gcc/ginclude/stddef.h

   1 /* Copyright (C) 1989-2024 Free Software Foundation, Inc.
   2
   3 This file is part of GCC.
   4
   5 GCC is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation; either version 3, or (at your option)
   8 any later version.
   9
  10 GCC 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
  13 GNU General Public License for more details.
  14
  15 Under Section 7 of GPL version 3, you are granted additional
  16 permissions described in the GCC Runtime Library Exception, version
  17 3.1, as published by the Free Software Foundation.
  18
  19 You should have received a copy of the GNU General Public License and
  20 a copy of the GCC Runtime Library Exception along with this program;
  21 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  22 <http://www.gnu.org/licenses/>.  */
  23
  24 /*
  25  * ISO C Standard:  7.17  Common definitions  <stddef.h>
  26  */
  27 #if (!defined(_STDDEF_H) && !defined(_STDDEF_H_) && !defined(_ANSI_STDDEF_H) \
  28      && !defined(__STDDEF_H__)) \
  29     || defined(__need_wchar_t) || defined(__need_size_t) \
  30     || defined(__need_ptrdiff_t) || defined(__need_NULL) \
  31     || defined(__need_wint_t)
  32
  33 /* Any one of these symbols __need_* means that GNU libc
  34    wants us just to define one data type.  So don't define
  35    the symbols that indicate this file's entire job has been done.  */
  36 #if (!defined(__need_wchar_t) && !defined(__need_size_t)        \
  37      && !defined(__need_ptrdiff_t) && !defined(__need_NULL)     \
  38      && !defined(__need_wint_t))
  39 #define _STDDEF_H
  40 #define _STDDEF_H_
  41 /* snaroff@next.com says the NeXT needs this.  */
  42 #define _ANSI_STDDEF_H
  43 #endif
  44
  45 #ifndef __sys_stdtypes_h
  46 /* This avoids lossage on SunOS but only if stdtypes.h comes first.
  47    There's no way to win with the other order!  Sun lossage.  */
  48
  49 #if defined(__NetBSD__)
  50 #include <machine/ansi.h>
  51 #endif
  52
  53 #if defined (__FreeBSD__)
  54 #include <sys/_types.h>
  55 #endif
  56
  57 #if defined(__NetBSD__)
  58 #if !defined(_SIZE_T_) && !defined(_BSD_SIZE_T_)
  59 #define _SIZE_T
  60 #endif
  61 #if !defined(_PTRDIFF_T_) && !defined(_BSD_PTRDIFF_T_)
  62 #define _PTRDIFF_T
  63 #endif
  64 /* On BSD/386 1.1, at least, machine/ansi.h defines _BSD_WCHAR_T_
  65    instead of _WCHAR_T_. */
  66 #if !defined(_WCHAR_T_) && !defined(_BSD_WCHAR_T_)
  67 #ifndef _BSD_WCHAR_T_
  68 #define _WCHAR_T
  69 #endif
  70 #endif
  71 /* Undef _FOO_T_ if we are supposed to define foo_t.  */
  72 #if defined (__need_ptrdiff_t) || defined (_STDDEF_H_)
  73 #undef _PTRDIFF_T_
  74 #undef _BSD_PTRDIFF_T_
  75 #endif
  76 #if defined (__need_size_t) || defined (_STDDEF_H_)
  77 #undef _SIZE_T_
  78 #undef _BSD_SIZE_T_
  79 #endif
  80 #if defined (__need_wchar_t) || defined (_STDDEF_H_)
  81 #undef _WCHAR_T_
  82 #undef _BSD_WCHAR_T_
  83 #endif
  84 #endif /* defined(__NetBSD__) */
  85
  86 /* Sequent's header files use _PTRDIFF_T_ in some conflicting way.
  87    Just ignore it.  */
  88 #if defined (__sequent__) && defined (_PTRDIFF_T_)
  89 #undef _PTRDIFF_T_
  90 #endif
  91
  92 /* On VxWorks, <type/vxTypesBase.h> may have defined macros like
  93    _TYPE_size_t which will typedef size_t.  fixincludes patched the
  94    vxTypesBase.h so that this macro is only defined if _GCC_SIZE_T is
  95    not defined, and so that defining this macro defines _GCC_SIZE_T.
