User comment from crash group:
No known steps to reproduce at this time
I believe the the repro was to create a new layer or blend asset from the material editor or material instance editor. This CL disables that ability
Assertion failed: (Index >= 0) & (Index < ArrayNum) [File:D:\Build\++UE4+Release-4.19+Compile\Sync\Engine\Source\Runtime\Core\Public\Containers/Array.h] [Line: 610] Array index out of bounds: 0 from an array of size 0 UE4Editor_Engine!FExpressionInput::Connect() [materialshared.cpp:129] UE4Editor_Engine!UMaterialExpressionMaterialAttributeLayers::RebuildLayerGraph() [materialexpressions.cpp:5137] UE4Editor_Engine!UMaterial::RebuildMaterialFunctionInfo() [material.cpp:3149] UE4Editor_Engine!UMaterial::CacheShadersForResources() [material.cpp:3039] UE4Editor_Engine!UMaterial::CacheResourceShadersForRendering() [material.cpp:2964] UE4Editor_Engine!UMaterial::PostEditChangeProperty() [material.cpp:4145] UE4Editor_CoreUObject!UObject::PostEditChange() [obj.cpp:333] UE4Editor_MaterialEditor!UMaterialEditingLibrary::UpdateMaterialFunction() [materialeditinglibrary.cpp:629] UE4Editor_MaterialEditor!FMaterialEditor::UpdateOriginalMaterial() [materialeditor.cpp:1665] UE4Editor_MaterialEditor!FMaterialEditor::SaveAsset_Execute() [materialeditor.cpp:1116] UE4Editor_UnrealEd!TBaseSPMethodDelegateInstance<0,FAssetEditorToolkit,0,TTypeWrapper<void> __cdecl() [delegateinstancesimpl.h:269] UE4Editor_UnrealEd!TBaseSPMethodDelegateInstance<0,FAssetEditorToolkit,0,void __cdecl() [delegateinstancesimpl.h:345] UE4Editor_Slate!FUICommandList::ExecuteAction() [uicommandlist.cpp:97] UE4Editor_Slate!SToolBarButtonBlock::OnClicked() [stoolbarbuttonblock.cpp:300] UE4Editor_Slate!TMemberFunctionCaller<SToolBarButtonBlock,FReply() [delegateinstanceinterface.h:156] UE4Editor_Slate!UE4Tuple_Private::TTupleImpl<TIntegerSequence<unsigned int> >::ApplyAfter<TMemberFunctionCaller<SToolBarButtonBlock,FReply() [tuple.h:498] UE4Editor_Slate!TBaseSPMethodDelegateInstance<0,SToolBarButtonBlock,0,FReply __cdecl() [delegateinstancesimpl.h:269] UE4Editor_Slate!TBaseDelegate<FReply>::Execute() [delegatesignatureimpl.inl:537] UE4Editor_Slate!SButton::OnMouseButtonUp() [sbutton.cpp:282] UE4Editor_Slate!<lambda_1002768c627006711ef2f351a87ec0e7>::operator() [slateapplication.cpp:5435] UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FToLeafmostPolicy,FPointerEvent,<lambda_1002768c627006711ef2f351a87ec0e7> >() [slateapplication.cpp:266] UE4Editor_Slate!FSlateApplication::RoutePointerUpEvent() [slateapplication.cpp:5424] UE4Editor_Slate!FSlateApplication::ProcessMouseButtonUpEvent() [slateapplication.cpp:5922] UE4Editor_Slate!FSlateApplication::OnMouseUp() [slateapplication.cpp:5902] UE4Editor_ApplicationCore!FWindowsApplication::ProcessDeferredMessage() [windowsapplication.cpp:1726] UE4Editor_ApplicationCore!FWindowsApplication::DeferMessage() [windowsapplication.cpp:2172] UE4Editor_ApplicationCore!FWindowsApplication::ProcessMessage() [windowsapplication.cpp:889] UE4Editor_ApplicationCore!FWindowsApplication::AppWndProc() [windowsapplication.cpp:726] user32!UserCallWinProcCheckWow() user32!DispatchMessageWorker() UE4Editor_ApplicationCore!FWindowsPlatformApplicationMisc::PumpMessages() [windowsplatformapplicationmisc.cpp:129] UE4Editor!FEngineLoop::Tick() [launchengineloop.cpp:3244] 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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