Editor Crashes when spawning a Physics enabled object inside another.

Regression: Unknown

Can Test in Main if requested.

Steps to Reproduce

(This was the best 100% repro that I was able to find. Sorry for the length! I have attached 2 images that show the expected setup)

  1. Open UE4 Editor
  2. Create a new FirstPerson blueprint project
  3. Right-click in the Context Browser and create a new blueprint Actor
  4. Name it 'Actor_01' and double-click to open it into the blueprint editor
  5. Click the Add Component button in the components menu, select to add a Cube
  6. In the components menu, drag the Cube onto the DefaultSceneRoot to set it as the new SceneRoot
  7. With the Cube selected
    1. In the Details menu, under Transform, set the X, Y, Z Scales to 1.2
    2. In the Details menu, under Physics, Enable Simulate Physics
  8. In the Components menu, Duplicate the Cube, Select it and press Ctrl+C then Ctrl+V
  9. Focus the Event Graph
  10. Right-click the graph and create a Custom Event node, name it Spawn
  11. Drag from the output pin and create a 'Spawn Actor from Class' node
  12. Within the node set the Class to Actor_01
  13. Click and Drag the Cube from the Context menu to the graph to create a Reference node
  14. Drag from the output pin of the reference and place a Get Relative Transform node
  15. Connect the Transform node to the 'Spawn Transform' input pin on the Spawn Actor node
  16. Return to the Editor Viewport and find then open FirstPersonProjectile in the Context Browser
  17. Focus the Event Graph then find the Event Hit node
  18. Use Alt+Left-click on the node's output pins to break their connections
  19. Drag from the Event Hit output pin and create a Cast to Actor_01 node
  20. Connect the 'Cast to actor_01' Object input pin to the 'Event Hit' Other output pin
  21. Drag from the As Actor 01 output pin and create a Spawn call function
  22. In the Editor Viewport, drag an instance of Actor_01 into the level then PIE
  23. Shoot the Actor_01 cube multiple times

Editor Crashes

UE4Editor_Engine!FPhysScene::SyncComponentsToBodies_AssumesLocked() physscene.cpp:1255 
UE4Editor_Engine!FPhysScene::EndFrame() physscene.cpp:1563 
UE4Editor_Engine!TBaseUObjectMethodDelegateInstance<0,UWorld,void __cdecl() delegateinstancesimpl.h:858 
UE4Editor_Engine!TGraphTask<FSimpleDelegateGraphTask>::ExecuteTask() taskgraphinterfaces.h:784 
UE4Editor_Core!FNamedTaskThread::ProcessTasksNamedThread() taskgraph.cpp:651 
UE4Editor_Core!FNamedTaskThread::ProcessTasksUntilQuit() taskgraph.cpp:560 
UE4Editor_Core!FTaskGraphImplementation::WaitUntilTasksComplete() taskgraph.cpp:1330 
UE4Editor_Engine!FTickTaskSequencer::ReleaseTickGroup() ticktaskmanager.cpp:542 
UE4Editor_Engine!FTickTaskManager::RunTickGroup() ticktaskmanager.cpp:1454 
UE4Editor_Engine!UWorld::RunTickGroup() leveltick.cpp:760 
UE4Editor_Engine!UWorld::Tick() leveltick.cpp:1426 
UE4Editor_UnrealEd!UEditorEngine::Tick() editorengine.cpp:1659 
UE4Editor_UnrealEd!UUnrealEdEngine::Tick() unrealedengine.cpp:396 
UE4Editor!FEngineLoop::Tick() launchengineloop.cpp:3295 
UE4Editor!GuardedMain() launch.cpp:166 
UE4Editor!GuardedMainWrapper() launchwindows.cpp:134 
UE4Editor!WinMain() launchwindows.cpp:210 
UE4Editor!__scrt_common_main_seh() exe_common.inl:253 

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ComponentUE - Simulation - Physics
Affects Versions4.18
Target Fix4.18
Fix Commit3661751
Release Commit3661751
CreatedSep 22, 2017
ResolvedSep 25, 2017
UpdatedApr 27, 2018