https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85582
Bug ID: 85582 Summary: wrong code at -O1 and above on x86_64-linux-gnu in 32-bit mode Product: gcc Version: unknown Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: su at cs dot ucdavis.edu Target Milestone: --- $ gcctk -v Using built-in specs. COLLECT_GCC=gcctk COLLECT_LTO_WRAPPER=/home/su/software/tmp/gcc/gcc-trunk/libexec/gcc/x86_64-pc-linux-gnu/9.0.0/lto-wrapper Target: x86_64-pc-linux-gnu Configured with: ../gcc-source-trunk/configure --enable-languages=c,c++,lto --prefix=/home/su/software/tmp/gcc/gcc-trunk --disable-bootstrap Thread model: posix gcc version 9.0.0 20180501 (experimental) [trunk revision 259787] (GCC) $ $ gcctk -m32 -O0 small.c; ./a.out $ $ gcctk -m32 -O1 small.c $ ./a.out Floating point exception (core dumped) $ --------------------------------- int a, b, d = 2, e; long long c = 1; int main () { int g = 6; L1: e = d; if (a) goto L1; g--; int i = c >> ~(~e | ~g); L2: c = (b % c) * i; if (!e) goto L2; return 0; }