1
/* ANSI and traditional C compatability macros
2
Copyright 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
3
2002, 2003, 2004, 2005, 2006, 2007, 2009, 2010
4
Free Software Foundation, Inc.
5
This file is part of the GNU C Library.
7
This program is free software; you can redistribute it and/or modify
8
it under the terms of the GNU General Public License as published by
9
the Free Software Foundation; either version 2 of the License, or
10
(at your option) any later version.
12
This program is distributed in the hope that it will be useful,
13
but WITHOUT ANY WARRANTY; without even the implied warranty of
14
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15
GNU General Public License for more details.
17
You should have received a copy of the GNU General Public License
18
along with this program; if not, write to the Free Software
19
Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
21
/* ANSI and traditional C compatibility macros
23
ANSI C is assumed if __STDC__ is #defined.
25
Macro ANSI C definition Traditional C definition
26
----- ---- - ---------- ----------- - ----------
27
ANSI_PROTOTYPES 1 not defined
29
PTRCONST `void *const' `char *'
30
LONG_DOUBLE `long double' `double'
32
volatile not defined `'
34
VA_START(ap, var) va_start(ap, var) va_start(ap)
36
Note that it is safe to write "void foo();" indicating a function
37
with no return value, in all K+R compilers we have been able to test.
39
For declaring functions with prototypes, we also provide these:
42
-- for functions which take a fixed number of arguments. Use this
43
when declaring the function. When defining the function, write a
44
K+R style argument list. For example:
46
char *strcpy PARAMS ((char *dest, char *source));
55
VPARAMS ((prototype, ...))
56
-- for functions which take a variable number of arguments. Use
57
PARAMS to declare the function, VPARAMS to define it. For example:
59
int printf PARAMS ((const char *format, ...));
62
printf VPARAMS ((const char *format, ...))
67
For writing functions which take variable numbers of arguments, we
68
also provide the VA_OPEN, VA_CLOSE, and VA_FIXEDARG macros. These
69
hide the differences between K+R <varargs.h> and C89 <stdarg.h> more
70
thoroughly than the simple VA_START() macro mentioned above.
72
VA_OPEN and VA_CLOSE are used *instead of* va_start and va_end.
73
Immediately after VA_OPEN, put a sequence of VA_FIXEDARG calls
74
corresponding to the list of fixed arguments. Then use va_arg
75
normally to get the variable arguments, or pass your va_list object
76
around. You do not declare the va_list yourself; VA_OPEN does it
79
Here is a complete example:
82
printf VPARAMS ((const char *format, ...))
87
VA_FIXEDARG (ap, const char *, format);
89
result = vfprintf (stdout, format, ap);
96
You can declare variables either before or after the VA_OPEN,
97
VA_FIXEDARG sequence. Also, VA_OPEN and VA_CLOSE are the beginning
98
and end of a block. They must appear at the same nesting level,
99
and any variables declared after VA_OPEN go out of scope at
100
VA_CLOSE. Unfortunately, with a K+R compiler, that includes the
101
argument list. You can have multiple instances of VA_OPEN/VA_CLOSE
102
pairs in a single function in case you need to traverse the
103
argument list more than once.
105
For ease of writing code which uses GCC extensions but needs to be
106
portable to other compilers, we provide the GCC_VERSION macro that
107
simplifies testing __GNUC__ and __GNUC_MINOR__ together, and various
108
wrappers around __attribute__. Also, __extension__ will be #defined
109
to nothing if it doesn't work. See below.
111
This header also defines a lot of obsolete macros:
112
CONST, VOLATILE, SIGNED, PROTO, EXFUN, DEFUN, DEFUN_VOID,
113
AND, DOTS, NOARGS. Don't use them. */
116
#define _ANSIDECL_H 1
122
/* Every source file includes this file,
123
so they will all get the switch for lint. */
126
/* Using MACRO(x,y) in cpp #if conditionals does not work with some
127
older preprocessors. Thus we can't define something like this:
129
#define HAVE_GCC_VERSION(MAJOR, MINOR) \
130
(__GNUC__ > (MAJOR) || (__GNUC__ == (MAJOR) && __GNUC_MINOR__ >= (MINOR)))
132
and then test "#if HAVE_GCC_VERSION(2,7)".
