java.lang.IllegalStateException: Terminal event already emitted.

I get the following error when trying to merge a few files using

flatMap(list -> OrderedMerge.create(list, comparator));

where list is a List> .

on version 0.7.9.24 ( I think our RxJava version is too old for the 0.8.x branch ).

`java.lang.IllegalStateException: Terminal event already emitted.
at rx.observables.SyncOnSubscribe$SubscriptionProducer.onError(SyncOnSubscribe.java:476)
at com.github.davidmoten.rx.Serialized$1.next(Serialized.java:65)
at com.github.davidmoten.rx.Serialized$1.next(Serialized.java:47)
at rx.observables.SyncOnSubscribe$SubscriptionProducer.nextIteration(SyncOnSubscribe.java:459)
at rx.observables.SyncOnSubscribe$SubscriptionProducer.slowPath(SyncOnSubscribe.java:437)
at rx.observables.SyncOnSubscribe$SubscriptionProducer.request(SyncOnSubscribe.java:395)
at rx.Subscriber.request(Subscriber.java:157)
at com.github.davidmoten.rx.internal.operators.OrderedMerge$SourceSubscriber.requestMore(OrderedMerge.java:312)
at com.github.davidmoten.rx.internal.operators.OrderedMerge$MergeProducer.emit(OrderedMerge.java:251)
at com.github.davidmoten.rx.internal.operators.OrderedMerge$SourceSubscriber.onNext(OrderedMerge.java:336)
at rx.internal.operators.OperatorCast$CastSubscriber.onNext(OperatorCast.java:69)
at rx.observers.Subscribers$5.onNext(Subscribers.java:235)
at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onNext(OnSubscribeDoOnEach.java:101)
at rx.observables.SyncOnSubscribe$SubscriptionProducer.onNext(SyncOnSubscribe.java:490)
at com.github.davidmoten.rx.Serialized$1.next(Serialized.java:59)
at com.github.davidmoten.rx.Serialized$1.next(Serialized.java:47)
at rx.observables.SyncOnSubscribe$SubscriptionProducer.nextIteration(SyncOnSubscribe.java:459)
at rx.observables.SyncOnSubscribe$SubscriptionProducer.slowPath(SyncOnSubscribe.java:437)
at rx.observables.SyncOnSubscribe$SubscriptionProducer.request(SyncOnSubscribe.java:395)
at rx.Subscriber.setProducer(Subscriber.java:211)
at rx.internal.operators.OperatorCast$CastSubscriber.setProducer(OperatorCast.java:94)
at rx.Subscriber.setProducer(Subscriber.java:205)
at rx.Subscriber.setProducer(Subscriber.java:205)
at rx.observables.SyncOnSubscribe.call(SyncOnSubscribe.java:62)
at rx.observables.SyncOnSubscribe.call(SyncOnSubscribe.java:43)
at rx.Observable.unsafeSubscribe(Observable.java:10151)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
at rx.Observable.unsafeSubscribe(Observable.java:10151)
at rx.internal.operators.OnSubscribeUsing.call(OnSubscribeUsing.java:94)
at rx.internal.operators.OnSubscribeUsing.call(OnSubscribeUsing.java:32)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
at rx.Observable.unsafeSubscribe(Observable.java:10151)
at com.github.davidmoten.rx.internal.operators.OrderedMerge.call(OrderedMerge.java:85)
at com.github.davidmoten.rx.internal.operators.OrderedMerge.call(OrderedMerge.java:27)
at rx.Observable.unsafeSubscribe(Observable.java:10151)
at rx.internal.operators.OperatorMerge$MergeSubscriber.onNext(OperatorMerge.java:251)
at rx.internal.operators.OperatorMerge$MergeSubscriber.onNext(OperatorMerge.java:148)
at rx.internal.operators.OnSubscribeMap$MapSubscriber.onNext(OnSubscribeMap.java:77)
at rx.internal.producers.SingleDelayedProducer.emit(SingleDelayedProducer.java:102)
