1 | /* Copyright (C) 1992-2024 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__ && !defined __cplusplus |
31 | # error "You need a ISO C or 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 | || 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 |
59 | |
60 | #if defined __GNUC__ || defined __clang__ |
61 | |
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 |
71 | |
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 |
100 | |
101 | # if __GNUC_PREREQ (4, 3) || __glibc_has_attribute (__cold__) |
102 | # define __COLD __attribute__ ((__cold__)) |
103 | # else |
104 | # define __COLD |
105 | # endif |
106 | |
107 | #else /* Not GCC or clang. */ |
108 | |
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 |
115 | |
116 | # define __THROW |
117 | # define __THROWNL |
118 | # define __NTH(fct) fct |
119 | # define __COLD |
120 | |
121 | #endif /* GCC || clang. */ |
122 | |
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 |
127 | |
128 | /* For these things, GCC behaves the ANSI way normally, |
129 | and the non-ANSI way under -traditional. */ |
130 | |
131 | #define __CONCAT(x,y) x ## y |
132 | #define __STRING(x) #x |
133 | |
134 | /* This is not a typedef so `const __ptr_t' does the right thing. */ |
135 | #define __ptr_t void * |
136 | |
137 | |
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 |
146 | |
147 | |
148 | /* The overloadable attribute was added on clang 2.6. */ |
149 | #if defined __clang_major__ \ |
150 | && (__clang_major__ + (__clang_minor__ >= 6) > 2) |
151 | # define __attribute_overloadable__ __attribute__((__overloadable__)) |
152 | #else |
153 | # define __attribute_overloadable__ |
154 | #endif |
155 | |
156 | /* Fortify support. */ |
157 | #define __bos(ptr) __builtin_object_size (ptr, __USE_FORTIFY_LEVEL > 1) |
158 | #define __bos0(ptr) __builtin_object_size (ptr, 0) |
159 | |
160 | /* Use __builtin_dynamic_object_size at _FORTIFY_SOURCE=3 when available. */ |
161 | #if __USE_FORTIFY_LEVEL == 3 && (__glibc_clang_prereq (9, 0) \ |
162 | || __GNUC_PREREQ (12, 0)) |
163 | # define __glibc_objsize0(__o) __builtin_dynamic_object_size (__o, 0) |
164 | # define __glibc_objsize(__o) __builtin_dynamic_object_size (__o, 1) |
165 | #else |
166 | # define __glibc_objsize0(__o) __bos0 (__o) |
167 | # define __glibc_objsize(__o) __bos (__o) |
168 | #endif |
169 | |
170 | #if __USE_FORTIFY_LEVEL > 0 |
171 | /* Compile time conditions to choose between the regular, _chk and _chk_warn |
172 | variants. These conditions should get evaluated to constant and optimized |
173 | away. */ |
174 | |
175 | #define __glibc_safe_len_cond(__l, __s, __osz) ((__l) <= (__osz) / (__s)) |
176 | #define __glibc_unsigned_or_positive(__l) \ |
177 | ((__typeof (__l)) 0 < (__typeof (__l)) -1 \ |
178 | || (__builtin_constant_p (__l) && (__l) > 0)) |
179 | |
180 | /* Length is known to be safe at compile time if the __L * __S <= __OBJSZ |
181 | condition can be folded to a constant and if it is true, or unknown (-1) */ |
182 | #define __glibc_safe_or_unknown_len(__l, __s, __osz) \ |
183 | ((__builtin_constant_p (__osz) && (__osz) == (__SIZE_TYPE__) -1) \ |
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 | /* Conversely, we know at compile time that the length is unsafe if the |
190 | __L * __S <= __OBJSZ condition can be folded to a constant and if it is |
191 | false. */ |
192 | #define __glibc_unsafe_len(__l, __s, __osz) \ |
193 | (__glibc_unsigned_or_positive (__l) \ |
194 | && __builtin_constant_p (__glibc_safe_len_cond ((__SIZE_TYPE__) (__l), \ |
195 | __s, __osz)) \ |
196 | && !__glibc_safe_len_cond ((__SIZE_TYPE__) (__l), __s, __osz)) |
197 | |
198 | /* To correctly instrument the fortify wrapper clang requires the |
199 | pass_object_size attribute, and the attribute has the restriction that the |
200 | argument needs to be 'const'. Furthermore, to make it usable with C |
201 | interfaces, clang provides the overload attribute, which provides a C++ |
202 | like function overload support. The overloaded fortify wrapper with the |
203 | pass_object_size attribute has precedence over the default symbol. |
204 | |
205 | Also, clang does not support __va_arg_pack, so variadic functions are |
206 | expanded to issue va_arg implementations. The error function must not have |
207 | bodies (address takes are expanded to nonfortified calls), and with |
208 | __fortify_function compiler might still create a body with the C++ |
