Proposed resolution:

This wording is relative to N5014.

1. Modify [const.wrap.class], class template `constant_wrapper` synopsis, as indicated:

   […]
   template<cw-fixed-value X, class>
   struct constant_wrapper : cw-operators {
     static constexpr const auto & value = X.data;
   
     using type = constant_wrapper;
     using value_type = typename decltype(X)::type;
   
     […]
     constexpr operator decltype(autovalue)() const noexcept { return value; }
   };
   

Following the approval of CWG 1670 in Kona 2025, the following declaration in class template `constant_wrapper`, [const.wrap.class], is ill-formed:

constexpr operator decltype(auto)() const noexcept { return value; }