Use boost::addressof and update docs

include/boost/implicit_cast.hpp

@@ -2,8 +2,9 @@
 // Distributed under the Boost Software License, Version 1.0. (See
 // accompanying file LICENSE_1_0.txt or copy at
 // http://www.boost.org/LICENSE_1_0.txt)
-#ifndef IMPLICIT_CAST_DWA200356_HPP
-# define IMPLICIT_CAST_DWA200356_HPP
+
+#ifndef BOOST_IMPLICIT_CAST_DWA200356_HPP
+#define BOOST_IMPLICIT_CAST_DWA200356_HPP
 
 namespace boost {
 
@@ -26,11 +27,7 @@ inline T implicit_cast (typename boost::detail::icast_identity<T>::type x) {
     return x;
 }
 
-// incomplete return type now is here
-//template <typename T>
-//void implicit_cast (...);
-
 } // namespace boost
 
 
-#endif // IMPLICIT_CAST_DWA200356_HPP
+#endif // BOOST_IMPLICIT_CAST_DWA200356_HPP

include/boost/polymorphic_cast.hpp

@@ -50,17 +50,20 @@
 #define BOOST_POLYMORPHIC_CAST_HPP
 
 # include <boost/config.hpp>
-# include <boost/assert.hpp>
-# include <boost/throw_exception.hpp>
-# include <boost/type_traits/is_reference.hpp> 
-# include <boost/type_traits/remove_reference.hpp>
-# include <boost/utility/enable_if.hpp>
-# include <typeinfo>
 
 #ifdef BOOST_HAS_PRAGMA_ONCE
 #   pragma once
 #endif
 
+# include <boost/assert.hpp>
+# include <boost/core/addressof.hpp>
+# include <boost/core/enable_if.hpp>
+# include <boost/throw_exception.hpp>
+# include <boost/type_traits/is_reference.hpp> 
+# include <boost/type_traits/remove_reference.hpp>
+
+# include <typeinfo>
+
 namespace boost
 {
 //  See the documentation for descriptions of how to choose between
@@ -108,10 +111,14 @@ namespace boost
     //  Contributed by Julien Delacroix
 
     template <class Target, class Source>
-    inline typename boost::enable_if_c<boost::is_reference<Target>::value, Target>::type polymorphic_downcast(Source &x)
+    inline typename boost::enable_if_c<
+        boost::is_reference<Target>::value, Target
+    >::type polymorphic_downcast(Source& x)
     {
-        BOOST_ASSERT(dynamic_cast<typename boost::remove_reference<Target>::type *>(&x) == &x);
-        return static_cast<Target>(x);
+        typedef typename boost::remove_reference<Target>::type* target_pointer_type;
+        return *boost::polymorphic_downcast<target_pointer_type>(
+            boost::addressof(x)
+        );
     }
 
 } // namespace boost