1/* Copyright (C) 1992-2001, 2002 Free Software Foundation, Inc. 2 This file is part of the GNU C Library. 3 4 The GNU C Library is free software; you can redistribute it and/or 5 modify it under the terms of the GNU Lesser General Public 6 License as published by the Free Software Foundation; either 7 version 2.1 of the License, or (at your option) any later version. 8 9 The GNU C Library is distributed in the hope that it will be useful, 10 but WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 Lesser General Public License for more details. 13 14 You should have received a copy of the GNU Lesser General Public 15 License along with the GNU C Library; if not, write to the Free 16 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 17 02111-1307 USA. */ 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/* GCC can always grok prototypes. For C++ programs we add throw() 41 to help it optimize the function calls. But this works only with 42 gcc 2.8.x and egcs. */ 43# if defined __cplusplus && __GNUC_PREREQ (2,8) 44# define __THROW throw () 45# else 46# define __THROW 47# endif 48# define __P(args) args __THROW 49/* This macro will be used for functions which might take C++ callback 50 functions. */ 51# define __PMT(args) args 52 53#else /* Not GCC. */ 54 55# define __inline /* No inline functions. */ 56 57# define __THROW 58# define __P(args) args 59# define __PMT(args) args 60 61# define __const const 62# define __signed signed 63# define __volatile volatile 64 65#endif /* GCC. */ 66 67/* For these things, GCC behaves the ANSI way normally, 68 and the non-ANSI way under -traditional. */ 69 70#define __CONCAT(x,y) x ## y 71#define __STRING(x) #x 72 73/* This is not a typedef so `const __ptr_t' does the right thing. */ 74#define __ptr_t void * 75#define __long_double_t long double 76 77 78/* C++ needs to know that types and declarations are C, not C++. */ 79#ifdef __cplusplus 80# define __BEGIN_DECLS extern "C" { 81# define __END_DECLS } 82#else 83# define __BEGIN_DECLS 84# define __END_DECLS 85#endif 86 87 88/* The standard library needs the functions from the ISO C90 standard 89 in the std namespace. At the same time we want to be safe for 90 future changes and we include the ISO C99 code in the non-standard 91 namespace __c99. The C++ wrapper header take case of adding the 92 definitions to the global namespace. */ 93#if defined __cplusplus && defined _GLIBCPP_USE_NAMESPACES 94# define __BEGIN_NAMESPACE_STD namespace std { 95# define __END_NAMESPACE_STD } 96# define __USING_NAMESPACE_STD(name) using std::name; 97# define __BEGIN_NAMESPACE_C99 namespace __c99 { 98# define __END_NAMESPACE_C99 } 99# define __USING_NAMESPACE_C99(name) using __c99::name; 100#else 101/* For compatibility we do not add the declarations into any 102 namespace. They will end up in the global namespace which is what 103 old code expects. */ 104# define __BEGIN_NAMESPACE_STD 105# define __END_NAMESPACE_STD 106# define __USING_NAMESPACE_STD(name) 107# define __BEGIN_NAMESPACE_C99 108# define __END_NAMESPACE_C99 109# define __USING_NAMESPACE_C99(name) 110#endif 111 112 113/* Support for bounded pointers. */ 114#ifndef __BOUNDED_POINTERS__ 115# define __bounded /* nothing */ 116# define __unbounded /* nothing */ 117# define __ptrvalue /* nothing */ 118#endif 119 120 121/* Support for flexible arrays. */ 122#if __GNUC_PREREQ (2,97) 123/* GCC 2.97 supports C99 flexible array members. */ 124# define __flexarr [] 125#else 126# ifdef __GNUC__ 127# define __flexarr [0] 128# else 129# if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L 130# define __flexarr [] 131# else 132/* Some other non-C99 compiler. Approximate with [1]. */ 133# define __flexarr [1] 134# endif 135# endif 136#endif 137 138 139/* __asm__ ("xyz") is used throughout the headers to rename functions 140 at the assembly language level. This is wrapped by the __REDIRECT 141 macro, in order to support compilers that can do this some other 142 way. When compilers don't support asm-names at all, we have to do 143 preprocessor tricks instead (which don't have exactly the right 144 semantics, but it's the best we can do). 