1 /* Copyright (C) 1992-2021 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <https://www.gnu.org/licenses/>. */
17
18 #ifndef _SYS_CDEFS_H
19 #define _SYS_CDEFS_H 1
20
21 /* We are almost always included from features.h. */
22 #ifndef _FEATURES_H
23 # include <features.h>
24 #endif
25
26 /* The GNU libc does not support any K&R compilers or the traditional mode
27 of ISO C compilers anymore. Check for some of the combinations not
28 supported anymore. */
29 #if defined __GNUC__ && !defined __STDC__
30 # error "You need a ISO C conforming compiler to use the glibc headers"
31 #endif
32
33 /* Some user header file might have defined this before. */
34 #undef __P
35 #undef __PMT
36
37 /* Compilers that lack __has_attribute may object to
38 #if defined __has_attribute && __has_attribute (...)
39 even though they do not need to evaluate the right-hand side of the &&.
40 Similarly for __has_builtin, etc. */
41 #if (defined __has_attribute \
42 && (!defined __clang_minor__ \
43 || 3 < __clang_major__ + (5 <= __clang_minor__)))
44 # define __glibc_has_attribute(attr) __has_attribute (attr)
45 #else
46 # define __glibc_has_attribute(attr) 0
47 #endif
48 #ifdef __has_builtin
49 # define __glibc_has_builtin(name) __has_builtin (name)
50 #else
51 # define __glibc_has_builtin(name) 0
52 #endif
53 #ifdef __has_extension
54 # define __glibc_has_extension(ext) __has_extension (ext)
55 #else
56 # define __glibc_has_extension(ext) 0
57 #endif
58
59 #if defined __GNUC__ || defined __clang__
60
61 /* All functions, except those with callbacks or those that
62 synchronize memory, are leaf functions. */
63 # if __GNUC_PREREQ (4, 6) && !defined _LIBC
64 # define __LEAF , __leaf__
65 # define __LEAF_ATTR __attribute__ ((__leaf__))
66 # else
67 # define __LEAF
68 # define __LEAF_ATTR
69 # endif
70
71 /* GCC can always grok prototypes. For C++ programs we add throw()
72 to help it optimize the function calls. But this only works with
73 gcc 2.8.x and egcs. For gcc 3.4 and up we even mark C functions
74 as non-throwing using a function attribute since programs can use
75 the -fexceptions options for C code as well. */
76 # if !defined __cplusplus \
77 && (__GNUC_PREREQ (3, 4) || __glibc_has_attribute (__nothrow__))
78 # define __THROW __attribute__ ((__nothrow__ __LEAF))
79 # define __THROWNL __attribute__ ((__nothrow__))
80 # define __NTH(fct) __attribute__ ((__nothrow__ __LEAF)) fct
81 # define __NTHNL(fct) __attribute__ ((__nothrow__)) fct
82 # else
83 # if defined __cplusplus && (__GNUC_PREREQ (2,8) || __clang_major >= 4)
84 # if __cplusplus >= 201103L
85 # define __THROW noexcept (true)
86 # else
87 # define __THROW throw ()
88 # endif
89 # define __THROWNL __THROW
90 # define __NTH(fct) __LEAF_ATTR fct __THROW
91 # define __NTHNL(fct) fct __THROW
92 # else
93 # define __THROW
94 # define __THROWNL
95 # define __NTH(fct) fct
96 # define __NTHNL(fct) fct
97 # endif
98 # endif
99
100 #else /* Not GCC or clang. */
101
102 # if (defined __cplusplus \
103 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L))
104 # define __inline inline
105 # else
106 # define __inline /* No inline functions. */
107 # endif
