Richard Smith d6cffc4fe0 Split <stddef.h> out of <cstddef>.
There are a bunch of macros (__need_size_t etc) that request just one piece of
<stddef.h>; if any one of these is defined, we just directly include the
underlying header.

Note that <stddef.h> provides a ::nullptr_t. We don't want that available to
includers of <cstddef>, so instead of following the usual pattern where <cfoo>
includes <foo.h> then pulls things from :: into std:: with using-declarations,
we implement <stddef.h> and <cstddef> separately; both include <__nullptr> for
the definition of std::nullptr_t.

llvm-svn: 249761
2015-10-08 22:25:27 +00:00

57 lines
1.1 KiB
C++

// -*- C++ -*-
//===--------------------------- stddef.h ---------------------------------===//
//
// 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.
//
//===----------------------------------------------------------------------===//
#if defined(__need_ptrdiff_t) || defined(__need_size_t) || \
defined(__need_wchar_t) || defined(__need_NULL) || defined(__need_wint_t)
#include_next <stddef.h>
#elif !defined(_LIBCPP_STDDEF_H)
#define _LIBCPP_STDDEF_H
/*
stddef.h synopsis
Macros:
offsetof(type,member-designator)
NULL
Types:
ptrdiff_t
size_t
max_align_t
nullptr_t
*/
#include <__config>
#include_next <stddef.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif
#ifdef __cplusplus
extern "C++" {
#include <__nullptr>
using std::nullptr_t;
}
// Re-use the compiler's <stddef.h> max_align_t where possible.
#if !defined(__CLANG_MAX_ALIGN_T_DEFINED) && !defined(_GCC_MAX_ALIGN_T)
typedef long double max_align_t;
#endif
#endif
#endif // _LIBCPP_STDDEF_H