cdefs.h: Define __COLD
[glibc.git] / misc / sys / cdefs.h
blob9a07e297a6c250acf89ee240f76d49250cd6f575
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.
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.
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.
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/>. */
19 #ifndef _SYS_CDEFS_H
20 #define _SYS_CDEFS_H 1
22 /* We are almost always included from features.h. */
23 #ifndef _FEATURES_H
24 # include <features.h>
25 #endif
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__ && !defined __cplusplus
31 # error "You need a ISO C or C++ conforming compiler to use the glibc headers"
32 #endif
34 /* Some user header file might have defined this before. */
35 #undef __P
36 #undef __PMT
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 || 3 < __clang_major__ + (5 <= __clang_minor__)))
45 # define __glibc_has_attribute(attr) __has_attribute (attr)
46 #else
47 # define __glibc_has_attribute(attr) 0
48 #endif
49 #ifdef __has_builtin
50 # define __glibc_has_builtin(name) __has_builtin (name)
51 #else
52 # define __glibc_has_builtin(name) 0
53 #endif
54 #ifdef __has_extension
55 # define __glibc_has_extension(ext) __has_extension (ext)
56 #else
57 # define __glibc_has_extension(ext) 0
58 #endif
60 #if defined __GNUC__ || defined __clang__
62 /* All functions, except those with callbacks or those that
63 synchronize memory, are leaf functions. */
64 # if __GNUC_PREREQ (4, 6) && !defined _LIBC
65 # define __LEAF , __leaf__
66 # define __LEAF_ATTR __attribute__ ((__leaf__))
67 # else
68 # define __LEAF
69 # define __LEAF_ATTR
70 # endif
72 /* GCC can always grok prototypes. For C++ programs we add throw()
73 to help it optimize the function calls. But this only works with
74 gcc 2.8.x and egcs. For gcc 3.4 and up we even mark C functions
75 as non-throwing using a function attribute since programs can use
76 the -fexceptions options for C code as well. */
77 # if !defined __cplusplus \
78 && (__GNUC_PREREQ (3, 4) || __glibc_has_attribute (__nothrow__))
79 # define __THROW __attribute__ ((__nothrow__ __LEAF))
80 # define __THROWNL __attribute__ ((__nothrow__))
81 # define __NTH(fct) __attribute__ ((__nothrow__ __LEAF)) fct
82 # define __NTHNL(fct) __attribute__ ((__nothrow__)) fct
83 # else
84 # if defined __cplusplus && (__GNUC_PREREQ (2,8) || __clang_major__ >= 4)
85 # if __cplusplus >= 201103L
86 # define __THROW noexcept (true)
87 # else
88 # define __THROW throw ()
89 # endif
90 # define __THROWNL __THROW
91 # define __NTH(fct) __LEAF_ATTR fct __THROW
92 # define __NTHNL(fct) fct __THROW
93 # else
94 # define __THROW
95 # define __THROWNL
96 # define __NTH(fct) fct
97 # define __NTHNL(fct) fct
98 # endif
99 # endif
101 # if __GNUC_PREREQ (4, 3) || __glibc_has_attribute (__cold__)
102 # define __COLD __attribute__ ((__cold__))
103 # else
104 # define __COLD
105 # endif
107 #else /* Not GCC or clang. */
109 # if (defined __cplusplus \
110 || (defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L))
111 # define __inline inline
112 # else
113 # define __inline /* No inline functions. */
114 # endif
116 # define __THROW
117 # define __THROWNL
118 # define __NTH(fct) fct
119 # define __COLD
121 #endif /* GCC || clang. */
123 /* These two macros are not used in glibc anymore. They are kept here
124 only because some other projects expect the macros to be defined. */
125 #define __P(args) args
126 #define __PMT(args) args
128 /* For these things, GCC behaves the ANSI way normally,
129 and the non-ANSI way under -traditional. */
131 #define __CONCAT(x,y) x ## y
132 #define __STRING(x) #x
134 /* This is not a typedef so `const __ptr_t' does the right thing. */
135 #define __ptr_t void *
138 /* C++ needs to know that types and declarations are C, not C++. */
139 #ifdef __cplusplus
140 # define __BEGIN_DECLS extern "C" {
141 # define __END_DECLS }
142 #else
143 # define __BEGIN_DECLS
144 # define __END_DECLS
145 #endif
148 /* Fortify support. */
149 #define __bos(ptr) __builtin_object_size (ptr, __USE_FORTIFY_LEVEL > 1)
