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Diffstat (limited to 'include/lib/stdlib/sys/cdefs.h')
-rw-r--r--include/lib/stdlib/sys/cdefs.h686
1 files changed, 686 insertions, 0 deletions
diff --git a/include/lib/stdlib/sys/cdefs.h b/include/lib/stdlib/sys/cdefs.h
new file mode 100644
index 000000000..16fb15190
--- /dev/null
+++ b/include/lib/stdlib/sys/cdefs.h
@@ -0,0 +1,686 @@
+/*-
+ * Copyright (c) 1991, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Berkeley Software Design, Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * @(#)cdefs.h 8.8 (Berkeley) 1/9/95
+ * $FreeBSD$
+ */
+
+#ifndef _SYS_CDEFS_H_
+#define _SYS_CDEFS_H_
+
+#if defined(__cplusplus)
+#define __BEGIN_DECLS extern "C" {
+#define __END_DECLS }
+#else
+#define __BEGIN_DECLS
+#define __END_DECLS
+#endif
+
+/*
+ * This code has been put in place to help reduce the addition of
+ * compiler specific defines in FreeBSD code. It helps to aid in
+ * having a compiler-agnostic source tree.
+ */
+
+#if defined(__GNUC__) || defined(__INTEL_COMPILER)
+
+#if __GNUC__ >= 3 || defined(__INTEL_COMPILER)
+#define __GNUCLIKE_ASM 3
+#define __GNUCLIKE_MATH_BUILTIN_CONSTANTS
+#else
+#define __GNUCLIKE_ASM 2
+#endif
+#define __GNUCLIKE___TYPEOF 1
+#define __GNUCLIKE___OFFSETOF 1
+#define __GNUCLIKE___SECTION 1
+
+#ifndef __INTEL_COMPILER
+# define __GNUCLIKE_CTOR_SECTION_HANDLING 1
+#endif
+
+#define __GNUCLIKE_BUILTIN_CONSTANT_P 1
+# if defined(__INTEL_COMPILER) && defined(__cplusplus) \
+ && __INTEL_COMPILER < 800
+# undef __GNUCLIKE_BUILTIN_CONSTANT_P
+# endif
+
+#if (__GNUC_MINOR__ > 95 || __GNUC__ >= 3) && !defined(__INTEL_COMPILER)
+# define __GNUCLIKE_BUILTIN_VARARGS 1
+# define __GNUCLIKE_BUILTIN_STDARG 1
+# define __GNUCLIKE_BUILTIN_VAALIST 1
+#endif
+
+#if defined(__GNUC__)
+# define __GNUC_VA_LIST_COMPATIBILITY 1
+#endif
+
+#ifndef __INTEL_COMPILER
+# define __GNUCLIKE_BUILTIN_NEXT_ARG 1
+# define __GNUCLIKE_MATH_BUILTIN_RELOPS
+#endif
+
+#define __GNUCLIKE_BUILTIN_MEMCPY 1
+
+/* XXX: if __GNUC__ >= 2: not tested everywhere originally, where replaced */
+#define __CC_SUPPORTS_INLINE 1
+#define __CC_SUPPORTS___INLINE 1
+#define __CC_SUPPORTS___INLINE__ 1
+
+#define __CC_SUPPORTS___FUNC__ 1
+#define __CC_SUPPORTS_WARNING 1
+
+#define __CC_SUPPORTS_VARADIC_XXX 1 /* see varargs.h */
+
+#define __CC_SUPPORTS_DYNAMIC_ARRAY_INIT 1
+
+#endif /* __GNUC__ || __INTEL_COMPILER */
+
+/*
+ * Macro to test if we're using a specific version of gcc or later.
+ */
+#if defined(__GNUC__) && !defined(__INTEL_COMPILER)
+#define __GNUC_PREREQ__(ma, mi) \
+ (__GNUC__ > (ma) || __GNUC__ == (ma) && __GNUC_MINOR__ >= (mi))
+#else
+#define __GNUC_PREREQ__(ma, mi) 0
+#endif
+
+/*
+ * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
+ * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
+ * The __CONCAT macro is a bit tricky to use if it must work in non-ANSI
+ * mode -- there must be no spaces between its arguments, and for nested
+ * __CONCAT's, all the __CONCAT's must be at the left. __CONCAT can also
+ * concatenate double-quoted strings produced by the __STRING macro, but
+ * this only works with ANSI C.
+ *
+ * __XSTRING is like __STRING, but it expands any macros in its argument
+ * first. It is only available with ANSI C.
