MISRA.STMT.NO_EFFECT

The statement has no side effects, and does not change control flow.

MISRA-C Rule 14.2 (required): All non-null statements shall either: (a) have at least one side-effect however executed, or (b) cause control flow to change.

Any statement (other than a null statement) which has no side-effect and does not result in a change of control flow will normally indicate a programming error, and therefore a static check for such statements shall be performed. For example, the following statements do not necessarily have side effects when executed:

Example

/* assume uint16_t x;
   and uint16_t i; */
...
x >= 3u; /* not compliant: x is compared to 3,
            and the answer is discarded */

Note that "null statement" and "side effect" are defined in ISO/IEC 9899:1990 [2] sections 6.6.3 and 5.1.2.3 respectively.