ansidecl.h revision 1.6 1 1.1 christos /* ANSI and traditional C compatability macros
2 1.6 christos Copyright (C) 1991-2016 Free Software Foundation, Inc.
3 1.1 christos This file is part of the GNU C Library.
4 1.1 christos
5 1.1 christos This program is free software; you can redistribute it and/or modify
6 1.1 christos it under the terms of the GNU General Public License as published by
7 1.1 christos the Free Software Foundation; either version 2 of the License, or
8 1.1 christos (at your option) any later version.
9 1.1 christos
10 1.1 christos This program is distributed in the hope that it will be useful,
11 1.1 christos but WITHOUT ANY WARRANTY; without even the implied warranty of
12 1.1 christos MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 1.1 christos GNU General Public License for more details.
14 1.1 christos
15 1.1 christos You should have received a copy of the GNU General Public License
16 1.1 christos along with this program; if not, write to the Free Software
17 1.1 christos Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
18 1.1 christos
19 1.1 christos /* ANSI and traditional C compatibility macros
20 1.1 christos
21 1.1 christos ANSI C is assumed if __STDC__ is #defined.
22 1.1 christos
23 1.1 christos Macro ANSI C definition Traditional C definition
24 1.1 christos ----- ---- - ---------- ----------- - ----------
25 1.1 christos PTR `void *' `char *'
26 1.1 christos const not defined `'
27 1.1 christos volatile not defined `'
28 1.1 christos signed not defined `'
29 1.1 christos
30 1.1 christos For ease of writing code which uses GCC extensions but needs to be
31 1.1 christos portable to other compilers, we provide the GCC_VERSION macro that
32 1.1 christos simplifies testing __GNUC__ and __GNUC_MINOR__ together, and various
33 1.1 christos wrappers around __attribute__. Also, __extension__ will be #defined
34 1.3 christos to nothing if it doesn't work. See below. */
35 1.1 christos
36 1.1 christos #ifndef _ANSIDECL_H
37 1.1 christos #define _ANSIDECL_H 1
38 1.1 christos
39 1.1 christos #ifdef __cplusplus
40 1.1 christos extern "C" {
41 1.1 christos #endif
42 1.1 christos
43 1.1 christos /* Every source file includes this file,
44 1.1 christos so they will all get the switch for lint. */
45 1.1 christos /* LINTLIBRARY */
46 1.1 christos
47 1.1 christos /* Using MACRO(x,y) in cpp #if conditionals does not work with some
48 1.1 christos older preprocessors. Thus we can't define something like this:
49 1.1 christos
50 1.1 christos #define HAVE_GCC_VERSION(MAJOR, MINOR) \
51 1.1 christos (__GNUC__ > (MAJOR) || (__GNUC__ == (MAJOR) && __GNUC_MINOR__ >= (MINOR)))
52 1.1 christos
53 1.1 christos and then test "#if HAVE_GCC_VERSION(2,7)".
