pragma experimental SMTChecker; contract C { function f(uint8 x) public pure returns (uint) { x = 0; uint8 y = x - 1; assert(y == 255); y = x - 255; assert(y == 1); return y; } } // ---- // Warning 3944: (117-122): CHC: Underflow (resulting value less than 0) happens here. // Warning 3944: (150-157): CHC: Underflow (resulting value less than 0) happens here.