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IAR Embedded Workbench for RX 5.20

SIZEOF-side-effect

In this section:
Synopsis

sizeof expressions containing side effects

Enabled by default

Yes

Severity/Certainty

Medium/Medium

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Full description

The sizeof operator is used on an expression that contains side effects. Because sizeof only operates on the type of the expression, the expression itself is not evaluated, which it probably was meant to be. This check is identical to MISRAC2004-12.3, MISRAC++2008-5-3-4.

Coding standards
CERT EXP06-C

Operands to the sizeof operator should not contain side effects

CERT EXP06-CPP

Operands to the sizeof operator should not contain side effects

MISRA C:2004 12.3

(Required) The sizeof operator shall not be used on expressions that contain side effects.

MISRA C++ 2008 5-3-4

(Required) Evaluation of the operand to the sizeof operator shall not contain side effects.

Code examples

The following code example fails the check and will give a warning:

void example(void) {
	int i;
	int size = sizeof(i++);
}

The following code example passes the check and will not give a warning about this issue:

void example(void) {
	int i;
	int size = sizeof(i);
	i++;
}