1 /* Copyright (C) 1992-2022 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 /* Fortify support. */
144 #define __bos(ptr) __builtin_object_size (ptr, __USE_FORTIFY_LEVEL > 1)
145 #define __bos0(ptr) __builtin_object_size (ptr, 0)
146
147 /* Use __builtin_dynamic_object_size at _FORTIFY_SOURCE=3 when available. */
148 #if __USE_FORTIFY_LEVEL == 3 && (__glibc_clang_prereq (9, 0) \
149 || __GNUC_PREREQ (12, 0))
150 # define __glibc_objsize0(__o) __builtin_dynamic_object_size (__o, 0)
151 # define __glibc_objsize(__o) __builtin_dynamic_object_size (__o, 1)
152 #else
153 # define __glibc_objsize0(__o) __bos0 (__o)
154 # define __glibc_objsize(__o) __bos (__o)
155 #endif
156
157 /* Compile time conditions to choose between the regular, _chk and _chk_warn
158 variants. These conditions should get evaluated to constant and optimized
159 away. */
160
161 #define __glibc_safe_len_cond(__l, __s, __osz) ((__l) <= (__osz) / (__s))
162 #define __glibc_unsigned_or_positive(__l) \
163 ((__typeof (__l)) 0 < (__typeof (__l)) -1 \
164 || (__builtin_constant_p (__l) && (__l) > 0))
165
166 /* Length is known to be safe at compile time if the __L * __S <= __OBJSZ
167 condition can be folded to a constant and if it is true, or unknown (-1) */
168 #define __glibc_safe_or_unknown_len(__l, __s, __osz) \
169 ((__osz) == (__SIZE_TYPE__) -1 \
170 || (__glibc_unsigned_or_positive (__l) \
171 && __builtin_constant_p (__glibc_safe_len_cond ((__SIZE_TYPE__) (__l), \
172 (__s), (__osz))) \
173 && __glibc_safe_len_cond ((__SIZE_TYPE__) (__l), (__s), (__osz))))
174
175 /* Conversely, we know at compile time that the length is unsafe if the
176 __L * __S <= __OBJSZ condition can be folded to a constant and if it is
177 false. */
178 #define __glibc_unsafe_len(__l, __s, __osz) \
179 (__glibc_unsigned_or_positive (__l) \
180 && __builtin_constant_p (__glibc_safe_len_cond ((__SIZE_TYPE__) (__l), \
181 __s, __osz)) \
182 && !__glibc_safe_len_cond ((__SIZE_TYPE__) (__l), __s, __osz))
183
184 /* Fortify function f. __f_alias, __f_chk and __f_chk_warn must be
185 declared. */
186
187 #define __glibc_fortify(f, __l, __s, __osz, ...) \
188 (__glibc_safe_or_unknown_len (__l, __s, __osz) \
189 ? __ ## f ## _alias (__VA_ARGS__) \
190 : (__glibc_unsafe_len (__l, __s, __osz) \
191 ? __ ## f ## _chk_warn (__VA_ARGS__, __osz) \
192 : __ ## f ## _chk (__VA_ARGS__, __osz))) \
193
194 /* Fortify function f, where object size argument passed to f is the number of
195 elements and not total size. */
196
197 #define __glibc_fortify_n(f, __l, __s, __osz, ...) \
198 (__glibc_safe_or_unknown_len (__l, __s, __osz) \
199 ? __ ## f ## _alias (__VA_ARGS__) \
200 : (__glibc_unsafe_len (__l, __s, __osz) \
201 ? __ ## f ## _chk_warn (__VA_ARGS__, (__osz) / (__s)) \
202 : __ ## f ## _chk (__VA_ARGS__, (__osz) / (__s)))) \
203
204 #if __GNUC_PREREQ (4,3)
205 # define __warnattr(msg) __attribute__((__warning__ (msg)))
206 # define __errordecl(name, msg) \
207 extern void name (void) __attribute__((__error__ (msg)))
208 #else
209 # define __warnattr(msg)
210 # define __errordecl(name, msg) extern void name (void)
211 #endif
212
213 /* Support for flexible arrays.
