https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108459
--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> --- Slightly simplified: void foo (int x) { #pragma omp for collapse(2) for (int i = 1; i <= 16; i++) for (int j = i * x; j <= 16; j++) ; } Started with my r11-2537-g29e0ad452cdf001bcc commit, will have a look.