xref: /illumos-gate/usr/src/boot/sys/sys/cdefs.h (revision 59c22e7a)
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 #define	__alloc_size2(n, x)	__attribute__((__alloc_size__(n, x)))
243 #else
244 #define	__alloc_size(x)
245 #define	__alloc_size2(n, x)
246 #endif
247 #if __GNUC_PREREQ__(4, 9) || __has_attribute(__alloc_align__)
248 #define	__alloc_align(x)	__attribute__((__alloc_align__(x)))
249 #else
250 #define	__alloc_align(x)
251 #endif
252 #endif /* lint */
253 
254 #if !__GNUC_PREREQ__(2, 95)
255 #define	__alignof(x)	__offsetof(struct { char __a; x __b; }, __b)
256 #endif
257 
258 /*
259  * Keywords added in C11.
260  */
261 
262 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L || defined(lint)
263 
264 #if !__has_extension(c_alignas)
265 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
266     __has_extension(cxx_alignas)
267 #define	_Alignas(x)		alignas(x)
268 #else
269 /* XXX: Only emulates _Alignas(constant-expression); not _Alignas(type-name). */
270 #define	_Alignas(x)		__aligned(x)
271 #endif
272 #endif
273 
274 #if defined(__cplusplus) && __cplusplus >= 201103L
275 #define	_Alignof(x)		alignof(x)
276 #else
277 #define	_Alignof(x)		__alignof(x)
278 #endif
279 
280 #if !__has_extension(c_atomic) && !__has_extension(cxx_atomic)
281 /*
282  * No native support for _Atomic(). Place object in structure to prevent
283  * most forms of direct non-atomic access.
284  */
285 #define	_Atomic(T)		struct { T volatile __val; }
286 #endif
287 
288 #if defined(__cplusplus) && __cplusplus >= 201103L
289 #define	_Noreturn		[[noreturn]]
290 #else
291 #define	_Noreturn		__dead2
292 #endif
293 
294 #if !__has_extension(c_static_assert)
295 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \
296     __has_extension(cxx_static_assert)
297 #define	_Static_assert(x, y)	static_assert(x, y)
298 #elif __GNUC_PREREQ__(4,6)
299 /* Nothing, gcc 4.6 and higher has _Static_assert built-in */
300 #elif defined(__COUNTER__)
301 #define	_Static_assert(x, y)	__Static_assert(x, __COUNTER__)
302 #define	__Static_assert(x, y)	___Static_assert(x, y)
303 #define	___Static_assert(x, y)	typedef char __assert_ ## y[(x) ? 1 : -1] \
304 				__unused
305 #else
306 #define	_Static_assert(x, y)	struct __hack
307 #endif
308 #endif
309 
310 #if !__has_extension(c_thread_local)
311 /*
312  * XXX: Some compilers (Clang 3.3, GCC 4.7) falsely announce C++11 mode
313  * without actually supporting the thread_local keyword. Don't check for
314  * the presence of C++11 when defining _Thread_local.
315  */
316 #if /* (defined(__cplusplus) && __cplusplus >= 201103L) || */ \
317     __has_extension(cxx_thread_local)
318 #define	_Thread_local		thread_local
319 #else
320 #define	_Thread_local		__thread
321 #endif
322 #endif
323 
324 #endif /* __STDC_VERSION__ || __STDC_VERSION__ < 201112L */
325 
326 /*
327  * Emulation of C11 _Generic().  Unlike the previously defined C11
328  * keywords, it is not possible to implement this using exactly the same
329  * syntax.  Therefore implement something similar under the name
330  * __generic().  Unlike _Generic(), this macro can only distinguish
331  * between a single type, so it requires nested invocations to
332  * distinguish multiple cases.
