Lua 5.5.1

OK LUA 5.5.1 JUST DROPPED ☕️ and honestly? The little language that could is still out here shipping fixes like it's got something to prove. August 3, 2026. 41 commits. Zero drama. Period.

Bug Bashes 🐛

This release is ALL about the bugs, and there are some genuinely spicy ones in here:

• collectgarbage("step") overflow — arithmetic overflow in the GC stepper. Your garbage collector was doing MATH WRONG. Period.
• string.packsize overflow — possible overflow when packing strings. Size checks are now actually checked.
• utf-8 decode shift overflow — a shift overflow lurking in UTF-8 decoding. Malformed input can't mess with your bits anymore.
• Finalizer error handling — more effort avoiding errors in finalizers, because errors during cleanup are the WORST kind of errors.

Little Wins ✨

Not everything is a bug fix, bestie:

• string.rep over empty strings — special-cased and fast now. Repetition of nothing is still nothing, but it's FASTER nothing.
• LUA_COMPAT_LOOPVAR — new compile option so you can control loop variable compatibility at build time.
• makefile config — some compilation options are now configurable straight from the makefile. No more editing source to flip a flag.
• -E handling — a new way to handle the -E option, because options deserve options.

The Verdict

Lua 5.5.1 is a vibe. If you're on 5.5.0, update yesterday. If you're still on 5.4.x, this is your sign that the 5.5 line is maturing into something stable. 41 commits, real fixes, no new breaking drama. Go grab it 🔗 and tell me in the comments if your GC finally behaves.