| 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 | /* Fortify support. */ |
| 149 | #define __bos(ptr) __builtin_object_size (ptr, __USE_FORTIFY_LEVEL > 1) |
| 150 | #define __bos0(ptr) __builtin_object_size (ptr, 0) |
| 151 | |
| 152 | /* Use __builtin_dynamic_object_size at _FORTIFY_SOURCE=3 when available. */ |
| 153 | #if __USE_FORTIFY_LEVEL == 3 && (__glibc_clang_prereq (9, 0) \ |
| 154 | || __GNUC_PREREQ (12, 0)) |
| 155 | # define __glibc_objsize0(__o) __builtin_dynamic_object_size (__o, 0) |
| 156 | # define __glibc_objsize(__o) __builtin_dynamic_object_size (__o, 1) |
| 157 | #else |
| 158 | # define __glibc_objsize0(__o) __bos0 (__o) |
| 159 | # define __glibc_objsize(__o) __bos (__o) |
| 160 | #endif |
| 161 | |
| 162 | #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. */ |
| 166 | |
| 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)) |
| 171 | |
| 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)))) |
| 180 | |
| 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)) |
| 189 | |
| 190 | /* Fortify function f. __f_alias, __f_chk and __f_chk_warn must be |
| 191 | declared. */ |
| 192 | |
| 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))) |
| 199 | |
| 200 | /* Fortify function f, where object size argument passed to f is the number of |
| 201 | elements and not total size. */ |
| 202 | |
| 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 |
| 210 | |
| 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 |
| 219 | |
| 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 |
| 242 | |
| 243 | |
| 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). |
| 250 | |
| 251 | Example: |
| 252 | int __REDIRECT(setpgrp, (__pid_t pid, __pid_t pgrp), setpgid); */ |
| 253 | |
| 254 | #if (defined __GNUC__ && __GNUC__ >= 2) || (__clang_major__ >= 4) |
| 255 | |
| 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 |
| 270 | |
| 271 | #ifndef __REDIRECT_FORTIFY |
| 272 | #define __REDIRECT_FORTIFY __REDIRECT |
| 273 | #endif |
| 274 | |
| 275 | #ifndef __REDIRECT_FORTIFY_NTH |
| 276 | #define __REDIRECT_FORTIFY_NTH __REDIRECT_NTH |
| 277 | #endif |
| 278 | |
| 279 | /* |
| 280 | #elif __SOME_OTHER_COMPILER__ |
| 281 | |
| 282 | # define __REDIRECT(name, proto, alias) name proto; \ |
| 283 | _Pragma("let " #name " = " #alias) |
| 284 | */ |
| 285 | #endif |
| 286 | |
| 287 | /* GCC and clang have various useful declarations that can be made with |
| 288 | the '__attribute__' syntax. All of the ways we use this do fine if |
| 289 | they are omitted for compilers that don't understand it. */ |
| 290 | #if !(defined __GNUC__ || defined __clang__) |
| 291 | # define __attribute__(xyz) /* Ignore */ |
| 292 | #endif |
| 293 | |
| 294 | /* At some point during the gcc 2.96 development the `malloc' attribute |
| 295 | for functions was introduced. We don't want to use it unconditionally |
| 296 | (although this would be possible) since it generates warnings. */ |
| 297 | #if __GNUC_PREREQ (2,96) || __glibc_has_attribute (__malloc__) |
| 298 | # define __attribute_malloc__ __attribute__ ((__malloc__)) |
| 299 | #else |
| 300 | # define __attribute_malloc__ /* Ignore */ |
| 301 | #endif |
| 302 | |
| 303 | /* Tell the compiler which arguments to an allocation function |
| 304 | indicate the size of the allocation. */ |
