2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
5 * This code is derived from software contributed to Berkeley by
6 * Berkeley Software Design, Inc.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * @(#)cdefs.h 8.8 (Berkeley) 1/9/95
40 * Testing against Clang-specific extensions.
42 #ifndef __has_attribute
43 #define __has_attribute(x) 0
45 #ifndef __has_extension
46 #define __has_extension __has_feature
49 #define __has_feature(x) 0
52 #define __has_include(x) 0
55 #define __has_builtin(x) 0
58 #if defined(__cplusplus)
59 #define __BEGIN_DECLS extern "C" {
67 * This code has been put in place to help reduce the addition of
68 * compiler specific defines in FreeBSD code. It helps to aid in
69 * having a compiler-agnostic source tree.
72 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
74 #if __GNUC__ >= 3 || defined(__INTEL_COMPILER)
75 #define __GNUCLIKE_ASM 3
76 #define __GNUCLIKE_MATH_BUILTIN_CONSTANTS
78 #define __GNUCLIKE_ASM 2
80 #define __GNUCLIKE___TYPEOF 1
81 #define __GNUCLIKE___OFFSETOF 1
82 #define __GNUCLIKE___SECTION 1
84 #ifndef __INTEL_COMPILER
85 #define __GNUCLIKE_CTOR_SECTION_HANDLING 1
88 #define __GNUCLIKE_BUILTIN_CONSTANT_P 1
89 #if defined(__INTEL_COMPILER) && defined(__cplusplus) && \
90 __INTEL_COMPILER < 800
91 #undef __GNUCLIKE_BUILTIN_CONSTANT_P
94 #if (__GNUC_MINOR__ > 95 || __GNUC__ >= 3)
95 #define __GNUCLIKE_BUILTIN_VARARGS 1
96 #define __GNUCLIKE_BUILTIN_STDARG 1
97 #define __GNUCLIKE_BUILTIN_VAALIST 1
100 #if defined(__GNUC__)
101 #define __GNUC_VA_LIST_COMPATIBILITY 1
105 * Compiler memory barriers, specific to gcc and clang.
107 #if defined(__GNUC__)
108 #define __compiler_membar() __asm __volatile(" " : : : "memory")
111 #ifndef __INTEL_COMPILER
112 #define __GNUCLIKE_BUILTIN_NEXT_ARG 1
113 #define __GNUCLIKE_MATH_BUILTIN_RELOPS
116 #define __GNUCLIKE_BUILTIN_MEMCPY 1
118 /* XXX: if __GNUC__ >= 2: not tested everywhere originally, where replaced */
119 #define __CC_SUPPORTS_INLINE 1
120 #define __CC_SUPPORTS___INLINE 1
121 #define __CC_SUPPORTS___INLINE__ 1
123 #define __CC_SUPPORTS___FUNC__ 1
124 #define __CC_SUPPORTS_WARNING 1
126 #define __CC_SUPPORTS_VARADIC_XXX 1 /* see varargs.h */
128 #define __CC_SUPPORTS_DYNAMIC_ARRAY_INIT 1
130 #endif /* __GNUC__ || __INTEL_COMPILER */
133 * Macro to test if we're using a specific version of gcc or later.
135 #if defined(__GNUC__) && !defined(__INTEL_COMPILER)
136 #define __GNUC_PREREQ__(ma, mi) \
137 (__GNUC__ > (ma) || __GNUC__ == (ma) && __GNUC_MINOR__ >= (mi))
139 #define __GNUC_PREREQ__(ma, mi) 0
143 * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
144 * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
145 * The __CONCAT macro is a bit tricky to use if it must work in non-ANSI
146 * mode -- there must be no spaces between its arguments, and for nested
147 * __CONCAT's, all the __CONCAT's must be at the left. __CONCAT can also
148 * concatenate double-quoted strings produced by the __STRING macro, but
149 * this only works with ANSI C.
