--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/cpp0x/alias-decl-66.C	Thu Feb 13 11:34:05 2020 +0900
@@ -0,0 +1,21 @@
+// PR c++/87366
+// { dg-do compile { target c++11 } }
+
+struct A {};
+struct B {};
+
+template <typename T> struct wrapper {};
+
+template <typename> struct enable_if_A { };
+template<> struct enable_if_A<A> { using type = void; };
+
+template <typename T, typename = typename enable_if_A<T>::type> using ok_t = T;
+
+template <typename T> void not_even_called(wrapper<const ok_t<T>&> a);
+
+template <typename T> int called(wrapper<const T&> a);
+
+void test(wrapper<const B&>& val)
+{
+    called(val);
+}