title: What does “Arg = Owned To Guaranteed” mean in Swift crash log?
body: <p>My app running perfectly without any crashes in my phone. But in some other device it get crashed with error log <strong>function signature specialization Arg[0] = Owned To Guaranteed and Exploded, Arg[1] = Owned To Guaranteed</strong> 
  How to trace the problem. Im using coredata.</p>