333  */
334 
335 #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) || \
336     __has_extension(c_generic_selections)
337 #define	__generic(expr, t, yes, no)					\
338 	_Generic(expr, t: yes, default: no)
339 #elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus)
340 #define	__generic(expr, t, yes, no)					\
341 	__builtin_choose_expr(						\
342 	    __builtin_types_compatible_p(__typeof(expr), t), yes, no)
343 #endif
344 
345 #if __GNUC_PREREQ__(2, 96)
346 #define	__malloc_like	__attribute__((__malloc__))
347 #define	__pure		__attribute__((__pure__))
348 #else
349 #define	__malloc_like
350 #define	__pure
351 #endif
352 
353 #if __GNUC_PREREQ__(3, 1) || (defined(__INTEL_COMPILER) && __INTEL_COMPILER >= 800)
354 #define	__always_inline	__attribute__((__always_inline__))
355 #else
356 #define	__always_inline
357 #endif
358 
359 #if __GNUC_PREREQ__(3, 1)
360 #define	__noinline	__attribute__ ((__noinline__))
361 #else
362 #define	__noinline
363 #endif
364 
365 #if __GNUC_PREREQ__(3, 3)
366 #define	__nonnull(x)	__attribute__((__nonnull__(x)))
367 #define	__nonnull_all	__attribute__((__nonnull__))
368 #else
369 #define	__nonnull(x)
370 #define	__nonnull_all
371 #endif
372 
373 #if __GNUC_PREREQ__(3, 4)
374 #define	__fastcall	__attribute__((__fastcall__))
375 #define	__result_use_check	__attribute__((__warn_unused_result__))
376 #else
377 #define	__fastcall
378 #define	__result_use_check
379 #endif
380 
381 #if __GNUC_PREREQ__(4, 1)
382 #define	__returns_twice	__attribute__((__returns_twice__))
383 #else
384 #define	__returns_twice
385 #endif
386 
387 #if __GNUC_PREREQ__(4, 6) || __has_builtin(__builtin_unreachable)
388 #define	__unreachable()	__builtin_unreachable()
389 #else
390 #define	__unreachable()	((void)0)
391 #endif
392 
393 /* XXX: should use `#if __STDC_VERSION__ < 199901'. */
394 #if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER)
395 #define	__func__	NULL
396 #endif
397 
398 #if (defined(__INTEL_COMPILER) || (defined(__GNUC__) && __GNUC__ >= 2)) && !defined(__STRICT_ANSI__) || __STDC_VERSION__ >= 199901
399 #define	__LONG_LONG_SUPPORTED
400 #endif
401 
402 /* C++11 exposes a load of C99 stuff */
403 #if defined(__cplusplus) && __cplusplus >= 201103L
404 #define	__LONG_LONG_SUPPORTED
405 #ifndef	__STDC_LIMIT_MACROS
406 #define	__STDC_LIMIT_MACROS
407 #endif
408 #ifndef	__STDC_CONSTANT_MACROS
409 #define	__STDC_CONSTANT_MACROS
410 #endif
411 #endif
412 
413 /*
414  * GCC 2.95 provides `__restrict' as an extension to C90 to support the
415  * C99-specific `restrict' type qualifier.  We happen to use `__restrict' as
416  * a way to define the `restrict' type qualifier without disturbing older
417  * software that is unaware of C99 keywords.
418  */
419 #if !(__GNUC__ == 2 && __GNUC_MINOR__ == 95)
420 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 199901 || defined(lint)
421 #define	__restrict
422 #else
423 #define	__restrict	restrict
424 #endif
425 #endif
426 
427 /*
428  * GNU C version 2.96 adds explicit branch prediction so that
429  * the CPU back-end can hint the processor and also so that
430  * code blocks can be reordered such that the predicted path
431  * sees a more linear flow, thus improving cache behavior, etc.
432  *
433  * The following two macros provide us with a way to utilize this
434  * compiler feature.  Use __predict_true() if you expect the expression
435  * to evaluate to true, and __predict_false() if you expect the
436  * expression to evaluate to false.
437  *
438  * A few notes about usage:
439  *
440  *	* Generally, __predict_false() error condition checks (unless
441  *	  you have some _strong_ reason to do otherwise, in which case
442  *	  document it), and/or __predict_true() `no-error' condition
443  *	  checks, assuming you want to optimize for the no-error case.
444  *
445  *	* Other than that, if you don't know the likelihood of a test
446  *	  succeeding from empirical or other `hard' evidence, don't
447  *	  make predictions.
448  *
449  *	* These are meant to be used in places that are run `a lot'.
450  *	  It is wasteful to make predictions in code that is run
451  *	  seldomly (e.g. at subsystem initialization time) as the
452  *	  basic block reordering that this affects can often generate
453  *	  larger code.
