Description

REGRESSION: Issue does not occur in 4.24

Crash occurs when the user changes a blueprint TMap value from Vector to Vector4 and then compiles the blueprint.

This seems to only occur with TMaps, as I wasn't able to reproduce this with other container types. I also wasn't able to reproduce this by changing the Vector to an Int, or from Int to Vector4.

Steps to Reproduce
  1. Download and extract the attached project.
  2. Open the project in editor.
  3. Open TestBP.
  4. Select the variable TestMap.
  5. Change the Value from Vector to Vector4
  6. Compile.

RESULT

Crash

Callstack
Assertion failed: Tag.Size == Loaded [File:D:/Build/++UE4+Licensee/Sync/Engine/Source/Runtime/CoreUObject/Private/UObject/Class.cpp] [Line: 1478] 

KERNELBASE.dll!UnknownFunction []
UE4Editor-Core.dll!ReportAssert() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Core\Private\Windows\WindowsPlatformCrashContext.cpp:1541]
UE4Editor-Core.dll!FWindowsErrorOutputDevice::Serialize() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Core\Private\Windows\WindowsErrorOutputDevice.cpp:78]
UE4Editor-Core.dll!FOutputDevice::LogfImpl() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Core\Private\Misc\OutputDevice.cpp:61]
UE4Editor-Core.dll!AssertFailedImplV() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Core\Private\Misc\AssertionMacros.cpp:100]
UE4Editor-Core.dll!FDebug::CheckVerifyFailedImpl() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Core\Private\Misc\AssertionMacros.cpp:450]
UE4Editor-CoreUObject.dll!UStruct::SerializeVersionedTaggedProperties() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\Class.cpp:1478]
UE4Editor-CoreUObject.dll!UStruct::SerializeTaggedProperties() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\Class.cpp:1266]
UE4Editor-CoreUObject.dll!UObject::SerializeScriptProperties() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\Obj.cpp:1438]
UE4Editor-CoreUObject.dll!UObject::Serialize() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\Obj.cpp:1358]
UE4Editor-CoreUObject.dll!UObject::Serialize() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\Obj.cpp:1247]
UE4Editor-Engine.dll!AActor::Serialize() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Engine\Private\Actor.cpp:665]
UE4Editor-Engine.dll!UEngine::CopyPropertiesForUnrelatedObjects() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Engine\Private\UnrealEngine.cpp:14329]
UE4Editor-UnrealEd.dll!FBlueprintCompileReinstancer::CopyPropertiesForUnrelatedObjects() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Editor\UnrealEd\Private\Kismet2\KismetReinstanceUtilities.cpp:2387]
UE4Editor-Kismet.dll!FBlueprintCompilationManagerImpl::ReinstanceBatch() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Editor\Kismet\Private\BlueprintCompilationManager.cpp:2013]
UE4Editor-Kismet.dll!FBlueprintCompilationManagerImpl::FlushCompilationQueueImpl() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Editor\Kismet\Private\BlueprintCompilationManager.cpp:1362]
UE4Editor-Kismet.dll!FBlueprintCompilationManagerImpl::CompileSynchronouslyImpl() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Editor\Kismet\Private\BlueprintCompilationManager.cpp:263]
UE4Editor-Kismet.dll!FBlueprintCompilationManager::CompileSynchronously() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Editor\Kismet\Private\BlueprintCompilationManager.cpp:3040]
UE4Editor-UnrealEd.dll!FKismetEditorUtilities::CompileBlueprint() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Editor\UnrealEd\Private\Kismet2\Kismet2.cpp:754]
UE4Editor-Kismet.dll!FBlueprintEditor::Compile() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Editor\Kismet\Private\BlueprintEditor.cpp:3474]
UE4Editor-Kismet.dll!TBaseSPMethodDelegateInstance<0,FBlueprintEditor,0,void __cdecl(void)>::ExecuteIfSafe() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:374]
UE4Editor-Slate.dll!FUICommandList::ExecuteAction() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Slate\Private\Framework\Commands\UICommandList.cpp:102]
UE4Editor-Slate.dll!SToolBarButtonBlock::OnClicked() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Slate\Private\Framework\MultiBox\SToolBarButtonBlock.cpp:302]
UE4Editor-Slate.dll!TBaseSPMethodDelegateInstance<0,SToolBarButtonBlock,0,FReply __cdecl(void)>::Execute() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:298]
UE4Editor-Slate.dll!SButton::ExecuteOnClick() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Slate\Private\Widgets\Input\SButton.cpp:385]
UE4Editor-Slate.dll!SButton::OnMouseButtonUp() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Slate\Private\Widgets\Input\SButton.cpp:304]
UE4Editor-Slate.dll!FEventRouter::Route<FReply,FEventRouter::FToLeafmostPolicy,FPointerEvent,<lambda_cc5aea9e7377b04ce85c30c65ec3889b> >() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:372]
UE4Editor-Slate.dll!FSlateApplication::RoutePointerUpEvent() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:4675]
UE4Editor-Slate.dll!FSlateApplication::ProcessMouseButtonUpEvent() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:5198]
UE4Editor-Slate.dll!FSlateApplication::OnMouseUp() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:5166]
UE4Editor-ApplicationCore.dll!FWindowsApplication::ProcessDeferredMessage() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:2133]
UE4Editor-ApplicationCore.dll!FWindowsApplication::DeferMessage() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:2585]
UE4Editor-ApplicationCore.dll!FWindowsApplication::ProcessMessage() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:1809]
UE4Editor-ApplicationCore.dll!FWindowsApplication::AppWndProc() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:852]
USER32.dll!UnknownFunction []
USER32.dll!UnknownFunction []
UE4Editor-ApplicationCore.dll!FWindowsPlatformApplicationMisc::PumpMessages() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsPlatformApplicationMisc.cpp:130]
UE4Editor.exe!FEngineLoop::Tick() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Launch\Private\LaunchEngineLoop.cpp:4762]
UE4Editor.exe!GuardedMain() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Launch\Private\Launch.cpp:169]
UE4Editor.exe!GuardedMainWrapper() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:137]
UE4Editor.exe!WinMain() [D:\Build\++UE4+Licensee\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:268]
UE4Editor.exe!__scrt_common_main_seh() [d:\agent\_work\5\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288]
KERNEL32.DLL!UnknownFunction []
ntdll.dll!UnknownFunction []

Have Comments or More Details?

There's no existing public thread on this issue, so head over toAnswerHub just mention UE-94970 in the post.

7
Login to Vote

Unresolved
ComponentCore - UObject
Affects Versions4.254.26
Target Fix4.26
CreatedJun 29, 2020
UpdatedJul 30, 2020