134
So instead we use the macro below and test it against specific values. */
136
/* This macro simplifies testing whether we are using gcc, and if it
137
is of a particular minimum version. (Both major & minor numbers are
138
significant.) This macro will evaluate to 0 if we are not using
141
#define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__)
142
#endif /* GCC_VERSION */
144
#if defined (__STDC__) || defined(__cplusplus) || defined (_AIX) || (defined (__mips) && defined (_SYSTYPE_SVR4)) || defined(_WIN32)
145
/* All known AIX compilers implement these things (but don't always
146
define __STDC__). The RISC/OS MIPS compiler defines these things
147
in SVR4 mode, but does not define __STDC__. */
148
/* eraxxon@alumni.rice.edu: The Compaq C++ compiler, unlike many other
149
C++ compilers, does not define __STDC__, though it acts as if this
150
was so. (Verified versions: 5.7, 6.2, 6.3, 6.5) */
152
#define ANSI_PROTOTYPES 1
154
#define PTRCONST void *const
155
#define LONG_DOUBLE long double
157
/* PARAMS is often defined elsewhere (e.g. by libintl.h), so wrap it in
160
#define PARAMS(ARGS) ARGS
163
#define VPARAMS(ARGS) ARGS
164
#define VA_START(VA_LIST, VAR) va_start(VA_LIST, VAR)
166
/* variadic function helper macros */
167
/* "struct Qdmy" swallows the semicolon after VA_OPEN/VA_FIXEDARG's
168
use without inhibiting further decls and without declaring an
170
#define VA_OPEN(AP, VAR) { va_list AP; va_start(AP, VAR); { struct Qdmy
171
#define VA_CLOSE(AP) } va_end(AP); }
172
#define VA_FIXEDARG(AP, T, N) struct Qdmy
178
/* inline requires special treatment; it's in C99, and GCC >=2.7 supports
179
it too, but it's not in C89. */
181
#if __STDC_VERSION__ >= 199901L || defined(__cplusplus) || (defined(__SUNPRO_C) && defined(__C99FEATURES__))
184
# if GCC_VERSION >= 2007
185
# define inline __inline__ /* __inline__ prevents -pedantic warnings */
187
# define inline /* nothing */
191
/* These are obsolete. Do not use. */
194
#define VOLATILE volatile
195
#define SIGNED signed
197
#define PROTO(type, name, arglist) type name arglist
198
#define EXFUN(name, proto) name proto
199
#define DEFUN(name, arglist, args) name(args)
200
#define DEFUN_VOID(name) name(void)
204
#endif /* ! IN_GCC */
206
#else /* Not ANSI C. */
208
#undef ANSI_PROTOTYPES
211
#define LONG_DOUBLE double
213
#define PARAMS(args) ()
214
#define VPARAMS(args) (va_alist) va_dcl
215
#define VA_START(va_list, var) va_start(va_list)
217
#define VA_OPEN(AP, VAR) { va_list AP; va_start(AP); { struct Qdmy
218
#define VA_CLOSE(AP) } va_end(AP); }
219
#define VA_FIXEDARG(AP, TYPE, NAME) TYPE NAME = va_arg(AP, TYPE)
221
/* some systems define these in header files for non-ansi mode */
236
#define PROTO(type, name, arglist) type name ()
237
#define EXFUN(name, proto) name()
238
#define DEFUN(name, arglist, args) name arglist args;
239
#define DEFUN_VOID(name) name()
243
#endif /* ! IN_GCC */
247
/* Define macros for some gcc attributes. This permits us to use the
248
macros freely, and know that they will come into play for the
249
version of gcc in which they are supported. */
251
#if (GCC_VERSION < 2007)
252
# define __attribute__(x)
255