150 #define __bos0(ptr) __builtin_object_size (ptr, 0)
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
162 #if __USE_FORTIFY_LEVEL > 0
163 /* Compile time conditions to choose between the regular, _chk and _chk_warn
164 variants. These conditions should get evaluated to constant and optimized
165 away. */
167 #define __glibc_safe_len_cond(__l, __s, __osz) ((__l) <= (__osz) / (__s))
168 #define __glibc_unsigned_or_positive(__l) \
169 ((__typeof (__l)) 0 < (__typeof (__l)) -1 \
170 || (__builtin_constant_p (__l) && (__l) > 0))
172 /* Length is known to be safe at compile time if the __L * __S <= __OBJSZ
173 condition can be folded to a constant and if it is true, or unknown (-1) */
174 #define __glibc_safe_or_unknown_len(__l, __s, __osz) \
175 ((__builtin_constant_p (__osz) && (__osz) == (__SIZE_TYPE__) -1) \
176 || (__glibc_unsigned_or_positive (__l) \
177 && __builtin_constant_p (__glibc_safe_len_cond ((__SIZE_TYPE__) (__l), \
178 (__s), (__osz))) \
179 && __glibc_safe_len_cond ((__SIZE_TYPE__) (__l), (__s), (__osz))))
181 /* Conversely, we know at compile time that the length is unsafe if the
182 __L * __S <= __OBJSZ condition can be folded to a constant and if it is
183 false. */
184 #define __glibc_unsafe_len(__l, __s, __osz) \
185 (__glibc_unsigned_or_positive (__l) \
186 && __builtin_constant_p (__glibc_safe_len_cond ((__SIZE_TYPE__) (__l), \
187 __s, __osz)) \
188 && !__glibc_safe_len_cond ((__SIZE_TYPE__) (__l), __s, __osz))
190 /* Fortify function f. __f_alias, __f_chk and __f_chk_warn must be
191 declared. */
193 #define __glibc_fortify(f, __l, __s, __osz, ...) \
194 (__glibc_safe_or_unknown_len (__l, __s, __osz) \
195 ? __ ## f ## _alias (__VA_ARGS__) \
196 : (__glibc_unsafe_len (__l, __s, __osz) \
197 ? __ ## f ## _chk_warn (__VA_ARGS__, __osz) \
198 : __ ## f ## _chk (__VA_ARGS__, __osz)))
200 /* Fortify function f, where object size argument passed to f is the number of
201 elements and not total size. */
203 #define __glibc_fortify_n(f, __l, __s, __osz, ...) \
204 (__glibc_safe_or_unknown_len (__l, __s, __osz) \
205 ? __ ## f ## _alias (__VA_ARGS__) \
206 : (__glibc_unsafe_len (__l, __s, __osz) \
207 ? __ ## f ## _chk_warn (__VA_ARGS__, (__osz) / (__s)) \
208 : __ ## f ## _chk (__VA_ARGS__, (__osz) / (__s))))
209 #endif
211 #if __GNUC_PREREQ (4,3)
212 # define __warnattr(msg) __attribute__((__warning__ (msg)))
213 # define __errordecl(name, msg) \
214 extern void name (void) __attribute__((__error__ (msg)))
215 #else
216 # define __warnattr(msg)
217 # define __errordecl(name, msg) extern void name (void)
218 #endif
220 /* Support for flexible arrays.
221 Headers that should use flexible arrays only if they're "real"
222 (e.g. only if they won't affect sizeof()) should test
223 #if __glibc_c99_flexarr_available. */
224 #if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L && !defined __HP_cc
225 # define __flexarr []
226 # define __glibc_c99_flexarr_available 1
227 #elif __GNUC_PREREQ (2,97) || defined __clang__
228 /* GCC 2.97 and clang support C99 flexible array members as an extension,
229 even when in C89 mode or compiling C++ (any version). */
230 # define __flexarr []
231 # define __glibc_c99_flexarr_available 1
232 #elif defined __GNUC__
233 /* Pre-2.97 GCC did not support C99 flexible arrays but did have
234 an equivalent extension with slightly different notation. */
235 # define __flexarr [0]
236 # define __glibc_c99_flexarr_available 1
237 #else
238 /* Some other non-C99 compiler. Approximate with [1]. */
239 # define __flexarr [1]
240 # define __glibc_c99_flexarr_available 0
241 #endif
244 /* __asm__ ("xyz") is used throughout the headers to rename functions
245 at the assembly language level. This is wrapped by the __REDIRECT
246 macro, in order to support compilers that can do this some other
247 way. When compilers don't support asm-names at all, we have to do
248 preprocessor tricks instead (which don't have exactly the right
249 semantics, but it's the best we can do).
