xref: /illumos-gate/usr/src/boot/sys/sys/cdefs.h (revision 199767f8)
1 /*-
2  * Copyright (c) 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Berkeley Software Design, Inc.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
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.
19  *
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
30  * SUCH DAMAGE.
31  *
32  *	@(#)cdefs.h	8.8 (Berkeley) 1/9/95
33  * $FreeBSD$
34  */
35 
36 #ifndef	_SYS_CDEFS_H_
37 #define	_SYS_CDEFS_H_
38 
39 /*
40  * Testing against Clang-specific extensions.
41  */
42 #ifndef	__has_attribute
43 #define	__has_attribute(x)	0
44 #endif
45 #ifndef	__has_extension
46 #define	__has_extension		__has_feature
47 #endif
48 #ifndef	__has_feature
49 #define	__has_feature(x)	0
50 #endif
51 #ifndef	__has_include
52 #define	__has_include(x)	0
53 #endif
54 #ifndef	__has_builtin
55 #define	__has_builtin(x)	0
56 #endif
57 
58 #if defined(__cplusplus)
59 #define	__BEGIN_DECLS	extern "C" {
60 #define	__END_DECLS	}
61 #else
62 #define	__BEGIN_DECLS
63 #define	__END_DECLS
64 #endif
65 
66 /*
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.
70  */
71 
72 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
73 
74 #if __GNUC__ >= 3 || defined(__INTEL_COMPILER)
75 #define	__GNUCLIKE_ASM 3
76 #define	__GNUCLIKE_MATH_BUILTIN_CONSTANTS
77 #else
78 #define	__GNUCLIKE_ASM 2
79 #endif
80 #define	__GNUCLIKE___TYPEOF 1
81 #define	__GNUCLIKE___OFFSETOF 1
82 #define	__GNUCLIKE___SECTION 1
83 
84 #ifndef __INTEL_COMPILER
85 #define	__GNUCLIKE_CTOR_SECTION_HANDLING 1
86 #endif
87 
88 #define	__GNUCLIKE_BUILTIN_CONSTANT_P 1
89 #if defined(__INTEL_COMPILER) && defined(__cplusplus) && \
90    __INTEL_COMPILER < 800
91 #undef __GNUCLIKE_BUILTIN_CONSTANT_P
92 #endif
93 
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
98 #endif
99 
100 #if defined(__GNUC__)
101 #define	__GNUC_VA_LIST_COMPATIBILITY 1
102 #endif
103 
104 /*
105  * Compiler memory barriers, specific to gcc and clang.
106  */
107 #if defined(__GNUC__)
108 #define	__compiler_membar()	__asm __volatile(" " : : : "memory")
109 #endif
110 
111 #ifndef __INTEL_COMPILER
112 #define	__GNUCLIKE_BUILTIN_NEXT_ARG 1
113 #define	__GNUCLIKE_MATH_BUILTIN_RELOPS
114 #endif
115 
116 #define	__GNUCLIKE_BUILTIN_MEMCPY 1
117 
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
122 
123 #define	__CC_SUPPORTS___FUNC__ 1
124 #define	__CC_SUPPORTS_WARNING 1
125 
126 #define	__CC_SUPPORTS_VARADIC_XXX 1 /* see varargs.h */
127 
128 #define	__CC_SUPPORTS_DYNAMIC_ARRAY_INIT 1
129 
130 #endif /* __GNUC__ || __INTEL_COMPILER */
131 
132 /*
133  * Macro to test if we're using a specific version of gcc or later.
134  */
135 #if defined(__GNUC__) && !defined(__INTEL_COMPILER)
136 #define	__GNUC_PREREQ__(ma, mi)	\
137 	(__GNUC__ > (ma) || __GNUC__ == (ma) && __GNUC_MINOR__ >= (mi))
138 #else
139 #define	__GNUC_PREREQ__(ma, mi)	0
140 #endif
141 
142 /*
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.
150  *
151  * __XSTRING is like __STRING, but it expands any macros in its argument
152  * first.  It is only available with ANSI C.
