title: Undefined symbol: _OBJC_CLASS_$_FIRApp
body: <p>I m trying to add Firebase Analytic and Firebase Crashlytics using Swift package manager here is a link of git for firebase SDK<br />
  <a href="https://github.com/firebase/firebase-ios-sdk" rel="nofollow noreferrer">https://github.com/firebase/firebase-ios-sdk</a></p>
  <p>after that I add this two line in my AppDelegate file</p>
  <blockquote>
  <p>#import &lt;FirebaseCore/FIRApp.h&gt;</p>
  </blockquote>
  <blockquote>
  <p>#import &lt;Firebase.h&gt;</p>
  </blockquote>
  <p>All fine until when I add this <code>[FIRApp configure];</code> getting error</p>
  <blockquote>
  <p>Undefined symbols for architecture arm64:
  &quot;<em>OBJC_CLASS</em>$_FIRApp&quot;, referenced from:
  objc-class-ref in HWOFAppDelegate.o
  ld: symbol(s) not found for architecture arm64
  clang: error: linker command failed with exit code 1 (use -v to see invocation)</p>
  </blockquote>
  <p>I go thought every link of stack-overflow for similar problem try every solution but nothing help me like change Other Linker Flag etc...
  Please help me..I really appreciate...I m using Xcode 12.1 with Objective-C
  here is a screenshot of error which i m getting</p>
  <p><a href="https://i.stack.imgur.com/kdhrH.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/kdhrH.png" alt="enter image description here" /></a></p>
  <p>And screenshot of added dependency</p>
  <p><a href="https://i.stack.imgur.com/MCruA.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/MCruA.png" alt="enter image description here" /></a></p>