251 Example:
252 int __REDIRECT(setpgrp, (__pid_t pid, __pid_t pgrp), setpgid); */
254 #if (defined __GNUC__ && __GNUC__ >= 2) || (__clang_major__ >= 4)
256 # define __REDIRECT(name, proto, alias) name proto __asm__ (__ASMNAME (#alias))
257 # ifdef __cplusplus
258 # define __REDIRECT_NTH(name, proto, alias) \
259 name proto __THROW __asm__ (__ASMNAME (#alias))
260 # define __REDIRECT_NTHNL(name, proto, alias) \
261 name proto __THROWNL __asm__ (__ASMNAME (#alias))
262 # else
263 # define __REDIRECT_NTH(name, proto, alias) \
264 name proto __asm__ (__ASMNAME (#alias)) __THROW
265 # define __REDIRECT_NTHNL(name, proto, alias) \
266 name proto __asm__ (__ASMNAME (#alias)) __THROWNL
267 # endif
268 # define __ASMNAME(cname) __ASMNAME2 (__USER_LABEL_PREFIX__, cname)
269 # define __ASMNAME2(prefix, cname) __STRING (prefix) cname
272 #elif __SOME_OTHER_COMPILER__
274 # define __REDIRECT(name, proto, alias) name proto; \
275 _Pragma("let " #name " = " #alias)
277 #endif
279 /* GCC and clang have various useful declarations that can be made with
280 the '__attribute__' syntax. All of the ways we use this do fine if
281 they are omitted for compilers that don't understand it. */
282 #if !(defined __GNUC__ || defined __clang__)
283 # define __attribute__(xyz) /* Ignore */
284 #endif
286 /* At some point during the gcc 2.96 development the `malloc' attribute
287 for functions was introduced. We don't want to use it unconditionally
288 (although this would be possible) since it generates warnings. */
289 #if __GNUC_PREREQ (2,96) || __glibc_has_attribute (__malloc__)
290 # define __attribute_malloc__ __attribute__ ((__malloc__))
291 #else
292 # define __attribute_malloc__ /* Ignore */
293 #endif
295 /* Tell the compiler which arguments to an allocation function
296 indicate the size of the allocation. */
297 #if __GNUC_PREREQ (4, 3)
298 # define __attribute_alloc_size__(params) \
299 __attribute__ ((__alloc_size__ params))
300 #else
301 # define __attribute_alloc_size__(params) /* Ignore. */
302 #endif
304 /* Tell the compiler which argument to an allocation function
305 indicates the alignment of the allocation. */
306 #if __GNUC_PREREQ (4, 9) || __glibc_has_attribute (__alloc_align__)
307 # define __attribute_alloc_align__(param) \
308 __attribute__ ((__alloc_align__ param))
309 #else
310 # define __attribute_alloc_align__(param) /* Ignore. */
311 #endif
313 /* At some point during the gcc 2.96 development the `pure' attribute
314 for functions was introduced. We don't want to use it unconditionally
315 (although this would be possible) since it generates warnings. */
316 #if __GNUC_PREREQ (2,96) || __glibc_has_attribute (__pure__)
317 # define __attribute_pure__ __attribute__ ((__pure__))
318 #else
319 # define __attribute_pure__ /* Ignore */
320 #endif
322 /* This declaration tells the compiler that the value is constant. */
323 #if __GNUC_PREREQ (2,5) || __glibc_has_attribute (__const__)
324 # define __attribute_const__ __attribute__ ((__const__))
325 #else
326 # define __attribute_const__ /* Ignore */
327 #endif
329 #if __GNUC_PREREQ (2,7) || __glibc_has_attribute (__unused__)
330 # define __attribute_maybe_unused__ __attribute__ ((__unused__))
331 #else
332 # define __attribute_maybe_unused__ /* Ignore */
333 #endif
335 /* At some point during the gcc 3.1 development the `used' attribute
336 for functions was introduced. We don't want to use it unconditionally
337 (although this would be possible) since it generates warnings. */
338 #if __GNUC_PREREQ (3,1) || __glibc_has_attribute (__used__)
339 # define __attribute_used__ __attribute__ ((__used__))
340 # define __attribute_noinline__ __attribute__ ((__noinline__))
341 #else
342 # define __attribute_used__ __attribute__ ((__unused__))
343 # define __attribute_noinline__ /* Ignore */
344 #endif
346 /* Since version 3.2, gcc allows marking deprecated functions. */
347 #if __GNUC_PREREQ (3,2) || __glibc_has_attribute (__deprecated__)
348 # define __attribute_deprecated__ __attribute__ ((__deprecated__))
349 #else
350 # define __attribute_deprecated__ /* Ignore */
351 #endif
353 /* Since version 4.5, gcc also allows one to specify the message printed
