return new Exiter(Runtime.getRuntime());
  }

  @VisibleForTesting
  static final class Exiter implements UncaughtExceptionHandler {
    private static final LazyLogger logger = new LazyLogger(Exiter.class);

    private final Runtime runtime;

    Exiter(Runtime runtime) {
      this.runtime = runtime;
    }

    @Override
    public void uncaughtException(Thread t, Throwable e) {

    return new Exiter(Runtime.getRuntime());
  }

  @VisibleForTesting
  static final class Exiter implements UncaughtExceptionHandler {
    private static final LazyLogger logger = new LazyLogger(Exiter.class);

    private final Runtime runtime;

    Exiter(Runtime runtime) {
      this.runtime = runtime;
    }

    @Override
    public void uncaughtException(Thread t, Throwable e) {

 */
@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
public final class ExecutionList {
  /** Logger to log exceptions caught when running runnables. */
  private static final LazyLogger log = new LazyLogger(ExecutionList.class);

  /**
   * The runnable, executor pairs to execute. This acts as a stack threaded through the {@link
   * RunnableExecutorPair#next} field.
   */
  @GuardedBy("this")
  @CheckForNull

  @CheckForNull private volatile Set<Throwable> seenExceptions = null;

  private volatile int remaining;

  private static final AtomicHelper ATOMIC_HELPER;

  private static final LazyLogger log = new LazyLogger(AggregateFutureState.class);

  static {
    AtomicHelper helper;
    Throwable thrownReflectionFailure = null;
    try {
      helper =
          new SafeAtomicHelper(

  @CheckForNull private volatile Set<Throwable> seenExceptions = null;

  private volatile int remaining;

  private static final AtomicHelper ATOMIC_HELPER;

  private static final LazyLogger log = new LazyLogger(AggregateFutureState.class);

  static {
    AtomicHelper helper;
    Throwable thrownReflectionFailure = null;
    try {
      helper =
          new SafeAtomicHelper(

@J2ktIncompatible
@GwtIncompatible
@ElementTypesAreNonnullByDefault
final class ListenerCallQueue<L> {
  // TODO(cpovirk): consider using the logger associated with listener.getClass().
  private static final LazyLogger logger = new LazyLogger(ListenerCallQueue.class);

  // TODO(chrisn): promote AppendOnlyCollection for use here.
  private final List<PerListenerQueue<L>> listeners =