Proposed resolution:

This wording is relative to N4659.

1. Change [variant.syn], header <variant> synopsis, as follows:

   […]
   // [variant.traits], allocator-related traits
   template <class T, class Alloc> struct uses_allocator;
   template <class... Types, class Alloc> struct uses_allocator<variant<Types...>, Alloc>;
   

2. Change [variant.variant], class template variant synopsis, as follows:

   […]
   // allocator-extended constructors
   template <class Alloc>
     variant(allocator_arg_t, const Alloc&);
   template <class Alloc>
     variant(allocator_arg_t, const Alloc&, const variant&);
   template <class Alloc>
     variant(allocator_arg_t, const Alloc&, variant&&);
   template <class Alloc, class T>
     variant(allocator_arg_t, const Alloc&, T&&);
   template <class Alloc, class T, class... Args>
     variant(allocator_arg_t, const Alloc&, in_place_type_t<T>, Args&&...);
   template <class Alloc, class T, class U, class... Args>
     variant(allocator_arg_t, const Alloc&, in_place_type_t<T>,
             initializer_list<U>, Args&&...);
   template <class Alloc, size_t I, class... Args>
     variant(allocator_arg_t, const Alloc&, in_place_index_t<I>, Args&&...);
   template <class Alloc, size_t I, class U, class... Args>
     variant(allocator_arg_t, const Alloc&, in_place_index_t<I>,
             initializer_list<U>, Args&&...);
   

3. Modify [variant.ctor] as indicated:

   // allocator-extended constructors
   template <class Alloc>
     variant(allocator_arg_t, const Alloc& a);
   template <class Alloc>
     variant(allocator_arg_t, const Alloc& a, const variant& v);
   template <class Alloc>
     variant(allocator_arg_t, const Alloc& a, variant&& v);
   template <class Alloc, class T>
     variant(allocator_arg_t, const Alloc& a, T&& t);
   template <class Alloc, class T, class... Args>
     variant(allocator_arg_t, const Alloc& a, in_place_type_t<T>, Args&&... args);
   template <class Alloc, class T, class U, class... Args>
     variant(allocator_arg_t, const Alloc& a, in_place_type_t<T>,
             initializer_list<U> il, Args&&... args);
   template <class Alloc, size_t I, class... Args>
     variant(allocator_arg_t, const Alloc& a, in_place_index_t<I>, Args&&... args);
   template <class Alloc, size_t I, class U, class... Args>
     variant(allocator_arg_t, const Alloc& a, in_place_index_t<I>,
             initializer_list<U> il, Args&&... args);
   

   -34- Requires: Alloc shall meet the requirements for an Allocator ([allocator.requirements]).

   -35- Effects: Equivalent to the preceding constructors except that the contained value is constructed with uses-allocator construction ([allocator.uses.construction]).

4. Modify [variant.traits] as indicated:

   template <class... Types, class Alloc>
   struct uses_allocator<variant<Types...>, Alloc> : true_type { };
   

   -1- Requires: Alloc shall be an Allocator ([allocator.requirements]).

   -2- [Note: Specialization of this trait informs other library components that variant can be constructed with an allocator, even though it does not have a nested allocator_type. — end note]