re PR c++/13507 (spurious printf format warning)

cp:
	PR c++/13507
	* decl.c (duplicate_decls): Use build_type_attribute_variant to
	merge attributes.
testsuite:
	PR c++/13507
	* g++.dg/ext/attrib11.C: New test.

From-SVN: r75229

gcc/cp/ChangeLog

 2003-12-30  Nathan Sidwell  <nathan@codesourcery.com>
 
+	PR c++/13507
+	* decl.c (duplicate_decls): Use build_type_attribute_variant to
+	merge attributes.
+
 	PR c++/13494
 	* tree.c (build_cplus_array_type_1): Only build a minimal array
 	type for dependent types or domains.

gcc/cp/decl.c

@@ -1262,10 +1262,12 @@ duplicate_decls (tree newdecl, tree olddecl)
 	 for anticipated built-ins, for exception lists, etc...  */
       else if (DECL_ANTICIPATED (olddecl))
 	{
-	  TYPE_ATTRIBUTES (TREE_TYPE (newdecl))
-	    = (*targetm.merge_type_attributes) (TREE_TYPE (olddecl),
-						TREE_TYPE (newdecl));
-	  TREE_TYPE (olddecl) = TREE_TYPE (newdecl);
+	  tree type = TREE_TYPE (newdecl);
+	  tree attribs = (*targetm.merge_type_attributes)
+	    (TREE_TYPE (olddecl), type);
+
+	  type = build_type_attribute_variant (type, attribs);
+	  TREE_TYPE (newdecl) = TREE_TYPE (olddecl) = type;
 	}
 
       /* Whether or not the builtin can throw exceptions has no

gcc/testsuite/ChangeLog

 2003-12-30  Nathan Sidwell  <nathan@codesourcery.com>
 
+	PR c++/13507
+	* g++.dg/ext/attrib11.C: New test.
+
 	PR c++/13494
 	* g++.dg/template/array2-1.C: New test.
 	* g++.dg/template/array2-2.C: New test.

gcc/testsuite/g++.dg/ext/attrib11.C

+// { dg-do compile }
+// { dg-options "-Wall" }
+
+// Copyright (C) 2003 Free Software Foundation, Inc.
+// Contributed by Nathan Sidwell 30 Dec 2003 <nathan@codesourcery.com>
+
+
+// PR c++/13507, spurious warning due to attribute clobbering
+extern "C" {
+  extern int printf (__const char *__restrict __format, ...) throw ();
+  extern int scanf (__const char *__restrict __format, ...) throw ();
+}
+
+void foo(unsigned int x)
+{
+  printf ("%d\n", x);
+}