title: Extern array of structs
body: <p>I have a global array of structure declared as </p>
  
  <pre><code>struct _links link[255][255][255];
  </code></pre>
  
  <p>in my main.c. This array of structures is also used in another file, action.c, and I tried to declare it in action.c as an extern, i.e.</p>
  
  <pre><code>extern struct _links link[255][255][255];
  </code></pre>
  
  <p>However, I got the error message "array type has incomplete element type". I don't understand what that means. How can I resolve this problem?</p>
  
  <p>Thank you.</p>