re PR c++/21087 (ICE in do_nonmember_using_decl)

gcc/cp/ChangeLog:
PR c++/21087
* name-lookup.c (push_overloaded_decl): Do not overload with
non-duplicate anticipated built-in.
gcc/testsuite/ChangeLog:
PR c++/21087
* g++.dg/lookup/builtin2.C: New test.

From-SVN: r98570

gcc/cp/ChangeLog

+2005-04-22  Alexandre Oliva  <aoliva@redhat.com>
+
+	PR c++/21087
+	* name-lookup.c (push_overloaded_decl): Do not overload with
+	non-duplicate anticipated built-in.
+
 2005-04-21  Kazu Hirata  <kazu@cs.umass.edu>
 
 	* cp-tree.h (THROW_NAME, AUTO_VTABLE_NAME, AUTO_TEMP_FORMAT,

gcc/cp/name-lookup.c

@@ -1883,6 +1883,13 @@ push_overloaded_decl (tree decl, int flags)
 	      if (duplicate_decls (decl, fn) == fn)
 		POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, fn);
 	    }
+
+	  /* We don't overload implicit built-ins.  duplicate_decls()
+	     may fail to merge the decls if the new decl is e.g. a
+	     template function.  */
+	  if (TREE_CODE (old) == FUNCTION_DECL
+	      && DECL_ANTICIPATED (old))
+	    old = NULL;
 	}
       else if (old == error_mark_node)
 	/* Ignore the undefined symbol marker.  */

gcc/testsuite/ChangeLog

+2005-04-22  Alexandre Oliva  <aoliva@redhat.com>
+
+	PR c++/21087
+	* g++.dg/lookup/builtin2.C: New test.
+
 2005-04-22  Joseph S. Myers  <joseph@codesourcery.com>
 
 	* gcc.dg/weak/weak-13.c: New test.

gcc/testsuite/g++.dg/lookup/builtin2.C

+/* { dg-do compile } */
+
+/* PR c++/21087 */
+
+/* We used to overload the template function with the built-in
+   declaration, instead of replacing it as we should, and then barf at
+   the using decl because of a test that none of the overload set
+   members were anticipated built-ins.  */
+
+extern "C" signed int toupper(signed int __c) throw();
+namespace std
+{
+  template< typename a > a toupper(a,int){}
+  using ::toupper;
+}
+
+int f () {
+  std::toupper((signed int)'a');
+}