--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gcc/testsuite/g++.dg/ext/temp-extend1.C	Thu Feb 13 11:34:05 2020 +0900
@@ -0,0 +1,43 @@
+// PR c++/92831
+// { dg-do run { target c++11 } }
+// { dg-options "" }
+
+template<typename T> using id = T;
+struct S { S () : s (false) { ++c; } S (bool x) : s (x) { ++c; } ~S () { --c; }; bool s; static int c; };
+int S::c = 0;
+
+void
+foo (int i)
+{
+  const bool&& a
+    = id<S[3]>{false, true, false}[i].s
+      ? id<S[2]>{true, false}[i].s : id<S[4]>{true, false, true, false}[i].s;
+  if (S::c != (i ? 2 : 4))
+    __builtin_abort ();
+}
+
+void
+baz (int i)
+{
+  const bool&& a = id<S[3]>{false, true, false}[i].s
+		   ? : id<S[4]>{true, false, true, false}[i].s;
+  if (S::c != (i ? 0 : 4))
+    __builtin_abort ();
+}
+
+int
+main ()
+{
+  foo (0);
+  if (S::c != 0)
+    __builtin_abort ();
+  foo (1);
+  if (S::c != 0)
+    __builtin_abort ();
+  baz (0);
+  if (S::c != 0)
+    __builtin_abort ();
+  baz (1);
+  if (S::c != 0)
+    __builtin_abort ();
+}