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// <optional> 11 12// constexpr optional() noexcept; 13 14#include <experimental/optional> 15#include <type_traits> 16#include <cassert> 17 18#if _LIBCPP_STD_VER > 11 19 20using std::experimental::optional; 21 22template <class Opt> 23void 24test_constexpr() 25{ 26 static_assert(std::is_nothrow_default_constructible<Opt>::value, ""); 27 constexpr Opt opt; 28 static_assert(static_cast<bool>(opt) == false, ""); 29 30 struct test_constexpr_ctor 31 : public Opt 32 { 33 constexpr test_constexpr_ctor() {} 34 }; 35 36} 37 38template <class Opt> 39void 40test() 41{ 42 static_assert(std::is_nothrow_default_constructible<Opt>::value, ""); 43 Opt opt; 44 assert(static_cast<bool>(opt) == false); 45 46 struct test_constexpr_ctor 47 : public Opt 48 { 49 constexpr test_constexpr_ctor() {} 50 }; 51} 52 53struct X 54{ 55 X(); 56}; 57 58#endif // _LIBCPP_STD_VER > 11 59 60int main() 61{ 62#if _LIBCPP_STD_VER > 11 63 test_constexpr<optional<int>>(); 64 test_constexpr<optional<int*>>(); 65 test<optional<X>>(); 66#endif // _LIBCPP_STD_VER > 11 67} 68