at rx.internal.producers.SingleDelayedProducer.setValue(SingleDelayedProducer.java:85)
at rx.internal.operators.OperatorToObservableList$1.onCompleted(OperatorToObservableList.java:98)
at rx.internal.operators.OnSubscribeMap$MapSubscriber.onCompleted(OnSubscribeMap.java:97)
at rx.internal.operators.OnSubscribeFromIterable$IterableProducer.fastPath(OnSubscribeFromIterable.java:190)
at rx.internal.operators.OnSubscribeFromIterable$IterableProducer.request(OnSubscribeFromIterable.java:86)
at rx.Subscriber.setProducer(Subscriber.java:211)
at rx.internal.operators.OnSubscribeMap$MapSubscriber.setProducer(OnSubscribeMap.java:102)
at rx.internal.operators.OnSubscribeFromIterable.call(OnSubscribeFromIterable.java:63)
at rx.internal.operators.OnSubscribeFromIterable.call(OnSubscribeFromIterable.java:34)
at rx.Observable.unsafeSubscribe(Observable.java:10151)
at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48)
at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
at rx.Observable.unsafeSubscribe(Observable.java:10151)
at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48)
at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
at rx.Observable.unsafeSubscribe(Observable.java:10151)
at rx.internal.operators.OperatorMerge$MergeSubscriber.onNext(OperatorMerge.java:251)
at rx.internal.operators.OperatorMerge$MergeSubscriber.onNext(OperatorMerge.java:148)
at rx.internal.operators.OnSubscribeMap$MapSubscriber.onNext(OnSubscribeMap.java:77)
at rx.internal.operators.DeferredScalarSubscriber.complete(DeferredScalarSubscriber.java:100)
at rx.internal.operators.DeferredScalarSubscriber.onCompleted(DeferredScalarSubscriber.java:73)
at rx.internal.operators.OperatorBufferWithSize$BufferExact.onCompleted(OperatorBufferWithSize.java:130)
at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onCompleted(OnSubscribeDoOnEach.java:70)
at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onCompleted(OnSubscribeDoOnEach.java:70)
at rx.internal.operators.OperatorMerge$MergeSubscriber.emitLoop(OperatorMerge.java:659)
at rx.internal.operators.OperatorMerge$MergeSubscriber.emit(OperatorMerge.java:571)
at rx.internal.operators.OperatorMerge$InnerSubscriber.onCompleted(OperatorMerge.java:860)
at rx.internal.producers.SingleProducer.request(SingleProducer.java:75)
at rx.Subscriber.setProducer(Subscriber.java:211)
at rx.internal.operators.OperatorSingle$ParentSubscriber.onCompleted(OperatorSingle.java:110)
at rx.internal.operators.DeferredScalarSubscriber.complete(DeferredScalarSubscriber.java:102)
at rx.internal.operators.OnSubscribeTakeLastOne$TakeLastOneSubscriber.onCompleted(OnSubscribeTakeLastOne.java:57)
at rx.internal.operators.OperatorMerge$MergeSubscriber.emitLoop(OperatorMerge.java:659)
at rx.internal.operators.OperatorMerge$MergeSubscriber.emit(OperatorMerge.java:571)
at rx.internal.operators.OperatorMerge$InnerSubscriber.onCompleted(OperatorMerge.java:860)
at rx.internal.operators.OperatorSwitchIfEmpty$ParentSubscriber.onCompleted(OperatorSwitchIfEmpty.java:70)
at rx.internal.operators.OperatorMerge$MergeSubscriber.emitLoop(OperatorMerge.java:659)
at rx.internal.operators.OperatorMerge$MergeSubscriber.emit(OperatorMerge.java:571)
at rx.internal.operators.OperatorMerge$InnerSubscriber.onCompleted(OperatorMerge.java:860)