214 Headers that should use flexible arrays only if they're "real"
215 (e.g. only if they won't affect sizeof()) should test
216 #if __glibc_c99_flexarr_available. */
217 #if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L && !defined __HP_cc
218 # define __flexarr []
219 # define __glibc_c99_flexarr_available 1
220 #elif __GNUC_PREREQ (2,97) || defined __clang__
221 /* GCC 2.97 and clang support C99 flexible array members as an extension,
222 even when in C89 mode or compiling C++ (any version). */
223 # define __flexarr []
224 # define __glibc_c99_flexarr_available 1
225 #elif defined __GNUC__
226 /* Pre-2.97 GCC did not support C99 flexible arrays but did have
227 an equivalent extension with slightly different notation. */
228 # define __flexarr [0]
229 # define __glibc_c99_flexarr_available 1
230 #else
231 /* Some other non-C99 compiler. Approximate with [1]. */
232 # define __flexarr [1]
233 # define __glibc_c99_flexarr_available 0
234 #endif
235
236
237 /* __asm__ ("xyz") is used throughout the headers to rename functions
238 at the assembly language level. This is wrapped by the __REDIRECT
239 macro, in order to support compilers that can do this some other
240 way. When compilers don't support asm-names at all, we have to do
241 preprocessor tricks instead (which don't have exactly the right
242 semantics, but it's the best we can do).
243
244 Example:
245 int __REDIRECT(setpgrp, (__pid_t pid, __pid_t pgrp), setpgid); */
246
247 #if (defined __GNUC__ && __GNUC__ >= 2) || (__clang_major__ >= 4)
248
249 # define __REDIRECT(name, proto, alias) name proto __asm__ (__ASMNAME (#alias))
250 # ifdef __cplusplus
251 # define __REDIRECT_NTH(name, proto, alias) \
252 name proto __THROW __asm__ (__ASMNAME (#alias))
253 # define __REDIRECT_NTHNL(name, proto, alias) \
254 name proto __THROWNL __asm__ (__ASMNAME (#alias))
255 # else
256 # define __REDIRECT_NTH(name, proto, alias) \
257 name proto __asm__ (__ASMNAME (#alias)) __THROW
258 # define __REDIRECT_NTHNL(name, proto, alias) \
259 name proto __asm__ (__ASMNAME (#alias)) __THROWNL
260 # endif
261 # define __ASMNAME(cname) __ASMNAME2 (__USER_LABEL_PREFIX__, cname)
262 # define __ASMNAME2(prefix, cname) __STRING (prefix) cname
263
264 /*
265 #elif __SOME_OTHER_COMPILER__
266
267 # define __REDIRECT(name, proto, alias) name proto; \
268 _Pragma("let " #name " = " #alias)
269 */
270 #endif
271
272 /* GCC and clang have various useful declarations that can be made with
273 the '__attribute__' syntax. All of the ways we use this do fine if
274 they are omitted for compilers that don't understand it. */
275 #if !(defined __GNUC__ || defined __clang__)
276 # define __attribute__(xyz) /* Ignore */
277 #endif
278
279 /* At some point during the gcc 2.96 development the `malloc' attribute
280 for functions was introduced. We don't want to use it unconditionally
281 (although this would be possible) since it generates warnings. */
282 #if __GNUC_PREREQ (2,96) || __glibc_has_attribute (__malloc__)
283 # define __attribute_malloc__ __attribute__ ((__malloc__))
284 #else
285 # define __attribute_malloc__ /* Ignore */