| 305 | #if __GNUC_PREREQ (4, 3) |
| 306 | # define __attribute_alloc_size__(params) \ |
| 307 | __attribute__ ((__alloc_size__ params)) |
| 308 | #else |
| 309 | # define __attribute_alloc_size__(params) /* Ignore. */ |
| 310 | #endif |
| 311 | |
| 312 | /* Tell the compiler which argument to an allocation function |
| 313 | indicates the alignment of the allocation. */ |
| 314 | #if __GNUC_PREREQ (4, 9) || __glibc_has_attribute (__alloc_align__) |
| 315 | # define __attribute_alloc_align__(param) \ |
| 316 | __attribute__ ((__alloc_align__ param)) |
| 317 | #else |
| 318 | # define __attribute_alloc_align__(param) /* Ignore. */ |
| 319 | #endif |
| 320 | |
| 321 | /* At some point during the gcc 2.96 development the `pure' attribute |
| 322 | for functions was introduced. We don't want to use it unconditionally |
| 323 | (although this would be possible) since it generates warnings. */ |
| 324 | #if __GNUC_PREREQ (2,96) || __glibc_has_attribute (__pure__) |
| 325 | # define __attribute_pure__ __attribute__ ((__pure__)) |
| 326 | #else |
| 327 | # define __attribute_pure__ /* Ignore */ |
| 328 | #endif |
| 329 | |
| 330 | /* This declaration tells the compiler that the value is constant. */ |
| 331 | #if __GNUC_PREREQ (2,5) || __glibc_has_attribute (__const__) |
| 332 | # define __attribute_const__ __attribute__ ((__const__)) |
| 333 | #else |
| 334 | # define __attribute_const__ /* Ignore */ |
| 335 | #endif |
| 336 | |
| 337 | #if __GNUC_PREREQ (2,7) || __glibc_has_attribute (__unused__) |
| 338 | # define __attribute_maybe_unused__ __attribute__ ((__unused__)) |
| 339 | #else |
| 340 | # define __attribute_maybe_unused__ /* Ignore */ |
| 341 | #endif |
| 342 | |
| 343 | /* At some point during the gcc 3.1 development the `used' attribute |
| 344 | for functions was introduced. We don't want to use it unconditionally |
| 345 | (although this would be possible) since it generates warnings. */ |
| 346 | #if __GNUC_PREREQ (3,1) || __glibc_has_attribute (__used__) |
| 347 | # define __attribute_used__ __attribute__ ((__used__)) |
| 348 | # define __attribute_noinline__ __attribute__ ((__noinline__)) |
| 349 | #else |
| 350 | # define __attribute_used__ __attribute__ ((__unused__)) |
| 351 | # define __attribute_noinline__ /* Ignore */ |
| 352 | #endif |
| 353 | |
| 354 | /* Since version 3.2, gcc allows marking deprecated functions. */ |
| 355 | #if __GNUC_PREREQ (3,2) || __glibc_has_attribute (__deprecated__) |
| 356 | # define __attribute_deprecated__ __attribute__ ((__deprecated__)) |
| 357 | #else |
| 358 | # define __attribute_deprecated__ /* Ignore */ |
| 359 | #endif |
| 360 | |
| 361 | /* Since version 4.5, gcc also allows one to specify the message printed |
| 362 | when a deprecated function is used. clang claims to be gcc 4.2, but |
| 363 | may also support this feature. */ |
| 364 | #if __GNUC_PREREQ (4,5) \ |
| 365 | || __glibc_has_extension (__attribute_deprecated_with_message__) |
| 366 | # define __attribute_deprecated_msg__(msg) \ |
| 367 | __attribute__ ((__deprecated__ (msg))) |
| 368 | #else |
| 369 | # define __attribute_deprecated_msg__(msg) __attribute_deprecated__ |
| 370 | #endif |
| 371 | |
| 372 | /* At some point during the gcc 2.8 development the `format_arg' attribute |
