Crash compiling almost empty Object BP with just an EventDispatcher on it

Development World Creation
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Right now on Main (synced from Epic’s P4 directly at CL 16884875, not the UE 5.0EA build) there’s a crash that occurs when you do the following:

  • Create a new BP inheriting from Object and change it’s not to something like ‘BP_Test’.
  • Add an EventDispatcher to it and change its name to something like ‘Test’.
  • Compile and watch it crash.

The FMulticastDelegateProperty representing the EventDispatcher has a SignatureFunction that is a dangling pointer due to a GC occurrence that happens sometime during compilation. I added a temporary UFunction destructor so I could see when it got GC’d to verify that’s what the problem was.

Other notes:

  • Performing the same steps on a blank AActor does not crash.
  • If you save after the name change, close the BP’s window, reopen the BP, then compile, it doesn’t crash.
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Note: The crash will also occur if you try to add an EventDispatcher to a SubLevel or a LevelInstance, rename and compile.