title: Warning C4099: type name first seen using 'class' now seen using 'struct' (MS VS 2k8)
body: <p>Is this warning anything to worry about? I've read that it can cause erratic behaviour?</p>
  
  <p>It's an example I'm trying to compile, could someone explain to me why the author declares the object as a class but then typedef's it to a structure? Is it perfectly normal to do so if the class is <a href="http://en.wikipedia.org/w/index.php?title=Plain_old_data&amp;redirect=no" rel="noreferrer">POD</a>?</p>
  
  <p>Thanks.</p>