454  */
455 #if __GNUC_PREREQ__(2, 96)
456 #define	__predict_true(exp)     __builtin_expect((exp), 1)
457 #define	__predict_false(exp)    __builtin_expect((exp), 0)
458 #else
459 #define	__predict_true(exp)     (exp)
460 #define	__predict_false(exp)    (exp)
461 #endif
462 
463 #if __GNUC_PREREQ__(4, 0)
464 #define	__null_sentinel	__attribute__((__sentinel__))
465 #define	__exported	__attribute__((__visibility__("default")))
466 #define	__hidden	__attribute__((__visibility__("hidden")))
467 #else
468 #define	__null_sentinel
469 #define	__exported
470 #define	__hidden
471 #endif
472 
473 /*
474  * We define this here since <stddef.h>, <sys/queue.h>, and <sys/types.h>
475  * require it.
476  */
477 #if __GNUC_PREREQ__(4, 1)
478 #define	__offsetof(type, field)	 __builtin_offsetof(type, field)
479 #else
480 #ifndef __cplusplus
481 #define	__offsetof(type, field) \
482 	((__size_t)(__uintptr_t)((const volatile void *)&((type *)0)->field))
483 #else
484 #define	__offsetof(type, field)					\
485   (__offsetof__ (reinterpret_cast <__size_t>			\
486                  (&reinterpret_cast <const volatile char &>	\
487                   (static_cast<type *> (0)->field))))
488 #endif
489 #endif
490 #define	__rangeof(type, start, end) \
491 	(__offsetof(type, end) - __offsetof(type, start))
492 
493 /*
494  * Given the pointer x to the member m of the struct s, return
495  * a pointer to the containing structure.  When using GCC, we first
496  * assign pointer x to a local variable, to check that its type is
497  * compatible with member m.
498  */
499 #if __GNUC_PREREQ__(3, 1)
500 #define	__containerof(x, s, m) ({					\
501 	const volatile __typeof(((s *)0)->m) *__x = (x);		\
502 	__DEQUALIFY(s *, (const volatile char *)__x - __offsetof(s, m));\
503 })
504 #else
505 #define	__containerof(x, s, m)						\
506 	__DEQUALIFY(s *, (const volatile char *)(x) - __offsetof(s, m))
507 #endif
508 
509 /*
510  * Compiler-dependent macros to declare that functions take printf-like
511  * or scanf-like arguments.  They are null except for versions of gcc
512  * that are known to support the features properly (old versions of gcc-2
513  * didn't permit keeping the keywords out of the application namespace).
514  */
515 #if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER)
516 #define	__printflike(fmtarg, firstvararg)
517 #define	__scanflike(fmtarg, firstvararg)
518 #define	__format_arg(fmtarg)
519 #define	__strfmonlike(fmtarg, firstvararg)
520 #define	__strftimelike(fmtarg, firstvararg)
521 #else
522 #define	__printflike(fmtarg, firstvararg) \
523 	    __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
524 #define	__scanflike(fmtarg, firstvararg) \
525 	    __attribute__((__format__ (__scanf__, fmtarg, firstvararg)))
526 #define	__format_arg(fmtarg)	__attribute__((__format_arg__ (fmtarg)))
527 #define	__strfmonlike(fmtarg, firstvararg) \
528 	    __attribute__((__format__ (__strfmon__, fmtarg, firstvararg)))
529 #define	__strftimelike(fmtarg, firstvararg) \
530 	    __attribute__((__format__ (__strftime__, fmtarg, firstvararg)))
531 #endif
532 
533 /*
534  * FORTIFY_SOURCE, and perhaps other compiler-specific features, require
535  * the use of non-standard inlining.  In general we should try to avoid
536  * using these but GCC-compatible compilers tend to support the extensions
537  * well enough to use them in limited cases.
