https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110260
Sam James <sjames at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |sjames at gcc dot gnu.org
--- Comment #2 from Sam James <sjames at gcc dot gnu.org> ---
The case I've looked at the most is KWin (https://bugs.gentoo.org/895750) where
we narrowed it down to https://bugs.kde.org/show_bug.cgi?id=460572#c28 with:
"""
To emphasise:
- -O2 -march=x86-64-v3 works
- -O2 -march=x86-64-v4 (or -march=rocketlake) triggers it
"""
It may not be the same as Chiitoo's bug here, but it probably is given the
symptoms are the same & both likely involve AVX512.
I couldn't reproduce it on my machine with AVX512 (only one machine, Tiger
Lake) and couldn't really do any more at that point. I guess a good start would
be seeing what the minimal file(s) required to break kwin are w/ -march=znver4.
