1 | /* Copyright (C) 1992-2018 Free Software Foundation, Inc. |
2 | This file is part of the GNU C Library. |
3 | |
4 | The GNU C Library is free software; you can redistribute it and/or |
5 | modify it under the terms of the GNU Lesser General Public |
6 | License as published by the Free Software Foundation; either |
7 | version 2.1 of the License, or (at your option) any later version. |
8 | |
9 | The GNU C Library is distributed in the hope that it will be useful, |
10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
12 | Lesser General Public License for more details. |
13 | |
14 | You should have received a copy of the GNU Lesser General Public |
15 | License along with the GNU C Library; if not, see |
16 | <http://www.gnu.org/licenses/>. */ |
17 | |
18 | #ifndef _SYS_CDEFS_H |
19 | #define _SYS_CDEFS_H 1 |
20 | |
21 | /* We are almost always included from features.h. */ |
22 | #ifndef _FEATURES_H |
23 | # include <features.h> |
24 | #endif |
25 | |
26 | /* The GNU libc does not support any K&R compilers or the traditional mode |
27 | of ISO C compilers anymore. Check for some of the combinations not |
28 | anymore supported. */ |
29 | #if defined __GNUC__ && !defined __STDC__ |
30 | # error "You need a ISO C conforming compiler to use the glibc headers" |
31 | #endif |
32 | |
33 | /* Some user header file might have defined this before. */ |
34 | #undef __P |
35 | #undef __PMT |
36 | |
37 | #ifdef __GNUC__ |
38 | |
39 | /* All functions, except those with callbacks or those that |
40 | synchronize memory, are leaf functions. */ |
41 | # if __GNUC_PREREQ (4, 6) && !defined _LIBC |
42 | # define __LEAF , __leaf__ |
43 | # define __LEAF_ATTR __attribute__ ((__leaf__)) |
44 | # else |
45 | # define __LEAF |
46 | # define __LEAF_ATTR |
47 | # endif |
48 | |
49 | /* GCC can always grok prototypes. For C++ programs we add throw() |
50 | to help it optimize the function calls. But this works only with |
51 | gcc 2.8.x and egcs. For gcc 3.2 and up we even mark C functions |
52 | as non-throwing using a function attribute since programs can use |
53 | the -fexceptions options for C code as well. */ |
54 | # if !defined __cplusplus && __GNUC_PREREQ (3, 3) |
55 | # define __THROW __attribute__ ((__nothrow__ __LEAF)) |
56 | # define __THROWNL __attribute__ ((__nothrow__)) |
57 | # define __NTH(fct) __attribute__ ((__nothrow__ __LEAF)) fct |
58 | # define __NTHNL(fct) __attribute__ ((__nothrow__)) fct |
59 | # else |
60 | # if defined __cplusplus && __GNUC_PREREQ (2,8) |
61 | # define __THROW throw () |
62 | # define __THROWNL throw () |
63 | # define __NTH(fct) __LEAF_ATTR fct throw () |
64 | # define __NTHNL(fct) fct throw () |
65 | # else |
66 | # define __THROW |
67 | # define __THROWNL |
68 | # define __NTH(fct) fct |
69 | # define __NTHNL(fct) fct |
70 | # endif |
71 | # endif |
72 | |
73 | #else /* Not GCC. */ |
74 | |
75 | # define __inline /* No inline functions. */ |
76 | |
77 | # define __THROW |
78 | # define __THROWNL |
79 | # define __NTH(fct) fct |
80 | |
81 | #endif /* GCC. */ |
82 | |
83 | /* Compilers that are not clang may object to |
84 | #if defined __clang__ && __has_extension(...) |
85 | even though they do not need to evaluate the right-hand side of the &&. */ |
86 | #if defined __clang__ && defined __has_extension |
87 | # define __glibc_clang_has_extension(ext) __has_extension (ext) |
88 | #else |
89 | # define __glibc_clang_has_extension(ext) 0 |
90 | #endif |
91 | |
