1 /* Copyright (C) 1992-2023 Free Software Foundation, Inc.
2 Copyright The GNU Toolchain Authors.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19 #ifndef _SYS_CDEFS_H
20 #define _SYS_CDEFS_H 1
21
22 /* We are almost always included from features.h. */
23 #ifndef _FEATURES_H
24 # include <features.h>
25 #endif
26
27 /* The GNU libc does not support any K&R compilers or the traditional mode
28 of ISO C compilers anymore. Check for some of the combinations not
29 supported anymore. */
30 #if defined __GNUC__ && !defined __STDC__
31 # error "You need a ISO C conforming compiler to use the glibc headers"
32 #endif
33
34 /* Some user header file might have defined this before. */
35 #undef __P
36 #undef __PMT
37
38 /* Compilers that lack __has_attribute may object to
39 #if defined __has_attribute && __has_attribute (...)
40 even though they do not need to evaluate the right-hand side of the &&.
41 Similarly for __has_builtin, etc. */
42 #if (defined __has_attribute \
43 && (!defined __clang_minor__ \
44 || (defined __apple_build_version__ \
45 ? 6000000 <= __apple_build_version__ \
46 : 3 < __clang_major__ + (5 <= __clang_minor__))))
47 # define __glibc_has_attribute(attr) __has_attribute (attr)
48 #else
49 # define __glibc_has_attribute(attr) 0
50 #endif
51 #ifdef __has_builtin
52 # define __glibc_has_builtin(name) __has_builtin (name)
53 #else
54 # define __glibc_has_builtin(name) 0
55 #endif
56 #ifdef __has_extension
57 # define __glibc_has_extension(ext) __has_extension (ext)
58 #else
59 # define __glibc_has_extension(ext) 0
60 #endif
61
62 #if defined __GNUC__ || defined __clang__
63
64 /* All functions, except those with callbacks or those that
65 synchronize memory, are leaf functions. */
66 # if __GNUC_PREREQ (4, 6) && !defined _LIBC
67 # define __LEAF , __leaf__
68 # define __LEAF_ATTR __attribute__ ((__leaf__))
69 # else
70 # define __LEAF
71 # define __LEAF_ATTR
72 # endif
73
74 /* GCC can always grok prototypes. For C++ programs we add throw()
75 to help it optimize the function calls. But this only works with
76 gcc 2.8.x and egcs. For gcc 3.4 and up we even mark C functions
77 as non-throwing using a function attribute since programs can use
78 the -fexceptions options for C code as well. */
79 # if !defined __cplusplus \
80 && (__GNUC_PREREQ (3, 4) || __glibc_has_attribute (__nothrow__))
81 # define __THROW __attribute__ ((__nothrow__ __LEAF))
82 # define __THROWNL __attribute__ ((__nothrow__))
83 # define __NTH(fct) __attribute__ ((__nothrow__ __LEAF)) fct
84 # define __NTHNL(fct) __attribute__ ((__nothrow__)) fct
85 # else
86 # if defined __cplusplus && (__GNUC_PREREQ (2,8) || __clang_major >= 4)
87 # if __cplusplus >= 201103L
88 # define __THROW noexcept (true)
89 # else
90 # define __THROW throw ()
91 # endif
92 # define __THROWNL __THROW
93 # define __NTH(fct) __LEAF_ATTR fct __THROW
94 # define __NTHNL(fct) fct __THROW
95 # else
96 # define __THROW
97 # define __THROWNL
98 # define __NTH(fct) fct
99 # define __NTHNL(fct) fct
100 # endif
101 # endif
102
103 #else /* Not GCC or clang. */
104
105 # if (defined __cplusplus \
106 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L))
107 # define __inline inline
108 # else
109 # define __inline /* No inline functions. */
110 # endif
111
112 # define __THROW
113 # define __THROWNL
114 # define __NTH(fct) fct
115
116 #endif /* GCC || clang. */
117
118 /* These two macros are not used in glibc anymore. They are kept here
119 only because some other projects expect the macros to be defined. */
120 #define __P(args) args
121 #define __PMT(args) args
122
123 /* For these things, GCC behaves the ANSI way normally,
124 and the non-ANSI way under -traditional. */
125
126 #define __CONCAT(x,y) x ## y
127 #define __STRING(x) #x
128
129 /* This is not a typedef so `const __ptr_t' does the right thing. */
130 #define __ptr_t void *
131
132
133 /* C++ needs to know that types and declarations are C, not C++. */
134 #ifdef __cplusplus
135 # define __BEGIN_DECLS extern "C" {
136 # define __END_DECLS }
137 #else
138 # define __BEGIN_DECLS
139 # define __END_DECLS
140 #endif
141
142
143 /* Gnulib avoids these definitions, as they don't work on non-glibc platforms.