145 146 Example: 147 int __REDIRECT(setpgrp, (__pid_t pid, __pid_t pgrp), setpgid); */ 148 149#if defined __GNUC__ && __GNUC__ >= 2 150 151# define __REDIRECT(name, proto, alias) name proto __asm__ (__ASMNAME (#alias)) 152# define __ASMNAME(cname) __ASMNAME2 (__USER_LABEL_PREFIX__, cname) 153# define __ASMNAME2(prefix, cname) __STRING (prefix) cname 154 155/* 156#elif __SOME_OTHER_COMPILER__ 157 158# define __REDIRECT(name, proto, alias) name proto; \ 159 _Pragma("let " #name " = " #alias) 160*/ 161#endif 162 163/* GCC has various useful declarations that can be made with the 164 `__attribute__' syntax. All of the ways we use this do fine if 165 they are omitted for compilers that don't understand it. */ 166#if !defined __GNUC__ || __GNUC__ < 2 167# define __attribute__(xyz) /* Ignore */ 168#endif 169 170/* At some point during the gcc 2.96 development the `malloc' attribute 171 for functions was introduced. We don't want to use it unconditionally 172 (although this would be possible) since it generates warnings. */ 173#if __GNUC_PREREQ (2,96) 174# define __attribute_malloc__ __attribute__ ((__malloc__)) 175#else 176# define __attribute_malloc__ /* Ignore */ 177#endif 178 179/* At some point during the gcc 2.96 development the `pure' attribute 180 for functions was introduced. We don't want to use it unconditionally 181 (although this would be possible) since it generates warnings. */ 182#if __GNUC_PREREQ (2,96) 183# define __attribute_pure__ __attribute__ ((__pure__)) 184#else 185# define __attribute_pure__ /* Ignore */ 186#endif 187 188/* At some point during the gcc 3.1 development the `used' attribute 189 for functions was introduced. We don't want to use it unconditionally 190 (although this would be possible) since it generates warnings. */ 191#if __GNUC_PREREQ (3,1) 192# define __attribute_used__ __attribute__ ((__used__)) 193# define __attribute_noinline__ __attribute__ ((__noinline__)) 194#else 195# define __attribute_used__ __attribute__ ((__unused__)) 196# define __attribute_noinline__ /* Ignore */ 197#endif 198 199/* gcc allows marking deprecated functions. */ 200#if __GNUC_PREREQ (3,2) 201# define __attribute_deprecated__ __attribute__ ((__deprecated__)) 202#else 203# define __attribute_deprecated__ /* Ignore */ 204#endif 205 206/* At some point during the gcc 2.8 development the `format_arg' attribute 207 for functions was introduced. We don't want to use it unconditionally 208 (although this would be possible) since it generates warnings. 209 If several `format_arg' attributes are given for the same function, in 210 gcc-3.0 and older, all but the last one are ignored. In newer gccs, 211 all designated arguments are considered. */ 212#if __GNUC_PREREQ (2,8) 213# define __attribute_format_arg__(x) __attribute__ ((__format_arg__ (x))) 214#else 215# define __attribute_format_arg__(x) /* Ignore */ 216#endif 217 218/* At some point during the gcc 2.97 development the `strfmon' format 219 attribute for functions was introduced. We don't want to use it 220 unconditionally (although this would be possible) since it 221 generates warnings. */ 222#if __GNUC_PREREQ (2,97) 223# define __attribute_format_strfmon__(a,b) \ 224 __attribute__ ((__format__ (__strfmon__, a, b))) 225#else 226# define __attribute_format_strfmon__(a,b) /* Ignore */ 227#endif 228 229 230/* Forces a function to be always inlined. */ 231#if __GNUC_PREREQ (3,2) 232# define __always_inline __inline __attribute__ ((__always_inline__)) 233#else 234# define __always_inline __inline 235#endif 236 237/* Associate error messages with the source location of the call site rather 238 than with the source location inside the function. */ 239#if __GNUC_PREREQ (4,3) 240# define __attribute_artificial__ __attribute__ ((__artificial__)) 241#else 242# define __attribute_artificial__ /* Ignore */ 243#endif 244 245/* GCC 4.3 and above with -std=c99 or -std=gnu99 implements ISO C99 246 inline semantics, unless -fgnu89-inline is used. */ 247#if !defined __cplusplus || __GNUC_PREREQ (4,3) 248# if defined __GNUC_STDC_INLINE__ || defined __cplusplus 249# define __extern_inline extern __inline __attribute__ ((__gnu_inline__)) 250# define __extern_always_inline \ 251 extern __always_inline __attribute__ ((__gnu_inline__)) 252# else 253# define __extern_inline extern __inline 254# define __extern_always_inline extern __always_inline 255# endif 256#else 257# define __extern_inline extern __inline 258#endif 259 260 261/* It is possible to compile containing GCC extensions even if GCC is 262 run in pedantic mode if the uses are carefully marked using the 263 `__extension__' keyword. But this is not generally available before 264 version 2.8. */ 265#if !__GNUC_PREREQ (2,8) 266# define __extension__ /* Ignore */ 267#endif 268 269/* __restrict is known in EGCS 1.2 and above. */ 270#if !__GNUC_PREREQ (2,92) 271# define __restrict /* Ignore */ 272#endif 273 274/* ISO C99 also allows to declare arrays as non-overlapping. The syntax is 275 array_name[restrict] 276 GCC 3.1 supports this. */ 277#if __GNUC_PREREQ (3,1) && !defined __GNUG__ 278# define __restrict_arr __restrict 279#else 280# ifdef __GNUC__ 281# define __restrict_arr /* Not supported in old GCC. */ 282# else 283# if defined __STDC_VERSION__ && __STDC_VERSION__ >= 199901L 284# define __restrict_arr restrict 285# else 286/* Some other non-C99 compiler. */ 287# define __restrict_arr /* Not supported. */ 288# endif 289# endif 290#endif 291 292#endif /* sys/cdefs.h */ 293