title: Detect the the vtable offset of a specific virtual function (using Visual C++)
body: <p>Can the vtable offset of a specific virtual function be inspected?</p>
  
  <p>Why? I'd like to be able to detect unintentional binary compatibility breaks (see <a href="http://techbase.kde.org/Policies/Binary_Compatibility_Issues_With_C%2B%2B" rel="nofollow">http://techbase.kde.org/Policies/Binary_Compatibility_Issues_With_C%2B%2B</a> for what I mean by binary compatibility). </p>
  
  <p>I'm aware of the undocumented and unsupported technique of "/d1reportSingleClassLayout" (http://blogs.msdn.com/b/vcblog/archive/2007/05/17/diagnosing-hidden-odr-violations-in-visual-c-and-fixing-lnk2022.aspx), and I plan to use this technique, but I'd like to also use some simple compile time or run time checks if possible.</p>