209 | mangling name (due to the overload attribute). In this case, the function |
210 | is defined with __fortify_function_error_function macro instead. |
211 | |
212 | The argument size check is also done with a clang-only attribute, |
213 | __attribute__ ((__diagnose_if__ (...))), different than gcc which calls |
214 | symbol_chk_warn alias with uses __warnattr attribute. |
215 | |
216 | The pass_object_size was added on clang 4.0, __diagnose_if__ on 5.0, |
217 | and pass_dynamic_object_size on 9.0. */ |
218 | #if defined __clang_major__ && __clang_major__ >= 5 |
219 | # define __fortify_use_clang 1 |
220 | |
221 | # define __fortify_function_error_function static __attribute__((__unused__)) |
222 | |
223 | # define __fortify_clang_pass_object_size_n(n) \ |
224 | __attribute__ ((__pass_object_size__ (n))) |
225 | # define __fortify_clang_pass_object_size0 \ |
226 | __fortify_clang_pass_object_size_n (0) |
227 | # define __fortify_clang_pass_object_size \ |
228 | __fortify_clang_pass_object_size_n (__USE_FORTIFY_LEVEL > 1) |
229 | |
230 | # if __clang_major__ >= 9 |
231 | # define __fortify_clang_pass_dynamic_object_size_n(n) \ |
232 | __attribute__ ((__pass_dynamic_object_size__ (n))) |
233 | # define __fortify_clang_pass_dynamic_object_size0 \ |
234 | __fortify_clang_pass_dynamic_object_size_n (0) |
235 | # define __fortify_clang_pass_dynamic_object_size \ |
236 | __fortify_clang_pass_dynamic_object_size_n (1) |
237 | # else |
238 | # define __fortify_clang_pass_dynamic_object_size_n(n) |
239 | # define __fortify_clang_pass_dynamic_object_size0 |
240 | # define __fortify_clang_pass_dynamic_object_size |
241 | # endif |
242 | |
243 | # define __fortify_clang_bos_static_lt_impl(bos_val, n, s) \ |
244 | ((bos_val) != -1ULL && (n) > (bos_val) / (s)) |
245 | # define __fortify_clang_bos_static_lt2(__n, __e, __s) \ |
246 | __fortify_clang_bos_static_lt_impl (__bos (__e), __n, __s) |
247 | # define __fortify_clang_bos_static_lt(__n, __e) \ |
248 | __fortify_clang_bos_static_lt2 (__n, __e, 1) |
249 | # define __fortify_clang_bos0_static_lt2(__n, __e, __s) \ |
250 | __fortify_clang_bos_static_lt_impl (__bos0 (__e), __n, __s) |
251 | # define __fortify_clang_bos0_static_lt(__n, __e) \ |
252 | __fortify_clang_bos0_static_lt2 (__n, __e, 1) |
253 | |
254 | # define __fortify_clang_bosn_args(bos_fn, n, buf, div, complaint) \ |
255 | (__fortify_clang_bos_static_lt_impl (bos_fn (buf), n, div)), (complaint), \ |
256 | "warning" |
257 | |
258 | # define __fortify_clang_warning(__c, __msg) \ |
259 | __attribute__ ((__diagnose_if__ ((__c), (__msg), "warning"))) |
260 | # define __fortify_clang_error(__c, __msg) \ |
261 | __attribute__ ((__diagnose_if__ ((__c), (__msg), "error"))) |
262 | # define __fortify_clang_warning_only_if_bos0_lt(n, buf, complaint) \ |
263 | __attribute__ ((__diagnose_if__ \ |
264 | (__fortify_clang_bosn_args (__bos0, n, buf, 1, complaint)))) |
265 | # define __fortify_clang_warning_only_if_bos0_lt2(n, buf, div, complaint) \ |
266 | __attribute__ ((__diagnose_if__ \ |
267 | (__fortify_clang_bosn_args (__bos0, n, buf, div, complaint)))) |
268 | # define __fortify_clang_warning_only_if_bos_lt(n, buf, complaint) \ |
269 | __attribute__ ((__diagnose_if__ \ |
270 | (__fortify_clang_bosn_args (__bos, n, buf, 1, complaint)))) |
271 | # define __fortify_clang_warning_only_if_bos_lt2(n, buf, div, complaint) \ |
272 | __attribute__ ((__diagnose_if__ \ |
273 | (__fortify_clang_bosn_args (__bos, n, buf, div, complaint)))) |
274 | |
275 | # define __fortify_clang_prefer_this_overload \ |
276 | __attribute__ ((enable_if (1, ""))) |
277 | # define __fortify_clang_unavailable(__msg) \ |
278 | __attribute__ ((unavailable(__msg))) |
279 | |
280 | # if __USE_FORTIFY_LEVEL == 3 |
281 | # define __fortify_clang_overload_arg(__type, __attr, __name) \ |
282 | __type __attr const __fortify_clang_pass_dynamic_object_size __name |
283 | # define __fortify_clang_overload_arg0(__type, __attr, __name) \ |
284 | __type __attr const __fortify_clang_pass_dynamic_object_size0 __name |
285 | # else |
286 | # define __fortify_clang_overload_arg(__type, __attr, __name) \ |
287 | __type __attr const __fortify_clang_pass_object_size __name |
288 | # define __fortify_clang_overload_arg0(__type, __attr, __name) \ |
289 | __type __attr const __fortify_clang_pass_object_size0 __name |
290 | # endif |
291 | |
292 | # define __fortify_clang_mul_may_overflow(size, n) \ |
293 | ((size | n) >= (((size_t)1) << (8 * sizeof (size_t) / 2))) |
294 | |
