misc/sys/cdefs.h

   1 /* Copyright (C) 1992-2001, 2002, 2004, 2005, 2006
   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 #define __warndecl(name, msg) extern void name (void)
 135
 136
 137 /* Support for flexible arrays.  */
 138 #if __GNUC_PREREQ (2,97)
 139 /* GCC 2.97 supports C99 flexible array members.  */
 140 # define __flexarr      []
 141 #else
 142 # ifdef __GNUC__
 143 #  define __flexarr     [0]
 144 # else
 145 #  if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
 146 #   define __flexarr    []
 147 #  else
 148 /* Some other non-C99 compiler.  Approximate with [1].  */
 149 #   define __flexarr    [1]
 150 #  endif
 151 # endif
 152 #endif
 153
 154
 155 /* __asm__ ("xyz") is used throughout the headers to rename functions
 156    at the assembly language level.  This is wrapped by the __REDIRECT
 157    macro, in order to support compilers that can do this some other
 158    way.  When compilers don't support asm-names at all, we have to do
 159    preprocessor tricks instead (which don't have exactly the right
 160    semantics, but it's the best we can do).
 161
 162    Example:
 163    int __REDIRECT(setpgrp, (__pid_t pid, __pid_t pgrp), setpgid); */
 164
 165 #if defined __GNUC__ && __GNUC__ >= 2
 166
 167 # define __REDIRECT(name, proto, alias) name proto __asm__ (__ASMNAME (#alias))
 168 # ifdef __cplusplus
 169 #  define __REDIRECT_NTH(name, proto, alias) \
 170      name proto __THROW __asm__ (__ASMNAME (#alias))
 171 # else
 172 #  define __REDIRECT_NTH(name, proto, alias) \
 173      name proto __asm__ (__ASMNAME (#alias)) __THROW
 174 # endif
 175 # define __ASMNAME(cname)  __ASMNAME2 (__USER_LABEL_PREFIX__, cname)
 176 # define __ASMNAME2(prefix, cname) __STRING (prefix) cname
 177
 178 /*
 179 #elif __SOME_OTHER_COMPILER__
 180
 181 # define __REDIRECT(name, proto, alias) name proto; \
 182         _Pragma("let " #name " = " #alias)
 183 */
 184 #endif
 185
 186 /* GCC has various useful declarations that can be made with the
 187    `__attribute__' syntax.  All of the ways we use this do fine if
 188    they are omitted for compilers that don't understand it. */
 189 #if !defined __GNUC__ || __GNUC__ < 2
 190 # define __attribute__(xyz)     /* Ignore */
 191 #endif
 192
 193 /* At some point during the gcc 2.96 development the `malloc' attribute
 194    for functions was introduced.  We don't want to use it unconditionally
 195    (although this would be possible) since it generates warnings.  */
 196 #if __GNUC_PREREQ (2,96)
 197 # define __attribute_malloc__ __attribute__ ((__malloc__))
 198 #else
 199 # define __attribute_malloc__ /* Ignore */
 200 #endif
 201
 202 /* At some point during the gcc 2.96 development the `pure' attribute
 203    for functions was introduced.  We don't want to use it unconditionally
 204    (although this would be possible) since it generates warnings.  */
 205 #if __GNUC_PREREQ (2,96)
 206 # define __attribute_pure__ __attribute__ ((__pure__))
 207 #else
 208 # define __attribute_pure__ /* Ignore */
 209 #endif
 210
 211 /* At some point during the gcc 3.1 development the `used' attribute
 212    for functions was introduced.  We don't want to use it unconditionally
 213    (although this would be possible) since it generates warnings.  */
 214 #if __GNUC_PREREQ (3,1)
 215 # define __attribute_used__ __attribute__ ((__used__))
 216 # define __attribute_noinline__ __attribute__ ((__noinline__))
 217 #else
 218 # define __attribute_used__ __attribute__ ((__unused__))
 219 # define __attribute_noinline__ /* Ignore */
 220 #endif
 221
 222 /* gcc allows marking deprecated functions.  */
 223 #if __GNUC_PREREQ (3,2)
 224 # define __attribute_deprecated__ __attribute__ ((__deprecated__))
 225 #else
 226 # define __attribute_deprecated__ /* Ignore */
 227 #endif
 228
 229 /* At some point during the gcc 2.8 development the `format_arg' attribute
 230    for functions was introduced.  We don't want to use it unconditionally
 231    (although this would be possible) since it generates warnings.
