1 /* libc/sys/linux/sys/cdefs.h - Helper macros for K&R vs. ANSI C compat. */
2 
3 /* Written 2000 by Werner Almesberger */
4 
5 /*-
6  * Copyright (c) 1991, 1993
7  *	The Regents of the University of California.  All rights reserved.
8  *
9  * This code is derived from software contributed to Berkeley by
10  * Berkeley Software Design, Inc.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)cdefs.h	8.8 (Berkeley) 1/9/95
37  * $FreeBSD$
38  */
39 
40 #ifndef	_SYS_CDEFS_H_
41 #define	_SYS_CDEFS_H_
42 
43 #include <machine/_default_types.h>
44 #include <sys/features.h>
45 #include <stddef.h>
46 
47 #define __PMT(args)	args
48 #define __DOTS    	, ...
49 #define __THROW
50 
51 #ifdef __GNUC__
52 # define __ASMNAME(cname)  __XSTRING (__USER_LABEL_PREFIX__) cname
53 #endif
54 
55 #define __ptr_t void *
56 #define __long_double_t  long double
57 
58 #define __attribute_malloc__
59 #define __attribute_pure__
60 #define __attribute_format_strfmon__(a,b)
61 #define __flexarr      [0]
62 
63 #ifndef __BOUNDED_POINTERS__
64 # define __bounded      /* nothing */
65 # define __unbounded    /* nothing */
66 # define __ptrvalue     /* nothing */
67 #endif
68 
69 /*
70  * Testing against Clang-specific extensions.
71  */
72 #ifndef	__has_attribute
73 #define	__has_attribute(x)	0
74 #endif
75 #ifndef	__has_extension
76 #define	__has_extension		__has_feature
77 #endif
78 #ifndef	__has_feature
79 #define	__has_feature(x)	0
80 #endif
81 #ifndef	__has_include
82 #define	__has_include(x)	0
83 #endif
84 #ifndef	__has_builtin
85 #define	__has_builtin(x)	0
86 #endif
87 
88 #if defined(__cplusplus)
89 #define	__BEGIN_DECLS	extern "C" {
90 #define	__END_DECLS	}
91 #else
92 #define	__BEGIN_DECLS
93 #define	__END_DECLS
94 #endif
95 
96 /*
97  * This code has been put in place to help reduce the addition of
98  * compiler specific defines in FreeBSD code.  It helps to aid in
99  * having a compiler-agnostic source tree.
100  */
101 
102 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
103 
104 #if __GNUC__ >= 3 || defined(__INTEL_COMPILER)
105 #define	__GNUCLIKE_ASM 3
106 #define	__GNUCLIKE_MATH_BUILTIN_CONSTANTS
107 #else
108 #define	__GNUCLIKE_ASM 2
109 #endif
110 #define	__GNUCLIKE___TYPEOF 1
111 #define	__GNUCLIKE___OFFSETOF 1
112 #define	__GNUCLIKE___SECTION 1
113 
114 #ifndef __INTEL_COMPILER
115 #define	__GNUCLIKE_CTOR_SECTION_HANDLING 1
116 #endif
117 
118 #define	__GNUCLIKE_BUILTIN_CONSTANT_P 1
119 #if defined(__INTEL_COMPILER) && defined(__cplusplus) && \
120    __INTEL_COMPILER < 800
121 #undef __GNUCLIKE_BUILTIN_CONSTANT_P
122 #endif
123 
124 #if (__GNUC_MINOR__ > 95 || __GNUC__ >= 3)
125 #define	__GNUCLIKE_BUILTIN_VARARGS 1
126 #define	__GNUCLIKE_BUILTIN_STDARG 1
127 #define	__GNUCLIKE_BUILTIN_VAALIST 1
128 #endif
129 
130 #if defined(__GNUC__)
131 #define	__GNUC_VA_LIST_COMPATIBILITY 1
132 #endif
133 
134 /*
135  * Compiler memory barriers, specific to gcc and clang.
