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
10
11 // <tuple>
12
13 // See https://llvm.org/PR20855
14
15 #include <tuple>
16 #include <string>
17
18 #include "test_macros.h"
19
20 template <class Tp>
21 struct ConvertsTo {
22 using RawTp = typename std::remove_cv< typename std::remove_reference<Tp>::type>::type;
23
operator TpConvertsTo24 operator Tp() const {
25 return static_cast<Tp>(value);
26 }
27
28 mutable RawTp value;
29 };
30
31 struct Base {};
32 struct Derived : Base {};
33
34 template <class T> struct CannotDeduce {
35 using type = T;
36 };
37
38 template <class ...Args>
F(typename CannotDeduce<std::tuple<Args...>>::type const &)39 void F(typename CannotDeduce<std::tuple<Args...>>::type const&) {}
40
41
f()42 void f() {
43 #if TEST_HAS_BUILTIN_IDENTIFIER(__reference_binds_to_temporary)
44 // Test that we emit our diagnostic from the library.
45 // expected-error@tuple:* 8 {{Attempted construction of reference element binds to a temporary whose lifetime has ended}}
46
47 // Good news everybody! Clang now diagnoses this for us!
48 // expected-error@tuple:* 0+ {{reference member '__value_' binds to a temporary object whose lifetime would be shorter than the lifetime of the constructed object}}
49
50 {
51 F<int, const std::string&>(std::make_tuple(1, "abc")); // expected-note 1 {{requested here}}
52 }
53 {
54 std::tuple<int, const std::string&> t(1, "a"); // expected-note 1 {{requested here}}
55 }
56 {
57 F<int, const std::string&>(std::tuple<int, const std::string&>(1, "abc")); // expected-note 1 {{requested here}}
58 }
59 {
60 ConvertsTo<int&> ct;
61 std::tuple<const long&, int> t(ct, 42); // expected-note {{requested here}}
62 }
63 {
64 ConvertsTo<int> ct;
65 std::tuple<int const&, void*> t(ct, nullptr); // expected-note {{requested here}}
66 }
67 {
68 ConvertsTo<Derived> ct;
69 std::tuple<Base const&, int> t(ct, 42); // expected-note {{requested here}}
70 }
71 {
72 std::allocator<int> alloc;
73 std::tuple<std::string &&> t2("hello"); // expected-note {{requested here}}
74 std::tuple<std::string &&> t3(std::allocator_arg, alloc, "hello"); // expected-note {{requested here}}
75 }
76 #else
77 #error force failure
78 // expected-error@-1 {{force failure}}
79 #endif
80 }
81