Sync with the latest Gnulib code 668c0b8ffa

1 files changed, 707 insertions, 0 deletions

diff --git a/gl/cdefs.h b/gl/cdefs.h
new file mode 100644
index 0000000..09a3d19
--- /dev/null
+++ b/gl/cdefs.h
@@ -0,0 +1,707 @@
+/* Copyright (C) 1992-2023 Free Software Foundation, Inc.
+   Copyright The GNU Toolchain Authors.
+   This file is part of the GNU C Library.
+
+   The GNU C Library 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.
+
+   The GNU C Library 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 the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#ifndef _SYS_CDEFS_H
+#define _SYS_CDEFS_H    1
+
+/* We are almost always included from features.h. */
+#ifndef _FEATURES_H
+# include <features.h>
+#endif
+
+/* The GNU libc does not support any K&R compilers or the traditional mode
+   of ISO C compilers anymore.  Check for some of the combinations not
+   supported anymore.  */
+#if defined __GNUC__ && !defined __STDC__
+# error "You need a ISO C conforming compiler to use the glibc headers"
+#endif
+
+/* Some user header file might have defined this before.  */
+#undef  __P
+#undef  __PMT
+
+/* Compilers that lack __has_attribute may object to
+       #if defined __has_attribute && __has_attribute (...)
+   even though they do not need to evaluate the right-hand side of the &&.
+   Similarly for __has_builtin, etc.  */
+#if (defined __has_attribute \
+     && (!defined __clang_minor__ \
+         || (defined __apple_build_version__ \
+             ? 6000000 <= __apple_build_version__ \
+             : 3 < __clang_major__ + (5 <= __clang_minor__))))
+# define __glibc_has_attribute(attr) __has_attribute (attr)
+#else
+# define __glibc_has_attribute(attr) 0
+#endif
+#ifdef __has_builtin
+# define __glibc_has_builtin(name) __has_builtin (name)
+#else
+# define __glibc_has_builtin(name) 0
+#endif
+#ifdef __has_extension
+# define __glibc_has_extension(ext) __has_extension (ext)
+#else
+# define __glibc_has_extension(ext) 0
+#endif
+
+#if defined __GNUC__ || defined __clang__
+
+/* All functions, except those with callbacks or those that
+   synchronize memory, are leaf functions.  */
+# if __GNUC_PREREQ (4, 6) && !defined _LIBC
+#  define __LEAF , __leaf__
+#  define __LEAF_ATTR __attribute__ ((__leaf__))
+# else
+#  define __LEAF
+#  define __LEAF_ATTR
+# endif
+
+/* GCC can always grok prototypes.  For C++ programs we add throw()
+   to help it optimize the function calls.  But this only works with
+   gcc 2.8.x and egcs.  For gcc 3.4 and up we even mark C functions
+   as non-throwing using a function attribute since programs can use
+   the -fexceptions options for C code as well.  */
+# if !defined __cplusplus \
+     && (__GNUC_PREREQ (3, 4) || __glibc_has_attribute (__nothrow__))
+#  define __THROW       __attribute__ ((__nothrow__ __LEAF))
+#  define __THROWNL     __attribute__ ((__nothrow__))
+#  define __NTH(fct)    __attribute__ ((__nothrow__ __LEAF)) fct
+#  define __NTHNL(fct)  __attribute__ ((__nothrow__)) fct
+# else
+#  if defined __cplusplus && (__GNUC_PREREQ (2,8) || __clang_major >= 4)
+#   if __cplusplus >= 201103L
+#    define __THROW     noexcept (true)
+#   else
+#    define __THROW     throw ()
+#   endif
+#   define __THROWNL    __THROW
+#   define __NTH(fct)   __LEAF_ATTR fct __THROW
+#   define __NTHNL(fct) fct __THROW
+#  else
+#   define __THROW
+#   define __THROWNL
+#   define __NTH(fct)   fct
+#   define __NTHNL(fct) fct
+#  endif
+# endif
+
+#else   /* Not GCC or clang.  */
+
+# if (defined __cplusplus                                               \