354 when a deprecated function is used. clang claims to be gcc 4.2, but
355 may also support this feature. */
356 #if __GNUC_PREREQ (4,5) \
357 || __glibc_has_extension (__attribute_deprecated_with_message__)
358 # define __attribute_deprecated_msg__(msg) \
359 __attribute__ ((__deprecated__ (msg)))
360 #else
361 # define __attribute_deprecated_msg__(msg) __attribute_deprecated__
362 #endif
364 /* At some point during the gcc 2.8 development the `format_arg' attribute
365 for functions was introduced. We don't want to use it unconditionally
366 (although this would be possible) since it generates warnings.
367 If several `format_arg' attributes are given for the same function, in
368 gcc-3.0 and older, all but the last one are ignored. In newer gccs,
369 all designated arguments are considered. */
370 #if __GNUC_PREREQ (2,8) || __glibc_has_attribute (__format_arg__)
371 # define __attribute_format_arg__(x) __attribute__ ((__format_arg__ (x)))
372 #else
373 # define __attribute_format_arg__(x) /* Ignore */
374 #endif
376 /* At some point during the gcc 2.97 development the `strfmon' format
377 attribute for functions was introduced. We don't want to use it
378 unconditionally (although this would be possible) since it
379 generates warnings. */
380 #if __GNUC_PREREQ (2,97) || __glibc_has_attribute (__format__)
381 # define __attribute_format_strfmon__(a,b) \
382 __attribute__ ((__format__ (__strfmon__, a, b)))
383 #else
384 # define __attribute_format_strfmon__(a,b) /* Ignore */
385 #endif
387 /* The nonnull function attribute marks pointer parameters that
388 must not be NULL. This has the name __nonnull in glibc,
389 and __attribute_nonnull__ in files shared with Gnulib to avoid
390 collision with a different __nonnull in DragonFlyBSD 5.9. */
391 #ifndef __attribute_nonnull__
392 # if __GNUC_PREREQ (3,3) || __glibc_has_attribute (__nonnull__)
393 # define __attribute_nonnull__(params) __attribute__ ((__nonnull__ params))
394 # else
395 # define __attribute_nonnull__(params)
396 # endif
397 #endif
398 #ifndef __nonnull
399 # define __nonnull(params) __attribute_nonnull__ (params)
400 #endif
402 /* The returns_nonnull function attribute marks the return type of the function
403 as always being non-null. */
404 #ifndef __returns_nonnull
405 # if __GNUC_PREREQ (4, 9) || __glibc_has_attribute (__returns_nonnull__)
406 # define __returns_nonnull __attribute__ ((__returns_nonnull__))
407 # else
408 # define __returns_nonnull
409 # endif
410 #endif
412 /* If fortification mode, we warn about unused results of certain
413 function calls which can lead to problems. */
414 #if __GNUC_PREREQ (3,4) || __glibc_has_attribute (__warn_unused_result__)
415 # define __attribute_warn_unused_result__ \
416 __attribute__ ((__warn_unused_result__))
417 # if defined __USE_FORTIFY_LEVEL && __USE_FORTIFY_LEVEL > 0
418 # define __wur __attribute_warn_unused_result__
419 # endif
420 #else
421 # define __attribute_warn_unused_result__ /* empty */
422 #endif
423 #ifndef __wur
424 # define __wur /* Ignore */
425 #endif
427 /* Forces a function to be always inlined. */
428 #if __GNUC_PREREQ (3,2) || __glibc_has_attribute (__always_inline__)
429 /* The Linux kernel defines __always_inline in stddef.h (283d7573), and
430 it conflicts with this definition. Therefore undefine it first to
431 allow either header to be included first. */
432 # undef __always_inline
433 # define __always_inline __inline __attribute__ ((__always_inline__))
434 #else
435 # undef __always_inline
436 # define __always_inline __inline
437 #endif
439 /* Associate error messages with the source location of the call site rather
440 than with the source location inside the function. */
441 #if __GNUC_PREREQ (4,3) || __glibc_has_attribute (__artificial__)
442 # define __attribute_artificial__ __attribute__ ((__artificial__))
443 #else
444 # define __attribute_artificial__ /* Ignore */
445 #endif
447 /* GCC 4.3 and above with -std=c99 or -std=gnu99 implements ISO C99
448 inline semantics, unless -fgnu89-inline is used. Using __GNUC_STDC_INLINE__
449 or __GNUC_GNU_INLINE is not a good enough check for gcc because gcc versions
450 older than 4.3 may define these macros and still not guarantee GNU inlining
451 semantics.