54 1.1 christos
55 1.1 christos So instead we use the macro below and test it against specific values. */
56 1.1 christos
57 1.1 christos /* This macro simplifies testing whether we are using gcc, and if it
58 1.1 christos is of a particular minimum version. (Both major & minor numbers are
59 1.1 christos significant.) This macro will evaluate to 0 if we are not using
60 1.1 christos gcc at all. */
61 1.1 christos #ifndef GCC_VERSION
62 1.1 christos #define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__)
63 1.1 christos #endif /* GCC_VERSION */
64 1.1 christos
65 1.1 christos #if defined (__STDC__) || defined(__cplusplus) || defined (_AIX) || (defined (__mips) && defined (_SYSTYPE_SVR4)) || defined(_WIN32)
66 1.1 christos /* All known AIX compilers implement these things (but don't always
67 1.1 christos define __STDC__). The RISC/OS MIPS compiler defines these things
68 1.1 christos in SVR4 mode, but does not define __STDC__. */
69 1.1 christos /* eraxxon (at) alumni.rice.edu: The Compaq C++ compiler, unlike many other
70 1.1 christos C++ compilers, does not define __STDC__, though it acts as if this
71 1.1 christos was so. (Verified versions: 5.7, 6.2, 6.3, 6.5) */
72 1.1 christos
73 1.1 christos #define PTR void *
74 1.1 christos
75 1.1 christos #undef const
76 1.1 christos #undef volatile
77 1.1 christos #undef signed
78 1.1 christos
79 1.1 christos /* inline requires special treatment; it's in C99, and GCC >=2.7 supports
80 1.1 christos it too, but it's not in C89. */
81 1.1 christos #undef inline
82 1.1 christos #if __STDC_VERSION__ >= 199901L || defined(__cplusplus) || (defined(__SUNPRO_C) && defined(__C99FEATURES__))
83 1.1 christos /* it's a keyword */
84 1.1 christos #else
85 1.1 christos # if GCC_VERSION >= 2007
86 1.1 christos # define inline __inline__ /* __inline__ prevents -pedantic warnings */
87 1.1 christos # else
88 1.1 christos # define inline /* nothing */
89 1.1 christos # endif
90 1.1 christos #endif
91 1.1 christos
92 1.1 christos #else /* Not ANSI C. */
93 1.1 christos
94 1.1 christos #define PTR char *
95 1.1 christos
96 1.1 christos /* some systems define these in header files for non-ansi mode */
97 1.1 christos #undef const
98 1.1 christos #undef volatile
99 1.1 christos #undef signed
100 1.1 christos #undef inline
101 1.1 christos #define const
102 1.1 christos #define volatile
103 1.1 christos #define signed
104 1.1 christos #define inline
105 1.1 christos
106 1.1 christos #endif /* ANSI C. */
107 1.1 christos
108 1.1 christos /* Define macros for some gcc attributes. This permits us to use the
109 1.1 christos macros freely, and know that they will come into play for the
110 1.1 christos version of gcc in which they are supported. */
111 1.1 christos
112 1.1 christos #if (GCC_VERSION < 2007)
113 1.1 christos # define __attribute__(x)
114 1.1 christos #endif
115 1.1 christos
116 1.1 christos /* Attribute __malloc__ on functions was valid as of gcc 2.96. */
117 1.1 christos #ifndef ATTRIBUTE_MALLOC
118 1.1 christos # if (GCC_VERSION >= 2096)
119 1.1 christos # define ATTRIBUTE_MALLOC __attribute__ ((__malloc__))
120 1.1 christos # else
121 1.1 christos # define ATTRIBUTE_MALLOC
122 1.1 christos # endif /* GNUC >= 2.96 */
123 1.1 christos #endif /* ATTRIBUTE_MALLOC */
124 1.1 christos