136  */
137 #if defined(__GNUC__)
138 #define	__compiler_membar()	__asm __volatile(" " : : : "memory")
139 #endif
140 
141 #ifndef __INTEL_COMPILER
142 #define	__GNUCLIKE_BUILTIN_NEXT_ARG 1
143 #define	__GNUCLIKE_MATH_BUILTIN_RELOPS
144 #endif
145 
146 #define	__GNUCLIKE_BUILTIN_MEMCPY 1
147 
148 /* XXX: if __GNUC__ >= 2: not tested everywhere originally, where replaced */
149 #define	__CC_SUPPORTS_INLINE 1
150 #define	__CC_SUPPORTS___INLINE 1
151 #define	__CC_SUPPORTS___INLINE__ 1
152 
153 #define	__CC_SUPPORTS___FUNC__ 1
154 #define	__CC_SUPPORTS_WARNING 1
155 
156 #define	__CC_SUPPORTS_VARADIC_XXX 1 /* see varargs.h */
157 
158 #define	__CC_SUPPORTS_DYNAMIC_ARRAY_INIT 1
159 
160 #endif /* __GNUC__ || __INTEL_COMPILER */
161 
162 /*
163  * The __CONCAT macro is used to concatenate parts of symbol names, e.g.
164  * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo.
165  * The __CONCAT macro is a bit tricky to use if it must work in non-ANSI
166  * mode -- there must be no spaces between its arguments, and for nested
167  * __CONCAT's, all the __CONCAT's must be at the left.  __CONCAT can also
168  * concatenate double-quoted strings produced by the __STRING macro, but
169  * this only works with ANSI C.
170  *
171  * __XSTRING is like __STRING, but it expands any macros in its argument
172  * first.  It is only available with ANSI C.
173  */
174 #if defined(__STDC__) || defined(__cplusplus)
175 #define	__P(protos)	protos		/* full-blown ANSI C */
176 #define	__CONCAT1(x,y)	x ## y
177 #define	__CONCAT(x,y)	__CONCAT1(x,y)
178 #define	__STRING(x)	#x		/* stringify without expanding x */
179 #define	__XSTRING(x)	__STRING(x)	/* expand x, then stringify */
180 
181 #define	__const		const		/* define reserved names to standard */
182 #define	__signed	signed
183 #define	__volatile	volatile
184 #if defined(__cplusplus)
185 #define	__inline	inline		/* convert to C++ keyword */
186 #else
187 #if !(defined(__CC_SUPPORTS___INLINE))
188 #define	__inline			/* delete GCC keyword */
189 #endif /* ! __CC_SUPPORTS___INLINE */
190 #endif /* !__cplusplus */
191 
192 #else	/* !(__STDC__ || __cplusplus) */
193 #define	__P(protos)	()		/* traditional C preprocessor */
194 #define	__CONCAT(x,y)	x/**/y
195 #define	__STRING(x)	"x"
196 
197 #if !defined(__CC_SUPPORTS___INLINE)
198 #define	__const				/* delete pseudo-ANSI C keywords */
199 #define	__inline
200 #define	__signed
201 #define	__volatile
202 /*
203  * In non-ANSI C environments, new programs will want ANSI-only C keywords
204  * deleted from the program and old programs will want them left alone.
205  * When using a compiler other than gcc, programs using the ANSI C keywords
206  * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS.
207  * When using "gcc -traditional", we assume that this is the intent; if
208  * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone.
209  */
210 #ifndef	NO_ANSI_KEYWORDS
211 #define	const				/* delete ANSI C keywords */
212 #define	inline
213 #define	signed
214 #define	volatile
215 #endif	/* !NO_ANSI_KEYWORDS */
216 #endif	/* !__CC_SUPPORTS___INLINE */
217 #endif	/* !(__STDC__ || __cplusplus) */
218 
219 /*
220  * Compiler-dependent macros to help declare dead (non-returning) and
221  * pure (no side effects) functions, and unused variables.  They are
222  * null except for versions of gcc that are known to support the features
223  * properly (old versions of gcc-2 supported the dead and pure features
224  * in a different (wrong) way).  If we do not provide an implementation
225  * for a given compiler, let the compile fail if it is told to use
226  * a feature that we cannot live without.