151 * __XSTRING is like __STRING, but it expands any macros in its argument
152 * first. It is only available with ANSI C.
154 #if defined(__STDC__) || defined(__cplusplus)
155 #define __P(protos) protos /* full-blown ANSI C */
156 #define __CONCAT1(x,y) x ## y
157 #define __CONCAT(x,y) __CONCAT1(x,y)
158 #define __STRING(x) #x /* stringify without expanding x */
159 #define __XSTRING(x) __STRING(x) /* expand x, then stringify */
161 #define __const const /* define reserved names to standard */
162 #define __signed signed
163 #define __volatile volatile
164 #if defined(__cplusplus)
165 #define __inline inline /* convert to C++ keyword */
167 #if !(defined(__CC_SUPPORTS___INLINE))
168 #define __inline /* delete GCC keyword */
169 #endif /* ! __CC_SUPPORTS___INLINE */
170 #endif /* !__cplusplus */
172 #else /* !(__STDC__ || __cplusplus) */
173 #define __P(protos) () /* traditional C preprocessor */
174 #define __CONCAT(x,y) x/**/y
175 #define __STRING(x) "x"
177 #if !defined(__CC_SUPPORTS___INLINE)
178 #define __const /* delete pseudo-ANSI C keywords */
183 * In non-ANSI C environments, new programs will want ANSI-only C keywords
184 * deleted from the program and old programs will want them left alone.
185 * When using a compiler other than gcc, programs using the ANSI C keywords
186 * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS.
187 * When using "gcc -traditional", we assume that this is the intent; if
188 * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone.
190 #ifndef NO_ANSI_KEYWORDS
191 #define const /* delete ANSI C keywords */
195 #endif /* !NO_ANSI_KEYWORDS */
196 #endif /* !__CC_SUPPORTS___INLINE */
197 #endif /* !(__STDC__ || __cplusplus) */
200 * Compiler-dependent macros to help declare dead (non-returning) and
201 * pure (no side effects) functions, and unused variables. They are
202 * null except for versions of gcc that are known to support the features
203 * properly (old versions of gcc-2 supported the dead and pure features
204 * in a different (wrong) way). If we do not provide an implementation
205 * for a given compiler, let the compile fail if it is told to use
206 * a feature that we cannot live without.
214 #define __alloc_align(x)
215 #define __alloc_size(x)
216 #define __alloc_size2(n, x)
218 #define __weak_symbol
220 #define __weak_symbol __attribute__((__weak__))
221 #if !__GNUC_PREREQ__(2, 5) && !defined(__INTEL_COMPILER)
226 #if __GNUC__ == 2 && __GNUC_MINOR__ >= 5 && __GNUC_MINOR__ < 7 && !defined(__INTEL_COMPILER)
227 #define __dead2 __attribute__((__noreturn__))
228 #define __pure2 __attribute__((__const__))
230 /* XXX Find out what to do for __packed, __aligned and __section */
232 #if __GNUC_PREREQ__(2, 7) || defined(__INTEL_COMPILER)
233 #define __dead2 __attribute__((__noreturn__))
234 #define __pure2 __attribute__((__const__))
235 #define __unused __attribute__((__unused__))
236 #define __used __attribute__((__used__))
237 #define __packed __attribute__((__packed__))
238 #define __aligned(x) __attribute__((__aligned__(x)))
239 #define __section(x) __attribute__((__section__(x)))
241 #if __GNUC_PREREQ__(4, 3) || __has_attribute(__alloc_size__)
242 #define __alloc_size(x) __attribute__((__alloc_size__(x)))
243 #define __alloc_size2(n, x) __attribute__((__alloc_size__(n, x)))
245 #define __alloc_size(x)
246 #define __alloc_size2(n, x)
248 #if __GNUC_PREREQ__(4, 9) || __has_attribute(__alloc_align__)
249 #define __alloc_align(x) __attribute__((__alloc_align__(x)))
251 #define __alloc_align(x)
255 #if !__GNUC_PREREQ__(2, 95)
256 #define __alignof(x) __offsetof(struct { char __a; x __b; }, __b)
260 * Keywords added in C11.
