Assignment where comparison was intended¶

ID: cpp/assign-where-compare-meantKind: problemSecurity severity: Severity: errorPrecision: highTags:   - reliability   - correctness   - external/cwe/cwe-481Query suites:   - cpp-security-and-quality.qls

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This rule finds uses of the assignment operator= in places where the equality operator== would make more sense. This is a very common mistake in C and C++, because of the similarity of the= and the== operator, and the fact that theif statement accepts a condition with an integral type, instead of limiting it to just thebool type.

The rule flags every occurrence of an assignment in a position where its result is interpreted as a truth value. An assignment is only flagged if its right hand side is a compile-time constant.

if(p=NULL){//most likely == was intended. Otherwise it evaluates to the value//of the rhs of the assignment (which is NULL)...}