PR c++/78690 - ICE with using and global type with same name

	* pt.c (type_dependent_object_expression_p): True for
	IDENTIFIER_NODE.

From-SVN: r245549

gcc/cp/ChangeLog

 2017-02-17  Jason Merrill  <jason@redhat.com>
 
+	PR c++/78690 - ICE with using and global type with same name
+	* pt.c (type_dependent_object_expression_p): True for
+	IDENTIFIER_NODE.
+
 	PR c++/79549 - C++17 ICE with non-type auto template parameter pack
 	* pt.c (convert_template_argument): Just return an auto arg pack.
 	(tsubst_template_args): Don't tsubst an auto pack type.

gcc/cp/pt.c

@@ -23932,6 +23932,10 @@ type_dependent_expression_p (tree expression)
 bool
 type_dependent_object_expression_p (tree object)
 {
+  /* An IDENTIFIER_NODE can sometimes have a TREE_TYPE, but it's still
+     dependent.  */
+  if (TREE_CODE (object) == IDENTIFIER_NODE)
+    return true;
   tree scope = TREE_TYPE (object);
   return (!scope || dependent_scope_p (scope));
 }

gcc/testsuite/g++.dg/template/dependent-scope1.C

+// PR c++/78690
+
+struct C;
+
+template <typename T>
+struct A
+{
+  struct C { static void bar (); };
+};
+
+template <typename T>
+struct B
+{
+  using A<T>::C;
+  void
+  foo () { C.bar (); }
+};