144 In particular, __bos and __bos0 are defined differently in the Android libc.
145 */
146 #ifndef __GNULIB_CDEFS
147
148 /* Fortify support. */
149 # define __bos(ptr) __builtin_object_size (ptr, __USE_FORTIFY_LEVEL > 1)
150 # define __bos0(ptr) __builtin_object_size (ptr, 0)
151
152 /* Use __builtin_dynamic_object_size at _FORTIFY_SOURCE=3 when available. */
153 # if __USE_FORTIFY_LEVEL == 3 && (__glibc_clang_prereq (9, 0) \
154 || __GNUC_PREREQ (12, 0))
155 # define __glibc_objsize0(__o) __builtin_dynamic_object_size (__o, 0)
156 # define __glibc_objsize(__o) __builtin_dynamic_object_size (__o, 1)
157 # else
158 # define __glibc_objsize0(__o) __bos0 (__o)
159 # define __glibc_objsize(__o) __bos (__o)
160 # endif
161
162 /* Compile time conditions to choose between the regular, _chk and _chk_warn
163 variants. These conditions should get evaluated to constant and optimized
164 away. */
165
166 # define __glibc_safe_len_cond(__l, __s, __osz) ((__l) <= (__osz) / (__s))
167 # define __glibc_unsigned_or_positive(__l) \
168 ((__typeof (__l)) 0 < (__typeof (__l)) -1 \
169 || (__builtin_constant_p (__l) && (__l) > 0))
170
171 /* Length is known to be safe at compile time if the __L * __S <= __OBJSZ
172 condition can be folded to a constant and if it is true, or unknown (-1) */
173 # define __glibc_safe_or_unknown_len(__l, __s, __osz) \
174 ((__osz) == (__SIZE_TYPE__) -1 \
175 || (__glibc_unsigned_or_positive (__l) \
176 && __builtin_constant_p (__glibc_safe_len_cond ((__SIZE_TYPE__) (__l), \
177 (__s), (__osz))) \
178 && __glibc_safe_len_cond ((__SIZE_TYPE__) (__l), (__s), (__osz))))
179
180 /* Conversely, we know at compile time that the length is unsafe if the
181 __L * __S <= __OBJSZ condition can be folded to a constant and if it is
182 false. */
183 # define __glibc_unsafe_len(__l, __s, __osz) \
184 (__glibc_unsigned_or_positive (__l) \
185 && __builtin_constant_p (__glibc_safe_len_cond ((__SIZE_TYPE__) (__l), \
186 __s, __osz)) \
187 && !__glibc_safe_len_cond ((__SIZE_TYPE__) (__l), __s, __osz))
188
189 /* Fortify function f. __f_alias, __f_chk and __f_chk_warn must be
190 declared. */
191
192 # define __glibc_fortify(f, __l, __s, __osz, ...) \
193 (__glibc_safe_or_unknown_len (__l, __s, __osz) \
194 ? __ ## f ## _alias (__VA_ARGS__) \
195 : (__glibc_unsafe_len (__l, __s, __osz) \
196 ? __ ## f ## _chk_warn (__VA_ARGS__, __osz) \
197 : __ ## f ## _chk (__VA_ARGS__, __osz))) \
198
199 /* Fortify function f, where object size argument passed to f is the number of
200 elements and not total size. */
201
202 # define __glibc_fortify_n(f, __l, __s, __osz, ...) \
203 (__glibc_safe_or_unknown_len (__l, __s, __osz) \
204 ? __ ## f ## _alias (__VA_ARGS__) \
205 : (__glibc_unsafe_len (__l, __s, __osz) \
206 ? __ ## f ## _chk_warn (__VA_ARGS__, (__osz) / (__s)) \
207 : __ ## f ## _chk (__VA_ARGS__, (__osz) / (__s)))) \
208
209 #endif
210
211
212 #if __GNUC_PREREQ (4,3)
213 # define __warnattr(msg) __attribute__((__warning__ (msg)))
214 # define __errordecl(name, msg) \
215 extern void name (void) __attribute__((__error__ (msg)))
216 #else
217 # define __warnattr(msg)
218 # define __errordecl(name, msg) extern void name (void)
219 #endif
220
221 /* Support for flexible arrays.
