How do explicit casts of arguments affect 21.15 (amendment 1)?

[misra-c]

Rule 21.15 applies to the types after casting.

Code:

void f(signed char* a, int* b, size_t n) {
    memcmp(a, a, n);                   // Compliant
    memcmp(b, b, n);                   // Compliant
    memcmp((int*)b, (int*)b, n);       // Compliant
    memcmp((int*)a, (int*)a, n);       // Compliant - but violates Rule 11.3
    memcmp(a, b, n);                   // Non-Compliant
    memcmp((int*)a, b, n);             // Compliant - but violates Rule 11.3
    memcmp((float*)a, (float*)b, n);   // Compliant - but violates Rules 11.3 and  21.16
    memcmp((short*)a, a, n);           // Non-Compliant - and also violates Rule 11.3
}