PR c++/85731 - wrong error with qualified-id in template.

	* semantics.c (finish_qualified_id_expr): build_qualified_name
	for unbound names in the current class.

From-SVN: r261196

gcc/cp/ChangeLog

+2018-06-05  Jason Merrill  <jason@redhat.com>
+
+	PR c++/85731 - wrong error with qualified-id in template.
+	* semantics.c (finish_qualified_id_expr): build_qualified_name
+	for unbound names in the current class.
+
 2018-06-04  Jason Merrill  <jason@redhat.com>
 
 	PR c++/61806 - missed SFINAE with partial specialization.

gcc/cp/semantics.c

@@ -2098,6 +2098,8 @@ finish_qualified_id_expr (tree qualifying_class,
 	 non-type template argument handling.  */
       if (processing_template_decl
 	  && (!currently_open_class (qualifying_class)
+	      || TREE_CODE (expr) == IDENTIFIER_NODE
+	      || TREE_CODE (expr) == TEMPLATE_ID_EXPR
 	      || TREE_CODE (expr) == BIT_NOT_EXPR))
 	expr = build_qualified_name (TREE_TYPE (expr),
 				     qualifying_class, expr,

gcc/testsuite/g++.dg/template/qualified-id7.C

+// PR c++/85731
+// { dg-do compile { target c++11 } }
+
+    template <typename T>
+    struct Outer {
+        struct Inner;
+        template <int I> static void f();
+    };
+
+    template <typename T>
+    struct Outer<T>::Inner {
+        decltype(Outer<T>::f<42>()) f();
+    };
+
+    int main() { Outer<int>::Inner().f(); }