title: MyClass is unavailable: cannot find Swift declaration for this class - Release Build Only
body: <p>I am getting the following error:</p>
  
  <p>MyClass is unavailable: cannot find Swift declaration for this class</p>
  
  <p>but I only get it when doing a release build in Xcode...Debug works fine.</p>
  
  <p>Anyone know what's up? I'm running 6.3</p>