286 #endif
287
288 /* Tell the compiler which arguments to an allocation function
289 indicate the size of the allocation. */
290 #if __GNUC_PREREQ (4, 3)
291 # define __attribute_alloc_size__(params) \
292 __attribute__ ((__alloc_size__ params))
293 #else
294 # define __attribute_alloc_size__(params) /* Ignore. */
295 #endif
296
297 /* Tell the compiler which argument to an allocation function
298 indicates the alignment of the allocation. */
299 #if __GNUC_PREREQ (4, 9) || __glibc_has_attribute (__alloc_align__)
300 # define __attribute_alloc_align__(param) \
301 __attribute__ ((__alloc_align__ param))
302 #else
303 # define __attribute_alloc_align__(param) /* Ignore. */
304 #endif
305
306 /* At some point during the gcc 2.96 development the `pure' attribute
307 for functions was introduced. We don't want to use it unconditionally
308 (although this would be possible) since it generates warnings. */
309 #if __GNUC_PREREQ (2,96) || __glibc_has_attribute (__pure__)
310 # define __attribute_pure__ __attribute__ ((__pure__))
311 #else
312 # define __attribute_pure__ /* Ignore */
313 #endif
314
315 /* This declaration tells the compiler that the value is constant. */
316 #if __GNUC_PREREQ (2,5) || __glibc_has_attribute (__const__)
317 # define __attribute_const__ __attribute__ ((__const__))
318 #else
319 # define __attribute_const__ /* Ignore */
320 #endif
321
322 #if __GNUC_PREREQ (2,7) || __glibc_has_attribute (__unused__)
323 # define __attribute_maybe_unused__ __attribute__ ((__unused__))
324 #else
325 # define __attribute_maybe_unused__ /* Ignore */
326 #endif
327
328 /* At some point during the gcc 3.1 development the `used' attribute
329 for functions was introduced. We don't want to use it unconditionally
330 (although this would be possible) since it generates warnings. */
331 #if __GNUC_PREREQ (3,1) || __glibc_has_attribute (__used__)
332 # define __attribute_used__ __attribute__ ((__used__))
333 # define __attribute_noinline__ __attribute__ ((__noinline__))
334 #else
335 # define __attribute_used__ __attribute__ ((__unused__))
336 # define __attribute_noinline__ /* Ignore */
337 #endif
338
339 /* Since version 3.2, gcc allows marking deprecated functions. */
340 #if __GNUC_PREREQ (3,2) || __glibc_has_attribute (__deprecated__)
341 # define __attribute_deprecated__ __attribute__ ((__deprecated__))
342 #else
343 # define __attribute_deprecated__ /* Ignore */
344 #endif
345
346 /* Since version 4.5, gcc also allows one to specify the message printed
347 when a deprecated function is used. clang claims to be gcc 4.2, but
348 may also support this feature. */
349 #if __GNUC_PREREQ (4,5) \
350 || __glibc_has_extension (__attribute_deprecated_with_message__)
351 # define __attribute_deprecated_msg__(msg) \
352 __attribute__ ((__deprecated__ (msg)))
353 #else
354 # define __attribute_deprecated_msg__(msg) __attribute_deprecated__
355 #endif
356
357 /* At some point during the gcc 2.8 development the `format_arg' attribute
358 for functions was introduced. We don't want to use it unconditionally
359 (although this would be possible) since it generates warnings.