295 | # define __fortify_clang_size_too_small(__bos, __dest, __len) \ |
296 | (__bos (__dest) != (size_t) -1 && __bos (__dest) < __len) |
297 | # define __fortify_clang_warn_if_src_too_large(__dest, __src) \ |
298 | __fortify_clang_warning (__fortify_clang_size_too_small (__glibc_objsize, \ |
299 | __dest, \ |
300 | __builtin_strlen (__src) + 1), \ |
301 | "destination buffer will always be overflown by source") |
302 | # define __fortify_clang_warn_if_dest_too_small(__dest, __len) \ |
303 | __fortify_clang_warning (__fortify_clang_size_too_small (__glibc_objsize, \ |
304 | __dest, \ |
305 | __len), \ |
306 | "function called with bigger length than the destination buffer") |
307 | # define __fortify_clang_warn_if_dest_too_small0(__dest, __len) \ |
308 | __fortify_clang_warning (__fortify_clang_size_too_small (__glibc_objsize0, \ |
309 | __dest, \ |
310 | __len), \ |
311 | "function called with bigger length than the destination buffer") |
312 | #else |
313 | # define __fortify_use_clang 0 |
314 | # define __fortify_clang_warning(__c, __msg) |
315 | # define __fortify_clang_warning_only_if_bos0_lt(__n, __buf, __complaint) |
316 | # define __fortify_clang_warning_only_if_bos0_lt2(__n, __buf, __div, complaint) |
317 | # define __fortify_clang_warning_only_if_bos_lt(__n, __buf, __complaint) |
318 | # define __fortify_clang_warning_only_if_bos_lt2(__n, __buf, div, __complaint) |
319 | # define __fortify_clang_overload_arg(__type, __attr, __name) \ |
320 | __type __attr __name |
321 | # define __fortify_clang_overload_arg0(__type, __attr, __name) \ |
322 | __fortify_clang_overload_arg (__type, __attr, __name) |
323 | # define __fortify_clang_warn_if_src_too_large(__dest, __src) |
324 | # define __fortify_clang_warn_if_dest_too_small(__dest, __len) |
325 | # define __fortify_clang_warn_if_dest_too_small0(__dest, __len) |
326 | #endif |
327 | |
328 | |
329 | /* Fortify function f. __f_alias, __f_chk and __f_chk_warn must be |
330 | declared. */ |
331 | |
332 | #if !__fortify_use_clang |
333 | # define __glibc_fortify(f, __l, __s, __osz, ...) \ |
334 | (__glibc_safe_or_unknown_len (__l, __s, __osz) \ |
335 | ? __ ## f ## _alias (__VA_ARGS__) \ |
336 | : (__glibc_unsafe_len (__l, __s, __osz) \ |
337 | ? __ ## f ## _chk_warn (__VA_ARGS__, __osz) \ |
338 | : __ ## f ## _chk (__VA_ARGS__, __osz))) |
339 | #else |
340 | # define __glibc_fortify(f, __l, __s, __osz, ...) \ |
341 | (__osz == (__SIZE_TYPE__) -1) \ |
342 | ? __ ## f ## _alias (__VA_ARGS__) \ |
343 | : __ ## f ## _chk (__VA_ARGS__, __osz) |
344 | #endif |
345 | |
346 | /* Fortify function f, where object size argument passed to f is the number of |
347 | elements and not total size. */ |
348 | |
349 | #if !__fortify_use_clang |
350 | # define __glibc_fortify_n(f, __l, __s, __osz, ...) \ |
351 | (__glibc_safe_or_unknown_len (__l, __s, __osz) \ |
352 | ? __ ## f ## _alias (__VA_ARGS__) \ |
353 | : (__glibc_unsafe_len (__l, __s, __osz) \ |
354 | ? __ ## f ## _chk_warn (__VA_ARGS__, (__osz) / (__s)) \ |
355 | : __ ## f ## _chk (__VA_ARGS__, (__osz) / (__s)))) |
356 | # else |
357 | # define __glibc_fortify_n(f, __l, __s, __osz, ...) \ |
358 | (__osz == (__SIZE_TYPE__) -1) \ |
359 | ? __ ## f ## _alias (__VA_ARGS__) \ |
360 | : __ ## f ## _chk (__VA_ARGS__, (__osz) / (__s)) |
361 | #endif |
362 | |
363 | #endif /* __USE_FORTIFY_LEVEL > 0 */ |
364 | |
365 | #if __GNUC_PREREQ (4,3) |
366 | # define __warnattr(msg) __attribute__((__warning__ (msg))) |
367 | # define __errordecl(name, msg) \ |
368 | extern void name (void) __attribute__((__error__ (msg))) |
369 | #else |
370 | # define __warnattr(msg) |
371 | # define __errordecl(name, msg) extern void name (void) |
372 | #endif |
373 | |
374 | /* Support for flexible arrays. |
375 | Headers that should use flexible arrays only if they're "real" |
376 | (e.g. only if they won't affect sizeof()) should test |
377 | #if __glibc_c99_flexarr_available. */ |
378 | #if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L && !defined __HP_cc |
379 | # define __flexarr [] |
380 | # define __glibc_c99_flexarr_available 1 |
381 | #elif __GNUC_PREREQ (2,97) || defined __clang__ |
382 | /* GCC 2.97 and clang support C99 flexible array members as an extension, |
383 | even when in C89 mode or compiling C++ (any version). */ |
384 | # define __flexarr [] |
385 | # define __glibc_c99_flexarr_available 1 |
386 | #elif defined __GNUC__ |
387 | /* Pre-2.97 GCC did not support C99 flexible arrays but did have |
