Proposed resolution:

This wording is relative to N3936.

1. Change [util.smartptr.shared.const] around p33 as indicated:

   template <class Y, class D> shared_ptr(unique_ptr<Y, D>&& r);
   

   -?- Remark: This constructor shall not participate in overload resolution unless unique_ptr<Y, D>::pointer is convertible to T*.

   -33- Effects: Equivalent to shared_ptr(r.release(), r.get_deleter()) when D is not a reference type, otherwise shared_ptr(r.release(), ref(r.get_deleter())).