153  */
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 */
160 
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 */
166 #else
167 #if !(defined(__CC_SUPPORTS___INLINE))
168 #define	__inline			/* delete GCC keyword */
169 #endif /* ! __CC_SUPPORTS___INLINE */
170 #endif /* !__cplusplus */
171 
172 #else	/* !(__STDC__ || __cplusplus) */
173 #define	__P(protos)	()		/* traditional C preprocessor */
174 #define	__CONCAT(x,y)	x/**/y
175 #define	__STRING(x)	"x"
176 
177 #if !defined(__CC_SUPPORTS___INLINE)
178 #define	__const				/* delete pseudo-ANSI C keywords */
179 #define	__inline
180 #define	__signed
181 #define	__volatile
182 /*
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.
189  */
190 #ifndef	NO_ANSI_KEYWORDS
191 #define	const				/* delete ANSI C keywords */
192 #define	inline
193 #define	signed
194 #define	volatile
195 #endif	/* !NO_ANSI_KEYWORDS */
196 #endif	/* !__CC_SUPPORTS___INLINE */
197 #endif	/* !(__STDC__ || __cplusplus) */
198 
199 /*
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.
207  */
208 #ifdef lint
209 #define	__dead2
210 #define	__pure2
211 #define	__unused
212 #define	__packed
213 #define	__aligned(x)
214 #define	__alloc_align(x)
215 #define	__alloc_size(x)
216 #define	__section(x)
217 #define	__weak_symbol
218 #else
219 #define	__weak_symbol	__attribute__((__weak__))
220 #if !__GNUC_PREREQ__(2, 5) && !defined(__INTEL_COMPILER)
221 #define	__dead2
222 #define	__pure2
223 #define	__unused
224 #endif
225 #if __GNUC__ == 2 && __GNUC_MINOR__ >= 5 && __GNUC_MINOR__ < 7 && !defined(__INTEL_COMPILER)
226 #define	__dead2		__attribute__((__noreturn__))
227 #define	__pure2		__attribute__((__const__))
228 #define	__unused
229 /* XXX Find out what to do for __packed, __aligned and __section */
230 #endif
231 #if __GNUC_PREREQ__(2, 7) || defined(__INTEL_COMPILER)
232 #define	__dead2		__attribute__((__noreturn__))
233 #define	__pure2		__attribute__((__const__))
234 #define	__unused	__attribute__((__unused__))
235 #define	__used		__attribute__((__used__))
236 #define	__packed	__attribute__((__packed__))
237 #define	__aligned(x)	__attribute__((__aligned__(x)))
238 #define	__section(x)	__attribute__((__section__(x)))
239 #endif
240 #if __GNUC_PREREQ__(4, 3) || __has_attribute(__alloc_size__)
241 #define	__alloc_size(x)	__attribute__((__alloc_size__(x)))
242 #else
243 #define	__alloc_size(x)
244 #endif
245 #if __GNUC_PREREQ__(4, 9) || __has_attribute(__alloc_align__)
246 #define	__alloc_align(x)	__attribute__((__alloc_align__(x)))
247 #else
248 #define	__alloc_align(x)
249 #endif
250 #endif /* lint */
251 
252 #if !__GNUC_PREREQ__(2, 95)
253 #define	__alignof(x)	__offsetof(struct { char __a; x __b; }, __b)
254 #endif
255 
256 /*
257  * Keywords added in C11.
258  */
259 
260 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L || defined(lint)
261 
262 #if !__has_extension(c_alignas)
263 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
264     __has_extension(cxx_alignas)
265 #define	_Alignas(x)		alignas(x)
266 #else
267 /* XXX: Only emulates _Alignas(constant-expression); not _Alignas(type-name). */
268 #define	_Alignas(x)		__aligned(x)
269 #endif
270 #endif
271 
272 #if defined(__cplusplus) && __cplusplus >= 201103L
273 #define	_Alignof(x)		alignof(x)
274 #else
275 #define	_Alignof(x)		__alignof(x)
276 #endif
277 
278 #if !__has_extension(c_atomic) && !__has_extension(cxx_atomic)
279 /*
280  * No native support for _Atomic(). Place object in structure to prevent
281  * most forms of direct non-atomic access.