+      || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L))
+#  define __inline      inline
+# else
+#  define __inline              /* No inline functions.  */
+# endif
+
+# define __THROW
+# define __THROWNL
+# define __NTH(fct)     fct
+
+#endif  /* GCC || clang.  */
+
+/* These two macros are not used in glibc anymore.  They are kept here
+   only because some other projects expect the macros to be defined.  */
+#define __P(args)       args
+#define __PMT(args)     args
+
+/* For these things, GCC behaves the ANSI way normally,
+   and the non-ANSI way under -traditional.  */
+
+#define __CONCAT(x,y)   x ## y
+#define __STRING(x)     #x
+
+/* This is not a typedef so `const __ptr_t' does the right thing.  */
+#define __ptr_t void *
+
+
+/* C++ needs to know that types and declarations are C, not C++.  */
+#ifdef  __cplusplus
+# define __BEGIN_DECLS  extern "C" {
+# define __END_DECLS    }
+#else
+# define __BEGIN_DECLS
+# define __END_DECLS
+#endif
+
+
+/* Fortify support.  */
+#define __bos(ptr) __builtin_object_size (ptr, __USE_FORTIFY_LEVEL > 1)
+#define __bos0(ptr) __builtin_object_size (ptr, 0)
+
+/* Use __builtin_dynamic_object_size at _FORTIFY_SOURCE=3 when available.  */
+#if __USE_FORTIFY_LEVEL == 3 && (__glibc_clang_prereq (9, 0)                  \
+                                 || __GNUC_PREREQ (12, 0))
+# define __glibc_objsize0(__o) __builtin_dynamic_object_size (__o, 0)
+# define __glibc_objsize(__o) __builtin_dynamic_object_size (__o, 1)
+#else
+# define __glibc_objsize0(__o) __bos0 (__o)
+# define __glibc_objsize(__o) __bos (__o)
+#endif
+
+/* Compile time conditions to choose between the regular, _chk and _chk_warn
+   variants.  These conditions should get evaluated to constant and optimized
+   away.  */
+
+#define __glibc_safe_len_cond(__l, __s, __osz) ((__l) <= (__osz) / (__s))
+#define __glibc_unsigned_or_positive(__l) \
+  ((__typeof (__l)) 0 < (__typeof (__l)) -1                                   \
+   || (__builtin_constant_p (__l) && (__l) > 0))
+
+/* Length is known to be safe at compile time if the __L * __S <= __OBJSZ
+   condition can be folded to a constant and if it is true, or unknown (-1) */
+#define __glibc_safe_or_unknown_len(__l, __s, __osz) \
+  ((__osz) == (__SIZE_TYPE__) -1                                              \
+   || (__glibc_unsigned_or_positive (__l)                                     \
+       && __builtin_constant_p (__glibc_safe_len_cond ((__SIZE_TYPE__) (__l), \
+                                                       (__s), (__osz)))       \
+       && __glibc_safe_len_cond ((__SIZE_TYPE__) (__l), (__s), (__osz))))
+
+/* Conversely, we know at compile time that the length is unsafe if the
+   __L * __S <= __OBJSZ condition can be folded to a constant and if it is
+   false.  */
+#define __glibc_unsafe_len(__l, __s, __osz) \
+  (__glibc_unsigned_or_positive (__l)                                         \
+   && __builtin_constant_p (__glibc_safe_len_cond ((__SIZE_TYPE__) (__l),     \
+                                                   __s, __osz))               \
+   && !__glibc_safe_len_cond ((__SIZE_TYPE__) (__l), __s, __osz))
+
+/* Fortify function f.  __f_alias, __f_chk and __f_chk_warn must be
+   declared.  */
+
+#define __glibc_fortify(f, __l, __s, __osz, ...) \
+  (__glibc_safe_or_unknown_len (__l, __s, __osz)                              \
+   ? __ ## f ## _alias (__VA_ARGS__)                                          \
+   : (__glibc_unsafe_len (__l, __s, __osz)                                    \