+ */
+#if defined(__STDC__) || defined(__cplusplus)
+#define __P(protos) protos /* full-blown ANSI C */
+#define __CONCAT1(x,y) x ## y
+#define __CONCAT(x,y) __CONCAT1(x,y)
+#define __STRING(x) #x /* stringify without expanding x */
+#define __XSTRING(x) __STRING(x) /* expand x, then stringify */
+
+#define __const const /* define reserved names to standard */
+#define __signed signed
+#define __volatile volatile
+#if defined(__cplusplus)
+#define __inline inline /* convert to C++ keyword */
+#else
+#if !(defined(__CC_SUPPORTS___INLINE))
+#define __inline /* delete GCC keyword */
+#endif /* ! __CC_SUPPORTS___INLINE */
+#endif /* !__cplusplus */
+
+#else /* !(__STDC__ || __cplusplus) */
+#define __P(protos) () /* traditional C preprocessor */
+#define __CONCAT(x,y) x/**/y
+#define __STRING(x) "x"
+
+#if !defined(__CC_SUPPORTS___INLINE)
+#define __const /* delete pseudo-ANSI C keywords */
+#define __inline
+#define __signed
+#define __volatile
+/*
+ * In non-ANSI C environments, new programs will want ANSI-only C keywords
+ * deleted from the program and old programs will want them left alone.
+ * When using a compiler other than gcc, programs using the ANSI C keywords
+ * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS.
+ * When using "gcc -traditional", we assume that this is the intent; if
+ * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone.
+ */
+#ifndef NO_ANSI_KEYWORDS
+#define const /* delete ANSI C keywords */
+#define inline
+#define signed
+#define volatile
+#endif /* !NO_ANSI_KEYWORDS */
+#endif /* !__CC_SUPPORTS___INLINE */
+#endif /* !(__STDC__ || __cplusplus) */
+
+/*
+ * Compiler-dependent macros to help declare dead (non-returning) and
+ * pure (no side effects) functions, and unused variables. They are
+ * null except for versions of gcc that are known to support the features
+ * properly (old versions of gcc-2 supported the dead and pure features
+ * in a different (wrong) way). If we do not provide an implementation
+ * for a given compiler, let the compile fail if it is told to use
+ * a feature that we cannot live without.
+ */
+#ifdef lint
+#define __dead2
+#define __pure2
+#define __unused
+#define __packed
+#define __aligned(x)
+#define __section(x)
+#else
+#if !__GNUC_PREREQ__(2, 5) && !defined(__INTEL_COMPILER)
+#define __dead2
+#define __pure2
+#define __unused
+#endif
+#if __GNUC__ == 2 && __GNUC_MINOR__ >= 5 && __GNUC_MINOR__ < 7 && !defined(__INTEL_COMPILER)
+#define __dead2 __attribute__((__noreturn__))
+#define __pure2 __attribute__((__const__))
+#define __unused
+/* XXX Find out what to do for __packed, __aligned and __section */
+#endif
+#if __GNUC_PREREQ__(2, 7)
+#define __dead2 __attribute__((__noreturn__))
+#define __pure2 __attribute__((__const__))
+#define __unused __attribute__((__unused__))
+#define __used __attribute__((__used__))
+#define __packed __attribute__((__packed__))
+#define __aligned(x) __attribute__((__aligned__(x)))
+#define __section(x) __attribute__((__section__(x)))
+#endif
+#if defined(__INTEL_COMPILER)
+#define __dead2 __attribute__((__noreturn__))
+#define __pure2 __attribute__((__const__))
+#define __unused __attribute__((__unused__))
+#define __used __attribute__((__used__))
+#define __packed __attribute__((__packed__))
+#define __aligned(x) __attribute__((__aligned__(x)))
+#define __section(x) __attribute__((__section__(x)))
+#endif
+#endif
+
+#if !__GNUC_PREREQ__(2, 95)
+#define __alignof(x) __offsetof(struct { char __a; x __b; }, __b)
+#endif
+
+/*
+ * Keywords added in C11.