282  */
283 #define	_Atomic(T)		struct { T volatile __val; }
284 #endif
285 
286 #if defined(__cplusplus) && __cplusplus >= 201103L
287 #define	_Noreturn		[[noreturn]]
288 #else
289 #define	_Noreturn		__dead2
290 #endif
291 
292 #if !__has_extension(c_static_assert)
293 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
294     __has_extension(cxx_static_assert)
295 #define	_Static_assert(x, y)	static_assert(x, y)
296 #elif __GNUC_PREREQ__(4,6)
297 /* Nothing, gcc 4.6 and higher has _Static_assert built-in */
298 #elif defined(__COUNTER__)
299 #define	_Static_assert(x, y)	__Static_assert(x, __COUNTER__)
300 #define	__Static_assert(x, y)	___Static_assert(x, y)
301 #define	___Static_assert(x, y)	typedef char __assert_ ## y[(x) ? 1 : -1] \
302 				__unused
303 #else
304 #define	_Static_assert(x, y)	struct __hack
305 #endif
306 #endif
307 
308 #if !__has_extension(c_thread_local)
309 /*
310  * XXX: Some compilers (Clang 3.3, GCC 4.7) falsely announce C++11 mode
311  * without actually supporting the thread_local keyword. Don't check for
312  * the presence of C++11 when defining _Thread_local.
313  */
314 #if /* (defined(__cplusplus) && __cplusplus >= 201103L) || */ \
315     __has_extension(cxx_thread_local)
316 #define	_Thread_local		thread_local
317 #else
318 #define	_Thread_local		__thread
319 #endif
320 #endif
321 
322 #endif /* __STDC_VERSION__ || __STDC_VERSION__ < 201112L */
323 
324 /*
325  * Emulation of C11 _Generic().  Unlike the previously defined C11
326  * keywords, it is not possible to implement this using exactly the same
327  * syntax.  Therefore implement something similar under the name
328  * __generic().  Unlike _Generic(), this macro can only distinguish
329  * between a single type, so it requires nested invocations to
330  * distinguish multiple cases.
331  */
332 
333 #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) || \
334     __has_extension(c_generic_selections)
335 #define	__generic(expr, t, yes, no)					\
336 	_Generic(expr, t: yes, default: no)
337 #elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus)
338 #define	__generic(expr, t, yes, no)					\
339 	__builtin_choose_expr(						\
340 	    __builtin_types_compatible_p(__typeof(expr), t), yes, no)
341 #endif
342 
343 #if __GNUC_PREREQ__(2, 96)
344 #define	__malloc_like	__attribute__((__malloc__))
345 #define	__pure		__attribute__((__pure__))
346 #else
347 #define	__malloc_like
348 #define	__pure
349 #endif
350 
351 #if __GNUC_PREREQ__(3, 1) || (defined(__INTEL_COMPILER) && __INTEL_COMPILER >= 800)
352 #define	__always_inline	__attribute__((__always_inline__))
353 #else
354 #define	__always_inline
355 #endif
356 
357 #if __GNUC_PREREQ__(3, 1)
358 #define	__noinline	__attribute__ ((__noinline__))
359 #else
360 #define	__noinline
361 #endif
362 
363 #if __GNUC_PREREQ__(3, 3)
364 #define	__nonnull(x)	__attribute__((__nonnull__(x)))
365 #define	__nonnull_all	__attribute__((__nonnull__))
366 #else
367 #define	__nonnull(x)
368 #define	__nonnull_all
369 #endif
370 
371 #if __GNUC_PREREQ__(3, 4)
372 #define	__fastcall	__attribute__((__fastcall__))
373 #define	__result_use_check	__attribute__((__warn_unused_result__))
374 #else
375 #define	__fastcall
376 #define	__result_use_check
377 #endif
378 
379 #if __GNUC_PREREQ__(4, 1)
380 #define	__returns_twice	__attribute__((__returns_twice__))
381 #else
382 #define	__returns_twice
383 #endif
384 
385 #if __GNUC_PREREQ__(4, 6) || __has_builtin(__builtin_unreachable)
386 #define	__unreachable()	__builtin_unreachable()
387 #else
388 #define	__unreachable()	((void)0)
389 #endif
390 
391 /* XXX: should use `#if __STDC_VERSION__ < 199901'. */
392 #if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER)
393 #define	__func__	NULL
394 #endif
395 
396 #if (defined(__INTEL_COMPILER) || (defined(__GNUC__) && __GNUC__ >= 2)) && !defined(__STRICT_ANSI__) || __STDC_VERSION__ >= 199901
397 #define	__LONG_LONG_SUPPORTED
398 #endif
399 
400 /* C++11 exposes a load of C99 stuff */
401 #if defined(__cplusplus) && __cplusplus >= 201103L
402 #define	__LONG_LONG_SUPPORTED
403 #ifndef	__STDC_LIMIT_MACROS
404 #define	__STDC_LIMIT_MACROS
405 #endif
406 #ifndef	__STDC_CONSTANT_MACROS
407 #define	__STDC_CONSTANT_MACROS
408 #endif
409 #endif
410 
411 /*
412  * GCC 2.95 provides `__restrict' as an extension to C90 to support the
413  * C99-specific `restrict' type qualifier.  We happen to use `__restrict' as
414  * a way to define the `restrict' type qualifier without disturbing older
415  * software that is unaware of C99 keywords.
