1 /*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Berkeley Software Design, Inc. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#)cdefs.h 8.8 (Berkeley) 1/9/95 33 * $FreeBSD$ 34 */ 35 36 #ifndef _SYS_CDEFS_H_ 37 #define _SYS_CDEFS_H_ 38 39 /* 40 * Testing against Clang-specific extensions. 41 */ 42 #ifndef __has_attribute 43 #define __has_attribute(x) 0 44 #endif 45 #ifndef __has_extension 46 #define __has_extension __has_feature 47 #endif 48 #ifndef __has_feature 49 #define __has_feature(x) 0 50 #endif 51 #ifndef __has_include 52 #define __has_include(x) 0 53 #endif 54 #ifndef __has_builtin 55 #define __has_builtin(x) 0 56 #endif 57 58 #if defined(__cplusplus) 59 #define __BEGIN_DECLS extern "C" { 60 #define __END_DECLS } 61 #else 62 #define __BEGIN_DECLS 63 #define __END_DECLS 64 #endif 65 66 /* 67 * This code has been put in place to help reduce the addition of 68 * compiler specific defines in FreeBSD code. It helps to aid in 69 * having a compiler-agnostic source tree. 70 */ 71 72 #if defined(__GNUC__) || defined(__INTEL_COMPILER) 73 74 #if __GNUC__ >= 3 || defined(__INTEL_COMPILER) 75 #define __GNUCLIKE_ASM 3 76 #define __GNUCLIKE_MATH_BUILTIN_CONSTANTS 77 #else 78 #define __GNUCLIKE_ASM 2 79 #endif 80 #define __GNUCLIKE___TYPEOF 1 81 #define __GNUCLIKE___OFFSETOF 1 82 #define __GNUCLIKE___SECTION 1 83 84 #ifndef __INTEL_COMPILER 85 #define __GNUCLIKE_CTOR_SECTION_HANDLING 1 86 #endif 87 88 #define __GNUCLIKE_BUILTIN_CONSTANT_P 1 89 #if defined(__INTEL_COMPILER) && defined(__cplusplus) && \ 90 __INTEL_COMPILER < 800 91 #undef __GNUCLIKE_BUILTIN_CONSTANT_P 92 #endif 93 94 #if (__GNUC_MINOR__ > 95 || __GNUC__ >= 3) 95 #define __GNUCLIKE_BUILTIN_VARARGS 1 96 #define __GNUCLIKE_BUILTIN_STDARG 1 97 #define __GNUCLIKE_BUILTIN_VAALIST 1 98 #endif 99 100 #if defined(__GNUC__) 101 #define __GNUC_VA_LIST_COMPATIBILITY 1 102 #endif 103 104 /* 105 * Compiler memory barriers, specific to gcc and clang. 106 */ 107 #if defined(__GNUC__) 108 #define __compiler_membar() __asm __volatile(" " : : : "memory") 109 #endif 110 111 #ifndef __INTEL_COMPILER 112 #define __GNUCLIKE_BUILTIN_NEXT_ARG 1 113 #define __GNUCLIKE_MATH_BUILTIN_RELOPS 114 #endif 115 116 #define __GNUCLIKE_BUILTIN_MEMCPY 1 117 118 /* XXX: if __GNUC__ >= 2: not tested everywhere originally, where replaced */ 119 #define __CC_SUPPORTS_INLINE 1 120 #define __CC_SUPPORTS___INLINE 1 121 #define __CC_SUPPORTS___INLINE__ 1 122 123 #define __CC_SUPPORTS___FUNC__ 1 124 #define __CC_SUPPORTS_WARNING 1 125 126 #define __CC_SUPPORTS_VARADIC_XXX 1 /* see varargs.h */ 127 128 #define __CC_SUPPORTS_DYNAMIC_ARRAY_INIT 1 129 130 #endif /* __GNUC__ || __INTEL_COMPILER */ 131 132 /* 133 * Macro to test if we're using a specific version of gcc or later. 134 */ 135 #if defined(__GNUC__) && !defined(__INTEL_COMPILER) 136 #define __GNUC_PREREQ__(ma, mi) \ 137 (__GNUC__ > (ma) || __GNUC__ == (ma) && __GNUC_MINOR__ >= (mi)) 138 #else 139 #define __GNUC_PREREQ__(ma, mi) 0 140 #endif 141 142 /* 143 * The __CONCAT macro is used to concatenate parts of symbol names, e.g. 144 * with "#define OLD(foo) __CONCAT(old,foo)", OLD(foo) produces oldfoo. 145 * The __CONCAT macro is a bit tricky to use if it must work in non-ANSI 146 * mode -- there must be no spaces between its arguments, and for nested 147 * __CONCAT's, all the __CONCAT's must be at the left. __CONCAT can also 148 * concatenate double-quoted strings produced by the __STRING macro, but 149 * this only works with ANSI C. 150 * 151 * __XSTRING is like __STRING, but it expands any macros in its argument 152 * first. It is only available with ANSI C. 153 */ 154 #if defined(__STDC__) || defined(__cplusplus) 155 #define __P(protos) protos /* full-blown ANSI C */ 156 #define __CONCAT1(x,y) x ## y 157 #define __CONCAT(x,y) __CONCAT1(x,y) 158 #define __STRING(x) #x /* stringify without expanding x */ 159 #define __XSTRING(x) __STRING(x) /* expand x, then stringify */ 160 161 #define __const const /* define reserved names to standard */ 162 #define __signed signed 163 #define __volatile volatile 164 #if defined(__cplusplus) 165 #define __inline inline /* convert to C++ keyword */ 166 #else 167 #if !