+      ? __ ## f ## _chk_warn (__VA_ARGS__, __osz)                             \
+      : __ ## f ## _chk (__VA_ARGS__, __osz)))                        \
+
+/* Fortify function f, where object size argument passed to f is the number of
+   elements and not total size.  */
+
+#define __glibc_fortify_n(f, __l, __s, __osz, ...) \
+  (__glibc_safe_or_unknown_len (__l, __s, __osz)                              \
+   ? __ ## f ## _alias (__VA_ARGS__)                                          \
+   : (__glibc_unsafe_len (__l, __s, __osz)                                    \
+      ? __ ## f ## _chk_warn (__VA_ARGS__, (__osz) / (__s))                   \
+      : __ ## f ## _chk (__VA_ARGS__, (__osz) / (__s))))                      \
+
+#if __GNUC_PREREQ (4,3)
+# define __warnattr(msg) __attribute__((__warning__ (msg)))
+# define __errordecl(name, msg) \
+  extern void name (void) __attribute__((__error__ (msg)))
+#else
+# define __warnattr(msg)
+# define __errordecl(name, msg) extern void name (void)
+#endif
+
+/* Support for flexible arrays.
+   Headers that should use flexible arrays only if they're "real"
+   (e.g. only if they won't affect sizeof()) should test
+   #if __glibc_c99_flexarr_available.  */
+#if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L && !defined __HP_cc
+# define __flexarr      []
+# define __glibc_c99_flexarr_available 1
+#elif __GNUC_PREREQ (2,97) || defined __clang__
+/* GCC 2.97 and clang support C99 flexible array members as an extension,
+   even when in C89 mode or compiling C++ (any version).  */
+# define __flexarr      []
+# define __glibc_c99_flexarr_available 1
+#elif defined __GNUC__
+/* Pre-2.97 GCC did not support C99 flexible arrays but did have
+   an equivalent extension with slightly different notation.  */
+# define __flexarr      [0]
+# define __glibc_c99_flexarr_available 1
+#else
+/* Some other non-C99 compiler.  Approximate with [1].  */
+# define __flexarr      [1]
+# define __glibc_c99_flexarr_available 0
+#endif
+
+
+/* __asm__ ("xyz") is used throughout the headers to rename functions
+   at the assembly language level.  This is wrapped by the __REDIRECT
+   macro, in order to support compilers that can do this some other
+   way.  When compilers don't support asm-names at all, we have to do
+   preprocessor tricks instead (which don't have exactly the right
+   semantics, but it's the best we can do).
+
+   Example:
+   int __REDIRECT(setpgrp, (__pid_t pid, __pid_t pgrp), setpgid); */
+
+#if (defined __GNUC__ && __GNUC__ >= 2) || (__clang_major__ >= 4)
+
+# define __REDIRECT(name, proto, alias) name proto __asm__ (__ASMNAME (#alias))
+# ifdef __cplusplus
+#  define __REDIRECT_NTH(name, proto, alias) \
+     name proto __THROW __asm__ (__ASMNAME (#alias))
+#  define __REDIRECT_NTHNL(name, proto, alias) \
+     name proto __THROWNL __asm__ (__ASMNAME (#alias))
+# else
+#  define __REDIRECT_NTH(name, proto, alias) \
+     name proto __asm__ (__ASMNAME (#alias)) __THROW
+#  define __REDIRECT_NTHNL(name, proto, alias) \
+     name proto __asm__ (__ASMNAME (#alias)) __THROWNL
+# endif
+# define __ASMNAME(cname)  __ASMNAME2 (__USER_LABEL_PREFIX__, cname)
+# define __ASMNAME2(prefix, cname) __STRING (prefix) cname
+
+/*
+#elif __SOME_OTHER_COMPILER__
+
+# define __REDIRECT(name, proto, alias) name proto; \
+        _Pragma("let " #name " = " #alias)
+*/
+#endif
+
+/* GCC and clang have various useful declarations that can be made with
+   the '__attribute__' syntax.  All of the ways we use this do fine if
