misc/sys/cdefs.h

   1 /* Copyright (C) 1992-2001, 2002, 2004, 2005, 2006, 2007
   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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #ifndef _SYS_CDEFS_H
  21 #define _SYS_CDEFS_H    1
  22
  23 /* We are almost always included from features.h. */
  24 #ifndef _FEATURES_H
  25 # include <features.h>
  26 #endif
  27
  28 /* The GNU libc does not support any K&R compilers or the traditional mode
  29    of ISO C compilers anymore.  Check for some of the combinations not
  30    anymore supported.  */
  31 #if defined __GNUC__ && !defined __STDC__
  32 # error "You need a ISO C conforming compiler to use the glibc headers"
  33 #endif
  34
  35 /* Some user header file might have defined this before.  */
  36 #undef  __P
  37 #undef  __PMT
  38
  39 #ifdef __GNUC__
  40
  41 /* GCC can always grok prototypes.  For C++ programs we add throw()
  42    to help it optimize the function calls.  But this works only with
  43    gcc 2.8.x and egcs.  For gcc 3.2 and up we even mark C functions
  44    as non-throwing using a function attribute since programs can use
  45    the -fexceptions options for C code as well.  */
  46 # if !defined __cplusplus && __GNUC_PREREQ (3, 3)
  47 #  define __THROW       __attribute__ ((__nothrow__))
  48 #  define __NTH(fct)    __attribute__ ((__nothrow__)) fct
  49 # else
  50 #  if defined __cplusplus && __GNUC_PREREQ (2,8)
  51 #   define __THROW      throw ()
  52 #   define __NTH(fct)   fct throw ()
  53 #  else
  54 #   define __THROW
  55 #   define __NTH(fct)   fct
  56 #  endif
  57 # endif
  58
  59 #else   /* Not GCC.  */
  60
  61 # define __inline               /* No inline functions.  */
  62
  63 # define __THROW
  64 # define __NTH(fct)     fct
  65
  66 # define __const        const
  67 # define __signed       signed
  68 # define __volatile     volatile
  69
  70 #endif  /* GCC.  */
  71
  72 /* These two macros are not used in glibc anymore.  They are kept here
  73    only because some other projects expect the macros to be defined.  */
  74 #define __P(args)       args
  75 #define __PMT(args)     args
  76
  77 /* For these things, GCC behaves the ANSI way normally,
  78    and the non-ANSI way under -traditional.  */
  79
  80 #define __CONCAT(x,y)   x ## y
  81 #define __STRING(x)     #x
  82
  83 /* This is not a typedef so `const __ptr_t' does the right thing.  */
  84 #define __ptr_t void *
  85 #define __long_double_t  long double
  86
  87
  88 /* C++ needs to know that types and declarations are C, not C++.  */
  89 #ifdef  __cplusplus
  90 # define __BEGIN_DECLS  extern "C" {
  91 # define __END_DECLS    }
  92 #else
  93 # define __BEGIN_DECLS
  94 # define __END_DECLS
  95 #endif
  96
  97
  98 /* The standard library needs the functions from the ISO C90 standard
  99    in the std namespace.  At the same time we want to be safe for
 100    future changes and we include the ISO C99 code in the non-standard
 101    namespace __c99.  The C++ wrapper header take case of adding the
 102    definitions to the global namespace.  */
 103 #if defined __cplusplus && defined _GLIBCPP_USE_NAMESPACES
 104 # define __BEGIN_NAMESPACE_STD  namespace std {
 105 # define __END_NAMESPACE_STD    }
 106 # define __USING_NAMESPACE_STD(name) using std::name;
 107 # define __BEGIN_NAMESPACE_C99  namespace __c99 {
 108 # define __END_NAMESPACE_C99    }
 109 # define __USING_NAMESPACE_C99(name) using __c99::name;
 110 #else
 111 /* For compatibility we do not add the declarations into any