(defined(__CC_SUPPORTS___INLINE)) 168 #define __inline /* delete GCC keyword */ 169 #endif /* ! __CC_SUPPORTS___INLINE */ 170 #endif /* !__cplusplus */ 171 172 #else /* !(__STDC__ || __cplusplus) */ 173 #define __P(protos) () /* traditional C preprocessor */ 174 #define __CONCAT(x,y) x/**/y 175 #define __STRING(x) "x" 176 177 #if !defined(__CC_SUPPORTS___INLINE) 178 #define __const /* delete pseudo-ANSI C keywords */ 179 #define __inline 180 #define __signed 181 #define __volatile 182 /* 183 * In non-ANSI C environments, new programs will want ANSI-only C keywords 184 * deleted from the program and old programs will want them left alone. 185 * When using a compiler other than gcc, programs using the ANSI C keywords 186 * const, inline etc. as normal identifiers should define -DNO_ANSI_KEYWORDS. 187 * When using "gcc -traditional", we assume that this is the intent; if 188 * __GNUC__ is defined but __STDC__ is not, we leave the new keywords alone. 189 */ 190 #ifndef NO_ANSI_KEYWORDS 191 #define const /* delete ANSI C keywords */ 192 #define inline 193 #define signed 194 #define volatile 195 #endif /* !NO_ANSI_KEYWORDS */ 196 #endif /* !__CC_SUPPORTS___INLINE */ 197 #endif /* !(__STDC__ || __cplusplus) */ 198 199 /* 200 * Compiler-dependent macros to help declare dead (non-returning) and 201 * pure (no side effects) functions, and unused variables. They are 202 * null except for versions of gcc that are known to support the features 203 * properly (old versions of gcc-2 supported the dead and pure features 204 * in a different (wrong) way). If we do not provide an implementation 205 * for a given compiler, let the compile fail if it is told to use 206 * a feature that we cannot live without. 207 */ 208 #ifdef lint 209 #define __dead2 210 #define __pure2 211 #define __unused 212 #define __packed 213 #define __aligned(x) 214 #define __alloc_align(x) 215 #define __alloc_size(x) 216 #define __section(x) 217 #define __weak_symbol 218 #else 219 #define __weak_symbol __attribute__((__weak__)) 220 #if !__GNUC_PREREQ__(2, 5) && !defined(__INTEL_COMPILER) 221 #define __dead2 222 #define __pure2 223 #define __unused 224 #endif 225 #if __GNUC__ == 2 && __GNUC_MINOR__ >= 5 && __GNUC_MINOR__ < 7 && !defined(__INTEL_COMPILER) 226 #define __dead2 __attribute__((__noreturn__)) 227 #define __pure2 __attribute__((__const__)) 228 #define __unused 229 /* XXX Find out what to do for __packed, __aligned and __section */ 230 #endif 231 #if __GNUC_PREREQ__(2, 7) || defined(__INTEL_COMPILER) 232 #define __dead2 __attribute__((__noreturn__)) 233 #define __pure2 __attribute__((__const__)) 234 #define __unused __attribute__((__unused__)) 235 #define __used __attribute__((__used__)) 236 #define __packed __attribute__((__packed__)) 237 #define __aligned(x) __attribute__((__aligned__(x))) 238 #define __section(x) __attribute__((__section__(x))) 239 #endif 240 #if __GNUC_PREREQ__(4, 3) || __has_attribute(__alloc_size__) 241 #define __alloc_size(x) __attribute__((__alloc_size__(x))) 242 #define __alloc_size2(n, x) __attribute__((__alloc_size__(n, x))) 243 #else 244 #define __alloc_size(x) 245 #define __alloc_size2(n, x) 246 #endif 247 #if __GNUC_PREREQ__(4, 9) || __has_attribute(__alloc_align__) 248 #define __alloc_align(x) __attribute__((__alloc_align__(x))) 249 #else 250 #define __alloc_align(x) 251 #endif 252 #endif /* lint */ 253 254 #if !