xref: /freebsd-10-stable/contrib/libc++/include/cstddef

// -*- C++ -*-
//===--------------------------- cstddef ----------------------------------===//
//
//                     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.
//
//===----------------------------------------------------------------------===//

#ifndef _LIBCPP_CSTDDEF
#define _LIBCPP_CSTDDEF

/*
    cstddef synopsis

Macros:

    offsetof(type,member-designator)
    NULL

namespace std
{

Types:

    ptrdiff_t
    size_t
    max_align_t
    nullptr_t

}  // std

*/

#include <__config>

#include <stddef.h>

#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif

_LIBCPP_BEGIN_NAMESPACE_STD

using ::ptrdiff_t;
using ::size_t;

#if defined(__CLANG_MAX_ALIGN_T_DEFINED) || defined(_GCC_MAX_ALIGN_T)
// Re-use the compiler's <stddef.h> max_align_t where possible.
using ::max_align_t;
#else
typedef long double max_align_t;
#endif

#ifdef _LIBCPP_HAS_NO_NULLPTR

struct _LIBCPP_TYPE_VIS_ONLY nullptr_t
{
    void* __lx;

    struct __nat {int __for_bool_;};

    _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR nullptr_t() : __lx(0) {}
    _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR nullptr_t(int __nat::*) : __lx(0) {}

    _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR operator int __nat::*() const {return 0;}

    template <class _Tp>
        _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR
        operator _Tp* () const {return 0;}

    template <class _Tp, class _Up>
        _LIBCPP_ALWAYS_INLINE
        operator _Tp _Up::* () const {return 0;}

    friend _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR bool operator==(nullptr_t, nullptr_t) {return true;}
    friend _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR bool operator!=(nullptr_t, nullptr_t) {return false;}
    friend _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR bool operator<(nullptr_t, nullptr_t) {return false;}
    friend _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR bool operator<=(nullptr_t, nullptr_t) {return true;}
    friend _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR bool operator>(nullptr_t, nullptr_t) {return false;}
    friend _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR bool operator>=(nullptr_t, nullptr_t) {return true;}
};

inline _LIBCPP_ALWAYS_INLINE _LIBCPP_CONSTEXPR nullptr_t __get_nullptr_t() {return nullptr_t(0);}

#define nullptr _VSTD::__get_nullptr_t()

#endif  // _LIBCPP_HAS_NO_NULLPTR

_LIBCPP_END_NAMESPACE_STD

#ifndef _LIBCPP_HAS_NO_NULLPTR

namespace std
{
    typedef decltype(nullptr) nullptr_t;
}

#endif  // _LIBCPP_HAS_NO_NULLPTR

#endif  // _LIBCPP_CSTDDEF