125 1.1 christos /* Attributes on labels were valid as of gcc 2.93 and g++ 4.5. For
126 1.1 christos g++ an attribute on a label must be followed by a semicolon. */
127 1.1 christos #ifndef ATTRIBUTE_UNUSED_LABEL
128 1.1 christos # ifndef __cplusplus
129 1.1 christos # if GCC_VERSION >= 2093
130 1.1 christos # define ATTRIBUTE_UNUSED_LABEL ATTRIBUTE_UNUSED
131 1.1 christos # else
132 1.1 christos # define ATTRIBUTE_UNUSED_LABEL
133 1.1 christos # endif
134 1.1 christos # else
135 1.1 christos # if GCC_VERSION >= 4005
136 1.1 christos # define ATTRIBUTE_UNUSED_LABEL ATTRIBUTE_UNUSED ;
137 1.1 christos # else
138 1.1 christos # define ATTRIBUTE_UNUSED_LABEL
139 1.1 christos # endif
140 1.1 christos # endif
141 1.1 christos #endif
142 1.1 christos
143 1.1 christos /* Similarly to ARG_UNUSED below. Prior to GCC 3.4, the C++ frontend
144 1.1 christos couldn't parse attributes placed after the identifier name, and now
145 1.1 christos the entire compiler is built with C++. */
146 1.1 christos #ifndef ATTRIBUTE_UNUSED
147 1.1 christos #if GCC_VERSION >= 3004
148 1.1 christos # define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
149 1.1 christos #else
150 1.1 christos #define ATTRIBUTE_UNUSED
151 1.1 christos #endif
152 1.1 christos #endif /* ATTRIBUTE_UNUSED */
153 1.1 christos
154 1.1 christos /* Before GCC 3.4, the C++ frontend couldn't parse attributes placed after the
155 1.1 christos identifier name. */
156 1.1 christos #if ! defined(__cplusplus) || (GCC_VERSION >= 3004)
157 1.1 christos # define ARG_UNUSED(NAME) NAME ATTRIBUTE_UNUSED
158 1.1 christos #else /* !__cplusplus || GNUC >= 3.4 */
159 1.1 christos # define ARG_UNUSED(NAME) NAME
160 1.1 christos #endif /* !__cplusplus || GNUC >= 3.4 */
161 1.1 christos
162 1.1 christos #ifndef ATTRIBUTE_NORETURN
163 1.1 christos #define ATTRIBUTE_NORETURN __attribute__ ((__noreturn__))
164 1.1 christos #endif /* ATTRIBUTE_NORETURN */
165 1.1 christos
166 1.1 christos /* Attribute `nonnull' was valid as of gcc 3.3. */
167 1.1 christos #ifndef ATTRIBUTE_NONNULL
168 1.1 christos # if (GCC_VERSION >= 3003)
169 1.1 christos # define ATTRIBUTE_NONNULL(m) __attribute__ ((__nonnull__ (m)))
170 1.1 christos # else
171 1.1 christos # define ATTRIBUTE_NONNULL(m)
172 1.1 christos # endif /* GNUC >= 3.3 */
173 1.1 christos #endif /* ATTRIBUTE_NONNULL */
174 1.1 christos
175 1.1 christos /* Attribute `returns_nonnull' was valid as of gcc 4.9. */
176 1.1 christos #ifndef ATTRIBUTE_RETURNS_NONNULL
177 1.1 christos # if (GCC_VERSION >= 4009)
178 1.1 christos # define ATTRIBUTE_RETURNS_NONNULL __attribute__ ((__returns_nonnull__))
179 1.1 christos # else
180 1.1 christos # define ATTRIBUTE_RETURNS_NONNULL
181 1.1 christos # endif /* GNUC >= 4.9 */
182 1.1 christos #endif /* ATTRIBUTE_RETURNS_NONNULL */
183 1.1 christos
184 1.1 christos /* Attribute `pure' was valid as of gcc 3.0. */
185 1.1 christos #ifndef ATTRIBUTE_PURE
186 1.1 christos # if (GCC_VERSION >= 3000)
187 1.1 christos # define ATTRIBUTE_PURE __attribute__ ((__pure__))
188 1.1 christos # else
189 1.1 christos # define ATTRIBUTE_PURE
190 1.1 christos # endif /* GNUC >= 3.0 */
191 1.1 christos #endif /* ATTRIBUTE_PURE */
192 1.1 christos
193 1.1 christos /* Use ATTRIBUTE_PRINTF when the format specifier must not be NULL.