360 If several `format_arg' attributes are given for the same function, in
361 gcc-3.0 and older, all but the last one are ignored. In newer gccs,
362 all designated arguments are considered. */
363 #if __GNUC_PREREQ (2,8) || __glibc_has_attribute (__format_arg__)
364 # define __attribute_format_arg__(x) __attribute__ ((__format_arg__ (x)))
365 #else
366 # define __attribute_format_arg__(x) /* Ignore */
367 #endif
368
369 /* At some point during the gcc 2.97 development the `strfmon' format
370 attribute for functions was introduced. We don't want to use it
371 unconditionally (although this would be possible) since it
372 generates warnings. */
373 #if __GNUC_PREREQ (2,97) || __glibc_has_attribute (__format__)
374 # define __attribute_format_strfmon__(a,b) \
375 __attribute__ ((__format__ (__strfmon__, a, b)))
376 #else
377 # define __attribute_format_strfmon__(a,b) /* Ignore */
378 #endif
379
380 /* The nonnull function attribute marks pointer parameters that
381 must not be NULL. This has the name __nonnull in glibc,
382 and __attribute_nonnull__ in files shared with Gnulib to avoid
383 collision with a different __nonnull in DragonFlyBSD 5.9. */
384 #ifndef __attribute_nonnull__
385 # if __GNUC_PREREQ (3,3) || __glibc_has_attribute (__nonnull__)
386 # define __attribute_nonnull__(params) __attribute__ ((__nonnull__ params))
387 # else
388 # define __attribute_nonnull__(params)
389 # endif
390 #endif
391 #ifndef __nonnull
392 # define __nonnull(params) __attribute_nonnull__ (params)
393 #endif
394
395 /* The returns_nonnull function attribute marks the return type of the function
396 as always being non-null. */
397 #ifndef __returns_nonnull
398 # if __GNUC_PREREQ (4, 9) || __glibc_has_attribute (__returns_nonnull__)
399 # define __returns_nonnull __attribute__ ((__returns_nonnull__))
400 # else
401 # define __returns_nonnull
402 # endif
403 #endif
404
405 /* If fortification mode, we warn about unused results of certain
406 function calls which can lead to problems. */
407 #if __GNUC_PREREQ (3,4) || __glibc_has_attribute (__warn_unused_result__)
408 # define __attribute_warn_unused_result__ \
409 __attribute__ ((__warn_unused_result__))
410 # if defined __USE_FORTIFY_LEVEL && __USE_FORTIFY_LEVEL > 0
411 # define __wur __attribute_warn_unused_result__
412 # endif
413 #else
414 # define __attribute_warn_unused_result__ /* empty */
415 #endif
416 #ifndef __wur
417 # define __wur /* Ignore */
418 #endif
419
420 /* Forces a function to be always inlined. */
421 #if __GNUC_PREREQ (3,2) || __glibc_has_attribute (__always_inline__)
422 /* The Linux kernel defines __always_inline in stddef.h (283d7573), and
423 it conflicts with this definition. Therefore undefine it first to
424 allow either header to be included first. */
425 # undef __always_inline
426 # define __always_inline __inline __attribute__ ((__always_inline__))
427 #else
428 # undef __always_inline
429 # define __always_inline __inline
430 #endif
431
432 /* Associate error messages with the source location of the call site rather
433 than with the source location inside the function. */
434 #if __GNUC_PREREQ (4,3) || __glibc_has_attribute (__artificial__)
435 # define __attribute_artificial__ __attribute__ ((__artificial__))
436 #else
437 # define __attribute_artificial__ /* Ignore */
438 #endif
439
440 /* GCC 4.3 and above with -std=c99 or -std=gnu99 implements ISO C99
441 inline semantics, unless -fgnu89-inline is used. Using __GNUC_STDC_INLINE__
442 or __GNUC_GNU_INLINE is not a good enough check for gcc because gcc versions
443 older than 4.3 may define these macros and still not guarantee GNU inlining
444 semantics.