+   they are omitted for compilers that don't understand it.  */
+#if !(defined __GNUC__ || defined __clang__)
+# define __attribute__(xyz)     /* Ignore */
+#endif
+
+/* At some point during the gcc 2.96 development the `malloc' attribute
+   for functions was introduced.  We don't want to use it unconditionally
+   (although this would be possible) since it generates warnings.  */
+#if __GNUC_PREREQ (2,96) || __glibc_has_attribute (__malloc__)
+# define __attribute_malloc__ __attribute__ ((__malloc__))
+#else
+# define __attribute_malloc__ /* Ignore */
+#endif
+
+/* Tell the compiler which arguments to an allocation function
+   indicate the size of the allocation.  */
+#if __GNUC_PREREQ (4, 3)
+# define __attribute_alloc_size__(params) \
+  __attribute__ ((__alloc_size__ params))
+#else
+# define __attribute_alloc_size__(params) /* Ignore.  */
+#endif
+
+/* Tell the compiler which argument to an allocation function
+   indicates the alignment of the allocation.  */
+#if __GNUC_PREREQ (4, 9) || __glibc_has_attribute (__alloc_align__)
+# define __attribute_alloc_align__(param) \
+  __attribute__ ((__alloc_align__ param))
+#else
+# define __attribute_alloc_align__(param) /* Ignore.  */
+#endif
+
+/* At some point during the gcc 2.96 development the `pure' attribute
+   for functions was introduced.  We don't want to use it unconditionally
+   (although this would be possible) since it generates warnings.  */
+#if __GNUC_PREREQ (2,96) || __glibc_has_attribute (__pure__)
+# define __attribute_pure__ __attribute__ ((__pure__))
+#else
+# define __attribute_pure__ /* Ignore */
+#endif
+
+/* This declaration tells the compiler that the value is constant.  */
+#if __GNUC_PREREQ (2,5) || __glibc_has_attribute (__const__)
+# define __attribute_const__ __attribute__ ((__const__))
+#else
+# define __attribute_const__ /* Ignore */
+#endif
+
+#if __GNUC_PREREQ (2,7) || __glibc_has_attribute (__unused__)
+# define __attribute_maybe_unused__ __attribute__ ((__unused__))
+#else
+# define __attribute_maybe_unused__ /* Ignore */
+#endif
+
+/* At some point during the gcc 3.1 development the `used' attribute
+   for functions was introduced.  We don't want to use it unconditionally
+   (although this would be possible) since it generates warnings.  */
+#if __GNUC_PREREQ (3,1) || __glibc_has_attribute (__used__)
+# define __attribute_used__ __attribute__ ((__used__))
+# define __attribute_noinline__ __attribute__ ((__noinline__))
+#else
+# define __attribute_used__ __attribute__ ((__unused__))
+# define __attribute_noinline__ /* Ignore */
+#endif
+
+/* Since version 3.2, gcc allows marking deprecated functions.  */
+#if __GNUC_PREREQ (3,2) || __glibc_has_attribute (__deprecated__)
+# define __attribute_deprecated__ __attribute__ ((__deprecated__))
+#else
+# define __attribute_deprecated__ /* Ignore */
+#endif
+
+/* Since version 4.5, gcc also allows one to specify the message printed
+   when a deprecated function is used.  clang claims to be gcc 4.2, but
+   may also support this feature.  */
+#if __GNUC_PREREQ (4,5) \
+    || __glibc_has_extension (__attribute_deprecated_with_message__)
+# define __attribute_deprecated_msg__(msg) \
+         __attribute__ ((__deprecated__ (msg)))
+#else
+# define __attribute_deprecated_msg__(msg) __attribute_deprecated__
+#endif
+
+/* At some point during the gcc 2.8 development the `format_arg' attribute
+   for functions was introduced.  We don't want to use it unconditionally
+   (although this would be possible) since it generates warnings.
