2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1991, 1993
5 * The Regents of the University of California. All rights reserved.
7 * This code is derived from software contributed to Berkeley by
8 * Berkeley Software Design, Inc.
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * @(#)cdefs.h 8.8 (Berkeley) 1/9/95
41 #if defined(_KERNEL) && defined(_STANDALONE)
42 #error "_KERNEL and _STANDALONE are mutually exclusive"
46 * Testing against Clang-specific extensions.
48 #ifndef __has_attribute
49 #define __has_attribute(x) 0
51 #ifndef __has_extension
52 #define __has_extension __has_feature
55 #define __has_feature(x) 0
58 #define __has_include(x) 0
61 #define __has_builtin(x) 0
64 #if defined(__cplusplus)
65 #define __BEGIN_DECLS extern "C" {
73 * This code has been put in place to help reduce the addition of
74 * compiler specific defines in FreeBSD code. It helps to aid in
75 * having a compiler-agnostic source tree.
81 #define __GNUCLIKE_ASM 3
82 #define __GNUCLIKE_MATH_BUILTIN_CONSTANTS
84 #define __GNUCLIKE_ASM 2
86 #define __GNUCLIKE___TYPEOF 1
87 #define __GNUCLIKE___OFFSETOF 1
88 #define __GNUCLIKE___SECTION 1
90 #define __GNUCLIKE_CTOR_SECTION_HANDLING 1
92 #define __GNUCLIKE_BUILTIN_CONSTANT_P 1
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 #define __GNUCLIKE_BUILTIN_NEXT_ARG 1
112 #define __GNUCLIKE_MATH_BUILTIN_RELOPS
114 #define __GNUCLIKE_BUILTIN_MEMCPY 1
116 /* XXX: if __GNUC__ >= 2: not tested everywhere originally, where replaced */
117 #define __CC_SUPPORTS_INLINE 1
118 #define __CC_SUPPORTS___INLINE 1
119 #define __CC_SUPPORTS___INLINE__ 1
121 #define __CC_SUPPORTS___FUNC__ 1
122 #define __CC_SUPPORTS_WARNING 1
124 #define __CC_SUPPORTS_VARADIC_XXX 1 /* see varargs.h */
126 #define __CC_SUPPORTS_DYNAMIC_ARRAY_INIT 1
128 #endif /* __GNUC__ */
131 * Macro to test if we're using a specific version of gcc or later.
133 #if defined(__GNUC__)
134 #define __GNUC_PREREQ__(ma, mi) \
135 (__GNUC__ > (ma) || __GNUC__ == (ma) && __GNUC_MINOR__ >= (mi))
137 #define __GNUC_PREREQ__(ma, mi) 0
141 * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
142 * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
143 * The __CONCAT macro is a bit tricky to use if it must work in non-ANSI
144 * mode -- there must be no spaces between its arguments, and for nested
145 * __CONCAT's, all the __CONCAT's must be at the left. __CONCAT can also
146 * concatenate double-quoted strings produced by the __STRING macro, but
147 * this only works with ANSI C.
149 * __XSTRING is like __STRING, but it expands any macros in its argument
150 * first. It is only available with ANSI C.
152 #if defined(__STDC__) || defined(__cplusplus)
153 #define __P(protos) protos /* full-blown ANSI C */
154 #define __CONCAT1(x,y) x ## y
155 #define __CONCAT(x,y) __CONCAT1(x,y)
156 #define __STRING(x) #x /* stringify without expanding x */
157 #define __XSTRING(x) __STRING(x) /* expand x, then stringify */
159 #define __const const /* define reserved names to standard */
160 #define __signed signed
161 #define __volatile volatile
162 #if defined(__cplusplus)
163 #define __inline inline /* convert to C++ keyword */
165 #if !(defined(__CC_SUPPORTS___INLINE))
166 #define __inline /* delete GCC keyword */
167 #endif /* ! __CC_SUPPORTS___INLINE */
168 #endif /* !__cplusplus */
170 #else /* !(__STDC__ || __cplusplus) */
171 #define __P(protos) () /* traditional C preprocessor */
172 #define __CONCAT(x,y) x/**/y
173 #define __STRING(x) "x"
175 #if !defined(__CC_SUPPORTS___INLINE)
176 #define __const /* delete pseudo-ANSI C keywords */
181 * In non-ANSI C environments, new programs will want ANSI-only C keywords
182 * deleted from the program and old programs will want them left alone.
