bug#68940: 29.2; Random crashes in face for char / font

[Robert Vojta]

> Did you clean up the source tree before rebuilding?  At least
> "make distclean" is needed.

Yes. When rebuilding, it's always - distclean, configure, make, ...

> Did you try --debug-init?

Yes, many times, even with the loop & llvm --batch.

With --debug-init, the crash, or the invalid character, ... all the
issues from this thread / bug never happened, not even once.

> I don't see why it could be undefined.

Just a wild guess after seeing all this randomness.

> I'm beginning to suspect some problem with your compiler or maybe even
> with hardware (like some memory chip?).

Using Apple clang version 15.0.0 (clang-1500.1.0.2.5). All the issues
are happening with the binary I downloaded from
https://emacsformacosx.com/ too. Went to the source only to be able to
turn off optimizations, include debug info, ...

Might be a HW problem, will run a full HW test too.

Sorry for the noise so far, this randomness drives me crazy, and the
only thing exhibiting it is Emacs, rest is doing fine.