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In this noncompliant code example, the comparison of a to b has no effect.

int a;
int b;
/* ... */
a == b;

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The assignment of b to a is now properly performed.

int a;
int b;
/* ... */
a = b;

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In this example, a pointer increment and then a dereference occurs. However, the dereference has no effect.

int *p;
/* ... */
*p++;

Compliant Solution (Dereference)

Correcting this example depends on the intent of the programmer. For instance, if dereferencing p was a mistake, then p should not be dereferenced.

int *p;
/* ... */
p++;

If the intent was to increment the value referred to by p, then parentheses can be used to ensure p is dereferenced and then incremented. (See recommendation EXP00-C. Use parentheses for precedence of operation.)

int *p;
/* ... */
(*p)++;

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Another possibility is that p is being used to reference a memory-mapped device. In this case, the variable p should be declared as volatile.

volatile int *p;
/* ... */
(void) *p++;

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