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[binutils.git] / include / ansidecl.h
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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.
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.
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.
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. */
20 /* ANSI and traditional C compatibility macros
22 ANSI C is assumed if __STDC__ is #defined.
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)
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.
38 For declaring functions with prototypes, we also provide these:
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:
45 char *strcpy PARAMS ((char *dest, char *source));
46 ...
47 char *
48 strcpy (dest, source)
49 char *dest;
50 char *source;
51 { ... }
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:
58 int printf PARAMS ((const char *format, ...));
59 ...
60 int
61 printf VPARAMS ((const char *format, ...))
63 ...
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.
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.
78 Here is a complete example:
80 int
81 printf VPARAMS ((const char *format, ...))
83 int result;
85 VA_OPEN (ap, format);
86 VA_FIXEDARG (ap, const char *, format);
88 result = vfprintf (stdout, format, ap);
89 VA_CLOSE (ap);
91 return result;
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.
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.
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. */
114 #ifndef _ANSIDECL_H
115 #define _ANSIDECL_H 1
117 /* Every source file includes this file,
118 so they will all get the switch for lint. */
119 /* LINTLIBRARY */
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:
124 #define HAVE_GCC_VERSION(MAJOR, MINOR) \
125 (__GNUC__ > (MAJOR) || (__GNUC__ == (MAJOR) && __GNUC_MINOR__ >= (MINOR)))
127 and then test "#if HAVE_GCC_VERSION(2,7)".
129 So instead we use the macro below and test it against specific values. */
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 */
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@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) */
147 #define ANSI_PROTOTYPES 1
148 #define PTR void *
149 #define PTRCONST void *const
150 #define LONG_DOUBLE long double
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
158 #define VPARAMS(ARGS) ARGS
159 #define VA_START(VA_LIST, VAR) va_start(VA_LIST, VAR)
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
169 #undef const
170 #undef volatile
171 #undef signed
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
186 /* These are obsolete. Do not use. */
187 #ifndef IN_GCC
188 #define CONST const
189 #define VOLATILE volatile
190 #define SIGNED signed
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 */
201 #else /* Not ANSI C. */
203 #undef ANSI_PROTOTYPES
204 #define PTR char *
205 #define PTRCONST PTR
206 #define LONG_DOUBLE double
208 #define PARAMS(args) ()
209 #define VPARAMS(args) (va_alist) va_dcl
210 #define VA_START(va_list, var) va_start(va_list)
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)
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
226 #ifndef IN_GCC
227 #define CONST
228 #define VOLATILE
229 #define SIGNED
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 */
240 #endif /* ANSI C. */
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. */
246 #if (GCC_VERSION < 2007)
247 # define __attribute__(x)
248 #endif
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 */
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 */
268 #ifndef ATTRIBUTE_UNUSED
269 #define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
270 #endif /* ATTRIBUTE_UNUSED */
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 */
280 #ifndef ATTRIBUTE_NORETURN
281 #define ATTRIBUTE_NORETURN __attribute__ ((__noreturn__))
282 #endif /* ATTRIBUTE_NORETURN */
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 */
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 */
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 */
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 */
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 */
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 */
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 */
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
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 */
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
393 #endif /* ansidecl.h */