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From: "bartoldeman at users dot sourceforge.net" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/101683] Floating point exception for
 double->unsigned conversion on avx512 only
Date: Fri, 30 Jul 2021 11:25:42 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D101683

--- Comment #6 from bartoldeman at users dot sourceforge.net ---
"really not many people care about floating point exceptions". I think more
people should :) but this is indeed the context.

We found this issue on a supercomputer running OpenFOAM (which can enable FP
exceptions, see https://cpp.openfoam.org/v3/a02284.html), and a small simple
MPI program with FP exceptions enabled. Even then it crashed in an underlyi=
ng
library, and not OpenFOAM itself, see
https://github.com/ComputeCanada/software-stack/issues/74

In the end the combination of MPI and FP exceptions easily triggers it, but=
 the
vast majority of jobs don't crash, so even on our cluster this is very rare
indeed. And many other clusters don't compile the UCX library with avx512
optimizations enabled or use precompiled binaries without those enabled.=