void enqueue (VM_Proxy p) { if (head == null) { head = p; } else { tail.waitingNext = p; } tail = p;
void enqueue (VM_Thread t) { enqueue(t.proxy);
  void enqueue (VM_Proxy p) {    if (head == null) {      head = p;    } else {      tail.waitingNext = p;    }    tail = p;  }