183 * When using a compiler other than gcc, programs using the ANSI C keywords
184 * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS.
185 * When using "gcc -traditional", we assume that this is the intent; if
186 * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone.
188 #ifndef NO_ANSI_KEYWORDS
189 #define const /* delete ANSI C keywords */
193 #endif /* !NO_ANSI_KEYWORDS */
194 #endif /* !__CC_SUPPORTS___INLINE */
195 #endif /* !(__STDC__ || __cplusplus) */
198 * Compiler-dependent macros to help declare dead (non-returning) and
199 * pure (no side effects) functions, and unused variables. They are
200 * null except for versions of gcc that are known to support the features
201 * properly (old versions of gcc-2 supported the dead and pure features
202 * in a different (wrong) way). If we do not provide an implementation
203 * for a given compiler, let the compile fail if it is told to use
204 * a feature that we cannot live without.
206 #define __weak_symbol __attribute__((__weak__))
207 #if !__GNUC_PREREQ__(2, 5)
212 #if __GNUC__ == 2 && __GNUC_MINOR__ >= 5 && __GNUC_MINOR__ < 7
213 #define __dead2 __attribute__((__noreturn__))
214 #define __pure2 __attribute__((__const__))
216 /* XXX Find out what to do for __packed, __aligned and __section */
218 #if __GNUC_PREREQ__(2, 7)
219 #define __dead2 __attribute__((__noreturn__))
220 #define __pure2 __attribute__((__const__))
221 #define __unused __attribute__((__unused__))
222 #define __used __attribute__((__used__))
223 #define __packed __attribute__((__packed__))
224 #define __aligned(x) __attribute__((__aligned__(x)))
225 #define __section(x) __attribute__((__section__(x)))
227 #if __GNUC_PREREQ__(4, 3) || __has_attribute(__alloc_size__)
228 #define __alloc_size(x) __attribute__((__alloc_size__(x)))
229 #define __alloc_size2(n, x) __attribute__((__alloc_size__(n, x)))
231 #define __alloc_size(x)
232 #define __alloc_size2(n, x)
234 #if __GNUC_PREREQ__(4, 9) || __has_attribute(__alloc_align__)
235 #define __alloc_align(x) __attribute__((__alloc_align__(x)))
237 #define __alloc_align(x)
240 #if !__GNUC_PREREQ__(2, 95)
241 #define __alignof(x) __offsetof(struct { char __a; x __b; }, __b)
245 * Keywords added in C11.
248 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L
250 #if !__has_extension(c_alignas)
251 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
252 __has_extension(cxx_alignas)
253 #define _Alignas(x) alignas(x)
255 /* XXX: Only emulates _Alignas(constant-expression); not _Alignas(type-name). */
256 #define _Alignas(x) __aligned(x)
260 #if defined(__cplusplus) && __cplusplus >= 201103L
261 #define _Alignof(x) alignof(x)
263 #define _Alignof(x) __alignof(x)
266 #if !defined(__cplusplus) && !__has_extension(c_atomic) && \
267 !__has_extension(cxx_atomic) && !__GNUC_PREREQ__(4, 7)
269 * No native support for _Atomic(). Place object in structure to prevent
270 * most forms of direct non-atomic access.
