AUTOSAR C++14 Rule M6-5-3

The loop-counter shall not be modified within condition or statement

Description

The loop-counter shall not be modified within condition or statement.

Rationale

The for loop has a specific syntax for modifying the loop counter. A code reviewer expects modification using that syntax. Modifying the loop counter elsewhere can make the code harder to review.

Polyspace Implementation

The checker flags modification of a for loop counter in the loop body or the loop condition (the condition that is checked to see if the loop must be terminated).

A violation is not reported if the loop condition modifies one field of a structure through a pointer or reference while another field is modified in the loop body.

Troubleshooting

If you expect a rule violation but Polyspace^® does not report it, see Diagnose Why Coding Standard Violations Do Not Appear as Expected.

Check Information

Group: Statements

Category: Required, Automated

PQL Name: std.autosar_cpp14.M6_5_3

Version History

Introduced in R2019a

expand all

R2026a: Violation not reported when loop counter is a field of a referenced structure

Polyspace no longer reports a violation if:

The loop counter is a field in an structure and it is modified through a reference in the loop condition.
The loop body modifies another field of the same structure through the refenrece.

For example, this loop is compliant:

struct Iterator
{
	size_t i;
	size_t j;
};

void foo(Iterator &iterator)
{
	for(; iterator.i < 10; iterator.i++)  // Compliant
	{
		iterator.j++;
	}
}