DMD 2.060:

enum E{ v }
template Seq(T...){ alias T Seq; }
int foo(){
    E e;
    final switch(e){
        if(e) case E.v: return 0;
    }
    final switch(e)
    foreach(x;Seq!(E.v))
    case x: return 0;
}

Error: function foo no return exp; or assert(0); at end of function

The code should compile.