Nikolas Klauser 17e0686ab1
[libc++][NFC] Use [[__nodiscard__]] unconditionally (#80454)
`__has_cpp_attribute(__nodiscard__)` is always true now, so we might as
well replace `_LIBCPP_NODISCARD`. It's one less macro that can result in
bad diagnostics.
2024-09-12 21:18:43 +02:00

45 lines
1.3 KiB
C++

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
// 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___BIT_BIT_CAST_H
#define _LIBCPP___BIT_BIT_CAST_H
#include <__config>
#include <__type_traits/is_trivially_copyable.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
_LIBCPP_BEGIN_NAMESPACE_STD
#ifndef _LIBCPP_CXX03_LANG
template <class _ToType, class _FromType>
[[__nodiscard__]] _LIBCPP_HIDE_FROM_ABI constexpr _ToType __bit_cast(const _FromType& __from) noexcept {
return __builtin_bit_cast(_ToType, __from);
}
#endif // _LIBCPP_CXX03_LANG
#if _LIBCPP_STD_VER >= 20
template <class _ToType, class _FromType>
requires(sizeof(_ToType) == sizeof(_FromType) && is_trivially_copyable_v<_ToType> &&
is_trivially_copyable_v<_FromType>)
[[nodiscard]] _LIBCPP_HIDE_FROM_ABI constexpr _ToType bit_cast(const _FromType& __from) noexcept {
return __builtin_bit_cast(_ToType, __from);
}
#endif // _LIBCPP_STD_VER >= 20
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP___BIT_BIT_CAST_H