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.
78 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
80 #if __GNUC__ >= 3 || defined(__INTEL_COMPILER)
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 #ifndef __INTEL_COMPILER
91 #define __GNUCLIKE_CTOR_SECTION_HANDLING 1
94 #define __GNUCLIKE_BUILTIN_CONSTANT_P 1
95 #if defined(__INTEL_COMPILER) && defined(__cplusplus) && \
96 __INTEL_COMPILER < 800
97 #undef __GNUCLIKE_BUILTIN_CONSTANT_P
100 #if (__GNUC_MINOR__ > 95 || __GNUC__ >= 3)
101 #define __GNUCLIKE_BUILTIN_VARARGS 1
102 #define __GNUCLIKE_BUILTIN_STDARG 1
103 #define __GNUCLIKE_BUILTIN_VAALIST 1
106 #if defined(__GNUC__)
107 #define __GNUC_VA_LIST_COMPATIBILITY 1
111 * Compiler memory barriers, specific to gcc and clang.
113 #if defined(__GNUC__)
114 #define __compiler_membar() __asm __volatile(" " : : : "memory")
117 #ifndef __INTEL_COMPILER
118 #define __GNUCLIKE_BUILTIN_NEXT_ARG 1
119 #define __GNUCLIKE_MATH_BUILTIN_RELOPS
122 #define __GNUCLIKE_BUILTIN_MEMCPY 1
124 /* XXX: if __GNUC__ >= 2: not tested everywhere originally, where replaced */
125 #define __CC_SUPPORTS_INLINE 1
126 #define __CC_SUPPORTS___INLINE 1
127 #define __CC_SUPPORTS___INLINE__ 1
129 #define __CC_SUPPORTS___FUNC__ 1
130 #define __CC_SUPPORTS_WARNING 1
132 #define __CC_SUPPORTS_VARADIC_XXX 1 /* see varargs.h */
134 #define __CC_SUPPORTS_DYNAMIC_ARRAY_INIT 1
136 #endif /* __GNUC__ || __INTEL_COMPILER */
139 * Macro to test if we're using a specific version of gcc or later.
141 #if defined(__GNUC__) && !defined(__INTEL_COMPILER)
142 #define __GNUC_PREREQ__(ma, mi) \
143 (__GNUC__ > (ma) || __GNUC__ == (ma) && __GNUC_MINOR__ >= (mi))
145 #define __GNUC_PREREQ__(ma, mi) 0
149 * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
150 * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
151 * The __CONCAT macro is a bit tricky to use if it must work in non-ANSI
152 * mode -- there must be no spaces between its arguments, and for nested
153 * __CONCAT's, all the __CONCAT's must be at the left. __CONCAT can also
154 * concatenate double-quoted strings produced by the __STRING macro, but
155 * this only works with ANSI C.
157 * __XSTRING is like __STRING, but it expands any macros in its argument
158 * first. It is only available with ANSI C.
160 #if defined(__STDC__) || defined(__cplusplus)
161 #define __P(protos) protos /* full-blown ANSI C */
162 #define __CONCAT1(x,y) x ## y
163 #define __CONCAT(x,y) __CONCAT1(x,y)
164 #define __STRING(x) #x /* stringify without expanding x */
165 #define __XSTRING(x) __STRING(x) /* expand x, then stringify */
167 #define __const const /* define reserved names to standard */
168 #define __signed signed
169 #define __volatile volatile
170 #if defined(__cplusplus)
171 #define __inline inline /* convert to C++ keyword */
173 #if !(defined(__CC_SUPPORTS___INLINE))
174 #define __inline /* delete GCC keyword */
175 #endif /* ! __CC_SUPPORTS___INLINE */
176 #endif /* !__cplusplus */
178 #else /* !(__STDC__ || __cplusplus) */
179 #define __P(protos) () /* traditional C preprocessor */
180 #define __CONCAT(x,y) x/**/y
181 #define __STRING(x) "x"
183 #if !defined(__CC_SUPPORTS___INLINE)
184 #define __const /* delete pseudo-ANSI C keywords */
189 * In non-ANSI C environments, new programs will want ANSI-only C keywords
190 * deleted from the program and old programs will want them left alone.
191 * When using a compiler other than gcc, programs using the ANSI C keywords
192 * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS.
193 * When using "gcc -traditional", we assume that this is the intent; if
194 * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone.
