[Bug] Adding EventBeginPlay crashes the editor

This happens in 4.5

It can be reproduced like this:

  1. Create a new blueprint

  2. Add 1 or more graphs to the blueprint.

  3. Add EventBeginPlay to the default event graph

  4. Add EventBeginPlay to one of the created graphs -

  5. And the editor crashes with this error message:

    Assertion failed: NodeToAdd->GetOuter() == this [File:C:\Programs\UE4.5\Engine\Source\Runtime\Engine\Private\EdGraph\EdGraph.cpp] [Line: 129]

    KERNELBASE.dll!UnknownFunction (0x00007ffd1d1d606c) + 0 bytes [UnknownFile:0]
    UE4Editor-Core.dll!FOutputDeviceWindowsError::Serialize() (0x00007ffcf6f67c2d) + 0 bytes [c:\programs\ue4.5\engine\source\runtime\core\private\windows\windowsplatformoutputdevices.cpp:95]
    UE4Editor-Core.dll!FOutputDevice::Logf__VA() (0x00007ffcf6e05878) + 159 bytes [c:\programs\ue4.5\engine\source\runtime\core\private\misc\outputdevice.cpp:145]
    UE4Editor-Core.dll!FDebug::AssertFailed() (0x00007ffcf6de8632) + 62 bytes [c:\programs\ue4.5\engine\source\runtime\core\private\misc\outputdevice.cpp:220]
    UE4Editor-Engine.dll!UEdGraph::AddNode() (0x00007ffcf2182ee3) + 0 bytes [c:\programs\ue4.5\engine\source\runtime\engine\private\edgraph\edgraph.cpp:134]
    UE4Editor-Kismet.dll!FBlueprintActionMenuItem::PerformAction() (0x00007ffcf467d544) + 0 bytes [c:\programs\ue4.5\engine\source\editor\kismet\private\blueprintactionmenuitem.cpp:113]
    UE4Editor-Kismet.dll!FBlueprintActionMenuItem::PerformAction() (0x00007ffcf467d333) + 0 bytes [c:\programs\ue4.5\engine\source\editor\kismet\private\blueprintactionmenuitem.cpp:152]
    UE4Editor-Kismet.dll!SBlueprintActionMenu::OnActionSelected() (0x00007ffcf4792bcb) + 0 bytes [c:\programs\ue4.5\engine\source\editor\kismet\private\sblueprintactionmenu.cpp:454]
    UE4Editor-Kismet.dll!TBaseSPMethodDelegateInstance_OneParam<SBlueprintActionMenu,void,TArray<TSharedPtr<FEdGraphSchemaAction,0>,FDefaultAllocator> const & __ptr64,0>::Execute() (0x00007ffcf474f3a8) + 15 bytes [c:\programs\ue4.5\engine\source\runtime\core\public\delegates\delegateinstancesimpl.inl:161]
    UE4Editor-GraphEditor.dll!SGraphActionMenu::HandleSelection() (0x00007ffceefc5269) + 0 bytes [c:\programs\ue4.5\engine\source\editor\grapheditor\private\sgraphactionmenu.cpp:1160]
    UE4Editor-GraphEditor.dll!SGraphActionMenu::OnMouseButtonDownEvent() (0x00007ffceeffa575) + 13 bytes [c:\programs\ue4.5\engine\source\editor\grapheditor\private\sgraphactionmenu.cpp:1057]
    UE4Editor-GraphEditor.dll!TBaseSPMethodDelegateInstance_RetVal_OneParam<SGraphActionMenu,bool,TWeakPtr<FEdGraphSchemaAction,0>,0>::Execute() (0x00007ffceef8e20c) + 42 bytes [c:\programs\ue4.5\engine\source\runtime\core\public\delegates\delegateinstancesimpl.inl:161]
    UE4Editor-GraphEditor.dll!TBaseDelegate_RetVal_OneParam<bool,TWeakPtr<FEdGraphSchemaAction,0> >::Execute() (0x00007ffceef88ee2) + 36 bytes [c:\programs\ue4.5\engine\source\runtime\core\public\delegates\delegatesignatureimpl.inl:1058]
    UE4Editor-GraphEditor.dll!SGraphPaletteItem::OnMouseButtonDown() (0x00007ffceeff9954) + 49 bytes [c:\programs\ue4.5\engine\source\editor\grapheditor\private\sgraphpalette.cpp:87]
    UE4Editor-Slate.dll!FSlateApplication::ProcessMouseButtonDownEvent() (0x00007ffcf600d8ef) + 23 bytes [c:\programs\ue4.5\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:3330]
    UE4Editor-Slate.dll!FSlateApplication::OnMouseDown() (0x00007ffcf5ffaf9b) + 19 bytes [c:\programs\ue4.5\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:3247]
    UE4Editor-Core.dll!FWindowsApplication::ProcessDeferredMessage() (0x00007ffcf6ee77f2) + 32 bytes [c:\programs\ue4.5\engine\source\runtime\core\private\windows\windowsapplication.cpp:1284]
    UE4Editor-Core.dll!FWindowsApplication::DeferMessage() (0x00007ffcf6ed3eab) + 74 bytes [c:\programs\ue4.5\engine\source\runtime\core\private\windows\windowsapplication.cpp:1637]
    UE4Editor-Core.dll!FWindowsApplication::ProcessMessage() (0x00007ffcf6ee8b29) + 41 bytes [c:\programs\ue4.5\engine\source\runtime\core\private\windows\windowsapplication.cpp:737]
    UE4Editor-Core.dll!FWindowsApplication::AppWndProc() (0x00007ffcf6ed07f2) + 0 bytes [c:\programs\ue4.5\engine\source\runtime\core\private\windows\windowsapplication.cpp:599]
    USER32.dll!UnknownFunction (0x00007ffd1ecc2434) + 0 bytes [UnknownFile:0]
    USER32.dll!UnknownFunction (0x00007ffd1ecc2297) + 0 bytes [UnknownFile:0]
    UE4Editor-Core.dll!FWindowsPlatformMisc::PumpMessages() (0x00007ffcf6ee8fe6) + 48 bytes [c:\programs\ue4.5\engine\source\runtime\core\private\windows\windowsplatformmisc.cpp:757]
    UE4Editor.exe!FEngineLoop::Tick() (0x00007ff6490e8f22) + 8 bytes [c:\programs\ue4.5\engine\source\runtime\launch\private\launchengineloop.cpp:2111]
    UE4Editor.exe!GuardedMain() (0x00007ff6490deb0e) + 0 bytes [c:\programs\ue4.5\engine\source\runtime\launch\private\launch.cpp:133]
    UE4Editor.exe!GuardedMainWrapper() (0x00007ff6490deb7a) + 5 bytes [c:\programs\ue4.5\engine\source\runtime\launch\private\windows\launchwindows.cpp:125]
    UE4Editor.exe!WinMain() (0x00007ff6490ea6f9) + 17 bytes [c:\programs\ue4.5\engine\source\runtime\launch\private\windows\launchwindows.cpp:201]
    UE4Editor.exe!__tmainCRTStartup() (0x00007ff6490eb629) + 21 bytes [f:\dd\vctools\crt\crtw32\dllstuff\crtexe.c:618]
    KERNEL32.DLL!UnknownFunction (0x00007ffd1f2116ad) + 0 bytes [UnknownFile:0]
    ntdll.dll!UnknownFunction (0x00007ffd1fcd4409) + 0 bytes [UnknownFile:0]
    ntdll.dll!UnknownFunction (0x00007ffd1fcd4409) + 0 bytes [UnknownFile:0]