416  */
417 #if !(__GNUC__ == 2 && __GNUC_MINOR__ == 95)
418 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 199901 || defined(lint)
419 #define	__restrict
420 #else
421 #define	__restrict	restrict
422 #endif
423 #endif
424 
425 /*
426  * GNU C version 2.96 adds explicit branch prediction so that
427  * the CPU back-end can hint the processor and also so that
428  * code blocks can be reordered such that the predicted path
429  * sees a more linear flow, thus improving cache behavior, etc.
430  *
431  * The following two macros provide us with a way to utilize this
432  * compiler feature.  Use __predict_true() if you expect the expression
433  * to evaluate to true, and __predict_false() if you expect the
434  * expression to evaluate to false.
435  *
436  * A few notes about usage:
437  *
438  *	* Generally, __predict_false() error condition checks (unless
439  *	  you have some _strong_ reason to do otherwise, in which case
440  *	  document it), and/or __predict_true() `no-error' condition
441  *	  checks, assuming you want to optimize for the no-error case.
442  *
443  *	* Other than that, if you don't know the likelihood of a test
444  *	  succeeding from empirical or other `hard' evidence, don't
445  *	  make predictions.
446  *
447  *	* These are meant to be used in places that are run `a lot'.
448  *	  It is wasteful to make predictions in code that is run
449  *	  seldomly (e.g. at subsystem initialization time) as the
450  *	  basic block reordering that this affects can often generate
451  *	  larger code.
452  */
453 #if __GNUC_PREREQ__(2, 96)
454 #define	__predict_true(exp)     __builtin_expect((exp), 1)
455 #define	__predict_false(exp)    __builtin_expect((exp), 0)
456 #else
457 #define	__predict_true(exp)     (exp)
458 #define	__predict_false(exp)    (exp)
459 #endif
460 
461 #if __GNUC_PREREQ__(4, 0)
462 #define	__null_sentinel	__attribute__((__sentinel__))
463 #define	__exported	__attribute__((__visibility__("default")))
464 #define	__hidden	__attribute__((__visibility__("hidden")))
465 #else
466 #define	__null_sentinel
467 #define	__exported
468 #define	__hidden
469 #endif
470 
471 /*
472  * We define this here since <stddef.h>, <sys/queue.h>, and <sys/types.h>
473  * require it.
474  */
475 #if __GNUC_PREREQ__(4, 1)
476 #define	__offsetof(type, field)	 __builtin_offsetof(type, field)
477 #else
478 #ifndef __cplusplus
479 #define	__offsetof(type, field) \
480 	((__size_t)(__uintptr_t)((const volatile void *)&((type *)0)->field))
481 #else
482 #define	__offsetof(type, field)					\
483   (__offsetof__ (reinterpret_cast <__size_t>			\
484                  (&reinterpret_cast <const volatile char &>	\
485                   (static_cast<type *> (0)->field))))
486 #endif
487 #endif
488 #define	__rangeof(type, start, end) \
489 	(__offsetof(type, end) - __offsetof(type, start))
490 
491 /*
492  * Given the pointer x to the member m of the struct s, return
493  * a pointer to the containing structure.  When using GCC, we first
494  * assign pointer x to a local variable, to check that its type is
495  * compatible with member m.