538  */
539 #if defined(__GNUC_GNU_INLINE__) || defined(__GNUC_STDC_INLINE__)
540 #if __GNUC_PREREQ__(4, 3) || __has_attribute(__artificial__)
541 #define	__gnu_inline	__attribute__((__gnu_inline__, __artificial__))
542 #else
543 #define	__gnu_inline	__attribute__((__gnu_inline__))
544 #endif /* artificial */
545 #else
546 #define	__gnu_inline
547 #endif
548 
549 /* Compiler-dependent macros that rely on FreeBSD-specific extensions. */
550 #if defined(__FreeBSD_cc_version) && __FreeBSD_cc_version >= 300001 && \
551     defined(__GNUC__) && !defined(__INTEL_COMPILER)
552 #define	__printf0like(fmtarg, firstvararg) \
553 	    __attribute__((__format__ (__printf0__, fmtarg, firstvararg)))
554 #else
555 #define	__printf0like(fmtarg, firstvararg)
556 #endif
557 
558 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
559 #ifndef __INTEL_COMPILER
560 #define	__strong_reference(sym,aliassym)	\
561 	extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym)))
562 #endif
563 #ifdef __STDC__
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(sym,impl,verid)	\
574 	__asm__(".symver " #impl ", " #sym "@@" #verid)
575 #else
576 #define	__weak_reference(sym,alias)	\
577 	__asm__(".weak alias");		\
578 	__asm__(".equ alias, sym")
579 #define	__warn_references(sym,msg)	\
580 	__asm__(".section .gnu.warning.sym"); \
581 	__asm__(".asciz \"msg\"");	\
582 	__asm__(".previous")
583 #define	__sym_compat(sym,impl,verid)	\
584 	__asm__(".symver impl, sym@verid")
585 #define	__sym_default(impl,sym,verid)	\
586 	__asm__(".symver impl, sym@@verid")
587 #endif	/* __STDC__ */
588 #endif	/* __GNUC__ || __INTEL_COMPILER */
589 
590 #define	__GLOBL1(sym)	__asm__(".globl " #sym)
591 #define	__GLOBL(sym)	__GLOBL1(sym)
592 
593 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
594 #define	__IDSTRING(name,string)	__asm__(".ident\t\"" string "\"")
595 #else
596 /*
597  * The following definition might not work well if used in header files,
598  * but it should be better than nothing.  If you want a "do nothing"
599  * version, then it should generate some harmless declaration, such as:
600  *    #define	__IDSTRING(name,string)	struct __hack
601  */
602 #define	__IDSTRING(name,string)	static const char name[] __unused = string
603 #endif
604 
605 /*
606  * Embed the rcs id of a source file in the resulting library.  Note that in
607  * more recent ELF binutils, we use .ident allowing the ID to be stripped.
608  * Usage:
609  *	__FBSDID("$FreeBSD$");
610  */
611 #ifndef	__FBSDID
612 #if !defined(lint) && !defined(STRIP_FBSDID)
613 #define	__FBSDID(s)	__IDSTRING(__CONCAT(__rcsid_,__LINE__),s)
614 #else
615 #define	__FBSDID(s)	struct __hack
616 #endif
617 #endif
618 
619 #ifndef	__RCSID
620 #ifndef	NO__RCSID
621 #define	__RCSID(s)	__IDSTRING(__CONCAT(__rcsid_,__LINE__),s)
622 #else
623 #define	__RCSID(s)	struct __hack
624 #endif
625 #endif
626 
627 #ifndef	__RCSID_SOURCE
628 #ifndef	NO__RCSID_SOURCE
629 #define	__RCSID_SOURCE(s)	__IDSTRING(__CONCAT(__rcsid_source_,__LINE__),s)
630 #else
631 #define	__RCSID_SOURCE(s)	struct __hack
632 #endif
633 #endif
634 
635 #ifndef	__SCCSID
636 #ifndef	NO__SCCSID
637 #define	__SCCSID(s)	__IDSTRING(__CONCAT(__sccsid_,__LINE__),s)
638 #else
639 #define	__SCCSID(s)	struct __hack
640 #endif
641 #endif
642 
643 #ifndef	__COPYRIGHT
644 #ifndef	NO__COPYRIGHT
645 #define	__COPYRIGHT(s)	__IDSTRING(__CONCAT(__copyright_,__LINE__),s)
646 #else
647 #define	__COPYRIGHT(s)	struct __hack
648 #endif
649 #endif
650 
651 #ifndef	__DECONST
652 #define	__DECONST(type, var)	((type)(__uintptr_t)(const void *)(var))
653 #endif
654 
655 #ifndef	__DEVOLATILE
656 #define	__DEVOLATILE(type, var)	((type)(__uintptr_t)(volatile void *)(var))
657 #endif
658 
659 #ifndef	__DEQUALIFY
660 #define	__DEQUALIFY(type, var)	((type)(__uintptr_t)(const volatile void *)(var))
661 #endif
662 
663 /*-
664  * The following definitions are an extension of the behavior originally
665  * implemented in <sys/_posix.h>, but with a different level of granularity.
666  * POSIX.1 requires that the macros we test be defined before any standard
667  * header file is included.