+ */
+#if defined(__cplusplus) && __cplusplus >= 201103L
+#define _Alignas(e) alignas(e)
+#define _Alignof(e) alignof(e)
+#define _Noreturn [[noreturn]]
+#define _Static_assert(e, s) static_assert(e, s)
+/* FIXME: change this to thread_local when clang in base supports it */
+#define _Thread_local __thread
+#elif defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
+/* Do nothing. They are language keywords. */
+#else
+/* Not supported. Implement them using our versions. */
+#define _Alignas(x) __aligned(x)
+#define _Alignof(x) __alignof(x)
+#define _Noreturn __dead2
+#define _Thread_local __thread
+#ifdef __COUNTER__
+#define _Static_assert(x, y) __Static_assert(x, __COUNTER__)
+#define __Static_assert(x, y) ___Static_assert(x, y)
+#define ___Static_assert(x, y) typedef char __assert_ ## y[(x) ? 1 : -1]
+#else
+#define _Static_assert(x, y) struct __hack
+#endif
+#endif
+
+/*
+ * Emulation of C11 _Generic(). Unlike the previously defined C11
+ * keywords, it is not possible to implement this using exactly the same
+ * syntax. Therefore implement something similar under the name
+ * __generic(). Unlike _Generic(), this macro can only distinguish
+ * between a single type, so it requires nested invocations to
+ * distinguish multiple cases.
+ */
+
+#if defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L
+#define __generic(expr, t, yes, no) \
+ _Generic(expr, t: yes, default: no)
+#elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus)
+#define __generic(expr, t, yes, no) \
+ __builtin_choose_expr( \
+ __builtin_types_compatible_p(__typeof(expr), t), yes, no)
+#endif
+
+#if __GNUC_PREREQ__(2, 96)
+#define __malloc_like __attribute__((__malloc__))
+#define __pure __attribute__((__pure__))
+#else
+#define __malloc_like
+#define __pure
+#endif
+
+#if __GNUC_PREREQ__(3, 1) || (defined(__INTEL_COMPILER) && __INTEL_COMPILER >= 800)
+#define __always_inline __attribute__((__always_inline__))
+#else
+#define __always_inline
+#endif
+
+#if __GNUC_PREREQ__(3, 1)
+#define __noinline __attribute__ ((__noinline__))
+#else
+#define __noinline
+#endif
+
+#if __GNUC_PREREQ__(3, 3)
+#define __nonnull(x) __attribute__((__nonnull__(x)))
+#else
+#define __nonnull(x)
+#endif
+
+#if __GNUC_PREREQ__(3, 4)
+#define __fastcall __attribute__((__fastcall__))
+#else
+#define __fastcall
+#endif
+
+#if __GNUC_PREREQ__(4, 1)
+#define __returns_twice __attribute__((__returns_twice__))
+#else
+#define __returns_twice
+#endif
+
+/* XXX: should use `#if __STDC_VERSION__ < 199901'. */
+#if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER)
+#define __func__ NULL
+#endif
+
+#if (defined(__INTEL_COMPILER) || (defined(__GNUC__) && __GNUC__ >= 2)) && !defined(__STRICT_ANSI__) || __STDC_VERSION__ >= 199901
+#define __LONG_LONG_SUPPORTED
+#endif
+
+/* C++11 exposes a load of C99 stuff */
+#if defined(__cplusplus) && __cplusplus >= 201103L
+#define __LONG_LONG_SUPPORTED
+#ifndef __STDC_LIMIT_MACROS
+#define __STDC_LIMIT_MACROS
+#endif
+#ifndef __STDC_CONSTANT_MACROS
+#define __STDC_CONSTANT_MACROS
+#endif
+#endif
+
+/*
+ * GCC 2.95 provides `__restrict' as an extension to C90 to support the
+ * C99-specific `restrict' type qualifier. We happen to use `__restrict' as
+ * a way to define the `restrict' type qualifier without disturbing older
+ * software that is unaware of C99 keywords.
+ */
+#if !(__GNUC__ == 2 && __GNUC_MINOR__ == 95)
+#if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 199901 || defined(lint)
+#define __restrict
+#else
+#define __restrict restrict
+#endif
+#endif
+
+/*
+ * GNU C version 2.96 adds explicit branch prediction so that
+ * the CPU back-end can hint the processor and also so that
+ * code blocks can be reordered such that the predicted path
+ * sees a more linear flow, thus improving cache behavior, etc.
+ *
+ * The following two macros provide us with a way to utilize this
+ * compiler feature. Use __predict_true() if you expect the expression
+ * to evaluate to true, and __predict_false() if you expect the
+ * expression to evaluate to false.
+ *
+ * A few notes about usage:
+ *
+ * * Generally, __predict_false() error condition checks (unless
+ * you have some _strong_ reason to do otherwise, in which case
+ * document it), and/or __predict_true() `no-error' condition
+ * checks, assuming you want to optimize for the no-error case.