227  */
228 #ifdef lint
229 #define	__dead2
230 #define	__pure2
231 #define	__unused
232 #define	__packed
233 #define	__aligned(x)
234 #define	__alloc_align(x)
235 #define	__alloc_size(x)
236 #define	__section(x)
237 #define	__weak_symbol
238 #else
239 #define	__weak_symbol	__attribute__((__weak__))
240 #if !__GNUC_PREREQ__(2, 5) && !defined(__INTEL_COMPILER)
241 #define	__dead2
242 #define	__pure2
243 #define	__unused
244 #endif
245 #if __GNUC__ == 2 && __GNUC_MINOR__ >= 5 && __GNUC_MINOR__ < 7 && !defined(__INTEL_COMPILER)
246 #define	__dead2		__attribute__((__noreturn__))
247 #define	__pure2		__attribute__((__const__))
248 #define	__unused
249 /* XXX Find out what to do for __packed, __aligned and __section */
250 #endif
251 #if __GNUC_PREREQ__(2, 7) || defined(__INTEL_COMPILER)
252 #define	__dead2		__attribute__((__noreturn__))
253 #define	__pure2		__attribute__((__const__))
254 #define	__unused	__attribute__((__unused__))
255 #define	__used		__attribute__((__used__))
256 #define	__packed	__attribute__((__packed__))
257 #define	__aligned(x)	__attribute__((__aligned__(x)))
258 #define	__section(x)	__attribute__((__section__(x)))
259 #endif
260 #if __GNUC_PREREQ__(4, 3) || __has_attribute(__alloc_size__)
261 #define	__alloc_size(x)	__attribute__((__alloc_size__(x)))
262 #else
263 #define	__alloc_size(x)
264 #endif
265 #if __GNUC_PREREQ__(4, 9) || __has_attribute(__alloc_align__)
266 #define	__alloc_align(x)	__attribute__((__alloc_align__(x)))
267 #else
268 #define	__alloc_align(x)
269 #endif
270 #endif /* lint */
271 
272 #if !__GNUC_PREREQ__(2, 95)
273 #define	__alignof(x)	__offsetof(struct { char __a; x __b; }, __b)
274 #endif
275 
276 /*
277  * Keywords added in C11.
278  */
279 
280 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L || defined(lint)
281 
282 #if !__has_extension(c_alignas)
283 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
284     __has_extension(cxx_alignas)
285 #define	_Alignas(x)		alignas(x)
286 #else
287 /* XXX: Only emulates _Alignas(constant-expression); not _Alignas(type-name). */
288 #define	_Alignas(x)		__aligned(x)
289 #endif
290 #endif
291 
292 #if defined(__cplusplus) && __cplusplus >= 201103L
293 #define	_Alignof(x)		alignof(x)
294 #else
295 #define	_Alignof(x)		__alignof(x)
296 #endif
297 
298 #if !__has_extension(c_atomic) && !__has_extension(cxx_atomic)
299 /*
300  * No native support for _Atomic(). Place object in structure to prevent
301  * most forms of direct non-atomic access.
302  */
303 #define	_Atomic(T)		struct { T volatile __val; }
304 #endif
305 
306 #if defined(__cplusplus) && __cplusplus >= 201103L
307 #define	_Noreturn		[[noreturn]]
308 #else
309 #define	_Noreturn		__dead2
310 #endif
311 
312 #if !__has_extension(c_static_assert)
313 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
314     __has_extension(cxx_static_assert)
315 #define	_Static_assert(x, y)	static_assert(x, y)
316 #elif __GNUC_PREREQ__(4,6)
317 /* Nothing, gcc 4.6 and higher has _Static_assert built-in */
318 #elif defined(__COUNTER__)
319 #define	_Static_assert(x, y)	__Static_assert(x, __COUNTER__)
320 #define	__Static_assert(x, y)	___Static_assert(x, y)
321 #define	___Static_assert(x, y)	typedef char __assert_ ## y[(x) ? 1 : -1] \
322 				__unused
323 #else
324 #define	_Static_assert(x, y)	struct __hack
325 #endif
326 #endif
327 
328 #if !__has_extension(c_thread_local)
329 /*
330  * XXX: Some compilers (Clang 3.3, GCC 4.7) falsely announce C++11 mode
331  * without actually supporting the thread_local keyword. Don't check for
332  * the presence of C++11 when defining _Thread_local.