  96    If we find that the macros are still defined at this point, we must
  97    invoke them so that the type is defined as expected.  */
  98 #if defined (_TYPE_ptrdiff_t) && (defined (__need_ptrdiff_t) || defined (_STDDEF_H_))
  99 _TYPE_ptrdiff_t;
 100 #undef _TYPE_ptrdiff_t
 101 #endif
 102 #if defined (_TYPE_size_t) && (defined (__need_size_t) || defined (_STDDEF_H_))
 103 _TYPE_size_t;
 104 #undef _TYPE_size_t
 105 #endif
 106 #if defined (_TYPE_wchar_t) && (defined (__need_wchar_t) || defined (_STDDEF_H_))
 107 _TYPE_wchar_t;
 108 #undef _TYPE_wchar_t
 109 #endif
 110
 111 /* In case nobody has defined these types, but we aren't running under
 112    GCC 2.00, make sure that __PTRDIFF_TYPE__, __SIZE_TYPE__, and
 113    __WCHAR_TYPE__ have reasonable values.  This can happen if the
 114    parts of GCC is compiled by an older compiler, that actually
 115    include gstddef.h, such as collect2.  */
 116
 117 /* Signed type of difference of two pointers.  */
 118
 119 /* Define this type if we are doing the whole job,
 120    or if we want this type in particular.  */
 121 #if defined (_STDDEF_H) || defined (__need_ptrdiff_t)
 122 #ifndef _PTRDIFF_T      /* in case <sys/types.h> has defined it. */
 123 #ifndef _T_PTRDIFF_
 124 #ifndef _T_PTRDIFF
 125 #ifndef __PTRDIFF_T
 126 #ifndef _PTRDIFF_T_
 127 #ifndef _BSD_PTRDIFF_T_
 128 #ifndef ___int_ptrdiff_t_h
 129 #ifndef _GCC_PTRDIFF_T
 130 #ifndef _PTRDIFF_T_DECLARED /* DragonFly */
 131 #ifndef __DEFINED_ptrdiff_t /* musl libc */
 132 #define _PTRDIFF_T
 133 #define _T_PTRDIFF_
 134 #define _T_PTRDIFF
 135 #define __PTRDIFF_T
 136 #define _PTRDIFF_T_
 137 #define _BSD_PTRDIFF_T_
 138 #define ___int_ptrdiff_t_h
 139 #define _GCC_PTRDIFF_T
 140 #define _PTRDIFF_T_DECLARED
 141 #define __DEFINED_ptrdiff_t
 142 #ifndef __PTRDIFF_TYPE__
 143 #define __PTRDIFF_TYPE__ long int
 144 #endif
 145 typedef __PTRDIFF_TYPE__ ptrdiff_t;
 146 #endif /* __DEFINED_ptrdiff_t */
 147 #endif /* _PTRDIFF_T_DECLARED */
 148 #endif /* _GCC_PTRDIFF_T */
 149 #endif /* ___int_ptrdiff_t_h */
 150 #endif /* _BSD_PTRDIFF_T_ */
 151 #endif /* _PTRDIFF_T_ */
 152 #endif /* __PTRDIFF_T */
 153 #endif /* _T_PTRDIFF */
 154 #endif /* _T_PTRDIFF_ */
 155 #endif /* _PTRDIFF_T */
 156
 157 /* If this symbol has done its job, get rid of it.  */
 158 #undef  __need_ptrdiff_t
 159
 160 #endif /* _STDDEF_H or __need_ptrdiff_t.  */
 161
 162 /* Unsigned type of `sizeof' something.  */
 163
 164 /* Define this type if we are doing the whole job,
 165    or if we want this type in particular.  */
 166 #if defined (_STDDEF_H) || defined (__need_size_t)
 167 #ifndef __size_t__      /* BeOS */
 168 #ifndef __SIZE_T__      /* Cray Unicos/Mk */
 169 #ifndef _SIZE_T /* in case <sys/types.h> has defined it. */
 170 #ifndef _SYS_SIZE_T_H
 171 #ifndef _T_SIZE_
 172 #ifndef _T_SIZE
 173 #ifndef __SIZE_T
 174 #ifndef _SIZE_T_
 175 #ifndef _BSD_SIZE_T_
 176 #ifndef _SIZE_T_DEFINED_
 177 #ifndef _SIZE_T_DEFINED
 178 #ifndef _BSD_SIZE_T_DEFINED_    /* Darwin */
 179 #ifndef _SIZE_T_DECLARED        /* FreeBSD 5 */
 180 #ifndef __DEFINED_size_t        /* musl libc */
 181 #ifndef ___int_size_t_h
 182 #ifndef _GCC_SIZE_T
 183 #ifndef _SIZET_
 184 #ifndef __size_t
 185 #define __size_t__      /* BeOS */
 186 #define __SIZE_T__      /* Cray Unicos/Mk */
 187 #define _SIZE_T
 188 #define _SYS_SIZE_T_H
 189 #define _T_SIZE_
 190 #define _T_SIZE
 191 #define __SIZE_T
 192 #define _SIZE_T_
 193 #define _BSD_SIZE_T_