272 #define _Atomic(T) struct { T volatile __val; }
275 #if defined(__cplusplus) && __cplusplus >= 201103L
276 #define _Noreturn [[noreturn]]
278 #define _Noreturn __dead2
281 #if !__has_extension(c_static_assert)
282 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
283 __has_extension(cxx_static_assert)
284 #define _Static_assert(x, y) static_assert(x, y)
285 #elif __GNUC_PREREQ__(4,6) && !defined(__cplusplus)
286 /* Nothing, gcc 4.6 and higher has _Static_assert built-in */
287 #elif defined(__COUNTER__)
288 #define _Static_assert(x, y) __Static_assert(x, __COUNTER__)
289 #define __Static_assert(x, y) ___Static_assert(x, y)
290 #define ___Static_assert(x, y) typedef char __assert_ ## y[(x) ? 1 : -1] \
293 #define _Static_assert(x, y) struct __hack
297 #if !__has_extension(c_thread_local)
299 * XXX: Some compilers (Clang 3.3, GCC 4.7) falsely announce C++11 mode
300 * without actually supporting the thread_local keyword. Don't check for
301 * the presence of C++11 when defining _Thread_local.
303 #if /* (defined(__cplusplus) && __cplusplus >= 201103L) || */ \
304 __has_extension(cxx_thread_local)
305 #define _Thread_local thread_local
307 #define _Thread_local __thread
311 #endif /* __STDC_VERSION__ || __STDC_VERSION__ < 201112L */
314 * Emulation of C11 _Generic(). Unlike the previously defined C11
315 * keywords, it is not possible to implement this using exactly the same
316 * syntax. Therefore implement something similar under the name
317 * __generic(). Unlike _Generic(), this macro can only distinguish
318 * between a single type, so it requires nested invocations to
319 * distinguish multiple cases.
322 #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) || \
323 __has_extension(c_generic_selections)
324 #define __generic(expr, t, yes, no) \
325 _Generic(expr, t: yes, default: no)
326 #elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus)
327 #define __generic(expr, t, yes, no) \
328 __builtin_choose_expr( \
329 __builtin_types_compatible_p(__typeof(expr), t), yes, no)
333 * C99 Static array indices in function parameter declarations. Syntax such as:
334 * void bar(int myArray[static 10]);
335 * is allowed in C99 but not in C++. Define __min_size appropriately so
336 * headers using it can be compiled in either language. Use like this:
337 * void bar(int myArray[__min_size(10)]);
339 #if !defined(__cplusplus) && \
340 (defined(__clang__) || __GNUC_PREREQ__(4, 6)) && \
341 (!defined(__STDC_VERSION__) || (__STDC_VERSION__ >= 199901))
342 #define __min_size(x) static (x)
344 #define __min_size(x) (x)
347 #if __GNUC_PREREQ__(2, 96)
348 #define __malloc_like __attribute__((__malloc__))
349 #define __pure __attribute__((__pure__))
351 #define __malloc_like
355 #if __GNUC_PREREQ__(3, 1)
356 #define __always_inline __attribute__((__always_inline__))
358 #define __always_inline
361 #if __GNUC_PREREQ__(3, 1)
362 #define __noinline __attribute__ ((__noinline__))
367 #if __GNUC_PREREQ__(3, 4)
368 #define __fastcall __attribute__((__fastcall__))
369 #define __result_use_check __attribute__((__warn_unused_result__))
372 #define __result_use_check
375 #if __GNUC_PREREQ__(4, 1)
376 #define __returns_twice __attribute__((__returns_twice__))
378 #define __returns_twice
381 #if __GNUC_PREREQ__(4, 6) || __has_builtin(__builtin_unreachable)
382 #define __unreachable() __builtin_unreachable()
384 #define __unreachable() ((void)0)
387 /* XXX: should use `#if __STDC_VERSION__ < 199901'. */
388 #if !__GNUC_PREREQ__(2, 7)
389 #define __func__ NULL
392 #if (defined(__GNUC__) && __GNUC__ >= 2) && !defined(__STRICT_ANSI__) || __STDC_VERSION__ >= 199901
393 #define __LONG_LONG_SUPPORTED
396 /* C++11 exposes a load of C99 stuff */
397 #if defined(__cplusplus) && __cplusplus >= 201103L
398 #define __LONG_LONG_SUPPORTED
399 #ifndef __STDC_LIMIT_MACROS
400 #define __STDC_LIMIT_MACROS
402 #ifndef __STDC_CONSTANT_MACROS
403 #define __STDC_CONSTANT_MACROS
408 * GCC 2.95 provides `__restrict' as an extension to C90 to support the
409 * C99-specific `restrict' type qualifier. We happen to use `__restrict' as
410 * a way to define the `restrict' type qualifier without disturbing older
411 * software that is unaware of C99 keywords.
