misc/sys/cdefs.h

   1 /* Copyright (C) 1992-2002, 2004, 2005, 2006, 2007, 2009, 2011, 2012
   2    Free Software Foundation, Inc.
   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    <http://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    anymore supported.  */
  30 #if defined __GNUC__ && !defined __STDC__
  31 # error "You need a ISO 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 #ifdef __GNUC__
  39
  40 /* All functions, except those with callbacks or those that
  41    synchronize memory, are leaf functions.  */
  42 # if __GNUC_PREREQ (4, 6) && !defined _LIBC
  43 #  define __LEAF , __leaf__
  44 #  define __LEAF_ATTR __attribute__ ((__leaf__))
  45 # else
  46 #  define __LEAF
  47 #  define __LEAF_ATTR
  48 # endif
  49
  50 /* GCC can always grok prototypes.  For C++ programs we add throw()
  51    to help it optimize the function calls.  But this works only with
  52    gcc 2.8.x and egcs.  For gcc 3.2 and up we even mark C functions
  53    as non-throwing using a function attribute since programs can use
  54    the -fexceptions options for C code as well.  */
  55 # if !defined __cplusplus && __GNUC_PREREQ (3, 3)
  56 #  define __THROW       __attribute__ ((__nothrow__ __LEAF))
  57 #  define __THROWNL     __attribute__ ((__nothrow__))
  58 #  define __NTH(fct)    __attribute__ ((__nothrow__ __LEAF)) 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 #  else
  65 #   define __THROW
  66 #   define __THROWNL
  67 #   define __NTH(fct)   fct
  68 #  endif
  69 # endif
  70
  71 #else   /* Not GCC.  */
  72
  73 # define __inline               /* No inline functions.  */
  74
  75 # define __THROW
  76 # define __THROWNL
  77 # define __NTH(fct)     fct
  78
  79 #endif  /* GCC.  */
  80
  81 /* These two macros are not used in glibc anymore.  They are kept here
  82    only because some other projects expect the macros to be defined.  */
  83 #define __P(args)       args
  84 #define __PMT(args)     args
  85
  86 /* For these things, GCC behaves the ANSI way normally,
  87    and the non-ANSI way under -traditional.  */
  88
  89 #define __CONCAT(x,y)   x ## y
  90 #define __STRING(x)     #x
  91
  92 /* This is not a typedef so `const __ptr_t' does the right thing.  */
  93 #define __ptr_t void *
  94 #define __long_double_t  long double
  95
  96
  97 /* C++ needs to know that types and declarations are C, not C++.  */
  98 #ifdef  __cplusplus
  99 # define __BEGIN_DECLS  extern "C" {
 100 # define __END_DECLS    }
 101 #else
 102 # define __BEGIN_DECLS
 103 # define __END_DECLS
 104 #endif
 105
 106
 107 /* The standard library needs the functions from the ISO C90 standard
 108    in the std namespace.  At the same time we want to be safe for
 109    future changes and we include the ISO C99 code in the non-standard
 110    namespace __c99.  The C++ wrapper header take case of adding the
 111    definitions to the global namespace.  */
 112 #if defined __cplusplus && defined _GLIBCPP_USE_NAMESPACES
 113 # define __BEGIN_NAMESPACE_STD  namespace std {
 114 # define __END_NAMESPACE_STD    }
 115 # define __USING_NAMESPACE_STD(name) using std::name;
 116 # define __BEGIN_NAMESPACE_C99  namespace __c99 {
 117 # define __END_NAMESPACE_C99    }
 118 # define __USING_NAMESPACE_C99(name) using __c99::name;
 119 #else
 120 /* For compatibility we do not add the declarations into any
 121    namespace.  They will end up in the global namespace which is what
 122    old code expects.  */
 123 # define __BEGIN_NAMESPACE_STD
 124 # define __END_NAMESPACE_STD
 125 # define __USING_NAMESPACE_STD(name)
 126 # define __BEGIN_NAMESPACE_C99
 127 # define __END_NAMESPACE_C99
 128 # define __USING_NAMESPACE_C99(name)
 129 #endif
 130
 131
 132 /* Support for bounded pointers.  */
 133 #ifndef __BOUNDED_POINTERS__
 134 # define __bounded      /* nothing */
 135 # define __unbounded    /* nothing */
 136 # define __ptrvalue     /* nothing */
 137 #endif
 138
 139
 140 /* Fortify support.  */
 141 #define __bos(ptr) __builtin_object_size (ptr, __USE_FORTIFY_LEVEL > 1)
 142 #define __bos0(ptr) __builtin_object_size (ptr, 0)
 143 #define __fortify_function __extern_always_inline __attribute_artificial__
 144
 145 #if __GNUC_PREREQ (4,3)
 146 # define __warndecl(name, msg) \
 147   extern void name (void) __attribute__((__warning__ (msg)))
 148 # define __warnattr(msg) __attribute__((__warning__ (msg)))