222 Headers that should use flexible arrays only if they're "real"
223 (e.g. only if they won't affect sizeof()) should test
224 #if __glibc_c99_flexarr_available. */
225 #if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L && !defined __HP_cc
226 # define __flexarr []
227 # define __glibc_c99_flexarr_available 1
228 #elif __GNUC_PREREQ (2,97) || defined __clang__
229 /* GCC 2.97 and clang support C99 flexible array members as an extension,
230 even when in C89 mode or compiling C++ (any version). */
231 # define __flexarr []
232 # define __glibc_c99_flexarr_available 1
233 #elif defined __GNUC__
234 /* Pre-2.97 GCC did not support C99 flexible arrays but did have
235 an equivalent extension with slightly different notation. */
236 # define __flexarr [0]
237 # define __glibc_c99_flexarr_available 1
238 #else
239 /* Some other non-C99 compiler. Approximate with [1]. */
240 # define __flexarr [1]
241 # define __glibc_c99_flexarr_available 0
242 #endif
243
244
245 /* __asm__ ("xyz") is used throughout the headers to rename functions
246 at the assembly language level. This is wrapped by the __REDIRECT
247 macro, in order to support compilers that can do this some other
248 way. When compilers don't support asm-names at all, we have to do
249 preprocessor tricks instead (which don't have exactly the right
250 semantics, but it's the best we can do).
251
252 Example:
253 int __REDIRECT(setpgrp, (__pid_t pid, __pid_t pgrp), setpgid); */
254
255 #if (defined __GNUC__ && __GNUC__ >= 2) || (__clang_major__ >= 4)
256
257 # define __REDIRECT(name, proto, alias) name proto __asm__ (__ASMNAME (#alias))
258 # ifdef __cplusplus
259 # define __REDIRECT_NTH(name, proto, alias) \
260 name proto __THROW __asm__ (__ASMNAME (#alias))
261 # define __REDIRECT_NTHNL(name, proto, alias) \
262 name proto __THROWNL __asm__ (__ASMNAME (#alias))
263 # else
264 # define __REDIRECT_NTH(name, proto, alias) \
265 name proto __asm__ (__ASMNAME (#alias)) __THROW
266 # define __REDIRECT_NTHNL(name, proto, alias) \
267 name proto __asm__ (__ASMNAME (#alias)) __THROWNL
268 # endif
269 # define __ASMNAME(cname) __ASMNAME2 (__USER_LABEL_PREFIX__, cname)
270 # define __ASMNAME2(prefix, cname) __STRING (prefix) cname
271
272 /*
273 #elif __SOME_OTHER_COMPILER__
274
275 # define __REDIRECT(name, proto, alias) name proto; \
276 _Pragma("let " #name " = " #alias)
277 */
278 #endif
279
280 /* GCC and clang have various useful declarations that can be made with
281 the '__attribute__' syntax. All of the ways we use this do fine if
282 they are omitted for compilers that don't understand it. */
283 #if !(defined __GNUC__ || defined __clang__)
284 # define __attribute__(xyz) /* Ignore */
285 #endif
286
287 /* At some point during the gcc 2.96 development the `malloc' attribute
288 for functions was introduced. We don't want to use it unconditionally
289 (although this would be possible) since it generates warnings. */
290 #if __GNUC_PREREQ (2,96) || __glibc_has_attribute (__malloc__)
291 # define __attribute_malloc__ __attribute__ ((__malloc__))
292 #else
293 # define __attribute_malloc__ /* Ignore */
