[2.1.11] NPE in SpscLinkedArrayQueue.lvElement

I’ve seen already a couple of those after upgrading. Unfortunately I cannot give you any reproduction as I have zero idea where it might come from but here are a couple of stacktraces:

java.lang.NullPointerException
 at io.reactivex.internal.queue.SpscLinkedArrayQueue.lvElement(SpscLinkedArrayQueue.java:249)
 at io.reactivex.internal.queue.SpscLinkedArrayQueue.newBufferPoll(SpscLinkedArrayQueue.java:154)
 at io.reactivex.internal.queue.SpscLinkedArrayQueue.poll(SpscLinkedArrayQueue.java:144)
 at io.reactivex.internal.queue.SpscLinkedArrayQueue.clear(SpscLinkedArrayQueue.java:184)
 at io.reactivex.internal.operators.mixed.ObservableConcatMapMaybe$ConcatMapMaybeMainObserver.dispose(ObservableConcatMapMaybe.java:152)
 at io.reactivex.internal.observers.BasicFuseableObserver.dispose(BasicFuseableObserver.java:152)
 at io.reactivex.internal.observers.BasicFuseableObserver.dispose(BasicFuseableObserver.java:152)
 at io.reactivex.internal.operators.observable.ObservableTake$TakeObserver.dispose(ObservableTake.java:90)
 at io.reactivex.internal.disposables.DisposableHelper.dispose(DisposableHelper.java:125)
 at io.reactivex.internal.observers.LambdaObserver.dispose(LambdaObserver.java:100)
 at java.util.HashMap$Values.forEach(HashMap.java:981)

java.lang.NullPointerException
 at io.reactivex.internal.queue.SpscLinkedArrayQueue.lvElement(SpscLinkedArrayQueue.java:249)
 at io.reactivex.internal.queue.SpscLinkedArrayQueue.newBufferPoll(SpscLinkedArrayQueue.java:154)
 at io.reactivex.internal.queue.SpscLinkedArrayQueue.poll(SpscLinkedArrayQueue.java:144)
 at io.reactivex.internal.queue.SpscLinkedArrayQueue.clear(SpscLinkedArrayQueue.java:184)
 at io.reactivex.internal.operators.mixed.ObservableConcatMapMaybe$ConcatMapMaybeMainObserver.drain(ObservableConcatMapMaybe.java:200)
 at io.reactivex.internal.operators.mixed.ObservableConcatMapMaybe$ConcatMapMaybeMainObserver.innerSuccess(ObservableConcatMapMaybe.java:165)
 at io.reactivex.internal.operators.mixed.ObservableConcatMapMaybe$ConcatMapMaybeMainObserver$ConcatMapMaybeObserver.onSuccess(ObservableConcatMapMaybe.java:290)
 at io.reactivex.internal.operators.single.SingleFlatMapMaybe$FlatMapMaybeObserver.onSuccess(SingleFlatMapMaybe.java:117)
 at io.reactivex.internal.operators.maybe.MaybeJust.subscribeActual(MaybeJust.java:36)
 at io.reactivex.Maybe.subscribe(Maybe.java:4065)

This didn’t happen on 2.1.10 or any of the previous versions. Please tell me if I can help more.

[DavidDTA]

For the record, using hide() did stop the crashes.

[akarnokd]

You are welcome. Still, please keep using 2.1.11 as long as 2.1.12 comes out in case there are more mistakes such as this - you seem to be exceptionally lucky to stumble upon them as it takes about 1 minute on my desktop machine to trigger the bug by only using standard methods.