445
446 clang++ identifies itself as gcc-4.2, but has support for GNU inlining
447 semantics, that can be checked for by using the __GNUC_STDC_INLINE_ and
448 __GNUC_GNU_INLINE__ macro definitions. */
449 #if (!defined __cplusplus || __GNUC_PREREQ (4,3) \
450 || (defined __clang__ && (defined __GNUC_STDC_INLINE__ \
451 || defined __GNUC_GNU_INLINE__)))
452 # if defined __GNUC_STDC_INLINE__ || defined __cplusplus
453 # define __extern_inline extern __inline __attribute__ ((__gnu_inline__))
454 # define __extern_always_inline \
455 extern __always_inline __attribute__ ((__gnu_inline__))
456 # else
457 # define __extern_inline extern __inline
458 # define __extern_always_inline extern __always_inline
459 # endif
460 #endif
461
462 #ifdef __extern_always_inline
463 # define __fortify_function __extern_always_inline __attribute_artificial__
464 #endif
465
466 /* GCC 4.3 and above allow passing all anonymous arguments of an
467 __extern_always_inline function to some other vararg function. */
468 #if __GNUC_PREREQ (4,3)
469 # define __va_arg_pack() __builtin_va_arg_pack ()
470 # define __va_arg_pack_len() __builtin_va_arg_pack_len ()
471 #endif
472
473 /* It is possible to compile containing GCC extensions even if GCC is
474 run in pedantic mode if the uses are carefully marked using the
475 `__extension__' keyword. But this is not generally available before
476 version 2.8. */
477 #if !(__GNUC_PREREQ (2,8) || defined __clang__)
478 # define __extension__ /* Ignore */
479 #endif
480
481 /* __restrict is known in EGCS 1.2 and above, and in clang.
482 It works also in C++ mode (outside of arrays), but only when spelled
483 as '__restrict', not 'restrict'. */
484 #if !(__GNUC_PREREQ (2,92) || __clang_major__ >= 3)
485 # if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
486 # define __restrict restrict
487 # else
488 # define __restrict /* Ignore */
489 # endif
490 #endif
491
492 /* ISO C99 also allows to declare arrays as non-overlapping. The syntax is
493 array_name[restrict]
494 GCC 3.1 and clang support this.
495 This syntax is not usable in C++ mode. */
496 #if (__GNUC_PREREQ (3,1) || __clang_major__ >= 3) && !defined __cplusplus
497 # define __restrict_arr __restrict
498 #else
499 # ifdef __GNUC__
500 # define __restrict_arr /* Not supported in old GCC. */
501 # else
502 # if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
503 # define __restrict_arr restrict
504 # else
505 /* Some other non-C99 compiler. */
506 # define __restrict_arr /* Not supported. */
507 # endif
508 # endif
509 #endif
510
511 #if (__GNUC__ >= 3) || __glibc_has_builtin (__builtin_expect)
512 # define __glibc_unlikely(cond) __builtin_expect ((cond), 0)
513 # define __glibc_likely(cond) __builtin_expect ((cond), 1)
514 #else
515 # define __glibc_unlikely(cond) (cond)
516 # define __glibc_likely(cond) (cond)
517 #endif
518
519 #if (!defined _Noreturn \
520 && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \
521 && !(__GNUC_PREREQ (4,7) \
522 || (3 < __clang_major__ + (5 <= __clang_minor__))))
523 # if __GNUC_PREREQ (2,8)
524 # define _Noreturn __attribute__ ((__noreturn__))
525 # else
526 # define _Noreturn
527 # endif
528 #endif
529
530 #if __GNUC_PREREQ (8, 0)
531 /* Describes a char array whose address can safely be passed as the first
532 argument to strncpy and strncat, as the char array is not necessarily
533 a NUL-terminated string. */
534 # define __attribute_nonstring__ __attribute__ ((__nonstring__))
535 #else
536 # define __attribute_nonstring__
537 #endif
538
539 /* Undefine (also defined in libc-symbols.h). */
540 #undef __attribute_copy__
541 #if __GNUC_PREREQ (9, 0)
542 /* Copies attributes from the declaration or type referenced by
543 the argument. */
