GVReticle warning

Hi! im getting a warning when i try to build a project for android using GoogleVR like this
"Assets/GoogleVR/Scripts/UI/GvrReticle.cs(68,25): warning CS0252: Possible unintended reference comparison. Consider casting the left side expression to type `GvrReticle' to get value comparison" and the buld process stucks!

What it means? thank you!