title: error while loading face cascades
body: <p>I am trying to do face detection in opencv, but every time i try to load cascade classifier it gives me following error:</p>
  
  <p><code>error LNK2019: unresolved external symbol "public: virtual __thiscall cv::CascadeClassifier::~CascadeClassifier(void)" (??1CascadeClassifier@cv@@UAE@XZ) referenced in function _main</code></p>
  
  <p>I don't even understand what it is,can anyone please help me?</p>
  
  <pre><code>#include "conio.h"
  #include&lt;math.h&gt;
  #include "opencv/cvaux.hpp"
  #include "opencv2/core/core.hpp"
  #include "opencv2/calib3d/calib3d.hpp"
  #include "opencv2/imgproc/imgproc.hpp"
  #include "opencv2/highgui/highgui.hpp"
  #include "opencv2/contrib/contrib.hpp"
  #include"opencv2/objdetect/objdetect.hpp"
  #include&lt;vector&gt;
  
  using namespace cv;
  using namespace std; 
  
  int main()
  {
      CascadeClassifier face_cascade,eye_cascade;
      if(!face_cascade.load("D:\\OpenCV2.3\\opencv\\data\\haarcascades\\haarcascade_frontalface_alt2.xml"))
      {
          printf("\nerror loading face_cascade\n");
          return -1;
      }
  
      if(!eye_cascade.load("D:\\OpenCV2.3\\opencv\\data\\haarcascades\\haarcascade_eye.xml"))
      {
          printf("\nerror loading eye_cascade\n");
          return -1;
      }
      return 0;
  }
  </code></pre>