333  */
334 #if /* (defined(__cplusplus) && __cplusplus >= 201103L) || */ \
335     __has_extension(cxx_thread_local)
336 #define	_Thread_local		thread_local
337 #else
338 #define	_Thread_local		__thread
339 #endif
340 #endif
341 
342 #endif /* __STDC_VERSION__ || __STDC_VERSION__ < 201112L */
343 
344 /*
345  * Emulation of C11 _Generic().  Unlike the previously defined C11
346  * keywords, it is not possible to implement this using exactly the same
347  * syntax.  Therefore implement something similar under the name
348  * __generic().  Unlike _Generic(), this macro can only distinguish
349  * between a single type, so it requires nested invocations to
350  * distinguish multiple cases.
351  */
352 
353 #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) || \
354     __has_extension(c_generic_selections)
355 #define	__generic(expr, t, yes, no)					\
356 	_Generic(expr, t: yes, default: no)
357 #elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus)
358 #define	__generic(expr, t, yes, no)					\
359 	__builtin_choose_expr(						\
360 	    __builtin_types_compatible_p(__typeof(expr), t), yes, no)
361 #endif
362 
363 #if __GNUC_PREREQ__(2, 96)
364 #define	__malloc_like	__attribute__((__malloc__))
365 #define	__pure		__attribute__((__pure__))
366 #else
367 #define	__malloc_like
368 #define	__pure
369 #endif
370 
371 #if __GNUC_PREREQ__(3, 1) || (defined(__INTEL_COMPILER) && __INTEL_COMPILER >= 800)
372 #define	__always_inline	__attribute__((__always_inline__))
373 #else
374 #define	__always_inline
375 #endif
376 
377 #if __GNUC_PREREQ__(3, 1)
378 #define	__noinline	__attribute__ ((__noinline__))
379 #else
380 #define	__noinline
381 #endif
382 
383 #if __GNUC_PREREQ__(3, 3)
384 #define	__nonnull(x)	__attribute__((__nonnull__(x)))
385 #define	__nonnull_all	__attribute__((__nonnull__))
386 #else
387 #define	__nonnull(x)
388 #define	__nonnull_all
389 #endif
390 
391 #if __GNUC_PREREQ__(3, 4)
392 #define	__fastcall	__attribute__((__fastcall__))
393 #define	__result_use_check	__attribute__((__warn_unused_result__))
394 #else
395 #define	__fastcall
396 #define	__result_use_check
397 #endif
398 
399 #if __GNUC_PREREQ__(4, 1)
400 #define	__returns_twice	__attribute__((__returns_twice__))
401 #else
402 #define	__returns_twice
403 #endif
404 
405 #if __GNUC_PREREQ__(4, 6) || __has_builtin(__builtin_unreachable)
406 #define	__unreachable()	__builtin_unreachable()
407 #else
408 #define	__unreachable()	((void)0)
409 #endif
410 
411 /* XXX: should use `#if __STDC_VERSION__ < 199901'. */
412 #if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER)
413 #define	__func__	NULL
414 #endif
415 
416 /*
417  * GCC 2.95 provides `__restrict' as an extension to C90 to support the
418  * C99-specific `restrict' type qualifier.  We happen to use `__restrict' as
419  * a way to define the `restrict' type qualifier without disturbing older
420  * software that is unaware of C99 keywords.
