retroarch's runaway logs on mGBA package

Is there an existing issue for this?

• This is a bug in RetroArch frontend
• I have searched the existing issues

Description

I logged in today to find a disk space warning. After a few minutes of investigating, I discovered that retroarch has been saving really big log files over the past few days. The last couple days have been 20gb files (each) and the day before that 5gb files. I can't really say what's in the files because I don't have 20gb of RAM to open the file. However, I'm guessing this isn't expected behaviour.

I know that this only happens on the mGBA package because the genesisplusgx, nestopia, snes9x and beetle-pce generate files of few kb each, as they should.

For obvious reasons, I can't keep all of these massive log files, but I'll try to keep the latest one if there's some sort of grep you want me to run on them.

Expected behavior

No response

Steps to reproduce the bug

1. Launch game that uses mGBA core
2. Play for an hour or two
3. Go to ~/.config/retroarch/logs
4. Observe massive files

Version/Commit

1.22.2 (Git b2ceb50) Dec 20 2025

Bisect Results

No response

Present in the nightly version

I don't know

Platform & operating system

Debian testing

Affected Cores

mgba 0.10.5+dfsg-3+b1

Environment information

No response

Relevant log output

Too big.

Reproduce by launching a game with the mGBA core for an hour or two, then inspect ~/.config/retroarch/logs and compare the generated files with other cores. The issue is done when an mGBA run no longer produces runaway multi-gigabyte logs and the resulting log output remains usable.