title: Could not build Objective-C module 'Firebase'
body: <p>I am getting this error for <code>import Firebase</code>:</p>
  
  <blockquote>
    <p>Could not build Objective-C module 'Firebase'</p>
  </blockquote>
  
  <p>Xcode also complains about FirebaseAnalytics saying</p>
  
  <blockquote>
    <p>'FirebaseAnalytics/FirebaseAnalytics.h' file not found.</p>
  </blockquote>
  
  <p>My project used to build just fine until I updated to swift 4.</p>
  
  <p>I am using the latest version of Firebase via Cocoapods version 1.4.0 beta 2.</p>