108
109 # define __THROW
110 # define __THROWNL
111 # define __NTH(fct) fct
112
113 #endif /* GCC || clang. */
114
115 /* These two macros are not used in glibc anymore. They are kept here
116 only because some other projects expect the macros to be defined. */
117 #define __P(args) args
118 #define __PMT(args) args
119
120 /* For these things, GCC behaves the ANSI way normally,
121 and the non-ANSI way under -traditional. */
122
123 #define __CONCAT(x,y) x ## y
124 #define __STRING(x) #x
125
126 /* This is not a typedef so `const __ptr_t' does the right thing. */
127 #define __ptr_t void *
128
129
130 /* C++ needs to know that types and declarations are C, not C++. */
131 #ifdef __cplusplus
132 # define __BEGIN_DECLS extern "C" {
133 # define __END_DECLS }
134 #else
135 # define __BEGIN_DECLS
136 # define __END_DECLS
137 #endif
138
139
140 /* Fortify support. */
141 #define __bos(ptr) __builtin_object_size (ptr, __USE_FORTIFY_LEVEL > 1)
142 #define __bos0(ptr) __builtin_object_size (ptr, 0)
143
144 /* Use __builtin_dynamic_object_size at _FORTIFY_SOURCE=3 when available. */
145 #if __USE_FORTIFY_LEVEL == 3 && __glibc_clang_prereq (9, 0)
146 # define __glibc_objsize0(__o) __builtin_dynamic_object_size (__o, 0)
147 # define __glibc_objsize(__o) __builtin_dynamic_object_size (__o, 1)
148 #else
149 # define __glibc_objsize0(__o) __bos0 (__o)
150 # define __glibc_objsize(__o) __bos (__o)
151 #endif
152
153 #if __GNUC_PREREQ (4,3)
154 # define __warnattr(msg) __attribute__((__warning__ (msg)))
155 # define __errordecl(name, msg) \
156 extern void name (void) __attribute__((__error__ (msg)))
157 #else
158 # define __warnattr(msg)
159 # define __errordecl(name, msg) extern void name (void)
160 #endif
161
162 /* Support for flexible arrays.
163 Headers that should use flexible arrays only if they're "real"
164 (e.g. only if they won't affect sizeof()) should test
165 #if __glibc_c99_flexarr_available. */
166 #if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L && !defined __HP_cc
167 # define __flexarr []
168 # define __glibc_c99_flexarr_available 1
169 #elif __GNUC_PREREQ (2,97) || defined __clang__
170 /* GCC 2.97 and clang support C99 flexible array members as an extension,
171 even when in C89 mode or compiling C++ (any version). */
172 # define __flexarr []
173 # define __glibc_c99_flexarr_available 1
174 #elif defined __GNUC__
175 /* Pre-2.97 GCC did not support C99 flexible arrays but did have
176 an equivalent extension with slightly different notation. */
177 # define __flexarr [0]
178 # define __glibc_c99_flexarr_available 1
179 #else
180 /* Some other non-C99 compiler. Approximate with [1]. */
181 # define __flexarr [1]
182 # define __glibc_c99_flexarr_available 0
183 #endif
184
185
186 /* __asm__ ("xyz") is used throughout the headers to rename functions
187 at the assembly language level. This is wrapped by the __REDIRECT
188 macro, in order to support compilers that can do this some other
189 way. When compilers don't support asm-names at all, we have to do
190 preprocessor tricks instead (which don't have exactly the right
191 semantics, but it's the best we can do).