/* Attribute __malloc__ on functions was valid as of gcc 2.96. */
256
#ifndef ATTRIBUTE_MALLOC
257
# if (GCC_VERSION >= 2096)
258
# define ATTRIBUTE_MALLOC __attribute__ ((__malloc__))
260
# define ATTRIBUTE_MALLOC
261
# endif /* GNUC >= 2.96 */
262
#endif /* ATTRIBUTE_MALLOC */
264
/* Attributes on labels were valid as of gcc 2.93 and g++ 4.5. For
265
g++ an attribute on a label must be followed by a semicolon. */
266
#ifndef ATTRIBUTE_UNUSED_LABEL
268
# if GCC_VERSION >= 2093
269
# define ATTRIBUTE_UNUSED_LABEL ATTRIBUTE_UNUSED
271
# define ATTRIBUTE_UNUSED_LABEL
274
# if GCC_VERSION >= 4005
275
# define ATTRIBUTE_UNUSED_LABEL ATTRIBUTE_UNUSED ;
277
# define ATTRIBUTE_UNUSED_LABEL
282
/* Similarly to ARG_UNUSED below. Prior to GCC 3.4, the C++ frontend
283
couldn't parse attributes placed after the identifier name, and now
284
the entire compiler is built with C++. */
285
#ifndef ATTRIBUTE_UNUSED
286
#if GCC_VERSION >= 3004
287
# define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
289
#define ATTRIBUTE_UNUSED
291
#endif /* ATTRIBUTE_UNUSED */
293
/* Before GCC 3.4, the C++ frontend couldn't parse attributes placed after the
295
#if ! defined(__cplusplus) || (GCC_VERSION >= 3004)
296
# define ARG_UNUSED(NAME) NAME ATTRIBUTE_UNUSED
297
#else /* !__cplusplus || GNUC >= 3.4 */
298
# define ARG_UNUSED(NAME) NAME
299
#endif /* !__cplusplus || GNUC >= 3.4 */
301
#ifndef ATTRIBUTE_NORETURN
302
#define ATTRIBUTE_NORETURN __attribute__ ((__noreturn__))
303
#endif /* ATTRIBUTE_NORETURN */
305
/* Attribute `nonnull' was valid as of gcc 3.3. */
306
#ifndef ATTRIBUTE_NONNULL
307
# if (GCC_VERSION >= 3003)
308
# define ATTRIBUTE_NONNULL(m) __attribute__ ((__nonnull__ (m)))
310
# define ATTRIBUTE_NONNULL(m)
311
# endif /* GNUC >= 3.3 */
312
#endif /* ATTRIBUTE_NONNULL */
314
/* Attribute `pure' was valid as of gcc 3.0. */
315
#ifndef ATTRIBUTE_PURE
316
# if (GCC_VERSION >= 3000)
317
# define ATTRIBUTE_PURE __attribute__ ((__pure__))
319
# define ATTRIBUTE_PURE
320
# endif /* GNUC >= 3.0 */
321
#endif /* ATTRIBUTE_PURE */
323
/* Use ATTRIBUTE_PRINTF when the format specifier must not be NULL.
324
This was the case for the `printf' format attribute by itself
325
before GCC 3.3, but as of 3.3 we need to add the `nonnull'
326
attribute to retain this behavior. */
327
#ifndef ATTRIBUTE_PRINTF
328
#define ATTRIBUTE_PRINTF(m, n) __attribute__ ((__format__ (__printf__, m, n))) ATTRIBUTE_NONNULL(m)
329
#define ATTRIBUTE_PRINTF_1 ATTRIBUTE_PRINTF(1, 2)
330
#define ATTRIBUTE_PRINTF_2 ATTRIBUTE_PRINTF(2, 3)
331
#define ATTRIBUTE_PRINTF_3 ATTRIBUTE_PRINTF(3, 4)
332
#define ATTRIBUTE_PRINTF_4 ATTRIBUTE_PRINTF(4, 5)
333
#define ATTRIBUTE_PRINTF_5 ATTRIBUTE_PRINTF(5, 6)
334
#endif /* ATTRIBUTE_PRINTF */
336
/* Use ATTRIBUTE_FPTR_PRINTF when the format attribute is to be set on
337
a function pointer. Format attributes were allowed on function
338
pointers as of gcc 3.1. */
339
#ifndef ATTRIBUTE_FPTR_PRINTF
340
# if (GCC_VERSION >= 3001)
341
# define ATTRIBUTE_FPTR_PRINTF(m, n) ATTRIBUTE_PRINTF(m, n)
343
# define ATTRIBUTE_FPTR_PRINTF(m, n)
344
# endif /* GNUC >= 3.1 */
345
# define ATTRIBUTE_FPTR_PRINTF_1 ATTRIBUTE_FPTR_PRINTF(1, 2)
346
# define ATTRIBUTE_FPTR_PRINTF_2 ATTRIBUTE_FPTR_PRINTF(2, 3)
347