92 | /* These two macros are not used in glibc anymore. They are kept here |
93 | only because some other projects expect the macros to be defined. */ |
94 | #define __P(args) args |
95 | #define __PMT(args) args |
96 | |
97 | /* For these things, GCC behaves the ANSI way normally, |
98 | and the non-ANSI way under -traditional. */ |
99 | |
100 | #define __CONCAT(x,y) x ## y |
101 | #define __STRING(x) #x |
102 | |
103 | /* This is not a typedef so `const __ptr_t' does the right thing. */ |
104 | #define __ptr_t void * |
105 | |
106 | |
107 | /* C++ needs to know that types and declarations are C, not C++. */ |
108 | #ifdef __cplusplus |
109 | # define __BEGIN_DECLS extern "C" { |
110 | # define __END_DECLS } |
111 | #else |
112 | # define __BEGIN_DECLS |
113 | # define __END_DECLS |
114 | #endif |
115 | |
116 | |
117 | /* Fortify support. */ |
118 | #define __bos(ptr) __builtin_object_size (ptr, __USE_FORTIFY_LEVEL > 1) |
119 | #define __bos0(ptr) __builtin_object_size (ptr, 0) |
120 | |
121 | #if __GNUC_PREREQ (4,3) |
122 | # define __warndecl(name, msg) \ |
123 | extern void name (void) __attribute__((__warning__ (msg))) |
124 | # define __warnattr(msg) __attribute__((__warning__ (msg))) |
125 | # define __errordecl(name, msg) \ |
126 | extern void name (void) __attribute__((__error__ (msg))) |
127 | #else |
128 | # define __warndecl(name, msg) extern void name (void) |
129 | # define __warnattr(msg) |
130 | # define __errordecl(name, msg) extern void name (void) |
131 | #endif |
132 | |
133 | /* Support for flexible arrays. |
134 | Headers that should use flexible arrays only if they're "real" |
135 | (e.g. only if they won't affect sizeof()) should test |
136 | #if __glibc_c99_flexarr_available. */ |
137 | #if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L |
138 | # define __flexarr [] |
139 | # define __glibc_c99_flexarr_available 1 |
140 | #elif __GNUC_PREREQ (2,97) |
141 | /* GCC 2.97 supports C99 flexible array members as an extension, |
142 | even when in C89 mode or compiling C++ (any version). */ |
143 | # define __flexarr [] |
144 | # define __glibc_c99_flexarr_available 1 |
145 | #elif defined __GNUC__ |
146 | /* Pre-2.97 GCC did not support C99 flexible arrays but did have |
147 | an equivalent extension with slightly different notation. */ |
148 | # define __flexarr [0] |
149 | # define __glibc_c99_flexarr_available 1 |
150 | #else |
151 | /* Some other non-C99 compiler. Approximate with [1]. */ |
152 | # define __flexarr [1] |
153 | # define __glibc_c99_flexarr_available 0 |
154 | #endif |
155 | |
156 | |
157 | /* __asm__ ("xyz") is used throughout the headers to rename functions |
158 | at the assembly language level. This is wrapped by the __REDIRECT |
159 | macro, in order to support compilers that can do this some other |
160 | way. When compilers don't support asm-names at all, we have to do |
161 | preprocessor tricks instead (which don't have exactly the right |
162 | semantics, but it's the best we can do). |
163 | |
164 | Example: |
165 | int __REDIRECT(setpgrp, (__pid_t pid, __pid_t pgrp), setpgid); */ |
166 | |
167 | #if defined __GNUC__ && __GNUC__ >= 2 |
168 | |
169 | # define __REDIRECT(name, proto, alias) name proto __asm__ (__ASMNAME (#alias)) |
170 | # ifdef __cplusplus |
171 | # define __REDIRECT_NTH(name, proto, alias) \ |
172 | name proto __THROW __asm__ (__ASMNAME (#alias)) |
173 | # define __REDIRECT_NTHNL(name, proto, alias) \ |
174 | name proto __THROWNL __asm__ (__ASMNAME (#alias)) |
