Editor will crash when trying to change the parent class of a component that is part of a Blueprint Hierarchy

Changing the inherited parent class of a component that is part of a blueprint hierarchy will cause the editor to crash and prevent the project from opening even if the inherited parent is changed back to the original class.

1. Open UE4 Editor (any project
2. Add code to project based on SceneComponent (TestComp)
3. Create blueprint based on Actor (MyActorBP)
4. Add TestComp component to MyActorBP
5. In Code, add include statement for "Components/StaticMeshComponent.h"
6. Change the class inheritance line of the .h file
   • From:

     class MYPROJECT19_API UMySceneComponent : public USceneComponent
     

   • To:

     class MYPROJECT19_API UMySceneComponent : public UStaticMeshComponent
     

7. Compile

Result:
If the editor is open, this will cause the editor to immediately crash. After compiling these changes, the project will crash on load

Expected:
Either the component is treated as a static mesh component or a warning is thrown when attempting to change the parent class.