+ *
+ * * Other than that, if you don't know the likelihood of a test
+ * succeeding from empirical or other `hard' evidence, don't
+ * make predictions.
+ *
+ * * These are meant to be used in places that are run `a lot'.
+ * It is wasteful to make predictions in code that is run
+ * seldomly (e.g. at subsystem initialization time) as the
+ * basic block reordering that this affects can often generate
+ * larger code.
+ */
+#if __GNUC_PREREQ__(2, 96)
+#define __predict_true(exp) __builtin_expect((exp), 1)
+#define __predict_false(exp) __builtin_expect((exp), 0)
+#else
+#define __predict_true(exp) (exp)
+#define __predict_false(exp) (exp)
+#endif
+
+#if __GNUC_PREREQ__(4, 2)
+#define __hidden __attribute__((__visibility__("hidden")))
+#define __exported __attribute__((__visibility__("default")))
+#else
+#define __hidden
+#define __exported
+#endif
+
+/*
+ * We define this here since <stddef.h>, <sys/queue.h>, and <sys/types.h>
+ * require it.
+ */
+#if __GNUC_PREREQ__(4, 1)
+#define __offsetof(type, field) __builtin_offsetof(type, field)
+#else
+#ifndef __cplusplus
+#define __offsetof(type, field) \
+ ((__size_t)(__uintptr_t)((const volatile void *)&((type *)0)->field))
+#else
+#define __offsetof(type, field) \
+ (__offsetof__ (reinterpret_cast <__size_t> \
+ (&reinterpret_cast <const volatile char &> \
+ (static_cast<type *> (0)->field))))
+#endif
+#endif
+#define __rangeof(type, start, end) \
+ (__offsetof(type, end) - __offsetof(type, start))
+
+/*
+ * Given the pointer x to the member m of the struct s, return
+ * a pointer to the containing structure. When using GCC, we first
+ * assign pointer x to a local variable, to check that its type is
+ * compatible with member m.
+ */
+#if __GNUC_PREREQ__(3, 1)
+#define __containerof(x, s, m) ({ \
+ const volatile __typeof(((s *)0)->m) *__x = (x); \
+ __DEQUALIFY(s *, (const volatile char *)__x - __offsetof(s, m));\
+})
+#else
+#define __containerof(x, s, m) \
+ __DEQUALIFY(s *, (const volatile char *)(x) - __offsetof(s, m))
+#endif
+
+/*
+ * Compiler-dependent macros to declare that functions take printf-like
+ * or scanf-like arguments. They are null except for versions of gcc
+ * that are known to support the features properly (old versions of gcc-2
+ * didn't permit keeping the keywords out of the application namespace).
+ */
+#if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER)
+#define __printflike(fmtarg, firstvararg)
+#define __scanflike(fmtarg, firstvararg)
+#define __format_arg(fmtarg)
+#define __strfmonlike(fmtarg, firstvararg)
+#define __strftimelike(fmtarg, firstvararg)
+#else
+#define __printflike(fmtarg, firstvararg) \
+ __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
+#define __scanflike(fmtarg, firstvararg) \
+ __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
+#define __format_arg(fmtarg) __attribute__((__format_arg__ (fmtarg)))
+#define __strfmonlike(fmtarg, firstvararg) \
+ __attribute__((__format__ (__strfmon__, fmtarg, firstvararg)))
+#define __strftimelike(fmtarg, firstvararg) \
+ __attribute__((__format__ (__strftime__, fmtarg, firstvararg)))
+#endif
+
+/* Compiler-dependent macros that rely on FreeBSD-specific extensions. */
+#if __FreeBSD_cc_version >= 300001 && defined(__GNUC__) && !defined(__INTEL_COMPILER)
+#define __printf0like(fmtarg, firstvararg) \
+ __attribute__((__format__ (__printf0__, fmtarg, firstvararg)))
+#else
+#define __printf0like(fmtarg, firstvararg)
+#endif
+
+#if defined(__GNUC__) || defined(__INTEL_COMPILER)
+#ifndef __INTEL_COMPILER
+#define __strong_reference(sym,aliassym) \
+ extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym)))
+#endif
+#ifdef __STDC__
+#define __weak_reference(sym,alias) \
