1 /* ANSI and traditional C compatability macros 2 Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001 3 Free Software Foundation, Inc. 4 This file is part of the GNU C Library. 5 6 This program is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2 of the License, or 9 (at your option) any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program; if not, write to the Free Software 18 Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */ 19 20 /* ANSI and traditional C compatibility macros 21 22 ANSI C is assumed if __STDC__ is #defined. 23 24 Macro ANSI C definition Traditional C definition 25 ----- ---- - ---------- ----------- - ---------- 26 ANSI_PROTOTYPES 1 not defined 27 PTR `void *' `char *' 28 PTRCONST `void *const' `char *' 29 LONG_DOUBLE `long double' `double' 30 const not defined `' 31 volatile not defined `' 32 signed not defined `' 33 VA_START(ap, var) va_start(ap, var) va_start(ap) 34 35 Note that it is safe to write "void foo();" indicating a function 36 with no return value, in all K+R compilers we have been able to test. 37 38 For declaring functions with prototypes, we also provide these: 39 40 PARAMS ((prototype)) 41 -- for functions which take a fixed number of arguments. Use this 42 when declaring the function. When defining the function, write a 43 K+R style argument list. For example: 44 45 char *strcpy PARAMS ((char *dest, char *source)); 46 ... 47 char * 48 strcpy (dest, source) 49 char *dest; 50 char *source; 51 { ... } 52 53 54 VPARAMS ((prototype, ...)) 55 -- for functions which take a variable number of arguments. Use 56 PARAMS to declare the function, VPARAMS to define it. For example: 57 58 int printf PARAMS ((const char *format, ...)); 59 ... 60 int 61 printf VPARAMS ((const char *format, ...)) 62 { 63 ... 64 } 65 66 For writing functions which take variable numbers of arguments, we 67 also provide the VA_OPEN, VA_CLOSE, and VA_FIXEDARG macros. These 68 hide the differences between K+R <varargs.h> and C89 <stdarg.h> more 69 thoroughly than the simple VA_START() macro mentioned above. 70 71 VA_OPEN and VA_CLOSE are used *instead of* va_start and va_end. 72 Immediately after VA_OPEN, put a sequence of VA_FIXEDARG calls 73 corresponding to the list of fixed arguments. Then use va_arg 74 normally to get the variable arguments, or pass your va_list object 75 around. You do not declare the va_list yourself; VA_OPEN does it 76 for you. 77 78 Here is a complete example: 79 80 int 81 printf VPARAMS ((const char *format, ...)) 82 { 83 int result; 84 85 VA_OPEN (ap, format); 86 VA_FIXEDARG (ap, const char *, format); 87 88 result = vfprintf (stdout, format, ap); 89 VA_CLOSE (ap); 90 91 return result; 92 } 93 94 95 You can declare variables either before or after the VA_OPEN, 96 VA_FIXEDARG sequence. Also, VA_OPEN and VA_CLOSE are the beginning 97 and end of a block. They must appear at the same nesting level, 98 and any variables declared after VA_OPEN go out of scope at 99 VA_CLOSE. Unfortunately, with a K+R compiler, that includes the 100 argument list. You can have multiple instances of VA_OPEN/VA_CLOSE 101 pairs in a single function in case you need to traverse the 102 argument list more than once. 103 104 For ease of writing code which uses GCC extensions but needs to be 105 portable to other compilers, we provide the GCC_VERSION macro that 106 simplifies testing __GNUC__ and __GNUC_MINOR__ together, and various 107 wrappers around __attribute__. Also, __extension__ will be #defined 108 to nothing if it doesn't work. See below. 