diff --git a/test/function_n_test.cpp b/test/function_n_test.cpp
index 0de9202..396d4ff 100644
--- a/test/function_n_test.cpp
+++ b/test/function_n_test.cpp
@@ -536,7 +536,7 @@ test_one_arg()
   function1<string, string> id(&identity_str);
   BOOST_TEST(id("str") == "str");
 
-  function1<std::string, char*> id2(&identity_str);
+  function1<std::string, const char*> id2(&identity_str);
   BOOST_TEST(id2("foo") == "foo");
 
   add_to_obj add_to(5);
diff --git a/test/function_test.cpp b/test/function_test.cpp
index 2835a1e..976d427 100644
--- a/test/function_test.cpp
+++ b/test/function_test.cpp
@@ -536,7 +536,7 @@ test_one_arg()
   function<string, string> id(&identity_str);
   BOOST_TEST(id("str") == "str");
 
-  function<std::string, char*> id2(&identity_str);
+  function<std::string, const char*> id2(&identity_str);
   BOOST_TEST(id2("foo") == "foo");
 
   add_to_obj add_to(5);