Bad check for oddness¶

ID: cpp/incomplete-parity-checkKind: problemSecurity severity: Severity: warningPrecision: mediumTags:   - reliability   - correctness   - typesQuery suites:   - cpp-security-and-quality.qls

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This rule finds code that usesx%2==1 to check whether a numberx is odd, which does not work for negative numbers. Applying% to negative numbers produces negative results. For example,(-5)%2 equals-1, not1. As a result, this check incorrectly considers all negative numbers as even.