109 110 This header also defines a lot of obsolete macros: 111 CONST, VOLATILE, SIGNED, PROTO, EXFUN, DEFUN, DEFUN_VOID, 112 AND, DOTS, NOARGS. Don't use them. */ 113 114 #ifndef _ANSIDECL_H 115 #define _ANSIDECL_H 1 116 117 /* Every source file includes this file, 118 so they will all get the switch for lint. */ 119 /* LINTLIBRARY */ 120 121 /* Using MACRO(x,y) in cpp #if conditionals does not work with some 122 older preprocessors. Thus we can't define something like this: 123 124 #define HAVE_GCC_VERSION(MAJOR, MINOR) \ 125 (__GNUC__ > (MAJOR) || (__GNUC__ == (MAJOR) && __GNUC_MINOR__ >= (MINOR))) 126 127 and then test "#if HAVE_GCC_VERSION(2,7)". 128 129 So instead we use the macro below and test it against specific values. */ 130 131 /* This macro simplifies testing whether we are using gcc, and if it 132 is of a particular minimum version. (Both major & minor numbers are 133 significant.) This macro will evaluate to 0 if we are not using 134 gcc at all. */ 135 #ifndef GCC_VERSION 136 #define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__) 137 #endif /* GCC_VERSION */ 138 139 #if defined (__STDC__) || defined (_AIX) || (defined (__mips) && defined (_SYSTYPE_SVR4)) || defined(_WIN32) || (defined(__alpha) && defined(__cplusplus)) 140 /* All known AIX compilers implement these things (but don't always 141 define __STDC__). The RISC/OS MIPS compiler defines these things 142 in SVR4 mode, but does not define __STDC__. */ 143 /* eraxxon (at) alumni.rice.edu: The Compaq C++ compiler, unlike many other 144 C++ compilers, does not define __STDC__, though it acts as if this 145 was so. (Verified versions: 5.7, 6.2, 6.3, 6.5) */ 146 147 #define ANSI_PROTOTYPES 1 148 #define PTR void * 149 #define PTRCONST void *const 150 #define LONG_DOUBLE long double 151 152 /* PARAMS is often defined elsewhere (e.g. by libintl.h), so wrap it in 153 a #ifndef. */ 154 #ifndef PARAMS 155 #define PARAMS(ARGS) ARGS 156 #endif 157 158 #define VPARAMS(ARGS) ARGS 159 #define VA_START(VA_LIST, VAR) va_start(VA_LIST, VAR) 160 161 /* variadic function helper macros */ 162 /* "struct Qdmy" swallows the semicolon after VA_OPEN/VA_FIXEDARG's 163 use without inhibiting further decls and without declaring an 164 actual variable. */ 165 #define VA_OPEN(AP, VAR) { va_list AP; va_start(AP, VAR); { struct Qdmy 166 #define VA_CLOSE(AP) } va_end(AP); } 167 #define VA_FIXEDARG(AP, T, N) struct Qdmy 168 169 #undef const 170 #undef volatile 171 #undef signed 172 173 /* inline requires special treatment; it's in C99, and GCC >=2.7 supports 174 it too, but it's not in C89. */ 175 #undef inline 176 #if __STDC_VERSION__ > 199901L 177 /* it's a keyword */ 178 #else 179 # if GCC_VERSION >= 2007 180 # define inline __inline__ /* __inline__ prevents -pedantic warnings */ 181 # else 182 # define inline /* nothing */ 183 # endif 184 #endif 185 186 /* These are obsolete. Do not use. */ 187 #ifndef IN_GCC 188 #define CONST const 189 #define VOLATILE volatile 190 #define SIGNED signed 191 192 #define PROTO(type, name, arglist) type name arglist 193 #define EXFUN(name, proto) name proto 194 #define DEFUN(name, arglist, args) name(args) 195 #define DEFUN_VOID(name) name(void) 196 #define AND , 197 #define DOTS , ... 