| 373 | for functions was introduced. We don't want to use it unconditionally |
| 374 | (although this would be possible) since it generates warnings. |
| 375 | If several `format_arg' attributes are given for the same function, in |
| 376 | gcc-3.0 and older, all but the last one are ignored. In newer gccs, |
| 377 | all designated arguments are considered. */ |
| 378 | #if __GNUC_PREREQ (2,8) || __glibc_has_attribute (__format_arg__) |
| 379 | # define __attribute_format_arg__(x) __attribute__ ((__format_arg__ (x))) |
| 380 | #else |
| 381 | # define __attribute_format_arg__(x) /* Ignore */ |
| 382 | #endif |
| 383 | |
| 384 | /* At some point during the gcc 2.97 development the `strfmon' format |
| 385 | attribute for functions was introduced. We don't want to use it |
| 386 | unconditionally (although this would be possible) since it |
| 387 | generates warnings. */ |
| 388 | #if __GNUC_PREREQ (2,97) || __glibc_has_attribute (__format__) |
| 389 | # define __attribute_format_strfmon__(a,b) \ |
| 390 | __attribute__ ((__format__ (__strfmon__, a, b))) |
| 391 | #else |
| 392 | # define __attribute_format_strfmon__(a,b) /* Ignore */ |
| 393 | #endif |
| 394 | |
| 395 | /* The nonnull function attribute marks pointer parameters that |
| 396 | must not be NULL. This has the name __nonnull in glibc, |
| 397 | and __attribute_nonnull__ in files shared with Gnulib to avoid |
| 398 | collision with a different __nonnull in DragonFlyBSD 5.9. */ |
| 399 | #ifndef __attribute_nonnull__ |
| 400 | # if __GNUC_PREREQ (3,3) || __glibc_has_attribute (__nonnull__) |
| 401 | # define __attribute_nonnull__(params) __attribute__ ((__nonnull__ params)) |
| 402 | # else |
| 403 | # define __attribute_nonnull__(params) |
| 404 | # endif |
| 405 | #endif |
| 406 | #ifndef __nonnull |
| 407 | # define __nonnull(params) __attribute_nonnull__ (params) |
| 408 | #endif |
| 409 | |
| 410 | /* The returns_nonnull function attribute marks the return type of the function |
| 411 | as always being non-null. */ |
| 412 | #ifndef __returns_nonnull |
| 413 | # if __GNUC_PREREQ (4, 9) || __glibc_has_attribute (__returns_nonnull__) |
| 414 | # define __returns_nonnull __attribute__ ((__returns_nonnull__)) |
| 415 | # else |
| 416 | # define __returns_nonnull |
| 417 | # endif |
| 418 | #endif |
| 419 | |
| 420 | /* If fortification mode, we warn about unused results of certain |
| 421 | function calls which can lead to problems. */ |
| 422 | #if __GNUC_PREREQ (3,4) || __glibc_has_attribute (__warn_unused_result__) |
| 423 | # define __attribute_warn_unused_result__ \ |
| 424 | __attribute__ ((__warn_unused_result__)) |
| 425 | # if defined __USE_FORTIFY_LEVEL && __USE_FORTIFY_LEVEL > 0 |
| 426 | # define __wur __attribute_warn_unused_result__ |
| 427 | # endif |
| 428 | #else |
| 429 | # define __attribute_warn_unused_result__ /* empty */ |
| 430 | #endif |
| 431 | #ifndef __wur |
| 432 | # define __wur /* Ignore */ |
| 433 | #endif |
| 434 | |
| 435 | /* Forces a function to be always inlined. */ |
| 436 | #if __GNUC_PREREQ (3,2) || __glibc_has_attribute (__always_inline__) |
| 437 | /* The Linux kernel defines __always_inline in stddef.h (283d7573), and |
| 438 | it conflicts with this definition. Therefore undefine it first to |
| 439 | allow either header to be included first. */ |