192
193 Example:
194 int __REDIRECT(setpgrp, (__pid_t pid, __pid_t pgrp), setpgid); */
195
196 #if (defined __GNUC__ && __GNUC__ >= 2) || (__clang_major__ >= 4)
197
198 # define __REDIRECT(name, proto, alias) name proto __asm__ (__ASMNAME (#alias))
199 # ifdef __cplusplus
200 # define __REDIRECT_NTH(name, proto, alias) \
201 name proto __THROW __asm__ (__ASMNAME (#alias))
202 # define __REDIRECT_NTHNL(name, proto, alias) \
203 name proto __THROWNL __asm__ (__ASMNAME (#alias))
204 # else
205 # define __REDIRECT_NTH(name, proto, alias) \
206 name proto __asm__ (__ASMNAME (#alias)) __THROW
207 # define __REDIRECT_NTHNL(name, proto, alias) \
208 name proto __asm__ (__ASMNAME (#alias)) __THROWNL
209 # endif
210 # define __ASMNAME(cname) __ASMNAME2 (__USER_LABEL_PREFIX__, cname)
211 # define __ASMNAME2(prefix, cname) __STRING (prefix) cname
212
213 /*
214 #elif __SOME_OTHER_COMPILER__
215
216 # define __REDIRECT(name, proto, alias) name proto; \
217 _Pragma("let " #name " = " #alias)
218 */
219 #endif
220
221 /* GCC and clang have various useful declarations that can be made with
222 the '__attribute__' syntax. All of the ways we use this do fine if
223 they are omitted for compilers that don't understand it. */
224 #if !(defined __GNUC__ || defined __clang__)
225 # define __attribute__(xyz) /* Ignore */
226 #endif
227
228 /* At some point during the gcc 2.96 development the `malloc' attribute
229 for functions was introduced. We don't want to use it unconditionally
230 (although this would be possible) since it generates warnings. */
231 #if __GNUC_PREREQ (2,96) || __glibc_has_attribute (__malloc__)
232 # define __attribute_malloc__ __attribute__ ((__malloc__))
233 #else
234 # define __attribute_malloc__ /* Ignore */
235 #endif
236
237 /* Tell the compiler which arguments to an allocation function
238 indicate the size of the allocation. */
239 #if __GNUC_PREREQ (4, 3)
240 # define __attribute_alloc_size__(params) \
241 __attribute__ ((__alloc_size__ params))
242 #else
243 # define __attribute_alloc_size__(params) /* Ignore. */
244 #endif
245
246 /* At some point during the gcc 2.96 development the `pure' attribute
247 for functions was introduced. We don't want to use it unconditionally
248 (although this would be possible) since it generates warnings. */
249 #if __GNUC_PREREQ (2,96) || __glibc_has_attribute (__pure__)
250 # define __attribute_pure__ __attribute__ ((__pure__))
251 #else
252 # define __attribute_pure__ /* Ignore */
253 #endif
254
255 /* This declaration tells the compiler that the value is constant. */
256 #if __GNUC_PREREQ (2,5) || __glibc_has_attribute (__const__)
257 # define __attribute_const__ __attribute__ ((__const__))
258 #else
259 # define __attribute_const__ /* Ignore */
260 #endif
261
262 #if __GNUC_PREREQ (2,7) || __glibc_has_attribute (__unused__)
263 # define __attribute_maybe_unused__ __attribute__ ((__unused__))
264 #else
265 # define __attribute_maybe_unused__ /* Ignore */
266 #endif
267
268 /* At some point during the gcc 3.1 development the `used' attribute
269 for functions was introduced. We don't want to use it unconditionally
270 (although this would be possible) since it generates warnings. */
271 #if __GNUC_PREREQ (3,1) || __glibc_has_attribute (__used__)
272 # define __attribute_used__ __attribute__ ((__used__))
273 # define __attribute_noinline__ __attribute__ ((__noinline__))
274 #else
275 # define __attribute_used__ __attribute__ ((__unused__))
276 # define __attribute_noinline__ /* Ignore */
277 #endif
278
279 /* Since version 3.2, gcc allows marking deprecated functions. */
280 #if __GNUC_PREREQ (3,2) || __glibc_has_attribute (__deprecated__)
281 # define __attribute_deprecated__ __attribute__ ((__deprecated__))
282 #else
283 # define __attribute_deprecated__ /* Ignore */
284 #endif
285
286 /* Since version 4.5, gcc also allows one to specify the message printed
287 when a deprecated function is used. clang claims to be gcc 4.2, but
288 may also support this feature. */
289 #if __GNUC_PREREQ (4,5) \
290 || __glibc_has_extension (__attribute_deprecated_with_message__)
291 # define __attribute_deprecated_msg__(msg) \
292 __attribute__ ((__deprecated__ (msg)))
293 #else
294 # define __attribute_deprecated_msg__(msg) __attribute_deprecated__
295 #endif
296
297 /* At some point during the gcc 2.8 development the `format_arg' attribute
298 for functions was introduced. We don't want to use it unconditionally
299 (although this would be possible) since it generates warnings.
