Ok, I have spent far far too much time on this issue trying to make a simple reproducible case with no luck so far. However, I did find a new piece to puzzle that may help UE4 devs track this elusive issue down.
In my example here, my ShouldFlip function is using a GetPlayerCharacter node and not checking it. When I run in SIE instead of PIE, there is no player, so it starts getting this error. So yellow text correctly identifies where error was while red text says it’s from DestroyActor, which is incorrect. And this misleading message is what shows up in Message Log as source of error.
Hey ,
Is Destroy Actor in BP_Monster only referencing self, or does it interact with player character at all?
only DestroyActor I believe in my BP_Monster is when it has been shot by player. Which is impossible when in SIE with no character to even shoot them. Plus I have a breakpoint on that DestroyActor, so I can see these errors scroll by but breakpoint is never hit.
DestroyActor node doesn’t actually need to be hit for an accessed none error to occur. So if Destroy Actor is trying to reference a null actor, it will drop this error. Otherwise, this is probably another example of a known issue with accessed none errors (UE-3412) not actually meaning anything.
You said error that is referencing DestroyActor is not correct. I might need to see a screenshot of BP to be sure, but my guess is that accessed none error message involving DestroyActor node is a valid runtime error because it references player character in some way (though error message maybe not particularly helpful). If yellow text helps locate issue, is there another problem you’re encountering with this?
This is a real error, it’s just in my ShouldFlip function exactly where yellow text says it should be.
I don’t believe so. To test this, I just deleted function that had DestroyActor node entirely. Now when I get error from ShouldFlip, it reports a new different location.
Again, yellow text is correct, red text says it’s from another location.
When I click link in message log, it takes me here where there is no possibility of a access none error:
Okay, yea, that is definitely UE-3412, then. I’ll go ahead an add this post and your details to that bug report, and I’ll let you know when I see any update. accessed none error’s link can be ignored in this case, as long as LogScript:Warning is giving you information you need.
Oh, sorry. Those are our bug reports, and they’re not currently public. There’s been some talk about that changing, but I don’t have a timeline for that yet. For now, we mostly post them here so that if someone asks for an update, or if it gets fixed, we can reference it easily and reply.
Just curious when you say UE-3412 is this a github issue or otherwise publicly visible web page I can view? Or some internal Epic bug queue?
Hey , I have same issue in 4.7, is this bug resolved in 4.8? I’m a bit desperate as I can’t find an error in my blueprints. Sometimes error log locate problem in an empty function which is confusing.
Not yet, but I’ve updated bug and emailed appropriate team. I’ll post here when I see any change on its status.
