summaryrefslogtreecommitdiffstats
path: root/gl/cdefs.h
diff options
context:
space:
mode:
Diffstat (limited to 'gl/cdefs.h')
-rw-r--r--gl/cdefs.h614
1 files changed, 614 insertions, 0 deletions
diff --git a/gl/cdefs.h b/gl/cdefs.h
new file mode 100644
index 0000000..b883b25
--- /dev/null
+++ b/gl/cdefs.h
@@ -0,0 +1,614 @@
+/* Copyright (C) 1992-2021 Free Software Foundation, Inc.
+ 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__ \
+ || 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)
+# 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
+
+#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
+
+/* 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__))
+/* Once the next version of the C standard comes out, we can
+ do something like the following here:
+ #elif defined __STDC_VERSION__ && 202???L <= __STDC_VERSION__
+ # define __attribute_maybe_unused__ [[__maybe_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
+
+/* 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))
+#else
+# define __attr_access(x)
+#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 */