title: How to fix Undefined symbol error in Xcode?
body: <p>I am developing a React-Native application, which has both an Android and iOS version.</p>
  
  <p>When working in Xcode, I have had several errors, which included duplicated files and Mach-O Linker errors.</p>
  
  <p>Right now I'm struggling with the following error.</p>
  
  <p><a href="https://file.io/vcozn4" rel="nofollow noreferrer">This is the complete log with the error.</a></p>
  
  <p>I also append some screenshots of my configuration.</p>
  
  <p><a href="https://i.stack.imgur.com/Ro0UQ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Ro0UQ.png" alt="error"></a></p>
  
  <p><a href="https://i.stack.imgur.com/UtILY.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/UtILY.png" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/95DX5.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/95DX5.png" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/BShfP.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/BShfP.png" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/oAZtq.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/oAZtq.png" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/wtW6w.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/wtW6w.png" alt="enter image description here"></a></p>