Synopsis

(Required) Operands shall not be of an inappropriate essential type. An operand of essentially unsigned typed is used as the operand to the unary minus operator. This is problematic because the signedness of the result is determined by the implementation-defined size of int.

Enabled by default

Yes

Severity/Certainty

Medium/Medium

Full description

An operand of essentially unsigned typed is used as the operand to the unary minus operator. This check is identical to MISRAC++2008-5-3-2, MISRAC2004-12.9, MISRAC++2023-8.3.1.

Coding standards

Code examples

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

void example(void) {
	unsigned int max = -1U;
	// use max = ~0U;
}

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

void example(void) {
	int neg_one = -1;
}