libswscale/swscale.c:1048: error: Uninitialized Value
  The value read from A1 was never initialized.

libswscale/swscale.c:1048:46: 
1046.         b =  c->table_bU[U];
1047. 
1048.         yuv2rgb_write(dest, i, Y1, Y2, U, V, hasAlpha ? A1 : 0, hasAlpha ? A2 : 0,
                                                   ^
1049.                       r, g, b, y, target, hasAlpha);
1050.     }
