* name-lookup.c (ambiguous_decl): Fix case when new->value is hidden.
	(select_decl): Remove function.
	(unqualified_namespace_lookup): Populate binding by calling
	ambiguous_decl.  Remove select_decl call.
	(lookup_qualified_name): Remove select_decl call.
	* decl.c (lookup_and_check_tag): Check for ambiguous references.
	* parser.c (cp_parser_elaborated_type_specifier): Skip redundant error
	generation when name lookup is ambiguous.

	* g++.dg/lookup/using16.C: New test.
	* g++.dg/lookup/using17.C: New test.

From-SVN: r126177