libavcodec/vc1dec.c:1067: error: Uninitialized Value
  The value read from uvmx_field[_] was never initialized.

libavcodec/vc1dec.c:1067:9: 
1065.         srcU = s->last_picture.f.data[1] + uvsrc_y * s->uvlinesize + uvsrc_x;
1066.         srcV = s->last_picture.f.data[2] + uvsrc_y * s->uvlinesize + uvsrc_x;
1067.         uvmx_field[i] = (uvmx_field[i] & 3) << 1;
              ^
1068.         uvmy_field[i] = (uvmy_field[i] & 3) << 1;
1069. 
