As everyone said above, there aren't any real dangers mixing the two. Personally I would change the order in which your taking them. Depending on your tollerence to benzos and amphetamines, 1mg of Xanax may deminish the effects of 10mg of adderall. Unless u have little tolerance to adderall and more to benzos.
Typically people use benzos while coming down off amphetamines. Relieve the uneasiness often felt during the comedown.
I certainly wouldn't worry however. Take them simultaneously if you wish.