Editor keeps crashing on start all of a sudden with Assertion failed on expression: '!gameObject.IsA

Hello all,
My game keeps crashing whenever I hit play. I have been messing with everything I can think of and I can't find anything wrong. All was fine, then on time I hit play (I was only messing around with the positioning of things at the time) and this started, and it happens every time now.

Code (CSharp):

1. 0x00000001408C64F1 (Unity) FindActiveTransformWithPathImpl
2. 0x00000001408C4C80 (Unity) FindActiveTransformWithPath
3. 0x000000014142B906 (Unity) GameObject_CUSTOM_Find
4. 0x00000000C72796A5 (Mono JIT Code) (wrapper managed-to-native) UnityEngine.GameObject:Find (string)
5. 0x00000000C7279548 (Mono JIT Code) [C:\buildslave\unity\build\Extensions\TestRunner\UnityEngine.TestRunner\TestRunner\PlaymodeTestsController.cs:48] UnityEngine.TestTools.TestRunner.PlaymodeTestsController:IsControllerOnScene ()
6. 0x00000000C7279106 (Mono JIT Code) [C:\buildslave\unity\build\Extensions\TestRunner\UnityEditor.TestRunner\TestLaunchers\PlaymodeLauncher.cs:98] UnityEditor.TestTools.TestRunner.PlaymodeLauncher/BackgroundWatcher:OnPlayModeStateChanged (UnityEditor.PlayModeStateChange)
7. 0x00000000C7278AC4 (Mono JIT Code) (wrapper delegate-invoke) System.Action`1<UnityEditor.PlayModeStateChange>:invoke_void__this___PlayModeStateChange (UnityEditor.PlayModeStateChange)
8. 0x00000000C7278AC4 (Mono JIT Code) (wrapper delegate-invoke) System.Action`1<UnityEditor.PlayModeStateChange>:invoke_void__this___PlayModeStateChange (UnityEditor.PlayModeStateChange)
9. 0x00000000C7278AC4 (Mono JIT Code) (wrapper delegate-invoke) System.Action`1<UnityEditor.PlayModeStateChange>:invoke_void__this___PlayModeStateChange (UnityEditor.PlayModeStateChange)
10. 0x00000000C7278AC4 (Mono JIT Code) (wrapper delegate-invoke) System.Action`1<UnityEditor.PlayModeStateChange>:invoke_void__this___PlayModeStateChange (UnityEditor.PlayModeStateChange)

 

I'm having this exact same issue and have been struggling to find the cause/solution. If I wipe my temp and library directories and let everything import/rebuild it usually works again (but not 100% of the time), or if I roll back to an earlier commit in my git repo then reapply my changes it sometimes works again (again, not 100% of the time). When I do get it working again, it's only a short while before the problem pops back up for me.

Code (CSharp):

