Sync with the latest Gnulib code (1a268176f)

1 files changed, 86 insertions, 25 deletions

diff --git a/gl/stddef.in.h b/gl/stddef.in.h
index 40f0536a..42290d44 100644
--- a/gl/stddef.in.h
+++ b/gl/stddef.in.h
@@ -1,25 +1,25 @@
 /* A substitute for POSIX 2008 <stddef.h>, for platforms that have issues.
 
-   Copyright (C) 2009-2013 Free Software Foundation, Inc.
+   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 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 program is distributed in the hope that it will be useful,
+   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 General Public License for more details.
+   GNU Lesser 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/>.  */
+   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.
- * <http://www.opengroup.org/susv3xbd/stddef.h.html>
+ * <https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/stddef.h.html>
  */
 
 #if __GNUC__ >= 3
@@ -39,10 +39,16 @@
 
 # if !(defined _@GUARD_PREFIX@_STDDEF_H && defined _GL_STDDEF_WINT_T)
 #  ifdef __need_wint_t
-#   undef _@GUARD_PREFIX@_STDDEF_H
 #   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
@@ -50,37 +56,92 @@
 
 # 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@
 
-#  ifndef _@GUARD_PREFIX@_STDDEF_H
-#   define _@GUARD_PREFIX@_STDDEF_H
-
 /* On NetBSD 5.0, the definition of NULL lacks proper parentheses.  */
-#if @REPLACE_NULL@
-# undef NULL
-# ifdef __cplusplus
+#  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
+#    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
+#     define NULL __null
+#    else
+#     define NULL 0L
+#    endif
+#   else
+#    define NULL ((void *) 0)
+#   endif
 #  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 */