544 # define __attribute_copy__(arg) __attribute__ ((__copy__ (arg)))
545 #else
546 # define __attribute_copy__(arg)
547 #endif
548
549 #if (!defined _Static_assert && !defined __cplusplus \
550 && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \
551 && (!(__GNUC_PREREQ (4, 6) || __clang_major__ >= 4) \
552 || defined __STRICT_ANSI__))
553 # define _Static_assert(expr, diagnostic) \
554 extern int (*__Static_assert_function (void)) \
555 [!!sizeof (struct { int __error_if_negative: (expr) ? 2 : -1; })]
556 #endif
557
558 /* Gnulib avoids including these, as they don't work on non-glibc or
559 older glibc platforms. */
560 #ifndef __GNULIB_CDEFS
561 # include <bits/wordsize.h>
562 # include <bits/long-double.h>
563 #endif
564
565 #if __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 1
566 # ifdef __REDIRECT
567
568 /* Alias name defined automatically. */
569 # define __LDBL_REDIR(name, proto) ... unused__ldbl_redir
570 # define __LDBL_REDIR_DECL(name) \
571 extern __typeof (name) name __asm (__ASMNAME ("__" #name "ieee128"));
572
573 /* Alias name defined automatically, with leading underscores. */
574 # define __LDBL_REDIR2_DECL(name) \
575 extern __typeof (__##name) __##name \
576 __asm (__ASMNAME ("__" #name "ieee128"));
577
578 /* Alias name defined manually. */
579 # define __LDBL_REDIR1(name, proto, alias) ... unused__ldbl_redir1
580 # define __LDBL_REDIR1_DECL(name, alias) \
581 extern __typeof (name) name __asm (__ASMNAME (#alias));
582
583 # define __LDBL_REDIR1_NTH(name, proto, alias) \
584 __REDIRECT_NTH (name, proto, alias)
585 # define __REDIRECT_NTH_LDBL(name, proto, alias) \
586 __LDBL_REDIR1_NTH (name, proto, __##alias##ieee128)
587
588 /* Unused. */
589 # define __REDIRECT_LDBL(name, proto, alias) ... unused__redirect_ldbl
590 # define __LDBL_REDIR_NTH(name, proto) ... unused__ldbl_redir_nth
591
592 # else
593 _Static_assert (0, "IEEE 128-bits long double requires redirection on this platform");
594 # endif
595 #elif defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
596 # define __LDBL_COMPAT 1
597 # ifdef __REDIRECT
598 # define __LDBL_REDIR1(name, proto, alias) __REDIRECT (name, proto, alias)
599 # define __LDBL_REDIR(name, proto) \
600 __LDBL_REDIR1 (name, proto, __nldbl_##name)
601 # define __LDBL_REDIR1_NTH(name, proto, alias) __REDIRECT_NTH (name, proto, alias)
602 # define __LDBL_REDIR_NTH(name, proto) \
603 __LDBL_REDIR1_NTH (name, proto, __nldbl_##name)
604 # define __LDBL_REDIR2_DECL(name) \
605 extern __typeof (__##name) __##name __asm (__ASMNAME ("__nldbl___" #name));
606 # define __LDBL_REDIR1_DECL(name, alias) \
607 extern __typeof (name) name __asm (__ASMNAME (#alias));
608 # define __LDBL_REDIR_DECL(name) \
609 extern __typeof (name) name __asm (__ASMNAME ("__nldbl_" #name));
610 # define __REDIRECT_LDBL(name, proto, alias) \
611 __LDBL_REDIR1 (name, proto, __nldbl_##alias)
612 # define __REDIRECT_NTH_LDBL(name, proto, alias) \
613 __LDBL_REDIR1_NTH (name, proto, __nldbl_##alias)
614 # endif
615 #endif
616 #if (!defined __LDBL_COMPAT && __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 0) \
617 || !defined __REDIRECT
618 # define __LDBL_REDIR1(name, proto, alias) name proto
619 # define __LDBL_REDIR(name, proto) name proto
620 # define __LDBL_REDIR1_NTH(name, proto, alias) name proto __THROW
621 # define __LDBL_REDIR_NTH(name, proto) name proto __THROW
622 # define __LDBL_REDIR2_DECL(name)
623 # define __LDBL_REDIR_DECL(name)
624 # ifdef __REDIRECT
625 # define __REDIRECT_LDBL(name, proto, alias) __REDIRECT (name, proto, alias)
626 # define __REDIRECT_NTH_LDBL(name, proto, alias) \
627 __REDIRECT_NTH (name, proto, alias)
628 # endif
629 #endif
630
631 /* __glibc_macro_warning (MESSAGE) issues warning MESSAGE. This is
632 intended for use in preprocessor macros.
