mirror of
https://github.com/ethereum/solidity
synced 2023-10-03 13:03:40 +00:00
25 lines
623 B
Solidity
25 lines
623 B
Solidity
type U8 is uint8;
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using {add as +} for U8 global;
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function add(U8 x, U8 y) pure returns (U8) {
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return U8.wrap(U8.unwrap(x) + U8.unwrap(y)); // overflow detected
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}
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contract C {
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U8 x = U8.wrap(255);
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function inc() public {
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x = x + U8.wrap(1);
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}
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function check() view public {
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U8 y = x;
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assert(U8.unwrap(y) < 256);
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}
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}
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// ====
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// SMTEngine: all
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// ----
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// Warning 4984: (115-142): CHC: Overflow (resulting value larger than 255) happens here.
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// Info 1391: CHC: 1 verification condition(s) proved safe! Enable the model checker option "show proved safe" to see all of them.
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