413 #if !(__GNUC__ == 2 && __GNUC_MINOR__ == 95)
414 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 199901
417 #define __restrict restrict
422 * GNU C version 2.96 adds explicit branch prediction so that
423 * the CPU back-end can hint the processor and also so that
424 * code blocks can be reordered such that the predicted path
425 * sees a more linear flow, thus improving cache behavior, etc.
427 * The following two macros provide us with a way to utilize this
428 * compiler feature. Use __predict_true() if you expect the expression
429 * to evaluate to true, and __predict_false() if you expect the
430 * expression to evaluate to false.
432 * A few notes about usage:
434 * * Generally, __predict_false() error condition checks (unless
435 * you have some _strong_ reason to do otherwise, in which case
436 * document it), and/or __predict_true() `no-error' condition
437 * checks, assuming you want to optimize for the no-error case.
439 * * Other than that, if you don't know the likelihood of a test
440 * succeeding from empirical or other `hard' evidence, don't
443 * * These are meant to be used in places that are run `a lot'.
444 * It is wasteful to make predictions in code that is run
445 * seldomly (e.g. at subsystem initialization time) as the
446 * basic block reordering that this affects can often generate
449 #if __GNUC_PREREQ__(2, 96)
450 #define __predict_true(exp) __builtin_expect((exp), 1)
451 #define __predict_false(exp) __builtin_expect((exp), 0)
453 #define __predict_true(exp) (exp)
454 #define __predict_false(exp) (exp)
457 #if __GNUC_PREREQ__(4, 0)
458 #define __null_sentinel __attribute__((__sentinel__))
459 #define __exported __attribute__((__visibility__("default")))
460 #define __hidden __attribute__((__visibility__("hidden")))
462 #define __null_sentinel
468 * We define this here since <stddef.h>, <sys/queue.h>, and <sys/types.h>
471 #if __GNUC_PREREQ__(4, 1)
472 #define __offsetof(type, field) __builtin_offsetof(type, field)
475 #define __offsetof(type, field) \
476 ((__size_t)(__uintptr_t)((const volatile void *)&((type *)0)->field))
478 #define __offsetof(type, field) \
479 (__offsetof__ (reinterpret_cast <__size_t> \
480 (&reinterpret_cast <const volatile char &> \
481 (static_cast<type *> (0)->field))))
484 #define __rangeof(type, start, end) \
485 (__offsetof(type, end) - __offsetof(type, start))
488 * Given the pointer x to the member m of the struct s, return
489 * a pointer to the containing structure. When using GCC, we first
490 * assign pointer x to a local variable, to check that its type is
491 * compatible with member m.
493 #if __GNUC_PREREQ__(3, 1)
494 #define __containerof(x, s, m) ({ \
495 const volatile __typeof(((s *)0)->m) *__x = (x); \
496 __DEQUALIFY(s *, (const volatile char *)__x - __offsetof(s, m));\
499 #define __containerof(x, s, m) \
500 __DEQUALIFY(s *, (const volatile char *)(x) - __offsetof(s, m))
504 * Compiler-dependent macros to declare that functions take printf-like
505 * or scanf-like arguments. They are null except for versions of gcc
506 * that are known to support the features properly (old versions of gcc-2
507 * didn't permit keeping the keywords out of the application namespace).