+ __asm__(".weak " #alias); \
+ __asm__(".equ " #alias ", " #sym)
+#define __warn_references(sym,msg) \
+ __asm__(".section .gnu.warning." #sym); \
+ __asm__(".asciz \"" msg "\""); \
+ __asm__(".previous")
+#define __sym_compat(sym,impl,verid) \
+ __asm__(".symver " #impl ", " #sym "@" #verid)
+#define __sym_default(sym,impl,verid) \
+ __asm__(".symver " #impl ", " #sym "@@" #verid)
+#else
+#define __weak_reference(sym,alias) \
+ __asm__(".weak alias"); \
+ __asm__(".equ alias, sym")
+#define __warn_references(sym,msg) \
+ __asm__(".section .gnu.warning.sym"); \
+ __asm__(".asciz \"msg\""); \
+ __asm__(".previous")
+#define __sym_compat(sym,impl,verid) \
+ __asm__(".symver impl, sym@verid")
+#define __sym_default(impl,sym,verid) \
+ __asm__(".symver impl, sym@@verid")
+#endif /* __STDC__ */
+#endif /* __GNUC__ || __INTEL_COMPILER */
+
+#define __GLOBL1(sym) __asm__(".globl " #sym)
+#define __GLOBL(sym) __GLOBL1(sym)
+
+#if defined(__GNUC__) || defined(__INTEL_COMPILER)
+#define __IDSTRING(name,string) __asm__(".ident\t\"" string "\"")
+#else
+/*
+ * The following definition might not work well if used in header files,
+ * but it should be better than nothing. If you want a "do nothing"
+ * version, then it should generate some harmless declaration, such as:
+ * #define __IDSTRING(name,string) struct __hack
+ */
+#define __IDSTRING(name,string) static const char name[] __unused = string
+#endif
+
+/*
+ * Embed the rcs id of a source file in the resulting library. Note that in
+ * more recent ELF binutils, we use .ident allowing the ID to be stripped.
+ * Usage:
+ * __FBSDID("$FreeBSD$");
+ */
+#ifndef __FBSDID
+#if !defined(lint) && !defined(STRIP_FBSDID)
+#define __FBSDID(s) __IDSTRING(__CONCAT(__rcsid_,__LINE__),s)
+#else
+#define __FBSDID(s) struct __hack
+#endif
+#endif
+
+#ifndef __RCSID
+#ifndef NO__RCSID
+#define __RCSID(s) __IDSTRING(__CONCAT(__rcsid_,__LINE__),s)
+#else
+#define __RCSID(s) struct __hack
+#endif
+#endif
+
+#ifndef __RCSID_SOURCE
+#ifndef NO__RCSID_SOURCE
+#define __RCSID_SOURCE(s) __IDSTRING(__CONCAT(__rcsid_source_,__LINE__),s)
+#else
+#define __RCSID_SOURCE(s) struct __hack
+#endif
+#endif
+
+#ifndef __SCCSID
+#ifndef NO__SCCSID
+#define __SCCSID(s) __IDSTRING(__CONCAT(__sccsid_,__LINE__),s)
+#else
+#define __SCCSID(s) struct __hack
+#endif
+#endif
+
+#ifndef __COPYRIGHT
+#ifndef NO__COPYRIGHT
+#define __COPYRIGHT(s) __IDSTRING(__CONCAT(__copyright_,__LINE__),s)
+#else
+#define __COPYRIGHT(s) struct __hack
+#endif
+#endif
+
+#ifndef __DECONST
+#define __DECONST(type, var) ((type)(__uintptr_t)(const void *)(var))
+#endif
+
+#ifndef __DEVOLATILE
+#define __DEVOLATILE(type, var) ((type)(__uintptr_t)(volatile void *)(var))
+#endif
+
+#ifndef __DEQUALIFY
+#define __DEQUALIFY(type, var) ((type)(__uintptr_t)(const volatile void *)(var))
+#endif
+
+/*-
+ * The following definitions are an extension of the behavior originally
+ * implemented in <sys/_posix.h>, but with a different level of granularity.
+ * POSIX.1 requires that the macros we test be defined before any standard
+ * header file is included.
+ *
+ * Here's a quick run-down of the versions:
+ * defined(_POSIX_SOURCE) 1003.1-1988
+ * _POSIX_C_SOURCE == 1 1003.1-1990
+ * _POSIX_C_SOURCE == 2 1003.2-1992 C Language Binding Option
+ * _POSIX_C_SOURCE == 199309 1003.1b-1993
+ * _POSIX_C_SOURCE == 199506 1003.1c-1995, 1003.1i-1995,
+ * and the omnibus ISO/IEC 9945-1: 1996
+ * _POSIX_C_SOURCE == 200112 1003.1-2001
+ * _POSIX_C_SOURCE == 200809 1003.1-2008
+ *
+ * In addition, the X/Open Portability Guide, which is now the Single UNIX
+ * Specification, defines a feature-test macro which indicates the version of
+ * that specification, and which subsumes _POSIX_C_SOURCE.