# define ATTRIBUTE_FPTR_PRINTF_3 ATTRIBUTE_FPTR_PRINTF(3, 4)
348
# define ATTRIBUTE_FPTR_PRINTF_4 ATTRIBUTE_FPTR_PRINTF(4, 5)
349
# define ATTRIBUTE_FPTR_PRINTF_5 ATTRIBUTE_FPTR_PRINTF(5, 6)
350
#endif /* ATTRIBUTE_FPTR_PRINTF */
352
/* Use ATTRIBUTE_NULL_PRINTF when the format specifier may be NULL. A
353
NULL format specifier was allowed as of gcc 3.3. */
354
#ifndef ATTRIBUTE_NULL_PRINTF
355
# if (GCC_VERSION >= 3003)
356
# define ATTRIBUTE_NULL_PRINTF(m, n) __attribute__ ((__format__ (__printf__, m, n)))
358
# define ATTRIBUTE_NULL_PRINTF(m, n)
359
# endif /* GNUC >= 3.3 */
360
# define ATTRIBUTE_NULL_PRINTF_1 ATTRIBUTE_NULL_PRINTF(1, 2)
361
# define ATTRIBUTE_NULL_PRINTF_2 ATTRIBUTE_NULL_PRINTF(2, 3)
362
# define ATTRIBUTE_NULL_PRINTF_3 ATTRIBUTE_NULL_PRINTF(3, 4)
363
# define ATTRIBUTE_NULL_PRINTF_4 ATTRIBUTE_NULL_PRINTF(4, 5)
364
# define ATTRIBUTE_NULL_PRINTF_5 ATTRIBUTE_NULL_PRINTF(5, 6)
365
#endif /* ATTRIBUTE_NULL_PRINTF */
367
/* Attribute `sentinel' was valid as of gcc 3.5. */
368
#ifndef ATTRIBUTE_SENTINEL
369
# if (GCC_VERSION >= 3005)
370
# define ATTRIBUTE_SENTINEL __attribute__ ((__sentinel__))
372
# define ATTRIBUTE_SENTINEL
373
# endif /* GNUC >= 3.5 */
374
#endif /* ATTRIBUTE_SENTINEL */
377
#ifndef ATTRIBUTE_ALIGNED_ALIGNOF
378
# if (GCC_VERSION >= 3000)
379
# define ATTRIBUTE_ALIGNED_ALIGNOF(m) __attribute__ ((__aligned__ (__alignof__ (m))))
381
# define ATTRIBUTE_ALIGNED_ALIGNOF(m)
382
# endif /* GNUC >= 3.0 */
383
#endif /* ATTRIBUTE_ALIGNED_ALIGNOF */
385
/* Useful for structures whose layout must much some binary specification
386
regardless of the alignment and padding qualities of the compiler. */
387
#ifndef ATTRIBUTE_PACKED
388
# define ATTRIBUTE_PACKED __attribute__ ((packed))
391
/* Attribute `hot' and `cold' was valid as of gcc 4.3. */
392
#ifndef ATTRIBUTE_COLD
393
# if (GCC_VERSION >= 4003)
394
# define ATTRIBUTE_COLD __attribute__ ((__cold__))
396
# define ATTRIBUTE_COLD
397
# endif /* GNUC >= 4.3 */
398
#endif /* ATTRIBUTE_COLD */
399
#ifndef ATTRIBUTE_HOT
400
# if (GCC_VERSION >= 4003)
401
# define ATTRIBUTE_HOT __attribute__ ((__hot__))
403
# define ATTRIBUTE_HOT
404
# endif /* GNUC >= 4.3 */
405
#endif /* ATTRIBUTE_HOT */
407
/* We use __extension__ in some places to suppress -pedantic warnings
408
about GCC extensions. This feature didn't work properly before
410
#if GCC_VERSION < 2008
411
#define __extension__
414
/* This is used to declare a const variable which should be visible
415
outside of the current compilation unit. Use it as
416
EXPORTED_CONST int i = 1;
417
This is because the semantics of const are different in C and C++.
418
"extern const" is permitted in C but it looks strange, and gcc
419
warns about it when -Wc++-compat is not used. */
421
#define EXPORTED_CONST extern const
423
#define EXPORTED_CONST const
426
/* Be conservative and only use enum bitfields with C++ or GCC.
427
FIXME: provide a complete autoconf test for buggy enum bitfields. */
430
#define ENUM_BITFIELD(TYPE) enum TYPE
431
#elif (GCC_VERSION > 2000)
432
#define ENUM_BITFIELD(TYPE) __extension__ enum TYPE
434
#define ENUM_BITFIELD(TYPE) unsigned int
441
#endif /* ansidecl.h */