title: autorelease not allowing to compile code
body: <p>I am trying to convert an old code to an ARC code. 
  However, i am getting a build error at the following line</p>
  
  <pre><code>[[token retain] autorelease];
  </code></pre>
  
  <p>I get 3 errors in the following order: </p>
  
  <p>-'autorelease' is unavailable: not available in automatic reference counting mode</p>
  
  <p>-[rewriter] it is not safe to remove an unused 'autorelease' message; its receiver may be destroyed immediately </p>
  
  <p>-ARC forbids explicit message send of 'autorelease'</p>
  
  <p>If i remove this particular line, then the code compiles correctly</p>