 112    namespace.  They will end up in the global namespace which is what
 113    old code expects.  */
 114 # define __BEGIN_NAMESPACE_STD
 115 # define __END_NAMESPACE_STD
 116 # define __USING_NAMESPACE_STD(name)
 117 # define __BEGIN_NAMESPACE_C99
 118 # define __END_NAMESPACE_C99
 119 # define __USING_NAMESPACE_C99(name)
 120 #endif
 121
 122
 123 /* Support for bounded pointers.  */
 124 #ifndef __BOUNDED_POINTERS__
 125 # define __bounded      /* nothing */
 126 # define __unbounded    /* nothing */
 127 # define __ptrvalue     /* nothing */
 128 #endif
 129
 130
 131 /* Fortify support.  */
 132 #define __bos(ptr) __builtin_object_size (ptr, __USE_FORTIFY_LEVEL > 1)
 133 #define __bos0(ptr) __builtin_object_size (ptr, 0)
 134
 135 #if __GNUC_PREREQ (4,3)
 136 # define __warndecl(name, msg) \
 137   extern void name (void) __attribute__((__warning__ (msg)))
 138 # define __warnattr(msg) __attribute__((__warning__ (msg)))
 139 # define __errordecl(name, msg) \
 140   extern void name (void) __attribute__((__error__ (msg)))
 141 #else
 142 # define __warndecl(name, msg) extern void name (void)
 143 # define __warnattr(msg)
 144 # define __errordecl(name, msg) extern void name (void)
 145 #endif
 146
 147 /* Support for flexible arrays.  */
 148 #if __GNUC_PREREQ (2,97)
 149 /* GCC 2.97 supports C99 flexible array members.  */
 150 # define __flexarr      []
 151 #else
 152 # ifdef __GNUC__
 153 #  define __flexarr     [0]
 154 # else
 155 #  if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
 156 #   define __flexarr    []
 157 #  else
 158 /* Some other non-C99 compiler.  Approximate with [1].  */
 159 #   define __flexarr    [1]
 160 #  endif
 161 # endif
 162 #endif
 163
 164
 165 /* __asm__ ("xyz") is used throughout the headers to rename functions
 166    at the assembly language level.  This is wrapped by the __REDIRECT
 167    macro, in order to support compilers that can do this some other
 168    way.  When compilers don't support asm-names at all, we have to do
 169    preprocessor tricks instead (which don't have exactly the right
 170    semantics, but it's the best we can do).
 171
 172    Example:
 173    int __REDIRECT(setpgrp, (__pid_t pid, __pid_t pgrp), setpgid); */
 174
 175 #if defined __GNUC__ && __GNUC__ >= 2
 176
 177 # define __REDIRECT(name, proto, alias) name proto __asm__ (__ASMNAME (#alias))
 178 # ifdef __cplusplus
 179 #  define __REDIRECT_NTH(name, proto, alias) \
 180      name proto __THROW __asm__ (__ASMNAME (#alias))
 181 # else
 182 #  define __REDIRECT_NTH(name, proto, alias) \
 183      name proto __asm__ (__ASMNAME (#alias)) __THROW
 184 # endif
 185 # define __ASMNAME(cname)  __ASMNAME2 (__USER_LABEL_PREFIX__, cname)
 186 # define __ASMNAME2(prefix, cname) __STRING (prefix) cname
 187
 188 /*
 189 #elif __SOME_OTHER_COMPILER__
 190
 191 # define __REDIRECT(name, proto, alias) name proto; \
 192         _Pragma("let " #name " = " #alias)
 193 */
 194 #endif
 195
 196 /* GCC has various useful declarations that can be made with the
 197    `__attribute__' syntax.  All of the ways we use this do fine if
 198    they are omitted for compilers that don't understand it. */
 199 #if !defined __GNUC__ || __GNUC__ < 2
 200 # define __attribute__(xyz)     /* Ignore */
 201 #endif
 202
 203 /* At some point during the gcc 2.96 development the `malloc' attribute
 204    for functions was introduced.  We don't want to use it unconditionally
 205    (although this would be possible) since it generates warnings.  */
 206 #if __GNUC_PREREQ (2,96)
 207 # define __attribute_malloc__ __attribute__ ((__malloc__))