+   If several `format_arg' attributes are given for the same function, in
+   gcc-3.0 and older, all but the last one are ignored.  In newer gccs,
+   all designated arguments are considered.  */
+#if __GNUC_PREREQ (2,8) || __glibc_has_attribute (__format_arg__)
+# define __attribute_format_arg__(x) __attribute__ ((__format_arg__ (x)))
+#else
+# define __attribute_format_arg__(x) /* Ignore */
+#endif
+
+/* At some point during the gcc 2.97 development the `strfmon' format
+   attribute for functions was introduced.  We don't want to use it
+   unconditionally (although this would be possible) since it
+   generates warnings.  */
+#if __GNUC_PREREQ (2,97) || __glibc_has_attribute (__format__)
+# define __attribute_format_strfmon__(a,b) \
+  __attribute__ ((__format__ (__strfmon__, a, b)))
+#else
+# define __attribute_format_strfmon__(a,b) /* Ignore */
+#endif
+
+/* The nonnull function attribute marks pointer parameters that
+   must not be NULL.  This has the name __nonnull in glibc,
+   and __attribute_nonnull__ in files shared with Gnulib to avoid
+   collision with a different __nonnull in DragonFlyBSD 5.9.  */
+#ifndef __attribute_nonnull__
+# if __GNUC_PREREQ (3,3) || __glibc_has_attribute (__nonnull__)
+#  define __attribute_nonnull__(params) __attribute__ ((__nonnull__ params))
+# else
+#  define __attribute_nonnull__(params)
+# endif
+#endif
+#ifndef __nonnull
+# define __nonnull(params) __attribute_nonnull__ (params)
+#endif
+
+/* The returns_nonnull function attribute marks the return type of the function
+   as always being non-null.  */
+#ifndef __returns_nonnull
+# if __GNUC_PREREQ (4, 9) || __glibc_has_attribute (__returns_nonnull__)
+# define __returns_nonnull __attribute__ ((__returns_nonnull__))
+# else
+# define __returns_nonnull
+# endif
+#endif
+
+/* If fortification mode, we warn about unused results of certain
+   function calls which can lead to problems.  */
+#if __GNUC_PREREQ (3,4) || __glibc_has_attribute (__warn_unused_result__)
+# define __attribute_warn_unused_result__ \
+   __attribute__ ((__warn_unused_result__))
+# if defined __USE_FORTIFY_LEVEL && __USE_FORTIFY_LEVEL > 0
+#  define __wur __attribute_warn_unused_result__
+# endif
+#else
+# define __attribute_warn_unused_result__ /* empty */
+#endif
+#ifndef __wur
+# define __wur /* Ignore */
+#endif
+
+/* Forces a function to be always inlined.  */
+#if __GNUC_PREREQ (3,2) || __glibc_has_attribute (__always_inline__)
+/* The Linux kernel defines __always_inline in stddef.h (283d7573), and
+   it conflicts with this definition.  Therefore undefine it first to
+   allow either header to be included first.  */
+# undef __always_inline
+# define __always_inline __inline __attribute__ ((__always_inline__))
+#else
+# undef __always_inline
+# define __always_inline __inline
+#endif
+
+/* Associate error messages with the source location of the call site rather
+   than with the source location inside the function.  */
+#if __GNUC_PREREQ (4,3) || __glibc_has_attribute (__artificial__)
+# define __attribute_artificial__ __attribute__ ((__artificial__))
+#else
+# define __attribute_artificial__ /* Ignore */
+#endif
+
+/* GCC 4.3 and above with -std=c99 or -std=gnu99 implements ISO C99
+   inline semantics, unless -fgnu89-inline is used.  Using __GNUC_STDC_INLINE__
+   or __GNUC_GNU_INLINE is not a good enough check for gcc because gcc versions
+   older than 4.3 may define these macros and still not guarantee GNU inlining
+   semantics.
