The requirement for a final default clause is defensive programming. The clause should either take appropriate action, or contain a
suitable comment as to why no action is taken.
Noncompliant Code Example
switch tag { // Noncompliant - default case is missing
case 0, 1, 2, 3:
foo()
case 4, 5, 6, 7:
bar()
}
Compliant Solution
switch tag {
case 0, 1, 2, 3:
foo()
case 4, 5, 6, 7:
bar()
default:
qix()
}
See
- MISRA C:2004, 15.0 - The MISRA C switch syntax shall be used.
- MISRA C:2004, 15.3 - The final clause of a switch statement shall be the default clause
- MISRA C++:2008, 6-4-3 - A switch statement shall be a well-formed switch statement.
- MISRA C++:2008, 6-4-6 - The final clause of a switch statement shall be the default-clause
- MISRA C:2012, 16.1 - All switch statements shall be well-formed
- MISRA C:2012, 16.4 - Every switch statement shall have a default label
- MISRA C:2012, 16.5 - A default label shall appear as either the first or the last switch label of a switch statement
- MITRE, CWE-478 - Missing Default Case in Switch Statement
- CERT, MSC01-C. - Strive for logical completeness