UEFN crashes when creating a circular reference with an editable attribute

General Issues and Bug Reporting
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1

Please select what you are reporting on:

Creative

What Type of Bug are you experiencing?

Assets

Summary

UEFN crashes when creating a circular reference with an editable attribute

Steps to Reproduce

using { /Fortnite.com/Devices }
using { /Verse.org/Simulation }
using { /UnrealEngine.com/Temporary/Diagnostics }

first_circle_ref_device := class(creative_device):

    @editable
    Second:second_circle_ref_device=second_circle_ref_device{}

    OnBegin<override>()<suspends>:void=
        Print("Hello, world!")
        Print("2 + 2 = {2 + 2}")

using { /Fortnite.com/Devices }
using { /Verse.org/Simulation }
using { /UnrealEngine.com/Temporary/Diagnostics }

second_circle_ref_device := class(creative_device):

    @editable
    First:first_circle_ref_device=first_circle_ref_device{}

    OnBegin<override>()<suspends>:void=
        Print("Hello, world!")
        Print("2 + 2 = {2 + 2}")

Placing the above two codes will cause the project to crash.

Expected Result

Should be able to issue a warning statement without crashing.

Observed Result

LoginId:96ba46114a08a9cee47493adaa079dd1
EpicAccountId:596871732bef4be18e2a5d8fc429a94a

Unhandled Exception: EXCEPTION_ACCESS_VIOLATION 0x0000000000000000

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kernel32
ntdll

This error happens.

Platform(s)

Windows10

2

Any fix ?

3

The status of FORT-722304 incident has been moved from ‘Needs Triage’ to ‘Needs More Info’.

4

Yeah I have this same issue but I think its considered normal behavior.

If you have Device A and Device B reference eachother, it pretty much creates an infinite loop.

A = import(B)
B = import(A)

Impossible ^

You can’t reference a device A to other device B, and then reference the same device B to the same device A. Imagine the compiler looping trying to get to the end of the chain and never reaching it.

5

I too recognize that circular references are a bad thing.
Just crashing and instantly closing Editor without any signal is not good for a novice Programmer.
I think the Editor should indicate what kind of problem caused the error.