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/* A substitute for POSIX 2008 <stddef.h>, for platforms that have issues.
Copyright (C) 2009-2021 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, or (at your option)
any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, see <>. */
/* Written by Eric Blake. */
* POSIX 2008 <stddef.h> for platforms that have issues.
* <>
#if __GNUC__ >= 3
#if defined __need_wchar_t || defined __need_size_t \
|| defined __need_ptrdiff_t || defined __need_NULL \
|| defined __need_wint_t
/* Special invocation convention inside gcc header files. In
particular, gcc provides a version of <stddef.h> that blindly
redefines NULL even when __need_wint_t was defined, even though
wint_t is not normally provided by <stddef.h>. Hence, we must
remember if special invocation has ever been used to obtain wint_t,
in which case we need to clean up NULL yet again. */
# if !(defined _@GUARD_PREFIX@_STDDEF_H && defined _GL_STDDEF_WINT_T)
# ifdef __need_wint_t
# define _GL_STDDEF_WINT_T
# endif
# endif
/* Normal invocation convention. */
/* On AIX 7.2, with xlc in 64-bit mode, <stddef.h> defines max_align_t to a
type with alignment 4, but 'long' has alignment 8. */
# if defined _AIX && defined _ARCH_PPC64
# if !GNULIB_defined_max_align_t
# ifdef _MAX_ALIGN_T
/* /usr/include/stddef.h has already defined max_align_t. Override it. */
typedef long rpl_max_align_t;
# define max_align_t rpl_max_align_t
# else
/* Prevent /usr/include/stddef.h from defining max_align_t. */
typedef long max_align_t;
# define _MAX_ALIGN_T
# endif
# define GNULIB_defined_max_align_t 1
# endif
# endif
/* The include_next requires a split double-inclusion guard. */
/* On NetBSD 5.0, the definition of NULL lacks proper parentheses. */
# if (@REPLACE_NULL@ \
&& (!defined _@GUARD_PREFIX@_STDDEF_H || defined _GL_STDDEF_WINT_T))
# undef NULL
# ifdef __cplusplus
/* ISO C++ says that the macro NULL must expand to an integer constant
expression, hence '((void *) 0)' is not allowed in C++. */
# if __GNUG__ >= 3
/* GNU C++ has a __null macro that behaves like an integer ('int' or
'long') but has the same size as a pointer. Use that, to avoid
warnings. */
# define NULL __null
# else
# define NULL 0L
# endif
# else
# define NULL ((void *) 0)
# endif
# endif
/* Some platforms lack wchar_t. */
# define wchar_t int
/* Some platforms lack max_align_t. The check for _GCC_MAX_ALIGN_T is
a hack in case the configure-time test was done with g++ even though
we are currently compiling with gcc.
On MSVC, max_align_t is defined only in C++ mode, after <cstddef> was
included. Its definition is good since it has an alignment of 8 (on x86
and x86_64). */
#if defined _MSC_VER && defined __cplusplus
# include <cstddef>
# if ! (@HAVE_MAX_ALIGN_T@ || defined _GCC_MAX_ALIGN_T)
# if !GNULIB_defined_max_align_t
/* On the x86, the maximum storage alignment of double, long, etc. is 4,
but GCC's C11 ABI for x86 says that max_align_t has an alignment of 8,
and the C11 standard allows this. Work around this problem by
using __alignof__ (which returns 8 for double) rather than _Alignof
(which returns 4), and align each union member accordingly. */
# if defined __GNUC__ || (__clang_major__ >= 4)
# define _GL_STDDEF_ALIGNAS(type) \
__attribute__ ((__aligned__ (__alignof__ (type))))
# else
# define _GL_STDDEF_ALIGNAS(type) /* */
# endif
typedef union
char *__p _GL_STDDEF_ALIGNAS (char *);
double __d _GL_STDDEF_ALIGNAS (double);
long double __ld _GL_STDDEF_ALIGNAS (long double);
long int __i _GL_STDDEF_ALIGNAS (long int);
} rpl_max_align_t;
# define max_align_t rpl_max_align_t
# define GNULIB_defined_max_align_t 1
# endif
# endif
# endif /* _@GUARD_PREFIX@_STDDEF_H */
# endif /* _@GUARD_PREFIX@_STDDEF_H */
#endif /* __need_XXX */