294 #endif
295
296 /* Tell the compiler which arguments to an allocation function
297 indicate the size of the allocation. */
298 #if __GNUC_PREREQ (4, 3)
299 # define __attribute_alloc_size__(params) \
300 __attribute__ ((__alloc_size__ params))
301 #else
302 # define __attribute_alloc_size__(params) /* Ignore. */
303 #endif
304
305 /* Tell the compiler which argument to an allocation function
306 indicates the alignment of the allocation. */
307 #if __GNUC_PREREQ (4, 9) || __glibc_has_attribute (__alloc_align__)
308 # define __attribute_alloc_align__(param) \
309 __attribute__ ((__alloc_align__ param))
310 #else
311 # define __attribute_alloc_align__(param) /* Ignore. */
312 #endif
313
314 /* At some point during the gcc 2.96 development the `pure' attribute
315 for functions was introduced. We don't want to use it unconditionally
316 (although this would be possible) since it generates warnings. */
317 #if __GNUC_PREREQ (2,96) || __glibc_has_attribute (__pure__)
318 # define __attribute_pure__ __attribute__ ((__pure__))
319 #else
320 # define __attribute_pure__ /* Ignore */
321 #endif
322
323 /* This declaration tells the compiler that the value is constant. */
324 #if __GNUC_PREREQ (2,5) || __glibc_has_attribute (__const__)
325 # define __attribute_const__ __attribute__ ((__const__))
326 #else
327 # define __attribute_const__ /* Ignore */
328 #endif
329
330 #if __GNUC_PREREQ (2,7) || __glibc_has_attribute (__unused__)
331 # define __attribute_maybe_unused__ __attribute__ ((__unused__))
332 #else
333 # define __attribute_maybe_unused__ /* Ignore */
334 #endif
335
336 /* At some point during the gcc 3.1 development the `used' attribute
337 for functions was introduced. We don't want to use it unconditionally
338 (although this would be possible) since it generates warnings. */
339 #if __GNUC_PREREQ (3,1) || __glibc_has_attribute (__used__)
340 # define __attribute_used__ __attribute__ ((__used__))
341 # define __attribute_noinline__ __attribute__ ((__noinline__))
342 #else
343 # define __attribute_used__ __attribute__ ((__unused__))
344 # define __attribute_noinline__ /* Ignore */
345 #endif
346
347 /* Since version 3.2, gcc allows marking deprecated functions. */
348 #if __GNUC_PREREQ (3,2) || __glibc_has_attribute (__deprecated__)
349 # define __attribute_deprecated__ __attribute__ ((__deprecated__))
350 #else
351 # define __attribute_deprecated__ /* Ignore */
352 #endif
353
354 /* Since version 4.5, gcc also allows one to specify the message printed
355 when a deprecated function is used. clang claims to be gcc 4.2, but
356 may also support this feature. */
357 #if __GNUC_PREREQ (4,5) \
358 || __glibc_has_extension (__attribute_deprecated_with_message__)
359 # define __attribute_deprecated_msg__(msg) \
360 __attribute__ ((__deprecated__ (msg)))
361 #else
362 # define __attribute_deprecated_msg__(msg) __attribute_deprecated__
363 #endif
364
365 /* At some point during the gcc 2.8 development the `format_arg' attribute
366 for functions was introduced. We don't want to use it unconditionally
367 (although this would be possible) since it generates warnings.
