This is a common crash affecting users in 4.16. Additional information is not currently available.
User Descriptions
Source Context
787 // NOTE: The following is an Unreal extension to standard shared_ptr behavior 788 FORCEINLINE TSharedRef< ObjectType, Mode > ToSharedRef() const 789 { 790 // If this assert goes off, it means a shared reference was created from a shared pointer that was nullptr. 791 // Shared references are never allowed to be null. Consider using TSharedPtr instead. 792 check( IsValid() ); 793 ***** return TSharedRef< ObjectType, Mode >( *this ); 794 }
Happened while painting with sculpt selected and painting close to the Target Layer list, sometime dragging from the Target Layer list.
Assertion failed: IsValid() [File:D:\Build\++UE4+Release-4.16+Compile\Sync\Engine\Source\Runtime\Core\Public\Templates/SharedPointer.h] [Line: 793] UE4Editor_LandscapeEditor!TSharedPtr<SWidget,0>::ToSharedRef() [sharedpointer.h:794] UE4Editor_LandscapeEditor!FTargetLayerDragDropOp::GetDefaultDecorator() [landscapeeditordetailcustomization_targetlayers.cpp:1497] UE4Editor_SlateCore!FDragDropOperation::CreateCursorDecoratorWindow() [draganddrop.cpp:104] UE4Editor_LandscapeEditor!FTargetLayerDragDropOp::New() [landscapeeditordetailcustomization_targetlayers.cpp:1486] UE4Editor_LandscapeEditor!FLandscapeEditorCustomNodeBuilder_TargetLayers::HandleDragDetected() [landscapeeditordetailcustomization_targetlayers.cpp:777] UE4Editor_LandscapeEditor!TMemberFunctionCaller<FLandscapeEditorCustomNodeBuilder_TargetLayers,FReply() [delegateinstanceinterface.h:165] UE4Editor_LandscapeEditor!UE4Tuple_Private::TTupleImpl<TIntegerSequence<unsigned int> >::ApplyAfter<TMemberFunctionCaller<FLandscapeEditorCustomNodeBuilder_TargetLayers,FReply() [tuple.h:497] UE4Editor_LandscapeEditor!TBaseSPMethodDelegateInstance<0,FLandscapeEditorCustomNodeBuilder_TargetLayers,0,FReply __cdecl() [delegateinstancesimpl.h:327] UE4Editor_SlateCore!TBaseDelegate<FReply,FGeometry const & __ptr64,FPointerEvent const & __ptr64,int,SVerticalBox::FSlot * __ptr64>::Execute() [delegatesignatureimpl.inl:537] UE4Editor_SlateCore!SDragAndDropVerticalBox::OnDragDetected() [sboxpanel.cpp:321] UE4Editor_Slate!<lambda_3d2f0c0de9bfb1f26dd3fbfeef226ad5>::operator() [slateapplication.cpp:5169] UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FDirectPolicy,FPointerEvent,<lambda_3d2f0c0de9bfb1f26dd3fbfeef226ad5> >() [slateapplication.cpp:239] UE4Editor_Slate!FSlateApplication::RoutePointerMoveEvent() [slateapplication.cpp:5167] UE4Editor_Slate!FSlateApplication::ProcessMouseMoveEvent() [slateapplication.cpp:5713] UE4Editor_Slate!FSlateApplication::OnMouseMove() [slateapplication.cpp:5647] UE4Editor_Core!FWindowsApplication::ProcessDeferredMessage() [windowsapplication.cpp:1742] UE4Editor_Core!FWindowsApplication::DeferMessage() [windowsapplication.cpp:2127] UE4Editor_Core!FWindowsApplication::ProcessMessage() [windowsapplication.cpp:867] UE4Editor_Core!FWindowsApplication::AppWndProc() [windowsapplication.cpp:714] user32!UserCallWinProcCheckWow() user32!DispatchMessageWorker() UE4Editor_Core!FWindowsPlatformMisc::PumpMessages() [windowsplatformmisc.cpp:1009] UE4Editor!FEngineLoop::Tick() [launchengineloop.cpp:3058] UE4Editor!GuardedMain() [launch.cpp:166] UE4Editor!GuardedMainWrapper() [launchwindows.cpp:134] UE4Editor!WinMain() [launchwindows.cpp:210] UE4Editor!__scrt_common_main_seh() [exe_common.inl:253] kernel32!BaseThreadInitThunk() ntdll!RtlUserThreadStart()
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