Hello ,

I was unable to reproduce this issue on my end. Does this still occur when you use a clean project? Some other information you could provide would be:

  • dxdiag
  • Log
  • Crash report

This information will help up narrow down the issue.

Created a blank project - does not occur there.

Hello ,

Since the issue is not occurring in a clean project I would like for you to try it in any other projects that you may have. I would like for you to provide your Log file. This can be found under “YourProjectName”\Saved\Logs. It will be called “YourProjectName”.log. I would also like you to provide your dxdiag.

Quick Questions:

  1. When you create an “Event Begin Play” node does it bounce you back to the first instance of the node instead of creating a new one (this is currently what occurs normally)?

  2. Is it happening elsewhere (other projects)?

  1. It does not bounce me anywhere - it just crashes.
  2. No - just in one project.

Hello ,

Thank you for all of your information. This seems to be project specific. If you could send a stripped down version of your project with only the assets needed to reproduce the issue I would be more than happy to try and reproduce it on my end. This will get us another step closer to a possible solution.

Yes - it is project specific.
I deleted Binaries, DerivedDataCache, Intermediate and Saved folders and the editor is not crashing any more.

Hello ,

Without a version of the project with the crash there is no way for us to reproduce this on our end. I am going to go ahead and mark this as answered. If you are able to reproduce it feel free to send a version with the crash and will be happy to look into it further.