368 If several `format_arg' attributes are given for the same function, in
369 gcc-3.0 and older, all but the last one are ignored. In newer gccs,
370 all designated arguments are considered. */
371 #if __GNUC_PREREQ (2,8) || __glibc_has_attribute (__format_arg__)
372 # define __attribute_format_arg__(x) __attribute__ ((__format_arg__ (x)))
373 #else
374 # define __attribute_format_arg__(x) /* Ignore */
375 #endif
376
377 /* At some point during the gcc 2.97 development the `strfmon' format
378 attribute for functions was introduced. We don't want to use it
379 unconditionally (although this would be possible) since it
380 generates warnings. */
381 #if __GNUC_PREREQ (2,97) || __glibc_has_attribute (__format__)
382 # define __attribute_format_strfmon__(a,b) \
383 __attribute__ ((__format__ (__strfmon__, a, b)))
384 #else
385 # define __attribute_format_strfmon__(a,b) /* Ignore */
386 #endif
387
388 /* The nonnull function attribute marks pointer parameters that
389 must not be NULL. This has the name __nonnull in glibc,
390 and __attribute_nonnull__ in files shared with Gnulib to avoid
391 collision with a different __nonnull in DragonFlyBSD 5.9. */
392 #ifndef __attribute_nonnull__
393 # if __GNUC_PREREQ (3,3) || __glibc_has_attribute (__nonnull__)
394 # define __attribute_nonnull__(params) __attribute__ ((__nonnull__ params))
395 # else
396 # define __attribute_nonnull__(params)
397 # endif
398 #endif
399 #ifndef __nonnull
400 # define __nonnull(params) __attribute_nonnull__ (params)
401 #endif
402
403 /* The returns_nonnull function attribute marks the return type of the function
404 as always being non-null. */
405 #ifndef __returns_nonnull
406 # if __GNUC_PREREQ (4, 9) || __glibc_has_attribute (__returns_nonnull__)
407 # define __returns_nonnull __attribute__ ((__returns_nonnull__))
408 # else
409 # define __returns_nonnull
410 # endif
411 #endif
412
413 /* If fortification mode, we warn about unused results of certain
414 function calls which can lead to problems. */
415 #if __GNUC_PREREQ (3,4) || __glibc_has_attribute (__warn_unused_result__)
416 # define __attribute_warn_unused_result__ \
417 __attribute__ ((__warn_unused_result__))
418 # if defined __USE_FORTIFY_LEVEL && __USE_FORTIFY_LEVEL > 0
419 # define __wur __attribute_warn_unused_result__
420 # endif
421 #else
422 # define __attribute_warn_unused_result__ /* empty */
423 #endif
424 #ifndef __wur
425 # define __wur /* Ignore */
426 #endif
427
428 /* Forces a function to be always inlined. */
429 #if __GNUC_PREREQ (3,2) || __glibc_has_attribute (__always_inline__)
430 /* The Linux kernel defines __always_inline in stddef.h (283d7573), and
431 it conflicts with this definition. Therefore undefine it first to
432 allow either header to be included first. */
433 # undef __always_inline
434 # define __always_inline __inline __attribute__ ((__always_inline__))
435 #else
436 # undef __always_inline
437 # define __always_inline __inline
438 #endif
439
440 /* Associate error messages with the source location of the call site rather
441 than with the source location inside the function. */
442 #if __GNUC_PREREQ (4,3) || __glibc_has_attribute (__artificial__)
443 # define __attribute_artificial__ __attribute__ ((__artificial__))
444 #else
445 # define __attribute_artificial__ /* Ignore */
446 #endif
447
448 /* GCC 4.3 and above with -std=c99 or -std=gnu99 implements ISO C99
449 inline semantics, unless -fgnu89-inline is used. Using __GNUC_STDC_INLINE__
450 or __GNUC_GNU_INLINE is not a good enough check for gcc because gcc versions
451 older than 4.3 may define these macros and still not guarantee GNU inlining
452 semantics.