__GNUC_PREREQ__(2, 95) 255 #define __alignof(x) __offsetof(struct { char __a; x __b; }, __b) 256 #endif 257 258 /* 259 * Keywords added in C11. 260 */ 261 262 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 201112L || defined(lint) 263 264 #if !__has_extension(c_alignas) 265 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \ 266 __has_extension(cxx_alignas) 267 #define _Alignas(x) alignas(x) 268 #else 269 /* XXX: Only emulates _Alignas(constant-expression); not _Alignas(type-name). */ 270 #define _Alignas(x) __aligned(x) 271 #endif 272 #endif 273 274 #if defined(__cplusplus) && __cplusplus >= 201103L 275 #define _Alignof(x) alignof(x) 276 #else 277 #define _Alignof(x) __alignof(x) 278 #endif 279 280 #if !__has_extension(c_atomic) && !__has_extension(cxx_atomic) 281 /* 282 * No native support for _Atomic(). Place object in structure to prevent 283 * most forms of direct non-atomic access. 284 */ 285 #define _Atomic(T) struct { T volatile __val; } 286 #endif 287 288 #if defined(__cplusplus) && __cplusplus >= 201103L 289 #define _Noreturn [[noreturn]] 290 #else 291 #define _Noreturn __dead2 292 #endif 293 294 #if !__has_extension(c_static_assert) 295 #if (defined(__cplusplus) && __cplusplus >= 201103L) || \ 296 __has_extension(cxx_static_assert) 297 #define _Static_assert(x, y) static_assert(x, y) 298 #elif __GNUC_PREREQ__(4,6) 299 /* Nothing, gcc 4.6 and higher has _Static_assert built-in */ 300 #elif defined(__COUNTER__) 301 #define _Static_assert(x, y) __Static_assert(x, __COUNTER__) 302 #define __Static_assert(x, y) ___Static_assert(x, y) 303 #define ___Static_assert(x, y) typedef char __assert_ ## y[(x) ? 1 : -1] \ 304 __unused 305 #else 306 #define _Static_assert(x, y) struct __hack 307 #endif 308 #endif 309 310 #if !__has_extension(c_thread_local) 311 /* 312 * XXX: Some compilers (Clang 3.3, GCC 4.7) falsely announce C++11 mode 313 * without actually supporting the thread_local keyword. Don't check for 314 * the presence of C++11 when defining _Thread_local. 315 */ 316 #if /* (defined(__cplusplus) && __cplusplus >= 201103L) || */ \ 317 __has_extension(cxx_thread_local) 318 #define _Thread_local thread_local 319 #else 320 #define _Thread_local __thread 321 #endif 322 #endif 323 324 #endif /* __STDC_VERSION__ || __STDC_VERSION__ < 201112L */ 325 326 /* 327 * Emulation of C11 _Generic(). Unlike the previously defined C11 328 * keywords, it is not possible to implement this using exactly the same 329 * syntax. Therefore implement something similar under the name 330 * __generic(). Unlike _Generic(), this macro can only distinguish 331 * between a single type, so it requires nested invocations to 332 * distinguish multiple cases. 333 */ 334 335 #if (defined(__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) || \ 336 __has_extension(c_generic_selections) 337 #define __generic(expr, t, yes, no) \ 338 _Generic(expr, t: yes, default: no) 339 #elif __GNUC_PREREQ__(3, 1) && !defined(__cplusplus) 340 #define __generic(expr, t, yes, no) \ 341 __builtin_choose_expr( \ 342 __builtin_types_compatible_p(__typeof(expr), t), yes, no) 343 #endif 344 345 #if __GNUC_PREREQ__(2, 96) 346 #define __malloc_like __attribute__((__malloc__)) 347 #define __pure __attribute__((__pure__)) 348 #else 349 #define __malloc_like 350 #define __pure 351 #endif 352 353 #if __GNUC_PREREQ__(3, 1) || (defined(__INTEL_COMPILER) && __INTEL_COMPILER >= 800) 354 #define __always_inline __attribute__((__always_inline__)) 355 #else 356 #define __always_inline 357 #endif 358 359 #if __GNUC_PREREQ__(3, 1) 360 #define __noinline __attribute__ ((__noinline__)) 361 #else 362 #define __noinline 363 #endif 364 365 #if __GNUC_PREREQ__(3, 3) 366 #define __nonnull(x) __attribute__((__nonnull__(x))) 367 #define __nonnull_all __attribute__((__nonnull__)) 368 #else 369 #define __nonnull(x) 370 #define __nonnull_all 371 #endif 372 373 #if __GNUC_PREREQ__(3, 4) 374 #define __fastcall __attribute__((__fastcall__)) 375 #define __result_use_check __attribute__((__warn_unused_result__)) 376 #else 377 #define __fastcall 378 #define __result_use_check 379 #endif 380 381 #if __GNUC_PREREQ__(4, 1) 382 #define __returns_twice __attribute__((__returns_twice__)) 383 #else 384 #define __returns_twice 385 #endif 386 387 #if __GNUC_PREREQ__(4, 6) || __has_builtin(__builtin_unreachable) 388 #define __unreachable() __builtin_unreachable() 389 #else 390 #define __unreachable() ((void)0) 391 #endif 392 393 /* XXX: should use `#if __STDC_VERSION__ < 199901'. */ 394 #if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER) 395 #define __func__ NULL 396 #endif 397 398 #if (defined(__INTEL_COMPILER) || (defined(__GNUC__) && __GNUC__ >= 2)) && !defined(__STRICT_ANSI__) || __STDC_VERSION__ >= 199901 399 #define __LONG_LONG_SUPPORTED 400 #endif 401 402 /* C++11 exposes a load of C99 stuff */ 403 #if defined(__cplusplus) && __cplusplus >= 201103L 404 #define __LONG_LONG_SUPPORTED 405 #ifndef __STDC_LIMIT_MACROS 406 #define __STDC_LIMIT_MACROS 407 #endif 408 #ifndef __STDC_CONSTANT_MACROS 409 #define __STDC_CONSTANT_MACROS 410 #endif 411 #endif 412 413 /* 414 * GCC 2.95 provides `__restrict' as an extension to C90 to support the 415 * C99-specific `restrict' type qualifier. We happen to use `__restrict' as 416 * a way to define the `restrict' type qualifier without disturbing older 417 * software that is unaware of C99 keywords. 418 */ 419 #if !(__GNUC__ == 2 && __GNUC_MINOR__ == 95) 420 #if !defined(__STDC_VERSION__) || __STDC_VERSION__ < 199901 || defined(lint) 421 #define __restrict 422 #else 423 #define __restrict restrict 424 #endif 425 #endif 426 427 /* 428 * GNU C version 2.96 adds explicit branch prediction so that 429 * the CPU back-end can hint the processor and also so that 430 * code blocks can be reordered such that the predicted path 431 * sees a more linear flow, thus improving cache behavior, etc. 432 * 433 * The following two macros provide us with a way to utilize this 434 * compiler feature. Use __predict_true() if you expect the expression 435 * to evaluate to true, and __predict_false() if you expect the 436 * expression to evaluate to false. 437 * 438 * A few notes about usage: 439 * 440 * * Generally, __predict_false() error condition checks (unless 441 * you have some _strong_ reason to do otherwise, in which case 442 * document it), and/or __predict_true() `no-error' condition 443 * checks, assuming you want to optimize for the no-error case. 444 * 445 * * Other than that, if you don't know the likelihood of a test 446 * succeeding from empirical or other `hard' evidence, don't 447 * make predictions. 448 * 449 * * These are meant to be used in places that are run `a lot'. 