https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84841
--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> --- At least latent on the GCC 7 branch and earlier. /* We start expression rewriting from the top statements. So, in this loop we create a full list of statements we will work with. */ stmts[stmt_num - 1] = stmt; for (i = stmt_num - 2; i >= 0; i--) stmts[i] = SSA_NAME_DEF_STMT (gimple_assign_rhs1 (stmts[i+1])); assumes there are no unfolded CST +* CST ops in the IL. OTOH we shouldn't rewrite any exprs with -frounding-math anyway? That is, -fassociative-math and -frounding-math are (again) seemingly in conflict?