263 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L || defined(lint)
265 #if !__has_extension(c_alignas)
266 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
267 __has_extension(cxx_alignas)
268 #define _Alignas(x) alignas(x)
270 /* XXX: Only emulates _Alignas(constant-expression); not _Alignas(type-name). */
271 #define _Alignas(x) __aligned(x)
275 #if defined(__cplusplus) && __cplusplus >= 201103L
276 #define _Alignof(x) alignof(x)
278 #define _Alignof(x) __alignof(x)
281 #if !defined(__cplusplus) && !__has_extension(c_atomic) && \
282 !__has_extension(cxx_atomic)
284 * No native support for _Atomic(). Place object in structure to prevent
285 * most forms of direct non-atomic access.
287 #define _Atomic(T) struct { T volatile __val; }
290 #if defined(__cplusplus) && __cplusplus >= 201103L
291 #define _Noreturn [[noreturn]]
293 #define _Noreturn __dead2
296 #if !__has_extension(c_static_assert)
297 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
298 __has_extension(cxx_static_assert)
299 #define _Static_assert(x, y) static_assert(x, y)
300 #elif __GNUC_PREREQ__(4,6) && !defined(__cplusplus)
301 /* Nothing, gcc 4.6 and higher has _Static_assert built-in */
302 #elif defined(__COUNTER__)
303 #define _Static_assert(x, y) __Static_assert(x, __COUNTER__)
304 #define __Static_assert(x, y) ___Static_assert(x, y)
305 #define ___Static_assert(x, y) typedef char __assert_ ## y[(x) ? 1 : -1] \
308 #define _Static_assert(x, y) struct __hack
312 #if !__has_extension(c_thread_local)
314 * XXX: Some compilers (Clang 3.3, GCC 4.7) falsely announce C++11 mode
315 * without actually supporting the thread_local keyword. Don't check for
316 * the presence of C++11 when defining _Thread_local.
318 #if /* (defined(__cplusplus) && __cplusplus >= 201103L) || */ \
319 __has_extension(cxx_thread_local)
320 #define _Thread_local thread_local
322 #define _Thread_local __thread
326 #endif /* __STDC_VERSION__ || __STDC_VERSION__ < 201112L */
329 * Emulation of C11 _Generic(). Unlike the previously defined C11
330 * keywords, it is not possible to implement this using exactly the same
331 * syntax. Therefore implement something similar under the name
332 * __generic(). Unlike _Generic(), this macro can only distinguish
333 * between a single type, so it requires nested invocations to
334 * distinguish multiple cases.
337 #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) || \
338 __has_extension(c_generic_selections)
339 #define __generic(expr, t, yes, no) \
340 _Generic(expr, t: yes, default: no)
341 #elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus)
342 #define __generic(expr, t, yes, no) \
343 __builtin_choose_expr( \
344 __builtin_types_compatible_p(__typeof(expr), t), yes, no)
348 * C99 Static array indices in function parameter declarations. Syntax such as:
349 * void bar(int myArray[static 10]);
350 * is allowed in C99 but not in C++. Define __min_size appropriately so
351 * headers using it can be compiled in either language. Use like this:
352 * void bar(int myArray[__min_size(10)]);
354 #if !defined(__cplusplus) && \
355 (defined(__clang__) || __GNUC_PREREQ__(4, 6)) && \
356 (!defined(__STDC_VERSION__) || (__STDC_VERSION__ >= 199901))
357 #define __min_size(x) static (x)
359 #define __min_size(x) (x)
362 #if __GNUC_PREREQ__(2, 96)
363 #define __malloc_like __attribute__((__malloc__))
364 #define __pure __attribute__((__pure__))
366 #define __malloc_like
370 #if __GNUC_PREREQ__(3, 1) || (defined(__INTEL_COMPILER) && __INTEL_COMPILER >= 800)
371 #define __always_inline __attribute__((__always_inline__))
373 #define __always_inline
376 #if __GNUC_PREREQ__(3, 1)
377 #define __noinline __attribute__ ((__noinline__))
382 #if __GNUC_PREREQ__(3, 4)
383 #define __fastcall __attribute__((__fastcall__))
384 #define __result_use_check __attribute__((__warn_unused_result__))
