Compiler projects using llvm
/*===---- stddef.h - Basic type definitions --------------------------------===
 *
 * 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
 *
 *===-----------------------------------------------------------------------===
 */

#if !defined(__STDDEF_H) || defined(__need_ptrdiff_t) ||                       \
    defined(__need_size_t) || defined(__need_wchar_t) ||                       \
    defined(__need_NULL) || defined(__need_wint_t)

#if !defined(__need_ptrdiff_t) && !defined(__need_size_t) &&                   \
    !defined(__need_wchar_t) && !defined(__need_NULL) &&                       \
    !defined(__need_wint_t)
/* Always define miscellaneous pieces when modules are available. */
#if !__has_feature(modules)
#define __STDDEF_H
#endif
#define __need_ptrdiff_t
#define __need_size_t
#define __need_wchar_t
#define __need_NULL
#define __need_STDDEF_H_misc
/* __need_wint_t is intentionally not defined here. */
#endif

#if defined(__need_ptrdiff_t)
#if !defined(_PTRDIFF_T) || __has_feature(modules)
/* Always define ptrdiff_t when modules are available. */
#if !__has_feature(modules)
#define _PTRDIFF_T
#endif
typedef __PTRDIFF_TYPE__ ptrdiff_t;
#endif
#undef __need_ptrdiff_t
#endif /* defined(__need_ptrdiff_t) */

#if defined(__need_size_t)
#if !defined(_SIZE_T) || __has_feature(modules)
/* Always define size_t when modules are available. */
#if !__has_feature(modules)
#define _SIZE_T
#endif
typedef __SIZE_TYPE__ size_t;
#endif
#undef __need_size_t
#endif /*defined(__need_size_t) */

#if defined(__need_STDDEF_H_misc)
/* ISO9899:2011 7.20 (C11 Annex K): Define rsize_t if __STDC_WANT_LIB_EXT1__ is
 * enabled. */
#if (defined(__STDC_WANT_LIB_EXT1__) && __STDC_WANT_LIB_EXT1__ >= 1 && \
     !defined(_RSIZE_T)) || __has_feature(modules)
/* Always define rsize_t when modules are available. */
#if !__has_feature(modules)
#define _RSIZE_T
#endif
typedef __SIZE_TYPE__ rsize_t;
#endif
#endif /* defined(__need_STDDEF_H_misc) */

#if defined(__need_wchar_t)
#if !defined(__cplusplus) || (defined(_MSC_VER) && !_NATIVE_WCHAR_T_DEFINED)
/* Always define wchar_t when modules are available. */
#if !defined(_WCHAR_T) || __has_feature(modules)
#if !__has_feature(modules)
#define _WCHAR_T
#if defined(_MSC_EXTENSIONS)
#define _WCHAR_T_DEFINED
#endif
#endif
typedef __WCHAR_TYPE__ wchar_t;
#endif
#endif
#undef __need_wchar_t
#endif /* defined(__need_wchar_t) */

#if defined(__need_NULL)
#undef NULL
#ifdef __cplusplus
#  if !defined(__MINGW32__) && !defined(_MSC_VER)
#    define NULL __null
#  else
#    define NULL 0
#  endif
#else
#  define NULL ((void*)0)
#endif
#ifdef __cplusplus
#if defined(_MSC_EXTENSIONS) && defined(_NATIVE_NULLPTR_SUPPORTED)
namespace std { typedef decltype(nullptr) nullptr_t; }
using ::std::nullptr_t;
#endif
#endif
#undef __need_NULL
#endif /* defined(__need_NULL) */

#if defined(__need_STDDEF_H_misc)
#if __STDC_VERSION__ >= 201112L || __cplusplus >= 201103L
#include "__stddef_max_align_t.h"
#endif
#define offsetof(t, d) __builtin_offsetof(t, d)
#undef __need_STDDEF_H_misc
#endif  /* defined(__need_STDDEF_H_misc) */

/* Some C libraries expect to see a wint_t here. Others (notably MinGW) will use
__WINT_TYPE__ directly; accommodate both by requiring __need_wint_t */
#if defined(__need_wint_t)
/* Always define wint_t when modules are available. */
#if !defined(_WINT_T) || __has_feature(modules)
#if !__has_feature(modules)
#define _WINT_T
#endif
typedef __WINT_TYPE__ wint_t;
#endif
#undef __need_wint_t
#endif /* __need_wint_t */

#endif