diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index 6a8e4216307..17a134f81ac 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,14 @@
+2004-12-16  Paolo Carlini  <pcarlini@suse.de>
+
+	* include/tr1/type_traits: Implement add_const, add_volatile,
+	and add_cv.
+	* testsuite/tr1/4_metaprogramming/const_volatile_modifications/
+	add_const.cc: New.
+	* testsuite/tr1/4_metaprogramming/const_volatile_modifications/
+	add_cv.cc: Likewise.
+	* testsuite/tr1/4_metaprogramming/const_volatile_modifications/
+	add_volatile.cc: Likewise.
+
 2004-12-16  Paolo Carlini  <pcarlini@suse.de>
 
 	* include/tr1/type_traits: Implement is_function.
diff --git a/libstdc++-v3/include/tr1/type_traits b/libstdc++-v3/include/tr1/type_traits
index 0e74d3ec0a2..97008a131eb 100644
--- a/libstdc++-v3/include/tr1/type_traits
+++ b/libstdc++-v3/include/tr1/type_traits
@@ -330,13 +330,19 @@ namespace tr1
     };
   
   template<typename _Tp>
-    struct add_const;
+    struct add_const
+    { typedef _Tp const     type; };
    
   template<typename _Tp>
-    struct add_volatile;
+    struct add_volatile
+    { typedef _Tp volatile     type; };
   
   template<typename _Tp>
-    struct add_cv;
+    struct add_cv
+    {
+      typedef typename
+      add_const<typename add_volatile<_Tp>::type>::type     type;
+    };
 