388 | an equivalent extension with slightly different notation. */ |
389 | # define __flexarr [0] |
390 | # define __glibc_c99_flexarr_available 1 |
391 | #else |
392 | /* Some other non-C99 compiler. Approximate with [1]. */ |
393 | # define __flexarr [1] |
394 | # define __glibc_c99_flexarr_available 0 |
395 | #endif |
396 | |
397 | |
398 | /* __asm__ ("xyz") is used throughout the headers to rename functions |
399 | at the assembly language level. This is wrapped by the __REDIRECT |
400 | macro, in order to support compilers that can do this some other |
401 | way. When compilers don't support asm-names at all, we have to do |
402 | preprocessor tricks instead (which don't have exactly the right |
403 | semantics, but it's the best we can do). |
404 | |
405 | Example: |
406 | int __REDIRECT(setpgrp, (__pid_t pid, __pid_t pgrp), setpgid); */ |
407 | |
408 | #if (defined __GNUC__ && __GNUC__ >= 2) || (__clang_major__ >= 4) |
409 | |
410 | # define __REDIRECT(name, proto, alias) name proto __asm__ (__ASMNAME (#alias)) |
411 | # ifdef __cplusplus |
412 | # define __REDIRECT_NTH(name, proto, alias) \ |
413 | name proto __THROW __asm__ (__ASMNAME (#alias)) |
414 | # define __REDIRECT_NTHNL(name, proto, alias) \ |
415 | name proto __THROWNL __asm__ (__ASMNAME (#alias)) |
416 | # else |
417 | # define __REDIRECT_NTH(name, proto, alias) \ |
418 | name proto __asm__ (__ASMNAME (#alias)) __THROW |
419 | # define __REDIRECT_NTHNL(name, proto, alias) \ |
420 | name proto __asm__ (__ASMNAME (#alias)) __THROWNL |
421 | # endif |
422 | # define __ASMNAME(cname) __ASMNAME2 (__USER_LABEL_PREFIX__, cname) |
423 | # define __ASMNAME2(prefix, cname) __STRING (prefix) cname |
424 | |
425 | #ifndef __REDIRECT_FORTIFY |
426 | #define __REDIRECT_FORTIFY __REDIRECT |
427 | #endif |
428 | |
429 | #ifndef __REDIRECT_FORTIFY_NTH |
430 | #define __REDIRECT_FORTIFY_NTH __REDIRECT_NTH |
431 | #endif |
432 | |
433 | /* |
434 | #elif __SOME_OTHER_COMPILER__ |
435 | |
436 | # define __REDIRECT(name, proto, alias) name proto; \ |
437 | _Pragma("let " #name " = " #alias) |
438 | */ |
439 | #endif |
440 | |
441 | /* GCC and clang have various useful declarations that can be made with |
442 | the '__attribute__' syntax. All of the ways we use this do fine if |
443 | they are omitted for compilers that don't understand it. */ |
444 | #if !(defined __GNUC__ || defined __clang__) |
445 | # define __attribute__(xyz) /* Ignore */ |
446 | #endif |
447 | |
448 | /* At some point during the gcc 2.96 development the `malloc' attribute |
449 | for functions was introduced. We don't want to use it unconditionally |
450 | (although this would be possible) since it generates warnings. */ |
451 | #if __GNUC_PREREQ (2,96) || __glibc_has_attribute (__malloc__) |
452 | # define __attribute_malloc__ __attribute__ ((__malloc__)) |
453 | #else |
454 | # define __attribute_malloc__ /* Ignore */ |
455 | #endif |
456 | |
457 | /* Tell the compiler which arguments to an allocation function |
458 | indicate the size of the allocation. */ |
459 | #if __GNUC_PREREQ (4, 3) |
460 | # define __attribute_alloc_size__(params) \ |
461 | __attribute__ ((__alloc_size__ params)) |
462 | #else |
463 | # define __attribute_alloc_size__(params) /* Ignore. */ |
464 | #endif |
465 | |
466 | /* Tell the compiler which argument to an allocation function |
467 | indicates the alignment of the allocation. */ |
468 | #if __GNUC_PREREQ (4, 9) || __glibc_has_attribute (__alloc_align__) |
469 | # define __attribute_alloc_align__(param) \ |
470 | __attribute__ ((__alloc_align__ param)) |
471 | #else |
472 | # define __attribute_alloc_align__(param) /* Ignore. */ |
473 | #endif |
474 | |
475 | /* At some point during the gcc 2.96 development the `pure' attribute |
476 | for functions was introduced. We don't want to use it unconditionally |
477 | (although this would be possible) since it generates warnings. */ |
478 | #if __GNUC_PREREQ (2,96) || __glibc_has_attribute (__pure__) |
479 | # define __attribute_pure__ __attribute__ ((__pure__)) |
480 | #else |
481 | # define __attribute_pure__ /* Ignore */ |
482 | #endif |
483 | |
484 | /* This declaration tells the compiler that the value is constant. */ |
485 | #if __GNUC_PREREQ (2,5) || __glibc_has_attribute (__const__) |
486 | # define __attribute_const__ __attribute__ ((__const__)) |
487 | #else |
488 | # define __attribute_const__ /* Ignore */ |
489 | #endif |
490 | |
491 | #if __GNUC_PREREQ (2,7) || __glibc_has_attribute (__unused__) |