+
+   clang++ identifies itself as gcc-4.2, but has support for GNU inlining
+   semantics, that can be checked for by using the __GNUC_STDC_INLINE_ and
+   __GNUC_GNU_INLINE__ macro definitions.  */
+#if (!defined __cplusplus || __GNUC_PREREQ (4,3) \
+     || (defined __clang__ && (defined __GNUC_STDC_INLINE__ \
+                               || defined __GNUC_GNU_INLINE__)))
+# if defined __GNUC_STDC_INLINE__ || defined __cplusplus
+#  define __extern_inline extern __inline __attribute__ ((__gnu_inline__))
+#  define __extern_always_inline \
+  extern __always_inline __attribute__ ((__gnu_inline__))
+# else
+#  define __extern_inline extern __inline
+#  define __extern_always_inline extern __always_inline
+# endif
+#endif
+
+#ifdef __extern_always_inline
+# define __fortify_function __extern_always_inline __attribute_artificial__
+#endif
+
+/* GCC 4.3 and above allow passing all anonymous arguments of an
+   __extern_always_inline function to some other vararg function.  */
+#if __GNUC_PREREQ (4,3)
+# define __va_arg_pack() __builtin_va_arg_pack ()
+# define __va_arg_pack_len() __builtin_va_arg_pack_len ()
+#endif
+
+/* It is possible to compile containing GCC extensions even if GCC is
+   run in pedantic mode if the uses are carefully marked using the
+   `__extension__' keyword.  But this is not generally available before
+   version 2.8.  */
+#if !(__GNUC_PREREQ (2,8) || defined __clang__)
+# define __extension__          /* Ignore */
+#endif
+
+/* __restrict is known in EGCS 1.2 and above, and in clang.
+   It works also in C++ mode (outside of arrays), but only when spelled
+   as '__restrict', not 'restrict'.  */
+#if !(__GNUC_PREREQ (2,92) || __clang_major__ >= 3)
+# if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
+#  define __restrict    restrict
+# else
+#  define __restrict    /* Ignore */
+# endif
+#endif
+
+/* ISO C99 also allows to declare arrays as non-overlapping.  The syntax is
+     array_name[restrict]
+   GCC 3.1 and clang support this.
+   This syntax is not usable in C++ mode.  */
+#if (__GNUC_PREREQ (3,1) || __clang_major__ >= 3) && !defined __cplusplus
+# define __restrict_arr __restrict
+#else
+# ifdef __GNUC__
+#  define __restrict_arr        /* Not supported in old GCC.  */
+# else
+#  if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
+#   define __restrict_arr       restrict
+#  else
+/* Some other non-C99 compiler.  */
+#   define __restrict_arr       /* Not supported.  */
+#  endif
+# endif
+#endif
+
+#if (__GNUC__ >= 3) || __glibc_has_builtin (__builtin_expect)
+# define __glibc_unlikely(cond) __builtin_expect ((cond), 0)
+# define __glibc_likely(cond)   __builtin_expect ((cond), 1)
+#else
+# define __glibc_unlikely(cond) (cond)
+# define __glibc_likely(cond)   (cond)
+#endif
+
+#if (!defined _Noreturn \
+     && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \
+     &&  !(__GNUC_PREREQ (4,7) \
+           || (3 < __clang_major__ + (5 <= __clang_minor__))))
+# if __GNUC_PREREQ (2,8)
+#  define _Noreturn __attribute__ ((__noreturn__))
+# else
+#  define _Noreturn
+# endif
+#endif
+
+#if __GNUC_PREREQ (8, 0)
+/* Describes a char array whose address can safely be passed as the first
+   argument to strncpy and strncat, as the char array is not necessarily
+   a NUL-terminated string.  */
+# define __attribute_nonstring__ __attribute__ ((__nonstring__))
+#else
+# define __attribute_nonstring__
+#endif
+
+/* Undefine (also defined in libc-symbols.h).  */
+#undef __attribute_copy__
+#if __GNUC_PREREQ (9, 0)
+/* Copies attributes from the declaration or type referenced by
+   the argument.  */
