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//===----------------------------------------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
// <optional>
// constexpr optional() noexcept;
#include <experimental/optional>
#include <type_traits>
#include <cassert>
#if _LIBCPP_STD_VER > 11
using std::experimental::optional;
template <class Opt>
void
test_constexpr()
{
static_assert(std::is_nothrow_default_constructible<Opt>::value, "");
constexpr Opt opt;
static_assert(static_cast<bool>(opt) == false, "");
struct test_constexpr_ctor
: public Opt
{
constexpr test_constexpr_ctor() {}
};
}
template <class Opt>
void
test()
{
static_assert(std::is_nothrow_default_constructible<Opt>::value, "");
Opt opt;
assert(static_cast<bool>(opt) == false);
struct test_constexpr_ctor
: public Opt
{
constexpr test_constexpr_ctor() {}
};
}
struct X
{
X();
};
#endif // _LIBCPP_STD_VER > 11
int main()
{
#if _LIBCPP_STD_VER > 11
test_constexpr<optional<int>>();
test_constexpr<optional<int*>>();
test<optional<X>>();
#endif // _LIBCPP_STD_VER > 11
}
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