at rx.internal.operators.OnSubscribeMap$MapSubscriber.onCompleted(OnSubscribeMap.java:97)
at rx.internal.operators.OperatorTake$1.onCompleted(OperatorTake.java:56)
at rx.internal.operators.OnSubscribeFlattenIterable$FlattenIterableSubscriber.checkTerminated(OnSubscribeFlattenIterable.java:308)
at rx.internal.operators.OnSubscribeFlattenIterable$FlattenIterableSubscriber.drain(OnSubscribeFlattenIterable.java:180)
at rx.internal.operators.OnSubscribeFlattenIterable$FlattenIterableSubscriber.onCompleted(OnSubscribeFlattenIterable.java:147)
at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onCompleted(OnSubscribeDoOnEach.java:70)
at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onCompleted(OnSubscribeDoOnEach.java:70)
at rx.internal.operators.OnSubscribeFlattenIterable$FlattenIterableSubscriber.checkTerminated(OnSubscribeFlattenIterable.java:308)
at rx.internal.operators.OnSubscribeFlattenIterable$FlattenIterableSubscriber.drain(OnSubscribeFlattenIterable.java:180)
at rx.internal.operators.OnSubscribeFlattenIterable$FlattenIterableSubscriber.onCompleted(OnSubscribeFlattenIterable.java:147)
at rx.internal.operators.OnSubscribeRedo$4$1.onCompleted(OnSubscribeRedo.java:321)
at rx.internal.operators.OperatorZip$Zip.tick(OperatorZip.java:239)
at rx.internal.operators.OperatorZip$Zip$InnerSubscriber.onCompleted(OperatorZip.java:307)
at rx.internal.operators.OnSubscribeMap$MapSubscriber.onCompleted(OnSubscribeMap.java:97)
at rx.internal.operators.OnSubscribeRedo$3$1.onNext(OnSubscribeRedo.java:298)
at rx.internal.operators.OnSubscribeRedo$3$1.onNext(OnSubscribeRedo.java:284)
at rx.internal.operators.NotificationLite.accept(NotificationLite.java:152)
at rx.subjects.SubjectSubscriptionManager$SubjectObserver.emitNext(SubjectSubscriptionManager.java:255)
at rx.subjects.BehaviorSubject.onNext(BehaviorSubject.java:161)
at rx.observers.SerializedObserver.onNext(SerializedObserver.java:92)
at rx.subjects.SerializedSubject.onNext(SerializedSubject.java:67)
at rx.internal.operators.OnSubscribeRedo$2$1.onCompleted(OnSubscribeRedo.java:228)
at rx.internal.operators.OperatorOnErrorResumeNextViaFunction$4.onCompleted(OperatorOnErrorResumeNextViaFunction.java:101)
at retrofit.RxSupport$2.run(RxSupport.java:57)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)`

it swallows the original Exception:

`java.io.IOException: Stream closed
at java.io.BufferedInputStream.getBufIfOpen(BufferedInputStream.java:170)
at java.io.BufferedInputStream.fill(BufferedInputStream.java:214)
at java.io.BufferedInputStream.read(BufferedInputStream.java:265)
at java.io.ObjectInputStream$PeekInputStream.peek(ObjectInputStream.java:2303)
at java.io.ObjectInputStream$BlockDataInputStream.peek(ObjectInputStream.java:2596)
at java.io.ObjectInputStream$BlockDataInputStream.peekByte(ObjectInputStream.java:2606)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1319)
at java.io.ObjectInputStream.readObject(ObjectInputStream.java:371)
at com.github.davidmoten.rx.Serialized$1.next(Serialized.java:58)
at com.github.davidmoten.rx.Serialized$1.next(Serialized.java:47)
at rx.observables.SyncOnSubscribe$SubscriptionProducer.nextIteration(SyncOnSubscribe.java:459)
at rx.observables.SyncOnSubscribe$SubscriptionProducer.slowPath(SyncOnSubscribe.java:437)
