diff --git a/gcc/cp/constexpr.cc b/gcc/cp/constexpr.cc
index abf6ee560c5..3de60cfd0f8 100644
--- a/gcc/cp/constexpr.cc
+++ b/gcc/cp/constexpr.cc
@@ -8796,6 +8796,10 @@ maybe_constant_init_1 (tree t, tree decl, bool allow_non_constant,
 			&& (TREE_STATIC (decl) || DECL_EXTERNAL (decl)));
       if (is_static)
 	manifestly_const_eval = true;
+
+      if (cp_unevaluated_operand && !manifestly_const_eval)
+	return fold_to_constant (t);
+
       t = cxx_eval_outermost_constant_expr (t, allow_non_constant, !is_static,
 					    mce_value (manifestly_const_eval),
 					    false, decl);
diff --git a/gcc/testsuite/g++.dg/cpp2a/constexpr-inst2.C b/gcc/testsuite/g++.dg/cpp2a/constexpr-inst2.C
new file mode 100644
index 00000000000..7676b625321
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/constexpr-inst2.C
@@ -0,0 +1,12 @@
+// { dg-do compile { target c++11 } }
+
+struct __as_receiver {
+  int empty_env;
+};
+
+template<class T>
+constexpr int f(T t) {
+  return t.fail;
+};
+
+using type = decltype(__as_receiver{f(0)}); // OK, f<int> not instantiated