1.  
2. 0x00000001403BFA26 (Unity) GameObject::IsActive
3. 0x00000001408C68E6 (Unity) FindActiveTransformWithPathImpl
4. 0x00000001408C5100 (Unity) FindActiveTransformWithPath
5. 0x000000014142CDA6 (Unity) GameObject_CUSTOM_Find
6. 0x000000004B8DB7EE (Mono JIT Code) (wrapper managed-to-native) UnityEngine.GameObject:Find (string)
7. 0x000000004B8DB66F (Mono JIT Code) [C:\buildslave\unity\build\Extensions\TestRunner\UnityEngine.TestRunner\TestRunner\PlaymodeTestsController.cs:48] UnityEngine.TestTools.TestRunner.PlaymodeTestsController:IsControllerOnScene ()
8. 0x000000004B8DB1F6 (Mono JIT Code) [C:\buildslave\unity\build\Extensions\TestRunner\UnityEditor.TestRunner\TestLaunchers\PlaymodeLauncher.cs:98] UnityEditor.TestTools.TestRunner.PlaymodeLauncher/BackgroundWatcher:OnPlayModeStateChanged (UnityEditor.PlayModeStateChange)
9. 0x000000004B8DB0A2 (Mono JIT Code) (wrapper delegate-invoke) System.Action`1<UnityEditor.PlayModeStateChange>:invoke_void_T (UnityEditor.PlayModeStateChange)
10. 0x000000004B8DA884 (Mono JIT Code) [C:\buildslave\unity\build\Editor\Mono\EditorApplication.cs:219] UnityEditor.EditorApplication:Internal_PlayModeStateChanged (UnityEditor.PlayModeStateChange)
11. 0x000000004AB2016A (Mono JIT Code) (wrapper runtime-invoke) <Module>:runtime_invoke_void_int (object,intptr,intptr,intptr)
12. 0x00007FFA4D41436A (mono-2.0-bdwgc) [c:\buildslave\mono\build\mono\mini\mini-runtime.c:2620] mono_jit_runtime_invoke
13. 0x00007FFA4D619567 (mono-2.0-bdwgc) [c:\buildslave\mono\build\mono\metadata\object.c:2853] do_runtime_invoke
14. 0x00007FFA4D621F6F (mono-2.0-bdwgc) [c:\buildslave\mono\build\mono\metadata\object.c:2905] mono_runtime_invoke
15. 0x00000001407ECDC9 (Unity) mono_runtime_invoke_profiled
16. 0x0000000140A22A2E (Unity) CallStaticMonoMethod
17. 0x0000000140A22B3F (Unity) CallStaticMonoMethod
18. 0x0000000140A23BB1 (Unity) CallStaticMonoMethod
19. 0x00000001411DF0D6 (Unity) PlayerLoopController::SetIsPlayingDelayed
20. 0x000000004B8DA61E (Mono JIT Code) (wrapper managed-to-native) UnityEditor.EditorApplication:set_isPlaying (bool)
21. 0x000000004B8DA4D7 (Mono JIT Code) [C:\buildslave\unity\build\Editor\Mono\GUI\Toolbar.cs:719] UnityEditor.Toolbar:TogglePlaying ()
22. 0x000000004ACF0729 (Mono JIT Code) [C:\buildslave\unity\build\Editor\Mono\GUI\Toolbar.cs:523] UnityEditor.Toolbar:DoPlayButtons (bool)
23. 0x000000004ACE53AC (Mono JIT Code) [C:\buildslave\unity\build\Editor\Mono\GUI\Toolbar.cs:367] UnityEditor.Toolbar:OldOnGUI ()
24. 0x000000004AB03689 (Mono JIT Code) [C:\buildslave\unity\build\Runtime\UIElements\Managed\IMGUIContainer.cs:182] UnityEngine.Experimental.UIElements.IMGUIContainer:DoOnGUI (UnityEngine.Event)
25. 0x000000004AB02389 (Mono JIT Code) [C:\buildslave\unity\build\Runtime\UIElements\Managed\IMGUIContainer.cs:340] UnityEngine.Experimental.UIElements.IMGUIContainer:HandleIMGUIEvent (UnityEngine.Event)
26. 0x000000003FFB1F2F (Mono JIT Code) [C:\buildslave\unity\build\Runtime\UIElements\Managed\IMGUIContainer.cs:322] UnityEngine.Experimental.UIElements.IMGUIContainer:HandleEvent (UnityEngine.Experimental.UIElements.EventBase)
27. 0x000000003FFA4CAC (Mono JIT Code) [C:\buildslave\unity\build\Runtime\UIElements\Managed\EventDispatcher.cs:251] UnityEngine.Experimental.UIElements.EventDispatcher:DispatchEvent (UnityEngine.Experimental.UIElements.EventBase,UnityEngine.Experimental.UIElements.IPanel)
28. 0x000000004AACA124 (Mono JIT Code) [C:\buildslave\unity\build\Runtime\UIElements\Managed\UIElementsUtility.cs:252] UnityEngine.Experimental.UIElements.UIElementsUtility:DoDispatch (UnityEngine.Experimental.UIElements.BaseVisualElementPanel)
29. 0x000000004AAC8E67 (Mono JIT Code) [C:\buildslave\unity\build\Runtime\UIElements\Managed\UIElementsUtility.cs:78] UnityEngine.Experimental.UIElements.UIElementsUtility:ProcessEvent (int,intptr)
30. 0x000000004AAC7CD4 (Mono JIT Code) [C:\buildslave\unity\build\Runtime\IMGUI\Managed\GUIUtility.cs:175] UnityEngine.GUIUtility:ProcessEvent (int,intptr)
31. 0x000000004AAC7FFF (Mono JIT Code) (wrapper runtime-invoke) <Module>:runtime_invoke_bool_int_intptr (object,intptr,intptr,intptr)
32. 0x00007FFA4D41436A (mono-2.0-bdwgc) [c:\buildslave\mono\build\mono\mini\mini-runtime.c:2620] mono_jit_runtime_invoke
33. 0x00007FFA4D619567 (mono-2.0-bdwgc) [c:\buildslave\mono\build\mono\metadata\object.c:2853] do_runtime_invoke
34. 0x00007FFA4D621F6F (mono-2.0-bdwgc) [c:\buildslave\mono\build\mono\metadata\object.c:2905] mono_runtime_invoke
35. 0x0000000140A2EF6C (Unity) scripting_method_invoke
36. 0x0000000140A229AA (Unity) ScriptingInvocation::Invoke
37. 0x0000000140A23A5A (Unity) ScriptingInvocation::Invoke<bool>
38. 0x0000000140282DAE (Unity) IMGUIScriptingClasses::ProcessEvent
39. 0x000000014112A4AF (Unity) GUIView::ProcessRetainedMode
40. 0x00000001413FAA88 (Unity) GUIView::OnInputEvent
41. 0x000000014112A34C (Unity) GUIView::ProcessInputEvent
42. 0x00000001413F2A55 (Unity) GUIView::ProcessEventMessages
43. 0x00000001413FCA4A (Unity) GUIView::GUIViewWndProc
44. 0x00007FFA7FC3BC50 (USER32) CallWindowProcW
45. 0x00007FFA7FC3B5CF (USER32) DispatchMessageW
46. 0x000000014140FE90 (Unity) MainMessageLoop
47. 0x00000001414117AC (Unity) WinMain
48. 0x0000000141E65728 (Unity) __tmainCRTStartup
49. 0x00007FFA80522774 (KERNEL32) BaseThreadInitThunk
50. 0x00007FFA81E50D51 (ntdll) RtlUserThreadStart
51.  

Using Unity version 2017.3.1f1

 

Mine ended up being a corrupted scene file. I took everything in my scene saved it all as prefabs in a folder, made a new scene, put it all back in, and everything was fine, not only that, it felt like it was running twice as good.

 

That's interesting. I get the issue with any scene once it starts happening. I'd be inclined to think it's an issue with one of my prefabs, but it's strange that the issue goes away temporarily when i roll-back/re-apply some git commits and then just comes back after a while - usually a few days later.

Hopefully your issue doesn't creep back like mine does.

I'm in the 'broken' state right now so I've been slowly walking through all my scripts setting breakpoints, etc to try narrowing down where the crash happens.

 

Oh the joys of game dev... lol. Good luck man.