Unreal Engine Issues and Bug Tracker (UE-184193)

Description

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

Create a new First Person Template project
Enable the Gameplay State Tree and State Tree plugins then restart the editor
Right click in the Content Browser then select Artificial Intelligence > State Tree > State Tree Component name the State Tree "ST_Test"
Open the new State Tree Component
Expand the Common > Schema section
Set the Context Actor Class to BP_FirstPersonCharacter then compile
Right click the blue Root state then select Add Child State naming it "Test" then compile
Select the Test state then add an element to Transitions in the Details panel
Expand the Go to State Test section
Set Trigger to On Tick
Set Transition to Root
Add an element to the Conditions then set it to Bool Compare
To the right of Left IN select Bind > Actor > Has Rifle
Set Right to True
Compile, save, and close the State Tree
Open the BP_FirstPersonCharacter
Add a State Tree component to the Components hierarchy
Select the new component then set the State Tree to ST_Test
Compile, save, and close the Blueprint
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

Callstack

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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Fixed

Component	UE - AI - StateTree
Affects Versions	5.2
Target Fix	5.3

Fix Commit	26143160
Main Commit	26148754
Release Commit	26148894

Created	Apr 25, 2023
Resolved	Jun 21, 2023
Updated	Jul 26, 2023