Adding a Material Layer to a Material Instance that has a Material Function Call node connected to the Set Material Attributes node causes the editor to crash. I tested a Material Layer without the Material Function Call and there was no crash.
Tested in //UE4/Release-4.25 @ CL 14469661 and this did not occur, so marking as a Regression.
Quick Repro:
RESULT:
The editor crashes
EXPECTED:
The user would be able to add a Material Layer with a MaterialFunctionCall to a Material Instance without error
=== Critical error: === Assertion failed: (Index >= 0) & (Index < ArrayNum) [File:D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Public\Containers/Array.h] [Line: 674] Array index out of bounds: 0 from an array of size 0 [Callstack] 0x00007ff876053b29 KERNELBASE.dll!UnknownFunction [] [Callstack] 0x00007ff80707d096 UE4Editor-Core.dll!ReportAssert() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Private\Windows\WindowsPlatformCrashContext.cpp:1627] [Callstack] 0x00007ff8070807f8 UE4Editor-Core.dll!FWindowsErrorOutputDevice::Serialize() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Private\Windows\WindowsErrorOutputDevice.cpp:78] [Callstack] 0x00007ff806d8e98d UE4Editor-Core.dll!FOutputDevice::LogfImpl() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Private\Misc\OutputDevice.cpp:61] [Callstack] 0x00007ff806d25625 UE4Editor-Core.dll!AssertFailedImplV() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Private\Misc\AssertionMacros.cpp:104] [Callstack] 0x00007ff806d276d0 UE4Editor-Core.dll!FDebug::CheckVerifyFailedImpl() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Private\Misc\AssertionMacros.cpp:461] [Callstack] 0x00007ff804ef01d8 UE4Editor-Engine.dll!DispatchCheckVerify<void,<lambda_a42d0919e8303add9bf9f7b44044abc5> >() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Public\Misc\AssertionMacros.h:165] [Callstack] 0x00007ff803f06e0c UE4Editor-Engine.dll!FMaterialCachedExpressionData::UpdateForExpressions() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\Materials\MaterialCachedData.cpp:528] [Callstack] 0x00007ff803e9d69d UE4Editor-Engine.dll!<lambda_3a4808425eca5b1b87ead9d0466f5a48>::operator()() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\Materials\MaterialCachedData.cpp:222] [Callstack] 0x00007ff803ee6ef2 UE4Editor-Engine.dll!UMaterialExpressionMaterialFunctionCall::IterateDependentFunctions() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\Materials\MaterialExpressions.cpp:13255] [Callstack] 0x00007ff803ee6fcd UE4Editor-Engine.dll!UMaterialFunction::IterateDependentFunctions() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\Materials\MaterialExpressions.cpp:12000] [Callstack] 0x00007ff803f0857f UE4Editor-Engine.dll!FMaterialCachedExpressionData::UpdateForFunction() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\Materials\MaterialCachedData.cpp:237] [Callstack] 0x00007ff803f08632 UE4Editor-Engine.dll!FMaterialCachedExpressionData::UpdateForLayerFunctions() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\Materials\MaterialCachedData.cpp:247] [Callstack] 0x00007ff803f97002 UE4Editor-Engine.dll!UMaterialInstance::UpdateCachedLayerParameters() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\Materials\MaterialInstance.cpp:4031] [Callstack] 0x00007ff8018c368a UE4Editor-UnrealEd.dll!UMaterialEditorInstanceConstant::RegenerateArrays() [D:\Build\++UE4\Sync\Engine\Source\Editor\UnrealEd\Private\PreviewMaterial.cpp:978] [Callstack] 0x00007ff8018bf9f2 