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)

interface IN
{
    void func();
}
abstract class AC
{
    abstract void func();
    long ll;
}
class C : AC
{
    void func()
    {
    }
}

void main()
{
    scope c = new C;
}