175 | # else |
176 | # define __REDIRECT_NTH(name, proto, alias) \ |
177 | name proto __asm__ (__ASMNAME (#alias)) __THROW |
178 | # define __REDIRECT_NTHNL(name, proto, alias) \ |
179 | name proto __asm__ (__ASMNAME (#alias)) __THROWNL |
180 | # endif |
181 | # define __ASMNAME(cname) __ASMNAME2 (__USER_LABEL_PREFIX__, cname) |
182 | # define __ASMNAME2(prefix, cname) __STRING (prefix) cname |
183 | |
184 | /* |
185 | #elif __SOME_OTHER_COMPILER__ |
186 | |
187 | # define __REDIRECT(name, proto, alias) name proto; \ |
188 | _Pragma("let " #name " = " #alias) |
189 | */ |
190 | #endif |
191 | |
192 | /* GCC has various useful declarations that can be made with the |
193 | `__attribute__' syntax. All of the ways we use this do fine if |
194 | they are omitted for compilers that don't understand it. */ |
195 | #if !defined __GNUC__ || __GNUC__ < 2 |
196 | # define __attribute__(xyz) /* Ignore */ |
197 | #endif |
198 | |
199 | /* At some point during the gcc 2.96 development the `malloc' attribute |
200 | for functions was introduced. We don't want to use it unconditionally |
201 | (although this would be possible) since it generates warnings. */ |
202 | #if __GNUC_PREREQ (2,96) |
203 | # define __attribute_malloc__ __attribute__ ((__malloc__)) |
204 | #else |
205 | # define __attribute_malloc__ /* Ignore */ |
206 | #endif |
207 | |
208 | /* Tell the compiler which arguments to an allocation function |
209 | indicate the size of the allocation. */ |
210 | #if __GNUC_PREREQ (4, 3) |
211 | # define __attribute_alloc_size__(params) \ |
212 | __attribute__ ((__alloc_size__ params)) |
213 | #else |
214 | # define __attribute_alloc_size__(params) /* Ignore. */ |
215 | #endif |
216 | |
217 | /* At some point during the gcc 2.96 development the `pure' attribute |
218 | for functions was introduced. We don't want to use it unconditionally |
219 | (although this would be possible) since it generates warnings. */ |
220 | #if __GNUC_PREREQ (2,96) |
221 | # define __attribute_pure__ __attribute__ ((__pure__)) |
222 | #else |
223 | # define __attribute_pure__ /* Ignore */ |
224 | #endif |
225 | |
226 | /* This declaration tells the compiler that the value is constant. */ |
227 | #if __GNUC_PREREQ (2,5) |
228 | # define __attribute_const__ __attribute__ ((__const__)) |
229 | #else |
230 | # define __attribute_const__ /* Ignore */ |
231 | #endif |
232 | |
233 | /* At some point during the gcc 3.1 development the `used' attribute |
234 | for functions was introduced. We don't want to use it unconditionally |
235 | (although this would be possible) since it generates warnings. */ |
236 | #if __GNUC_PREREQ (3,1) |
237 | # define __attribute_used__ __attribute__ ((__used__)) |
238 | # define __attribute_noinline__ __attribute__ ((__noinline__)) |
239 | #else |
240 | # define __attribute_used__ __attribute__ ((__unused__)) |
241 | # define __attribute_noinline__ /* Ignore */ |
242 | #endif |
243 | |
244 | /* Since version 3.2, gcc allows marking deprecated functions. */ |
245 | #if __GNUC_PREREQ (3,2) |
246 | # define __attribute_deprecated__ __attribute__ ((__deprecated__)) |
247 | #else |
248 | # define __attribute_deprecated__ /* Ignore */ |
249 | #endif |
250 | |
251 | /* Since version 4.5, gcc also allows one to specify the message printed |
252 | when a deprecated function is used. clang claims to be gcc 4.2, but |
253 | may also support this feature. */ |
254 | #if __GNUC_PREREQ (4,5) || \ |
