https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83298
Bug ID: 83298 Summary: wrong code at -O1, -O2 and -O3 on x86_64-linux-gnu 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: --- This appears to be a recent regression. $ 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/8.0.0/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 8.0.0 20171205 (experimental) [trunk revision 255434] (GCC) $ $ gcctk -O0 small.c; ./a.out $ gcc-7.2.0 -O1 small.c; ./a.out $ $ gcctk -O1 small.c $ ./a.out Aborted (core dumped) $ -------------------------------- int a, b, c = 1; int main () { for (; b < 1; b++) ; if (!(c * (a < 1))) __builtin_abort (); return 0; }