libavcodec/motion_est_template.c:756: error: Uninitialized Value
  The value read from ymin was never initialized.

libavcodec/motion_est_template.c:756:12: 
754.         CHECK_MV(x2, y);
755.     }
756.     for(y2=FFMAX(y-dia_size/2+1, ymin); y2<=FFMIN(y+dia_size/2-1,ymax); y2+=2){
                ^
757.         CHECK_MV(x, y2);
758.     }
