Dead code due to goto or break statement¶
ID: cpp/dead-code-goto
Kind: problem
Security severity:
Severity: warning
Precision: high
Tags:
- maintainability
- external/cwe/cwe-561
Query suites:
- cpp-security-and-quality.qls
Click to see the query in the CodeQL repository
Code immediately following a goto
or break
statement will not be executed, unless there is a label or switch case. When the code is necessary, this leads to logical errors or resource leaks. If the code is unnecessary, it may confuse readers.
Recommendation¶
If the unreachable code is necessary, move the goto
or break
statement to after the code. Otherwise, delete the unreachable code.
Example¶
goto err1;
free(pointer); // BAD: this line is unreachable
err1: return -1;
free(pointer); // GOOD: this line is reachable
goto err2;
err2: return -1;
References¶
The CERT C Secure Coding Standard: MSC12-C. Detect and remove code that has no effect or is never executed.
Common Weakness Enumeration: CWE-561.