[previous] 3343 [next] Logical NOT being performed on one operand of a comparison.
Arithmetic type - Operations REFERENCE - ISO:C90-6.3.3.3 Unary Arithmetic Operators

A logical NOT operator (!) has been applied to one operand of an equality operator (== or !=). This is a strange construct and probably a mistake. If both operands are effectively Boolean, i.e. they have values of either 0 or 1, the expression would be more readable if rewritten.

For example, in the following code, if "a" and "b" are Boolean values, the "if" expression in function "f1" evaluates as true if ... The statement would be more readable if rewritten as in function "f2" 


/*PRQA S 2017,3227,3408 ++*/

extern int f1(int a, int b)
{
    int r = 0;

    if (!a == b)                    /* Message 3343 */
    {
        r = 1;
    }

    return r;
}

extern int f2(int a, int b)
{
    int r = 0;

    if (a != b)                     /* OK */
    {
        r = 1;
    }

    return r;
}

No MISRA-C:2004 Rules applicable to message 3343

QA·C Source Code Analyser 8.1
MISRA-C:2004 Compliance Module 3.2
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