196 #ifndef NO_ANSI_KEYWORDS
197 #define const /* delete ANSI C keywords */
201 #endif /* !NO_ANSI_KEYWORDS */
202 #endif /* !__CC_SUPPORTS___INLINE */
203 #endif /* !(__STDC__ || __cplusplus) */
206 * Compiler-dependent macros to help declare dead (non-returning) and
207 * pure (no side effects) functions, and unused variables. They are
208 * null except for versions of gcc that are known to support the features
209 * properly (old versions of gcc-2 supported the dead and pure features
210 * in a different (wrong) way). If we do not provide an implementation
211 * for a given compiler, let the compile fail if it is told to use
212 * a feature that we cannot live without.
214 #define __weak_symbol __attribute__((__weak__))
215 #if !__GNUC_PREREQ__(2, 5) && !defined(__INTEL_COMPILER)
220 #if __GNUC__ == 2 && __GNUC_MINOR__ >= 5 && __GNUC_MINOR__ < 7 && !defined(__INTEL_COMPILER)
221 #define __dead2 __attribute__((__noreturn__))
222 #define __pure2 __attribute__((__const__))
224 /* XXX Find out what to do for __packed, __aligned and __section */
226 #if __GNUC_PREREQ__(2, 7) || defined(__INTEL_COMPILER)
227 #define __dead2 __attribute__((__noreturn__))
228 #define __pure2 __attribute__((__const__))
229 #define __unused __attribute__((__unused__))
230 #define __used __attribute__((__used__))
231 #define __packed __attribute__((__packed__))
232 #define __aligned(x) __attribute__((__aligned__(x)))
233 #define __section(x) __attribute__((__section__(x)))
235 #if __GNUC_PREREQ__(4, 3) || __has_attribute(__alloc_size__)
236 #define __alloc_size(x) __attribute__((__alloc_size__(x)))
237 #define __alloc_size2(n, x) __attribute__((__alloc_size__(n, x)))
239 #define __alloc_size(x)
240 #define __alloc_size2(n, x)
242 #if __GNUC_PREREQ__(4, 9) || __has_attribute(__alloc_align__)
243 #define __alloc_align(x) __attribute__((__alloc_align__(x)))
245 #define __alloc_align(x)
248 #if !__GNUC_PREREQ__(2, 95)
249 #define __alignof(x) __offsetof(struct { char __a; x __b; }, __b)
253 * Keywords added in C11.
256 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L
258 #if !__has_extension(c_alignas)
259 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
260 __has_extension(cxx_alignas)
261 #define _Alignas(x) alignas(x)
263 /* XXX: Only emulates _Alignas(constant-expression); not _Alignas(type-name). */
264 #define _Alignas(x) __aligned(x)
268 #if defined(__cplusplus) && __cplusplus >= 201103L
269 #define _Alignof(x) alignof(x)
271 #define _Alignof(x) __alignof(x)
274 #if !defined(__cplusplus) && !__has_extension(c_atomic) && \
275 !__has_extension(cxx_atomic) && !__GNUC_PREREQ__(4, 7)
277 * No native support for _Atomic(). Place object in structure to prevent
278 * most forms of direct non-atomic access.
280 #define _Atomic(T) struct { T volatile __val; }
283 #if defined(__cplusplus) && __cplusplus >= 201103L
284 #define _Noreturn [[noreturn]]
286 #define _Noreturn __dead2
289 #if !__has_extension(c_static_assert)
290 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
291 __has_extension(cxx_static_assert)
292 #define _Static_assert(x, y) static_assert(x, y)
293 #elif __GNUC_PREREQ__(4,6) && !defined(__cplusplus)
294 /* Nothing, gcc 4.6 and higher has _Static_assert built-in */
295 #elif defined(__COUNTER__)
296 #define _Static_assert(x, y) __Static_assert(x, __COUNTER__)
297 #define __Static_assert(x, y) ___Static_assert(x, y)
298 #define ___Static_assert(x, y) typedef char __assert_ ## y[(x) ? 1 : -1] \
301 #define _Static_assert(x, y) struct __hack
305 #if !__has_extension(c_thread_local)
307 * XXX: Some compilers (Clang 3.3, GCC 4.7) falsely announce C++11 mode
308 * without actually supporting the thread_local keyword. Don't check for
309 * the presence of C++11 when defining _Thread_local.