492 | # define __attribute_maybe_unused__ __attribute__ ((__unused__)) |
493 | #else |
494 | # define __attribute_maybe_unused__ /* Ignore */ |
495 | #endif |
496 | |
497 | /* At some point during the gcc 3.1 development the `used' attribute |
498 | for functions was introduced. We don't want to use it unconditionally |
499 | (although this would be possible) since it generates warnings. */ |
500 | #if __GNUC_PREREQ (3,1) || __glibc_has_attribute (__used__) |
501 | # define __attribute_used__ __attribute__ ((__used__)) |
502 | # define __attribute_noinline__ __attribute__ ((__noinline__)) |
503 | #else |
504 | # define __attribute_used__ __attribute__ ((__unused__)) |
505 | # define __attribute_noinline__ /* Ignore */ |
506 | #endif |
507 | |
508 | /* Since version 3.2, gcc allows marking deprecated functions. */ |
509 | #if __GNUC_PREREQ (3,2) || __glibc_has_attribute (__deprecated__) |
510 | # define __attribute_deprecated__ __attribute__ ((__deprecated__)) |
511 | #else |
512 | # define __attribute_deprecated__ /* Ignore */ |
513 | #endif |
514 | |
515 | /* Since version 4.5, gcc also allows one to specify the message printed |
516 | when a deprecated function is used. clang claims to be gcc 4.2, but |
517 | may also support this feature. */ |
518 | #if __GNUC_PREREQ (4,5) \ |
519 | || __glibc_has_extension (__attribute_deprecated_with_message__) |
520 | # define __attribute_deprecated_msg__(msg) \ |
521 | __attribute__ ((__deprecated__ (msg))) |
522 | #else |
523 | # define __attribute_deprecated_msg__(msg) __attribute_deprecated__ |
524 | #endif |
525 | |
526 | /* At some point during the gcc 2.8 development the `format_arg' attribute |
527 | for functions was introduced. We don't want to use it unconditionally |
528 | (although this would be possible) since it generates warnings. |
529 | If several `format_arg' attributes are given for the same function, in |
530 | gcc-3.0 and older, all but the last one are ignored. In newer gccs, |
531 | all designated arguments are considered. */ |
532 | #if __GNUC_PREREQ (2,8) || __glibc_has_attribute (__format_arg__) |
533 | # define __attribute_format_arg__(x) __attribute__ ((__format_arg__ (x))) |
534 | #else |
535 | # define __attribute_format_arg__(x) /* Ignore */ |
536 | #endif |
537 | |
538 | /* At some point during the gcc 2.97 development the `strfmon' format |
539 | attribute for functions was introduced. We don't want to use it |
540 | unconditionally (although this would be possible) since it |
541 | generates warnings. */ |
542 | #if __GNUC_PREREQ (2,97) || __glibc_has_attribute (__format__) |
543 | # define __attribute_format_strfmon__(a,b) \ |
544 | __attribute__ ((__format__ (__strfmon__, a, b))) |
545 | #else |
546 | # define __attribute_format_strfmon__(a,b) /* Ignore */ |
547 | #endif |
548 | |
549 | /* The nonnull function attribute marks pointer parameters that |
550 | must not be NULL. This has the name __nonnull in glibc, |
551 | and __attribute_nonnull__ in files shared with Gnulib to avoid |
552 | collision with a different __nonnull in DragonFlyBSD 5.9. */ |
553 | #ifndef __attribute_nonnull__ |
554 | # if __GNUC_PREREQ (3,3) || __glibc_has_attribute (__nonnull__) |
555 | # define __attribute_nonnull__(params) __attribute__ ((__nonnull__ params)) |
556 | # else |
557 | # define __attribute_nonnull__(params) |
558 | # endif |
559 | #endif |
560 | #ifndef __nonnull |
561 | # define __nonnull(params) __attribute_nonnull__ (params) |
562 | #endif |
563 | |
564 | /* The returns_nonnull function attribute marks the return type of the function |
565 | as always being non-null. */ |
566 | #ifndef __returns_nonnull |
567 | # if __GNUC_PREREQ (4, 9) || __glibc_has_attribute (__returns_nonnull__) |
568 | # define __returns_nonnull __attribute__ ((__returns_nonnull__)) |
569 | # else |
570 | # define __returns_nonnull |
571 | # endif |
572 | #endif |
573 | |
574 | /* If fortification mode, we warn about unused results of certain |
575 | function calls which can lead to problems. */ |
576 | #if __GNUC_PREREQ (3,4) || __glibc_has_attribute (__warn_unused_result__) |
577 | # define __attribute_warn_unused_result__ \ |
578 | __attribute__ ((__warn_unused_result__)) |
579 | # if defined __USE_FORTIFY_LEVEL && __USE_FORTIFY_LEVEL > 0 |
580 | # define __wur __attribute_warn_unused_result__ |
581 | # endif |
582 | #else |
583 | # define __attribute_warn_unused_result__ /* empty */ |
584 | #endif |
585 | #ifndef __wur |