 149 # define __errordecl(name, msg) \
 150   extern void name (void) __attribute__((__error__ (msg)))
 151 #else
 152 # define __warndecl(name, msg) extern void name (void)
 153 # define __warnattr(msg)
 154 # define __errordecl(name, msg) extern void name (void)
 155 #endif
 156
 157 /* Support for flexible arrays.  */
 158 #if __GNUC_PREREQ (2,97)
 159 /* GCC 2.97 supports C99 flexible array members.  */
 160 # define __flexarr      []
 161 #else
 162 # ifdef __GNUC__
 163 #  define __flexarr     [0]
 164 # else
 165 #  if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
 166 #   define __flexarr    []
 167 #  else
 168 /* Some other non-C99 compiler.  Approximate with [1].  */
 169 #   define __flexarr    [1]
 170 #  endif
 171 # endif
 172 #endif
 173
 174
 175 /* __asm__ ("xyz") is used throughout the headers to rename functions
 176    at the assembly language level.  This is wrapped by the __REDIRECT
 177    macro, in order to support compilers that can do this some other
 178    way.  When compilers don't support asm-names at all, we have to do
 179    preprocessor tricks instead (which don't have exactly the right
 180    semantics, but it's the best we can do).
 181
 182    Example:
 183    int __REDIRECT(setpgrp, (__pid_t pid, __pid_t pgrp), setpgid); */
 184
 185 #if defined __GNUC__ && __GNUC__ >= 2
 186
 187 # define __REDIRECT(name, proto, alias) name proto __asm__ (__ASMNAME (#alias))
 188 # ifdef __cplusplus
 189 #  define __REDIRECT_NTH(name, proto, alias) \
 190      name proto __THROW __asm__ (__ASMNAME (#alias))
 191 #  define __REDIRECT_NTHNL(name, proto, alias) \
 192      name proto __THROWNL __asm__ (__ASMNAME (#alias))
 193 # else
 194 #  define __REDIRECT_NTH(name, proto, alias) \
 195      name proto __asm__ (__ASMNAME (#alias)) __THROW
 196 #  define __REDIRECT_NTHNL(name, proto, alias) \
 197      name proto __asm__ (__ASMNAME (#alias)) __THROWNL
 198 # endif
 199 # define __ASMNAME(cname)  __ASMNAME2 (__USER_LABEL_PREFIX__, cname)
 200 # define __ASMNAME2(prefix, cname) __STRING (prefix) cname
 201
 202 /*
 203 #elif __SOME_OTHER_COMPILER__
 204
 205 # define __REDIRECT(name, proto, alias) name proto; \
 206         _Pragma("let " #name " = " #alias)
 207 */
 208 #endif
 209
 210 /* GCC has various useful declarations that can be made with the
 211    `__attribute__' syntax.  All of the ways we use this do fine if
 212    they are omitted for compilers that don't understand it. */
 213 #if !defined __GNUC__ || __GNUC__ < 2
 214 # define __attribute__(xyz)     /* Ignore */
 215 #endif
 216
 217 /* At some point during the gcc 2.96 development the `malloc' 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_malloc__ __attribute__ ((__malloc__))
 222 #else
 223 # define __attribute_malloc__ /* Ignore */
 224 #endif
 225
 226 /* At some point during the gcc 2.96 development the `pure' attribute
 227    for functions was introduced.  We don't want to use it unconditionally
 228    (although this would be possible) since it generates warnings.  */
 229 #if __GNUC_PREREQ (2,96)
 230 # define __attribute_pure__ __attribute__ ((__pure__))
 231 #else
 232 # define __attribute_pure__ /* Ignore */
 233 #endif
 234
 235 /* This declaration tells the compiler that the value is constant.  */
 236 #if __GNUC_PREREQ (2,5)
 237 # define __attribute_const__ __attribute__ ((__const__))
 238 #else
 239 # define __attribute_const__ /* Ignore */
 240 #endif
 241
 242 /* At some point during the gcc 3.1 development the `used' attribute
 243    for functions was introduced.  We don't want to use it unconditionally
 244    (although this would be possible) since it generates warnings.  */
 245 #if __GNUC_PREREQ (3,1)
 246 # define __attribute_used__ __attribute__ ((__used__))
 247 # define __attribute_noinline__ __attribute__ ((__noinline__))
 248 #else
 249 # define __attribute_used__ __attribute__ ((__unused__))
 250 # define __attribute_noinline__ /* Ignore */
 251 #endif
 252
 253 /* gcc allows marking deprecated functions.  */
 254 #if __GNUC_PREREQ (3,2)
 255 # define __attribute_deprecated__ __attribute__ ((__deprecated__))
 256 #else
 257 # define __attribute_deprecated__ /* Ignore */
 258 #endif
 259
 260 /* At some point during the gcc 2.8 development the `format_arg' attribute
 261    for functions was introduced.  We don't want to use it unconditionally
 262    (although this would be possible) since it generates warnings.