+# define __attribute_copy__(arg) __attribute__ ((__copy__ (arg)))
+#else
+# define __attribute_copy__(arg)
+#endif
+
+#if (!defined _Static_assert && !defined __cplusplus \
+     && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \
+     && (!(__GNUC_PREREQ (4, 6) || __clang_major__ >= 4) \
+         || defined __STRICT_ANSI__))
+# define _Static_assert(expr, diagnostic) \
+    extern int (*__Static_assert_function (void)) \
+      [!!sizeof (struct { int __error_if_negative: (expr) ? 2 : -1; })]
+#endif
+
+/* Gnulib avoids including these, as they don't work on non-glibc or
+   older glibc platforms.  */
+#ifndef __GNULIB_CDEFS
+# include <bits/wordsize.h>
+# include <bits/long-double.h>
+#endif
+
+#if __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 1
+# ifdef __REDIRECT
+
+/* Alias name defined automatically.  */
+#  define __LDBL_REDIR(name, proto) ... unused__ldbl_redir
+#  define __LDBL_REDIR_DECL(name) \
+  extern __typeof (name) name __asm (__ASMNAME ("__" #name "ieee128"));
+
+/* Alias name defined automatically, with leading underscores.  */
+#  define __LDBL_REDIR2_DECL(name) \
+  extern __typeof (__##name) __##name \
+    __asm (__ASMNAME ("__" #name "ieee128"));
+
+/* Alias name defined manually.  */
+#  define __LDBL_REDIR1(name, proto, alias) ... unused__ldbl_redir1
+#  define __LDBL_REDIR1_DECL(name, alias) \
+  extern __typeof (name) name __asm (__ASMNAME (#alias));
+
+#  define __LDBL_REDIR1_NTH(name, proto, alias) \
+  __REDIRECT_NTH (name, proto, alias)
+#  define __REDIRECT_NTH_LDBL(name, proto, alias) \
+  __LDBL_REDIR1_NTH (name, proto, __##alias##ieee128)
+
+/* Unused.  */
+#  define __REDIRECT_LDBL(name, proto, alias) ... unused__redirect_ldbl
+#  define __LDBL_REDIR_NTH(name, proto) ... unused__ldbl_redir_nth
+
+# else
+_Static_assert (0, "IEEE 128-bits long double requires redirection on this platform");
+# endif
+#elif defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
+# define __LDBL_COMPAT 1
+# ifdef __REDIRECT
+#  define __LDBL_REDIR1(name, proto, alias) __REDIRECT (name, proto, alias)
+#  define __LDBL_REDIR(name, proto) \
+  __LDBL_REDIR1 (name, proto, __nldbl_##name)
+#  define __LDBL_REDIR1_NTH(name, proto, alias) __REDIRECT_NTH (name, proto, alias)
+#  define __LDBL_REDIR_NTH(name, proto) \
+  __LDBL_REDIR1_NTH (name, proto, __nldbl_##name)
+#  define __LDBL_REDIR2_DECL(name) \
+  extern __typeof (__##name) __##name __asm (__ASMNAME ("__nldbl___" #name));
+#  define __LDBL_REDIR1_DECL(name, alias) \
+  extern __typeof (name) name __asm (__ASMNAME (#alias));
+#  define __LDBL_REDIR_DECL(name) \
+  extern __typeof (name) name __asm (__ASMNAME ("__nldbl_" #name));
+#  define __REDIRECT_LDBL(name, proto, alias) \
+  __LDBL_REDIR1 (name, proto, __nldbl_##alias)
+#  define __REDIRECT_NTH_LDBL(name, proto, alias) \
+  __LDBL_REDIR1_NTH (name, proto, __nldbl_##alias)
+# endif
+#endif
+#if (!defined __LDBL_COMPAT && __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 0) \
+    || !defined __REDIRECT
+# define __LDBL_REDIR1(name, proto, alias) name proto
+# define __LDBL_REDIR(name, proto) name proto
+# define __LDBL_REDIR1_NTH(name, proto, alias) name proto __THROW
+# define __LDBL_REDIR_NTH(name, proto) name proto __THROW
+# define __LDBL_REDIR2_DECL(name)
+# define __LDBL_REDIR_DECL(name)
+# ifdef __REDIRECT
+#  define __REDIRECT_LDBL(name, proto, alias) __REDIRECT (name, proto, alias)
+#  define __REDIRECT_NTH_LDBL(name, proto, alias) \
+  __REDIRECT_NTH (name, proto, alias)
+# endif
+#endif
+
+/* __glibc_macro_warning (MESSAGE) issues warning MESSAGE.  This is
+   intended for use in preprocessor macros.
