what happened to the reachability diag ?

[Basile B.]

I've been away of D since a while but I'm surprised to see DMD 
accepting this input without any **warning**s

```d
module runnable;

void main() nothrow  // no landing pad
{
     enum E {e0}
     E e;
     final switch (e)
     {
         case E.e0: goto case E.e0;
     }
     return; // statement not reachable
}

void other() nothrow // no landing pad
{
     enum E {e0}
     E e;
     final switch (e)
     {
         case E.e0: goto case E.e0;
     }
     int a; // declaration not reachable
}

int shoudlebeLike()
{
     assert(0)  ;
     while (true)
     {
         other();
     }
     assert(0);
     other();
     return 0;
}
```

(tried with -w -wi, etc).