Developer Notes

Outdated practice, workflow has been updated.


When using a code created function call inside of a blueprint that takes in a pointer to a UBlueprint as a paramter the pin for setting the desired blueprint will cause a compile error when the editor is closed/reopened.

Manually setting the blueprint pin value will allow the blueprint to compile but will then be broken again after the next launch of the editor.

Steps to Reproduce

1. Open UE4Editor (code based project with starter content)
2. Add new class based on Actor (MyActor)
3. In the header for MyActor add the following:

	UFUNCTION(BlueprintCallable, Category = test)
		void FunctionCallTest(UBlueprint* blueprint);

4. In the source for MyActor add the following:

void AMyActor::FunctionCallTest(UBlueprint* blueprint)


5. Compile
6. Create a blueprint based on MyActor (MyActorBP)
7. In the event graph of MyActorBP right click and make a call to FunctionCallTest and wire to Event Begin Play
8. Set the Blueprint pin of the function node to Blueprint_Effect_Sparks
9. Compile the blueprint
10. Save the blueprint and project
11. Close/Reopen the editor
12. Reopen MyActorBP

Blueprint won't compile and function node shows an error.

Blueprints that are compiled remain clean after relaunching the editor.

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Won't Fix
ComponentUE - Gameplay - Blueprint
Affects Versions4.7.64.8
CreatedJun 8, 2015
ResolvedJun 15, 2015
UpdatedJul 14, 2021