387 #define __result_use_check
390 #if __GNUC_PREREQ__(4, 1)
391 #define __returns_twice __attribute__((__returns_twice__))
393 #define __returns_twice
396 #if __GNUC_PREREQ__(4, 6) || __has_builtin(__builtin_unreachable)
397 #define __unreachable() __builtin_unreachable()
399 #define __unreachable() ((void)0)
402 /* XXX: should use `#if __STDC_VERSION__ < 199901'. */
403 #if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER)
404 #define __func__ NULL
407 #if (defined(__INTEL_COMPILER) || (defined(__GNUC__) && __GNUC__ >= 2)) && !defined(__STRICT_ANSI__) || __STDC_VERSION__ >= 199901
408 #define __LONG_LONG_SUPPORTED
411 /* C++11 exposes a load of C99 stuff */
412 #if defined(__cplusplus) && __cplusplus >= 201103L
413 #define __LONG_LONG_SUPPORTED
414 #ifndef __STDC_LIMIT_MACROS
415 #define __STDC_LIMIT_MACROS
417 #ifndef __STDC_CONSTANT_MACROS
418 #define __STDC_CONSTANT_MACROS
423 * GCC 2.95 provides `__restrict' as an extension to C90 to support the
424 * C99-specific `restrict' type qualifier. We happen to use `__restrict' as
425 * a way to define the `restrict' type qualifier without disturbing older
426 * software that is unaware of C99 keywords.
428 #if !(__GNUC__ == 2 && __GNUC_MINOR__ == 95)
429 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 199901 || defined(lint)
432 #define __restrict restrict
437 * GNU C version 2.96 adds explicit branch prediction so that
438 * the CPU back-end can hint the processor and also so that
439 * code blocks can be reordered such that the predicted path
440 * sees a more linear flow, thus improving cache behavior, etc.
442 * The following two macros provide us with a way to utilize this
443 * compiler feature. Use __predict_true() if you expect the expression
444 * to evaluate to true, and __predict_false() if you expect the
445 * expression to evaluate to false.
447 * A few notes about usage:
449 * * Generally, __predict_false() error condition checks (unless
450 * you have some _strong_ reason to do otherwise, in which case
451 * document it), and/or __predict_true() `no-error' condition
452 * checks, assuming you want to optimize for the no-error case.
454 * * Other than that, if you don't know the likelihood of a test
455 * succeeding from empirical or other `hard' evidence, don't
458 * * These are meant to be used in places that are run `a lot'.
459 * It is wasteful to make predictions in code that is run
460 * seldomly (e.g. at subsystem initialization time) as the
461 * basic block reordering that this affects can often generate
464 #if __GNUC_PREREQ__(2, 96)
465 #define __predict_true(exp) __builtin_expect((exp), 1)
466 #define __predict_false(exp) __builtin_expect((exp), 0)
468 #define __predict_true(exp) (exp)
469 #define __predict_false(exp) (exp)
472 #if __GNUC_PREREQ__(4, 0)
473 #define __null_sentinel __attribute__((__sentinel__))
474 #define __exported __attribute__((__visibility__("default")))
475 #define __hidden __attribute__((__visibility__("hidden")))
477 #define __null_sentinel
483 * We define this here since <stddef.h>, <sys/queue.h>, and <sys/types.h>
486 #if __GNUC_PREREQ__(4, 1)
487 #define __offsetof(type, field) __builtin_offsetof(type, field)
490 #define __offsetof(type, field) \
491 ((__size_t)(__uintptr_t)((const volatile void *)&((type *)0)->field))
493 #define __offsetof(type, field) \
494 (__offsetof__ (reinterpret_cast <__size_t> \
495 (&reinterpret_cast <const volatile char &> \
496 (static_cast<type *> (0)->field))))
499 #define __rangeof(type, start, end) \
500 (__offsetof(type, end) - __offsetof(type, start))
503 * Given the pointer x to the member m of the struct s, return
504 * a pointer to the containing structure. When using GCC, we first
505 * assign pointer x to a local variable, to check that its type is
506 * compatible with member m.
