2019-02-06 10:12:02 +00:00
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pragma experimental SMTChecker;
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contract C
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{
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function f(int8 x) public pure returns (int8) {
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x = -2;
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int8 y = x - 127;
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assert(y == 127);
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x = -128;
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y = x - 127;
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assert(y == 1);
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x = 127;
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y = x - (-127);
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assert(y == -2);
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return y;
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}
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}
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// ----
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2020-12-02 17:40:48 +00:00
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// Warning 3944: (116-123): CHC: Underflow (resulting value less than -128) happens here.\nCounterexample:\n\nx = (- 2)\n = 0\n\nTransaction trace:\nconstructor()\nf(0)
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// Warning 3944: (163-170): CHC: Underflow (resulting value less than -128) happens here.\nCounterexample:\n\nx = (- 128)\n = 0\n\nTransaction trace:\nconstructor()\nf(0)
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// Warning 4984: (207-217): CHC: Overflow (resulting value larger than 127) happens here.\nCounterexample:\n\nx = 127\n = 0\n\nTransaction trace:\nconstructor()\nf(0)
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