300 If several `format_arg' attributes are given for the same function, in
301 gcc-3.0 and older, all but the last one are ignored. In newer gccs,
302 all designated arguments are considered. */
303 #if __GNUC_PREREQ (2,8) || __glibc_has_attribute (__format_arg__)
304 # define __attribute_format_arg__(x) __attribute__ ((__format_arg__ (x)))
305 #else
306 # define __attribute_format_arg__(x) /* Ignore */
307 #endif
308
309 /* At some point during the gcc 2.97 development the `strfmon' format
310 attribute for functions was introduced. We don't want to use it
311 unconditionally (although this would be possible) since it
312 generates warnings. */
313 #if __GNUC_PREREQ (2,97) || __glibc_has_attribute (__format__)
314 # define __attribute_format_strfmon__(a,b) \
315 __attribute__ ((__format__ (__strfmon__, a, b)))
316 #else
317 # define __attribute_format_strfmon__(a,b) /* Ignore */
318 #endif
319
320 /* The nonnull function attribute marks pointer parameters that
321 must not be NULL. This has the name __nonnull in glibc,
322 and __attribute_nonnull__ in files shared with Gnulib to avoid
323 collision with a different __nonnull in DragonFlyBSD 5.9. */
324 #ifndef __attribute_nonnull__
325 # if __GNUC_PREREQ (3,3) || __glibc_has_attribute (__nonnull__)
326 # define __attribute_nonnull__(params) __attribute__ ((__nonnull__ params))
327 # else
328 # define __attribute_nonnull__(params)
329 # endif
330 #endif
331 #ifndef __nonnull
332 # define __nonnull(params) __attribute_nonnull__ (params)
333 #endif
334
335 /* The returns_nonnull function attribute marks the return type of the function
336 as always being non-null. */
337 #ifndef __returns_nonnull
338 # if __GNUC_PREREQ (4, 9) || __glibc_has_attribute (__returns_nonnull__)
339 # define __returns_nonnull __attribute__ ((__returns_nonnull__))
340 # else
341 # define __returns_nonnull
342 # endif
343 #endif
344
345 /* If fortification mode, we warn about unused results of certain
346 function calls which can lead to problems. */
347 #if __GNUC_PREREQ (3,4) || __glibc_has_attribute (__warn_unused_result__)
348 # define __attribute_warn_unused_result__ \
349 __attribute__ ((__warn_unused_result__))
350 # if defined __USE_FORTIFY_LEVEL && __USE_FORTIFY_LEVEL > 0
351 # define __wur __attribute_warn_unused_result__
352 # endif
353 #else
354 # define __attribute_warn_unused_result__ /* empty */
355 #endif
356 #ifndef __wur
357 # define __wur /* Ignore */
358 #endif
359
360 /* Forces a function to be always inlined. */
361 #if __GNUC_PREREQ (3,2) || __glibc_has_attribute (__always_inline__)
362 /* The Linux kernel defines __always_inline in stddef.h (283d7573), and
363 it conflicts with this definition. Therefore undefine it first to
364 allow either header to be included first. */
365 # undef __always_inline
366 # define __always_inline __inline __attribute__ ((__always_inline__))
367 #else
368 # undef __always_inline
369 # define __always_inline __inline
370 #endif
371
372 /* Associate error messages with the source location of the call site rather
373 than with the source location inside the function. */
374 #if __GNUC_PREREQ (4,3) || __glibc_has_attribute (__artificial__)
375 # define __attribute_artificial__ __attribute__ ((__artificial__))
376 #else
377 # define __attribute_artificial__ /* Ignore */
378 #endif
379
380 /* GCC 4.3 and above with -std=c99 or -std=gnu99 implements ISO C99
381 inline semantics, unless -fgnu89-inline is used. Using __GNUC_STDC_INLINE__
382 or __GNUC_GNU_INLINE is not a good enough check for gcc because gcc versions
383 older than 4.3 may define these macros and still not guarantee GNU inlining
384 semantics.
