Synopsis

Do not add or subtract an integer to a pointer to a non-array object.

Enabled by default

Yes

Severity/Certainty

Medium/Medium

Full description

Pointer arithmetic must be performed only on pointers that reference elements of array objects.

Coding standards

Code examples

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

struct numbers {
    short num_a, num_b, num_c;
};

int sum_numbers(const struct numbers *numb){
    int total = 0;
    const short *numb_ptr;

    for (numb_ptr = &numb->num_a;
            numb_ptr <= &numb->num_c;
            numb_ptr++) {
        total += *(numb_ptr);
    }

    return total;
}

int main(void) {
    struct numbers my_numbers = { 1, 2, 3 };
    sum_numbers(&my_numbers);
    return 0;
}

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

struct numbers {
  short num_a, num_b, num_c;
};
void example(const struct numbers *numb) {
  int total = numb->num_a + numb->num_b + numb->num_c;
}