453
454 clang++ identifies itself as gcc-4.2, but has support for GNU inlining
455 semantics, that can be checked for by using the __GNUC_STDC_INLINE_ and
456 __GNUC_GNU_INLINE__ macro definitions. */
457 #if (!defined __cplusplus || __GNUC_PREREQ (4,3) \
458 || (defined __clang__ && (defined __GNUC_STDC_INLINE__ \
459 || defined __GNUC_GNU_INLINE__)))
460 # if defined __GNUC_STDC_INLINE__ || defined __cplusplus
461 # define __extern_inline extern __inline __attribute__ ((__gnu_inline__))
462 # define __extern_always_inline \
463 extern __always_inline __attribute__ ((__gnu_inline__))
464 # else
465 # define __extern_inline extern __inline
466 # define __extern_always_inline extern __always_inline
467 # endif
468 #endif
469
470 #ifdef __extern_always_inline
471 # define __fortify_function __extern_always_inline __attribute_artificial__
472 #endif
473
474 /* GCC 4.3 and above allow passing all anonymous arguments of an
475 __extern_always_inline function to some other vararg function. */
476 #if __GNUC_PREREQ (4,3)
477 # define __va_arg_pack() __builtin_va_arg_pack ()
478 # define __va_arg_pack_len() __builtin_va_arg_pack_len ()
479 #endif
480
481 /* It is possible to compile containing GCC extensions even if GCC is
482 run in pedantic mode if the uses are carefully marked using the
483 `__extension__' keyword. But this is not generally available before
484 version 2.8. */
485 #if !(__GNUC_PREREQ (2,8) || defined __clang__)
486 # define __extension__ /* Ignore */
487 #endif
488
489 /* __restrict is known in EGCS 1.2 and above, and in clang.
490 It works also in C++ mode (outside of arrays), but only when spelled
491 as '__restrict', not 'restrict'. */
492 #if !(__GNUC_PREREQ (2,92) || __clang_major__ >= 3)
493 # if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
494 # define __restrict restrict
495 # else
496 # define __restrict /* Ignore */
497 # endif
498 #endif
499
500 /* ISO C99 also allows to declare arrays as non-overlapping. The syntax is
501 array_name[restrict]
502 GCC 3.1 and clang support this.
503 This syntax is not usable in C++ mode. */
504 #if (__GNUC_PREREQ (3,1) || __clang_major__ >= 3) && !defined __cplusplus
505 # define __restrict_arr __restrict
506 #else
507 # ifdef __GNUC__
508 # define __restrict_arr /* Not supported in old GCC. */
509 # else
510 # if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
511 # define __restrict_arr restrict
512 # else
513 /* Some other non-C99 compiler. */
514 # define __restrict_arr /* Not supported. */
515 # endif
516 # endif
517 #endif
518
519 #if (__GNUC__ >= 3) || __glibc_has_builtin (__builtin_expect)
520 # define __glibc_unlikely(cond) __builtin_expect ((cond), 0)
521 # define __glibc_likely(cond) __builtin_expect ((cond), 1)
522 #else
523 # define __glibc_unlikely(cond) (cond)
524 # define __glibc_likely(cond) (cond)
525 #endif
526
527 #if (!defined _Noreturn \
528 && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \
529 && !(__GNUC_PREREQ (4,7) \
530 || (3 < __clang_major__ + (5 <= __clang_minor__))))
531 # if __GNUC_PREREQ (2,8)
532 # define _Noreturn __attribute__ ((__noreturn__))
533 # else
534 # define _Noreturn
535 # endif
536 #endif
537
538 #if __GNUC_PREREQ (8, 0)
539 /* Describes a char array whose address can safely be passed as the first
540 argument to strncpy and strncat, as the char array is not necessarily
541 a NUL-terminated string. */
542 # define __attribute_nonstring__ __attribute__ ((__nonstring__))
543 #else
544 # define __attribute_nonstring__
545 #endif
546
547 /* Undefine (also defined in libc-symbols.h). */
548 #undef __attribute_copy__
549 #if __GNUC_PREREQ (9, 0)
550 /* Copies attributes from the declaration or type referenced by
551 the argument. */
