diff --git a/libstdc++-v3/ChangeLog b/libstdc++-v3/ChangeLog
index a2c94e04144b..9797785e2605 100644
--- a/libstdc++-v3/ChangeLog
+++ b/libstdc++-v3/ChangeLog
@@ -1,3 +1,10 @@
+2005-04-29  Paolo Carlini  <pcarlini@suse.de>
+
+	* include/tr1/type_traits (is_convertible): Adjust according
+	to the resolution of TR1 issue 3.20.
+	* testsuite/tr1/4_metaprogramming/relationships_between_types/
+	is_convertible/is_convertible.cc: Add tests.
+
 2005-04-28  Paolo Carlini  <pcarlini@suse.de>
 	    Gabriel Dos Reis  <gdr@integrable-solutions.net>
 
diff --git a/libstdc++-v3/include/tr1/type_traits b/libstdc++-v3/include/tr1/type_traits
index 0bd05bb1198a..176a4c334004 100644
--- a/libstdc++-v3/include/tr1/type_traits
+++ b/libstdc++-v3/include/tr1/type_traits
@@ -501,7 +501,8 @@ namespace tr1
     };
 
   template<typename _From, typename _To,
-	   bool = (is_function<_To>::value || is_array<_To>::value
+	   bool = (is_void<_From>::value || is_void<_To>::value
+		   || is_function<_To>::value || is_array<_To>::value
 		   // This special case is here only to avoid warnings.		   
 		   || (is_floating_point<typename
 		       remove_reference<_From>::type>::value
@@ -515,7 +516,9 @@ namespace tr1
 
   template<typename _From, typename _To>
     struct __is_convertible_helper<_From, _To, true>
-    { static const bool __value = __is_int_or_cref<_To>::__value; };
+    { static const bool __value = (is_void<_To>::value
+				   || (__is_int_or_cref<_To>::__value
+				       && !is_void<_From>::value)); };
 
   template<typename _From, typename _To>
     struct is_convertible
diff --git a/libstdc++-v3/testsuite/tr1/4_metaprogramming/relationships_between_types/is_convertible/is_convertible.cc b/libstdc++-v3/testsuite/tr1/4_metaprogramming/relationships_between_types/is_convertible/is_convertible.cc
index 858bfda3ad1b..19b360aca8da 100644
--- a/libstdc++-v3/testsuite/tr1/4_metaprogramming/relationships_between_types/is_convertible/is_convertible.cc
+++ b/libstdc++-v3/testsuite/tr1/4_metaprogramming/relationships_between_types/is_convertible/is_convertible.cc
@@ -54,6 +54,10 @@ void test01()
   VERIFY( (test_relationship<is_convertible, DerivedType*, ClassType*>(true)) );
   VERIFY( (test_relationship<is_convertible, DerivedType&, ClassType&>(true)) );
 
+  VERIFY( (test_relationship<is_convertible, void, void>(true)) );
+  VERIFY( (test_relationship<is_convertible, int, void>(true)) );
+  VERIFY( (test_relationship<is_convertible, int[4], void>(true)) );  
+
   // Negative tests.
   VERIFY( (test_relationship<is_convertible, const int*, int*>(false)) );
   VERIFY( (test_relationship<is_convertible, int*, float*>(false)) );
@@ -69,7 +73,11 @@ void test01()
   VERIFY( (test_relationship<is_convertible, int, ClassType>(false)) );
   VERIFY( (test_relationship<is_convertible, ClassType, DerivedType>(false)) );
   VERIFY( (test_relationship<is_convertible, ClassType*, DerivedType*>(false)) );
-  VERIFY( (test_relationship<is_convertible, ClassType&, DerivedType&>(false)) );  
+  VERIFY( (test_relationship<is_convertible, ClassType&, DerivedType&>(false)) );
+
+  VERIFY( (test_relationship<is_convertible, void, int>(false)) );
+  VERIFY( (test_relationship<is_convertible, void, float>(false)) );  
+  VERIFY( (test_relationship<is_convertible, void, int(*)(int)>(false)) );  
 }
 
 int main()