| 440 | # undef __always_inline |
| 441 | # define __always_inline __inline __attribute__ ((__always_inline__)) |
| 442 | #else |
| 443 | # undef __always_inline |
| 444 | # define __always_inline __inline |
| 445 | #endif |
| 446 | |
| 447 | /* Associate error messages with the source location of the call site rather |
| 448 | than with the source location inside the function. */ |
| 449 | #if __GNUC_PREREQ (4,3) || __glibc_has_attribute (__artificial__) |
| 450 | # define __attribute_artificial__ __attribute__ ((__artificial__)) |
| 451 | #else |
| 452 | # define __attribute_artificial__ /* Ignore */ |
| 453 | #endif |
| 454 | |
| 455 | /* GCC 4.3 and above with -std=c99 or -std=gnu99 implements ISO C99 |
| 456 | inline semantics, unless -fgnu89-inline is used. Using __GNUC_STDC_INLINE__ |
| 457 | or __GNUC_GNU_INLINE is not a good enough check for gcc because gcc versions |
| 458 | older than 4.3 may define these macros and still not guarantee GNU inlining |
| 459 | semantics. |
| 460 | |
| 461 | clang++ identifies itself as gcc-4.2, but has support for GNU inlining |
| 462 | semantics, that can be checked for by using the __GNUC_STDC_INLINE_ and |
| 463 | __GNUC_GNU_INLINE__ macro definitions. */ |
| 464 | #if (!defined __cplusplus || __GNUC_PREREQ (4,3) \ |
| 465 | || (defined __clang__ && (defined __GNUC_STDC_INLINE__ \ |
| 466 | || defined __GNUC_GNU_INLINE__))) |
| 467 | # if defined __GNUC_STDC_INLINE__ || defined __cplusplus |
| 468 | # define __extern_inline extern __inline __attribute__ ((__gnu_inline__)) |
| 469 | # define __extern_always_inline \ |
| 470 | extern __always_inline __attribute__ ((__gnu_inline__)) |
| 471 | # else |
| 472 | # define __extern_inline extern __inline |
| 473 | # define __extern_always_inline extern __always_inline |
| 474 | # endif |
| 475 | #endif |
| 476 | |
| 477 | #ifdef __extern_always_inline |
| 478 | # define __fortify_function __extern_always_inline __attribute_artificial__ |
| 479 | #endif |
| 480 | |
| 481 | /* GCC 4.3 and above allow passing all anonymous arguments of an |
| 482 | __extern_always_inline function to some other vararg function. */ |
| 483 | #if __GNUC_PREREQ (4,3) |
| 484 | # define __va_arg_pack() __builtin_va_arg_pack () |
| 485 | # define __va_arg_pack_len() __builtin_va_arg_pack_len () |
| 486 | #endif |
| 487 | |
| 488 | /* It is possible to compile containing GCC extensions even if GCC is |
| 489 | run in pedantic mode if the uses are carefully marked using the |
| 490 | `__extension__' keyword. But this is not generally available before |
| 491 | version 2.8. */ |
| 492 | #if !(__GNUC_PREREQ (2,8) || defined __clang__) |
| 493 | # define __extension__ /* Ignore */ |
| 494 | #endif |
| 495 | |
| 496 | /* __restrict is known in EGCS 1.2 and above, and in clang. |
| 497 | It works also in C++ mode (outside of arrays), but only when spelled |
| 498 | as '__restrict', not 'restrict'. */ |
| 499 | #if !(__GNUC_PREREQ (2,92) || __clang_major__ >= 3) |
| 500 | # if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L |
| 501 | # define __restrict restrict |
| 502 | # else |
| 503 | # define __restrict /* Ignore */ |
| 504 | # endif |
| 505 | #endif |
| 506 | |
| 507 | /* ISO C99 also allows to declare arrays as non-overlapping. The syntax is |
| 508 | array_name[restrict] |
