Crash when launching game immediately after closing with Application.Quit

We are seeing a constant and easy to reproduce crash with our game on Android (using Unity 4.5.4).

The scenario is easily reproduced by the following steps:

1. Quit game - this calls Application.Quit()
2. Immediately launch the game again from the launcher icon.

The cause of the crash seems to be some low-level Unity code that probably does some cleanup and times out:

Code (CSharp):

1. 1-28 20:23:03.775: E/AndroidRuntime(4545): FATAL EXCEPTION: FinalizerWatchdogDaemon
2. 01-28 20:23:03.775: E/AndroidRuntime(4545): Process: com.moonactive.pengi, PID: 4545
3. 01-28 20:23:03.775: E/AndroidRuntime(4545): java.lang.Error: FATAL EXCEPTION [FinalizerWatchdogDaemon]
4. 01-28 20:23:03.775: E/AndroidRuntime(4545): Unity version     : 4.5.4f1
5. 01-28 20:23:03.775: E/AndroidRuntime(4545): Device model      : samsung SM-T700
6. 01-28 20:23:03.775: E/AndroidRuntime(4545): Device fingerprint: samsung/klimtwifixx/klimtwifi:4.4.2/KOT49H/T700XXU1ANF9:user/release-keys
7. 01-28 20:23:03.775: E/AndroidRuntime(4545): Caused by: java.util.concurrent.TimeoutException: com.unity3d.player.ReflectionHelper$1.finalize() timed out after 10 seconds
8. 01-28 20:23:03.775: E/AndroidRuntime(4545):     at com.unity3d.player.ReflectionHelper.nativeProxyFinalize(Native Method)
9. 01-28 20:23:03.775: E/AndroidRuntime(4545):     at com.unity3d.player.ReflectionHelper.a(Unknown Source)
10. 01-28 20:23:03.775: E/AndroidRuntime(4545):     at com.unity3d.player.ReflectionHelper$1.finalize(Unknown Source)
11. 01-28 20:23:03.775: E/AndroidRuntime(4545):     at java.lang.Daemons$FinalizerDaemon.doFinalize(Daemons.java:187)
12. 01-28 20:23:03.775: E/AndroidRuntime(4545):     at java.lang.Daemons$FinalizerDaemon.run(Daemons.java:170)
13. 01-28 20:23:03.775: E/AndroidRuntime(4545):     at java.lang.Thread.run(Thread.java:841)

My questions are:

1. Is using Application.Quit() safe? or should it be avoided ?
2. Is this a bug in Unity, or perhaps in our code (or some plugin code ?)
3. What can we use in the meantime (supposing Unity will not resolve this in the next 2 days )

 

Did you find solution for this?

 

This was reported as bug # 667260

I had a brief email communication with a dev from the Android team. @Yury Habets
Unfortunately, i did not receive any updates on this issue since i posted it.

As a workaround, we implemented this code:

Code (CSharp):

1. #if UNITY_ANDROID
2. AndroidUtil.Activity.Call<bool>("moveTaskToBack", true);
3. #else
4. Application.Quit ();
5. #endif

AndroidUtil.Activity is just a short notation for getting the main activity using AndroidJavaObject.

*Note that this does not quit the app, it merely moves the game to the background...

 

OK. Thanks.
I am not familiar with Unity bug tracking so where can I find that bug #667260? I didn't find it from IssueTracker NOR anything related to 'FATAL EXCEPTION: FinalizerWatchdogDaemon' either.

 

I have no idea either. Older bug reports are private maybe ? in any case, i did not receive any updates on that case...

 

@liortal Do you still use this trick with AndroidUtil instead of Application.Quit() ? I also see lots of crashes in Google Console with the similar stack trace in Unity 5.5.5p1.

 

No, we've since moved to a different project and a different Unity version (Unity 5.5.3p1 and later 2017.1.1).

I don't think we have that issue anymore, but i am not 100% sure.