[test-suite][lemon] Avoid UB in hash computations by using unsigned a…#280
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[test-suite][lemon] Avoid UB in hash computations by using unsigned a…#280
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…rithmetic UBSan reports signed overflow in several hash computations in MultiSource/Applications/lemon/lemon.c: - strhash: h = h*13 + *x (line ~4174) - statehash: h = h*571 + a->rp->index*37 + a->dot (line ~4557) - confighash: h = h*571 + a->rp->index*37 + a->dot (line ~4715) - datatype hash: hash = hash*53 + stddt[j] (line ~3409) These use intentional wraparound, but signed overflow is undefined in C. Switch accumulators to unsigned and use unsigned operations so wraparound is well-defined. No functional change is intended beyond removing UB. Signed-off-by: Jerry Zhang Jian <jerry.zhangjian@sifive.com>
nikic
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Aug 29, 2025
| /* Sort the configuration list */ | ||
| void Configlist_sort(){ | ||
| current = (struct config *)msort((char *)current,(char **)&(current->next),Configcmp); | ||
| current = (struct config *)msort((char *)current,(char **)&(current->next),(int(*)(const char*,const char*))Configcmp); |
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Complete the declaration instead of adding casts?
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…rithmetic
UBSan reports signed overflow in several hash computations in MultiSource/Applications/lemon/lemon.c:
These use intentional wraparound, but signed overflow is undefined in C. Switch accumulators to unsigned and use unsigned operations so wraparound is well-defined. No functional change is intended beyond removing UB.