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 // <memory>
10 
11 // template <class Alloc>
12 // struct allocator_traits
13 // {
14 //     static constexpr pointer allocate(allocator_type& a, size_type n);
15 //     ...
16 // };
17 
18 // UNSUPPORTED: c++03, c++11, c++14, c++17
19 
20 #include <cstddef>
21 #include <memory>
22 
23 template <class T>
24 struct A {
25     typedef T value_type;
26     value_type* allocate(std::size_t n);
27     value_type* allocate(std::size_t n, const void* p);
28 };
29 
f()30 void f() {
31     A<int> a;
32     std::allocator_traits<A<int> >::allocate(a, 10);          // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
33     std::allocator_traits<A<int> >::allocate(a, 10, nullptr); // expected-warning {{ignoring return value of function declared with 'nodiscard' attribute}}
34 }
35