UE4Editor-UnrealEd.dll!UMaterialEditorInstanceConstant::PostEditChangeProperty() [D:\Build\++UE4\Sync\Engine\Source\Editor\UnrealEd\Private\PreviewMaterial.cpp:877] [Callstack] 0x00007ff806684ff0 UE4Editor-CoreUObject.dll!UObject::PostEditChangeChainProperty() [D:\Build\++UE4\Sync\Engine\Source\Runtime\CoreUObject\Private\UObject\Obj.cpp:454] [Callstack] 0x00007ffffc7c6d44 UE4Editor-PropertyEditor.dll!FPropertyNode::NotifyPostChange() [D:\Build\++UE4\Sync\Engine\Source\Editor\PropertyEditor\Private\PropertyNode.cpp:2342] [Callstack] 0x00007ffffc7c6559 UE4Editor-PropertyEditor.dll!FPropertyHandleBase::NotifyPostChange() [D:\Build\++UE4\Sync\Engine\Source\Editor\PropertyEditor\Private\PropertyHandleImpl.cpp:3074] [Callstack] 0x00007ffffcd26d49 UE4Editor-MaterialEditor.dll!FMaterialPropertyHelpers::OnMaterialLayerAssetChanged() [D:\Build\++UE4\Sync\Engine\Source\Editor\MaterialEditor\Private\MaterialPropertyHelpers.cpp:143] [Callstack] 0x00007ffffcd47d69 UE4Editor-MaterialEditor.dll!SMaterialLayersFunctionsInstanceTree::RefreshOnAssetChange() [D:\Build\++UE4\Sync\Engine\Source\Editor\MaterialEditor\Private\SMaterialLayersFunctionsTree.cpp:1183] [Callstack] 0x00007ffffcce5662 UE4Editor-MaterialEditor.dll!TBaseSPMethodDelegateInstance<0,SMaterialLayersFunctionsInstanceTree,0,void __cdecl(FAssetData const &),FDefaultDelegateUserPolicy,int,enum EMaterialParameterAssociation>::ExecuteIfSafe() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:307] [Callstack] 0x00007ffffc7e9c2d UE4Editor-PropertyEditor.dll!SObjectPropertyEntryBox::OnSetObject() [D:\Build\++UE4\Sync\Engine\Source\Editor\PropertyEditor\Private\PropertyCustomizationHelpers.cpp:576] [Callstack] 0x00007ffffc775f47 UE4Editor-PropertyEditor.dll!TBaseSPMethodDelegateInstance<0,SObjectPropertyEntryBox,0,void __cdecl(FAssetData const &),FDefaultDelegateUserPolicy>::ExecuteIfSafe() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:307] [Callstack] 0x00007ffffc91129f UE4Editor-PropertyEditor.dll!SPropertyEditorAsset::SetValue() [D:\Build\++UE4\Sync\Engine\Source\Editor\PropertyEditor\Private\UserInterface\PropertyEditor\SPropertyEditorAsset.cpp:941] [Callstack] 0x00007ffffc8b1a67 UE4Editor-PropertyEditor.dll!TBaseSPMethodDelegateInstance<0,SPropertyEditorAsset,0,void __cdecl(FAssetData const &),FDefaultDelegateUserPolicy>::ExecuteIfSafe() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:307] [Callstack] 0x00007ffffc8dfdb4 UE4Editor-PropertyEditor.dll!SPropertyMenuAssetPicker::OnAssetSelected() [D:\Build\++UE4\Sync\Engine\Source\Editor\PropertyEditor\Private\UserInterface\PropertyEditor\SPropertyMenuAssetPicker.cpp:279] [Callstack] 0x00007ffffc8b3087 UE4Editor-PropertyEditor.dll!TBaseSPMethodDelegateInstance<0,SPropertyMenuAssetPicker,0,void __cdecl(FAssetData const &),FDefaultDelegateUserPolicy>::ExecuteIfSafe() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:307] [Callstack] 0x00007ffff82086b6 UE4Editor-ContentBrowser.dll!SAssetPicker::HandleItemSelectionChanged() [D:\Build\++UE4\Sync\Engine\Source\Editor\ContentBrowser\Private\SAssetPicker.cpp:528] [Callstack] 0x00007ffff81e7877 UE4Editor-ContentBrowser.dll!TBaseSPMethodDelegateInstance<0,SAssetPicker,0,void __cdecl(FContentBrowserItem const &,enum ESelectInfo::Type),FDefaultDelegateUserPolicy>::ExecuteIfSafe() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:307] [Callstack] 0x00007ffff81a492b UE4Editor-ContentBrowser.dll!SAssetView::AssetSelectionChanged() [D:\Build\++UE4\Sync\Engine\Source\Editor\ContentBrowser\Private\SAssetView.cpp:3324] [Callstack] 