509 #if !__GNUC_PREREQ__(2, 7)
510 #define __printflike(fmtarg, firstvararg)
511 #define __scanflike(fmtarg, firstvararg)
512 #define __format_arg(fmtarg)
513 #define __strfmonlike(fmtarg, firstvararg)
514 #define __strftimelike(fmtarg, firstvararg)
516 #define __printflike(fmtarg, firstvararg) \
517 __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
518 #define __scanflike(fmtarg, firstvararg) \
519 __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
520 #define __format_arg(fmtarg) __attribute__((__format_arg__ (fmtarg)))
521 #define __strfmonlike(fmtarg, firstvararg) \
522 __attribute__((__format__ (__strfmon__, fmtarg, firstvararg)))
523 #define __strftimelike(fmtarg, firstvararg) \
524 __attribute__((__format__ (__strftime__, fmtarg, firstvararg)))
527 /* Compiler-dependent macros that rely on FreeBSD-specific extensions. */
528 #if defined(__FreeBSD_cc_version) && __FreeBSD_cc_version >= 300001 && \
530 #define __printf0like(fmtarg, firstvararg) \
531 __attribute__((__format__ (__printf0__, fmtarg, firstvararg)))
533 #define __printf0like(fmtarg, firstvararg)
536 #if defined(__GNUC__)
537 #define __strong_reference(sym,aliassym) \
538 extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym)))
540 #define __weak_reference(sym,alias) \
541 __asm__(".weak " #alias); \
542 __asm__(".equ " #alias ", " #sym)
543 #define __warn_references(sym,msg) \
544 __asm__(".section .gnu.warning." #sym); \
545 __asm__(".asciz \"" msg "\""); \
547 #define __sym_compat(sym,impl,verid) \
548 __asm__(".symver " #impl ", " #sym "@" #verid)
549 #define __sym_default(sym,impl,verid) \
550 __asm__(".symver " #impl ", " #sym "@@@" #verid)
552 #define __weak_reference(sym,alias) \
553 __asm__(".weak alias"); \
554 __asm__(".equ alias, sym")
555 #define __warn_references(sym,msg) \
556 __asm__(".section .gnu.warning.sym"); \
557 __asm__(".asciz \"msg\""); \
559 #define __sym_compat(sym,impl,verid) \
560 __asm__(".symver impl, sym@verid")
561 #define __sym_default(impl,sym,verid) \
562 __asm__(".symver impl, sym@@@verid")
563 #endif /* __STDC__ */
564 #endif /* __GNUC__ */
566 #define __GLOBL(sym) __asm__(".globl " __XSTRING(sym))
567 #define __WEAK(sym) __asm__(".weak " __XSTRING(sym))
569 #if defined(__GNUC__)
570 #define __IDSTRING(name,string) __asm__(".ident\t\"" string "\"")
573 * The following definition might not work well if used in header files,
574 * but it should be better than nothing. If you want a "do nothing"
575 * version, then it should generate some harmless declaration, such as:
576 * #define __IDSTRING(name,string) struct __hack
578 #define __IDSTRING(name,string) static const char name[] __unused = string
582 * Embed the rcs id of a source file in the resulting library. Note that in
583 * more recent ELF binutils, we use .ident allowing the ID to be stripped.
