title: __OBJC__ equivalent for Objective-C++
body: <p>I'm compiling a .mm file (Objective-C++) for an iPhone application, and the precompiled header fails to include the base classes.</p>
  
  <p>I tracked it down to the following:</p>
  
  <pre><code>#ifdef __OBJC__
      #import &lt;Foundation/Foundation.h&gt;
      #import &lt;UIKit/UIKit.h&gt;
  #endif
  </code></pre>
  
  <p>Turns out, <code>__OBJC__</code> is undefined for mm files, whereas it is defined for standard m files.</p>
  
  <p>Is there any other flag I can use instead?</p>