586 | # define __wur /* Ignore */ |
587 | #endif |
588 | |
589 | /* Forces a function to be always inlined. */ |
590 | #if __GNUC_PREREQ (3,2) || __glibc_has_attribute (__always_inline__) |
591 | /* The Linux kernel defines __always_inline in stddef.h (283d7573), and |
592 | it conflicts with this definition. Therefore undefine it first to |
593 | allow either header to be included first. */ |
594 | # undef __always_inline |
595 | # define __always_inline __inline __attribute__ ((__always_inline__)) |
596 | #else |
597 | # undef __always_inline |
598 | # define __always_inline __inline |
599 | #endif |
600 | |
601 | /* Associate error messages with the source location of the call site rather |
602 | than with the source location inside the function. */ |
603 | #if __GNUC_PREREQ (4,3) || __glibc_has_attribute (__artificial__) |
604 | # define __attribute_artificial__ __attribute__ ((__artificial__)) |
605 | #else |
606 | # define __attribute_artificial__ /* Ignore */ |
607 | #endif |
608 | |
609 | /* GCC 4.3 and above with -std=c99 or -std=gnu99 implements ISO C99 |
610 | inline semantics, unless -fgnu89-inline is used. Using __GNUC_STDC_INLINE__ |
611 | or __GNUC_GNU_INLINE is not a good enough check for gcc because gcc versions |
612 | older than 4.3 may define these macros and still not guarantee GNU inlining |
613 | semantics. |
614 | |
615 | clang++ identifies itself as gcc-4.2, but has support for GNU inlining |
616 | semantics, that can be checked for by using the __GNUC_STDC_INLINE_ and |
617 | __GNUC_GNU_INLINE__ macro definitions. */ |
618 | #if (!defined __cplusplus || __GNUC_PREREQ (4,3) \ |
619 | || (defined __clang__ && (defined __GNUC_STDC_INLINE__ \ |
620 | || defined __GNUC_GNU_INLINE__))) |
621 | # if defined __GNUC_STDC_INLINE__ || defined __cplusplus |
622 | # define __extern_inline extern __inline __attribute__ ((__gnu_inline__)) |
623 | # define __extern_always_inline \ |
624 | extern __always_inline __attribute__ ((__gnu_inline__)) |
625 | # else |
626 | # define __extern_inline extern __inline |
627 | # define __extern_always_inline extern __always_inline |
628 | # endif |
629 | #endif |
630 | |
631 | #ifdef __extern_always_inline |
632 | # define __fortify_function __extern_always_inline __attribute_artificial__ |
633 | #endif |
634 | |
635 | /* GCC 4.3 and above allow passing all anonymous arguments of an |
636 | __extern_always_inline function to some other vararg function. */ |
637 | #if __GNUC_PREREQ (4,3) |
638 | # define __va_arg_pack() __builtin_va_arg_pack () |
639 | # define __va_arg_pack_len() __builtin_va_arg_pack_len () |
640 | #endif |
641 | |
642 | /* It is possible to compile containing GCC extensions even if GCC is |
643 | run in pedantic mode if the uses are carefully marked using the |
644 | `__extension__' keyword. But this is not generally available before |
645 | version 2.8. */ |
646 | #if !(__GNUC_PREREQ (2,8) || defined __clang__) |
647 | # define __extension__ /* Ignore */ |
648 | #endif |
649 | |
650 | /* __restrict is known in EGCS 1.2 and above, and in clang. |
651 | It works also in C++ mode (outside of arrays), but only when spelled |
652 | as '__restrict', not 'restrict'. */ |
653 | #if !(__GNUC_PREREQ (2,92) || __clang_major__ >= 3) |
654 | # if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L |
655 | # define __restrict restrict |
656 | # else |
657 | # define __restrict /* Ignore */ |
658 | # endif |
659 | #endif |
660 | |
661 | /* ISO C99 also allows to declare arrays as non-overlapping. The syntax is |
662 | array_name[restrict] |
663 | GCC 3.1 and clang support this. |
664 | This syntax is not usable in C++ mode. */ |
665 | #if (__GNUC_PREREQ (3,1) || __clang_major__ >= 3) && !defined __cplusplus |
666 | # define __restrict_arr __restrict |
667 | #else |
668 | # ifdef __GNUC__ |
669 | # define __restrict_arr /* Not supported in old GCC. */ |
670 | # else |
671 | # if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L |
672 | # define __restrict_arr restrict |
673 | # else |
674 | /* Some other non-C99 compiler. */ |
675 | # define __restrict_arr /* Not supported. */ |
676 | # endif |
677 | # endif |
678 | #endif |
679 | |
680 | #if (__GNUC__ >= 3) || __glibc_has_builtin (__builtin_expect) |
681 | # define __glibc_unlikely(cond) __builtin_expect ((cond), 0) |
682 | # define __glibc_likely(cond) __builtin_expect ((cond), 1) |
683 | #else |
684 | # define __glibc_unlikely(cond) (cond) |
