--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/cpp1z/constexpr-lambda22.C	Thu Feb 13 11:34:05 2020 +0900
@@ -0,0 +1,20 @@
+// { dg-do compile }
+// { dg-options -std=c++17 }
+
+#define SA(X) static_assert((X),#X)
+
+template<typename>
+constexpr int
+foo ()
+{
+  constexpr int a[] = { 1, 2, 3, 4, 5 };
+  int i = 0;
+  auto j = [&] {
+    for (auto x : a)
+      i++;
+    return i;
+  }();
+  return j;
+}
+
+SA (foo<int>() == 5);