311 #if /* (defined(__cplusplus) && __cplusplus >= 201103L) || */ \
312 __has_extension(cxx_thread_local)
313 #define _Thread_local thread_local
315 #define _Thread_local __thread
319 #endif /* __STDC_VERSION__ || __STDC_VERSION__ < 201112L */
322 * Emulation of C11 _Generic(). Unlike the previously defined C11
323 * keywords, it is not possible to implement this using exactly the same
324 * syntax. Therefore implement something similar under the name
325 * __generic(). Unlike _Generic(), this macro can only distinguish
326 * between a single type, so it requires nested invocations to
327 * distinguish multiple cases.
330 #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) || \
331 __has_extension(c_generic_selections)
332 #define __generic(expr, t, yes, no) \
333 _Generic(expr, t: yes, default: no)
334 #elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus)
335 #define __generic(expr, t, yes, no) \
336 __builtin_choose_expr( \
337 __builtin_types_compatible_p(__typeof(expr), t), yes, no)
341 * C99 Static array indices in function parameter declarations. Syntax such as:
342 * void bar(int myArray[static 10]);
343 * is allowed in C99 but not in C++. Define __min_size appropriately so
344 * headers using it can be compiled in either language. Use like this:
345 * void bar(int myArray[__min_size(10)]);
347 #if !defined(__cplusplus) && \
348 (defined(__clang__) || __GNUC_PREREQ__(4, 6)) && \
349 (!defined(__STDC_VERSION__) || (__STDC_VERSION__ >= 199901))
350 #define __min_size(x) static (x)
352 #define __min_size(x) (x)
355 #if __GNUC_PREREQ__(2, 96)
356 #define __malloc_like __attribute__((__malloc__))
357 #define __pure __attribute__((__pure__))
359 #define __malloc_like
363 #if __GNUC_PREREQ__(3, 1) || (defined(__INTEL_COMPILER) && __INTEL_COMPILER >= 800)
364 #define __always_inline __attribute__((__always_inline__))
366 #define __always_inline
369 #if __GNUC_PREREQ__(3, 1)
370 #define __noinline __attribute__ ((__noinline__))
375 #if __GNUC_PREREQ__(3, 4)
376 #define __fastcall __attribute__((__fastcall__))
377 #define __result_use_check __attribute__((__warn_unused_result__))
380 #define __result_use_check
383 #if __GNUC_PREREQ__(4, 1)
384 #define __returns_twice __attribute__((__returns_twice__))
386 #define __returns_twice
389 #if __GNUC_PREREQ__(4, 6) || __has_builtin(__builtin_unreachable)
390 #define __unreachable() __builtin_unreachable()
392 #define __unreachable() ((void)0)
395 /* XXX: should use `#if __STDC_VERSION__ < 199901'. */
396 #if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER)
397 #define __func__ NULL
400 #if (defined(__INTEL_COMPILER) || (defined(__GNUC__) && __GNUC__ >= 2)) && !defined(__STRICT_ANSI__) || __STDC_VERSION__ >= 199901
401 #define __LONG_LONG_SUPPORTED
404 /* C++11 exposes a load of C99 stuff */
405 #if defined(__cplusplus) && __cplusplus >= 201103L
406 #define __LONG_LONG_SUPPORTED
407 #ifndef __STDC_LIMIT_MACROS
408 #define __STDC_LIMIT_MACROS
410 #ifndef __STDC_CONSTANT_MACROS
411 #define __STDC_CONSTANT_MACROS
416 * GCC 2.95 provides `__restrict' as an extension to C90 to support the
417 * C99-specific `restrict' type qualifier. We happen to use `__restrict' as
418 * a way to define the `restrict' type qualifier without disturbing older
419 * software that is unaware of C99 keywords.
421 #if !(__GNUC__ == 2 && __GNUC_MINOR__ == 95)
422 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 199901
425 #define __restrict restrict
430 * GNU C version 2.96 adds explicit branch prediction so that
431 * the CPU back-end can hint the processor and also so that
432 * code blocks can be reordered such that the predicted path
433 * sees a more linear flow, thus improving cache behavior, etc.
435 * The following two macros provide us with a way to utilize this
436 * compiler feature. Use __predict_true() if you expect the expression
437 * to evaluate to true, and __predict_false() if you expect the
438 * expression to evaluate to false.
