148 lines
5 KiB
C
148 lines
5 KiB
C
|
/* A substitute for POSIX 2008 <stddef.h>, for platforms that have issues.
|
||
|
|
||
|
Copyright (C) 2009-2023 Free Software Foundation, Inc.
|
||
|
|
||
|
This file is free software: you can redistribute it and/or modify
|
||
|
it under the terms of the GNU Lesser General Public License as
|
||
|
published by the Free Software Foundation; either version 2.1 of the
|
||
|
License, or (at your option) any later version.
|
||
|
|
||
|
This file is distributed in the hope that it will be useful,
|
||
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
|
GNU Lesser General Public License for more details.
|
||
|
|
||
|
You should have received a copy of the GNU Lesser General Public License
|
||
|
along with this program. If not, see <https://www.gnu.org/licenses/>. */
|
||
|
|
||
|
/* Written by Eric Blake. */
|
||
|
|
||
|
/*
|
||
|
* POSIX 2008 <stddef.h> for platforms that have issues.
|
||
|
* <https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/stddef.h.html>
|
||
|
*/
|
||
|
|
||
|
#if __GNUC__ >= 3
|
||
|
@PRAGMA_SYSTEM_HEADER@
|
||
|
#endif
|
||
|
@PRAGMA_COLUMNS@
|
||
|
|
||
|
#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
|
||
|
# @INCLUDE_NEXT@ @NEXT_STDDEF_H@
|
||
|
/* On TinyCC, make sure that the macros that indicate the special invocation
|
||
|
convention get undefined. */
|
||
|
# undef __need_wchar_t
|
||
|
# undef __need_size_t
|
||
|
# undef __need_ptrdiff_t
|
||
|
# undef __need_NULL
|
||
|
# undef __need_wint_t
|
||
|
# endif
|
||
|
|
||
|
#else
|
||
|
/* Normal invocation convention. */
|
||
|
|
||
|
# ifndef _@GUARD_PREFIX@_STDDEF_H
|
||
|
|
||
|
/* 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 __LP64__
|
||
|
# 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. */
|
||
|
|
||
|
# @INCLUDE_NEXT@ @NEXT_STDDEF_H@
|
||
|
|
||
|
/* 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
|
||
|
|
||
|
# ifndef _@GUARD_PREFIX@_STDDEF_H
|
||
|
# define _@GUARD_PREFIX@_STDDEF_H
|
||
|
|
||
|
/* Some platforms lack wchar_t. */
|
||
|
#if !@HAVE_WCHAR_T@
|
||
|
# define wchar_t int
|
||
|
#endif
|
||
|
|
||
|
/* 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).
|
||
|
Similarly on OS/2 kLIBC. */
|
||
|
#if (defined _MSC_VER || (defined __KLIBC__ && !defined __LIBCN__)) \
|
||
|
&& defined __cplusplus
|
||
|
# include <cstddef>
|
||
|
#else
|
||
|
# if ! (@HAVE_MAX_ALIGN_T@ || (defined _GCC_MAX_ALIGN_T && !defined __clang__))
|
||
|
# 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
|
||
|
|
||
|
# endif /* _@GUARD_PREFIX@_STDDEF_H */
|
||
|
# endif /* _@GUARD_PREFIX@_STDDEF_H */
|
||
|
#endif /* __need_XXX */
|