508 #if __GNUC_PREREQ__(3, 1)
509 #define __containerof(x, s, m) ({ \
510 const volatile __typeof(((s *)0)->m) *__x = (x); \
511 __DEQUALIFY(s *, (const volatile char *)__x - __offsetof(s, m));\
514 #define __containerof(x, s, m) \
515 __DEQUALIFY(s *, (const volatile char *)(x) - __offsetof(s, m))
519 * Compiler-dependent macros to declare that functions take printf-like
520 * or scanf-like arguments. They are null except for versions of gcc
521 * that are known to support the features properly (old versions of gcc-2
522 * didn't permit keeping the keywords out of the application namespace).
524 #if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER)
525 #define __printflike(fmtarg, firstvararg)
526 #define __scanflike(fmtarg, firstvararg)
527 #define __format_arg(fmtarg)
528 #define __strfmonlike(fmtarg, firstvararg)
529 #define __strftimelike(fmtarg, firstvararg)
531 #define __printflike(fmtarg, firstvararg) \
532 __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
533 #define __scanflike(fmtarg, firstvararg) \
534 __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
535 #define __format_arg(fmtarg) __attribute__((__format_arg__ (fmtarg)))
536 #define __strfmonlike(fmtarg, firstvararg) \
537 __attribute__((__format__ (__strfmon__, fmtarg, firstvararg)))
538 #define __strftimelike(fmtarg, firstvararg) \
539 __attribute__((__format__ (__strftime__, fmtarg, firstvararg)))
542 /* Compiler-dependent macros that rely on FreeBSD-specific extensions. */
543 #if defined(__FreeBSD_cc_version) && __FreeBSD_cc_version >= 300001 && \
544 defined(__GNUC__) && !defined(__INTEL_COMPILER)
545 #define __printf0like(fmtarg, firstvararg) \
546 __attribute__((__format__ (__printf0__, fmtarg, firstvararg)))
548 #define __printf0like(fmtarg, firstvararg)
551 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
552 #ifndef __INTEL_COMPILER
553 #define __strong_reference(sym,aliassym) \
554 extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym)))
557 #define __weak_reference(sym,alias) \
558 __asm__(".weak " #alias); \
559 __asm__(".equ " #alias ", " #sym)
560 #define __warn_references(sym,msg) \
561 __asm__(".section .gnu.warning." #sym); \
562 __asm__(".asciz \"" msg "\""); \
564 #define __sym_compat(sym,impl,verid) \
565 __asm__(".symver " #impl ", " #sym "@" #verid)
566 #define __sym_default(sym,impl,verid) \
567 __asm__(".symver " #impl ", " #sym "@@" #verid)
569 #define __weak_reference(sym,alias) \
570 __asm__(".weak alias"); \
571 __asm__(".equ alias, sym")
572 #define __warn_references(sym,msg) \
573 __asm__(".section .gnu.warning.sym"); \
574 __asm__(".asciz \"msg\""); \
576 #define __sym_compat(sym,impl,verid) \
577 __asm__(".symver impl, sym@verid")
578 #define __sym_default(impl,sym,verid) \
579 __asm__(".symver impl, sym@@verid")
580 #endif /* __STDC__ */
581 #endif /* __GNUC__ || __INTEL_COMPILER */
583 #define __GLOBL1(sym) __asm__(".globl " #sym)
584 #define __GLOBL(sym) __GLOBL1(sym)
586 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
587 #define __IDSTRING(name,string) __asm__(".ident\t\"" string "\"")
590 * The following definition might not work well if used in header files,
591 * but it should be better than nothing. If you want a "do nothing"
592 * version, then it should generate some harmless declaration, such as:
593 * #define __IDSTRING(name,string) struct __hack
595 #define __IDSTRING(name,string) static const char name[] __unused = string
599 * Embed the rcs id of a source file in the resulting library. Note that in
600 * more recent ELF binutils, we use .ident allowing the ID to be stripped.
