I am using the Xcode 8.0 GM. I created a default single-view app with my deployment target set to 9.0.
In my Podfile I\'m targeting the bleeding edge Swift 3 branch:
I had the same issue, but I uninstalled cocoapods, uninstalled alamofire, then updated my cocoa pods to 1.1.0.beta.2, then used the swift3-rebased branch of Alamofire in my pod file
pod 'Alamofire',
    :git => 'https://github.com/Alamofire/Alamofire.git',
    :branch => 'swift3-rebased'
opened my Project.xcworkspace file and all the compiling errors for Alamofire were gone.