585 * __FBSDID("$FreeBSD$");
588 #if !defined(STRIP_FBSDID)
589 #define __FBSDID(s) __IDSTRING(__CONCAT(__rcsid_,__LINE__),s)
591 #define __FBSDID(s) struct __hack
597 #define __RCSID(s) __IDSTRING(__CONCAT(__rcsid_,__LINE__),s)
599 #define __RCSID(s) struct __hack
603 #ifndef __RCSID_SOURCE
604 #ifndef NO__RCSID_SOURCE
605 #define __RCSID_SOURCE(s) __IDSTRING(__CONCAT(__rcsid_source_,__LINE__),s)
607 #define __RCSID_SOURCE(s) struct __hack
613 #define __SCCSID(s) __IDSTRING(__CONCAT(__sccsid_,__LINE__),s)
615 #define __SCCSID(s) struct __hack
620 #ifndef NO__COPYRIGHT
621 #define __COPYRIGHT(s) __IDSTRING(__CONCAT(__copyright_,__LINE__),s)
623 #define __COPYRIGHT(s) struct __hack
628 #define __DECONST(type, var) ((type)(__uintptr_t)(const void *)(var))
632 #define __DEVOLATILE(type, var) ((type)(__uintptr_t)(volatile void *)(var))
636 #define __DEQUALIFY(type, var) ((type)(__uintptr_t)(const volatile void *)(var))
640 * The following definitions are an extension of the behavior originally
641 * implemented in <sys/_posix.h>, but with a different level of granularity.
642 * POSIX.1 requires that the macros we test be defined before any standard
643 * header file is included.
645 * Here's a quick run-down of the versions:
646 * defined(_POSIX_SOURCE) 1003.1-1988
647 * _POSIX_C_SOURCE == 1 1003.1-1990
648 * _POSIX_C_SOURCE == 2 1003.2-1992 C Language Binding Option
649 * _POSIX_C_SOURCE == 199309 1003.1b-1993
650 * _POSIX_C_SOURCE == 199506 1003.1c-1995, 1003.1i-1995,
651 * and the omnibus ISO/IEC 9945-1: 1996
652 * _POSIX_C_SOURCE == 200112 1003.1-2001
653 * _POSIX_C_SOURCE == 200809 1003.1-2008
655 * In addition, the X/Open Portability Guide, which is now the Single UNIX
656 * Specification, defines a feature-test macro which indicates the version of
657 * that specification, and which subsumes _POSIX_C_SOURCE.
659 * Our macros begin with two underscores to avoid namespace screwage.
662 /* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */
663 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 1
664 #undef _POSIX_C_SOURCE /* Probably illegal, but beyond caring now. */
665 #define _POSIX_C_SOURCE 199009
668 /* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */
669 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 2
670 #undef _POSIX_C_SOURCE
671 #define _POSIX_C_SOURCE 199209
674 /* Deal with various X/Open Portability Guides and Single UNIX Spec. */
676 #if _XOPEN_SOURCE - 0 >= 700
677 #define __XSI_VISIBLE 700
678 #undef _POSIX_C_SOURCE
679 #define _POSIX_C_SOURCE 200809
680 #elif _XOPEN_SOURCE - 0 >= 600
681 #define __XSI_VISIBLE 600
682 #undef _POSIX_C_SOURCE
683 #define _POSIX_C_SOURCE 200112
684 #elif _XOPEN_SOURCE - 0 >= 500
685 #define __XSI_VISIBLE 500
686 #undef _POSIX_C_SOURCE
687 #define _POSIX_C_SOURCE 199506
692 * Deal with all versions of POSIX. The ordering relative to the tests above is
695 #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
696 #define _POSIX_C_SOURCE 198808
698 #ifdef _POSIX_C_SOURCE
699 #if _POSIX_C_SOURCE >= 200809
700 #define __POSIX_VISIBLE 200809
701 #define __ISO_C_VISIBLE 1999
702 #elif _POSIX_C_SOURCE >= 200112
703 #define __POSIX_VISIBLE 200112
704 #define __ISO_C_VISIBLE 1999
705 #elif _POSIX_C_SOURCE >= 199506
706 #define __POSIX_VISIBLE 199506
707 #define __ISO_C_VISIBLE 1990
708 #elif _POSIX_C_SOURCE >= 199309
709 #define __POSIX_VISIBLE 199309
710 #define __ISO_C_VISIBLE 1990
711 #elif _POSIX_C_SOURCE >= 199209
712 #define __POSIX_VISIBLE 199209
713 #define __ISO_C_VISIBLE 1990
714 #elif _POSIX_C_SOURCE >= 199009
715 #define __POSIX_VISIBLE 199009
716 #define __ISO_C_VISIBLE 1990
718 #define __POSIX_VISIBLE 198808
719 #define __ISO_C_VISIBLE 0
720 #endif /* _POSIX_C_SOURCE */
723 * Deal with _ANSI_SOURCE:
724 * If it is defined, and no other compilation environment is explicitly
725 * requested, then define our internal feature-test macros to zero. This
726 * makes no difference to the preprocessor (undefined symbols in preprocessing
727 * expressions are defined to have value zero), but makes it more convenient for
728 * a test program to print out the values.