421  */
422 #if !(__GNUC__ == 2 && __GNUC_MINOR__ == 95)
423 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 199901 || defined(lint)
424 #define	__restrict
425 #else
426 #define	__restrict	restrict
427 #endif
428 #endif
429 
430 /*
431  * GNU C version 2.96 adds explicit branch prediction so that
432  * the CPU back-end can hint the processor and also so that
433  * code blocks can be reordered such that the predicted path
434  * sees a more linear flow, thus improving cache behavior, etc.
435  *
436  * The following two macros provide us with a way to utilize this
437  * compiler feature.  Use __predict_true() if you expect the expression
438  * to evaluate to true, and __predict_false() if you expect the
439  * expression to evaluate to false.
440  *
441  * A few notes about usage:
442  *
443  *	* Generally, __predict_false() error condition checks (unless
444  *	  you have some _strong_ reason to do otherwise, in which case
445  *	  document it), and/or __predict_true() `no-error' condition
446  *	  checks, assuming you want to optimize for the no-error case.
447  *
448  *	* Other than that, if you don't know the likelihood of a test
449  *	  succeeding from empirical or other `hard' evidence, don't
450  *	  make predictions.
451  *
452  *	* These are meant to be used in places that are run `a lot'.
453  *	  It is wasteful to make predictions in code that is run
454  *	  seldomly (e.g. at subsystem initialization time) as the
455  *	  basic block reordering that this affects can often generate
456  *	  larger code.
457  */
458 #if __GNUC_PREREQ__(2, 96)
459 #define	__predict_true(exp)     __builtin_expect((exp), 1)
460 #define	__predict_false(exp)    __builtin_expect((exp), 0)
461 #else
462 #define	__predict_true(exp)     (exp)
463 #define	__predict_false(exp)    (exp)
464 #endif
465 
466 #if __GNUC_PREREQ__(4, 0)
467 #define	__sentinel	__attribute__((__sentinel__))
468 #define	__exported	__attribute__((__visibility__("default")))
469 #define	__hidden	__attribute__((__visibility__("hidden")))
470 #else
471 #define	__sentinel
472 #define	__exported
473 #define	__hidden
474 #endif
475 
476 #define __offsetof(type, field)	offsetof(type, field)
477 #define	__rangeof(type, start, end) \
478 	(__offsetof(type, end) - __offsetof(type, start))
479 
480 /*
481  * Given the pointer x to the member m of the struct s, return
482  * a pointer to the containing structure.  When using GCC, we first
483  * assign pointer x to a local variable, to check that its type is
484  * compatible with member m.
485  */
486 #if __GNUC_PREREQ__(3, 1)
487 #define	__containerof(x, s, m) ({					\
488 	const volatile __typeof(((s *)0)->m) *__x = (x);		\
489 	__DEQUALIFY(s *, (const volatile char *)__x - __offsetof(s, m));\
490 })
491 #else
492 #define	__containerof(x, s, m)						\
493 	__DEQUALIFY(s *, (const volatile char *)(x) - __offsetof(s, m))
494 #endif
495 
496 /*
497  * Compiler-dependent macros to declare that functions take printf-like
498  * or scanf-like arguments.  They are null except for versions of gcc
499  * that are known to support the features properly (old versions of gcc-2
500  * didn't permit keeping the keywords out of the application namespace).
501  */
502 #if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER)
503 #define	__printflike(fmtarg, firstvararg)
504 #define	__scanflike(fmtarg, firstvararg)
505 #define	__format_arg(fmtarg)
506 #define	__strfmonlike(fmtarg, firstvararg)
507 #define	__strftimelike(fmtarg, firstvararg)
508 #else
509 #define	__printflike(fmtarg, firstvararg) \
510 	    __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
511 #define	__scanflike(fmtarg, firstvararg) \
512 	    __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
513 #define	__format_arg(fmtarg)	__attribute__((__format_arg__ (fmtarg)))
514 #define	__strfmonlike(fmtarg, firstvararg) \
515 	    __attribute__((__format__ (__strfmon__, fmtarg, firstvararg)))
516 #define	__strftimelike(fmtarg, firstvararg) \
517 	    __attribute__((__format__ (__strftime__, fmtarg, firstvararg)))
518 #endif
519 
520 /*
521  * FORTIFY_SOURCE, and perhaps other compiler-specific features, require
522  * the use of non-standard inlining.  In general we should try to avoid
523  * using these but GCC-compatible compilers tend to support the extensions
524  * well enough to use them in limited cases.
