https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117692
Bug ID: 117692 Summary: The VRP pass is introducing new signed integer overflow Product: gcc Version: 15.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: kristerw at gcc dot gnu.org Target Milestone: --- The VRP pass is introducing new signed integer overflow when compiling the following function for X86_64 with -O3: int f4 (int x) { if (x & 7) __builtin_unreachable (); x /= 8; x += 4; return x * 200; } The original function does not invoke UB when called as f4(-85899368), but the VRP pass is changing x_3 = x_2(D) / 8; x_4 = x_3 + 4; _5 = x_4 * 200; return _5; to _7 = x_2(D) * 25; _5 = _7 + 800; return _5; which has a signed overflow for _7 = x_2(D) * 25;