PERL586DELTA(1)

💖 perl586delta 💖

okay bestie, so this is the tea on what's new for perl v5.8.6 — the manual page is called PERL586DELTA(1) if you're being formal about it, and it lives in the Perl Programmers Reference Guide. grab a snack, we're going through the whole thing 🌸

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✨ NAME ✨

perl586delta — what is new for perl v5.8.6 🎀

💅 DESCRIPTION 💅

This document describes differences between the 5.8.5 release and the 5.8.6 release. it's giving "changelog but make it a whole manual page" and honestly? obsessed. ✨

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🚫 Incompatible Changes 🚫

There are no changes incompatible with 5.8.5. literally none. your code is safe, bestie, breathe 💖

🌈 Core Enhancements 🌈

The perl interpreter is now more tolerant of UTF-16-encoded scripts. slay, it finally stopped being dramatic about them 🦋

On Win32, Perl can now use non-IFS compatible LSPs, which allows Perl to work in conjunction with firewalls such as McAfee Guardian. For full details see the file README.win32, particularly if you're running Win95. yes, Win95 in this economy, we don't make the rules 💀

📦 Modules and Pragmata 📦

• With the base pragma, an intermediate class with no fields used to messes up private fields in the base class. This has been fixed. (yes the original says "messes", we're keeping the lore 🫶)
• Cwd upgraded to version 3.01 (as part of the new PathTools distribution) 🎀
• Devel::PPPort upgraded to version 3.03
• File::Spec upgraded to version 3.01 (as part of the new PathTools distribution) 🎀
• Encode upgraded to version 2.08
• ExtUtils::MakeMaker remains at version 6.17, as later stable releases currently available on CPAN have some issues with core modules on some core platforms. it's not stuck, it's just ✨protecting its peace✨
• I18N::LangTags upgraded to version 0.35
• Math::BigInt upgraded to version 1.73
• Math::BigRat upgraded to version 0.13
• MIME::Base64 upgraded to version 3.05
• POSIX::sigprocmask function can now retrieve the current signal mask without also setting it. main character behavior fr fr 👑
• Time::HiRes upgraded to version 1.65

🛠️ Utility Changes 🛠️

Perl has a new -dt command-line flag, which enables threads support in the debugger. tiny flag, big power 💅

🔥 Performance Enhancements 🔥

reverse sort ... is now optimized to sort in reverse, avoiding the generation of a temporary intermediate list. no more making a whole extra list just to throw it away, we're efficient now ✨

for (reverse @foo) now iterates in reverse, avoiding the generation of a temporary reversed list. same energy, less waste, we love to see it 🌸

🩹 Selected Bug Fixes 🩹

The regexp engine is now more robust when given invalid utf8 input, as is sometimes generated by buggy XS modules. 💀

foreach on threads::shared array used to be able to crash Perl. This bug has now been fixed. no more crashing, we simply don't do that anymore 🙈

A regexp in STDOUT's destructor used to coredump, because the regexp pad was already freed. This has been fixed. that was lowkey haunted ngl 👻

goto & is now more robust — bugs in deep recursion and chained goto & have been fixed. the recursion girlies are finally thriving 🧚

Using delete on an array no longer leaks memory. A pop of an item from a shared array reference no longer causes a leak. no leaks bestie, the memory is staying where it belongs 💜

eval_sv() failing a taint test could corrupt the stack — this has been fixed. taint tests stay winning, stacks stay intact ✅

On platforms with 64 bit pointers numeric comparison operators used to erroneously compare the addresses of references that are overloaded, rather than using the overloaded values. This has been fixed. it was comparing the vibes instead of the values, embarrassing 😭

read into a UTF8-encoded buffer with an offset off the end of the buffer no longer mis-calculates buffer lengths. math girlies rejoice 📐

Although Perl has promised since version 5.8 that sort() would be stable, the two cases sort {$b cmp $a} and sort {$b <=> $a} could produce non-stable sorts. This is corrected in perl5.8.6. a promise is a promise, periodt ✨

Localising $^D no longer generates a diagnostic message about valid -D flags. it can just chill now 🍓

🚨 New or Changed Diagnostics 🚨

For -t and -T,

Too late for "-T" option

has been changed to the more informative

"-T" is on the #! line, it must also be used on the command line

clearer messaging, we love communication in this household 🫶

🧠 Changed Internals 🧠

From now on all applications embedding perl will behave as if perl were compiled with -DPERL_USE_SAFE_PUTENV. See "Environment access" in the INSTALL file for details. 🔍

Most C source files now have comments at the top explaining their purpose, which should help anyone wishing to get an overview of the implementation. documentation era, finally 💖

🧪 New Tests 🧪

There are significantly more tests for the B suite of modules. more tests = more slay, no cap 🎀

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🐛 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 http://bugs.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. You can browse and search the Perl 5 bugs at http://bugs.perl.org/ 🔎

bestie pls trim your bug report. the porting team are not reading your 4000-line paste, and honestly? neither would you 🙈

👀 SEE ALSO 👀

The Changes file for 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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okay that's the whole page, you're officially caught up on perl v5.8.6 💖 this was perl v5.42.3, dated 2026-08-03, and yes that's the manual page PERL586DELTA(1) — mwah, go write some good code, ily 🫶✨🎀