Subject: bug#78738: (signal nil 5) crashes Emacs

From: Eli Zaretskii <[email-masked]>
Date: Tue, 10 Jun 2025 16:19:38 +0300

> Date: Tue, 10 Jun 2025 12:19:07 +0000
> From: Pip Cet <[email-masked]>
> Cc: Eli Zaretskii <[email-masked]>, [email-masked], [email-masked]
> 
> It's questionable whether all the OOM code we have is still being
> tested, since it's rare to run out of memory nowadays on 64-bit
> machines.

My builds are 32-bit, so I do see it (rarely).

> I run into it once in a while when I've broken something else, just
> like I've never seen a "peculiar error" that wasn't the result of
> messing up Emacs internals elsewhere.

Some users report very large memory footprints of the Emacs process
they sometimes see in a long-running session.

Keep in mind that "memory-full" doesn't mean we exceed the huge 64-bit
address space, just the total VM of the system, which is still
possible, even in a 64-bit build, especially if the amount of swap is
configured sub-optimally.