685 | # define __glibc_likely(cond) (cond) |
686 | #endif |
687 | |
688 | #if (!defined _Noreturn \ |
689 | && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \ |
690 | && !(__GNUC_PREREQ (4,7) \ |
691 | || (3 < __clang_major__ + (5 <= __clang_minor__)))) |
692 | # if __GNUC_PREREQ (2,8) |
693 | # define _Noreturn __attribute__ ((__noreturn__)) |
694 | # else |
695 | # define _Noreturn |
696 | # endif |
697 | #endif |
698 | |
699 | #if __GNUC_PREREQ (8, 0) |
700 | /* Describes a char array whose address can safely be passed as the first |
701 | argument to strncpy and strncat, as the char array is not necessarily |
702 | a NUL-terminated string. */ |
703 | # define __attribute_nonstring__ __attribute__ ((__nonstring__)) |
704 | #else |
705 | # define __attribute_nonstring__ |
706 | #endif |
707 | |
708 | /* Undefine (also defined in libc-symbols.h). */ |
709 | #undef __attribute_copy__ |
710 | #if __GNUC_PREREQ (9, 0) |
711 | /* Copies attributes from the declaration or type referenced by |
712 | the argument. */ |
713 | # define __attribute_copy__(arg) __attribute__ ((__copy__ (arg))) |
714 | #else |
715 | # define __attribute_copy__(arg) |
716 | #endif |
717 | |
718 | #if (!defined _Static_assert && !defined __cplusplus \ |
719 | && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \ |
720 | && (!(__GNUC_PREREQ (4, 6) || __clang_major__ >= 4) \ |
721 | || defined __STRICT_ANSI__)) |
722 | # define _Static_assert(expr, diagnostic) \ |
723 | extern int (*__Static_assert_function (void)) \ |
724 | [!!sizeof (struct { int __error_if_negative: (expr) ? 2 : -1; })] |
725 | #endif |
726 | |
727 | /* Gnulib avoids including these, as they don't work on non-glibc or |
728 | older glibc platforms. */ |
729 | #ifndef __GNULIB_CDEFS |
730 | # include <bits/wordsize.h> |
731 | # include <bits/long-double.h> |
732 | #endif |
733 | |
734 | #if __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 1 |
735 | # ifdef __REDIRECT |
736 | |
737 | /* Alias name defined automatically. */ |
738 | # define __LDBL_REDIR(name, proto) ... unused__ldbl_redir |
739 | # define __LDBL_REDIR_DECL(name) \ |
740 | extern __typeof (name) name __asm (__ASMNAME ("__" #name "ieee128")); |
741 | # define __REDIRECT_LDBL(name, proto, alias) \ |
742 | name proto __asm (__ASMNAME ("__" #alias "ieee128")) |
743 | |
744 | /* Alias name defined automatically, with leading underscores. */ |
745 | # define __LDBL_REDIR2_DECL(name) \ |
746 | extern __typeof (__##name) __##name \ |
747 | __asm (__ASMNAME ("__" #name "ieee128")); |
748 | |
749 | /* Alias name defined manually. */ |
750 | # define __LDBL_REDIR1(name, proto, alias) ... unused__ldbl_redir1 |
751 | # define __LDBL_REDIR1_DECL(name, alias) \ |
752 | extern __typeof (name) name __asm (__ASMNAME (#alias)); |
753 | |
754 | # define __LDBL_REDIR1_NTH(name, proto, alias) \ |
755 | __REDIRECT_NTH (name, proto, alias) |
756 | # define __REDIRECT_NTH_LDBL(name, proto, alias) \ |
757 | __LDBL_REDIR1_NTH (name, proto, __##alias##ieee128) |
758 | |
759 | /* Unused. */ |
760 | # define __LDBL_REDIR_NTH(name, proto) ... unused__ldbl_redir_nth |
761 | |
762 | # else |
763 | _Static_assert (0, "IEEE 128-bits long double requires redirection on this platform" ); |
764 | # endif |
765 | #elif defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH |
766 | # define __LDBL_COMPAT 1 |
767 | # ifdef __REDIRECT |
768 | # define __LDBL_REDIR1(name, proto, alias) __REDIRECT (name, proto, alias) |
769 | # define __LDBL_REDIR(name, proto) \ |
770 | __LDBL_REDIR1 (name, proto, __nldbl_##name) |
771 | # define __LDBL_REDIR1_NTH(name, proto, alias) __REDIRECT_NTH (name, proto, alias) |
772 | # define __LDBL_REDIR_NTH(name, proto) \ |
773 | __LDBL_REDIR1_NTH (name, proto, __nldbl_##name) |
774 | # define __LDBL_REDIR2_DECL(name) \ |
775 | extern __typeof (__##name) __##name __asm (__ASMNAME ("__nldbl___" #name)); |
776 | # define __LDBL_REDIR1_DECL(name, alias) \ |
777 | extern __typeof (name) name __asm (__ASMNAME (#alias)); |
778 | # define __LDBL_REDIR_DECL(name) \ |
779 | extern __typeof (name) name __asm (__ASMNAME ("__nldbl_" #name)); |
780 | # define __REDIRECT_LDBL(name, proto, alias) \ |
781 | __LDBL_REDIR1 (name, proto, __nldbl_##alias) |
782 | # define __REDIRECT_NTH_LDBL(name, proto, alias) \ |
783 | __LDBL_REDIR1_NTH (name, proto, __nldbl_##alias) |
784 | # endif |
785 | #endif |
786 | #if (!defined __LDBL_COMPAT && __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 0) \ |
