Index: join.hpp
===================================================================
--- join.hpp	(revision 77364)
+++ join.hpp	(working copy)
@@ -65,8 +65,8 @@
 joined_range<const SinglePassRange1, const SinglePassRange2>
 join(const SinglePassRange1& r1, const SinglePassRange2& r2)
 {
-    BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<SinglePassRange1> ));
-    BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<SinglePassRange2> ));
+    BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<const SinglePassRange1> ));
+    BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<const SinglePassRange2> ));
 
     return joined_range<const SinglePassRange1, const SinglePassRange2>(r1, r2);
 }