Unreachable statement¶
ID: js/unreachable-statement
Kind: problem
Security severity:
Severity: warning
Precision: very-high
Tags:
- quality
- reliability
- correctness
- external/cwe/cwe-561
Query suites:
- javascript-security-and-quality.qls
Click to see the query in the CodeQL repository
An unreachable statement almost always indicates missing code or a latent bug and should be examined carefully.
Recommendation¶
Examine the surrounding code to determine why the statement has become unreachable. If it is no longer needed, remove the statement.
Example¶
In the following example, a spurious semicolon after the if condition at line 2 makes the return statement on line 4 unreachable: the function will always execute the return statement on line 3 first, so it will never reach line 4.
function f() {
if (someCond());
return 23;
return 42;
}
To correct this issue, remove the spurious semicolon:
function f() {
if (someCond())
return 23;
return 42;
}
References¶
Wikipedia: Unreachable code.
Common Weakness Enumeration: CWE-561.