525  */
526 #if defined(__GNUC_GNU_INLINE__) || defined(__GNUC_STDC_INLINE__)
527 #if __GNUC_PREREQ__(4, 3) || __has_attribute(__artificial__)
528 #define	__gnu_inline	__attribute__((__gnu_inline__, __artificial__))
529 #else
530 #define	__gnu_inline	__attribute__((__gnu_inline__))
531 #endif /* artificial */
532 #else
533 #define	__gnu_inline
534 #endif
535 
536 /* Compiler-dependent macros that rely on FreeBSD-specific extensions. */
537 #if defined(__FreeBSD_cc_version) && __FreeBSD_cc_version >= 300001 && \
538     defined(__GNUC__) && !defined(__INTEL_COMPILER)
539 #define	__printf0like(fmtarg, firstvararg) \
540 	    __attribute__((__format__ (__printf0__, fmtarg, firstvararg)))
541 #else
542 #define	__printf0like(fmtarg, firstvararg)
543 #endif
544 
545 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
546 #ifndef __INTEL_COMPILER
547 #define	__strong_reference(sym,aliassym)	\
548 	extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym)))
549 #endif
550 #ifdef __ELF__
551 #ifdef __STDC__
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 "\"");	\
558 	__asm__(".previous")
559 #define	__sym_compat(sym,impl,verid)	\
560 	__asm__(".symver " #impl ", " #sym "@" #verid)
561 #define	__sym_default(sym,impl,verid)	\
562 	__asm__(".symver " #impl ", " #sym "@@" #verid)
563 #else
564 #define	__weak_reference(sym,alias)	\
565 	__asm__(".weak alias");		\
566 	__asm__(".equ alias, sym")
567 #define	__warn_references(sym,msg)	\
568 	__asm__(".section .gnu.warning.sym"); \
569 	__asm__(".asciz \"msg\"");	\
570 	__asm__(".previous")
571 #define	__sym_compat(sym,impl,verid)	\
572 	__asm__(".symver impl, sym@verid")
573 #define	__sym_default(impl,sym,verid)	\
574 	__asm__(".symver impl, sym@@verid")
575 #endif	/* __STDC__ */
576 #else	/* !__ELF__ */
577 #ifdef __STDC__
578 #define	__weak_reference(sym,alias)	\
579 	__asm__(".stabs \"_" #alias "\",11,0,0,0");	\
580 	__asm__(".stabs \"_" #sym "\",1,0,0,0")
581 #define	__warn_references(sym,msg)	\
582 	__asm__(".stabs \"" msg "\",30,0,0,0");		\
583 	__asm__(".stabs \"_" #sym "\",1,0,0,0")
584 #else
585 #define	__weak_reference(sym,alias)	\
586 	__asm__(".stabs \"_/**/alias\",11,0,0,0");	\
587 	__asm__(".stabs \"_/**/sym\",1,0,0,0")
588 #define	__warn_references(sym,msg)	\
589 	__asm__(".stabs msg,30,0,0,0");			\
590 	__asm__(".stabs \"_/**/sym\",1,0,0,0")
591 #endif	/* __STDC__ */
592 #endif	/* __ELF__ */
593 #endif	/* __GNUC__ || __INTEL_COMPILER */
594 
595 #ifndef	__FBSDID
596 #define	__FBSDID(s)	struct __hack
597 #endif
598 
599 #ifndef	__RCSID
600 #define	__RCSID(s)	struct __hack
601 #endif
602 
603 #ifndef	__RCSID_SOURCE
604 #define	__RCSID_SOURCE(s)	struct __hack
605 #endif
606 
607 #ifndef	__SCCSID
608 #define	__SCCSID(s)	struct __hack
609 #endif
610 
611 #ifndef	__COPYRIGHT
612 #define	__COPYRIGHT(s)	struct __hack
613 #endif
614 
615 #ifndef	__DECONST
616 #define	__DECONST(type, var)	((type)(__uintptr_t)(const void *)(var))
617 #endif
618 
619 #ifndef	__DEVOLATILE
620 #define	__DEVOLATILE(type, var)	((type)(__uintptr_t)(volatile void *)(var))
621 #endif
622 
623 #ifndef	__DEQUALIFY
624 #define	__DEQUALIFY(type, var)	((type)(__uintptr_t)(const volatile void *)(var))
625 #endif
626 
627 /*
628  * Type Safety Checking
629  *
630  * Clang provides additional attributes to enable checking type safety
631  * properties that cannot be enforced by the C type system.
