Fix a bug where ::warning() was called with a va_list argument instead of an actual vararg list. Also cleaned up the format for warnings. (Previously some would start with "warning - warning - Warning:" which was a bit redundant)

void main()
{
    S t;
}

struct T
{
    int i;
    S* s;
}

struct S
{
    long i;
    T* t;
}