0x00007ffff81e9637 UE4Editor-ContentBrowser.dll!TBaseSPMethodDelegateInstance<0,SAssetView,0,void __cdecl(TSharedPtr<FAssetViewItem,0>,enum ESelectInfo::Type),FDefaultDelegateUserPolicy>::ExecuteIfSafe() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Public\Delegates\DelegateInstancesImpl.h:307] [Callstack] 0x00007ffff8236b76 UE4Editor-ContentBrowser.dll!SListView<TSharedPtr<FAssetViewItem,0> >::Private_SignalSelectionChanged() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Slate\Public\Widgets\Views\SListView.h:947] [Callstack] 0x00007ffff822c5ad UE4Editor-ContentBrowser.dll!STableRow<TSharedPtr<FAssetViewItem,0> >::OnMouseButtonUp() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Slate\Public\Widgets\Views\STableRow.h:617] [Callstack] 0x00007ff802b546be UE4Editor-Slate.dll!FEventRouter::Route<FReply,FEventRouter::FToLeafmostPolicy,FPointerEvent,<lambda_cc5aea9e7377b04ce85c30c65ec3889b> >() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:378] [Callstack] 0x00007ff802bd7f54 UE4Editor-Slate.dll!FSlateApplication::RoutePointerUpEvent() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:4815] [Callstack] 0x00007ff802bc0367 UE4Editor-Slate.dll!FSlateApplication::ProcessMouseButtonUpEvent() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:5356] [Callstack] 0x00007ff802bb3642 UE4Editor-Slate.dll!FSlateApplication::OnMouseUp() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Slate\Private\Framework\Application\SlateApplication.cpp:5321] [Callstack] 0x00007ff85646bca5 UE4Editor-ApplicationCore.dll!FWindowsApplication::ProcessDeferredMessage() [D:\Build\++UE4\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:2174] [Callstack] 0x00007ff856459197 UE4Editor-ApplicationCore.dll!FWindowsApplication::DeferMessage() [D:\Build\++UE4\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:2638] [Callstack] 0x00007ff85646e379 UE4Editor-ApplicationCore.dll!FWindowsApplication::ProcessMessage() [D:\Build\++UE4\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:1042] [Callstack] 0x00007ff856454310 UE4Editor-ApplicationCore.dll!FWindowsApplication::AppWndProc() [D:\Build\++UE4\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsApplication.cpp:874] [Callstack] 0x00007ff878135c1d USER32.dll!UnknownFunction [] [Callstack] 0x00007ff878135612 USER32.dll!UnknownFunction [] [Callstack] 0x00007ff85646f904 UE4Editor-ApplicationCore.dll!FWindowsPlatformApplicationMisc::PumpMessages() [D:\Build\++UE4\Sync\Engine\Source\Runtime\ApplicationCore\Private\Windows\WindowsPlatformApplicationMisc.cpp:130] [Callstack] 0x00007ff75e938857 UE4Editor.exe!FEngineLoop::Tick() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Launch\Private\LaunchEngineLoop.cpp:4748] [Callstack] 0x00007ff75e9511ac UE4Editor.exe!GuardedMain() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Launch\Private\Launch.cpp:169] [Callstack] 0x00007ff75e95128a UE4Editor.exe!GuardedMainWrapper() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:137] [Callstack] 0x00007ff75e9652ed UE4Editor.exe!WinMain() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:268] [Callstack] 0x00007ff75e96801a UE4Editor.exe!__scrt_common_main_seh() [d:\agent\_work\5\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288] [Callstack] 0x00007ff878ac7c24 KERNEL32.DLL!UnknownFunction [] [Callstack] 0x00007ff87908d721 ntdll.dll!UnknownFunction []
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-112402 in the post.