385
386 clang++ identifies itself as gcc-4.2, but has support for GNU inlining
387 semantics, that can be checked for by using the __GNUC_STDC_INLINE_ and
388 __GNUC_GNU_INLINE__ macro definitions. */
389 #if (!defined __cplusplus || __GNUC_PREREQ (4,3) \
390 || (defined __clang__ && (defined __GNUC_STDC_INLINE__ \
391 || defined __GNUC_GNU_INLINE__)))
392 # if defined __GNUC_STDC_INLINE__ || defined __cplusplus
393 # define __extern_inline extern __inline __attribute__ ((__gnu_inline__))
394 # define __extern_always_inline \
395 extern __always_inline __attribute__ ((__gnu_inline__))
396 # else
397 # define __extern_inline extern __inline
398 # define __extern_always_inline extern __always_inline
399 # endif
400 #endif
401
402 #ifdef __extern_always_inline
403 # define __fortify_function __extern_always_inline __attribute_artificial__
404 #endif
405
406 /* GCC 4.3 and above allow passing all anonymous arguments of an
407 __extern_always_inline function to some other vararg function. */
408 #if __GNUC_PREREQ (4,3)
409 # define __va_arg_pack() __builtin_va_arg_pack ()
410 # define __va_arg_pack_len() __builtin_va_arg_pack_len ()
411 #endif
412
413 /* It is possible to compile containing GCC extensions even if GCC is
414 run in pedantic mode if the uses are carefully marked using the
415 `__extension__' keyword. But this is not generally available before
416 version 2.8. */
417 #if !(__GNUC_PREREQ (2,8) || defined __clang__)
418 # define __extension__ /* Ignore */
419 #endif
420
421 /* __restrict is known in EGCS 1.2 and above, and in clang.
422 It works also in C++ mode (outside of arrays), but only when spelled
423 as '__restrict', not 'restrict'. */
424 #if !(__GNUC_PREREQ (2,92) || __clang_major__ >= 3)
425 # if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
426 # define __restrict restrict
427 # else
428 # define __restrict /* Ignore */
429 # endif
430 #endif
431
432 /* ISO C99 also allows to declare arrays as non-overlapping. The syntax is
433 array_name[restrict]
434 GCC 3.1 and clang support this.
435 This syntax is not usable in C++ mode. */
436 #if (__GNUC_PREREQ (3,1) || __clang_major__ >= 3) && !defined __cplusplus
437 # define __restrict_arr __restrict
438 #else
439 # ifdef __GNUC__
440 # define __restrict_arr /* Not supported in old GCC. */
441 # else
442 # if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
443 # define __restrict_arr restrict
444 # else
445 /* Some other non-C99 compiler. */
446 # define __restrict_arr /* Not supported. */
447 # endif
448 # endif
449 #endif
450
451 #if (__GNUC__ >= 3) || __glibc_has_builtin (__builtin_expect)
452 # define __glibc_unlikely(cond) __builtin_expect ((cond), 0)
453 # define __glibc_likely(cond) __builtin_expect ((cond), 1)
454 #else
455 # define __glibc_unlikely(cond) (cond)
456 # define __glibc_likely(cond) (cond)
457 #endif
458
459 #if (!defined _Noreturn \
460 && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \
461 && !(__GNUC_PREREQ (4,7) \
462 || (3 < __clang_major__ + (5 <= __clang_minor__))))
463 # if __GNUC_PREREQ (2,8)
464 # define _Noreturn __attribute__ ((__noreturn__))
465 # else
466 # define _Noreturn
467 # endif
468 #endif
469
470 #if __GNUC_PREREQ (8, 0)
471 /* Describes a char array whose address can safely be passed as the first
472 argument to strncpy and strncat, as the char array is not necessarily
473 a NUL-terminated string. */
474 # define __attribute_nonstring__ __attribute__ ((__nonstring__))
475 #else
476 # define __attribute_nonstring__
477 #endif
478
479 /* Undefine (also defined in libc-symbols.h). */
480 #undef __attribute_copy__
481 #if __GNUC_PREREQ (9, 0)
482 /* Copies attributes from the declaration or type referenced by
483 the argument. */
