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/* A substitute for POSIX 2008 <stddef.h>, for platforms that have issues.

   Copyright (C) 2009-2016 Free Software Foundation, Inc.

   This program is free software: you can redistribute it and/or
   modify it under the terms of either:

     * the GNU Lesser General Public License as published by the Free
       Software Foundation; either version 3 of the License, or (at your
       option) any later version.

   or

     * the GNU General Public License as published by the Free
       Software Foundation; either version 2 of the License, or (at your
       option) any later version.

   or both in parallel, as here.
   This program 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 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 <http://www.gnu.org/licenses/>.  */

/* Written by Eric Blake.  */

/*
 * POSIX 2008 <stddef.h> for platforms that have issues.
 * <http://www.opengroup.org/susv3xbd/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@
# endif

#else
/* Normal invocation convention.  */

# ifndef _@GUARD_PREFIX@_STDDEF_H

/* 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.  */
#if ! (@HAVE_MAX_ALIGN_T@ || defined _GCC_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.  */
# ifdef __GNUC__
#  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);
} max_align_t;
#endif

#  endif /* _@GUARD_PREFIX@_STDDEF_H */
# endif /* _@GUARD_PREFIX@_STDDEF_H */
#endif /* __need_XXX */