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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/107608] [13 Regression] Failure on
 fold-overflow-1.c and pr95115.c
Date: Thu, 12 Jan 2023 12:03:51 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D107608

--- Comment #27 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
"elide an overflow" should be probably "elide an overflow or division by ze=
ro"
I think,
because finite / 0.0 returns infinity and raises FE_DIVBYZERO rather than
FE_OVERFLOW,
even when it returns infinity from finite operands.
Seems for infinity / 0.0 no exception is raised, so the finite operands
infinite result condition seems to be sufficient.

For GCC 13, I think it is important that we e.g. don't miscompile glibc lib=
m,
so
the libm testsuite should be clean.  PR107967 fixed some of the failures, a=
nd
some were claimed to be dups of this PR.  So, would be nice to test GCC with
your patch on glibc + libm testsuite.
Just
CC=3D/path/to/patched-gcc-trunk/gcc CXX=3D/path/to/patched-gcc-trunk/g++
../configure --prefix=3D/usr
CC=3D/path/to/patched-gcc-trunk/gcc CXX=3D/path/to/patched-gcc-trunk/g++ ma=
ke -jN
CC=3D/path/to/patched-gcc-trunk/gcc CXX=3D/path/to/patched-gcc-trunk/g++ ma=
ke -jN
check
should be enough in latest glibc (and perhaps compare that to GCC 12).=