The optimization is still valid under -fwrapv semantics. To see this, observe the invariant (0 <= i && i < count) when entering the loop body, and (i==0 || (0 <

The optimization is still valid under -fwrapv semantics. To see this, observe the invariant (0 <= i && i < count) when entering the loop body, and (i==0 || (0 < i && i <= count)) when doing the loop test -- in particular, 0<=i<INT_MAX when entering the loop body (since count <= INT_MAX), so wraparound cannot occur.