453 clang++ identifies itself as gcc-4.2, but has support for GNU inlining
454 semantics, that can be checked for by using the __GNUC_STDC_INLINE_ and
455 __GNUC_GNU_INLINE__ macro definitions. */
456 #if (!defined __cplusplus || __GNUC_PREREQ (4,3) \
457 || (defined __clang__ && (defined __GNUC_STDC_INLINE__ \
458 || defined __GNUC_GNU_INLINE__)))
459 # if defined __GNUC_STDC_INLINE__ || defined __cplusplus
460 # define __extern_inline extern __inline __attribute__ ((__gnu_inline__))
461 # define __extern_always_inline \
462 extern __always_inline __attribute__ ((__gnu_inline__))
463 # else
464 # define __extern_inline extern __inline
465 # define __extern_always_inline extern __always_inline
466 # endif
467 #endif
469 #ifdef __extern_always_inline
470 # define __fortify_function __extern_always_inline __attribute_artificial__
471 #endif
473 /* GCC 4.3 and above allow passing all anonymous arguments of an
474 __extern_always_inline function to some other vararg function. */
475 #if __GNUC_PREREQ (4,3)
476 # define __va_arg_pack() __builtin_va_arg_pack ()
477 # define __va_arg_pack_len() __builtin_va_arg_pack_len ()
478 #endif
480 /* It is possible to compile containing GCC extensions even if GCC is
481 run in pedantic mode if the uses are carefully marked using the
482 `__extension__' keyword. But this is not generally available before
483 version 2.8. */
484 #if !(__GNUC_PREREQ (2,8) || defined __clang__)
485 # define __extension__ /* Ignore */
486 #endif
488 /* __restrict is known in EGCS 1.2 and above, and in clang.
489 It works also in C++ mode (outside of arrays), but only when spelled
490 as '__restrict', not 'restrict'. */
491 #if !(__GNUC_PREREQ (2,92) || __clang_major__ >= 3)
492 # if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
493 # define __restrict restrict
494 # else
495 # define __restrict /* Ignore */
496 # endif
497 #endif
499 /* ISO C99 also allows to declare arrays as non-overlapping. The syntax is
500 array_name[restrict]
