[PR c++/71251] check tmpl parms in template using decl

Check that template using decls have the correct number of parm lists.

for  gcc/cp/ChangeLog

	PR c++/71251
	* parser.c (cp_parser_alias_declaration): Call
	parser_check_template_parameters.

for  gcc/testsuite/ChangeLog

	PR c++/71251
	* g++.dg/cpp0x/pr71251.C: New.

From-SVN: r258793

gcc/cp/ChangeLog

-2018-03-22  Alexandre Oliva <aoliva@redhat.com>
+2018-03-23  Alexandre Oliva <aoliva@redhat.com>
+
+	PR c++/71251
+	* parser.c (cp_parser_alias_declaration): Call
+	parser_check_template_parameters.
 
 	PR c++/84789
 	* pt.c (resolve_typename_type): Drop assert that stopped

gcc/cp/parser.c

@@ -18965,6 +18965,13 @@ cp_parser_alias_declaration (cp_parser* parser)
 			       ds_alias,
 			       using_token);
 
+  if (parser->num_template_parameter_lists
+      && !cp_parser_check_template_parameters (parser,
+					       /*num_templates=*/0,
+					       id_location,
+					       /*declarator=*/NULL))
+    return error_mark_node;
+
   declarator = make_id_declarator (NULL_TREE, id, sfk_none);
   declarator->id_loc = id_location;
 

gcc/testsuite/ChangeLog

-2018-03-22  Alexandre Oliva <aoliva@redhat.com>
+2018-03-23  Alexandre Oliva <aoliva@redhat.com>
+
+	PR c++/71251
+	* g++.dg/cpp0x/pr71251.C: New.
 
 	PR c++/84789
 	* g++.dg/template/pr84789.C: New.

gcc/testsuite/g++.dg/cpp0x/pr71251.C

+// { dg-do compile { target c++11 } }
+
+template<int,int> template<typename>
+using U = void; // { dg-error "too many" }
+
+template<typename>
+using V = void;
+
+template<typename> struct X {
+  template<typename> template<typename>
+  using U = void; // { dg-error "too many" }
+
+  template<typename>
+  using V = void;
+};