solidity/test/libsolidity/smtCheckerTests/overflow/overflow_sum.sol
2020-12-09 19:55:18 +01:00

20 lines
738 B
Solidity

pragma experimental SMTChecker;
contract C
{
function f(uint8 x) public pure returns (uint8) {
uint8 y = x + 255;
require(y >= x);
x = 255;
y = x + 1;
assert(y == 0);
y = x + 255;
assert(y == 254);
return y;
}
}
// ----
// Warning 4984: (109-116): CHC: Overflow (resulting value larger than 255) happens here.\nCounterexample:\n\nx = 1\n = 0\n\nTransaction trace:\nconstructor()\nf(1)
// Warning 4984: (154-159): CHC: Overflow (resulting value larger than 255) happens here.\nCounterexample:\n\nx = 255\n = 0\n\nTransaction trace:\nconstructor()\nf(0)
// Warning 4984: (185-192): CHC: Overflow (resulting value larger than 255) happens here.\nCounterexample:\n\nx = 255\n = 0\n\nTransaction trace:\nconstructor()\nf(0)