 194 #define _SIZE_T_DEFINED_
 195 #define _SIZE_T_DEFINED
 196 #define _BSD_SIZE_T_DEFINED_    /* Darwin */
 197 #define _SIZE_T_DECLARED        /* FreeBSD 5 */
 198 #define __DEFINED_size_t        /* musl libc */
 199 #define ___int_size_t_h
 200 #define _GCC_SIZE_T
 201 #define _SIZET_
 202 #if defined (__FreeBSD__) \
 203   || defined(__DragonFly__) \
 204   || defined(__FreeBSD_kernel__) \
 205   || defined(__VMS__)
 206 /* __size_t is a typedef, must not trash it.  */
 207 #else
 208 #define __size_t
 209 #endif
 210 #ifndef __SIZE_TYPE__
 211 #define __SIZE_TYPE__ long unsigned int
 212 #endif
 213 #if !(defined (__GNUG__) && defined (size_t))
 214 typedef __SIZE_TYPE__ size_t;
 215 #ifdef __BEOS__
 216 typedef long ssize_t;
 217 #endif /* __BEOS__ */
 218 #endif /* !(defined (__GNUG__) && defined (size_t)) */
 219 #endif /* __size_t */
 220 #endif /* _SIZET_ */
 221 #endif /* _GCC_SIZE_T */
 222 #endif /* ___int_size_t_h */
 223 #endif /* __DEFINED_size_t */
 224 #endif /* _SIZE_T_DECLARED */
 225 #endif /* _BSD_SIZE_T_DEFINED_ */
 226 #endif /* _SIZE_T_DEFINED */
 227 #endif /* _SIZE_T_DEFINED_ */
 228 #endif /* _BSD_SIZE_T_ */
 229 #endif /* _SIZE_T_ */
 230 #endif /* __SIZE_T */
 231 #endif /* _T_SIZE */
 232 #endif /* _T_SIZE_ */
 233 #endif /* _SYS_SIZE_T_H */
 234 #endif /* _SIZE_T */
 235 #endif /* __SIZE_T__ */
 236 #endif /* __size_t__ */
 237 #undef  __need_size_t
 238 #endif /* _STDDEF_H or __need_size_t.  */
 239
 240
 241 /* Wide character type.
 242    Locale-writers should change this as necessary to
 243    be big enough to hold unique values not between 0 and 127,
 244    and not (wchar_t) -1, for each defined multibyte character.  */
 245
 246 /* Define this type if we are doing the whole job,
 247    or if we want this type in particular.  */
 248 #if defined (_STDDEF_H) || defined (__need_wchar_t)
 249 #ifndef __wchar_t__     /* BeOS */
 250 #ifndef __WCHAR_T__     /* Cray Unicos/Mk */
 251 #ifndef _WCHAR_T
 252 #ifndef _T_WCHAR_
 253 #ifndef _T_WCHAR
 254 #ifndef __WCHAR_T
 255 #ifndef _WCHAR_T_
 256 #ifndef _BSD_WCHAR_T_
 257 #ifndef _BSD_WCHAR_T_DEFINED_    /* Darwin */
 258 #ifndef _BSD_RUNE_T_DEFINED_    /* Darwin */
 259 #ifndef _WCHAR_T_DECLARED /* FreeBSD 5 */
 260 #ifndef __DEFINED_wchar_t /* musl libc */
 261 #ifndef _WCHAR_T_DEFINED_
 262 #ifndef _WCHAR_T_DEFINED
 263 #ifndef _WCHAR_T_H
 264 #ifndef ___int_wchar_t_h
 265 #ifndef __INT_WCHAR_T_H
 266 #ifndef _GCC_WCHAR_T
 267 #define __wchar_t__     /* BeOS */
 268 #define __WCHAR_T__     /* Cray Unicos/Mk */
 269 #define _WCHAR_T
 270 #define _T_WCHAR_
 271 #define _T_WCHAR
 272 #define __WCHAR_T
 273 #define _WCHAR_T_
 274 #define _BSD_WCHAR_T_
 275 #define _WCHAR_T_DEFINED_
 276 #define _WCHAR_T_DEFINED
 277 #define _WCHAR_T_H
 278 #define ___int_wchar_t_h
 279 #define __INT_WCHAR_T_H
 280 #define _GCC_WCHAR_T
 281 #define _WCHAR_T_DECLARED
 282 #define __DEFINED_wchar_t
 283
 284 /* On BSD/386 1.1, at least, machine/ansi.h defines _BSD_WCHAR_T_
 285    instead of _WCHAR_T_, and _BSD_RUNE_T_ (which, unlike the other
 286    symbols in the _FOO_T_ family, stays defined even after its
 287    corresponding type is defined).  If we define wchar_t, then we
 288    must undef _WCHAR_T_; for BSD/386 1.1 (and perhaps others), if
 289    we undef _WCHAR_T_, then we must also define rune_t, since
 290    headers like runetype.h assume that if machine/ansi.h is included,
 291    and _BSD_WCHAR_T_ is not defined, then rune_t is available.
