Borland workaround. Replace 'add_const<value_type>::type with

'const value_type' in the code which computed the pointer type. Borland
did not property add const type with 'add_const'.


[SVN r27388]

include/boost/iterator/iterator_facade.hpp

@@ -107,7 +107,7 @@ namespace boost
         
         typedef typename mpl::eval_if<
             detail::iterator_writability_disabled<ValueParam,Reference>
-          , add_pointer<typename add_const<value_type>::type>
+          , add_pointer<const value_type>
           , add_pointer<value_type>
         >::type pointer;