Index: boost/algorithm/string/detail/finder.hpp
===================================================================
--- boost/algorithm/string/detail/finder.hpp	(revision 84132)
+++ boost/algorithm/string/detail/finder.hpp	(working copy)
@@ -142,7 +142,7 @@
                     ForwardIteratorT End,
                     std::forward_iterator_tag ) const
                 {
-                    typedef ForwardIteratorT input_iterator_type;
+                    //typedef ForwardIteratorT input_iterator_type; // not used
                     typedef iterator_range<ForwardIteratorT> result_type;
 
                     first_finder_type first_finder(
@@ -263,7 +263,7 @@
                     ForwardIteratorT End,
                     unsigned int N) const
                 {
-                    typedef ForwardIteratorT input_iterator_type;
+                    //typedef ForwardIteratorT input_iterator_type; //not used
                     typedef iterator_range<ForwardIteratorT> result_type;
 
                     // Sanity check
@@ -298,7 +298,7 @@
                     ForwardIteratorT End,
                     unsigned int N) const
                 {
-                    typedef ForwardIteratorT input_iterator_type;
+                    //typedef ForwardIteratorT input_iterator_type; // not used
                     typedef iterator_range<ForwardIteratorT> result_type;
 
                     // Sanity check
@@ -362,7 +362,7 @@
                 unsigned int N,
                 std::random_access_iterator_tag )
             {
-                typedef ForwardIteratorT input_iterator_type;
+                //typedef ForwardIteratorT input_iterator_type; // not used
                 typedef iterator_range<ForwardIteratorT> result_type;
 
                 if ( (End<=Begin) || ( static_cast<unsigned int>(End-Begin) < N ) )
@@ -436,7 +436,7 @@
                 unsigned int N,
                 std::random_access_iterator_tag )
             {
-                typedef ForwardIteratorT input_iterator_type;
+                //typedef ForwardIteratorT input_iterator_type; // not used
                 typedef iterator_range<ForwardIteratorT> result_type;
 
                 if ( (End<=Begin) || ( static_cast<unsigned int>(End-Begin) < N ) )
Index: boost/lexical_cast.hpp
===================================================================
--- boost/lexical_cast.hpp	(revision 84132)
+++ boost/lexical_cast.hpp	(working copy)
@@ -880,7 +880,7 @@
 #ifndef BOOST_NO_LIMITS_COMPILE_TIME_CONSTANTS
             BOOST_STATIC_ASSERT(!std::numeric_limits<T>::is_signed);
 #endif
-            typedef typename Traits::int_type int_type;
+            //typedef typename Traits::int_type int_type; // not used
             CharT const czero = lcast_char_constants<CharT>::zero;
             --end;
             value = 0;
Index: boost/concept/detail/general.hpp
===================================================================
--- boost/concept/detail/general.hpp	(revision 84132)
+++ boost/concept/detail/general.hpp	(working copy)
@@ -12,6 +12,14 @@
 #  include <boost/mpl/if.hpp>
 # endif
 
+//
+// If the compiler warns about unused typedefs then enable this:
+//
+#if defined(__GNUC__) && ((__GNUC__ > 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 7)))
+#  define BOOST_CONCEPT_ASSERT_UNUSED_ATTRIBUTE __attribute__((unused))
+#else
+#  define BOOST_CONCEPT_ASSERT_UNUSED_ATTRIBUTE
+#endif
 // This implementation works on Comeau and GCC, all the way back to
 // 2.95
 namespace boost { namespace concepts {
@@ -68,7 +76,7 @@
 #  define BOOST_CONCEPT_ASSERT_FN( ModelFnPtr )             \
     typedef ::boost::concepts::detail::instantiate<          \
     &::boost::concepts::requirement_<ModelFnPtr>::failed>    \
-      BOOST_PP_CAT(boost_concept_check,__LINE__)
+      BOOST_PP_CAT(boost_concept_check,__LINE__) BOOST_CONCEPT_ASSERT_UNUSED_ATTRIBUTE
 
 }}