602 * __FBSDID("$FreeBSD$");
605 #if !defined(lint) && !defined(STRIP_FBSDID)
606 #define __FBSDID(s) __IDSTRING(__CONCAT(__rcsid_,__LINE__),s)
608 #define __FBSDID(s) struct __hack
614 #define __RCSID(s) __IDSTRING(__CONCAT(__rcsid_,__LINE__),s)
616 #define __RCSID(s) struct __hack
620 #ifndef __RCSID_SOURCE
621 #ifndef NO__RCSID_SOURCE
622 #define __RCSID_SOURCE(s) __IDSTRING(__CONCAT(__rcsid_source_,__LINE__),s)
624 #define __RCSID_SOURCE(s) struct __hack
630 #define __SCCSID(s) __IDSTRING(__CONCAT(__sccsid_,__LINE__),s)
632 #define __SCCSID(s) struct __hack
637 #ifndef NO__COPYRIGHT
638 #define __COPYRIGHT(s) __IDSTRING(__CONCAT(__copyright_,__LINE__),s)
640 #define __COPYRIGHT(s) struct __hack
645 #define __DECONST(type, var) ((type)(__uintptr_t)(const void *)(var))
649 #define __DEVOLATILE(type, var) ((type)(__uintptr_t)(volatile void *)(var))
653 #define __DEQUALIFY(type, var) ((type)(__uintptr_t)(const volatile void *)(var))
657 * The following definitions are an extension of the behavior originally
658 * implemented in <sys/_posix.h>, but with a different level of granularity.
659 * POSIX.1 requires that the macros we test be defined before any standard
660 * header file is included.
662 * Here's a quick run-down of the versions:
663 * defined(_POSIX_SOURCE) 1003.1-1988
664 * _POSIX_C_SOURCE == 1 1003.1-1990
665 * _POSIX_C_SOURCE == 2 1003.2-1992 C Language Binding Option
666 * _POSIX_C_SOURCE == 199309 1003.1b-1993
667 * _POSIX_C_SOURCE == 199506 1003.1c-1995, 1003.1i-1995,
668 * and the omnibus ISO/IEC 9945-1: 1996
669 * _POSIX_C_SOURCE == 200112 1003.1-2001
670 * _POSIX_C_SOURCE == 200809 1003.1-2008
672 * In addition, the X/Open Portability Guide, which is now the Single UNIX
673 * Specification, defines a feature-test macro which indicates the version of
674 * that specification, and which subsumes _POSIX_C_SOURCE.
676 * Our macros begin with two underscores to avoid namespace screwage.