440 * A few notes about usage:
442 * * Generally, __predict_false() error condition checks (unless
443 * you have some _strong_ reason to do otherwise, in which case
444 * document it), and/or __predict_true() `no-error' condition
445 * checks, assuming you want to optimize for the no-error case.
447 * * Other than that, if you don't know the likelihood of a test
448 * succeeding from empirical or other `hard' evidence, don't
451 * * These are meant to be used in places that are run `a lot'.
452 * It is wasteful to make predictions in code that is run
453 * seldomly (e.g. at subsystem initialization time) as the
454 * basic block reordering that this affects can often generate
457 #if __GNUC_PREREQ__(2, 96)
458 #define __predict_true(exp) __builtin_expect((exp), 1)
459 #define __predict_false(exp) __builtin_expect((exp), 0)
461 #define __predict_true(exp) (exp)
462 #define __predict_false(exp) (exp)
465 #if __GNUC_PREREQ__(4, 0)
466 #define __null_sentinel __attribute__((__sentinel__))
467 #define __exported __attribute__((__visibility__("default")))
468 #define __hidden __attribute__((__visibility__("hidden")))
470 #define __null_sentinel
476 * We define this here since <stddef.h>, <sys/queue.h>, and <sys/types.h>
479 #if __GNUC_PREREQ__(4, 1)
480 #define __offsetof(type, field) __builtin_offsetof(type, field)
483 #define __offsetof(type, field) \
484 ((__size_t)(__uintptr_t)((const volatile void *)&((type *)0)->field))
486 #define __offsetof(type, field) \
487 (__offsetof__ (reinterpret_cast <__size_t> \
488 (&reinterpret_cast <const volatile char &> \
489 (static_cast<type *> (0)->field))))
492 #define __rangeof(type, start, end) \
493 (__offsetof(type, end) - __offsetof(type, start))
496 * Given the pointer x to the member m of the struct s, return
497 * a pointer to the containing structure. When using GCC, we first
498 * assign pointer x to a local variable, to check that its type is
499 * compatible with member m.
501 #if __GNUC_PREREQ__(3, 1)
502 #define __containerof(x, s, m) ({ \
503 const volatile __typeof(((s *)0)->m) *__x = (x); \
504 __DEQUALIFY(s *, (const volatile char *)__x - __offsetof(s, m));\
507 #define __containerof(x, s, m) \
508 __DEQUALIFY(s *, (const volatile char *)(x) - __offsetof(s, m))
512 * Compiler-dependent macros to declare that functions take printf-like
513 * or scanf-like arguments. They are null except for versions of gcc
514 * that are known to support the features properly (old versions of gcc-2
515 * didn't permit keeping the keywords out of the application namespace).
517 #if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER)
518 #define __printflike(fmtarg, firstvararg)
519 #define __scanflike(fmtarg, firstvararg)
520 #define __format_arg(fmtarg)
521 #define __strfmonlike(fmtarg, firstvararg)
522 #define __strftimelike(fmtarg, firstvararg)
524 #define __printflike(fmtarg, firstvararg) \
525 __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
526 #define __scanflike(fmtarg, firstvararg) \
527 __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
528 #define __format_arg(fmtarg) __attribute__((__format_arg__ (fmtarg)))
529 #define __strfmonlike(fmtarg, firstvararg) \
530 __attribute__((__format__ (__strfmon__, fmtarg, firstvararg)))
531 #define __strftimelike(fmtarg, firstvararg) \
532 __attribute__((__format__ (__strftime__, fmtarg, firstvararg)))
535 /* Compiler-dependent macros that rely on FreeBSD-specific extensions. */
536 #if defined(__FreeBSD_cc_version) && __FreeBSD_cc_version >= 300001 && \
537 defined(__GNUC__) && !defined(__INTEL_COMPILER)
538 #define __printf0like(fmtarg, firstvararg) \
539 __attribute__((__format__ (__printf0__, fmtarg, firstvararg)))
541 #define __printf0like(fmtarg, firstvararg)