496  */
497 #if __GNUC_PREREQ__(3, 1)
498 #define	__containerof(x, s, m) ({					\
499 	const volatile __typeof(((s *)0)->m) *__x = (x);		\
500 	__DEQUALIFY(s *, (const volatile char *)__x - __offsetof(s, m));\
501 })
502 #else
503 #define	__containerof(x, s, m)						\
504 	__DEQUALIFY(s *, (const volatile char *)(x) - __offsetof(s, m))
505 #endif
506 
507 /*
508  * Compiler-dependent macros to declare that functions take printf-like
509  * or scanf-like arguments.  They are null except for versions of gcc
510  * that are known to support the features properly (old versions of gcc-2
511  * didn't permit keeping the keywords out of the application namespace).
512  */
513 #if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER)
514 #define	__printflike(fmtarg, firstvararg)
515 #define	__scanflike(fmtarg, firstvararg)
516 #define	__format_arg(fmtarg)
517 #define	__strfmonlike(fmtarg, firstvararg)
518 #define	__strftimelike(fmtarg, firstvararg)
519 #else
520 #define	__printflike(fmtarg, firstvararg) \
521 	    __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
522 #define	__scanflike(fmtarg, firstvararg) \
523 	    __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
524 #define	__format_arg(fmtarg)	__attribute__((__format_arg__ (fmtarg)))
525 #define	__strfmonlike(fmtarg, firstvararg) \
526 	    __attribute__((__format__ (__strfmon__, fmtarg, firstvararg)))
527 #define	__strftimelike(fmtarg, firstvararg) \
528 	    __attribute__((__format__ (__strftime__, fmtarg, firstvararg)))
529 #endif
530 
531 /*
532  * FORTIFY_SOURCE, and perhaps other compiler-specific features, require
533  * the use of non-standard inlining.  In general we should try to avoid
534  * using these but GCC-compatible compilers tend to support the extensions
535  * well enough to use them in limited cases.
536  */
537 #if defined(__GNUC_GNU_INLINE__) || defined(__GNUC_STDC_INLINE__)
538 #if __GNUC_PREREQ__(4, 3) || __has_attribute(__artificial__)
539 #define	__gnu_inline	__attribute__((__gnu_inline__, __artificial__))
540 #else
541 #define	__gnu_inline	__attribute__((__gnu_inline__))
542 #endif /* artificial */
543 #else
544 #define	__gnu_inline
545 #endif
546 
547 /* Compiler-dependent macros that rely on FreeBSD-specific extensions. */
548 #if defined(__FreeBSD_cc_version) && __FreeBSD_cc_version >= 300001 && \
549     defined(__GNUC__) && !defined(__INTEL_COMPILER)
550 #define	__printf0like(fmtarg, firstvararg) \
551 	    __attribute__((__format__ (__printf0__, fmtarg, firstvararg)))
552 #else
553 #define	__printf0like(fmtarg, firstvararg)
554 #endif
555 
556 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
557 #ifndef __INTEL_COMPILER
558 #define	__strong_reference(sym,aliassym)	\
559 	extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym)))
560 #endif
561 #ifdef __STDC__
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 "\"");	\
568 	__asm__(".previous")
569 #define	__sym_compat(sym,impl,verid)	\
570 	__asm__(".symver " #impl ", " #sym "@" #verid)
571 #define	__sym_default(sym,impl,verid)	\
572 	__asm__(".symver " #impl ", " #sym "@@" #verid)
573 #else
574 #define	__weak_reference(sym,alias)	\
575 	__asm__(".weak alias");		\
576 	__asm__(".equ alias, sym")
577 #define	__warn_references(sym,msg)	\
578 	__asm__(".section .gnu.warning.sym"); \
579 	__asm__(".asciz \"msg\"");	\
580 	__asm__(".previous")
581 #define	__sym_compat(sym,impl,verid)	\
582 	__asm__(".symver impl, sym@verid")
583 #define	__sym_default(impl,sym,verid)	\
584 	__asm__(".symver impl, sym@@verid")
585 #endif	/* __STDC__ */
586 #endif	/* __GNUC__ || __INTEL_COMPILER */
587 
588 #define	__GLOBL1(sym)	__asm__(".globl " #sym)
589 #define	__GLOBL(sym)	__GLOBL1(sym)
590 
591 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
592 #define	__IDSTRING(name,string)	__asm__(".ident\t\"" string "\"")
593 #else
594 /*
595  * The following definition might not work well if used in header files,
596  * but it should be better than nothing.  If you want a "do nothing"
597  * version, then it should generate some harmless declaration, such as:
598  *    #define	__IDSTRING(name,string)	struct __hack
599  */
600 #define	__IDSTRING(name,string)	static const char name[] __unused = string
601 #endif
602 
603 /*
604  * Embed the rcs id of a source file in the resulting library.  Note that in
605  * more recent ELF binutils, we use .ident allowing the ID to be stripped.