   /// @brief  reference modifications [4.7.2].
   template<typename _Tp>
diff --git a/libstdc++-v3/testsuite/tr1/4_metaprogramming/const_volatile_modifications/add_const.cc b/libstdc++-v3/testsuite/tr1/4_metaprogramming/const_volatile_modifications/add_const.cc
new file mode 100644
index 00000000000..83394c4de13
--- /dev/null
+++ b/libstdc++-v3/testsuite/tr1/4_metaprogramming/const_volatile_modifications/add_const.cc
@@ -0,0 +1,54 @@
+// 2004-12-16  Paolo Carlini  <pcarlini@suse.de>
+//
+// Copyright (C) 2004 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING.  If not, write to the Free
+// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+// USA.
+
+// 4.7.1 Const-volatile modifications
+
+#include <tr1/type_traits>
+#include <testsuite_hooks.h>
+#include <testsuite_tr1.h>
+
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  using std::tr1::add_const;
+  using std::tr1::is_same;
+  using namespace __gnu_test;
+
+  VERIFY( (is_same<add_const<int>::type, const int>::value) );
+  VERIFY( (is_same<add_const<volatile int>::type, const volatile int>::value) );
+  VERIFY( (is_same<add_const<int*>::type, int* const>::value) );
+  VERIFY( (is_same<add_const<int&>::type, int&>::value) );
+  VERIFY( (is_same<add_const<int (int)>::type, int (int)>::value) );
+  VERIFY( (is_same<add_const<const int>::type, const int>::value) );
+  VERIFY( (is_same<add_const<ClassType>::type, const ClassType>::value) );
+  VERIFY( (is_same<add_const<volatile ClassType>::type,
+	   const volatile ClassType>::value) );
+  VERIFY( (is_same<add_const<ClassType*>::type, ClassType* const>::value) );
+  VERIFY( (is_same<add_const<ClassType&>::type, ClassType&>::value) );
+  VERIFY( (is_same<add_const<ClassType (ClassType)>::type,
+	   ClassType (ClassType)>::value) );
+  VERIFY( (is_same<add_const<const ClassType>::type, const ClassType>::value) );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/tr1/4_metaprogramming/const_volatile_modifications/add_cv.cc b/libstdc++-v3/testsuite/tr1/4_metaprogramming/const_volatile_modifications/add_cv.cc
new file mode 100644
index 00000000000..02d6460d6cd
--- /dev/null
+++ b/libstdc++-v3/testsuite/tr1/4_metaprogramming/const_volatile_modifications/add_cv.cc
@@ -0,0 +1,57 @@
+// 2004-12-16  Paolo Carlini  <pcarlini@suse.de>
+//
+// Copyright (C) 2004 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING.  If not, write to the Free
+// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+// USA.
+
+// 4.7.1 Const-volatile modifications
+
+#include <tr1/type_traits>
+#include <testsuite_hooks.h>
+#include <testsuite_tr1.h>
+
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  using std::tr1::add_cv;
+  using std::tr1::is_same;
+  using namespace __gnu_test;
+
+  VERIFY( (is_same<add_cv<int>::type, const volatile int>::value) );
+  VERIFY( (is_same<add_cv<const int>::type, const volatile int>::value) );
+  VERIFY( (is_same<add_cv<int*>::type, int* const volatile>::value) );
+  VERIFY( (is_same<add_cv<int&>::type, int&>::value) );
+  VERIFY( (is_same<add_cv<int (int)>::type, int (int)>::value) );
+  VERIFY( (is_same<add_cv<const volatile int>::type,
+	   const volatile int>::value) );
+  VERIFY( (is_same<add_cv<ClassType>::type, const volatile ClassType>::value) );
+  VERIFY( (is_same<add_cv<volatile ClassType>::type,
+	   const volatile ClassType>::value) );
+  VERIFY( (is_same<add_cv<ClassType*>::type,
+	   ClassType* const volatile>::value) );
+  VERIFY( (is_same<add_cv<ClassType&>::type, ClassType&>::value) );
+  VERIFY( (is_same<add_cv<ClassType (ClassType)>::type,
+	   ClassType (ClassType)>::value) );
+  VERIFY( (is_same<add_cv<const volatile ClassType>::type,
+	   const volatile ClassType>::value) );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}
diff --git a/libstdc++-v3/testsuite/tr1/4_metaprogramming/const_volatile_modifications/add_volatile.cc b/libstdc++-v3/testsuite/tr1/4_metaprogramming/const_volatile_modifications/add_volatile.cc
new file mode 100644
index 00000000000..09a9ef58544
--- /dev/null
+++ b/libstdc++-v3/testsuite/tr1/4_metaprogramming/const_volatile_modifications/add_volatile.cc
@@ -0,0 +1,56 @@
+// 2004-12-16  Paolo Carlini  <pcarlini@suse.de>
+//
+// Copyright (C) 2004 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2, or (at your option)
+// any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING.  If not, write to the Free
+// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+// USA.
+
+// 4.7.1 Const-volatile modifications
+
+#include <tr1/type_traits>
+#include <testsuite_hooks.h>
+#include <testsuite_tr1.h>
+
+void test01()
+{
+  bool test __attribute__((unused)) = true;
+  using std::tr1::add_volatile;
+  using std::tr1::is_same;
+  using namespace __gnu_test;
+
+  VERIFY( (is_same<add_volatile<int>::type, volatile int>::value) );
+  VERIFY( (is_same<add_volatile<const int>::type, const volatile int>::value) );
+  VERIFY( (is_same<add_volatile<int*>::type, int* volatile>::value) );
+  VERIFY( (is_same<add_volatile<int&>::type, int&>::value) );
+  VERIFY( (is_same<add_volatile<int (int)>::type, int (int)>::value) );
+  VERIFY( (is_same<add_volatile<volatile int>::type, volatile int>::value) );
+  VERIFY( (is_same<add_volatile<ClassType>::type, volatile ClassType>::value) );
+  VERIFY( (is_same<add_volatile<const ClassType>::type,
+	   const volatile ClassType>::value) );
+  VERIFY( (is_same<add_volatile<ClassType*>::type,
+	   ClassType* volatile>::value) );
+  VERIFY( (is_same<add_volatile<ClassType&>::type, ClassType&>::value) );
+  VERIFY( (is_same<add_volatile<ClassType (ClassType)>::type,
+	   ClassType (ClassType)>::value) );
+  VERIFY( (is_same<add_volatile<volatile ClassType>::type,
+	   volatile ClassType>::value) );
+}
+
+int main()
+{
+  test01();
+  return 0;
+}