+ *
+ * Our macros begin with two underscores to avoid namespace screwage.
+ */
+
+/* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */
+#if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 1
+#undef _POSIX_C_SOURCE /* Probably illegal, but beyond caring now. */
+#define _POSIX_C_SOURCE 199009
+#endif
+
+/* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */
+#if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 2
+#undef _POSIX_C_SOURCE
+#define _POSIX_C_SOURCE 199209
+#endif
+
+/* Deal with various X/Open Portability Guides and Single UNIX Spec. */
+#ifdef _XOPEN_SOURCE
+#if _XOPEN_SOURCE - 0 >= 700
+#define __XSI_VISIBLE 700
+#undef _POSIX_C_SOURCE
+#define _POSIX_C_SOURCE 200809
+#elif _XOPEN_SOURCE - 0 >= 600
+#define __XSI_VISIBLE 600
+#undef _POSIX_C_SOURCE
+#define _POSIX_C_SOURCE 200112
+#elif _XOPEN_SOURCE - 0 >= 500
+#define __XSI_VISIBLE 500
+#undef _POSIX_C_SOURCE
+#define _POSIX_C_SOURCE 199506
+#endif
+#endif
+
+/*
+ * Deal with all versions of POSIX. The ordering relative to the tests above is
+ * important.
+ */
+#if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
+#define _POSIX_C_SOURCE 198808
+#endif
+#ifdef _POSIX_C_SOURCE
+#if _POSIX_C_SOURCE >= 200809
+#define __POSIX_VISIBLE 200809
+#define __ISO_C_VISIBLE 1999
+#elif _POSIX_C_SOURCE >= 200112
+#define __POSIX_VISIBLE 200112
+#define __ISO_C_VISIBLE 1999
+#elif _POSIX_C_SOURCE >= 199506
+#define __POSIX_VISIBLE 199506
+#define __ISO_C_VISIBLE 1990
+#elif _POSIX_C_SOURCE >= 199309
+#define __POSIX_VISIBLE 199309
+#define __ISO_C_VISIBLE 1990
+#elif _POSIX_C_SOURCE >= 199209
+#define __POSIX_VISIBLE 199209
+#define __ISO_C_VISIBLE 1990
+#elif _POSIX_C_SOURCE >= 199009
+#define __POSIX_VISIBLE 199009
+#define __ISO_C_VISIBLE 1990
+#else
+#define __POSIX_VISIBLE 198808
+#define __ISO_C_VISIBLE 0
+#endif /* _POSIX_C_SOURCE */
+#else
+/*-
+ * Deal with _ANSI_SOURCE:
+ * If it is defined, and no other compilation environment is explicitly
+ * requested, then define our internal feature-test macros to zero. This
+ * makes no difference to the preprocessor (undefined symbols in preprocessing
+ * expressions are defined to have value zero), but makes it more convenient for
+ * a test program to print out the values.
+ *
+ * If a program mistakenly defines _ANSI_SOURCE and some other macro such as
+ * _POSIX_C_SOURCE, we will assume that it wants the broader compilation
+ * environment (and in fact we will never get here).
+ */
+#if defined(_ANSI_SOURCE) /* Hide almost everything. */
+#define __POSIX_VISIBLE 0
+#define __XSI_VISIBLE 0
+#define __BSD_VISIBLE 0
+#define __ISO_C_VISIBLE 1990
+#elif defined(_C99_SOURCE) /* Localism to specify strict C99 env. */
+#define __POSIX_VISIBLE 0
+#define __XSI_VISIBLE 0
+#define __BSD_VISIBLE 0
+#define __ISO_C_VISIBLE 1999
+#else /* Default environment: show everything. */
+#define __POSIX_VISIBLE 200809
+#define __XSI_VISIBLE 700
+#define __BSD_VISIBLE 1
+#define __ISO_C_VISIBLE 1999
+#endif
+#endif
+
+#ifndef __has_feature
+#define __has_feature(x) 0
+#endif
+#ifndef __has_include
+#define __has_include(x) 0
+#endif
+#ifndef __has_builtin
+#define __has_builtin(x) 0
+#endif
+
+#if defined(__mips) || defined(__powerpc64__) || defined(__arm__)
+#define __NO_TLS 1
+#endif
+
+#endif /* !_SYS_CDEFS_H_ */