544 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
545 #ifndef __INTEL_COMPILER
546 #define __strong_reference(sym,aliassym) \
547 extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym)))
550 #define __weak_reference(sym,alias) \
551 __asm__(".weak " #alias); \
552 __asm__(".equ " #alias ", " #sym)
553 #define __warn_references(sym,msg) \
554 __asm__(".section .gnu.warning." #sym); \
555 __asm__(".asciz \"" msg "\""); \
557 #define __sym_compat(sym,impl,verid) \
558 __asm__(".symver " #impl ", " #sym "@" #verid)
559 #define __sym_default(sym,impl,verid) \
560 __asm__(".symver " #impl ", " #sym "@@@" #verid)
562 #define __weak_reference(sym,alias) \
563 __asm__(".weak alias"); \
564 __asm__(".equ alias, sym")
565 #define __warn_references(sym,msg) \
566 __asm__(".section .gnu.warning.sym"); \
567 __asm__(".asciz \"msg\""); \
569 #define __sym_compat(sym,impl,verid) \
570 __asm__(".symver impl, sym@verid")
571 #define __sym_default(impl,sym,verid) \
572 __asm__(".symver impl, sym@@@verid")
573 #endif /* __STDC__ */
574 #endif /* __GNUC__ || __INTEL_COMPILER */
576 #define __GLOBL1(sym) __asm__(".globl " #sym)
577 #define __GLOBL(sym) __GLOBL1(sym)
579 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
580 #define __IDSTRING(name,string) __asm__(".ident\t\"" string "\"")
583 * The following definition might not work well if used in header files,
584 * but it should be better than nothing. If you want a "do nothing"
585 * version, then it should generate some harmless declaration, such as:
586 * #define __IDSTRING(name,string) struct __hack
588 #define __IDSTRING(name,string) static const char name[] __unused = string
592 * Embed the rcs id of a source file in the resulting library. Note that in
593 * more recent ELF binutils, we use .ident allowing the ID to be stripped.
595 * __FBSDID("$FreeBSD$");
598 #if !defined(STRIP_FBSDID)
599 #define __FBSDID(s) __IDSTRING(__CONCAT(__rcsid_,__LINE__),s)
601 #define __FBSDID(s) struct __hack
607 #define __RCSID(s) __IDSTRING(__CONCAT(__rcsid_,__LINE__),s)
609 #define __RCSID(s) struct __hack
613 #ifndef __RCSID_SOURCE
614 #ifndef NO__RCSID_SOURCE
615 #define __RCSID_SOURCE(s) __IDSTRING(__CONCAT(__rcsid_source_,__LINE__),s)
617 #define __RCSID_SOURCE(s) struct __hack
623 #define __SCCSID(s) __IDSTRING(__CONCAT(__sccsid_,__LINE__),s)
625 #define __SCCSID(s) struct __hack
630 #ifndef NO__COPYRIGHT
631 #define __COPYRIGHT(s) __IDSTRING(__CONCAT(__copyright_,__LINE__),s)
633 #define __COPYRIGHT(s) struct __hack
638 #define __DECONST(type, var) ((type)(__uintptr_t)(const void *)(var))
642 #define __DEVOLATILE(type, var) ((type)(__uintptr_t)(volatile void *)(var))
646 #define __DEQUALIFY(type, var) ((type)(__uintptr_t)(const volatile void *)(var))
650 * The following definitions are an extension of the behavior originally
651 * implemented in <sys/_posix.h>, but with a different level of granularity.
652 * POSIX.1 requires that the macros we test be defined before any standard
653 * header file is included.
655 * Here's a quick run-down of the versions:
656 * defined(_POSIX_SOURCE) 1003.1-1988
657 * _POSIX_C_SOURCE == 1 1003.1-1990
658 * _POSIX_C_SOURCE == 2 1003.2-1992 C Language Binding Option
659 * _POSIX_C_SOURCE == 199309 1003.1b-1993
660 * _POSIX_C_SOURCE == 199506 1003.1c-1995, 1003.1i-1995,
661 * and the omnibus ISO/IEC 9945-1: 1996
662 * _POSIX_C_SOURCE == 200112 1003.1-2001
663 * _POSIX_C_SOURCE == 200809 1003.1-2008
665 * In addition, the X/Open Portability Guide, which is now the Single UNIX
666 * Specification, defines a feature-test macro which indicates the version of
667 * that specification, and which subsumes _POSIX_C_SOURCE.
669 * Our macros begin with two underscores to avoid namespace screwage.