730 * If a program mistakenly defines _ANSI_SOURCE and some other macro such as
731 * _POSIX_C_SOURCE, we will assume that it wants the broader compilation
732 * environment (and in fact we will never get here).
734 #if defined(_ANSI_SOURCE) /* Hide almost everything. */
735 #define __POSIX_VISIBLE 0
736 #define __XSI_VISIBLE 0
737 #define __BSD_VISIBLE 0
738 #define __ISO_C_VISIBLE 1990
739 #define __EXT1_VISIBLE 0
740 #elif defined(_C99_SOURCE) /* Localism to specify strict C99 env. */
741 #define __POSIX_VISIBLE 0
742 #define __XSI_VISIBLE 0
743 #define __BSD_VISIBLE 0
744 #define __ISO_C_VISIBLE 1999
745 #define __EXT1_VISIBLE 0
746 #elif defined(_C11_SOURCE) /* Localism to specify strict C11 env. */
747 #define __POSIX_VISIBLE 0
748 #define __XSI_VISIBLE 0
749 #define __BSD_VISIBLE 0
750 #define __ISO_C_VISIBLE 2011
751 #define __EXT1_VISIBLE 0
752 #else /* Default environment: show everything. */
753 #define __POSIX_VISIBLE 200809
754 #define __XSI_VISIBLE 700
755 #define __BSD_VISIBLE 1
756 #define __ISO_C_VISIBLE 2011
757 #define __EXT1_VISIBLE 1
761 /* User override __EXT1_VISIBLE */
762 #if defined(__STDC_WANT_LIB_EXT1__)
763 #undef __EXT1_VISIBLE
764 #if __STDC_WANT_LIB_EXT1__
765 #define __EXT1_VISIBLE 1
767 #define __EXT1_VISIBLE 0
769 #endif /* __STDC_WANT_LIB_EXT1__ */
772 * Old versions of GCC use non-standard ARM arch symbols; acle-compat.h
773 * translates them to __ARM_ARCH and the modern feature symbols defined by ARM.
775 #if defined(__arm__) && !defined(__ARM_ARCH)
776 #include <machine/acle-compat.h>
780 * Nullability qualifiers: currently only supported by Clang.
782 #if !(defined(__clang__) && __has_feature(nullability))
785 #define _Null_unspecified
786 #define __NULLABILITY_PRAGMA_PUSH
787 #define __NULLABILITY_PRAGMA_POP
789 #define __NULLABILITY_PRAGMA_PUSH _Pragma("clang diagnostic push") \
790 _Pragma("clang diagnostic ignored \"-Wnullability-completeness\"")
791 #define __NULLABILITY_PRAGMA_POP _Pragma("clang diagnostic pop")
795 * Type Safety Checking
797 * Clang provides additional attributes to enable checking type safety
798 * properties that cannot be enforced by the C type system.
801 #if __has_attribute(__argument_with_type_tag__) && \
802 __has_attribute(__type_tag_for_datatype__)
803 #define __arg_type_tag(arg_kind, arg_idx, type_tag_idx) \
804 __attribute__((__argument_with_type_tag__(arg_kind, arg_idx, type_tag_idx)))
805 #define __datatype_type_tag(kind, type) \
806 __attribute__((__type_tag_for_datatype__(kind, type)))
808 #define __arg_type_tag(arg_kind, arg_idx, type_tag_idx)
809 #define __datatype_type_tag(kind, type)
815 * Clang provides support for doing basic thread-safety tests at
816 * compile-time, by marking which locks will/should be held when
817 * entering/leaving a functions.