679 /* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */
680 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 1
681 #undef _POSIX_C_SOURCE /* Probably illegal, but beyond caring now. */
682 #define _POSIX_C_SOURCE 199009
685 /* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */
686 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 2
687 #undef _POSIX_C_SOURCE
688 #define _POSIX_C_SOURCE 199209
691 /* Deal with various X/Open Portability Guides and Single UNIX Spec. */
693 #if _XOPEN_SOURCE - 0 >= 700
694 #define __XSI_VISIBLE 700
695 #undef _POSIX_C_SOURCE
696 #define _POSIX_C_SOURCE 200809
697 #elif _XOPEN_SOURCE - 0 >= 600
698 #define __XSI_VISIBLE 600
699 #undef _POSIX_C_SOURCE
700 #define _POSIX_C_SOURCE 200112
701 #elif _XOPEN_SOURCE - 0 >= 500
702 #define __XSI_VISIBLE 500
703 #undef _POSIX_C_SOURCE
704 #define _POSIX_C_SOURCE 199506
709 * Deal with all versions of POSIX. The ordering relative to the tests above is
712 #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
713 #define _POSIX_C_SOURCE 198808
715 #ifdef _POSIX_C_SOURCE
716 #if _POSIX_C_SOURCE >= 200809
717 #define __POSIX_VISIBLE 200809
718 #define __ISO_C_VISIBLE 1999
719 #elif _POSIX_C_SOURCE >= 200112
720 #define __POSIX_VISIBLE 200112
721 #define __ISO_C_VISIBLE 1999
722 #elif _POSIX_C_SOURCE >= 199506
723 #define __POSIX_VISIBLE 199506
724 #define __ISO_C_VISIBLE 1990
725 #elif _POSIX_C_SOURCE >= 199309
726 #define __POSIX_VISIBLE 199309
727 #define __ISO_C_VISIBLE 1990
728 #elif _POSIX_C_SOURCE >= 199209
729 #define __POSIX_VISIBLE 199209
730 #define __ISO_C_VISIBLE 1990
731 #elif _POSIX_C_SOURCE >= 199009
732 #define __POSIX_VISIBLE 199009
733 #define __ISO_C_VISIBLE 1990
735 #define __POSIX_VISIBLE 198808
736 #define __ISO_C_VISIBLE 0
737 #endif /* _POSIX_C_SOURCE */
740 * Deal with _ANSI_SOURCE:
741 * If it is defined, and no other compilation environment is explicitly
742 * requested, then define our internal feature-test macros to zero. This
743 * makes no difference to the preprocessor (undefined symbols in preprocessing
744 * expressions are defined to have value zero), but makes it more convenient for
745 * a test program to print out the values.
747 * If a program mistakenly defines _ANSI_SOURCE and some other macro such as
748 * _POSIX_C_SOURCE, we will assume that it wants the broader compilation
749 * environment (and in fact we will never get here).
751 #if defined(_ANSI_SOURCE) /* Hide almost everything. */
752 #define __POSIX_VISIBLE 0
753 #define __XSI_VISIBLE 0
754 #define __BSD_VISIBLE 0
755 #define __ISO_C_VISIBLE 1990
756 #define __EXT1_VISIBLE 0
757 #elif defined(_C99_SOURCE) /* Localism to specify strict C99 env. */
758 #define __POSIX_VISIBLE 0
759 #define __XSI_VISIBLE 0
760 #define __BSD_VISIBLE 0
761 #define __ISO_C_VISIBLE 1999
762 #define __EXT1_VISIBLE 0
763 #elif defined(_C11_SOURCE) /* Localism to specify strict C11 env. */
764 #define __POSIX_VISIBLE 0
765 #define __XSI_VISIBLE 0
766 #define __BSD_VISIBLE 0
767 #define __ISO_C_VISIBLE 2011
768 #define __EXT1_VISIBLE 0
769 #else /* Default environment: show everything. */
770 #define __POSIX_VISIBLE 200809
771 #define __XSI_VISIBLE 700
772 #define __BSD_VISIBLE 1
773 #define __ISO_C_VISIBLE 2011
774 #define __EXT1_VISIBLE 1
778 /* User override __EXT1_VISIBLE */
779 #if defined(__STDC_WANT_LIB_EXT1__)
780 #undef __EXT1_VISIBLE
781 #if __STDC_WANT_LIB_EXT1__
782 #define __EXT1_VISIBLE 1
784 #define __EXT1_VISIBLE 0
786 #endif /* __STDC_WANT_LIB_EXT1__ */
788 #if defined(__mips) || defined(__powerpc64__) || defined(__riscv__)
793 * Old versions of GCC use non-standard ARM arch symbols; acle-compat.h
794 * translates them to __ARM_ARCH and the modern feature symbols defined by ARM.