 208 #else
 209 # define __attribute_malloc__ /* Ignore */
 210 #endif
 211
 212 /* At some point during the gcc 2.96 development the `pure' attribute
 213    for functions was introduced.  We don't want to use it unconditionally
 214    (although this would be possible) since it generates warnings.  */
 215 #if __GNUC_PREREQ (2,96)
 216 # define __attribute_pure__ __attribute__ ((__pure__))
 217 #else
 218 # define __attribute_pure__ /* Ignore */
 219 #endif
 220
 221 /* At some point during the gcc 3.1 development the `used' attribute
 222    for functions was introduced.  We don't want to use it unconditionally
 223    (although this would be possible) since it generates warnings.  */
 224 #if __GNUC_PREREQ (3,1)
 225 # define __attribute_used__ __attribute__ ((__used__))
 226 # define __attribute_noinline__ __attribute__ ((__noinline__))
 227 #else
 228 # define __attribute_used__ __attribute__ ((__unused__))
 229 # define __attribute_noinline__ /* Ignore */
 230 #endif
 231
 232 /* gcc allows marking deprecated functions.  */
 233 #if __GNUC_PREREQ (3,2)
 234 # define __attribute_deprecated__ __attribute__ ((__deprecated__))
 235 #else
 236 # define __attribute_deprecated__ /* Ignore */
 237 #endif
 238
 239 /* At some point during the gcc 2.8 development the `format_arg' attribute
 240    for functions was introduced.  We don't want to use it unconditionally
 241    (although this would be possible) since it generates warnings.
 242    If several `format_arg' attributes are given for the same function, in
 243    gcc-3.0 and older, all but the last one are ignored.  In newer gccs,
 244    all designated arguments are considered.  */
 245 #if __GNUC_PREREQ (2,8)
 246 # define __attribute_format_arg__(x) __attribute__ ((__format_arg__ (x)))
 247 #else
 248 # define __attribute_format_arg__(x) /* Ignore */
 249 #endif
 250
 251 /* At some point during the gcc 2.97 development the `strfmon' format
 252    attribute for functions was introduced.  We don't want to use it
 253    unconditionally (although this would be possible) since it
 254    generates warnings.  */
 255 #if __GNUC_PREREQ (2,97)
 256 # define __attribute_format_strfmon__(a,b) \
 257   __attribute__ ((__format__ (__strfmon__, a, b)))
 258 #else
 259 # define __attribute_format_strfmon__(a,b) /* Ignore */
 260 #endif
 261
 262 /* The nonull function attribute allows to mark pointer parameters which
 263    must not be NULL.  */
 264 #if __GNUC_PREREQ (3,3)
 265 # define __nonnull(params) __attribute__ ((__nonnull__ params))
 266 #else
 267 # define __nonnull(params)
 268 #endif
 269
 270 /* If fortification mode, we warn about unused results of certain
 271    function calls which can lead to problems.  */
 272 #if __GNUC_PREREQ (3,4)
 273 # define __attribute_warn_unused_result__ \
 274    __attribute__ ((__warn_unused_result__))
 275 # if __USE_FORTIFY_LEVEL > 0
 276 #  define __wur __attribute_warn_unused_result__
 277 # endif
 278 #else
 279 # define __attribute_warn_unused_result__ /* empty */
 280 #endif
 281 #ifndef __wur
 282 # define __wur /* Ignore */
 283 #endif
 284
 285 /* Forces a function to be always inlined.  */
 286 #if __GNUC_PREREQ (3,2)
 287 # define __always_inline __inline __attribute__ ((__always_inline__))
 288 #else
 289 # define __always_inline __inline
 290 #endif
 291
 292 /* GCC 4.3 and above with -std=c99 or -std=gnu99 implements ISO C99
 293    inline semantics, unless -fgnu89-inline is used.  */
 294 #if !defined __cplusplus || __GNUC_PREREQ (4,3)