484 # define __attribute_copy__(arg) __attribute__ ((__copy__ (arg)))
485 #else
486 # define __attribute_copy__(arg)
487 #endif
488
489 #if (!defined _Static_assert && !defined __cplusplus \
490 && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \
491 && (!(__GNUC_PREREQ (4, 6) || __clang_major__ >= 4) \
492 || defined __STRICT_ANSI__))
493 # define _Static_assert(expr, diagnostic) \
494 extern int (*__Static_assert_function (void)) \
495 [!!sizeof (struct { int __error_if_negative: (expr) ? 2 : -1; })]
496 #endif
497
498 /* Gnulib avoids including these, as they don't work on non-glibc or
499 older glibc platforms. */
500 #ifndef __GNULIB_CDEFS
501 # include <bits/wordsize.h>
502 # include <bits/long-double.h>
503 #endif
504
505 #if __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 1
506 # ifdef __REDIRECT
507
508 /* Alias name defined automatically. */
509 # define __LDBL_REDIR(name, proto) ... unused__ldbl_redir
510 # define __LDBL_REDIR_DECL(name) \
511 extern __typeof (name) name __asm (__ASMNAME ("__" #name "ieee128"));
512
513 /* Alias name defined automatically, with leading underscores. */
514 # define __LDBL_REDIR2_DECL(name) \
515 extern __typeof (__##name) __##name \
516 __asm (__ASMNAME ("__" #name "ieee128"));
517
518 /* Alias name defined manually. */
519 # define __LDBL_REDIR1(name, proto, alias) ... unused__ldbl_redir1
520 # define __LDBL_REDIR1_DECL(name, alias) \
521 extern __typeof (name) name __asm (__ASMNAME (#alias));
522
523 # define __LDBL_REDIR1_NTH(name, proto, alias) \
524 __REDIRECT_NTH (name, proto, alias)
525 # define __REDIRECT_NTH_LDBL(name, proto, alias) \
526 __LDBL_REDIR1_NTH (name, proto, __##alias##ieee128)
527
528 /* Unused. */
529 # define __REDIRECT_LDBL(name, proto, alias) ... unused__redirect_ldbl
530 # define __LDBL_REDIR_NTH(name, proto) ... unused__ldbl_redir_nth
531
532 # else
533 _Static_assert (0, "IEEE 128-bits long double requires redirection on this platform");
534 # endif
535 #elif defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
536 # define __LDBL_COMPAT 1
537 # ifdef __REDIRECT
538 # define __LDBL_REDIR1(name, proto, alias) __REDIRECT (name, proto, alias)
539 # define __LDBL_REDIR(name, proto) \
540 __LDBL_REDIR1 (name, proto, __nldbl_##name)
541 # define __LDBL_REDIR1_NTH(name, proto, alias) __REDIRECT_NTH (name, proto, alias)
542 # define __LDBL_REDIR_NTH(name, proto) \
543 __LDBL_REDIR1_NTH (name, proto, __nldbl_##name)
544 # define __LDBL_REDIR2_DECL(name) \
545 extern __typeof (__##name) __##name __asm (__ASMNAME ("__nldbl___" #name));
546 # define __LDBL_REDIR1_DECL(name, alias) \
547 extern __typeof (name) name __asm (__ASMNAME (#alias));
548 # define __LDBL_REDIR_DECL(name) \
549 extern __typeof (name) name __asm (__ASMNAME ("__nldbl_" #name));
550 # define __REDIRECT_LDBL(name, proto, alias) \
551 __LDBL_REDIR1 (name, proto, __nldbl_##alias)
552 # define __REDIRECT_NTH_LDBL(name, proto, alias) \
553 __LDBL_REDIR1_NTH (name, proto, __nldbl_##alias)
554 # endif
555 #endif
556 #if (!defined __LDBL_COMPAT && __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 0) \
557 || !defined __REDIRECT
558 # define __LDBL_REDIR1(name, proto, alias) name proto
559 # define __LDBL_REDIR(name, proto) name proto
560 # define __LDBL_REDIR1_NTH(name, proto, alias) name proto __THROW
561 # define __LDBL_REDIR_NTH(name, proto) name proto __THROW
562 # define __LDBL_REDIR2_DECL(name)
563 # define __LDBL_REDIR_DECL(name)
564 # ifdef __REDIRECT
565 # define __REDIRECT_LDBL(name, proto, alias) __REDIRECT (name, proto, alias)
566 # define __REDIRECT_NTH_LDBL(name, proto, alias) \
567 __REDIRECT_NTH (name, proto, alias)
568 # endif
569 #endif
570
571 /* __glibc_macro_warning (MESSAGE) issues warning MESSAGE. This is
572 intended for use in preprocessor macros.
