libavcodec/motion_est_template.c:806: error: Uninitialized Value
  The value read from ymax was never initialized.

libavcodec/motion_est_template.c:806:5: 
804.     CHECK_CLIPPED_MV(x+1, y);
805.     CHECK_CLIPPED_MV(x, y+1);
806.     CHECK_CLIPPED_MV(x-1, y);
         ^
807.     CHECK_CLIPPED_MV(x, y-1);
808.     best[0]= x;