 292    machine/ansi.h says, "Note that _WCHAR_T_ and _RUNE_T_ must be of
 293    the same type." */
 294 #ifdef _BSD_WCHAR_T_
 295 #undef _BSD_WCHAR_T_
 296 #ifdef _BSD_RUNE_T_
 297 #if !defined (_ANSI_SOURCE) && !defined (_POSIX_SOURCE)
 298 typedef _BSD_RUNE_T_ rune_t;
 299 #define _BSD_WCHAR_T_DEFINED_
 300 #define _BSD_RUNE_T_DEFINED_    /* Darwin */
 301 #if defined (__FreeBSD__) && (__FreeBSD__ < 5)
 302 /* Why is this file so hard to maintain properly?  In contrast to
 303    the comment above regarding BSD/386 1.1, on FreeBSD for as long
 304    as the symbol has existed, _BSD_RUNE_T_ must not stay defined or
 305    redundant typedefs will occur when stdlib.h is included after this file. */
 306 #undef _BSD_RUNE_T_
 307 #endif
 308 #endif
 309 #endif
 310 #endif
 311 /* FreeBSD 5 can't be handled well using "traditional" logic above
 312    since it no longer defines _BSD_RUNE_T_ yet still desires to export
 313    rune_t in some cases... */
 314 #if defined (__FreeBSD__) && (__FreeBSD__ >= 5)
 315 #if !defined (_ANSI_SOURCE) && !defined (_POSIX_SOURCE)
 316 #if __BSD_VISIBLE
 317 #ifndef _RUNE_T_DECLARED
 318 typedef __rune_t        rune_t;
 319 #define _RUNE_T_DECLARED
 320 #endif
 321 #endif
 322 #endif
 323 #endif
 324
 325 #ifndef __WCHAR_TYPE__
 326 #define __WCHAR_TYPE__ int
 327 #endif
 328 #ifndef __cplusplus
 329 typedef __WCHAR_TYPE__ wchar_t;
 330 #endif
 331 #endif
 332 #endif
 333 #endif
 334 #endif
 335 #endif
 336 #endif
 337 #endif /* __DEFINED_wchar_t */
 338 #endif /* _WCHAR_T_DECLARED */
 339 #endif /* _BSD_RUNE_T_DEFINED_ */
 340 #endif
 341 #endif
 342 #endif
 343 #endif
 344 #endif
 345 #endif
 346 #endif
 347 #endif /* __WCHAR_T__ */
 348 #endif /* __wchar_t__ */
 349 #undef  __need_wchar_t
 350 #endif /* _STDDEF_H or __need_wchar_t.  */
 351
 352 #if defined (__need_wint_t)
 353 #ifndef _WINT_T
 354 #define _WINT_T
 355
 356 #ifndef __WINT_TYPE__
 357 #define __WINT_TYPE__ unsigned int
 358 #endif
 359 typedef __WINT_TYPE__ wint_t;
 360 #endif
 361 #undef __need_wint_t
 362 #endif
 363
 364 #if defined(__NetBSD__)
 365 /*  The references to _GCC_PTRDIFF_T_, _GCC_SIZE_T_, and _GCC_WCHAR_T_
 366     are probably typos and should be removed before 2.8 is released.  */
 367 #ifdef _GCC_PTRDIFF_T_
 368 #undef _PTRDIFF_T_
 369 #undef _BSD_PTRDIFF_T_
 370 #endif
 371 #ifdef _GCC_SIZE_T_
 372 #undef _SIZE_T_
 373 #undef _BSD_SIZE_T_
 374 #endif
 375 #ifdef _GCC_WCHAR_T_
 376 #undef _WCHAR_T_
 377 #undef _BSD_WCHAR_T_
 378 #endif
 379 /*  The following ones are the real ones.  */
 380 #ifdef _GCC_PTRDIFF_T
 381 #undef _PTRDIFF_T_
 382 #undef _BSD_PTRDIFF_T_
 383 #endif
 384 #ifdef _GCC_SIZE_T
 385 #undef _SIZE_T_
 386 #undef _BSD_SIZE_T_
 387 #endif
 388 #ifdef _GCC_WCHAR_T