255 | __glibc_clang_has_extension (__attribute_deprecated_with_message__) |
256 | # define __attribute_deprecated_msg__(msg) \ |
257 | __attribute__ ((__deprecated__ (msg))) |
258 | #else |
259 | # define __attribute_deprecated_msg__(msg) __attribute_deprecated__ |
260 | #endif |
261 | |
262 | /* At some point during the gcc 2.8 development the `format_arg' attribute |
263 | for functions was introduced. We don't want to use it unconditionally |
264 | (although this would be possible) since it generates warnings. |
265 | If several `format_arg' attributes are given for the same function, in |
266 | gcc-3.0 and older, all but the last one are ignored. In newer gccs, |
267 | all designated arguments are considered. */ |
268 | #if __GNUC_PREREQ (2,8) |
269 | # define __attribute_format_arg__(x) __attribute__ ((__format_arg__ (x))) |
270 | #else |
271 | # define __attribute_format_arg__(x) /* Ignore */ |
272 | #endif |
273 | |
274 | /* At some point during the gcc 2.97 development the `strfmon' format |
275 | attribute for functions was introduced. We don't want to use it |
276 | unconditionally (although this would be possible) since it |
277 | generates warnings. */ |
278 | #if __GNUC_PREREQ (2,97) |
279 | # define __attribute_format_strfmon__(a,b) \ |
280 | __attribute__ ((__format__ (__strfmon__, a, b))) |
281 | #else |
282 | # define __attribute_format_strfmon__(a,b) /* Ignore */ |
283 | #endif |
284 | |
285 | /* The nonull function attribute allows to mark pointer parameters which |
286 | must not be NULL. */ |
287 | #if __GNUC_PREREQ (3,3) |
288 | # define __nonnull(params) __attribute__ ((__nonnull__ params)) |
289 | #else |
290 | # define __nonnull(params) |
291 | #endif |
292 | |
293 | /* If fortification mode, we warn about unused results of certain |
294 | function calls which can lead to problems. */ |
295 | #if __GNUC_PREREQ (3,4) |
296 | # define __attribute_warn_unused_result__ \ |
297 | __attribute__ ((__warn_unused_result__)) |
298 | # if __USE_FORTIFY_LEVEL > 0 |
299 | # define __wur __attribute_warn_unused_result__ |
300 | # endif |
301 | #else |
302 | # define __attribute_warn_unused_result__ /* empty */ |
303 | #endif |
304 | #ifndef __wur |
305 | # define __wur /* Ignore */ |
306 | #endif |
307 | |
308 | /* Forces a function to be always inlined. */ |
309 | #if __GNUC_PREREQ (3,2) |
310 | /* The Linux kernel defines __always_inline in stddef.h (283d7573), and |
311 | it conflicts with this definition. Therefore undefine it first to |
312 | allow either header to be included first. */ |
313 | # undef __always_inline |
314 | # define __always_inline __inline __attribute__ ((__always_inline__)) |
315 | #else |
316 | # undef __always_inline |
317 | # define __always_inline __inline |
318 | #endif |
319 | |
320 | /* Associate error messages with the source location of the call site rather |
321 | than with the source location inside the function. */ |
322 | #if __GNUC_PREREQ (4,3) |
323 | # define __attribute_artificial__ __attribute__ ((__artificial__)) |
324 | #else |
325 | # define __attribute_artificial__ /* Ignore */ |
326 | #endif |
327 | |
328 | /* GCC 4.3 and above with -std=c99 or -std=gnu99 implements ISO C99 |
329 | inline semantics, unless -fgnu89-inline is used. Using __GNUC_STDC_INLINE__ |
330 | or __GNUC_GNU_INLINE is not a good enough check for gcc because gcc versions |
331 | older than 4.3 may define these macros and still not guarantee GNU inlining |
332 | semantics. |