606  * Usage:
607  *	__FBSDID("$FreeBSD$");
608  */
609 #ifndef	__FBSDID
610 #if !defined(lint) && !defined(STRIP_FBSDID)
611 #define	__FBSDID(s)	__IDSTRING(__CONCAT(__rcsid_,__LINE__),s)
612 #else
613 #define	__FBSDID(s)	struct __hack
614 #endif
615 #endif
616 
617 #ifndef	__RCSID
618 #ifndef	NO__RCSID
619 #define	__RCSID(s)	__IDSTRING(__CONCAT(__rcsid_,__LINE__),s)
620 #else
621 #define	__RCSID(s)	struct __hack
622 #endif
623 #endif
624 
625 #ifndef	__RCSID_SOURCE
626 #ifndef	NO__RCSID_SOURCE
627 #define	__RCSID_SOURCE(s)	__IDSTRING(__CONCAT(__rcsid_source_,__LINE__),s)
628 #else
629 #define	__RCSID_SOURCE(s)	struct __hack
630 #endif
631 #endif
632 
633 #ifndef	__SCCSID
634 #ifndef	NO__SCCSID
635 #define	__SCCSID(s)	__IDSTRING(__CONCAT(__sccsid_,__LINE__),s)
636 #else
637 #define	__SCCSID(s)	struct __hack
638 #endif
639 #endif
640 
641 #ifndef	__COPYRIGHT
642 #ifndef	NO__COPYRIGHT
643 #define	__COPYRIGHT(s)	__IDSTRING(__CONCAT(__copyright_,__LINE__),s)
644 #else
645 #define	__COPYRIGHT(s)	struct __hack
646 #endif
647 #endif
648 
649 #ifndef	__DECONST
650 #define	__DECONST(type, var)	((type)(__uintptr_t)(const void *)(var))
651 #endif
652 
653 #ifndef	__DEVOLATILE
654 #define	__DEVOLATILE(type, var)	((type)(__uintptr_t)(volatile void *)(var))
655 #endif
656 
657 #ifndef	__DEQUALIFY
658 #define	__DEQUALIFY(type, var)	((type)(__uintptr_t)(const volatile void *)(var))
659 #endif
660 
661 /*-
662  * The following definitions are an extension of the behavior originally
663  * implemented in <sys/_posix.h>, but with a different level of granularity.
664  * POSIX.1 requires that the macros we test be defined before any standard
665  * header file is included.
666  *
667  * Here's a quick run-down of the versions:
668  *  defined(_POSIX_SOURCE)		1003.1-1988
669  *  _POSIX_C_SOURCE == 1		1003.1-1990
670  *  _POSIX_C_SOURCE == 2		1003.2-1992 C Language Binding Option
671  *  _POSIX_C_SOURCE == 199309		1003.1b-1993
672  *  _POSIX_C_SOURCE == 199506		1003.1c-1995, 1003.1i-1995,
673  *					and the omnibus ISO/IEC 9945-1: 1996
674  *  _POSIX_C_SOURCE == 200112		1003.1-2001
675  *  _POSIX_C_SOURCE == 200809		1003.1-2008
676  *
677  * In addition, the X/Open Portability Guide, which is now the Single UNIX
678  * Specification, defines a feature-test macro which indicates the version of
679  * that specification, and which subsumes _POSIX_C_SOURCE.