at rx.observables.SyncOnSubscribe$SubscriptionProducer.request(SyncOnSubscribe.java:395)
at rx.Subscriber.request(Subscriber.java:157)
at com.github.davidmoten.rx.internal.operators.OrderedMerge$SourceSubscriber.requestMore(OrderedMerge.java:312)
at com.github.davidmoten.rx.internal.operators.OrderedMerge$MergeProducer.emit(OrderedMerge.java:251)
at com.github.davidmoten.rx.internal.operators.OrderedMerge$SourceSubscriber.onNext(OrderedMerge.java:336)
at rx.internal.operators.OperatorCast$CastSubscriber.onNext(OperatorCast.java:69)
at rx.observers.Subscribers$5.onNext(Subscribers.java:235)
at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onNext(OnSubscribeDoOnEach.java:101)
at rx.observables.SyncOnSubscribe$SubscriptionProducer.onNext(SyncOnSubscribe.java:490)
at com.github.davidmoten.rx.Serialized$1.next(Serialized.java:59)
at com.github.davidmoten.rx.Serialized$1.next(Serialized.java:47)
at rx.observables.SyncOnSubscribe$SubscriptionProducer.nextIteration(SyncOnSubscribe.java:459)
at rx.observables.SyncOnSubscribe$SubscriptionProducer.slowPath(SyncOnSubscribe.java:437)
at rx.observables.SyncOnSubscribe$SubscriptionProducer.request(SyncOnSubscribe.java:395)
at rx.Subscriber.setProducer(Subscriber.java:211)
at rx.internal.operators.OperatorCast$CastSubscriber.setProducer(OperatorCast.java:94)
at rx.Subscriber.setProducer(Subscriber.java:205)
at rx.Subscriber.setProducer(Subscriber.java:205)
at rx.observables.SyncOnSubscribe.call(SyncOnSubscribe.java:62)
at rx.observables.SyncOnSubscribe.call(SyncOnSubscribe.java:43)
at rx.Observable.unsafeSubscribe(Observable.java:10151)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:41)
at rx.internal.operators.OnSubscribeDoOnEach.call(OnSubscribeDoOnEach.java:30)
at rx.Observable.unsafeSubscribe(Observable.java:10151)
at rx.internal.operators.OnSubscribeUsing.call(OnSubscribeUsing.java:94)
at rx.internal.operators.OnSubscribeUsing.call(OnSubscribeUsing.java:32)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
at rx.Observable.unsafeSubscribe(Observable.java:10151)
at com.github.davidmoten.rx.internal.operators.OrderedMerge.call(OrderedMerge.java:85)
at com.github.davidmoten.rx.internal.operators.OrderedMerge.call(OrderedMerge.java:27)
at rx.Observable.unsafeSubscribe(Observable.java:10151)
at rx.internal.operators.OperatorMerge$MergeSubscriber.onNext(OperatorMerge.java:251)
at rx.internal.operators.OperatorMerge$MergeSubscriber.onNext(OperatorMerge.java:148)
at rx.internal.operators.OnSubscribeMap$MapSubscriber.onNext(OnSubscribeMap.java:77)
at rx.internal.producers.SingleDelayedProducer.emit(SingleDelayedProducer.java:102)
at rx.internal.producers.SingleDelayedProducer.setValue(SingleDelayedProducer.java:85)
at rx.internal.operators.OperatorToObservableList$1.onCompleted(OperatorToObservableList.java:98)
at rx.internal.operators.OnSubscribeMap$MapSubscriber.onCompleted(OnSubscribeMap.java:97)
at rx.internal.operators.OnSubscribeFromIterable$IterableProducer.fastPath(OnSubscribeFromIterable.java:190)
at rx.internal.operators.OnSubscribeFromIterable$IterableProducer.request(OnSubscribeFromIterable.java:86)
at rx.Subscriber.setProducer(Subscriber.java:211)
at rx.internal.operators.OnSubscribeMap$MapSubscriber.setProducer(OnSubscribeMap.java:102)
at rx.internal.operators.OnSubscribeFromIterable.call(OnSubscribeFromIterable.java:63)