333 | |
334 | clang++ identifies itself as gcc-4.2, but has support for GNU inlining |
335 | semantics, that can be checked fot by using the __GNUC_STDC_INLINE_ and |
336 | __GNUC_GNU_INLINE__ macro definitions. */ |
337 | #if (!defined __cplusplus || __GNUC_PREREQ (4,3) \ |
338 | || (defined __clang__ && (defined __GNUC_STDC_INLINE__ \ |
339 | || defined __GNUC_GNU_INLINE__))) |
340 | # if defined __GNUC_STDC_INLINE__ || defined __cplusplus |
341 | # define __extern_inline extern __inline __attribute__ ((__gnu_inline__)) |
342 | # define __extern_always_inline \ |
343 | extern __always_inline __attribute__ ((__gnu_inline__)) |
344 | # else |
345 | # define __extern_inline extern __inline |
346 | # define __extern_always_inline extern __always_inline |
347 | # endif |
348 | #endif |
349 | |
350 | #ifdef __extern_always_inline |
351 | # define __fortify_function __extern_always_inline __attribute_artificial__ |
352 | #endif |
353 | |
354 | /* GCC 4.3 and above allow passing all anonymous arguments of an |
355 | __extern_always_inline function to some other vararg function. */ |
356 | #if __GNUC_PREREQ (4,3) |
357 | # define __va_arg_pack() __builtin_va_arg_pack () |
358 | # define __va_arg_pack_len() __builtin_va_arg_pack_len () |
359 | #endif |
360 | |
361 | /* It is possible to compile containing GCC extensions even if GCC is |
362 | run in pedantic mode if the uses are carefully marked using the |
363 | `__extension__' keyword. But this is not generally available before |
364 | version 2.8. */ |
365 | #if !__GNUC_PREREQ (2,8) |
366 | # define __extension__ /* Ignore */ |
367 | #endif |
368 | |
369 | /* __restrict is known in EGCS 1.2 and above. */ |
370 | #if !__GNUC_PREREQ (2,92) |
371 | # define __restrict /* Ignore */ |
372 | #endif |
373 | |
374 | /* ISO C99 also allows to declare arrays as non-overlapping. The syntax is |
375 | array_name[restrict] |
376 | GCC 3.1 supports this. */ |
377 | #if __GNUC_PREREQ (3,1) && !defined __GNUG__ |
378 | # define __restrict_arr __restrict |
379 | #else |
380 | # ifdef __GNUC__ |
381 | # define __restrict_arr /* Not supported in old GCC. */ |
382 | # else |
383 | # if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L |
384 | # define __restrict_arr restrict |
385 | # else |
386 | /* Some other non-C99 compiler. */ |
387 | # define __restrict_arr /* Not supported. */ |
388 | # endif |
389 | # endif |
390 | #endif |
391 | |
392 | #if __GNUC__ >= 3 |
393 | # define __glibc_unlikely(cond) __builtin_expect ((cond), 0) |
394 | # define __glibc_likely(cond) __builtin_expect ((cond), 1) |
395 | #else |
396 | # define __glibc_unlikely(cond) (cond) |
397 | # define __glibc_likely(cond) (cond) |
398 | #endif |
399 | |
400 | #if (!defined _Noreturn \ |
401 | && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \ |
402 | && !__GNUC_PREREQ (4,7)) |
403 | # if __GNUC_PREREQ (2,8) |
404 | # define _Noreturn __attribute__ ((__noreturn__)) |
405 | # else |
406 | # define _Noreturn |
407 | # endif |
408 | #endif |
409 | |
410 | #if __GNUC_PREREQ (8, 0) |
411 | /* Describes a char array whose address can safely be passed as the first |
412 | argument to strncpy and strncat, as the char array is not necessarily |
413 | a NUL-terminated string. */ |
414 | # define __attribute_nonstring__ __attribute__ ((__nonstring__)) |
415 | #else |
416 | # define __attribute_nonstring__ |
417 | #endif |
418 | |
419 | #if (!defined _Static_assert && !defined __cplusplus \ |
