Try something like this with optimization on: int would_increment_overflow(int a) { if (a + 1 < a) { return -1; return 0; } This get

Try something like this with optimization on: int would_increment_overflow(int a) { if (a + 1 < a) { return -1; return 0; } This gets turned to a function that always returns 0. 0000000000000000 <would_increment_overflow>: 0: f3 0f 1e fa endbr64 4: 31 c0 xor %eax,%eax 6: c3 retq Using unsigned int gives the wrapping semantics.