819 * Furthermore, it is also possible to annotate variables and structure
820 * members to enforce that they are only accessed when certain locks are
824 #if __has_extension(c_thread_safety_attributes)
825 #define __lock_annotate(x) __attribute__((x))
827 #define __lock_annotate(x)
830 /* Structure implements a lock. */
831 #define __lockable __lock_annotate(lockable)
833 /* Function acquires an exclusive or shared lock. */
834 #define __locks_exclusive(...) \
835 __lock_annotate(exclusive_lock_function(__VA_ARGS__))
836 #define __locks_shared(...) \
837 __lock_annotate(shared_lock_function(__VA_ARGS__))
839 /* Function attempts to acquire an exclusive or shared lock. */
840 #define __trylocks_exclusive(...) \
841 __lock_annotate(exclusive_trylock_function(__VA_ARGS__))
842 #define __trylocks_shared(...) \
843 __lock_annotate(shared_trylock_function(__VA_ARGS__))
845 /* Function releases a lock. */
846 #define __unlocks(...) __lock_annotate(unlock_function(__VA_ARGS__))
848 /* Function asserts that an exclusive or shared lock is held. */
849 #define __asserts_exclusive(...) \
850 __lock_annotate(assert_exclusive_lock(__VA_ARGS__))
851 #define __asserts_shared(...) \
852 __lock_annotate(assert_shared_lock(__VA_ARGS__))
854 /* Function requires that an exclusive or shared lock is or is not held. */
855 #define __requires_exclusive(...) \
856 __lock_annotate(exclusive_locks_required(__VA_ARGS__))
857 #define __requires_shared(...) \
858 __lock_annotate(shared_locks_required(__VA_ARGS__))
859 #define __requires_unlocked(...) \
860 __lock_annotate(locks_excluded(__VA_ARGS__))
862 /* Function should not be analyzed. */
863 #define __no_lock_analysis __lock_annotate(no_thread_safety_analysis)
866 * Function or variable should not be sanitized, i.e. by AddressSanitizer.
867 * GCC has the nosanitize attribute, but as a function attribute only, and
868 * warns on use as a variable attribute.
870 #if __has_attribute(no_sanitize) && defined(__clang__)
871 #define __nosanitizeaddress __attribute__((no_sanitize("address")))
872 #define __nosanitizethread __attribute__((no_sanitize("thread")))
874 #define __nosanitizeaddress
875 #define __nosanitizememory
876 #define __nosanitizethread
879 /* Guard variables and structure members by lock. */
880 #define __guarded_by(x) __lock_annotate(guarded_by(x))
881 #define __pt_guarded_by(x) __lock_annotate(pt_guarded_by(x))
883 /* Alignment builtins for better type checking and improved code generation. */
884 /* Provide fallback versions for other compilers (GCC/Clang < 10): */
885 #if !__has_builtin(__builtin_is_aligned)
886 #define __builtin_is_aligned(x, align) \
887 (((__uintptr_t)x & ((align) - 1)) == 0)
889 #if !__has_builtin(__builtin_align_up)
890 #define __builtin_align_up(x, align) \
891 ((__typeof__(x))(((__uintptr_t)(x)+((align)-1))&(~((align)-1))))
893 #if !__has_builtin(__builtin_align_down)
894 #define __builtin_align_down(x, align) \
895 ((__typeof__(x))((x)&(~((align)-1))))
898 #define __align_up(x, y) __builtin_align_up(x, y)
899 #define __align_down(x, y) __builtin_align_down(x, y)
900 #define __is_aligned(x, y) __builtin_is_aligned(x, y)
902 #endif /* !_SYS_CDEFS_H_ */