Accessing a volatile has potential side effects, beyond the simple read operation - hence the violation of Rule 13.3.
x += 1 does not violate Rule 13.3, because that Rule explicitly only applies to ++ and --, and not to += or -=
x += 1 does not violate Rule 13.3, because that Rule explicitly only applies to ++ and --, and not to += or -=
Posted by and on behalf of the MISRA C Working Group