--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/cpp1y/constexpr-array6.C	Thu Oct 25 07:37:49 2018 +0900
@@ -0,0 +1,26 @@
+// PR c++/87075
+// { dg-do compile { target c++14 } }
+
+template <typename T>
+struct vec
+{
+  struct { T y; } n;
+  vec() = default;
+};
+
+template <typename T>
+struct S
+{
+  vec<T> value[2];
+  template<typename U>
+  constexpr S(const U&);
+};
+
+template<typename T>
+template<typename X>
+constexpr S<T>::S(const X&)
+{
+  value[0] = vec<T>();
+}
+
+S<float>m(0);