libswscale/swscale.c:1276: error: Uninitialized Value
  The value read from A was never initialized.

libswscale/swscale.c:1276:23: 
1274.             dest[1] = G >> 22;
1275.             dest[2] = R >> 22;
1276.             dest[3] = hasAlpha ? A : 255;
                            ^
1277.             break;
1278.         }