787 | || !defined __REDIRECT |
788 | # define __LDBL_REDIR1(name, proto, alias) name proto |
789 | # define __LDBL_REDIR(name, proto) name proto |
790 | # define __LDBL_REDIR1_NTH(name, proto, alias) name proto __THROW |
791 | # define __LDBL_REDIR_NTH(name, proto) name proto __THROW |
792 | # define __LDBL_REDIR2_DECL(name) |
793 | # define __LDBL_REDIR_DECL(name) |
794 | # ifdef __REDIRECT |
795 | # define __REDIRECT_LDBL(name, proto, alias) __REDIRECT (name, proto, alias) |
796 | # define __REDIRECT_NTH_LDBL(name, proto, alias) \ |
797 | __REDIRECT_NTH (name, proto, alias) |
798 | # endif |
799 | #endif |
800 | |
801 | /* __glibc_macro_warning (MESSAGE) issues warning MESSAGE. This is |
802 | intended for use in preprocessor macros. |
803 | |
804 | Note: MESSAGE must be a _single_ string; concatenation of string |
805 | literals is not supported. */ |
806 | #if __GNUC_PREREQ (4,8) || __glibc_clang_prereq (3,5) |
807 | # define __glibc_macro_warning1(message) _Pragma (#message) |
808 | # define __glibc_macro_warning(message) \ |
809 | __glibc_macro_warning1 (GCC warning message) |
810 | #else |
811 | # define __glibc_macro_warning(msg) |
812 | #endif |
813 | |
814 | /* Generic selection (ISO C11) is a C-only feature, available in GCC |
815 | since version 4.9. Previous versions do not provide generic |
816 | selection, even though they might set __STDC_VERSION__ to 201112L, |
817 | when in -std=c11 mode. Thus, we must check for !defined __GNUC__ |
818 | when testing __STDC_VERSION__ for generic selection support. |
819 | On the other hand, Clang also defines __GNUC__, so a clang-specific |
820 | check is required to enable the use of generic selection. */ |
821 | #if !defined __cplusplus \ |
822 | && (__GNUC_PREREQ (4, 9) \ |
823 | || __glibc_has_extension (c_generic_selections) \ |
824 | || (!defined __GNUC__ && defined __STDC_VERSION__ \ |
825 | && __STDC_VERSION__ >= 201112L)) |
826 | # define __HAVE_GENERIC_SELECTION 1 |
827 | #else |
828 | # define __HAVE_GENERIC_SELECTION 0 |
829 | #endif |
830 | |
831 | #if __GNUC_PREREQ (10, 0) |
832 | /* Designates a 1-based positional argument ref-index of pointer type |
833 | that can be used to access size-index elements of the pointed-to |
834 | array according to access mode, or at least one element when |
835 | size-index is not provided: |
836 | access (access-mode, <ref-index> [, <size-index>]) */ |
837 | # define __attr_access(x) __attribute__ ((__access__ x)) |
838 | /* For _FORTIFY_SOURCE == 3 we use __builtin_dynamic_object_size, which may |
839 | use the access attribute to get object sizes from function definition |
840 | arguments, so we can't use them on functions we fortify. Drop the access |
841 | attribute for such functions. */ |
842 | # if __USE_FORTIFY_LEVEL == 3 |
843 | # define __fortified_attr_access(a, o, s) |
844 | # else |
845 | # define __fortified_attr_access(a, o, s) __attr_access ((a, o, s)) |
846 | # endif |
847 | # if __GNUC_PREREQ (11, 0) |
848 | # define __attr_access_none(argno) __attribute__ ((__access__ (__none__, argno))) |
849 | # else |
850 | # define __attr_access_none(argno) |
851 | # endif |
852 | #else |
853 | # define __fortified_attr_access(a, o, s) |
854 | # define __attr_access(x) |
855 | # define __attr_access_none(argno) |
856 | #endif |
857 | |
858 | #if __GNUC_PREREQ (11, 0) |
859 | /* Designates dealloc as a function to call to deallocate objects |
860 | allocated by the declared function. */ |
861 | # define __attr_dealloc(dealloc, argno) \ |
862 | __attribute__ ((__malloc__ (dealloc, argno))) |
863 | # define __attr_dealloc_free __attr_dealloc (__builtin_free, 1) |
864 | #else |
865 | # define __attr_dealloc(dealloc, argno) |
866 | # define __attr_dealloc_free |
867 | #endif |
868 | |
869 | /* Specify that a function such as setjmp or vfork may return |
870 | twice. */ |
871 | #if __GNUC_PREREQ (4, 1) |
872 | # define __attribute_returns_twice__ __attribute__ ((__returns_twice__)) |
873 | #else |
874 | # define __attribute_returns_twice__ /* Ignore. */ |
875 | #endif |
876 | |
877 | /* Mark struct types as aliasable. Restricted to compilers that |
878 | support forward declarations of structs in the presence of the |
879 | attribute. */ |
880 | #if __GNUC_PREREQ (7, 1) || defined __clang__ |
881 | # define __attribute_struct_may_alias__ __attribute__ ((__may_alias__)) |
882 | #else |
883 | # define __attribute_struct_may_alias__ |
884 | #endif |
885 | |
886 | #endif /* sys/cdefs.h */ |
887 | |