Hi,
I create an interface function that has array as input and implement it in an UMG. Then call the interface function as event and the following note appears: No value will be returned by reference.
Here is a screenshot.
I’ve searched on other forums and I’ve found that a similar problem was already fixed (Unreal Engine Issues and Bug Tracker (UE-20613)).
But now it shows up on interface event calls.
Hi zaksi,
Thank you for the report.
The bug report you referenced was fixed in 4.11 and I just verified that it is still fixed as of 4.15. However, I believe you are right that they are related.
I was able to reproduce the issue you described above with Blueprint Interface functions. So I’ve created JIRA UE-42333 and our developers will be investigating further. Follow that link to monitor it’s status.
Cheers,
TJ
i have the same issue but then with event dispatcher 
This issue still exists in 4.17. It is problematic for us because we treat warnings as errors in our build process
I can confirm that the issue still persist in UE 4.17
Came across this issue in 4.19 for an array of a specific actor blueprint.
Came across this issue in 4.20 for an array of a specific actor blueprint.
Came across this issue in 4.21 for an array of a specific actor and gamemode blueprint.
Please fix this My packaged project, crashes because of this, when using steam
Now when i create an array in event dispatcher and try to call/assign it to function i can see the same message on 4.21.2 FIX THIS EPIC PLEASE!
Can confirm this is still happening in 4.21.2 
This bug is open in Engine Ver 4.22.2 please re-open the JIRA ticket, claimed fix is not correct and this issue is severe.
This is still a bug in 4.25.4
Me the same