| 509 | GCC 3.1 and clang support this. |
| 510 | This syntax is not usable in C++ mode. */ |
| 511 | #if (__GNUC_PREREQ (3,1) || __clang_major__ >= 3) && !defined __cplusplus |
| 512 | # define __restrict_arr __restrict |
| 513 | #else |
| 514 | # ifdef __GNUC__ |
| 515 | # define __restrict_arr /* Not supported in old GCC. */ |
| 516 | # else |
| 517 | # if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L |
| 518 | # define __restrict_arr restrict |
| 519 | # else |
| 520 | /* Some other non-C99 compiler. */ |
| 521 | # define __restrict_arr /* Not supported. */ |
| 522 | # endif |
| 523 | # endif |
| 524 | #endif |
| 525 | |
| 526 | #if (__GNUC__ >= 3) || __glibc_has_builtin (__builtin_expect) |
| 527 | # define __glibc_unlikely(cond) __builtin_expect ((cond), 0) |
| 528 | # define __glibc_likely(cond) __builtin_expect ((cond), 1) |
| 529 | #else |
| 530 | # define __glibc_unlikely(cond) (cond) |
| 531 | # define __glibc_likely(cond) (cond) |
| 532 | #endif |
| 533 | |
| 534 | #if (!defined _Noreturn \ |
| 535 | && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \ |
| 536 | && !(__GNUC_PREREQ (4,7) \ |
| 537 | || (3 < __clang_major__ + (5 <= __clang_minor__)))) |
| 538 | # if __GNUC_PREREQ (2,8) |
| 539 | # define _Noreturn __attribute__ ((__noreturn__)) |
| 540 | # else |
| 541 | # define _Noreturn |
| 542 | # endif |
| 543 | #endif |
| 544 | |
| 545 | #if __GNUC_PREREQ (8, 0) |
| 546 | /* Describes a char array whose address can safely be passed as the first |
| 547 | argument to strncpy and strncat, as the char array is not necessarily |
| 548 | a NUL-terminated string. */ |
| 549 | # define __attribute_nonstring__ __attribute__ ((__nonstring__)) |
| 550 | #else |
| 551 | # define __attribute_nonstring__ |
| 552 | #endif |
| 553 | |
| 554 | /* Undefine (also defined in libc-symbols.h). */ |
| 555 | #undef __attribute_copy__ |
| 556 | #if __GNUC_PREREQ (9, 0) |
| 557 | /* Copies attributes from the declaration or type referenced by |
| 558 | the argument. */ |
| 559 | # define __attribute_copy__(arg) __attribute__ ((__copy__ (arg))) |
| 560 | #else |
| 561 | # define __attribute_copy__(arg) |
| 562 | #endif |
| 563 | |
| 564 | #if (!defined _Static_assert && !defined __cplusplus \ |
| 565 | && (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0) < 201112 \ |
| 566 | && (!(__GNUC_PREREQ (4, 6) || __clang_major__ >= 4) \ |
| 567 | || defined __STRICT_ANSI__)) |
| 568 | # define _Static_assert(expr, diagnostic) \ |
| 569 | extern int (*__Static_assert_function (void)) \ |
| 570 | [!!sizeof (struct { int __error_if_negative: (expr) ? 2 : -1; })] |
| 571 | #endif |
| 572 | |
| 573 | /* Gnulib avoids including these, as they don't work on non-glibc or |
| 574 | older glibc platforms. */ |
| 575 | #ifndef __GNULIB_CDEFS |
| 576 | # include <bits/wordsize.h> |
| 577 | # include <bits/long-double.h> |
| 578 | #endif |
| 579 | |
| 580 | #if __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 1 |
| 581 | # ifdef __REDIRECT |
| 582 | |
| 583 | /* Alias name defined automatically. */ |
| 584 | # define __LDBL_REDIR(name, proto) ... unused__ldbl_redir |
| 585 | # define __LDBL_REDIR_DECL(name) \ |
| 586 | extern __typeof (name) name __asm (__ASMNAME ("__" #name "ieee128")); |
| 587 | # define __REDIRECT_LDBL(name, proto, alias) \ |