+
+   Note: MESSAGE must be a _single_ string; concatenation of string
+   literals is not supported.  */
+#if __GNUC_PREREQ (4,8) || __glibc_clang_prereq (3,5)
+# define __glibc_macro_warning1(message) _Pragma (#message)
+# define __glibc_macro_warning(message) \
+  __glibc_macro_warning1 (GCC warning message)
+#else
+# define __glibc_macro_warning(msg)
+#endif
+
+/* Generic selection (ISO C11) is a C-only feature, available in GCC
+   since version 4.9.  Previous versions do not provide generic
+   selection, even though they might set __STDC_VERSION__ to 201112L,
+   when in -std=c11 mode.  Thus, we must check for !defined __GNUC__
+   when testing __STDC_VERSION__ for generic selection support.
+   On the other hand, Clang also defines __GNUC__, so a clang-specific
+   check is required to enable the use of generic selection.  */
+#if !defined __cplusplus \
+    && (__GNUC_PREREQ (4, 9) \
+        || __glibc_has_extension (c_generic_selections) \
+        || (!defined __GNUC__ && defined __STDC_VERSION__ \
+            && __STDC_VERSION__ >= 201112L))
+# define __HAVE_GENERIC_SELECTION 1
+#else
+# define __HAVE_GENERIC_SELECTION 0
+#endif
+
+#if __GNUC_PREREQ (10, 0)
+/* Designates a 1-based positional argument ref-index of pointer type
+   that can be used to access size-index elements of the pointed-to
+   array according to access mode, or at least one element when
+   size-index is not provided:
+     access (access-mode, <ref-index> [, <size-index>])  */
+#  define __attr_access(x) __attribute__ ((__access__ x))
+/* For _FORTIFY_SOURCE == 3 we use __builtin_dynamic_object_size, which may
+   use the access attribute to get object sizes from function definition
+   arguments, so we can't use them on functions we fortify.  Drop the object
+   size hints for such functions.  */
+#  if __USE_FORTIFY_LEVEL == 3
+#    define __fortified_attr_access(a, o, s) __attribute__ ((__access__ (a, o)))
+#  else
+#    define __fortified_attr_access(a, o, s) __attr_access ((a, o, s))
+#  endif
+#  if __GNUC_PREREQ (11, 0)
+#    define __attr_access_none(argno) __attribute__ ((__access__ (__none__, argno)))
+#  else
+#    define __attr_access_none(argno)
+#  endif
+#else
+#  define __fortified_attr_access(a, o, s)
+#  define __attr_access(x)
+#  define __attr_access_none(argno)
+#endif
+
+#if __GNUC_PREREQ (11, 0)
+/* Designates dealloc as a function to call to deallocate objects
+   allocated by the declared function.  */
+# define __attr_dealloc(dealloc, argno) \
+    __attribute__ ((__malloc__ (dealloc, argno)))
+# define __attr_dealloc_free __attr_dealloc (__builtin_free, 1)
+#else
+# define __attr_dealloc(dealloc, argno)
+# define __attr_dealloc_free
+#endif
+
+/* Specify that a function such as setjmp or vfork may return
+   twice.  */
+#if __GNUC_PREREQ (4, 1)
+# define __attribute_returns_twice__ __attribute__ ((__returns_twice__))
+#else
+# define __attribute_returns_twice__ /* Ignore.  */
+#endif
+
+#endif   /* sys/cdefs.h */