501 GCC 3.1 and clang support this.
502 This syntax is not usable in C++ mode. */
503 #if (__GNUC_PREREQ (3,1) || __clang_major__ >= 3) && !defined __cplusplus
504 # define __restrict_arr __restrict
505 #else
506 # ifdef __GNUC__
507 # define __restrict_arr /* Not supported in old GCC. */
508 # else
509 # if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
510 # define __restrict_arr restrict
511 # else
512 /* Some other non-C99 compiler. */
513 # define __restrict_arr /* Not supported. */
514 # endif
515 # endif
516 #endif
518 #if (__GNUC__ >= 3) || __glibc_has_builtin (__builtin_expect)
519 # define __glibc_unlikely(cond) __builtin_expect ((cond), 0)
520 # define __glibc_likely(cond) __builtin_expect ((cond), 1)
521 #else
522 # define __glibc_unlikely(cond) (cond)
523 # define __glibc_likely(cond) (cond)
524 #endif
526 #if (!defined _Noreturn \
527 && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \
528 && !(__GNUC_PREREQ (4,7) \
529 || (3 < __clang_major__ + (5 <= __clang_minor__))))
530 # if __GNUC_PREREQ (2,8)
531 # define _Noreturn __attribute__ ((__noreturn__))
532 # else
533 # define _Noreturn
534 # endif
535 #endif
537 #if __GNUC_PREREQ (8, 0)
538 /* Describes a char array whose address can safely be passed as the first
539 argument to strncpy and strncat, as the char array is not necessarily
540 a NUL-terminated string. */
541 # define __attribute_nonstring__ __attribute__ ((__nonstring__))
542 #else
543 # define __attribute_nonstring__
544 #endif
546 /* Undefine (also defined in libc-symbols.h). */
547 #undef __attribute_copy__
548 #if __GNUC_PREREQ (9, 0)
549 /* Copies attributes from the declaration or type referenced by
550 the argument. */
551 # define __attribute_copy__(arg) __attribute__ ((__copy__ (arg)))
552 #else
553 # define __attribute_copy__(arg)
554 #endif
556 #if (!defined _Static_assert && !defined __cplusplus \
557 && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \
558 && (!(__GNUC_PREREQ (4, 6) || __clang_major__ >= 4) \
559 || defined __STRICT_ANSI__))
560 # define _Static_assert(expr, diagnostic) \
561 extern int (*__Static_assert_function (void)) \
562 [!!sizeof (struct { int __error_if_negative: (expr) ? 2 : -1; })]
563 #endif
565 /* Gnulib avoids including these, as they don't work on non-glibc or
566 older glibc platforms. */
567 #ifndef __GNULIB_CDEFS
568 # include <bits/wordsize.h>
569 # include <bits/long-double.h>
570 #endif
572 #if __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 1
573 # ifdef __REDIRECT
575 /* Alias name defined automatically. */
576 # define __LDBL_REDIR(name, proto) ... unused__ldbl_redir
577 # define __LDBL_REDIR_DECL(name) \
578 extern __typeof (name) name __asm (__ASMNAME ("__" #name "ieee128"));
580 /* Alias name defined automatically, with leading underscores. */
581 # define __LDBL_REDIR2_DECL(name) \
582 extern __typeof (__##name) __##name \
583 __asm (__ASMNAME ("__" #name "ieee128"));
585 /* Alias name defined manually. */
586 # define __LDBL_REDIR1(name, proto, alias) ... unused__ldbl_redir1
587 # define __LDBL_REDIR1_DECL(name, alias) \
588 extern __typeof (name) name __asm (__ASMNAME (#alias));
590 # define __LDBL_REDIR1_NTH(name, proto, alias) \
591 __REDIRECT_NTH (name, proto, alias)
592 # define __REDIRECT_NTH_LDBL(name, proto, alias) \
593 __LDBL_REDIR1_NTH (name, proto, __##alias##ieee128)
595 /* Unused. */
596 # define __REDIRECT_LDBL(name, proto, alias) ... unused__redirect_ldbl
597 # define __LDBL_REDIR_NTH(name, proto) ... unused__ldbl_redir_nth
599 # else
600 _Static_assert (0, "IEEE 128-bits long double requires redirection on this platform");
601 # endif
602 #elif defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
603 # define __LDBL_COMPAT 1
604 # ifdef __REDIRECT
605 # define __LDBL_REDIR1(name, proto, alias) __REDIRECT (name, proto, alias)
606 # define __LDBL_REDIR(name, proto) \
607 __LDBL_REDIR1 (name, proto, __nldbl_##name)
608 # define __LDBL_REDIR1_NTH(name, proto, alias) __REDIRECT_NTH (name, proto, alias)
609 # define __LDBL_REDIR_NTH(name, proto) \
610 __LDBL_REDIR1_NTH (name, proto, __nldbl_##name)
611 # define __LDBL_REDIR2_DECL(name) \
612 extern __typeof (__##name) __##name __asm (__ASMNAME ("__nldbl___" #name));
613 # define __LDBL_REDIR1_DECL(name, alias) \
614 extern __typeof (name) name __asm (__ASMNAME (#alias));
615 # define __LDBL_REDIR_DECL(name) \
616 extern __typeof (name) name __asm (__ASMNAME ("__nldbl_" #name));
617 # define __REDIRECT_LDBL(name, proto, alias) \
618 __LDBL_REDIR1 (name, proto, __nldbl_##alias)
619 # define __REDIRECT_NTH_LDBL(name, proto, alias) \
620 __LDBL_REDIR1_NTH (name, proto, __nldbl_##alias)
621 # endif
622 #endif
623 #if (!defined __LDBL_COMPAT && __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 0) \
624 || !defined __REDIRECT
625 # define __LDBL_REDIR1(name, proto, alias) name proto
626 # define __LDBL_REDIR(name, proto) name proto
627 # define __LDBL_REDIR1_NTH(name, proto, alias) name proto __THROW
628 # define __LDBL_REDIR_NTH(name, proto) name proto __THROW
629 # define __LDBL_REDIR2_DECL(name)
630 # define __LDBL_REDIR_DECL(name)
631 # ifdef __REDIRECT
632 # define __REDIRECT_LDBL(name, proto, alias) __REDIRECT (name, proto, alias)
633 # define __REDIRECT_NTH_LDBL(name, proto, alias) \
634 __REDIRECT_NTH (name, proto, alias)
635 # endif
636 #endif
638 /* __glibc_macro_warning (MESSAGE) issues warning MESSAGE. This is
639 intended for use in preprocessor macros.
