delegateIndex = delegates.size();
    }

    @SuppressWarnings("Interruption") // We are propagating an interrupt from a caller.
    private void recordCompletion() {
      if (incompleteOutputCount.decrementAndGet() == 0 && wasCancelled) {
        for (ListenableFuture<? extends T> toCancel : inputFutures) {
          if (toCancel != null) {
            toCancel.cancel(shouldInterrupt);
          }
        }
      }