680  *
681  * Our macros begin with two underscores to avoid namespace screwage.
682  */
683 
684 /* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */
685 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 1
686 #undef _POSIX_C_SOURCE		/* Probably illegal, but beyond caring now. */
687 #define	_POSIX_C_SOURCE		199009
688 #endif
689 
690 /* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */
691 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 2
692 #undef _POSIX_C_SOURCE
693 #define	_POSIX_C_SOURCE		199209
694 #endif
695 
696 /* Deal with various X/Open Portability Guides and Single UNIX Spec. */
697 #ifdef _XOPEN_SOURCE
698 #if _XOPEN_SOURCE - 0 >= 700
699 #define	__XSI_VISIBLE		700
700 #undef _POSIX_C_SOURCE
701 #define	_POSIX_C_SOURCE		200809
702 #elif _XOPEN_SOURCE - 0 >= 600
703 #define	__XSI_VISIBLE		600
704 #undef _POSIX_C_SOURCE
705 #define	_POSIX_C_SOURCE		200112
706 #elif _XOPEN_SOURCE - 0 >= 500
707 #define	__XSI_VISIBLE		500
708 #undef _POSIX_C_SOURCE
709 #define	_POSIX_C_SOURCE		199506
710 #endif
711 #endif
712 
713 /*
714  * Deal with all versions of POSIX.  The ordering relative to the tests above is
715  * important.
716  */
717 #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
718 #define	_POSIX_C_SOURCE		198808
719 #endif
720 #ifdef _POSIX_C_SOURCE
721 #if _POSIX_C_SOURCE >= 200809
722 #define	__POSIX_VISIBLE		200809
723 #define	__ISO_C_VISIBLE		1999
724 #elif _POSIX_C_SOURCE >= 200112
725 #define	__POSIX_VISIBLE		200112
726 #define	__ISO_C_VISIBLE		1999
727 #elif _POSIX_C_SOURCE >= 199506
728 #define	__POSIX_VISIBLE		199506
729 #define	__ISO_C_VISIBLE		1990
730 #elif _POSIX_C_SOURCE >= 199309
731 #define	__POSIX_VISIBLE		199309
732 #define	__ISO_C_VISIBLE		1990
733 #elif _POSIX_C_SOURCE >= 199209
734 #define	__POSIX_VISIBLE		199209
735 #define	__ISO_C_VISIBLE		1990
736 #elif _POSIX_C_SOURCE >= 199009
737 #define	__POSIX_VISIBLE		199009
738 #define	__ISO_C_VISIBLE		1990
739 #else
740 #define	__POSIX_VISIBLE		198808
741 #define	__ISO_C_VISIBLE		0
742 #endif /* _POSIX_C_SOURCE */
743 #else
744 /*-
745  * Deal with _ANSI_SOURCE:
746  * If it is defined, and no other compilation environment is explicitly
747  * requested, then define our internal feature-test macros to zero.  This
748  * makes no difference to the preprocessor (undefined symbols in preprocessing
749  * expressions are defined to have value zero), but makes it more convenient for
750  * a test program to print out the values.
751  *
752  * If a program mistakenly defines _ANSI_SOURCE and some other macro such as
753  * _POSIX_C_SOURCE, we will assume that it wants the broader compilation
754  * environment (and in fact we will never get here).
