Index: boost/concept/detail/msvc.hpp
===================================================================
--- boost/concept/detail/msvc.hpp	(revision 527)
+++ boost/concept/detail/msvc.hpp	(revision 528)
@@ -20,6 +20,9 @@
     virtual void failed(Model* x)
     {
         x->~Model();
+#if BOOST_WORKAROUND(BOOST_MSVC, == 1500)
+        ignore_unused_variable_warning(x);
+#endif
     }
 };
   
Index: boost/concept_check.hpp
===================================================================
--- boost/concept_check.hpp	(revision 527)
+++ boost/concept_check.hpp	(revision 528)
@@ -144,6 +144,8 @@
     void const_constraints(const TT& b) {
 #if !defined(_ITERATOR_) // back_insert_iterator broken for VC++ STL
       a = b;              // const required for argument to assignment
+#else
+    ignore_unused_variable_warning(b);
 #endif
     }
    private: