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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP___TYPE_TRAITS_IS_IMPLICITLY_DEFAULT_CONSTRUCTIBLE_H
#define _LIBCPP___TYPE_TRAITS_IS_IMPLICITLY_DEFAULT_CONSTRUCTIBLE_H
#include <__config>
#include <__type_traits/integral_constant.h>
#include <__type_traits/is_default_constructible.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
#ifndef _LIBCPP_CXX03_LANG
// First of all, we can't implement this check in C++03 mode because the {}
// default initialization syntax isn't valid.
// Second, we implement the trait in a funny manner with two defaulted template
// arguments to workaround Clang's PR43454.
template <class _Tp>
void __test_implicit_default_constructible(_Tp);
template <class _Tp, class = void, class = typename is_default_constructible<_Tp>::type>
struct __is_implicitly_default_constructible
: false_type
{ };
template <class _Tp>
struct __is_implicitly_default_constructible<_Tp, decltype(__test_implicit_default_constructible<_Tp const&>({})), true_type>
: true_type
{ };
template <class _Tp>
struct __is_implicitly_default_constructible<_Tp, decltype(__test_implicit_default_constructible<_Tp const&>({})), false_type>
: false_type
{ };
#endif // !C++03
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___TYPE_TRAITS_IS_IMPLICITLY_DEFAULT_CONSTRUCTIBLE_H