UE4 editor crash due to missing pose asset

I create an evaluate pose node in animation blueprint. Then convert it to get pose by name node. I also create a pose asset variable, then hook up like the graph.

If I leave the pose asset default value to None. Then compile the blueprint will cause UE editor crash. Even just open the blueprint still causing crash too.
The crash log is
[link text][2]

If I set a default value to the pose asset variable, then it works fine.
I’m wondering if there is a way to check if the pose asset is valid then just show some error message instead of simply crashing UE editor