668  *
669  * Here's a quick run-down of the versions:
670  *  defined(_POSIX_SOURCE)		1003.1-1988
671  *  _POSIX_C_SOURCE == 1		1003.1-1990
672  *  _POSIX_C_SOURCE == 2		1003.2-1992 C Language Binding Option
673  *  _POSIX_C_SOURCE == 199309		1003.1b-1993
674  *  _POSIX_C_SOURCE == 199506		1003.1c-1995, 1003.1i-1995,
675  *					and the omnibus ISO/IEC 9945-1: 1996
676  *  _POSIX_C_SOURCE == 200112		1003.1-2001
677  *  _POSIX_C_SOURCE == 200809		1003.1-2008
678  *
679  * In addition, the X/Open Portability Guide, which is now the Single UNIX
680  * Specification, defines a feature-test macro which indicates the version of
681  * that specification, and which subsumes _POSIX_C_SOURCE.
682  *
683  * Our macros begin with two underscores to avoid namespace screwage.
684  */
685 
686 /* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */
687 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 1
688 #undef _POSIX_C_SOURCE		/* Probably illegal, but beyond caring now. */
689 #define	_POSIX_C_SOURCE		199009
690 #endif
691 
692 /* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */
693 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 2
694 #undef _POSIX_C_SOURCE
695 #define	_POSIX_C_SOURCE		199209
696 #endif
697 
698 /* Deal with various X/Open Portability Guides and Single UNIX Spec. */
699 #ifdef _XOPEN_SOURCE
700 #if _XOPEN_SOURCE - 0 >= 700
701 #define	__XSI_VISIBLE		700
702 #undef _POSIX_C_SOURCE
703 #define	_POSIX_C_SOURCE		200809
704 #elif _XOPEN_SOURCE - 0 >= 600
705 #define	__XSI_VISIBLE		600
706 #undef _POSIX_C_SOURCE
707 #define	_POSIX_C_SOURCE		200112
708 #elif _XOPEN_SOURCE - 0 >= 500
709 #define	__XSI_VISIBLE		500
710 #undef _POSIX_C_SOURCE
711 #define	_POSIX_C_SOURCE		199506
712 #endif
713 #endif
714 
715 /*
716  * Deal with all versions of POSIX.  The ordering relative to the tests above is
717  * important.
718  */
719 #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE)
720 #define	_POSIX_C_SOURCE		198808
721 #endif
722 #ifdef _POSIX_C_SOURCE
723 #if _POSIX_C_SOURCE >= 200809
724 #define	__POSIX_VISIBLE		200809
725 #define	__ISO_C_VISIBLE		1999
726 #elif _POSIX_C_SOURCE >= 200112
727 #define	__POSIX_VISIBLE		200112
728 #define	__ISO_C_VISIBLE		1999
729 #elif _POSIX_C_SOURCE >= 199506
730 #define	__POSIX_VISIBLE		199506
731 #define	__ISO_C_VISIBLE		1990
732 #elif _POSIX_C_SOURCE >= 199309
733 #define	__POSIX_VISIBLE		199309
734 #define	__ISO_C_VISIBLE		1990
735 #elif _POSIX_C_SOURCE >= 199209
736 #define	__POSIX_VISIBLE		199209
737 #define	__ISO_C_VISIBLE		1990
738 #elif _POSIX_C_SOURCE >= 199009
739 #define	__POSIX_VISIBLE		199009
740 #define	__ISO_C_VISIBLE		1990
741 #else
742 #define	__POSIX_VISIBLE		198808
743 #define	__ISO_C_VISIBLE		0
744 #endif /* _POSIX_C_SOURCE */
745 #else
746 /*-
747  * Deal with _ANSI_SOURCE:
748  * If it is defined, and no other compilation environment is explicitly
749  * requested, then define our internal feature-test macros to zero.  This
750  * makes no difference to the preprocessor (undefined symbols in preprocessing
751  * expressions are defined to have value zero), but makes it more convenient for
752  * a test program to print out the values.
753  *
754  * If a program mistakenly defines _ANSI_SOURCE and some other macro such as
755  * _POSIX_C_SOURCE, we will assume that it wants the broader compilation
756  * environment (and in fact we will never get here).