| 588 | name proto __asm (__ASMNAME ("__" #alias "ieee128")) |
| 589 | |
| 590 | /* Alias name defined automatically, with leading underscores. */ |
| 591 | # define __LDBL_REDIR2_DECL(name) \ |
| 592 | extern __typeof (__##name) __##name \ |
| 593 | __asm (__ASMNAME ("__" #name "ieee128")); |
| 594 | |
| 595 | /* Alias name defined manually. */ |
| 596 | # define __LDBL_REDIR1(name, proto, alias) ... unused__ldbl_redir1 |
| 597 | # define __LDBL_REDIR1_DECL(name, alias) \ |
| 598 | extern __typeof (name) name __asm (__ASMNAME (#alias)); |
| 599 | |
| 600 | # define __LDBL_REDIR1_NTH(name, proto, alias) \ |
| 601 | __REDIRECT_NTH (name, proto, alias) |
| 602 | # define __REDIRECT_NTH_LDBL(name, proto, alias) \ |
| 603 | __LDBL_REDIR1_NTH (name, proto, __##alias##ieee128) |
| 604 | |
| 605 | /* Unused. */ |
| 606 | # define __LDBL_REDIR_NTH(name, proto) ... unused__ldbl_redir_nth |
| 607 | |
| 608 | # else |
| 609 | _Static_assert (0, "IEEE 128-bits long double requires redirection on this platform" ); |
| 610 | # endif |
| 611 | #elif defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH |
| 612 | # define __LDBL_COMPAT 1 |
| 613 | # ifdef __REDIRECT |
| 614 | # define __LDBL_REDIR1(name, proto, alias) __REDIRECT (name, proto, alias) |
| 615 | # define __LDBL_REDIR(name, proto) \ |
| 616 | __LDBL_REDIR1 (name, proto, __nldbl_##name) |
| 617 | # define __LDBL_REDIR1_NTH(name, proto, alias) __REDIRECT_NTH (name, proto, alias) |
| 618 | # define __LDBL_REDIR_NTH(name, proto) \ |
| 619 | __LDBL_REDIR1_NTH (name, proto, __nldbl_##name) |
| 620 | # define __LDBL_REDIR2_DECL(name) \ |
| 621 | extern __typeof (__##name) __##name __asm (__ASMNAME ("__nldbl___" #name)); |
| 622 | # define __LDBL_REDIR1_DECL(name, alias) \ |
| 623 | extern __typeof (name) name __asm (__ASMNAME (#alias)); |
| 624 | # define __LDBL_REDIR_DECL(name) \ |
| 625 | extern __typeof (name) name __asm (__ASMNAME ("__nldbl_" #name)); |
| 626 | # define __REDIRECT_LDBL(name, proto, alias) \ |
| 627 | __LDBL_REDIR1 (name, proto, __nldbl_##alias) |
| 628 | # define __REDIRECT_NTH_LDBL(name, proto, alias) \ |
| 629 | __LDBL_REDIR1_NTH (name, proto, __nldbl_##alias) |
| 630 | # endif |
| 631 | #endif |
| 632 | #if (!defined __LDBL_COMPAT && __LDOUBLE_REDIRECTS_TO_FLOAT128_ABI == 0) \ |
| 633 | || !defined __REDIRECT |
| 634 | # define __LDBL_REDIR1(name, proto, alias) name proto |
| 635 | # define __LDBL_REDIR(name, proto) name proto |
| 636 | # define __LDBL_REDIR1_NTH(name, proto, alias) name proto __THROW |
| 637 | # define __LDBL_REDIR_NTH(name, proto) name proto __THROW |
| 638 | # define __LDBL_REDIR2_DECL(name) |
| 639 | # define __LDBL_REDIR_DECL(name) |
| 640 | # ifdef __REDIRECT |
| 641 | # define __REDIRECT_LDBL(name, proto, alias) __REDIRECT (name, proto, alias) |
| 642 | # define __REDIRECT_NTH_LDBL(name, proto, alias) \ |
| 643 | __REDIRECT_NTH (name, proto, alias) |
| 644 | # endif |
| 645 | #endif |
| 646 | |
| 647 | /* __glibc_macro_warning (MESSAGE) issues warning MESSAGE. This is |
| 648 | intended for use in preprocessor macros. |
| 649 | |
| 650 | Note: MESSAGE must be a _single_ string; concatenation of string |
| 651 | literals is not supported. */ |
| 652 | #if __GNUC_PREREQ (4,8) || __glibc_clang_prereq (3,5) |
| 653 | # define __glibc_macro_warning1(message) _Pragma (#message) |