420 | && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \ |
421 | && (!__GNUC_PREREQ (4, 6) || defined __STRICT_ANSI__)) |
422 | # define _Static_assert(expr, diagnostic) \ |
423 | extern int (*__Static_assert_function (void)) \ |
424 | [!!sizeof (struct { int __error_if_negative: (expr) ? 2 : -1; })] |
425 | #endif |
426 | |
427 | #include <bits/wordsize.h> |
428 | #include <bits/long-double.h> |
429 | |
430 | #if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH |
431 | # define __LDBL_COMPAT 1 |
432 | # ifdef __REDIRECT |
433 | # define __LDBL_REDIR1(name, proto, alias) __REDIRECT (name, proto, alias) |
434 | # define __LDBL_REDIR(name, proto) \ |
435 | __LDBL_REDIR1 (name, proto, __nldbl_##name) |
436 | # define __LDBL_REDIR1_NTH(name, proto, alias) __REDIRECT_NTH (name, proto, alias) |
437 | # define __LDBL_REDIR_NTH(name, proto) \ |
438 | __LDBL_REDIR1_NTH (name, proto, __nldbl_##name) |
439 | # define __LDBL_REDIR1_DECL(name, alias) \ |
440 | extern __typeof (name) name __asm (__ASMNAME (#alias)); |
441 | # define __LDBL_REDIR_DECL(name) \ |
442 | extern __typeof (name) name __asm (__ASMNAME ("__nldbl_" #name)); |
443 | # define __REDIRECT_LDBL(name, proto, alias) \ |
444 | __LDBL_REDIR1 (name, proto, __nldbl_##alias) |
445 | # define __REDIRECT_NTH_LDBL(name, proto, alias) \ |
446 | __LDBL_REDIR1_NTH (name, proto, __nldbl_##alias) |
447 | # endif |
448 | #endif |
449 | #if !defined __LDBL_COMPAT || !defined __REDIRECT |
450 | # define __LDBL_REDIR1(name, proto, alias) name proto |
451 | # define __LDBL_REDIR(name, proto) name proto |
452 | # define __LDBL_REDIR1_NTH(name, proto, alias) name proto __THROW |
453 | # define __LDBL_REDIR_NTH(name, proto) name proto __THROW |
454 | # define __LDBL_REDIR_DECL(name) |
455 | # ifdef __REDIRECT |
456 | # define __REDIRECT_LDBL(name, proto, alias) __REDIRECT (name, proto, alias) |
457 | # define __REDIRECT_NTH_LDBL(name, proto, alias) \ |
458 | __REDIRECT_NTH (name, proto, alias) |
459 | # endif |
460 | #endif |
461 | |
462 | /* __glibc_macro_warning (MESSAGE) issues warning MESSAGE. This is |
463 | intended for use in preprocessor macros. |
464 | |
465 | Note: MESSAGE must be a _single_ string; concatenation of string |
466 | literals is not supported. */ |
467 | #if __GNUC_PREREQ (4,8) || __glibc_clang_prereq (3,5) |
468 | # define __glibc_macro_warning1(message) _Pragma (#message) |
469 | # define __glibc_macro_warning(message) \ |
470 | __glibc_macro_warning1 (GCC warning message) |
471 | #else |
472 | # define __glibc_macro_warning(msg) |
473 | #endif |
474 | |
475 | /* Generic selection (ISO C11) is a C-only feature, available in GCC |
476 | since version 4.9. Previous versions do not provide generic |
477 | selection, even though they might set __STDC_VERSION__ to 201112L, |
478 | when in -std=c11 mode. Thus, we must check for !defined __GNUC__ |
479 | when testing __STDC_VERSION__ for generic selection support. |
480 | On the other hand, Clang also defines __GNUC__, so a clang-specific |
481 | check is required to enable the use of generic selection. */ |
482 | #if !defined __cplusplus \ |
483 | && (__GNUC_PREREQ (4, 9) \ |
484 | || __glibc_clang_has_extension (c_generic_selections) \ |
485 | || (!defined __GNUC__ && defined __STDC_VERSION__ \ |
486 | && __STDC_VERSION__ >= 201112L)) |
487 | # define __HAVE_GENERIC_SELECTION 1 |
488 | #else |
489 | # define __HAVE_GENERIC_SELECTION 0 |
490 | #endif |
491 | |
492 | #endif /* sys/cdefs.h */ |
493 | |