Redundant null check due to previous dereference¶
ID: cpp/redundant-null-check-simpleKind: path-problemSecurity severity: 7.5Severity: errorPrecision: highTags: - reliability - correctness - security - external/cwe/cwe-476Query suites: - cpp-code-scanning.qls - cpp-security-extended.qls - cpp-security-and-quality.qls
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This rule finds comparisons of a pointer to null that occur after a reference of that pointer. It’s likely either the check is not required and can be removed, or it should be moved to before the dereference so that a null pointer dereference does not occur.
Recommendation¶
The check should be moved to before the dereference, in a way that prevents a null pointer value from being dereferenced. If it’s clear that the pointer cannot be null, consider removing the check instead.
Example¶
intf(MyList*list){list->append(1);// ...if(list!=NULL){list->append(2);}}
References¶
Common Weakness Enumeration:CWE-476.