[Bug libstdc++/97944] 30_threads/jthread/95989.cc fails randomly

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=97944

--- Comment #8 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Christophe Lyon from comment #0)
> Since this new test was introduced, it fails randomly on arm, aarch64 and
> other targets (apparently powerpc, ia64, m68k according to gcc-testresults).

And hppa64-hp-hpux11.11
https://gcc.gnu.org/pipermail/gcc-testresults/2020-November/630265.html

I still haven't reproduced this, despite trying repeatedly on two different
aarch64-unknown-gnu-linux hosts (a weedy pine64 and a faster qemu vm) and
hundreds of times on powerpc64le and x86_64. Frustrating.