Description

This is a regression. Tested in //UE4/Release-4.27 CL18319896
In UE4 an error is thrown when attempting to add an input.

A Blueprint containing a Macro with a Wild Card input crashes when a Custom Event node has an additional input added. Once the project is restarted adding a new input to the Custom Event no longer triggers a crash until another Wild Card is added to the Macro.

Steps to Reproduce
  1. Create or open any project
  2. Create Blueprint actor
  3. Add a Custom event to the Event Graph
  4. Add an input parameter to the Custom Event
  5. Create a new Macro and add it to the Event Graph
  6. Add a Wildcard input parameter to the Macro
  7. Add a new input parameter to the Custom Event

Expected Results:
The Custom Event gets a new input parameter

Actual Results:
Editor Crashes

Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x0000000000000001
Callstack
Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x0000000000000001
ucrtbase!7ff9cb7e0000  + 2544d
ucrtbase!7ff9cb7e0000  + 10c24
ucrtbase!7ff9cb7e0000  + 1083e
UnrealEditor-Core!FString::PrintfImpl(wchar_t const *,...) [String.cpp:1724]
UnrealEditor-Kismet!FBlueprintGraphArgumentGroupLayout::GenerateChildContent(IDetailChildrenBuilder &) [BlueprintDetailsCustomization.cpp:3045]
UnrealEditor-PropertyEditor!FDetailCustomBuilderRow::OnGenerateChildren(TArray<TSharedRef<FDetailTreeNode,1>,TSizedDefaultAllocator<32> > &) [DetailCustomBuilderRow.cpp:67]
UnrealEditor-PropertyEditor!FDetailItemNode::GenerateChildren(bool) [DetailItemNode.cpp:414]
UnrealEditor-PropertyEditor!TBaseSPMethodDelegateInstance<0,FDetailItemNode,1,void ,FDefaultDelegateUserPolicy,bool>::ExecuteIfSafe() [DelegateInstancesImpl.h:307]
UnrealEditor-Kismet!FBaseBlueprintGraphActionDetails::OnPostEditorRefresh() [BlueprintDetailsCustomization.cpp:4197]
UnrealEditor-Kismet!TBaseSPMethodDelegateInstance<0,FBlueprintGraphActionDetails,1,void ,FDefaultDelegateUserPolicy>::ExecuteIfSafe() [DelegateInstancesImpl.h:307]
UnrealEditor-Kismet!TMulticastDelegate<void ,FDefaultDelegateUserPolicy>::Broadcast() [DelegateSignatureImpl.inl:967]
UnrealEditor-Kismet!FBlueprintEditor::RefreshEditors(ERefreshBlueprintEditorReason::Type) [BlueprintEditor.cpp:1042]
UnrealEditor-Kismet!FBlueprintEditor::OnBlueprintChangedImpl(UBlueprint *,bool) [BlueprintEditor.cpp:3782]
UnrealEditor-Kismet!bool TBaseSPMethodDelegateInstance<0,FBlueprintEditor,1,void __cdecl(UBlueprint *) [DelegateInstancesImpl.h:307]
UnrealEditor-Engine!void TMulticastDelegate<void __cdecl(UBlueprint *) [DelegateSignatureImpl.inl:967]
UnrealEditor-UnrealEd!7ff9459a0000  + 9104a7
UnrealEditor-BlueprintGraph!UEdGraphSchema_K2::HandleParameterDefaultValueChanged(UK2Node *) [EdGraphSchema_K2.cpp:7457]
UnrealEditor-Kismet!FBaseBlueprintGraphActionDetails::OnParamsChanged(UK2Node_EditablePinBase *,bool) [BlueprintDetailsCustomization.cpp:4566]
UnrealEditor-Kismet!FBaseBlueprintGraphActionDetails::OnAddNewInputClicked() [BlueprintDetailsCustomization.cpp:5432]
UnrealEditor-Kismet!TBaseSPMethodDelegateInstance<0,FBlueprintGraphActionDetails,1,FReply ,FDefaultDelegateUserPolicy>::Execute() [DelegateInstancesImpl.h:290]
UnrealEditor-Slate!7ff998020000  + 26ba3b
UnrealEditor-Slate!7ff998020000  + 292df6
UnrealEditor-Slate!7ff998020000  + 34034
UnrealEditor-Slate!7ff998020000  + 16fc6
UnrealEditor-Slate!7ff998020000  + 902ee
UnrealEditor-Slate!7ff998020000  + 791b1
UnrealEditor-Slate!7ff998020000  + 6d5dc
UnrealEditor-ApplicationCore!FWindowsApplication::ProcessDeferredMessage(FDeferredWindowsMessage const &) [WindowsApplication.cpp:2210]
UnrealEditor-ApplicationCore!FWindowsApplication::DeferMessage(TSharedPtr<FWindowsWindow,1> &,HWND__ *,unsigned int,unsigned __int64,__int64,int,int,unsigned int) [WindowsApplication.cpp:2699]
UnrealEditor-ApplicationCore!FWindowsApplication::ProcessMessage(HWND__ *,unsigned int,unsigned __int64,__int64) [WindowsApplication.cpp:1078]
UnrealEditor-ApplicationCore!FWindowsApplication::AppWndProc(HWND__ *,unsigned int,unsigned __int64,__int64) [WindowsApplication.cpp:916]
USER32!7ff9ccca0000  + 15c0d
USER32!7ff9ccca0000  + 158de
InkObj!7ff9229f0000  + 166f2
atlthunk!7ff9b52c0000  + 1028
USER32!7ff9ccca0000  + 15c0d
USER32!7ff9ccca0000  + 15602
UnrealEditor-ApplicationCore!FWindowsPlatformApplicationMisc::PumpMessages(bool) [WindowsPlatformApplicationMisc.cpp:138]
UnrealEditor!7ff78f820000  + 7114
UnrealEditor!7ff78f820000  + 20d9c
UnrealEditor!7ff78f820000  + 20e8a
UnrealEditor!7ff78f820000  + 23c4d
UnrealEditor!7ff78f820000  + 35564
UnrealEditor!7ff78f820000  + 38736
KERNEL32!7ff9ccb30000  + 17c24
ntdll!7ff9ce4e0000  + 6d721

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Duplicate
ComponentUE - Gameplay - Blueprint
Affects Versions5.0.3
Target Fix5.1
Fix Commit21342538
Main Commit21342538
CreatedAug 16, 2022
ResolvedAug 31, 2022
UpdatedAug 31, 2022