title: waf : passing compiler flags to qt's moc
body: <p>I my trying to run a project using <code>waf</code> which uses <code>boost</code> library . To overcome a <a href="https://bugreports.qt-project.org/browse/QTBUG-22829" rel="nofollow">problem</a> I need to pass and <code>-DBOOST_TT_HAS_OPERATOR_HPP_INCLUDED</code> argument to <code>MOC</code>. I tried doing so in the <code>wscript</code> as </p>
  
  <pre><code>   bld(features ='cxx',
         source   ='GSTEngine.cpp',
         target   = 'GSTEngine.o',
         includes = qtinc+gstinc+taginc,use=['BOOST'],
         uselib   = qtlibs,
         cxxflags = ['-DQT_NO_KEYWORDS','-DBOOST_TT_HAS_OPERATOR_HPP_INCLUDED'])
  </code></pre>
  
  <p>but it failed. How to pass argument to <code>MOC</code> using <code>waf</code>?</p>