552 # define __attribute_copy__(arg) __attribute__ ((__copy__ (arg)))
553 #else
554 # define __attribute_copy__(arg)
555 #endif
556
557 #if (!defined _Static_assert && !defined __cplusplus \
558 && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \
559 && (!(__GNUC_PREREQ (4, 6) || __clang_major__ >= 4) \
560 || defined __STRICT_ANSI__))
561 # define _Static_assert(expr, diagnostic) \
562 extern int (*__Static_assert_function (void)) \
563 [!!sizeof (struct { int __error_if_negative: (expr) ? 2 : -1; })]
564 #endif
565
566 /* Gnulib avoids including these, as they don't work on non-glibc or
567 older glibc platforms. */
568 #ifndef __GNULIB_CDEFS
569 # include <bits/wordsize.h>
570 # include <bits/long-double.h>
571 #endif
572
573 #if __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 1
574 # ifdef __REDIRECT
575
576 /* Alias name defined automatically. */
577 # define __LDBL_REDIR(name, proto) ... unused__ldbl_redir
578 # define __LDBL_REDIR_DECL(name) \
579 extern __typeof (name) name __asm (__ASMNAME ("__" #name "ieee128"));
580
581 /* Alias name defined automatically, with leading underscores. */
582 # define __LDBL_REDIR2_DECL(name) \
583 extern __typeof (__##name) __##name \
584 __asm (__ASMNAME ("__" #name "ieee128"));
585
586 /* Alias name defined manually. */
587 # define __LDBL_REDIR1(name, proto, alias) ... unused__ldbl_redir1
588 # define __LDBL_REDIR1_DECL(name, alias) \
589 extern __typeof (name) name __asm (__ASMNAME (#alias));
590
591 # define __LDBL_REDIR1_NTH(name, proto, alias) \
592 __REDIRECT_NTH (name, proto, alias)
593 # define __REDIRECT_NTH_LDBL(name, proto, alias) \
594 __LDBL_REDIR1_NTH (name, proto, __##alias##ieee128)
595
596 /* Unused. */
597 # define __REDIRECT_LDBL(name, proto, alias) ... unused__redirect_ldbl
598 # define __LDBL_REDIR_NTH(name, proto) ... unused__ldbl_redir_nth
599
600 # else
601 _Static_assert (0, "IEEE 128-bits long double requires redirection on this platform");
602 # endif
603 #elif defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
604 # define __LDBL_COMPAT 1
605 # ifdef __REDIRECT
606 # define __LDBL_REDIR1(name, proto, alias) __REDIRECT (name, proto, alias)
607 # define __LDBL_REDIR(name, proto) \
608 __LDBL_REDIR1 (name, proto, __nldbl_##name)
609 # define __LDBL_REDIR1_NTH(name, proto, alias) __REDIRECT_NTH (name, proto, alias)
610 # define __LDBL_REDIR_NTH(name, proto) \
611 __LDBL_REDIR1_NTH (name, proto, __nldbl_##name)
612 # define __LDBL_REDIR2_DECL(name) \
613 extern __typeof (__##name) __##name __asm (__ASMNAME ("__nldbl___" #name));
614 # define __LDBL_REDIR1_DECL(name, alias) \
615 extern __typeof (name) name __asm (__ASMNAME (#alias));
616 # define __LDBL_REDIR_DECL(name) \
617 extern __typeof (name) name __asm (__ASMNAME ("__nldbl_" #name));
618 # define __REDIRECT_LDBL(name, proto, alias) \
619 __LDBL_REDIR1 (name, proto, __nldbl_##alias)
620 # define __REDIRECT_NTH_LDBL(name, proto, alias) \
621 __LDBL_REDIR1_NTH (name, proto, __nldbl_##alias)
622 # endif
623 #endif
624 #if (!defined __LDBL_COMPAT && __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 0) \
625 || !defined __REDIRECT
626 # define __LDBL_REDIR1(name, proto, alias) name proto
627 # define __LDBL_REDIR(name, proto) name proto
628 # define __LDBL_REDIR1_NTH(name, proto, alias) name proto __THROW
629 # define __LDBL_REDIR_NTH(name, proto) name proto __THROW
630 # define __LDBL_REDIR2_DECL(name)
631 # define __LDBL_REDIR_DECL(name)
632 # ifdef __REDIRECT
633 # define __REDIRECT_LDBL(name, proto, alias) __REDIRECT (name, proto, alias)
634 # define __REDIRECT_NTH_LDBL(name, proto, alias) \
635 __REDIRECT_NTH (name, proto, alias)
636 # endif
637 #endif
638
639 /* __glibc_macro_warning (MESSAGE) issues warning MESSAGE. This is
640 intended for use in preprocessor macros.