757  */
758 #if defined(_ANSI_SOURCE)	/* Hide almost everything. */
759 #define	__POSIX_VISIBLE		0
760 #define	__XSI_VISIBLE		0
761 #define	__BSD_VISIBLE		0
762 #define	__ISO_C_VISIBLE		1990
763 #elif defined(_C99_SOURCE)	/* Localism to specify strict C99 env. */
764 #define	__POSIX_VISIBLE		0
765 #define	__XSI_VISIBLE		0
766 #define	__BSD_VISIBLE		0
767 #define	__ISO_C_VISIBLE		1999
768 #elif defined(_C11_SOURCE)	/* Localism to specify strict C11 env. */
769 #define	__POSIX_VISIBLE		0
770 #define	__XSI_VISIBLE		0
771 #define	__BSD_VISIBLE		0
772 #define	__ISO_C_VISIBLE		2011
773 #else				/* Default environment: show everything. */
774 #define	__POSIX_VISIBLE		200809
775 #define	__XSI_VISIBLE		700
776 #define	__BSD_VISIBLE		1
777 #define	__ISO_C_VISIBLE		2011
778 #endif
779 #endif
780 
781 #if defined(__mips) || defined(__powerpc64__) || defined(__riscv__)
782 #define	__NO_TLS 1
783 #endif
784 
785 /*
786  * Type Safety Checking
787  *
788  * Clang provides additional attributes to enable checking type safety
789  * properties that cannot be enforced by the C type system.
790  */
791 
792 #if __has_attribute(__argument_with_type_tag__) && \
793     __has_attribute(__type_tag_for_datatype__) && !defined(lint)
794 #define	__arg_type_tag(arg_kind, arg_idx, type_tag_idx) \
795 	    __attribute__((__argument_with_type_tag__(arg_kind, arg_idx, type_tag_idx)))
796 #define	__datatype_type_tag(kind, type) \
797 	    __attribute__((__type_tag_for_datatype__(kind, type)))
798 #else
799 #define	__arg_type_tag(arg_kind, arg_idx, type_tag_idx)
800 #define	__datatype_type_tag(kind, type)
801 #endif
802 
803 /*
804  * Lock annotations.
805  *
806  * Clang provides support for doing basic thread-safety tests at
807  * compile-time, by marking which locks will/should be held when
808  * entering/leaving a functions.
809  *
810  * Furthermore, it is also possible to annotate variables and structure
811  * members to enforce that they are only accessed when certain locks are
812  * held.
813  */
814 
815 #if __has_extension(c_thread_safety_attributes)
816 #define	__lock_annotate(x)	__attribute__((x))
817 #else
818 #define	__lock_annotate(x)
819 #endif
820 
821 /* Structure implements a lock. */
822 #define	__lockable		__lock_annotate(lockable)
823 
824 /* Function acquires an exclusive or shared lock. */
825 #define	__locks_exclusive(...) \
826 	__lock_annotate(exclusive_lock_function(__VA_ARGS__))
827 #define	__locks_shared(...) \
828 	__lock_annotate(shared_lock_function(__VA_ARGS__))
829 
830 /* Function attempts to acquire an exclusive or shared lock. */
831 #define	__trylocks_exclusive(...) \
832 	__lock_annotate(exclusive_trylock_function(__VA_ARGS__))
833 #define	__trylocks_shared(...) \
834 	__lock_annotate(shared_trylock_function(__VA_ARGS__))
835 
836 /* Function releases a lock. */
837 #define	__unlocks(...)		__lock_annotate(unlock_function(__VA_ARGS__))
838 
839 /* Function asserts that an exclusive or shared lock is held. */
840 #define	__asserts_exclusive(...) \
841 	__lock_annotate(assert_exclusive_lock(__VA_ARGS__))
842 #define	__asserts_shared(...) \
843 	__lock_annotate(assert_shared_lock(__VA_ARGS__))
844 
845 /* Function requires that an exclusive or shared lock is or is not held. */
846 #define	__requires_exclusive(...) \
847 	__lock_annotate(exclusive_locks_required(__VA_ARGS__))
848 #define	__requires_shared(...) \
849 	__lock_annotate(shared_locks_required(__VA_ARGS__))
850 #define	__requires_unlocked(...) \
851 	__lock_annotate(locks_excluded(__VA_ARGS__))
852 
853 /* Function should not be analyzed. */
854 #define	__no_lock_analysis	__lock_annotate(no_thread_safety_analysis)
855 
856 /* Guard variables and structure members by lock. */
857 #define	__guarded_by(x)		__lock_annotate(guarded_by(x))
858 #define	__pt_guarded_by(x)	__lock_annotate(pt_guarded_by(x))
859 
860 #endif /* !_SYS_CDEFS_H_ */
861