450 * It is wasteful to make predictions in code that is run 451 * seldomly (e.g. at subsystem initialization time) as the 452 * basic block reordering that this affects can often generate 453 * larger code. 454 */ 455 #if __GNUC_PREREQ__(2, 96) 456 #define __predict_true(exp) __builtin_expect((exp), 1) 457 #define __predict_false(exp) __builtin_expect((exp), 0) 458 #else 459 #define __predict_true(exp) (exp) 460 #define __predict_false(exp) (exp) 461 #endif 462 463 #if __GNUC_PREREQ__(4, 0) 464 #define __null_sentinel __attribute__((__sentinel__)) 465 #define __exported __attribute__((__visibility__("default"))) 466 #define __hidden __attribute__((__visibility__("hidden"))) 467 #else 468 #define __null_sentinel 469 #define __exported 470 #define __hidden 471 #endif 472 473 /* 474 * We define this here since <stddef.h>, <sys/queue.h>, and <sys/types.h> 475 * require it. 476 */ 477 #if __GNUC_PREREQ__(4, 1) 478 #define __offsetof(type, field) __builtin_offsetof(type, field) 479 #else 480 #ifndef __cplusplus 481 #define __offsetof(type, field) \ 482 ((__size_t)(__uintptr_t)((const volatile void *)&((type *)0)->field)) 483 #else 484 #define __offsetof(type, field) \ 485 (__offsetof__ (reinterpret_cast <__size_t> \ 486 (&reinterpret_cast <const volatile char &> \ 487 (static_cast<type *> (0)->field)))) 488 #endif 489 #endif 490 #define __rangeof(type, start, end) \ 491 (__offsetof(type, end) - __offsetof(type, start)) 492 493 /* 494 * Given the pointer x to the member m of the struct s, return 495 * a pointer to the containing structure. When using GCC, we first 496 * assign pointer x to a local variable, to check that its type is 497 * compatible with member m. 498 */ 499 #if __GNUC_PREREQ__(3, 1) 500 #define __containerof(x, s, m) ({ \ 501 const volatile __typeof(((s *)0)->m) *__x = (x); \ 502 __DEQUALIFY(s *, (const volatile char *)__x - __offsetof(s, m));\ 503 }) 504 #else 505 #define __containerof(x, s, m) \ 506 __DEQUALIFY(s *, (const volatile char *)(x) - __offsetof(s, m)) 507 #endif 508 509 /* 510 * Compiler-dependent macros to declare that functions take printf-like 511 * or scanf-like arguments. They are null except for versions of gcc 512 * that are known to support the features properly (old versions of gcc-2 513 * didn't permit keeping the keywords out of the application namespace). 514 */ 515 #if !__GNUC_PREREQ__(2, 7) && !defined(__INTEL_COMPILER) 516 #define __printflike(fmtarg, firstvararg) 517 #define __scanflike(fmtarg, firstvararg) 518 #define __format_arg(fmtarg) 519 #define __strfmonlike(fmtarg, firstvararg) 520 #define __strftimelike(fmtarg, firstvararg) 521 #else 522 #define __printflike(fmtarg, firstvararg) \ 523 __attribute__((__format__ (__printf__, fmtarg, firstvararg))) 524 #define __scanflike(fmtarg, firstvararg) \ 525 __attribute__((__format__ (__scanf__, fmtarg, firstvararg))) 526 #define __format_arg(fmtarg) __attribute__((__format_arg__ (fmtarg))) 527 #define __strfmonlike(fmtarg, firstvararg) \ 528 __attribute__((__format__ (__strfmon__, fmtarg, firstvararg))) 529 #define __strftimelike(fmtarg, firstvararg) \ 530 __attribute__((__format__ (__strftime__, fmtarg, firstvararg))) 531 #endif 532 533 /* 534 * FORTIFY_SOURCE, and perhaps other compiler-specific features, require 535 * the use of non-standard inlining. In general we should try to avoid 536 * using these but GCC-compatible compilers tend to support the extensions 537 * well enough to use them in limited cases. 538 */ 539 #if defined(__GNUC_GNU_INLINE__) || defined(__GNUC_STDC_INLINE__) 540 #if __GNUC_PREREQ__(4, 3) || __has_attribute(__artificial__) 541 #define __gnu_inline __attribute__((__gnu_inline__, __artificial__)) 542 #else 543 #define __gnu_inline __attribute__((__gnu_inline__)) 544 #endif /* artificial */ 545 #else 546 #define __gnu_inline 547 #endif 548 549 /* Compiler-dependent macros that rely on FreeBSD-specific extensions. */ 550 #if defined(__FreeBSD_cc_version) && __FreeBSD_cc_version >= 300001 && \ 551 defined(__GNUC__) && !defined(__INTEL_COMPILER) 552 #define __printf0like(fmtarg, firstvararg) \ 553 __attribute__((__format__ (__printf0__, fmtarg, firstvararg))) 554 #else 555 #define __printf0like(fmtarg, firstvararg) 556 #endif 557 558 #if defined(__GNUC__) || defined(__INTEL_COMPILER) 559 #ifndef __INTEL_COMPILER 560 #define __strong_reference(sym,aliassym) \ 561 extern __typeof (sym) aliassym __attribute__ ((__alias__ (#sym))) 562 #endif 563 #ifdef __STDC__ 564 #define __weak_reference(sym,alias) \ 565 __asm__(".weak " #alias); \ 566 __asm__(".equ " #alias ", " #sym) 567 #define __warn_references(sym,msg) \ 568 __asm__(".section .gnu.warning." #sym); \ 569 __asm__(".asciz \"" msg "\""); \ 570 __asm__(".previous") 571 #define __sym_compat(sym,impl,verid) \ 572 __asm__(".symver " #impl ", " #sym "@" #verid) 573 #define __sym_default(sym,impl,verid) \ 574 __asm__(".symver " #impl ", " #sym "@@" #verid) 575 #else 576 #define __weak_reference(sym,alias) \ 577 __asm__(".weak alias"); \ 578 __asm__(".equ alias, sym") 579 #define __warn_references(sym,msg) \ 580 __asm__(".section .gnu.warning.sym"); \ 581 __asm__(".asciz \"msg\""); \ 582 __asm__(".previous") 583 #define __sym_compat(sym,impl,verid) \ 584 __asm__(".symver impl, sym@verid") 585 #define __sym_default(impl,sym,verid) \ 586 __asm__(".symver impl, sym@@verid") 587 #endif /* __STDC__ */ 588 #endif /* __GNUC__ || __INTEL_COMPILER */ 589 590 #define __GLOBL(sym) __asm__(".globl " __XSTRING(sym)) 591 #define __WEAK(sym) __asm__(".weak " __XSTRING(sym)) 592 593 #if defined(__GNUC__) || defined(__INTEL_COMPILER) 594 #define __IDSTRING(name,string) __asm__(".ident\t\"" string "\"") 595 #else 596 /* 597 * The following definition might not work well if used in header files, 598 * but it should be better than nothing. If you want a "do nothing" 599 * version, then it should generate some harmless declaration, such as: 600 * #define __IDSTRING(name,string) struct __hack 601 */ 602 #define __IDSTRING(name,string) static const char name[] __unused = string 603 #endif 604 605 /* 606 * Embed the rcs id of a source file in the resulting library. Note that in 607 * more recent ELF binutils, we use .ident allowing the ID to be stripped. 608 * Usage: 609 * __FBSDID("$FreeBSD$"); 610 */ 611 #ifndef __FBSDID 612 #if !defined(lint) && !defined(STRIP_FBSDID) 613 #define __FBSDID(s) __IDSTRING(__CONCAT(__rcsid_,__LINE__),s) 614 #else 615 #define __FBSDID(s) struct __hack 616 #endif 617 #endif 618 619 #ifndef __RCSID 620 #ifndef NO__RCSID 621 #define __RCSID(s) __IDSTRING(__CONCAT(__rcsid_,__LINE__),s) 622 #else 623 #define __RCSID(s) struct __hack 624 #endif 625 #endif 626 627 #ifndef __RCSID_SOURCE 628 #ifndef NO__RCSID_SOURCE 629 #define __RCSID_SOURCE(s) __IDSTRING(__CONCAT(__rcsid_source_,__LINE__),s) 630 #else 631 #define __RCSID_SOURCE(s) struct __hack 632 #endif 633 #endif 634 635 #ifndef __SCCSID 636 #ifndef NO__SCCSID 637 #define __SCCSID(s) __IDSTRING(__CONCAT(__sccsid_,__LINE__),s) 638 #else 639 #define __SCCSID(s) struct __hack 640 #endif 641 #endif 642 643 #ifndef __COPYRIGHT 644 #ifndef NO__COPYRIGHT 645 #define __COPYRIGHT(s) __IDSTRING(__CONCAT(__copyright_,__LINE__),s) 646 #else 647 #define __COPYRIGHT(s) struct __hack 648 #endif 649 #endif 650 651 #ifndef __DECONST 652 #define __DECONST(type, var) ((type)(__uintptr_t)(const void *)(var)) 653 #endif 654 655 #ifndef __DEVOLATILE 656 #define __DEVOLATILE(type, var) ((type)(__uintptr_t)(volatile void *)(var)) 657 #endif 658 659 #ifndef __DEQUALIFY 660 #define __DEQUALIFY(type, var) ((type)(__uintptr_t)(const volatile void *)(var)) 661 #endif 662 663 /*- 664 * The following definitions are an extension of the behavior originally 665 * implemented in <sys/_posix.h>, but with a different level of granularity. 