C++ PATCH for c++/48647 (wrong common pointer type in SFINAE)

commit 8b4f0e86bd63184f63ec3ca0e6960ea9d88f90fa
Author: Jason Merrill <jason@redhat.com>
Date:   Sun May 22 01:15:13 2011 -0400

    	PR c++/48647
    	* typeck.c (composite_pointer_type_r): Return error_mark_node
    	on error in SFINAE context.

diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index 7791efc..dd1cc3b 100644
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -516,7 +516,8 @@  composite_pointer_type_r (tree t1, tree t2,
     {
       if (complain & tf_error)
 	composite_pointer_error (DK_PERMERROR, t1, t2, operation);
-
+      else
+	return error_mark_node;
       result_type = void_type_node;
     }
   result_type = cp_build_qualified_type (result_type,
@@ -527,9 +528,13 @@  composite_pointer_type_r (tree t1, tree t2,
   if (TYPE_PTR_TO_MEMBER_P (t1))
     {
       if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
-			TYPE_PTRMEM_CLASS_TYPE (t2))
-	  && (complain & tf_error))
-	composite_pointer_error (DK_PERMERROR, t1, t2, operation);
+			TYPE_PTRMEM_CLASS_TYPE (t2)))
+	{
+	  if (complain & tf_error)
+	    composite_pointer_error (DK_PERMERROR, t1, t2, operation);
+	  else
+	    return error_mark_node;
+	}
       result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
 				       result_type);
     }
diff --git a/gcc/testsuite/g++.dg/cpp0x/sfinae23.C b/gcc/testsuite/g++.dg/cpp0x/sfinae23.C
new file mode 100644
index 0000000..4e2ea88
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/sfinae23.C
@@ -0,0 +1,28 @@ 
+// PR c++/48647
+// { dg-options -std=c++0x }
+
+template< class T >
+T&& declval();
+
+template< class T, class U >
+decltype( true ? declval<T>() : declval<U>() ) test( int );
+
+template< class T, class U >
+void test( ... );
+
+
+template< class T, class U >
+struct is_same {
+  static const bool value = false;
+};
+
+template< class T >
+struct is_same<T, T> {
+  static const bool value = true;
+};
+
+#define SA(X) static_assert ((X),#X)
+
+typedef decltype( test<int*, double*>(0) ) void_expected;
+SA ((is_same<void_expected, void>::value));
+SA ((!is_same<void_expected, void*>::value));
diff --git a/gcc/testsuite/g++.dg/template/sfinae8.C b/gcc/testsuite/g++.dg/template/sfinae8.C
index 2ad68dc..5ac09c6 100644
--- a/gcc/testsuite/g++.dg/template/sfinae8.C
+++ b/gcc/testsuite/g++.dg/template/sfinae8.C
@@ -120,7 +120,7 @@  STATIC_ASSERT((!is_equality_comparable<Y, X>::value));
 STATIC_ASSERT((!is_equality_comparable<Y>::value));
 STATIC_ASSERT((is_equality_comparable<int X::*>::value));
 STATIC_ASSERT((!is_equality_comparable<int X::*, int Y::*>::value));
-STATIC_ASSERT((is_equality_comparable<int*, float*>::value));
+STATIC_ASSERT((!is_equality_comparable<int*, float*>::value));
 STATIC_ASSERT((is_equality_comparable<X*, Z*>::value));
 STATIC_ASSERT((!is_equality_comparable<X*, Y*>::value));
 
@@ -139,7 +139,7 @@  STATIC_ASSERT((!is_not_equal_comparable<Y, X>::value));
 STATIC_ASSERT((!is_not_equal_comparable<Y>::value));
 STATIC_ASSERT((is_not_equal_comparable<int X::*>::value));
 STATIC_ASSERT((!is_not_equal_comparable<int X::*, int Y::*>::value));
-STATIC_ASSERT((is_not_equal_comparable<int*, float*>::value));
+STATIC_ASSERT((!is_not_equal_comparable<int*, float*>::value));
 STATIC_ASSERT((is_not_equal_comparable<X*, Z*>::value));
 STATIC_ASSERT((!is_not_equal_comparable<X*, Y*>::value));