title: apple mach-o linker error linker command failed with exit code 1 (use -v to see invocation)
body: <p><a href="https://i.stack.imgur.com/EKI1r.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/EKI1r.png" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/pMAAm.png" rel="nofollow noreferrer">2</a>I am working with Objective C with core data, I got an error: </p>
  
  <p>Apple Mach-O Linker Error, Linker command failed with exit code 1 (use -v to see invocation)<a href="https://i.stack.imgur.com/efGqd.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/efGqd.png" alt="enter image description here"></a></p>