672 /* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */
673 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 1
674 #undef _POSIX_C_SOURCE /* Probably illegal, but beyond caring now. */
675 #define _POSIX_C_SOURCE 199009
678 /* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */
679 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 2
680 #undef _POSIX_C_SOURCE
681 #define _POSIX_C_SOURCE 199209
684 /* Deal with various X/Open Portability Guides and Single UNIX Spec. */
686 #if _XOPEN_SOURCE - 0 >= 700
687 #define __XSI_VISIBLE 700
688 #undef _POSIX_C_SOURCE
689 #define _POSIX_C_SOURCE 200809
690 #elif _XOPEN_SOURCE - 0 >= 600
691 #define __XSI_VISIBLE 600
692 #undef _POSIX_C_SOURCE
693 #define _POSIX_C_SOURCE 200112
694 #elif _XOPEN_SOURCE - 0 >= 500
695 #define __XSI_VISIBLE 500
696 #undef _POSIX_C_SOURCE
697 #define _POSIX_C_SOURCE 199506
702 * Deal with all versions of POSIX. The ordering relative to the tests above is
705 #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
706 #define _POSIX_C_SOURCE 198808
708 #ifdef _POSIX_C_SOURCE
709 #if _POSIX_C_SOURCE >= 200809
710 #define __POSIX_VISIBLE 200809
711 #define __ISO_C_VISIBLE 1999
712 #elif _POSIX_C_SOURCE >= 200112
713 #define __POSIX_VISIBLE 200112
714 #define __ISO_C_VISIBLE 1999
715 #elif _POSIX_C_SOURCE >= 199506
716 #define __POSIX_VISIBLE 199506
717 #define __ISO_C_VISIBLE 1990
718 #elif _POSIX_C_SOURCE >= 199309
719 #define __POSIX_VISIBLE 199309
720 #define __ISO_C_VISIBLE 1990
721 #elif _POSIX_C_SOURCE >= 199209
722 #define __POSIX_VISIBLE 199209
723 #define __ISO_C_VISIBLE 1990
724 #elif _POSIX_C_SOURCE >= 199009
725 #define __POSIX_VISIBLE 199009
726 #define __ISO_C_VISIBLE 1990
728 #define __POSIX_VISIBLE 198808
729 #define __ISO_C_VISIBLE 0
730 #endif /* _POSIX_C_SOURCE */
733 * Deal with _ANSI_SOURCE:
734 * If it is defined, and no other compilation environment is explicitly
735 * requested, then define our internal feature-test macros to zero. This
736 * makes no difference to the preprocessor (undefined symbols in preprocessing
737 * expressions are defined to have value zero), but makes it more convenient for
738 * a test program to print out the values.
740 * If a program mistakenly defines _ANSI_SOURCE and some other macro such as
741 * _POSIX_C_SOURCE, we will assume that it wants the broader compilation
742 * environment (and in fact we will never get here).
744 #if defined(_ANSI_SOURCE) /* Hide almost everything. */
745 #define __POSIX_VISIBLE 0
746 #define __XSI_VISIBLE 0
747 #define __BSD_VISIBLE 0
748 #define __ISO_C_VISIBLE 1990
749 #define __EXT1_VISIBLE 0
750 #elif defined(_C99_SOURCE) /* Localism to specify strict C99 env. */
751 #define __POSIX_VISIBLE 0
752 #define __XSI_VISIBLE 0
753 #define __BSD_VISIBLE 0
754 #define __ISO_C_VISIBLE 1999
755 #define __EXT1_VISIBLE 0
756 #elif defined(_C11_SOURCE) /* Localism to specify strict C11 env. */
757 #define __POSIX_VISIBLE 0
758 #define __XSI_VISIBLE 0
759 #define __BSD_VISIBLE 0
760 #define __ISO_C_VISIBLE 2011
761 #define __EXT1_VISIBLE 0
762 #else /* Default environment: show everything. */
763 #define __POSIX_VISIBLE 200809
764 #define __XSI_VISIBLE 700
765 #define __BSD_VISIBLE 1
766 #define __ISO_C_VISIBLE 2011
767 #define __EXT1_VISIBLE 1
771 /* User override __EXT1_VISIBLE */
772 #if defined(__STDC_WANT_LIB_EXT1__)
773 #undef __EXT1_VISIBLE
774 #if __STDC_WANT_LIB_EXT1__
775 #define __EXT1_VISIBLE 1
777 #define __EXT1_VISIBLE 0
779 #endif /* __STDC_WANT_LIB_EXT1__ */
781 #if defined(__mips) || defined(__riscv) || \
782 (defined(__powerpc64__) && (!defined(_CALL_ELF) || _CALL_ELF == 1))
787 * Old versions of GCC use non-standard ARM arch symbols; acle-compat.h
788 * translates them to __ARM_ARCH and the modern feature symbols defined by ARM.
