This is a regression. Tested in //UE5/Release-5.1 CL2390901

The crash occurred 3/5 times. Crash occurs while playing in editor with a State Tree using Bool Compare for a transition state to a child state.

Steps to Reproduce
  1. Create a new First Person Template project
  2. Enable the Gameplay State Tree and State Tree plugins then restart the editor
  3. Right click in the Content Browser then select Artificial Intelligence > State Tree > State Tree Component name the State Tree "ST_Test"
  4. Open the new State Tree Component
  5. Expand the Common > Schema section
  6. Set the Context Actor Class to BP_FirstPersonCharacter then compile
  7. Right click the blue Root state then select Add Child State naming it "Test" then compile
  8. Select the Test state then add an element to Transitions in the Details panel
  9. Expand the Go to State Test section
  10. Set Trigger to On Tick
  11. Set Transition to Root
  12. Add an element to the Conditions then set it to Bool Compare
  13. To the right of Left IN select Bind >  Actor > Has Rifle
  14. Set Right to True
  15. Compile, save, and close the State Tree
  16. Open the BP_FirstPersonCharacter
  17. Add a State Tree component to the Components hierarchy
  18. Select the new component then set the State Tree to ST_Test
  19. Compile, save, and close the Blueprint
  20. Play in Editor then attempt to pick up the Rifle

Expected Results:
Rifle is equipped and the state changes.

Actual Results:
Editor crashes with an assertion



Assertion failed: FieldSize != 0 [File:D:\build\++UE5\Sync\Engine\Source\Runtime\CoreUObject\Public\UObject\UnrealType.h] [Line: 2513]
UnrealEditor-StateTreeModule!7fff9f4e0000  + 2cd1c
UnrealEditor-StateTreeModule!7fff9f4e0000  + 1c1b9
UnrealEditor-StateTreeModule!7fff9f4e0000  + 3ecba
UnrealEditor-StateTreeModule!7fff9f4e0000  + 439f2
UnrealEditor-StateTreeModule!7fff9f4e0000  + 403ad
UnrealEditor-GameplayStateTreeModule!UStateTreeComponent::TickComponent(float,ELevelTick,FActorComponentTickFunction *) [StateTreeComponent.cpp:188]
UnrealEditor-Engine!static void FActorComponentTickFunction::ExecuteTickHelper<<lambda_f011d35eeb8a005f9c8ee1a0523134b3> >(class UActorComponent *, bool, float, ELevelTick, const class FActorComponentTickFunction::ExecuteTick::__l2::<lambda_f011d35eeb8a005f9c8ee1a0523134b3> & const) [Actor.h:4224]
UnrealEditor-Engine!FActorComponentTickFunction::ExecuteTick(float,ELevelTick,ENamedThreads::Type,TRefCountPtr<FGraphEvent> const &) [ActorComponent.cpp:1108]
UnrealEditor-Engine!FTickFunctionTask::DoTask(ENamedThreads::Type,TRefCountPtr<FGraphEvent> const &) [TickTaskManager.cpp:278]
UnrealEditor-Engine!TGraphTask<FTickFunctionTask>::ExecuteTask(TArray<FBaseGraphTask *,TSizedDefaultAllocator<32> > &,ENamedThreads::Type,bool) [TaskGraphInterfaces.h:1310]
UnrealEditor-Core!FNamedTaskThread::ProcessTasksNamedThread(int,bool) [TaskGraph.cpp:758]
UnrealEditor-Core!FNamedTaskThread::ProcessTasksUntilIdle(int) [TaskGraph.cpp:660]
UnrealEditor-Engine!FTickTaskSequencer::ReleaseTickGroup(ETickingGroup,bool) [TickTaskManager.cpp:573]
UnrealEditor-Engine!FTickTaskManager::RunTickGroup(ETickingGroup,bool) [TickTaskManager.cpp:1583]
UnrealEditor-Engine!UWorld::RunTickGroup(ETickingGroup,bool) [LevelTick.cpp:770]
UnrealEditor-Engine!UWorld::Tick(ELevelTick,float) [LevelTick.cpp:1527]
UnrealEditor-UnrealEd!7fffb8520000  + 71aadf
UnrealEditor-UnrealEd!7fffb8520000  + 11ad2c6
UnrealEditor!7ff711ea0000  + 88f8
UnrealEditor!7ff711ea0000  + 24fcc
UnrealEditor!7ff711ea0000  + 250ba
UnrealEditor!7ff711ea0000  + 27df0
UnrealEditor!7ff711ea0000  + 3afd4
UnrealEditor!7ff711ea0000  + 3e4e6
KERNEL32!7ff85eef0000  + 17604
ntdll!7ff85eff0000  + 526a1



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ComponentUE - AI - StateTree
Affects Versions5.2
Target Fix5.3
Fix Commit26143160
Main Commit26148754
Release Commit26148894
CreatedApr 25, 2023
ResolvedJun 21, 2023
UpdatedJul 26, 2023