| 654 | # define __glibc_macro_warning(message) \ |
| 655 | __glibc_macro_warning1 (GCC warning message) |
| 656 | #else |
| 657 | # define __glibc_macro_warning(msg) |
| 658 | #endif |
| 659 | |
| 660 | /* Generic selection (ISO C11) is a C-only feature, available in GCC |
| 661 | since version 4.9. Previous versions do not provide generic |
| 662 | selection, even though they might set __STDC_VERSION__ to 201112L, |
| 663 | when in -std=c11 mode. Thus, we must check for !defined __GNUC__ |
| 664 | when testing __STDC_VERSION__ for generic selection support. |
| 665 | On the other hand, Clang also defines __GNUC__, so a clang-specific |
| 666 | check is required to enable the use of generic selection. */ |
| 667 | #if !defined __cplusplus \ |
| 668 | && (__GNUC_PREREQ (4, 9) \ |
| 669 | || __glibc_has_extension (c_generic_selections) \ |
| 670 | || (!defined __GNUC__ && defined __STDC_VERSION__ \ |
| 671 | && __STDC_VERSION__ >= 201112L)) |
| 672 | # define __HAVE_GENERIC_SELECTION 1 |
| 673 | #else |
| 674 | # define __HAVE_GENERIC_SELECTION 0 |
| 675 | #endif |
| 676 | |
| 677 | #if __GNUC_PREREQ (10, 0) |
| 678 | /* Designates a 1-based positional argument ref-index of pointer type |
| 679 | that can be used to access size-index elements of the pointed-to |
| 680 | array according to access mode, or at least one element when |
| 681 | size-index is not provided: |
| 682 | access (access-mode, <ref-index> [, <size-index>]) */ |
| 683 | # define __attr_access(x) __attribute__ ((__access__ x)) |
| 684 | /* For _FORTIFY_SOURCE == 3 we use __builtin_dynamic_object_size, which may |
| 685 | use the access attribute to get object sizes from function definition |
| 686 | arguments, so we can't use them on functions we fortify. Drop the object |
| 687 | size hints for such functions. */ |
| 688 | # if __USE_FORTIFY_LEVEL == 3 |
| 689 | # define __fortified_attr_access(a, o, s) __attribute__ ((__access__ (a, o))) |
| 690 | # else |
| 691 | # define __fortified_attr_access(a, o, s) __attr_access ((a, o, s)) |
| 692 | # endif |
| 693 | # if __GNUC_PREREQ (11, 0) |
| 694 | # define __attr_access_none(argno) __attribute__ ((__access__ (__none__, argno))) |
| 695 | # else |
| 696 | # define __attr_access_none(argno) |
| 697 | # endif |
| 698 | #else |
| 699 | # define __fortified_attr_access(a, o, s) |
| 700 | # define __attr_access(x) |
| 701 | # define __attr_access_none(argno) |
| 702 | #endif |
| 703 | |
| 704 | #if __GNUC_PREREQ (11, 0) |
| 705 | /* Designates dealloc as a function to call to deallocate objects |
| 706 | allocated by the declared function. */ |
| 707 | # define __attr_dealloc(dealloc, argno) \ |
| 708 | __attribute__ ((__malloc__ (dealloc, argno))) |
| 709 | # define __attr_dealloc_free __attr_dealloc (__builtin_free, 1) |
| 710 | #else |
| 711 | # define __attr_dealloc(dealloc, argno) |
| 712 | # define __attr_dealloc_free |
| 713 | #endif |
| 714 | |
| 715 | /* Specify that a function such as setjmp or vfork may return |
| 716 | twice. */ |
| 717 | #if __GNUC_PREREQ (4, 1) |
| 718 | # define __attribute_returns_twice__ __attribute__ ((__returns_twice__)) |
| 719 | #else |
| 720 | # define __attribute_returns_twice__ /* Ignore. */ |
| 721 | #endif |
| 722 | |
| 723 | #endif /* sys/cdefs.h */ |
| 724 | |