projects / ceph.git / blame
| Commit | Line | Data |
|---|---|---|
| 11fdf7f2 TL |
1 | /* |
| 2 | * Distributed under the Boost Software License, Version 1.0. | |
| 3 | * (See accompanying file LICENSE_1_0.txt or copy at | |
| 4 | * http://www.boost.org/LICENSE_1_0.txt) | |
| 5 | * | |
| 6 | * Copyright (c) 2018 Andrey Semashev | |
| 7 | */ | |
| 8 | /*! | |
| 9 | * \file atomic/detail/addressof.hpp | |
| 10 | * | |
| 11 | * This header defines \c addressof helper function. It is similar to \c boost::addressof but it is more | |
| 12 | * lightweight and also contains a workaround for some compiler warnings. | |
| 13 | */ | |
| 14 | ||
| 15 | #ifndef BOOST_ATOMIC_DETAIL_ADDRESSOF_HPP_INCLUDED_ | |
| 16 | #define BOOST_ATOMIC_DETAIL_ADDRESSOF_HPP_INCLUDED_ | |
| 17 | ||
| 18 | #include <boost/atomic/detail/config.hpp> | |
| 20effc67 | 19 | #include <boost/atomic/detail/header.hpp> |
| 11fdf7f2 TL |
20 | |
| 21 | #ifdef BOOST_HAS_PRAGMA_ONCE | |
| 22 | #pragma once | |
| 23 | #endif | |
| 24 | ||
| 25 | // Detection logic is based on boost/core/addressof.hpp | |
| 26 | #if defined(BOOST_MSVC_FULL_VER) && BOOST_MSVC_FULL_VER >= 190024215 | |
| 27 | #define BOOST_ATOMIC_DETAIL_HAS_BUILTIN_ADDRESSOF | |
| 28 | #elif defined(BOOST_GCC) && BOOST_GCC >= 70000 | |
| 29 | #define BOOST_ATOMIC_DETAIL_HAS_BUILTIN_ADDRESSOF | |
| 30 | #elif defined(__has_builtin) | |
| 31 | #if __has_builtin(__builtin_addressof) | |
| 32 | #define BOOST_ATOMIC_DETAIL_HAS_BUILTIN_ADDRESSOF | |
| 33 | #endif | |
| 34 | #endif | |
| 35 | ||
| 36 | namespace boost { | |
| 37 | namespace atomics { | |
| 38 | namespace detail { | |
| 39 | ||
| 40 | template< typename T > | |
| 1e59de90 TL |
41 | BOOST_FORCEINLINE |
| 42 | #if defined(BOOST_ATOMIC_DETAIL_HAS_BUILTIN_ADDRESSOF) | |
| 43 | BOOST_CONSTEXPR | |
| 44 | #endif | |
| 45 | T* addressof(T& value) BOOST_NOEXCEPT | |
| 11fdf7f2 TL |
46 | { |
| 47 | #if defined(BOOST_ATOMIC_DETAIL_HAS_BUILTIN_ADDRESSOF) | |
| 48 | return __builtin_addressof(value); | |
| 49 | #else | |
| 50 | // Note: The point of using a local struct as the intermediate type instead of char is to avoid gcc warnings | |
| 51 | // if T is a const volatile char*: | |
| 52 | // warning: casting 'const volatile char* const' to 'const volatile char&' does not dereference pointer | |
| 53 | // The local struct makes sure T is not related to the cast target type. | |
| 54 | struct opaque_type; | |
| 55 | return reinterpret_cast< T* >(&const_cast< opaque_type& >(reinterpret_cast< const volatile opaque_type& >(value))); | |
| 56 | #endif | |
| 57 | } | |
| 58 | ||
| 59 | } // namespace detail | |
| 60 | } // namespace atomics | |
| 61 | } // namespace boost | |
| 62 | ||
| 20effc67 TL |
63 | #include <boost/atomic/detail/footer.hpp> |
| 64 | ||
| 11fdf7f2 | 65 | #endif // BOOST_ATOMIC_DETAIL_ADDRESSOF_HPP_INCLUDED_ |