at rx.internal.operators.OnSubscribeFromIterable.call(OnSubscribeFromIterable.java:34)
at rx.Observable.unsafeSubscribe(Observable.java:10151)
at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48)
at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
at rx.Observable.unsafeSubscribe(Observable.java:10151)
at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:48)
at rx.internal.operators.OnSubscribeMap.call(OnSubscribeMap.java:33)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:48)
at rx.internal.operators.OnSubscribeLift.call(OnSubscribeLift.java:30)
at rx.Observable.unsafeSubscribe(Observable.java:10151)
at rx.internal.operators.OperatorMerge$MergeSubscriber.onNext(OperatorMerge.java:251)
at rx.internal.operators.OperatorMerge$MergeSubscriber.onNext(OperatorMerge.java:148)
at rx.internal.operators.OnSubscribeMap$MapSubscriber.onNext(OnSubscribeMap.java:77)
at rx.internal.operators.DeferredScalarSubscriber.complete(DeferredScalarSubscriber.java:100)
at rx.internal.operators.DeferredScalarSubscriber.onCompleted(DeferredScalarSubscriber.java:73)
at rx.internal.operators.OperatorBufferWithSize$BufferExact.onCompleted(OperatorBufferWithSize.java:130)
at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onCompleted(OnSubscribeDoOnEach.java:70)
at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onCompleted(OnSubscribeDoOnEach.java:70)
at rx.internal.operators.OperatorMerge$MergeSubscriber.emitLoop(OperatorMerge.java:659)
at rx.internal.operators.OperatorMerge$MergeSubscriber.emit(OperatorMerge.java:571)
at rx.internal.operators.OperatorMerge$InnerSubscriber.onCompleted(OperatorMerge.java:860)
at rx.internal.producers.SingleProducer.request(SingleProducer.java:75)
at rx.Subscriber.setProducer(Subscriber.java:211)
at rx.internal.operators.OperatorSingle$ParentSubscriber.onCompleted(OperatorSingle.java:110)
at rx.internal.operators.DeferredScalarSubscriber.complete(DeferredScalarSubscriber.java:102)
at rx.internal.operators.OnSubscribeTakeLastOne$TakeLastOneSubscriber.onCompleted(OnSubscribeTakeLastOne.java:57)
at rx.internal.operators.OperatorMerge$MergeSubscriber.emitLoop(OperatorMerge.java:659)
at rx.internal.operators.OperatorMerge$MergeSubscriber.emit(OperatorMerge.java:571)
at rx.internal.operators.OperatorMerge$InnerSubscriber.onCompleted(OperatorMerge.java:860)
at rx.internal.operators.OperatorSwitchIfEmpty$ParentSubscriber.onCompleted(OperatorSwitchIfEmpty.java:70)
at rx.internal.operators.OperatorMerge$MergeSubscriber.emitLoop(OperatorMerge.java:659)
at rx.internal.operators.OperatorMerge$MergeSubscriber.emit(OperatorMerge.java:571)
at rx.internal.operators.OperatorMerge$InnerSubscriber.onCompleted(OperatorMerge.java:860)
at rx.internal.operators.OnSubscribeMap$MapSubscriber.onCompleted(OnSubscribeMap.java:97)
at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onCompleted(OnSubscribeDoOnEach.java:70)
at rx.internal.operators.OperatorOnErrorResumeNextViaFunction$4.onCompleted(OperatorOnErrorResumeNextViaFunction.java:101)
at rx.internal.operators.OnSubscribeDoOnEach$DoOnEachSubscriber.onCompleted(OnSubscribeDoOnEach.java:70)
at retrofit.RxSupport$2.run(RxSupport.java:57)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)`

Did anyone else experience such an issue?