default.pass.cpp revision c10e963f3d17c11a34ff4da9810940e63b130a7d 
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// Usage of is_trivially_constructible is broken with these compilers.
11// See https://bugs.llvm.org/show_bug.cgi?id=31016
12// XFAIL: clang-3.7, apple-clang-7, apple-clang-7.0
13
14// <iterator>
15
16// class istream_iterator
17
18// constexpr istream_iterator();
19// C++17 says: If is_trivially_default_constructible_v<T> is true, then this
20//    constructor is a constexpr constructor.
21
22#include <iterator>
23#include <cassert>
24#include <string>
25
26#include "test_macros.h"
27
28struct S { S(); }; // not constexpr
29
30#if TEST_STD_VER > 14
31template <typename T, bool isTrivial = std::is_trivially_default_constructible_v<T>>
32struct test_trivial {
33void operator ()() const {
34    constexpr std::istream_iterator<T> it;
35    }
36};
37
38template <typename T>
39struct test_trivial<T, false> {
40void operator ()() const {}
41};
42#endif
43
44
45int main()
46{
47    {
48    typedef std::istream_iterator<int> T;
49    T it;
50    assert(it == T());
51#if TEST_STD_VER >= 11
52    constexpr T it2;
53#endif
54    }
55
56#if TEST_STD_VER > 14
57    test_trivial<int>()();
58    test_trivial<char>()();
59    test_trivial<double>()();
60    test_trivial<S>()();
61    test_trivial<std::string>()();
62#endif
63}
64