1//===----------------------------------------------------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is dual licensed under the MIT and the University of Illinois Open
6// Source Licenses. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10// <string>
11
12// basic_string()
13//        noexcept(is_nothrow_default_constructible<allocator_type>::value);
14
15// This tests a conforming extension
16
17#include <string>
18#include <cassert>
19
20#include "test_allocator.h"
21
22template <class T>
23struct some_alloc
24{
25    typedef T value_type;
26    some_alloc(const some_alloc&);
27};
28
29int main()
30{
31#if __has_feature(cxx_noexcept)
32    {
33        typedef std::string C;
34        static_assert(std::is_nothrow_default_constructible<C>::value, "");
35    }
36    {
37        typedef std::basic_string<char, std::char_traits<char>, test_allocator<char>> C;
38        static_assert(std::is_nothrow_default_constructible<C>::value, "");
39    }
40    {
41        typedef std::basic_string<char, std::char_traits<char>, some_alloc<char>> C;
42        static_assert(!std::is_nothrow_default_constructible<C>::value, "");
43    }
44#endif
45}
46