title: Qt and no moc_*.cpp file
body: <p>I'm developing a simple Qt 4 app and making my own dialog. I subclassed <code>QDialog</code>, inserted the <code>Q_OBJECT</code> macro in the class declaration block, and... I get</p>
  
  <blockquote>
    <p>[Linker error] undefined reference to `vtable for MyDialog' and there is no 
    moc_MyDialog.cpp generated by the moc compiler.</p>
  </blockquote>
  
  <p>I am using Qt 4.1.3 on Windows XP and mingw. I followed the build process from the Qt-supplied build shell. I used qmake to create make files and compiled everything with a make command.</p>
  
  <p>I have other classes that subclass <code>QPushButton</code> and <code>QObject</code> respectively, but they compile OK. I can't find any differences between them and the broken one.</p>
  
  <p>There must be missing something in the broken class, but I'm unable to spot it.</p>