Game crashes when loading certain maps

I’m getting the following crash dump any time I try to load certain maps of mine. I can edit my menu map or even launch the game into the menu, but any time I try to edit the map, or click a button in the game that would launch said map, it crashes. I get the following dump:

LoginId:104c0bb44be56b8d67215abaab533fdf
EpicAccountId:8d87a8ed92f141fd9e110100c5275e3e

Assertion failed: NULL != GeneratedClass [File:D:\Build\++UE4+Release-4.15+Compile\Sync\Engine\Source\Runtime\Engine\Private\Blueprint.cpp] [Line: 631] 



UE4Editor_Core!FDebug::AssertFailed() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\core\private\misc\assertionmacros.cpp:349]
UE4Editor_Engine!UBlueprint::PostLoad() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\engine\private\blueprint.cpp:632]
UE4Editor_CoreUObject!UObject::ConditionalPostLoad() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\coreuobject\private\uobject\obj.cpp:859]
UE4Editor_CoreUObject!EndLoad() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\coreuobject\private\uobject\uobjectglobals.cpp:1635]
UE4Editor_CoreUObject!LoadPackageInternalInner() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\coreuobject\private\uobject\uobjectglobals.cpp:1321]
UE4Editor_CoreUObject!LoadPackage() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\coreuobject\private\uobject\uobjectglobals.cpp:1477]
UE4Editor_CoreUObject!ResolveName() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\coreuobject\private\uobject\uobjectglobals.cpp:756]
UE4Editor_CoreUObject!StaticLoadObjectInternal() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\coreuobject\private\uobject\uobjectglobals.cpp:843]
UE4Editor_CoreUObject!StaticLoadObject() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\coreuobject\private\uobject\uobjectglobals.cpp:903]
UE4Editor_ContentBrowser!FAssetData::GetAsset() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\assetregistry\public\assetdata.h:232]
UE4Editor_ContentBrowser!SContentBrowser::OnAssetsActivated() [d:\build\++ue4+release-4.15+compile\sync\engine\source\editor\contentbrowser\private\scontentbrowser.cpp:1848]
UE4Editor_ContentBrowser!TBaseSPMethodDelegateInstance<0,SContentBrowser,0,TTypeWrapper<void> __cdecl(TArray<FAssetData,FDefaultAllocator> const & __ptr64,enum EAssetTypeActivationMethod::Type)>::Execute() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:327]
UE4Editor_ContentBrowser!TBaseSPMethodDelegateInstance<0,SContentBrowser,0,void __cdecl(TArray<FAssetData,FDefaultAllocator> const & __ptr64,enum EAssetTypeActivationMethod::Type)>::ExecuteIfSafe() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:434]
UE4Editor_ContentBrowser!TBaseDelegate<void,TArray<FAssetData,FDefaultAllocator> const & __ptr64,enum EAssetTypeActivationMethod::Type>::ExecuteIfBound() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\core\public\delegates\delegatesignatureimpl.inl:624]
UE4Editor_ContentBrowser!SAssetView::OnListMouseButtonDoubleClick() [d:\build\++ue4+release-4.15+compile\sync\engine\source\editor\contentbrowser\private\sassetview.cpp:3693]
UE4Editor_ContentBrowser!TBaseSPMethodDelegateInstance<0,SAssetView,0,TTypeWrapper<void> __cdecl(TSharedPtr<FAssetViewItem,0>)>::Execute() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:327]
UE4Editor_ContentBrowser!TBaseSPMethodDelegateInstance<0,SAssetView,0,void __cdecl(TSharedPtr<FAssetViewItem,0>)>::ExecuteIfSafe() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:434]
UE4Editor_ContentBrowser!TBaseDelegate<void,TSharedPtr<FAssetViewItem,0> >::ExecuteIfBound() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\core\public\delegates\delegatesignatureimpl.inl:624]
UE4Editor_ContentBrowser!SListView<TSharedPtr<FAssetViewItem,0> >::Private_OnItemDoubleClicked() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\slate\public\widgets\views\slistview.h:800]
UE4Editor_ContentBrowser!STableRow<TSharedPtr<FAssetViewItem,0> >::OnMouseButtonDoubleClick() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\slate\public\widgets\views\stablerow.h:287]
UE4Editor_Slate!<lambda_eeb33fd1b480e3cad58a1531d90d2e14>::operator()() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5473]
UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FBubblePolicy,FPointerEvent,<lambda_eeb33fd1b480e3cad58a1531d90d2e14> >() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:238]
UE4Editor_Slate!FSlateApplication::RoutePointerDoubleClickEvent() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5471]
UE4Editor_Slate!FSlateApplication::ProcessMouseButtonDoubleClickEvent() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5454]
UE4Editor_Slate!FSlateApplication::OnMouseDoubleClick() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5432]
UE4Editor_Core!FWindowsApplication::ProcessDeferredMessage() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:1702]
UE4Editor_Core!FWindowsApplication::DeferMessage() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:2120]
UE4Editor_Core!FWindowsApplication::ProcessMessage() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:867]
UE4Editor_Core!FWindowsApplication::AppWndProc() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:714]
user32
user32
UE4Editor_Core!FWindowsPlatformMisc::PumpMessages() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\core\private\windows\windowsplatformmisc.cpp:980]
UE4Editor!FEngineLoop::Tick() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\launch\private\launchengineloop.cpp:2977]
UE4Editor!GuardedMain() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\launch\private\launch.cpp:166]
UE4Editor!GuardedMainWrapper() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:134]
UE4Editor!WinMain() [d:\build\++ue4+release-4.15+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:210]
UE4Editor!__scrt_common_main_seh() [f:\dd\vctools\crt\vcstartup\src\startup\exe_common.inl:264]
kernel32
ntdll

I can’t seem to make any sense of it. Given that it’s only with certain maps I’m guessing a specific Blueprint is to blame, but I have no idea on how to begin troubleshooting which it is. I’m using a purely Blueprint based game, no custom C++ code.

Any help would be appreciated.

Hi OKomili,

Looking at your crash reporter data, the crash is occurring on line 631 below:

626       if( FBlueprintEditorUtils::SupportsConstructionScript(this) )
  627       {
  628       if(SimpleConstructionScript == NULL)
  629       {
  630       check(NULL != GeneratedClass);
  631 ***** SimpleConstructionScript = NewObject<USimpleConstructionScript>(GeneratedClass);
  632       SimpleConstructionScript->SetFlags(RF_Transactional);
  633       
  634       UBlueprintGeneratedClass* BPGClass = Cast<UBlueprintGeneratedClass>(*GeneratedClass);
  635       if(BPGClass)
  636       {
  637       BPGClass->SimpleConstructionScript = SimpleConstructionScript;

This crash is reported among very few users so is likely a problem in a Construction Script and not a bug with the engine. While there is not enough data to pinpoint the exact cause of the crash, hopefully this will help you narrow down where the problem is originating.

.

Hi ,

I decided to rollback my changes to the most recent commit (using git) and everything started working again, but never managed to pinpoint the exact issue triggering the crash. Sadly I don’t remember what exactly I changed from said commit, so it’s probably just a matter of time before I re implement the changes. Hopefully I can track down the issue or avoid it altogether next time :slight_smile:

Thanks,

Onur