I know you can use the empty interface but it hands off type checking to the runtime, which neglects the type system for a bit of generality and defeats the safety of having static typing in the first place.
You can also import the unsafe package and mess with pointers directly. Neither of these are problems.
Go strikes a nearly perfect balance between saving the programmer from accidentally shooting his foot off and getting the hell out of the way when the programmer is absolutely sure that the proper solution involves bending the rules a bit.