666 * POSIX.1 requires that the macros we test be defined before any standard 667 * header file is included. 668 * 669 * Here's a quick run-down of the versions: 670 * defined(_POSIX_SOURCE) 1003.1-1988 671 * _POSIX_C_SOURCE == 1 1003.1-1990 672 * _POSIX_C_SOURCE == 2 1003.2-1992 C Language Binding Option 673 * _POSIX_C_SOURCE == 199309 1003.1b-1993 674 * _POSIX_C_SOURCE == 199506 1003.1c-1995, 1003.1i-1995, 675 * and the omnibus ISO/IEC 9945-1: 1996 676 * _POSIX_C_SOURCE == 200112 1003.1-2001 677 * _POSIX_C_SOURCE == 200809 1003.1-2008 678 * 679 * In addition, the X/Open Portability Guide, which is now the Single UNIX 680 * Specification, defines a feature-test macro which indicates the version of 681 * that specification, and which subsumes _POSIX_C_SOURCE. 682 * 683 * Our macros begin with two underscores to avoid namespace screwage. 684 */ 685 686 /* Deal with IEEE Std. 1003.1-1990, in which _POSIX_C_SOURCE == 1. */ 687 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 1 688 #undef _POSIX_C_SOURCE /* Probably illegal, but beyond caring now. */ 689 #define _POSIX_C_SOURCE 199009 690 #endif 691 692 /* Deal with IEEE Std. 1003.2-1992, in which _POSIX_C_SOURCE == 2. */ 693 #if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE == 2 694 #undef _POSIX_C_SOURCE 695 #define _POSIX_C_SOURCE 199209 696 #endif 697 698 /* Deal with various X/Open Portability Guides and Single UNIX Spec. */ 699 #ifdef _XOPEN_SOURCE 700 #if _XOPEN_SOURCE - 0 >= 700 701 #define __XSI_VISIBLE 700 702 #undef _POSIX_C_SOURCE 703 #define _POSIX_C_SOURCE 200809 704 #elif _XOPEN_SOURCE - 0 >= 600 705 #define __XSI_VISIBLE 600 706 #undef _POSIX_C_SOURCE 707 #define _POSIX_C_SOURCE 200112 708 #elif _XOPEN_SOURCE - 0 >= 500 709 #define __XSI_VISIBLE 500 710 #undef _POSIX_C_SOURCE 711 #define _POSIX_C_SOURCE 199506 712 #endif 713 #endif 714 715 /* 716 * Deal with all versions of POSIX. The ordering relative to the tests above is 717 * important. 718 */ 719 #if defined(_POSIX_SOURCE) && !defined(_POSIX_C_SOURCE) 720 #define _POSIX_C_SOURCE 198808 721 #endif 722 #ifdef _POSIX_C_SOURCE 723 #if _POSIX_C_SOURCE >= 200809 724 #define __POSIX_VISIBLE 200809 725 #define __ISO_C_VISIBLE 1999 726 #elif _POSIX_C_SOURCE >= 200112 727 #define __POSIX_VISIBLE 200112 728 #define __ISO_C_VISIBLE 1999 729 #elif _POSIX_C_SOURCE >= 199506 730 #define __POSIX_VISIBLE 199506 731 #define __ISO_C_VISIBLE 1990 732 #elif _POSIX_C_SOURCE >= 199309 733 #define __POSIX_VISIBLE 199309 734 #define __ISO_C_VISIBLE 1990 735 #elif _POSIX_C_SOURCE >= 199209 736 #define __POSIX_VISIBLE 199209 737 #define __ISO_C_VISIBLE 1990 738 #elif _POSIX_C_SOURCE >= 199009 739 #define __POSIX_VISIBLE 199009 740 #define __ISO_C_VISIBLE 1990 741 #else 742 #define __POSIX_VISIBLE 198808 743 #define __ISO_C_VISIBLE 0 744 #endif /* _POSIX_C_SOURCE */ 745 #else 746 /*- 747 * Deal with _ANSI_SOURCE: 748 * If it is defined, and no other compilation environment is explicitly 749 * requested, then define our internal feature-test macros to zero. This 750 * makes no difference to the preprocessor (undefined symbols in preprocessing 751 * expressions are defined to have value zero), but makes it more convenient for 752 * a test program to print out the values. 753 * 754 * If a program mistakenly defines _ANSI_SOURCE and some other macro such as 755 * _POSIX_C_SOURCE, we will assume that it wants the broader compilation 756 * environment (and in fact we will never get here). 