diff --git a/gcc/testsuite/g++.dg/cpp1z/class-deduction77.C b/gcc/testsuite/g++.dg/cpp1z/class-deduction77.C
new file mode 100644
index 00000000000..c5462fb4f32
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp1z/class-deduction77.C
@@ -0,0 +1,6 @@
+// { dg-do compile { target c++17 } }
+
+template <class...> struct A {};
+
+template <template <class> class... Ts>
+using B = A<decltype(Ts{0})...>;