633
634 Note: MESSAGE must be a _single_ string; concatenation of string
635 literals is not supported. */
636 #if __GNUC_PREREQ (4,8) || __glibc_clang_prereq (3,5)
637 # define __glibc_macro_warning1(message) _Pragma (#message)
638 # define __glibc_macro_warning(message) \
639 __glibc_macro_warning1 (GCC warning message)
640 #else
641 # define __glibc_macro_warning(msg)
642 #endif
643
644 /* Generic selection (ISO C11) is a C-only feature, available in GCC
645 since version 4.9. Previous versions do not provide generic
646 selection, even though they might set __STDC_VERSION__ to 201112L,
647 when in -std=c11 mode. Thus, we must check for !defined __GNUC__
648 when testing __STDC_VERSION__ for generic selection support.
649 On the other hand, Clang also defines __GNUC__, so a clang-specific
650 check is required to enable the use of generic selection. */
651 #if !defined __cplusplus \
652 && (__GNUC_PREREQ (4, 9) \
653 || __glibc_has_extension (c_generic_selections) \
654 || (!defined __GNUC__ && defined __STDC_VERSION__ \
655 && __STDC_VERSION__ >= 201112L))
656 # define __HAVE_GENERIC_SELECTION 1
657 #else
658 # define __HAVE_GENERIC_SELECTION 0
659 #endif
660
661 #if __GNUC_PREREQ (10, 0)
662 /* Designates a 1-based positional argument ref-index of pointer type
663 that can be used to access size-index elements of the pointed-to
664 array according to access mode, or at least one element when
665 size-index is not provided:
666 access (access-mode, <ref-index> [, <size-index>]) */
667 # define __attr_access(x) __attribute__ ((__access__ x))
668 /* For _FORTIFY_SOURCE == 3 we use __builtin_dynamic_object_size, which may
669 use the access attribute to get object sizes from function definition
670 arguments, so we can't use them on functions we fortify. Drop the object
671 size hints for such functions. */
672 # if __USE_FORTIFY_LEVEL == 3
673 # define __fortified_attr_access(a, o, s) __attribute__ ((__access__ (a, o)))
674 # else
675 # define __fortified_attr_access(a, o, s) __attr_access ((a, o, s))
676 # endif
677 # if __GNUC_PREREQ (11, 0)
678 # define __attr_access_none(argno) __attribute__ ((__access__ (__none__, argno)))
679 # else
680 # define __attr_access_none(argno)
681 # endif
682 #else
683 # define __fortified_attr_access(a, o, s)
684 # define __attr_access(x)
685 # define __attr_access_none(argno)
686 #endif
687
688 #if __GNUC_PREREQ (11, 0)
689 /* Designates dealloc as a function to call to deallocate objects
690 allocated by the declared function. */
691 # define __attr_dealloc(dealloc, argno) \
692 __attribute__ ((__malloc__ (dealloc, argno)))
693 # define __attr_dealloc_free __attr_dealloc (__builtin_free, 1)
694 #else
695 # define __attr_dealloc(dealloc, argno)
696 # define __attr_dealloc_free
697 #endif
698
699 /* Specify that a function such as setjmp or vfork may return
700 twice. */
701 #if __GNUC_PREREQ (4, 1)
702 # define __attribute_returns_twice__ __attribute__ ((__returns_twice__))
703 #else
704 # define __attribute_returns_twice__ /* Ignore. */
705 #endif
706
707 #endif /* sys/cdefs.h */