573
574 Note: MESSAGE must be a _single_ string; concatenation of string
575 literals is not supported. */
576 #if __GNUC_PREREQ (4,8) || __glibc_clang_prereq (3,5)
577 # define __glibc_macro_warning1(message) _Pragma (#message)
578 # define __glibc_macro_warning(message) \
579 __glibc_macro_warning1 (GCC warning message)
580 #else
581 # define __glibc_macro_warning(msg)
582 #endif
583
584 /* Generic selection (ISO C11) is a C-only feature, available in GCC
585 since version 4.9. Previous versions do not provide generic
586 selection, even though they might set __STDC_VERSION__ to 201112L,
587 when in -std=c11 mode. Thus, we must check for !defined __GNUC__
588 when testing __STDC_VERSION__ for generic selection support.
589 On the other hand, Clang also defines __GNUC__, so a clang-specific
590 check is required to enable the use of generic selection. */
591 #if !defined __cplusplus \
592 && (__GNUC_PREREQ (4, 9) \
593 || __glibc_has_extension (c_generic_selections) \
594 || (!defined __GNUC__ && defined __STDC_VERSION__ \
595 && __STDC_VERSION__ >= 201112L))
596 # define __HAVE_GENERIC_SELECTION 1
597 #else
598 # define __HAVE_GENERIC_SELECTION 0
599 #endif
600
601 #if __GNUC_PREREQ (10, 0)
602 /* Designates a 1-based positional argument ref-index of pointer type
603 that can be used to access size-index elements of the pointed-to
604 array according to access mode, or at least one element when
605 size-index is not provided:
606 access (access-mode, <ref-index> [, <size-index>]) */
607 # define __attr_access(x) __attribute__ ((__access__ x))
608 # if __GNUC_PREREQ (11, 0)
609 # define __attr_access_none(argno) __attribute__ ((__access__ (__none__, argno)))
610 # else
611 # define __attr_access_none(argno)
612 # endif
613 #else
614 # define __attr_access(x)
615 # define __attr_access_none(argno)
616 #endif
617
618 #if __GNUC_PREREQ (11, 0)
619 /* Designates dealloc as a function to call to deallocate objects
620 allocated by the declared function. */
621 # define __attr_dealloc(dealloc, argno) \
622 __attribute__ ((__malloc__ (dealloc, argno)))
623 # define __attr_dealloc_free __attr_dealloc (__builtin_free, 1)
624 #else
625 # define __attr_dealloc(dealloc, argno)
626 # define __attr_dealloc_free
627 #endif
628
629 /* Specify that a function such as setjmp or vfork may return
630 twice. */
631 #if __GNUC_PREREQ (4, 1)
632 # define __attribute_returns_twice__ __attribute__ ((__returns_twice__))
633 #else
634 # define __attribute_returns_twice__ /* Ignore. */
635 #endif
636
637 #endif /* sys/cdefs.h */