 263    If several `format_arg' attributes are given for the same function, in
 264    gcc-3.0 and older, all but the last one are ignored.  In newer gccs,
 265    all designated arguments are considered.  */
 266 #if __GNUC_PREREQ (2,8)
 267 # define __attribute_format_arg__(x) __attribute__ ((__format_arg__ (x)))
 268 #else
 269 # define __attribute_format_arg__(x) /* Ignore */
 270 #endif
 271
 272 /* At some point during the gcc 2.97 development the `strfmon' format
 273    attribute for functions was introduced.  We don't want to use it
 274    unconditionally (although this would be possible) since it
 275    generates warnings.  */
 276 #if __GNUC_PREREQ (2,97)
 277 # define __attribute_format_strfmon__(a,b) \
 278   __attribute__ ((__format__ (__strfmon__, a, b)))
 279 #else
 280 # define __attribute_format_strfmon__(a,b) /* Ignore */
 281 #endif
 282
 283 /* The nonull function attribute allows to mark pointer parameters which
 284    must not be NULL.  */
 285 #if __GNUC_PREREQ (3,3)
 286 # define __nonnull(params) __attribute__ ((__nonnull__ params))
 287 #else
 288 # define __nonnull(params)
 289 #endif
 290
 291 /* If fortification mode, we warn about unused results of certain
 292    function calls which can lead to problems.  */
 293 #if __GNUC_PREREQ (3,4)
 294 # define __attribute_warn_unused_result__ \
 295    __attribute__ ((__warn_unused_result__))
 296 # if __USE_FORTIFY_LEVEL > 0
 297 #  define __wur __attribute_warn_unused_result__
 298 # endif
 299 #else
 300 # define __attribute_warn_unused_result__ /* empty */
 301 #endif
 302 #ifndef __wur
 303 # define __wur /* Ignore */
 304 #endif
 305
 306 /* Forces a function to be always inlined.  */
 307 #if __GNUC_PREREQ (3,2)
 308 # define __always_inline __inline __attribute__ ((__always_inline__))
 309 #else
 310 # define __always_inline __inline
 311 #endif
 312
 313 /* Associate error messages with the source location of the call site rather
 314    than with the source location inside the function.  */
 315 #if __GNUC_PREREQ (4,3)
 316 # define __attribute_artificial__ __attribute__ ((__artificial__))
 317 #else
 318 # define __attribute_artificial__ /* Ignore */
 319 #endif
 320
 321 /* GCC 4.3 and above with -std=c99 or -std=gnu99 implements ISO C99
 322    inline semantics, unless -fgnu89-inline is used.  */
 323 #if (!defined __cplusplus || __GNUC_PREREQ (4,3)) && defined __GNUC__
 324 # if defined __GNUC_STDC_INLINE__ || defined __cplusplus
 325 #  define __extern_inline extern __inline __attribute__ ((__gnu_inline__))
 326 #  define __extern_always_inline \
 327   extern __always_inline __attribute__ ((__gnu_inline__))
 328 # else
 329 #  define __extern_inline extern __inline
 330 #  define __extern_always_inline extern __always_inline
 331 # endif
 332 #elif defined __GNUC__ /* C++ and GCC <4.3.  */
 333 # define __extern_inline extern __inline
 334 # define __extern_always_inline \
 335   extern __always_inline
 336 #else /* Not GCC.  */
 337 # define __extern_inline  /* Ignore */
 338 # define __extern_always_inline /* Ignore */
 339 #endif
 340
 341 /* GCC 4.3 and above allow passing all anonymous arguments of an