 295 # if defined __GNUC_STDC_INLINE__ || defined __cplusplus
 296 #  define __extern_inline extern __inline __attribute__ ((__gnu_inline__))
 297 #  if __GNUC_PREREQ (4,3)
 298 #   define __extern_always_inline \
 299   extern __always_inline __attribute__ ((__gnu_inline__, __artificial__))
 300 #  else
 301 #   define __extern_always_inline \
 302   extern __always_inline __attribute__ ((__gnu_inline__))
 303 #  endif
 304 # else
 305 #  define __extern_inline extern __inline
 306 #  define __extern_always_inline extern __always_inline
 307 # endif
 308 #endif
 309
 310 /* GCC 4.3 and above allow passing all anonymous arguments of an
 311    __extern_always_inline function to some other vararg function.  */
 312 #if __GNUC_PREREQ (4,3)
 313 # define __va_arg_pack() __builtin_va_arg_pack ()
 314 # define __va_arg_pack_len() __builtin_va_arg_pack_len ()
 315 #endif
 316
 317 /* It is possible to compile containing GCC extensions even if GCC is
 318    run in pedantic mode if the uses are carefully marked using the
 319    `__extension__' keyword.  But this is not generally available before
 320    version 2.8.  */
 321 #if !__GNUC_PREREQ (2,8)
 322 # define __extension__          /* Ignore */
 323 #endif
 324
 325 /* __restrict is known in EGCS 1.2 and above. */
 326 #if !__GNUC_PREREQ (2,92)
 327 # define __restrict     /* Ignore */
 328 #endif
 329
 330 /* ISO C99 also allows to declare arrays as non-overlapping.  The syntax is
 331      array_name[restrict]
 332    GCC 3.1 supports this.  */
 333 #if __GNUC_PREREQ (3,1) && !defined __GNUG__
 334 # define __restrict_arr __restrict
 335 #else
 336 # ifdef __GNUC__
 337 #  define __restrict_arr        /* Not supported in old GCC.  */
 338 # else
 339 #  if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
 340 #   define __restrict_arr       restrict
 341 #  else
 342 /* Some other non-C99 compiler.  */
 343 #   define __restrict_arr       /* Not supported.  */
 344 #  endif
 345 # endif
 346 #endif
 347
 348 #include <bits/wordsize.h>
 349
 350 #if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
 351 # define __LDBL_COMPAT 1
 352 # ifdef __REDIRECT
 353 #  define __LDBL_REDIR1(name, proto, alias) __REDIRECT (name, proto, alias)
 354 #  define __LDBL_REDIR(name, proto) \
 355   __LDBL_REDIR1 (name, proto, __nldbl_##name)
 356 #  define __LDBL_REDIR1_NTH(name, proto, alias) __REDIRECT_NTH (name, proto, alias)
 357 #  define __LDBL_REDIR_NTH(name, proto) \
 358   __LDBL_REDIR1_NTH (name, proto, __nldbl_##name)
 359 #  define __LDBL_REDIR1_DECL(name, alias) \
 360   extern __typeof (name) name __asm (__ASMNAME (#alias));
 361 #  define __LDBL_REDIR_DECL(name) \
 362   extern __typeof (name) name __asm (__ASMNAME ("__nldbl_" #name));
 363 #  define __REDIRECT_LDBL(name, proto, alias) \
 364   __LDBL_REDIR1 (name, proto, __nldbl_##alias)
 365 #  define __REDIRECT_NTH_LDBL(name, proto, alias) \
 366   __LDBL_REDIR1_NTH (name, proto, __nldbl_##alias)
 367 # endif
 368 #endif
 369 #if !defined __LDBL_COMPAT || !defined __REDIRECT
 370 # define __LDBL_REDIR1(name, proto, alias) name proto
 371 # define __LDBL_REDIR(name, proto) name proto
 372 # define __LDBL_REDIR1_NTH(name, proto, alias) name proto __THROW
 373 # define __LDBL_REDIR_NTH(name, proto) name proto __THROW
 374 # define __LDBL_REDIR_DECL(name)
 375 # ifdef __REDIRECT
 376 #  define __REDIRECT_LDBL(name, proto, alias) __REDIRECT (name, proto, alias)
 377 #  define __REDIRECT_NTH_LDBL(name, proto, alias) \
 378   __REDIRECT_NTH (name, proto, alias)
 379 # endif
 380 #endif
 381
 382 #endif   /* sys/cdefs.h */