xref: /llvm-project/libcxx/test/std/utilities/optional/optional.syn/optional_nullopt_t.verify.cpp (revision dc71a77d33620830020c939bba25ebdfdd1b6194)
1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // UNSUPPORTED: c++03, c++11, c++14
10 
11 // <optional>
12 
13 // A program that necessitates the instantiation of template optional for
14 // (possibly cv-qualified) nullopt_t is ill-formed.
15 
16 #include <optional>
17 
f()18 void f() {
19     std::optional<std::nullopt_t> opt; // expected-note 1 {{requested here}}
20     std::optional<const std::nullopt_t> opt1; // expected-note 1 {{requested here}}
21     std::optional<std::nullopt_t &> opt2; // expected-note 1 {{requested here}}
22     std::optional<std::nullopt_t &&> opt3; // expected-note 1 {{requested here}}
23     // expected-error@optional:* 4 {{instantiation of optional with nullopt_t is ill-formed}}
24 }
25