790 #if defined(__arm__) && !defined(__ARM_ARCH)
791 #include <machine/acle-compat.h>
795 * Nullability qualifiers: currently only supported by Clang.
797 #if !(defined(__clang__) && __has_feature(nullability))
800 #define _Null_unspecified
801 #define __NULLABILITY_PRAGMA_PUSH
802 #define __NULLABILITY_PRAGMA_POP
804 #define __NULLABILITY_PRAGMA_PUSH _Pragma("clang diagnostic push") \
805 _Pragma("clang diagnostic ignored \"-Wnullability-completeness\"")
806 #define __NULLABILITY_PRAGMA_POP _Pragma("clang diagnostic pop")
810 * Type Safety Checking
812 * Clang provides additional attributes to enable checking type safety
813 * properties that cannot be enforced by the C type system.
816 #if __has_attribute(__argument_with_type_tag__) && \
817 __has_attribute(__type_tag_for_datatype__)
818 #define __arg_type_tag(arg_kind, arg_idx, type_tag_idx) \
819 __attribute__((__argument_with_type_tag__(arg_kind, arg_idx, type_tag_idx)))
820 #define __datatype_type_tag(kind, type) \
821 __attribute__((__type_tag_for_datatype__(kind, type)))
823 #define __arg_type_tag(arg_kind, arg_idx, type_tag_idx)
824 #define __datatype_type_tag(kind, type)
830 * Clang provides support for doing basic thread-safety tests at
831 * compile-time, by marking which locks will/should be held when
832 * entering/leaving a functions.
834 * Furthermore, it is also possible to annotate variables and structure
835 * members to enforce that they are only accessed when certain locks are
839 #if __has_extension(c_thread_safety_attributes)
840 #define __lock_annotate(x) __attribute__((x))
842 #define __lock_annotate(x)
845 /* Structure implements a lock. */
846 #define __lockable __lock_annotate(lockable)
848 /* Function acquires an exclusive or shared lock. */
849 #define __locks_exclusive(...) \
850 __lock_annotate(exclusive_lock_function(__VA_ARGS__))
851 #define __locks_shared(...) \
852 __lock_annotate(shared_lock_function(__VA_ARGS__))
854 /* Function attempts to acquire an exclusive or shared lock. */
855 #define __trylocks_exclusive(...) \
856 __lock_annotate(exclusive_trylock_function(__VA_ARGS__))
857 #define __trylocks_shared(...) \
858 __lock_annotate(shared_trylock_function(__VA_ARGS__))
860 /* Function releases a lock. */
861 #define __unlocks(...) __lock_annotate(unlock_function(__VA_ARGS__))
863 /* Function asserts that an exclusive or shared lock is held. */
864 #define __asserts_exclusive(...) \
865 __lock_annotate(assert_exclusive_lock(__VA_ARGS__))
866 #define __asserts_shared(...) \
867 __lock_annotate(assert_shared_lock(__VA_ARGS__))
869 /* Function requires that an exclusive or shared lock is or is not held. */
870 #define __requires_exclusive(...) \
871 __lock_annotate(exclusive_locks_required(__VA_ARGS__))
872 #define __requires_shared(...) \
873 __lock_annotate(shared_locks_required(__VA_ARGS__))
874 #define __requires_unlocked(...) \
875 __lock_annotate(locks_excluded(__VA_ARGS__))
877 /* Function should not be analyzed. */
878 #define __no_lock_analysis __lock_annotate(no_thread_safety_analysis)
881 * Function or variable should not be sanitized, i.e. by AddressSanitizer.
882 * GCC has the nosanitize attribute, but as a function attribute only, and
883 * warns on use as a variable attribute.
885 #if __has_attribute(no_sanitize) && defined(__clang__)
886 #define __nosanitizeaddress __attribute__((no_sanitize("address")))
887 #define __nosanitizethread __attribute__((no_sanitize("thread")))
889 #define __nosanitizeaddress
890 #define __nosanitizethread
893 /* Guard variables and structure members by lock. */
894 #define __guarded_by(x) __lock_annotate(guarded_by(x))
895 #define __pt_guarded_by(x) __lock_annotate(pt_guarded_by(x))
897 #endif /* !_SYS_CDEFS_H_ */