796 #if defined(__arm__) && !defined(__ARM_ARCH)
797 #include <machine/acle-compat.h>
801 * Nullability qualifiers: currently only supported by Clang.
803 #if !(defined(__clang__) && __has_feature(nullability))
806 #define _Null_unspecified
807 #define __NULLABILITY_PRAGMA_PUSH
808 #define __NULLABILITY_PRAGMA_POP
810 #define __NULLABILITY_PRAGMA_PUSH _Pragma("clang diagnostic push") \
811 _Pragma("clang diagnostic ignored \"-Wnullability-completeness\"")
812 #define __NULLABILITY_PRAGMA_POP _Pragma("clang diagnostic pop")
816 * Type Safety Checking
818 * Clang provides additional attributes to enable checking type safety
819 * properties that cannot be enforced by the C type system.
822 #if __has_attribute(__argument_with_type_tag__) && \
823 __has_attribute(__type_tag_for_datatype__) && !defined(lint)
824 #define __arg_type_tag(arg_kind, arg_idx, type_tag_idx) \
825 __attribute__((__argument_with_type_tag__(arg_kind, arg_idx, type_tag_idx)))
826 #define __datatype_type_tag(kind, type) \
827 __attribute__((__type_tag_for_datatype__(kind, type)))
829 #define __arg_type_tag(arg_kind, arg_idx, type_tag_idx)
830 #define __datatype_type_tag(kind, type)
836 * Clang provides support for doing basic thread-safety tests at
837 * compile-time, by marking which locks will/should be held when
838 * entering/leaving a functions.
840 * Furthermore, it is also possible to annotate variables and structure
841 * members to enforce that they are only accessed when certain locks are
845 #if __has_extension(c_thread_safety_attributes)
846 #define __lock_annotate(x) __attribute__((x))
848 #define __lock_annotate(x)
851 /* Structure implements a lock. */
852 #define __lockable __lock_annotate(lockable)
854 /* Function acquires an exclusive or shared lock. */
855 #define __locks_exclusive(...) \
856 __lock_annotate(exclusive_lock_function(__VA_ARGS__))
857 #define __locks_shared(...) \
858 __lock_annotate(shared_lock_function(__VA_ARGS__))
860 /* Function attempts to acquire an exclusive or shared lock. */
861 #define __trylocks_exclusive(...) \
862 __lock_annotate(exclusive_trylock_function(__VA_ARGS__))
863 #define __trylocks_shared(...) \
864 __lock_annotate(shared_trylock_function(__VA_ARGS__))
866 /* Function releases a lock. */
867 #define __unlocks(...) __lock_annotate(unlock_function(__VA_ARGS__))
869 /* Function asserts that an exclusive or shared lock is held. */
870 #define __asserts_exclusive(...) \
871 __lock_annotate(assert_exclusive_lock(__VA_ARGS__))
872 #define __asserts_shared(...) \
873 __lock_annotate(assert_shared_lock(__VA_ARGS__))
875 /* Function requires that an exclusive or shared lock is or is not held. */
876 #define __requires_exclusive(...) \
877 __lock_annotate(exclusive_locks_required(__VA_ARGS__))
878 #define __requires_shared(...) \
879 __lock_annotate(shared_locks_required(__VA_ARGS__))
880 #define __requires_unlocked(...) \
881 __lock_annotate(locks_excluded(__VA_ARGS__))
883 /* Function should not be analyzed. */
884 #define __no_lock_analysis __lock_annotate(no_thread_safety_analysis)
886 /* Guard variables and structure members by lock. */
887 #define __guarded_by(x) __lock_annotate(guarded_by(x))
888 #define __pt_guarded_by(x) __lock_annotate(pt_guarded_by(x))
890 #endif /* !_SYS_CDEFS_H_ */