Use BOOST_STATIC_CONSTEXPR where applicable

include/boost/container/uses_allocator.hpp

@@ -58,7 +58,7 @@ namespace container {
 //! to detect if a type should be constructed with suffix or prefix allocator arguments.
 template <class T>
 struct constructible_with_allocator_suffix
-{  static const bool value = false; };
+{  BOOST_STATIC_CONSTEXPR bool value = false; };
 
 //! <b>Remark</b>: if a specialization constructible_with_allocator_prefix<X>::value is true, indicates that T may be constructed
 //! with allocator_arg and T::allocator_type as its first two constructor arguments.
@@ -108,7 +108,7 @@ struct constructible_with_allocator_suffix
 //! to detect if a type should be constructed with suffix or prefix allocator arguments.
 template <class T>
 struct constructible_with_allocator_prefix
-{  static const bool value = false; };
+{  BOOST_STATIC_CONSTEXPR bool value = false; };
 
 #ifndef BOOST_CONTAINER_DOXYGEN_INVOKED
 
@@ -142,7 +142,7 @@ struct uses_allocator_imp
    static Allocator alloc;  // Declared but not defined
 
    public:
-   static const bool value = sizeof(test<T>(alloc)) == sizeof(yes_type);
+   BOOST_STATIC_CONSTEXPR bool value = sizeof(test<T>(alloc)) == sizeof(yes_type);
 };
 
 }  //namespace dtl {