 342    __extern_always_inline function to some other vararg function.  */
 343 #if __GNUC_PREREQ (4,3)
 344 # define __va_arg_pack() __builtin_va_arg_pack ()
 345 # define __va_arg_pack_len() __builtin_va_arg_pack_len ()
 346 #endif
 347
 348 /* It is possible to compile containing GCC extensions even if GCC is
 349    run in pedantic mode if the uses are carefully marked using the
 350    `__extension__' keyword.  But this is not generally available before
 351    version 2.8.  */
 352 #if !__GNUC_PREREQ (2,8)
 353 # define __extension__          /* Ignore */
 354 #endif
 355
 356 /* __restrict is known in EGCS 1.2 and above. */
 357 #if !__GNUC_PREREQ (2,92)
 358 # define __restrict     /* Ignore */
 359 #endif
 360
 361 /* ISO C99 also allows to declare arrays as non-overlapping.  The syntax is
 362      array_name[restrict]
 363    GCC 3.1 supports this.  */
 364 #if __GNUC_PREREQ (3,1) && !defined __GNUG__
 365 # define __restrict_arr __restrict
 366 #else
 367 # ifdef __GNUC__
 368 #  define __restrict_arr        /* Not supported in old GCC.  */
 369 # else
 370 #  if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
 371 #   define __restrict_arr       restrict
 372 #  else
 373 /* Some other non-C99 compiler.  */
 374 #   define __restrict_arr       /* Not supported.  */
 375 #  endif
 376 # endif
 377 #endif
 378
 379 #if __GNUC__ >= 3
 380 # define __glibc_unlikely(cond) __builtin_expect((cond), 0)
 381 #else
 382 # define __glibc_unlikely(cond) (cond)
 383 #endif
 384
 385 #include <bits/wordsize.h>
 386
 387 #if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
 388 # define __LDBL_COMPAT 1
 389 # ifdef __REDIRECT
 390 #  define __LDBL_REDIR1(name, proto, alias) __REDIRECT (name, proto, alias)
 391 #  define __LDBL_REDIR(name, proto) \
 392   __LDBL_REDIR1 (name, proto, __nldbl_##name)
 393 #  define __LDBL_REDIR1_NTH(name, proto, alias) __REDIRECT_NTH (name, proto, alias)
 394 #  define __LDBL_REDIR_NTH(name, proto) \
 395   __LDBL_REDIR1_NTH (name, proto, __nldbl_##name)
 396 #  define __LDBL_REDIR1_DECL(name, alias) \
 397   extern __typeof (name) name __asm (__ASMNAME (#alias));
 398 #  define __LDBL_REDIR_DECL(name) \
 399   extern __typeof (name) name __asm (__ASMNAME ("__nldbl_" #name));
 400 #  define __REDIRECT_LDBL(name, proto, alias) \
 401   __LDBL_REDIR1 (name, proto, __nldbl_##alias)
 402 #  define __REDIRECT_NTH_LDBL(name, proto, alias) \
 403   __LDBL_REDIR1_NTH (name, proto, __nldbl_##alias)
 404 # endif
 405 #endif
 406 #if !defined __LDBL_COMPAT || !defined __REDIRECT
 407 # define __LDBL_REDIR1(name, proto, alias) name proto
 408 # define __LDBL_REDIR(name, proto) name proto
 409 # define __LDBL_REDIR1_NTH(name, proto, alias) name proto __THROW
 410 # define __LDBL_REDIR_NTH(name, proto) name proto __THROW
 411 # define __LDBL_REDIR_DECL(name)
 412 # ifdef __REDIRECT
 413 #  define __REDIRECT_LDBL(name, proto, alias) __REDIRECT (name, proto, alias)
 414 #  define __REDIRECT_NTH_LDBL(name, proto, alias) \
 415   __REDIRECT_NTH (name, proto, alias)
 416 # endif
 417 #endif
 418
 419 #endif   /* sys/cdefs.h */