755  */
756 #if defined(_ANSI_SOURCE)	/* Hide almost everything. */
757 #define	__POSIX_VISIBLE		0
758 #define	__XSI_VISIBLE		0
759 #define	__BSD_VISIBLE		0
760 #define	__ISO_C_VISIBLE		1990
761 #elif defined(_C99_SOURCE)	/* Localism to specify strict C99 env. */
762 #define	__POSIX_VISIBLE		0
763 #define	__XSI_VISIBLE		0
764 #define	__BSD_VISIBLE		0
765 #define	__ISO_C_VISIBLE		1999
766 #elif defined(_C11_SOURCE)	/* Localism to specify strict C11 env. */
767 #define	__POSIX_VISIBLE		0
768 #define	__XSI_VISIBLE		0
769 #define	__BSD_VISIBLE		0
770 #define	__ISO_C_VISIBLE		2011
771 #else				/* Default environment: show everything. */
772 #define	__POSIX_VISIBLE		200809
773 #define	__XSI_VISIBLE		700
774 #define	__BSD_VISIBLE		1
775 #define	__ISO_C_VISIBLE		2011
776 #endif
777 #endif
778 
779 #if defined(__mips) || defined(__powerpc64__) || defined(__riscv__)
780 #define	__NO_TLS 1
781 #endif
782 
783 /*
784  * Type Safety Checking
785  *
786  * Clang provides additional attributes to enable checking type safety
787  * properties that cannot be enforced by the C type system.
788  */
789 
790 #if __has_attribute(__argument_with_type_tag__) && \
791     __has_attribute(__type_tag_for_datatype__) && !defined(lint)
792 #define	__arg_type_tag(arg_kind, arg_idx, type_tag_idx) \
793 	    __attribute__((__argument_with_type_tag__(arg_kind, arg_idx, type_tag_idx)))
794 #define	__datatype_type_tag(kind, type) \
795 	    __attribute__((__type_tag_for_datatype__(kind, type)))
796 #else
797 #define	__arg_type_tag(arg_kind, arg_idx, type_tag_idx)
798 #define	__datatype_type_tag(kind, type)
799 #endif
800 
801 /*
802  * Lock annotations.
803  *
804  * Clang provides support for doing basic thread-safety tests at
805  * compile-time, by marking which locks will/should be held when
806  * entering/leaving a functions.
807  *
808  * Furthermore, it is also possible to annotate variables and structure
809  * members to enforce that they are only accessed when certain locks are
810  * held.
811  */
812 
813 #if __has_extension(c_thread_safety_attributes)
814 #define	__lock_annotate(x)	__attribute__((x))
815 #else
816 #define	__lock_annotate(x)
817 #endif
818 
819 /* Structure implements a lock. */
820 #define	__lockable		__lock_annotate(lockable)
821 
822 /* Function acquires an exclusive or shared lock. */
823 #define	__locks_exclusive(...) \
824 	__lock_annotate(exclusive_lock_function(__VA_ARGS__))
825 #define	__locks_shared(...) \
826 	__lock_annotate(shared_lock_function(__VA_ARGS__))
827 
828 /* Function attempts to acquire an exclusive or shared lock. */
829 #define	__trylocks_exclusive(...) \
830 	__lock_annotate(exclusive_trylock_function(__VA_ARGS__))
831 #define	__trylocks_shared(...) \
832 	__lock_annotate(shared_trylock_function(__VA_ARGS__))
833 
834 /* Function releases a lock. */
835 #define	__unlocks(...)		__lock_annotate(unlock_function(__VA_ARGS__))
836 
837 /* Function asserts that an exclusive or shared lock is held. */
838 #define	__asserts_exclusive(...) \
839 	__lock_annotate(assert_exclusive_lock(__VA_ARGS__))
840 #define	__asserts_shared(...) \
841 	__lock_annotate(assert_shared_lock(__VA_ARGS__))
842 
843 /* Function requires that an exclusive or shared lock is or is not held. */
844 #define	__requires_exclusive(...) \
845 	__lock_annotate(exclusive_locks_required(__VA_ARGS__))
846 #define	__requires_shared(...) \
847 	__lock_annotate(shared_locks_required(__VA_ARGS__))
848 #define	__requires_unlocked(...) \
849 	__lock_annotate(locks_excluded(__VA_ARGS__))
850 
851 /* Function should not be analyzed. */
852 #define	__no_lock_analysis	__lock_annotate(no_thread_safety_analysis)
853 
854 /* Guard variables and structure members by lock. */
855 #define	__guarded_by(x)		__lock_annotate(guarded_by(x))
856 #define	__pt_guarded_by(x)	__lock_annotate(pt_guarded_by(x))
857 
858 #endif /* !_SYS_CDEFS_H_ */
859