title: Q_DECLARE_METATYPE throws missing type specifier error
body: <p>I have the following very simple class: </p>
  
  <pre><code>#ifndef SLAVECALIBRATIONGRAB
  #define SLAVECALIBRATIONGRAB
  
  #include &lt;stdint.h&gt;
  
  class SlaveCalibrationGrab{
  public:
      SlaveCalibrationGrab() : data(0) {}
      SlaveCalibrationGrab(int data_) : data(data_){}
  
      SlaveCalibrationGrab(const SlaveCalibrationGrab&amp; other){
          data = other.data;
      }
  
  
      ~SlaveCalibrationGrab(){}
  
  private:
     int data;
  };
  
  Q_DECLARE_METATYPE(SlaveCalibrationGrab);
  
  #endif
  </code></pre>
  
  <p>This throws the following error: </p>
  
  <pre><code>C4430: missing type specifier - int assumed. Note: C++ does not support default-int
  </code></pre>
  
  <p>Anybody know what I am doing wrong?</p>