libavcodec/motion_est_template.c:804: error: Uninitialized Value
  The value read from ymax was never initialized.

libavcodec/motion_est_template.c:804:5: 
802.     d= dmin;
803.     CHECK_CLIPPED_MV(x  , y);
804.     CHECK_CLIPPED_MV(x+1, y);
         ^
805.     CHECK_CLIPPED_MV(x, y+1);
806.     CHECK_CLIPPED_MV(x-1, y);
