PERL5223DELTA(1perl)

📦

version 5.44.0 · 2 versions

5.44.0 · arch rolling (latest)
5.42.3 · arch rolling

✨ perl5223delta — the tea on Perl v5.22.3 ✨

okay bestie, this one lives in the Perl Programmers Reference Guide (it's PERL5223DELTA(1perl) if you're being formal about it) and it's literally just the glow-up notes for perl v5.22.3. sit down, hydrate, let's go 💖

🌸 NAME 🌸

perl5223delta — what is new for perl v5.22.3 💅

🦋 DESCRIPTION 🦋

This doc spills the differences between the 5.22.2 release and the 5.22.3 release. that's it, that's the vibe.

If you're upgrading from something even older, like 5.22.1, be a good student and read perl5222delta first — it's got the 5.22.1 → 5.22.2 differences. no skipping chapters ✨

🔒 Security 🔒

🚨 `-Di` switch is now required for PerlIO debugging output

ngl, previously PerlIO debugging output would just get yeeted to the file named by the PERLIO_DEBUG environment variable — as long as perl wasn't running setuid and the -T or -t switches hadn't been parsed yet. 😭

and here's the messy part: if perl did output at a point where it hadn't yet parsed its switches, this could result in perl creating or overwriting the file named by PERLIO_DEBUG — even when the -T switch had been supplied. not the moment, honestly.

So now? Perl requires the -Di switch to produce PerlIO debugging output. By default this is written to stderr, but you can optionally redirect it to a file by setting the PERLIO_DEBUG environment variable. cute and controlled 💅

heads up: if perl is running setuid, or the -T switch was supplied, then PERLIO_DEBUG is ignored and the debugging output goes to stderr — same as for any other -D switch.

🔐 Core modules and tools no longer search `.` for optional modules

The tools and many modules supplied in core no longer search the default current directory entry in @INC for optional modules. For example, Storable will remove the final . from @INC before trying to load Log::Agent. periodt.

Why do we care? Because this prevents an attacker injecting an optional module into a process run by another user where the current directory is writable by the attacker — e.g. the /tmp directory. that's the whole plot twist. 🕵️♀️

In most cases this removal should not cause problems, but difficulties were encountered with base, which treats every module name supplied as optional. These difficulties have not yet been resolved, so for this release there are no changes to base. We hope to have a fix for base in Perl 5.22.4. 🤞

To protect your own code from this attack, either remove the default "." entry from @INC at the start of your script — so:

#!/usr/bin/perl
use strict;
...

becomes:

#!/usr/bin/perl
BEGIN { pop @INC if $INC[-1] eq '.' }
use strict;
...

or for modules, remove "." from a localized @INC, so:

my $can_foo = eval { require Foo; }

becomes:

my $can_foo = eval {
    local @INC = @INC;
    pop @INC if $INC[-1] eq '.';
    require Foo;
};

💀 Incompatible Changes 💀

Other than the security changes above, there are no changes intentionally incompatible with Perl 5.22.2. If any exist, they are bugs, and we request that you submit a report. See "Reporting Bugs" below. iykyk 🫶

📦 Modules and Pragmata 📦

⭐ Updated Modules and Pragmata

Archive::Tar has been upgraded from version 2.04 to 2.04_01.
bignum has been upgraded from version 0.39 to 0.39_01.
CPAN has been upgraded from version 2.11 to 2.11_01.
Digest has been upgraded from version 1.17 to 1.17_01.
Digest::SHA has been upgraded from version 5.95 to 5.95_01.
Encode has been upgraded from version 2.72 to 2.72_01.
ExtUtils::Command has been upgraded from version 1.20 to 1.20_01.
ExtUtils::MakeMaker has been upgraded from version 7.04_01 to 7.04_02.
File::Fetch has been upgraded from version 0.48 to 0.48_01.
File::Spec has been upgraded from version 3.56_01 to 3.56_02.
HTTP::Tiny has been upgraded from version 0.054 to 0.054_01.
IO has been upgraded from version 1.35 to 1.35_01.
The IO-Compress modules have been upgraded from version 2.068 to 2.068_001.
IPC::Cmd has been upgraded from version 0.92 to 0.92_01.
JSON::PP has been upgraded from version 2.27300 to 2.27300_01.
Locale::Maketext has been upgraded from version 1.26 to 1.26_01.
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 5.20160429 to 5.20170114_22.
Net::Ping has been upgraded from version 2.43 to 2.43_01.
Parse::CPAN::Meta has been upgraded from version 1.4414 to 1.4414_001.
Pod::Html has been upgraded from version 1.22 to 1.2201.
Pod::Perldoc has been upgraded from version 3.25 to 3.25_01.
Storable has been upgraded from version 2.53_01 to 2.53_02.
Sys::Syslog has been upgraded from version 0.33 to 0.33_01.
Test has been upgraded from version 1.26 to 1.26_01.
Test::Harness has been upgraded from version 3.35 to 3.35_01.
XSLoader has been upgraded from version 0.20 to 0.20_01, fixing a security hole in which binary files could be loaded from a path outside of @INC. [GH #15418] <https://github.com/Perl/perl5/issues/15418> 🔥 that last one is giving hero behavior

📚 Documentation 📚

📝 Changes to Existing Documentation

perlapio

The documentation of "PERLIO_DEBUG" has been updated.

perlrun

The new -Di switch has been documented, and the documentation of "PERLIO_DEBUG" has been updated.

🧪 Testing 🧪

A new test script, t/run/switchDx.t, has been added to test that the new -Di switch is working correctly. slay, testing is self-care 💖

🐛 Selected Bug Fixes 🐛

The "PadlistNAMES" macro is an lvalue again. (it said "not today" to being an rvalue, iconic honestly)

👑 Acknowledgements 👑

Perl 5.22.3 represents approximately 9 months of development since Perl 5.22.2 and contains approximately 4,400 lines of changes across 240 files from 20 authors. the way that's a whole pregnancy of code 😭

Excluding auto-generated files, documentation and release tools, there were approximately 2,200 lines of changes to 170 .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 5.22.3:

Aaron Crane, Abigail, Alex Vandiver, Aristotle Pagaltzis, Chad Granum, Chris 'BinGOs' Williams, Craig A. Berry, David Mitchell, Father Chrysostomos, James E Keenan, Jarkko Hietaniemi, Karen Etheridge, Karl Williamson, Matthew Horsfall, Niko Tyni, Ricardo Signes, Sawyer X, Stevan Little, Steve Hay, 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.

🐞 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. accuracy is the assignment ✨

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.

and that's the whole page bestie 🎀 no notes, we ate — this was perl v5.44.0, dated 2026-10-17, filed under PERL5223DELTA(1perl). go forth and upgrade responsibly 💅💖

📦 where this page comes from

arch rolling: perl 5.44.0-1 · Artistic-1.0-Perl AND GPL-1.0-or-later
💖 girlified by deepseek-ai/DeepSeek-V4.1-Flash on 2026-11-03: a language model's rewrite of the original, under its terms