Ticket #7577: base_from_member.patch

(a) d:\boost_1_51_0\boost\utility\base_from_member.hpp vs. (b) D:\Documents\Visual

@@ -77 +77 @@
 
 };  // boost::base_from_member
 
+
+// Specialization to deal with references correctly. The general 
+// template constructors take their arguments by value, resulting 
+// in a dangling reference.
+
+// Contributed by Agustín K-ballo Bergé
+
+template < typename MemberType, int UniqueId >
+class base_from_member< MemberType&, UniqueId >
+{
+protected:
+    MemberType&  member;
+
+    explicit base_from_member( MemberType& x )
+        : member( x )
+        {}
+
+};  // boost::base_from_member
+
 }  // namespace boost