 389 #undef _WCHAR_T_
 390 #undef _BSD_WCHAR_T_
 391 #endif
 392 #endif /* __NetBSD__ */
 393
 394 #endif /* __sys_stdtypes_h */
 395
 396 /* A null pointer constant.  */
 397
 398 #if defined (_STDDEF_H) || defined (__need_NULL)
 399 #undef NULL             /* in case <stdio.h> has defined it. */
 400 #ifdef __GNUG__
 401 #define NULL __null
 402 #else   /* G++ */
 403 #ifndef __cplusplus
 404 #define NULL ((void *)0)
 405 #else   /* C++ */
 406 #define NULL 0
 407 #endif  /* C++ */
 408 #endif  /* G++ */
 409 #endif  /* NULL not defined and <stddef.h> or need NULL.  */
 410 #undef  __need_NULL
 411
 412 #ifdef _STDDEF_H
 413
 414 /* Offset of member MEMBER in a struct of type TYPE. */
 415 #undef offsetof         /* in case a system header has defined it. */
 416 #define offsetof(TYPE, MEMBER) __builtin_offsetof (TYPE, MEMBER)
 417
 418 #if (defined (__STDC_VERSION__) && __STDC_VERSION__ >= 201112L) \
 419   || (defined(__cplusplus) && __cplusplus >= 201103L)
 420 #ifndef _GCC_MAX_ALIGN_T
 421 #define _GCC_MAX_ALIGN_T
 422 /* Type whose alignment is supported in every context and is at least
 423    as great as that of any standard type not using alignment
 424    specifiers.  */
 425 typedef struct {
 426   long long __max_align_ll __attribute__((__aligned__(__alignof__(long long))));
 427   long double __max_align_ld __attribute__((__aligned__(__alignof__(long double))));
 428   /* _Float128 is defined as a basic type, so max_align_t must be
 429      sufficiently aligned for it.  This code must work in C++, so we
 430      use __float128 here; that is only available on some
 431      architectures, but only on i386 is extra alignment needed for
 432      __float128.  */
 433 #ifdef __i386__
 434   __float128 __max_align_f128 __attribute__((__aligned__(__alignof(__float128))));
 435 #endif
 436 } max_align_t;
 437 #endif
 438 #endif /* C11 or C++11.  */
 439
 440 #if defined(__cplusplus) && __cplusplus >= 201103L
 441 #ifndef _GXX_NULLPTR_T
 442 #define _GXX_NULLPTR_T
 443   typedef decltype(nullptr) nullptr_t;
 444 #endif
 445 #endif /* C++11.  */
 446
 447 #if (defined (__STDC_VERSION__) && __STDC_VERSION__ > 201710L)
 448 #ifndef _GCC_NULLPTR_T
 449 #define _GCC_NULLPTR_T
 450   typedef __typeof__(nullptr) nullptr_t;
 451 /* ??? This doesn't define __STDC_VERSION_STDDEF_H__ yet.  */
 452 #endif
 453 #endif /* C23.  */
 454
 455 #if defined __STDC_VERSION__ && __STDC_VERSION__ > 201710L
 456 #define unreachable() (__builtin_unreachable ())
 457 #define __STDC_VERSION_STDDEF_H__       202311L
 458 #endif
 459
 460 #endif /* _STDDEF_H was defined this time */
 461
 462 #endif /* !_STDDEF_H && !_STDDEF_H_ && !_ANSI_STDDEF_H && !__STDDEF_H__
 463           || __need_XXX was not defined before */