};
    unused = null; // Hint to the JIT that unused is unreachable
    GcFinalization.awaitDone(future);
    assertTrue(future.isDone());
    assertTrue(future.isCancelled());
  }

  public void testAwaitClear() {
    WeakReference<Object> ref = new WeakReference<>(new Object());
    GcFinalization.awaitClear(ref);
    assertThat(ref.get()).isNull();
  }

  public void testAwaitDone_finalizationPredicate() {