632  */
633 
634 #if __has_attribute(__argument_with_type_tag__) && \
635     __has_attribute(__type_tag_for_datatype__) && !defined(lint)
636 #define	__arg_type_tag(arg_kind, arg_idx, type_tag_idx) \
637 	    __attribute__((__argument_with_type_tag__(arg_kind, arg_idx, type_tag_idx)))
638 #define	__datatype_type_tag(kind, type) \
639 	    __attribute__((__type_tag_for_datatype__(kind, type)))
640 #else
641 #define	__arg_type_tag(arg_kind, arg_idx, type_tag_idx)
642 #define	__datatype_type_tag(kind, type)
643 #endif
644 
645 /*
646  * Lock annotations.
647  *
648  * Clang provides support for doing basic thread-safety tests at
649  * compile-time, by marking which locks will/should be held when
650  * entering/leaving a functions.
651  *
652  * Furthermore, it is also possible to annotate variables and structure
653  * members to enforce that they are only accessed when certain locks are
654  * held.
655  */
656 
657 #if __has_extension(c_thread_safety_attributes)
658 #define	__lock_annotate(x)	__attribute__((x))
659 #else
660 #define	__lock_annotate(x)
661 #endif
662 
663 /* Structure implements a lock. */
664 #define	__lockable		__lock_annotate(lockable)
665 
666 /* Function acquires an exclusive or shared lock. */
667 #define	__locks_exclusive(...) \
668 	__lock_annotate(exclusive_lock_function(__VA_ARGS__))
669 #define	__locks_shared(...) \
670 	__lock_annotate(shared_lock_function(__VA_ARGS__))
671 
672 /* Function attempts to acquire an exclusive or shared lock. */
673 #define	__trylocks_exclusive(...) \
674 	__lock_annotate(exclusive_trylock_function(__VA_ARGS__))
675 #define	__trylocks_shared(...) \
676 	__lock_annotate(shared_trylock_function(__VA_ARGS__))
677 
678 /* Function releases a lock. */
679 #define	__unlocks(...)		__lock_annotate(unlock_function(__VA_ARGS__))
680 
681 /* Function asserts that an exclusive or shared lock is held. */
682 #define	__asserts_exclusive(...) \
683 	__lock_annotate(assert_exclusive_lock(__VA_ARGS__))
684 #define	__asserts_shared(...) \
685 	__lock_annotate(assert_shared_lock(__VA_ARGS__))
686 
687 /* Function requires that an exclusive or shared lock is or is not held. */
688 #define	__requires_exclusive(...) \
689 	__lock_annotate(exclusive_locks_required(__VA_ARGS__))
690 #define	__requires_shared(...) \
691 	__lock_annotate(shared_locks_required(__VA_ARGS__))
692 #define	__requires_unlocked(...) \
693 	__lock_annotate(locks_excluded(__VA_ARGS__))
694 
695 /* Function should not be analyzed. */
696 #define	__no_lock_analysis	__lock_annotate(no_thread_safety_analysis)
697 
698 /* Guard variables and structure members by lock. */
699 #define	__guarded_by(x)		__lock_annotate(guarded_by(x))
700 #define	__pt_guarded_by(x)	__lock_annotate(pt_guarded_by(x))
701 
702 #endif /* !_SYS_CDEFS_H_ */
703