641
642 Note: MESSAGE must be a _single_ string; concatenation of string
643 literals is not supported. */
644 #if __GNUC_PREREQ (4,8) || __glibc_clang_prereq (3,5)
645 # define __glibc_macro_warning1(message) _Pragma (#message)
646 # define __glibc_macro_warning(message) \
647 __glibc_macro_warning1 (GCC warning message)
648 #else
649 # define __glibc_macro_warning(msg)
650 #endif
651
652 /* Generic selection (ISO C11) is a C-only feature, available in GCC
653 since version 4.9. Previous versions do not provide generic
654 selection, even though they might set __STDC_VERSION__ to 201112L,
655 when in -std=c11 mode. Thus, we must check for !defined __GNUC__
656 when testing __STDC_VERSION__ for generic selection support.
657 On the other hand, Clang also defines __GNUC__, so a clang-specific
658 check is required to enable the use of generic selection. */
659 #if !defined __cplusplus \
660 && (__GNUC_PREREQ (4, 9) \
661 || __glibc_has_extension (c_generic_selections) \
662 || (!defined __GNUC__ && defined __STDC_VERSION__ \
663 && __STDC_VERSION__ >= 201112L))
664 # define __HAVE_GENERIC_SELECTION 1
665 #else
666 # define __HAVE_GENERIC_SELECTION 0
667 #endif
668
669 #if __GNUC_PREREQ (10, 0)
670 /* Designates a 1-based positional argument ref-index of pointer type
671 that can be used to access size-index elements of the pointed-to
672 array according to access mode, or at least one element when
673 size-index is not provided:
674 access (access-mode, <ref-index> [, <size-index>]) */
675 # define __attr_access(x) __attribute__ ((__access__ x))
676 /* For _FORTIFY_SOURCE == 3 we use __builtin_dynamic_object_size, which may
677 use the access attribute to get object sizes from function definition
678 arguments, so we can't use them on functions we fortify. Drop the object
679 size hints for such functions. */
680 # if __USE_FORTIFY_LEVEL == 3
681 # define __fortified_attr_access(a, o, s) __attribute__ ((__access__ (a, o)))
682 # else
683 # define __fortified_attr_access(a, o, s) __attr_access ((a, o, s))
684 # endif
685 # if __GNUC_PREREQ (11, 0)
686 # define __attr_access_none(argno) __attribute__ ((__access__ (__none__, argno)))
687 # else
688 # define __attr_access_none(argno)
689 # endif
690 #else
691 # define __fortified_attr_access(a, o, s)
692 # define __attr_access(x)
693 # define __attr_access_none(argno)
694 #endif
695
696 #if __GNUC_PREREQ (11, 0)
697 /* Designates dealloc as a function to call to deallocate objects
698 allocated by the declared function. */
699 # define __attr_dealloc(dealloc, argno) \
700 __attribute__ ((__malloc__ (dealloc, argno)))
701 # define __attr_dealloc_free __attr_dealloc (__builtin_free, 1)
702 #else
703 # define __attr_dealloc(dealloc, argno)
704 # define __attr_dealloc_free
705 #endif
706
707 /* Specify that a function such as setjmp or vfork may return
708 twice. */
709 #if __GNUC_PREREQ (4, 1)
710 # define __attribute_returns_twice__ __attribute__ ((__returns_twice__))
711 #else
712 # define __attribute_returns_twice__ /* Ignore. */
713 #endif
714
715 #endif /* sys/cdefs.h */