641 Note: MESSAGE must be a _single_ string; concatenation of string
642 literals is not supported. */
643 #if __GNUC_PREREQ (4,8) || __glibc_clang_prereq (3,5)
644 # define __glibc_macro_warning1(message) _Pragma (#message)
645 # define __glibc_macro_warning(message) \
646 __glibc_macro_warning1 (GCC warning message)
647 #else
648 # define __glibc_macro_warning(msg)
649 #endif
651 /* Generic selection (ISO C11) is a C-only feature, available in GCC
652 since version 4.9. Previous versions do not provide generic
653 selection, even though they might set __STDC_VERSION__ to 201112L,
654 when in -std=c11 mode. Thus, we must check for !defined __GNUC__
655 when testing __STDC_VERSION__ for generic selection support.
656 On the other hand, Clang also defines __GNUC__, so a clang-specific
657 check is required to enable the use of generic selection. */
658 #if !defined __cplusplus \
659 && (__GNUC_PREREQ (4, 9) \
660 || __glibc_has_extension (c_generic_selections) \
661 || (!defined __GNUC__ && defined __STDC_VERSION__ \
662 && __STDC_VERSION__ >= 201112L))
663 # define __HAVE_GENERIC_SELECTION 1
664 #else
665 # define __HAVE_GENERIC_SELECTION 0
666 #endif
668 #if __GNUC_PREREQ (10, 0)
669 /* Designates a 1-based positional argument ref-index of pointer type
670 that can be used to access size-index elements of the pointed-to
671 array according to access mode, or at least one element when
672 size-index is not provided:
673 access (access-mode, <ref-index> [, <size-index>]) */
674 # define __attr_access(x) __attribute__ ((__access__ x))
675 /* For _FORTIFY_SOURCE == 3 we use __builtin_dynamic_object_size, which may
676 use the access attribute to get object sizes from function definition
677 arguments, so we can't use them on functions we fortify. Drop the object
678 size hints for such functions. */
679 # if __USE_FORTIFY_LEVEL == 3
680 # define __fortified_attr_access(a, o, s) __attribute__ ((__access__ (a, o)))
681 # else
682 # define __fortified_attr_access(a, o, s) __attr_access ((a, o, s))
683 # endif
684 # if __GNUC_PREREQ (11, 0)
685 # define __attr_access_none(argno) __attribute__ ((__access__ (__none__, argno)))
686 # else
687 # define __attr_access_none(argno)
688 # endif
689 #else
690 # define __fortified_attr_access(a, o, s)
691 # define __attr_access(x)
692 # define __attr_access_none(argno)
693 #endif
695 #if __GNUC_PREREQ (11, 0)
696 /* Designates dealloc as a function to call to deallocate objects
697 allocated by the declared function. */
698 # define __attr_dealloc(dealloc, argno) \
699 __attribute__ ((__malloc__ (dealloc, argno)))
700 # define __attr_dealloc_free __attr_dealloc (__builtin_free, 1)
701 #else
702 # define __attr_dealloc(dealloc, argno)
703 # define __attr_dealloc_free
704 #endif
706 /* Specify that a function such as setjmp or vfork may return
707 twice. */
708 #if __GNUC_PREREQ (4, 1)
709 # define __attribute_returns_twice__ __attribute__ ((__returns_twice__))
710 #else
711 # define __attribute_returns_twice__ /* Ignore. */
712 #endif
714 #endif /* sys/cdefs.h */