title: Custom clang method annotation
body: <p>I'd like to achieve something like the <code>__attribute__((deprecated))</code> method annotation (<code>DEPRECATED_ATTRIBUTE</code>), using a custom annotation for untested methods.</p>
  
  <p>Is it possible to create custom annotations with Xcode 4/Clang?</p>
  
  <p>What I basically want to do is have the compiler print a warning when I use a method that has a <code>UNTESTED_ATTRIBUTE</code> annotation (a method where the unit tests are still missing).</p>