title: "parameter has incomplete type" warning
body: <p>I have this in a C file:</p>
  
  <pre><code>struct T
  {
      int foo;
  };
  </code></pre>
  
  <p>the C file has an include to an h file with those lines:</p>
  
  <pre><code>typedef struct T T;
  void listInsertFirst(T data, int key, LinkedList* ListToInsertTo);
  </code></pre>
  
  <p>the function <code>listInsertFirst</code> is the one I'm getting the warning on.  How can I fix it?</p>