if (VM.VerifyAssertions) VM._assert(t >= 0);
if (VM_Interface.VerifyAssertions) VM_Interface._assert(t >= 0);
  public void setTarget (int t) {    VM_Magic.isync();    if (VM.VerifyAssertions) VM._assert(t >= 0);    target = t + 1;    VM_Magic.sync();  }