Speed up of the integer stringification algorithm by processing two digits at a time instead of one. [perl #133691].
Improvements based on LGTM analysis and recommendation. (https://lgtm.com/projects/g/Perl/perl5/alerts/?mode=tree). [perl #133686]. [perl #133699].
Code optimizations in regcomp.c, regcomp.h, regexec.c.
Config::Perl::V. has been upgraded from version 0.30 to 0.32. This was due to a new configuration variable that has influence on binary compatibility: USE_THREAD_SAFE_LOCALE.
USE_THREAD_SAFE_LOCALE
ExtUtils::ParseXS has been upgraded from version 3.39 to 3.40. OUTLIST parameters are no longer incorrectly included in the automatically generated function prototype. [perl #133654].
OUTLIST
File::Find has been upgraded from version 1.34 to 1.35. $File::Find::dont_use_nlink now defaults to 1 on all platforms. [perl #133673].
$File::Find::dont_use_nlink
Module::CoreList has been upgraded from version 5.20181120 to 5.20181218.
POSIX has been upgraded from version 1.85 to 1.86.
Storable has been upgraded from version 3.13 to 3.14.
Storable no longer probes for recursion limits at build time. [perl #133708] and others.
Metasploit exploit code was included to test for CVE-2015-1992 detection, this caused anti-virus detections on at least one AV suite. The exploit code has been removed and replaced with a simple functional test. [perl #133706]
Test::Simple has been upgraded from version 1.302140 to 1.302141.
threads::shared has been upgraded from version 1.58 to 1.59.
We have attempted to update the documentation to reflect the changes listed in this document. If you find any we have missed, send email to perlbug@perl.org.
Additionally, the following selected changes have been made:
Clarification of behaviour of reset EXPR.
reset EXPR
Clarification of the syntax of /(?(cond)yes)/.
We no longer have null (empty line) here doc terminators, so perlop should not refer to them.
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.
Under -Dr (or use re 'Debug') the compiled regex engine program is displayed. It used two different spellings for infinity, INFINITY, and INFTY. It now uses the latter exclusively, as that spelling has been around the longest.
-Dr
use re 'Debug'
INFINITY
INFTY
The generated prototype (with PROTOTYPES: ENABLE) would include OUTLIST parameters, but these aren't arguments to the perl function. This has been rectified. [perl #133654].
PROTOTYPES: ENABLE
Tests were added and changed to reflect the other additions and changes in this release. Furthermore, these significant changes were made:
Some tests in t/io/eintr.t caused the process to hang on pre-16 Darwin. These tests are skipped for those version of Darwin.
Cygwin doesn't make cuserid visible.
cuserid
C99 math functions are now available.
Two new regnodes have been introduced EXACT_ONLY8, and EXACTFU_ONLY8. They're equivalent to EXACT and EXACTFU, except that they contain a code point which requires UTF-8 to represent/match. Hence, if the target string isn't UTF-8, we know it can't possibly match, without needing to try.
EXACT_ONLY8
EXACTFU_ONLY8
EXACT
EXACTFU
print_bytes_for_locale() is now defined if DEBUGGING, Prior, it didn't get defined unless LC_COLLATE was defined on the platform.
print_bytes_for_locale()
DEBUGGING
LC_COLLATE
If an in-place edit is still in progress during global destruction and the process exit code (as stored in $?) is zero, perl will now treat the in-place edit as successful, replacing the input file with any output produced.
$?
This allows code like:
perl -i -ne 'print "Foo"; last'
to replace the input file, while code like:
perl -i -ne 'print "Foo"; die'
will not. Partly resolves [perl #133659].
A regression in 5.28 caused the following code to fail
close(STDIN); open(CHILD, "|wc -l")'
because the child's stdin would be closed on exec. This has now been fixed.
Fixed an issue where compiling a regexp containing both compile-time and run-time code blocks could lead to trying to compile something which is invalid syntax.
Fixed build failures with -DNO_LOCALE_NUMERIC and -DNO_LOCALE_COLLATE. [perl #133696].
-DNO_LOCALE_NUMERIC
-DNO_LOCALE_COLLATE
Prevent the tests in ext/B/t/strict.t from being skipped. [perl #133713].
/di nodes ending or beginning in s are now EXACTF. We do not want two EXACTFU to be joined together during optimization, and to form a ss, sS, Ss or SS sequence; they are the only multi-character sequences which may match differently under /ui and /di.
/di
EXACTF
ss
sS
Ss
SS
/ui
The upper limit "n" specifiable in a regular expression quantifier of the form "{m,n}" has been doubled to 65534.
"n"
"{m,n}"
The meaning of an unbounded upper quantifier "{m,}" remains unchanged. It matches 2**31 - 1 times on most platforms, and more on ones where a C language short variable is more than 4 bytes long.
"{m,}"
The text above is what perl5294delta should have said. Instead it said "The maximum number of times a pattern can match has been doubled to 65535" That statement was wrong. Try to forget you ever saw it.
Perl 5.29.6 represents approximately 4 weeks of development since Perl 5.29.5 and contains approximately 5,000 lines of changes across 230 files from 19 authors.
Excluding auto-generated files, documentation and release tools, there were approximately 2,600 lines of changes to 150 .pm, .t, .c and .h files.
Perl continues to flourish into its fourth decade thanks to a vibrant community of users and developers. The following people are known to have contributed the improvements that became Perl 5.29.6:
Aaron Crane, Abigail, Dagfinn Ilmari Mannsåker, David Mitchell, Dominic Hargreaves, E. Choroba, Eugen Konkov, H.Merijn Brand, James E Keenan, Jerry D. Hedden, Karen Etheridge, Karl Williamson, Leon Timmermans, Niko Tyni, Petr Písař, Sisyphus, Steve Hay, Tomasz Konojacki, 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 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.
perl -V
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.
If you wish to thank the Perl 5 Porters for the work we had done in Perl 5, you can do so by running the perlthanks program:
perlthanks
This will send an email to the Perl 5 Porters list with your show of thanks.
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.
To install less, copy and paste the appropriate command in to your terminal.
cpanm
cpanm less
CPAN shell
perl -MCPAN -e shell install less
For more information on module installation, please visit the detailed CPAN module installation guide.