198 #define NOARGS void 199 #endif /* ! IN_GCC */ 200 201 #else /* Not ANSI C. */ 202 203 #undef ANSI_PROTOTYPES 204 #define PTR char * 205 #define PTRCONST PTR 206 #define LONG_DOUBLE double 207 208 #define PARAMS(args) () 209 #define VPARAMS(args) (va_alist) va_dcl 210 #define VA_START(va_list, var) va_start(va_list) 211 212 #define VA_OPEN(AP, VAR) { va_list AP; va_start(AP); { struct Qdmy 213 #define VA_CLOSE(AP) } va_end(AP); } 214 #define VA_FIXEDARG(AP, TYPE, NAME) TYPE NAME = va_arg(AP, TYPE) 215 216 /* some systems define these in header files for non-ansi mode */ 217 #undef const 218 #undef volatile 219 #undef signed 220 #undef inline 221 #define const 222 #define volatile 223 #define signed 224 #define inline 225 226 #ifndef IN_GCC 227 #define CONST 228 #define VOLATILE 229 #define SIGNED 230 231 #define PROTO(type, name, arglist) type name () 232 #define EXFUN(name, proto) name() 233 #define DEFUN(name, arglist, args) name arglist args; 234 #define DEFUN_VOID(name) name() 235 #define AND ; 236 #define DOTS 237 #define NOARGS 238 #endif /* ! IN_GCC */ 239 240 #endif /* ANSI C. */ 241 242 /* Define macros for some gcc attributes. This permits us to use the 243 macros freely, and know that they will come into play for the 244 version of gcc in which they are supported. */ 245 246 #if (GCC_VERSION < 2007) 247 # define __attribute__(x) 248 #endif 249 250 /* Attribute __malloc__ on functions was valid as of gcc 2.96. */ 251 #ifndef ATTRIBUTE_MALLOC 252 # if (GCC_VERSION >= 2096) 253 # define ATTRIBUTE_MALLOC __attribute__ ((__malloc__)) 254 # else 255 # define ATTRIBUTE_MALLOC 256 # endif /* GNUC >= 2.96 */ 257 #endif /* ATTRIBUTE_MALLOC */ 258 259 /* Attributes on labels were valid as of gcc 2.93. */ 260 #ifndef ATTRIBUTE_UNUSED_LABEL 261 # if (!defined (__cplusplus) && GCC_VERSION >= 2093) 262 # define ATTRIBUTE_UNUSED_LABEL ATTRIBUTE_UNUSED 263 # else 264 # define ATTRIBUTE_UNUSED_LABEL 265 # endif /* !__cplusplus && GNUC >= 2.93 */ 266 #endif /* ATTRIBUTE_UNUSED_LABEL */ 267 268 #ifndef ATTRIBUTE_UNUSED 269 #define ATTRIBUTE_UNUSED __attribute__ ((__unused__)) 270 #endif /* ATTRIBUTE_UNUSED */ 271 272 /* Before GCC 3.4, the C++ frontend couldn't parse attributes placed after the 273 identifier name. */ 274 #if ! defined(__cplusplus) || (GCC_VERSION >= 3004) 275 # define ARG_UNUSED(NAME) NAME ATTRIBUTE_UNUSED 276 #else /* !__cplusplus || GNUC >= 3.4 */ 277 # define ARG_UNUSED(NAME) NAME 278 #endif /* !__cplusplus || GNUC >= 3.4 */ 279 280 #ifndef ATTRIBUTE_NORETURN 281 #define ATTRIBUTE_NORETURN __attribute__ ((__noreturn__)) 282 #endif /* ATTRIBUTE_NORETURN */ 283 284 /* Attribute `nonnull' was valid as of gcc 3.3. */ 285 #ifndef ATTRIBUTE_NONNULL 286 # if (GCC_VERSION >= 3003) 287 # define ATTRIBUTE_NONNULL(m) __attribute__ ((__nonnull__ (m))) 288 # else 289 # define ATTRIBUTE_NONNULL(m) 290 # endif /* GNUC >= 3.3 */ 291 #endif /* ATTRIBUTE_NONNULL */ 292 293 /* Attribute `pure' was valid as of gcc 3.0. */ 294 #ifndef ATTRIBUTE_PURE 295 # if (GCC_VERSION >= 3000) 296 # define ATTRIBUTE_PURE __attribute__ ((__pure__)) 297 # else 298 # define ATTRIBUTE_PURE 299 # endif /* GNUC >= 3.0 */ 300 #endif /* ATTRIBUTE_PURE */ 301 302 /* Use ATTRIBUTE_PRINTF when the format specifier must not be NULL. 303 This was the case for the `printf' format attribute by itself 304 before GCC 3.3, but as of 3.3 we need to add the `nonnull' 305 attribute to retain this behavior. */ 306 #ifndef ATTRIBUTE_PRINTF 307 #define ATTRIBUTE_PRINTF(m, n) __attribute__ ((__format__ (__printf__, m, n))) ATTRIBUTE_NONNULL(m) 308 #define ATTRIBUTE_PRINTF_1 ATTRIBUTE_PRINTF(1, 2) 309 #define ATTRIBUTE_PRINTF_2 ATTRIBUTE_PRINTF(2, 3) 310 #define ATTRIBUTE_PRINTF_3 ATTRIBUTE_PRINTF(3, 4) 311 #define ATTRIBUTE_PRINTF_4 ATTRIBUTE_PRINTF(4, 5) 312 #define ATTRIBUTE_PRINTF_5 ATTRIBUTE_PRINTF(5, 6) 313 #endif /* ATTRIBUTE_PRINTF */ 314 315 /* Use ATTRIBUTE_FPTR_PRINTF when the format attribute is to be set on 316 a function pointer. Format attributes were allowed on function 317 pointers as of gcc 3.1. */ 318 #ifndef ATTRIBUTE_FPTR_PRINTF 319 # if (GCC_VERSION >= 3001) 320 # define ATTRIBUTE_FPTR_PRINTF(m, n) ATTRIBUTE_PRINTF(m, n) 321 # else 322 # define ATTRIBUTE_FPTR_PRINTF(m, n) 323 # endif /* GNUC >= 3.1 */ 324 # define ATTRIBUTE_FPTR_PRINTF_1 ATTRIBUTE_FPTR_PRINTF(1, 2) 325 # define ATTRIBUTE_FPTR_PRINTF_2 ATTRIBUTE_FPTR_PRINTF(2, 3) 326 # define ATTRIBUTE_FPTR_PRINTF_3 ATTRIBUTE_FPTR_PRINTF(3, 4) 327 # define ATTRIBUTE_FPTR_PRINTF_4 ATTRIBUTE_FPTR_PRINTF(4, 5) 328 # define ATTRIBUTE_FPTR_PRINTF_5 ATTRIBUTE_FPTR_PRINTF(5, 6) 329 #endif /* ATTRIBUTE_FPTR_PRINTF */ 330 331 /* Use ATTRIBUTE_NULL_PRINTF when the format specifier may be NULL. A 332 NULL format specifier was allowed as of gcc 3.3. */ 333 #ifndef ATTRIBUTE_NULL_PRINTF 334 # if (GCC_VERSION >= 3003) 335 # define ATTRIBUTE_NULL_PRINTF(m, n) __attribute__ ((__format__ (__printf__, m, n))) 336 # else 337 # define ATTRIBUTE_NULL_PRINTF(m, n) 338 # endif /* GNUC >= 3.3 */ 339 # define ATTRIBUTE_NULL_PRINTF_1 ATTRIBUTE_NULL_PRINTF(1, 2) 340 # define ATTRIBUTE_NULL_PRINTF_2 ATTRIBUTE_NULL_PRINTF(2, 3) 341 # define ATTRIBUTE_NULL_PRINTF_3 ATTRIBUTE_NULL_PRINTF(3, 4) 342 # define ATTRIBUTE_NULL_PRINTF_4 ATTRIBUTE_NULL_PRINTF(4, 5) 343 # define ATTRIBUTE_NULL_PRINTF_5 ATTRIBUTE_NULL_PRINTF(5, 6) 344 #endif /* ATTRIBUTE_NULL_PRINTF */ 345 346 /* Attribute `sentinel' was valid as of gcc 3.5. */ 347 #ifndef ATTRIBUTE_SENTINEL 348 # if (GCC_VERSION >= 3005) 349 # define ATTRIBUTE_SENTINEL __attribute__ ((__sentinel__)) 350 # else 351 # define ATTRIBUTE_SENTINEL 352 # endif /* GNUC >= 3.5 */ 353 #endif /* ATTRIBUTE_SENTINEL */ 354 355 356 #ifndef ATTRIBUTE_ALIGNED_ALIGNOF 357 # if (GCC_VERSION >= 3000) 358 # define ATTRIBUTE_ALIGNED_ALIGNOF(m) __attribute__ ((__aligned__ (__alignof__ (m)))) 359 # else 360 # define ATTRIBUTE_ALIGNED_ALIGNOF(m) 361 # endif /* GNUC >= 3.0 */ 362 #endif /* ATTRIBUTE_ALIGNED_ALIGNOF */ 363 364 /* Useful for structures whose layout must much some binary specification 365 regardless of the alignment and padding qualities of the compiler. */ 366 #ifndef ATTRIBUTE_PACKED 367 # define ATTRIBUTE_PACKED __attribute__ ((packed)) 368 #endif 369 370 /* Attribute `hot' and `cold' was valid as of gcc 4.3. */ 371 #ifndef ATTRIBUTE_COLD 372 # if (GCC_VERSION >= 4003) 373 # define ATTRIBUTE_COLD __attribute__ ((__cold__)) 374 # else 375 # define ATTRIBUTE_COLD 376 # endif /* GNUC >= 4.3 */ 377 #endif /* ATTRIBUTE_COLD */ 378 #ifndef ATTRIBUTE_HOT 379 # if (GCC_VERSION >= 4003) 380 # define ATTRIBUTE_HOT __attribute__ ((__hot__)) 381 # else 382 # define ATTRIBUTE_HOT 383 # endif /* GNUC >= 4.3 */ 384 #endif /* ATTRIBUTE_HOT */ 385 386 /* We use __extension__ in some places to suppress -pedantic warnings 387 about GCC extensions. This feature didn't work properly before 388 gcc 2.8. */ 389 #if GCC_VERSION < 2008 390 #define __extension__ 391 #endif 392 393 #endif /* ansidecl.h */ 394