 232    If several `format_arg' attributes are given for the same function, in
 233    gcc-3.0 and older, all but the last one are ignored.  In newer gccs,
 234    all designated arguments are considered.  */
 235 #if __GNUC_PREREQ (2,8)
 236 # define __attribute_format_arg__(x) __attribute__ ((__format_arg__ (x)))
 237 #else
 238 # define __attribute_format_arg__(x) /* Ignore */
 239 #endif
 240
 241 /* At some point during the gcc 2.97 development the `strfmon' format
 242    attribute for functions was introduced.  We don't want to use it
 243    unconditionally (although this would be possible) since it
 244    generates warnings.  */
 245 #if __GNUC_PREREQ (2,97)
 246 # define __attribute_format_strfmon__(a,b) \
 247   __attribute__ ((__format__ (__strfmon__, a, b)))
 248 #else
 249 # define __attribute_format_strfmon__(a,b) /* Ignore */
 250 #endif
 251
 252 /* The nonull function attribute allows to mark pointer parameters which
 253    must not be NULL.  */
 254 #if __GNUC_PREREQ (3,3)
 255 # define __nonnull(params) __attribute__ ((__nonnull__ params))
 256 #else
 257 # define __nonnull(params)
 258 #endif
 259
 260 /* If fortification mode, we warn about unused results of certain
 261    function calls which can lead to problems.  */
 262 #if __GNUC_PREREQ (3,4)
 263 # define __attribute_warn_unused_result__ \
 264    __attribute__ ((__warn_unused_result__))
 265 # if __USE_FORTIFY_LEVEL > 0
 266 #  define __wur __attribute_warn_unused_result__
 267 # endif
 268 #else
 269 # define __attribute_warn_unused_result__ /* empty */
 270 #endif
 271 #ifndef __wur
 272 # define __wur /* Ignore */
 273 #endif
 274
 275 /* Forces a function to be always inlined.  */
 276 #if __GNUC_PREREQ (3,2)
 277 # define __always_inline __inline __attribute__ ((__always_inline__))
 278 #else
 279 # define __always_inline __inline
 280 #endif
 281
 282 /* It is possible to compile containing GCC extensions even if GCC is
 283    run in pedantic mode if the uses are carefully marked using the
 284    `__extension__' keyword.  But this is not generally available before
 285    version 2.8.  */
 286 #if !__GNUC_PREREQ (2,8)
 287 # define __extension__          /* Ignore */
 288 #endif
 289
 290 /* __restrict is known in EGCS 1.2 and above. */
 291 #if !__GNUC_PREREQ (2,92)
 292 # define __restrict     /* Ignore */
 293 #endif
 294
 295 /* ISO C99 also allows to declare arrays as non-overlapping.  The syntax is
 296      array_name[restrict]
 297    GCC 3.1 supports this.  */
 298 #if __GNUC_PREREQ (3,1) && !defined __GNUG__
 299 # define __restrict_arr __restrict
 300 #else
 301 # ifdef __GNUC__
 302 #  define __restrict_arr        /* Not supported in old GCC.  */
 303 # else
 304 #  if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L
 305 #   define __restrict_arr       restrict
 306 #  else
 307 /* Some other non-C99 compiler.  */
 308 #   define __restrict_arr       /* Not supported.  */
 309 #  endif
 310 # endif
 311 #endif
 312
 313 #include <bits/wordsize.h>
 314
 315 #if defined __LONG_DOUBLE_MATH_OPTIONAL && defined __NO_LONG_DOUBLE_MATH
 316 # define __LDBL_COMPAT 1
 317 # ifdef __REDIRECT
 318 #  define __LDBL_REDIR1(name, proto, alias) __REDIRECT (name, proto, alias)
 319 #  define __LDBL_REDIR(name, proto) \
 320   __LDBL_REDIR1 (name, proto, __nldbl_##name)
 321 #  define __LDBL_REDIR1_NTH(name, proto, alias) __REDIRECT_NTH (name, proto, alias)
 322 #  define __LDBL_REDIR_NTH(name, proto) \
 323   __LDBL_REDIR1_NTH (name, proto, __nldbl_##name)
 324 #  define __LDBL_REDIR_DECL(name) \
 325   extern __typeof (name) name __asm (__ASMNAME (__nldbl_##name));
 326 # endif
 327 #endif
 328 #if !defined __LDBL_COMPAT || !defined __REDIRECT
 329 # define __LDBL_REDIR1(name, proto, alias) name proto
 330 # define __LDBL_REDIR(name, proto) name proto
 331 # define __LDBL_REDIR1_NTH(name, proto, alias) name proto __THROW
 332 # define __LDBL_REDIR_NTH(name, proto) name proto __THROW
 333 # define __LDBL_REDIR_DECL(name)
 334 #endif
 335
 336 #endif   /* sys/cdefs.h */