mirror of
https://github.com/ethereum/solidity
synced 2023-10-03 13:03:40 +00:00
22 lines
505 B
Solidity
22 lines
505 B
Solidity
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pragma experimental SMTChecker;
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contract C
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{
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function f(uint x, bool b) public pure {
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require(x < 100);
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while (x < 10) {
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if (b)
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x = x + 1;
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else
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x = 0;
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}
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// CHC proves it safe because
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// 1- if it doesn't go in the loop in the first place, x >= 10
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// 2- if it goes in the loop and b == true, x increases until >= 10
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// 3- if it goes in the loop and b == false, it's an infinite loop, therefore
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// the assertion and the error are unreachable.
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assert(x > 0);
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}
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}
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// ----
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