This was the simplest solid repro I could get on this bug. The callstack is similar to [Link Removed]
Also came across several Shader Compiling Manager crashes while attempting to repro this crash but no repro ever worked twice like [Link Removed]
This does NOT happen in 4.14.2 so this is a Regression
Repro using regular materials:
Result: The Editor crashes
Expected Result: The material successfully deletes
-------------
Repro using Landscape
Result: The Editor crashes
Expected Result: The material successfully deletes and the landscape goes back to default material
UE4Editor_Engine!GetIndexedTexture() materialuniformexpressions.h:273 UE4Editor_Engine!FMaterialUniformExpressionTextureParameter::GetGameThreadTextureValue() materialuniformexpressions.h:340 UE4Editor_Engine!UMaterialInstance::GetTextureExpressionValues() materialinstance.cpp:695 UE4Editor_Engine!UMaterialInstance::GetUsedTextures() materialinstance.cpp:737 UE4Editor_Engine!UMaterialInstance::UpdateLightmassTextureTracking() materialinstance.cpp:2462 UE4Editor_Engine!UMaterialInstance::PostEditChangeProperty() materialinstance.cpp:2440 UE4Editor_Engine!UMaterialInstanceConstant::PostEditChangeProperty() materialinstanceconstant.cpp:20 UE4Editor_UnrealEd!ObjectTools::ForceReplaceReferences() objecttools.cpp:755 UE4Editor_UnrealEd!ObjectTools::ForceDeleteObjects() objecttools.cpp:2248 UE4Editor_UnrealEd!FAssetDeleteModel::DoForceDelete() assetdeletemodel.cpp:316 UE4Editor_UnrealEd!SDeleteAssetsDialog::ForceDelete() sdeleteassetsdialog.cpp:717 UE4Editor_UnrealEd!TMemberFunctionCaller<SDeleteAssetsDialog,FReply() delegateinstanceinterface.h:165 UE4Editor_UnrealEd!TTupleImpl<TIntegerSequence<unsigned int> >::ApplyAfter<TMemberFunctionCaller<SDeleteAssetsDialog,FReply() tuple.h:134 UE4Editor_UnrealEd!TBaseSPMethodDelegateInstance<0,SDeleteAssetsDialog,0,FReply __cdecl() delegateinstancesimpl.h:327 UE4Editor_Slate!TBaseDelegate<FReply>::Execute() delegatesignatureimpl.inl:537 UE4Editor_Slate!SButton::OnMouseButtonUp() sbutton.cpp:278 UE4Editor_Slate!<lambda_8d0e9a1da76abd0a756a3a9d775f5ed1>::operator() slateapplication.cpp:5052 UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FToLeafmostPolicy,FPointerEvent,<lambda_8d0e9a1da76abd0a756a3a9d775f5ed1> >() slateapplication.cpp:238 UE4Editor_Slate!FSlateApplication::RoutePointerUpEvent() slateapplication.cpp:5041 UE4Editor_Slate!FSlateApplication::ProcessMouseButtonUpEvent() slateapplication.cpp:5504 UE4Editor_Slate!FSlateApplication::OnMouseUp() slateapplication.cpp:5481 UE4Editor_Core!FWindowsApplication::ProcessDeferredMessage() windowsapplication.cpp:1698 UE4Editor_Core!FWindowsApplication::DeferMessage() windowsapplication.cpp:2120 UE4Editor_Core!FWindowsApplication::ProcessMessage() windowsapplication.cpp:867 UE4Editor_Core!FWindowsApplication::AppWndProc() windowsapplication.cpp:714 user32!<Unknown> user32!<Unknown> UE4Editor_Core!FWindowsApplication::PumpMessages() windowsapplication.cpp:2132 UE4Editor_Slate!FSlateApplication::TickPlatform() slateapplication.cpp:1533 UE4Editor_Slate!FSlateApplication::AddModalWindow() slateapplication.cpp:2040 UE4Editor_UnrealEd!UEditorEngine::EditorAddModalWindow() editorengine.cpp:3814 UE4Editor_UnrealEd!ObjectTools::DeleteObjects() objecttools.cpp:1780 UE4Editor_UnrealEd!ObjectTools::DeleteAssets() objecttools.cpp:1687 UE4Editor_ContentBrowser!FAssetContextMenu::ExecuteDelete() assetcontextmenu.cpp:1824 UE4Editor_ContentBrowser!SContentBrowser::HandleDeleteCommandExecute() scontentbrowser.cpp:2052 UE4Editor_ContentBrowser!TBaseSPMethodDelegateInstance<0,SContentBrowser,0,TTypeWrapper<void> __cdecl() delegateinstancesimpl.h:327 UE4Editor_ContentBrowser!TBaseSPMethodDelegateInstance<0,SContentBrowser,0,void __cdecl() delegateinstancesimpl.h:433 UE4Editor_Slate!FUICommandList::ConditionalProcessCommandBindings() uicommandlist.cpp:216 UE4Editor_Slate!FUICommandList::ProcessCommandBindings() uicommandlist.cpp:160 UE4Editor_ContentBrowser!SContentBrowser::OnKeyDown() scontentbrowser.cpp:1026 UE4Editor_Slate!<lambda_2afcd964c763e269e2d1a63f3a72f846>::operator() slateapplication.cpp:4668 UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FBubblePolicy,FKeyEvent,<lambda_2afcd964c763e269e2d1a63f3a72f846> >() slateapplication.cpp:238 UE4Editor_Slate!FEventRouter::RouteAlongFocusPath<FEventRouter::FBubblePolicy,<lambda_2afcd964c763e269e2d1a63f3a72f846>,FKeyEvent>() slateapplication.cpp:220 UE4Editor_Slate!FSlateApplication::ProcessKeyDownEvent() slateapplication.cpp:4666 UE4Editor_Slate!FSlateApplication::OnKeyDown() slateapplication.cpp:4581 UE4Editor_Core!FWindowsApplication::ProcessDeferredMessage() windowsapplication.cpp:1533 UE4Editor_Core!FWindowsApplication::DeferMessage() windowsapplication.cpp:2120 UE4Editor_Core!FWindowsApplication::ProcessMessage() windowsapplication.cpp:867 UE4Editor_Core!FWindowsApplication::AppWndProc() windowsapplication.cpp:714 user32!<Unknown> user32!<Unknown> UE4Editor_Core!FWindowsPlatformMisc::PumpMessages() windowsplatformmisc.cpp:979 UE4Editor!FEngineLoop::Tick() launchengineloop.cpp:2971 UE4Editor!GuardedMain() launch.cpp:166 UE4Editor!GuardedMainWrapper() launchwindows.cpp:130 UE4Editor!WinMain() launchwindows.cpp:206 UE4Editor!__scrt_common_main_seh() exe_common.inl:264 kernel32!<Unknown> ntdll!<Unknown>
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