libswscale/output.c:1339: error: Uninitialized Value
  The value read from A was never initialized.

libswscale/output.c:1339:17: 
1337.             dest[2][i] = R >> 22;
1338.             if (hasAlpha)
1339.                 dest[3][i] = A;
                      ^
1340.         }
1341.     }
