Unreal Engine Issues and Bug Tracker (UE-173220)

Description

This is a Regression. Tested in //UE5/Release-5.0 CL 20979098 - "None" is not an option for the parent class and the "Reset this Property" is not initially there.

Steps to Reproduce

Create a new Blank Project
Open the Level BP
Click on Class Settings
In Details, under Class Options, click on the arrow right of the Parent Class option.
1. This will reset the Parent Class to "None"
Compile BP

Actual Result: Editor Crashes

Expected Result: The reset arrow should not appear for Parent Class at all

Callstack

Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x0000000000000038
UnrealEditor_KismetCompiler!FKismetCompilerContext::FinishCompilingClass() [D:\build\++UE5\Sync\Engine\Source\Editor\KismetCompiler\Private\KismetCompiler.cpp:2974]
UnrealEditor_KismetCompiler!FKismetCompilerContext::CompileFunctions() [D:\build\++UE5\Sync\Engine\Source\Editor\KismetCompiler\Private\KismetCompiler.cpp:4908]
UnrealEditor_Kismet!FBlueprintCompilationManagerImpl::FlushCompilationQueueImpl() [D:\build\++UE5\Sync\Engine\Source\Editor\Kismet\Private\BlueprintCompilationManager.cpp:1452]
UnrealEditor_Kismet!FBlueprintCompilationManagerImpl::CompileSynchronouslyImpl() [D:\build\++UE5\Sync\Engine\Source\Editor\Kismet\Private\BlueprintCompilationManager.cpp:269]
UnrealEditor_Kismet!FBlueprintCompilationManager::CompileSynchronously() [D:\build\++UE5\Sync\Engine\Source\Editor\Kismet\Private\BlueprintCompilationManager.cpp:3294]
UnrealEditor_UnrealEd!FKismetEditorUtilities::CompileBlueprint() [D:\build\++UE5\Sync\Engine\Source\Editor\UnrealEd\Private\Kismet2\Kismet2.cpp:763]
UnrealEditor_Kismet!FBlueprintEditor::Compile() [D:\build\++UE5\Sync\Engine\Source\Editor\Kismet\Private\BlueprintEditor.cpp:4060]
UnrealEditor_Kismet!TBaseSPMethodDelegateInstance<0,FBlueprintEditor,1,void __cdecl(void),FDefaultDelegateUserPolicy>::ExecuteIfSafe() [D:\build\++UE5\Sync\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:312]
UnrealEditor_Slate!FUICommandList::ExecuteAction() [D:\build\++UE5\Sync\Engine\Source\Runtime\Slate\Private\Framework\Commands\UICommandList.cpp:111]
UnrealEditor_Slate!SToolBarButtonBlock::OnClicked() [D:\build\++UE5\Sync\Engine\Source\Runtime\Slate\Private\Framework\MultiBox\SToolBarButtonBlock.cpp:384]
UnrealEditor_Slate!TBaseSPMethodDelegateInstance<0,SToolBarButtonBlock,1,FReply __cdecl(void),FDefaultDelegateUserPolicy>::Execute() [D:\build\++UE5\Sync\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:295]
UnrealEditor_Slate!SButton::ExecuteOnClick() [D:\build\++UE5\Sync\Engine\Source\Runtime\Slate\Private\Widgets\Input\SButton.cpp:465]
UnrealEditor_Slate!SButton::OnMouseButtonUp() [D:\build\++UE5\Sync\Engine\Source\Runtime\Slate\Private\Widgets\Input\SButton.cpp:390]
UnrealEditor_Slate!<lambda_51e270ca99ea7ce852539efd04dd453f>::operator()() [D:\build\++UE5\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:5046]
UnrealEditor_Slate!FEventRouter::Route<FReply,FEventRouter::FToLeafmostPolicy,FPointerEvent,<lambda_51e270ca99ea7ce852539efd04dd453f> >() [D:\build\++UE5\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:412]
UnrealEditor_Slate!FSlateApplication::RoutePointerUpEvent() [D:\build\++UE5\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:5032]
UnrealEditor_Slate!FSlateApplication::ProcessMouseButtonUpEvent() [D:\build\++UE5\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:5601]
UnrealEditor_Slate!FSlateApplication::OnMouseUp() [D:\build\++UE5\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:5566]
UnrealEditor_ApplicationCore!FWindowsApplication::ProcessDeferredMessage() [D:\build\++UE5\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:2219]
UnrealEditor_ApplicationCore!FWindowsApplication::DeferMessage() [D:\build\++UE5\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:2726]
UnrealEditor_ApplicationCore!FWindowsApplication::ProcessMessage() [D:\build\++UE5\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:1895]
UnrealEditor_ApplicationCore!FWindowsApplication::AppWndProc() [D:\build\++UE5\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:925]
user32
user32
InkObj
atlthunk
user32
user32
UnrealEditor_ApplicationCore!FWindowsPlatformApplicationMisc::PumpMessages() [D:\build\++UE5\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsPlatformApplicationMisc.cpp:142]
UnrealEditor!FEngineLoop::Tick() [D:\build\++UE5\Sync\Engine\Source\Runtime\Launch\Private\LaunchEngineLoop.cpp:5291]
UnrealEditor!GuardedMain() [D:\build\++UE5\Sync\Engine\Source\Runtime\Launch\Private\Launch.cpp:202]
UnrealEditor!GuardedMainWrapper() [D:\build\++UE5\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:107]
UnrealEditor!LaunchWindowsStartup() [D:\build\++UE5\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:244]
UnrealEditor!WinMain() [D:\build\++UE5\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:282]
UnrealEditor!__scrt_common_main_seh() [D:\a\_work\1\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288]
kernel32
ntdll

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Fixed

Component	UE - Gameplay - Blueprint Compiler
Affects Versions	5.1
Target Fix	5.2

Fix Commit	23676479
Main Commit	23676479

Created	Jan 3, 2023
Resolved	Jan 13, 2023
Updated	Apr 4, 2023

UE-173220

Level Blueprint can be reparented to None, crashes Editor on Compile

Level Blueprint can be reparented to None, crashes Editor on Compile

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