757 */ 758 #if defined(_ANSI_SOURCE) /* Hide almost everything. */ 759 #define __POSIX_VISIBLE 0 760 #define __XSI_VISIBLE 0 761 #define __BSD_VISIBLE 0 762 #define __ISO_C_VISIBLE 1990 763 #elif defined(_C99_SOURCE) /* Localism to specify strict C99 env. */ 764 #define __POSIX_VISIBLE 0 765 #define __XSI_VISIBLE 0 766 #define __BSD_VISIBLE 0 767 #define __ISO_C_VISIBLE 1999 768 #elif defined(_C11_SOURCE) /* Localism to specify strict C11 env. */ 769 #define __POSIX_VISIBLE 0 770 #define __XSI_VISIBLE 0 771 #define __BSD_VISIBLE 0 772 #define __ISO_C_VISIBLE 2011 773 #else /* Default environment: show everything. */ 774 #define __POSIX_VISIBLE 200809 775 #define __XSI_VISIBLE 700 776 #define __BSD_VISIBLE 1 777 #define __ISO_C_VISIBLE 2011 778 #endif 779 #endif 780 781 #if defined(__mips) || defined(__powerpc64__) || defined(__riscv__) 782 #define __NO_TLS 1 783 #endif 784 785 /* 786 * Type Safety Checking 787 * 788 * Clang provides additional attributes to enable checking type safety 789 * properties that cannot be enforced by the C type system. 790 */ 791 792 #if __has_attribute(__argument_with_type_tag__) && \ 793 __has_attribute(__type_tag_for_datatype__) && !defined(lint) 794 #define __arg_type_tag(arg_kind, arg_idx, type_tag_idx) \ 795 __attribute__((__argument_with_type_tag__(arg_kind, arg_idx, type_tag_idx))) 796 #define __datatype_type_tag(kind, type) \ 797 __attribute__((__type_tag_for_datatype__(kind, type))) 798 #else 799 #define __arg_type_tag(arg_kind, arg_idx, type_tag_idx) 800 #define __datatype_type_tag(kind, type) 801 #endif 802 803 /* 804 * Lock annotations. 805 * 806 * Clang provides support for doing basic thread-safety tests at 807 * compile-time, by marking which locks will/should be held when 808 * entering/leaving a functions. 809 * 810 * Furthermore, it is also possible to annotate variables and structure 811 * members to enforce that they are only accessed when certain locks are 812 * held. 813 */ 814 815 #if __has_extension(c_thread_safety_attributes) 816 #define __lock_annotate(x) __attribute__((x)) 817 #else 818 #define __lock_annotate(x) 819 #endif 820 821 /* Structure implements a lock. */ 822 #define __lockable __lock_annotate(lockable) 823 824 /* Function acquires an exclusive or shared lock. */ 825 #define __locks_exclusive(...) \ 826 __lock_annotate(exclusive_lock_function(__VA_ARGS__)) 827 #define __locks_shared(...) \ 828 __lock_annotate(shared_lock_function(__VA_ARGS__)) 829 830 /* Function attempts to acquire an exclusive or shared lock. */ 831 #define __trylocks_exclusive(...) \ 832 __lock_annotate(exclusive_trylock_function(__VA_ARGS__)) 833 #define __trylocks_shared(...) \ 834 __lock_annotate(shared_trylock_function(__VA_ARGS__)) 835 836 /* Function releases a lock. */ 837 #define __unlocks(...) __lock_annotate(unlock_function(__VA_ARGS__)) 838 839 /* Function asserts that an exclusive or shared lock is held. */ 840 #define __asserts_exclusive(...) \ 841 __lock_annotate(assert_exclusive_lock(__VA_ARGS__)) 842 #define __asserts_shared(...) \ 843 __lock_annotate(assert_shared_lock(__VA_ARGS__)) 844 845 /* Function requires that an exclusive or shared lock is or is not held. */ 846 #define __requires_exclusive(...) \ 847 __lock_annotate(exclusive_locks_required(__VA_ARGS__)) 848 #define __requires_shared(...) \ 849 __lock_annotate(shared_locks_required(__VA_ARGS__)) 850 #define __requires_unlocked(...) \ 851 __lock_annotate(locks_excluded(__VA_ARGS__)) 852 853 /* Function should not be analyzed. */ 854 #define __no_lock_analysis __lock_annotate(no_thread_safety_analysis) 855 856 /* Guard variables and structure members by lock. */ 857 #define __guarded_by(x) __lock_annotate(guarded_by(x)) 858 #define __pt_guarded_by(x) __lock_annotate(pt_guarded_by(x)) 859 860 #endif /* !_SYS_CDEFS_H_ */ 861