[previous] MISRA-C:2004  Rule  14.2:  (Required) [next] All non-null statements shall either (i) have at least one side effect however executed, or (ii) 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: 

/* 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.

QAC messages that encompass this guideline:

3110 The left-hand operand of this ',' has no side effects.
3112 This statement has no side-effect - it can be removed.
3425 One branch of this conditional operation is a redundant expression.
3426 Right hand side of comma expression has no side effect and its value is not used.
3427 Right hand side of logical operator has no side effect and its value is not used.


(c) The Motor Industry Research Association, 2004
QA C Source Code Analyser 8.1.2
MISRA-C:2004 Compliance Module 3.2
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