194 1.1 christos This was the case for the `printf' format attribute by itself
195 1.1 christos before GCC 3.3, but as of 3.3 we need to add the `nonnull'
196 1.1 christos attribute to retain this behavior. */
197 1.1 christos #ifndef ATTRIBUTE_PRINTF
198 1.1 christos #define ATTRIBUTE_PRINTF(m, n) __attribute__ ((__format__ (__printf__, m, n))) ATTRIBUTE_NONNULL(m)
199 1.1 christos #define ATTRIBUTE_PRINTF_1 ATTRIBUTE_PRINTF(1, 2)
200 1.1 christos #define ATTRIBUTE_PRINTF_2 ATTRIBUTE_PRINTF(2, 3)
201 1.1 christos #define ATTRIBUTE_PRINTF_3 ATTRIBUTE_PRINTF(3, 4)
202 1.1 christos #define ATTRIBUTE_PRINTF_4 ATTRIBUTE_PRINTF(4, 5)
203 1.1 christos #define ATTRIBUTE_PRINTF_5 ATTRIBUTE_PRINTF(5, 6)
204 1.1 christos #endif /* ATTRIBUTE_PRINTF */
205 1.1 christos
206 1.1 christos /* Use ATTRIBUTE_FPTR_PRINTF when the format attribute is to be set on
207 1.1 christos a function pointer. Format attributes were allowed on function
208 1.1 christos pointers as of gcc 3.1. */
209 1.1 christos #ifndef ATTRIBUTE_FPTR_PRINTF
210 1.1 christos # if (GCC_VERSION >= 3001)
211 1.1 christos # define ATTRIBUTE_FPTR_PRINTF(m, n) ATTRIBUTE_PRINTF(m, n)
212 1.1 christos # else
213 1.1 christos # define ATTRIBUTE_FPTR_PRINTF(m, n)
214 1.1 christos # endif /* GNUC >= 3.1 */
215 1.1 christos # define ATTRIBUTE_FPTR_PRINTF_1 ATTRIBUTE_FPTR_PRINTF(1, 2)
216 1.1 christos # define ATTRIBUTE_FPTR_PRINTF_2 ATTRIBUTE_FPTR_PRINTF(2, 3)
217 1.1 christos # define ATTRIBUTE_FPTR_PRINTF_3 ATTRIBUTE_FPTR_PRINTF(3, 4)
218 1.1 christos # define ATTRIBUTE_FPTR_PRINTF_4 ATTRIBUTE_FPTR_PRINTF(4, 5)
219 1.1 christos # define ATTRIBUTE_FPTR_PRINTF_5 ATTRIBUTE_FPTR_PRINTF(5, 6)
220 1.1 christos #endif /* ATTRIBUTE_FPTR_PRINTF */
221 1.1 christos
222 1.1 christos /* Use ATTRIBUTE_NULL_PRINTF when the format specifier may be NULL. A
223 1.1 christos NULL format specifier was allowed as of gcc 3.3. */
224 1.1 christos #ifndef ATTRIBUTE_NULL_PRINTF
225 1.1 christos # if (GCC_VERSION >= 3003)
226 1.1 christos # define ATTRIBUTE_NULL_PRINTF(m, n) __attribute__ ((__format__ (__printf__, m, n)))
227 1.1 christos # else
228 1.1 christos # define ATTRIBUTE_NULL_PRINTF(m, n)
229 1.1 christos # endif /* GNUC >= 3.3 */
230 1.1 christos # define ATTRIBUTE_NULL_PRINTF_1 ATTRIBUTE_NULL_PRINTF(1, 2)
231 1.1 christos # define ATTRIBUTE_NULL_PRINTF_2 ATTRIBUTE_NULL_PRINTF(2, 3)
232 1.1 christos # define ATTRIBUTE_NULL_PRINTF_3 ATTRIBUTE_NULL_PRINTF(3, 4)
233 1.1 christos # define ATTRIBUTE_NULL_PRINTF_4 ATTRIBUTE_NULL_PRINTF(4, 5)
234 1.1 christos # define ATTRIBUTE_NULL_PRINTF_5 ATTRIBUTE_NULL_PRINTF(5, 6)
235 1.1 christos #endif /* ATTRIBUTE_NULL_PRINTF */
236 1.1 christos
237 1.1 christos /* Attribute `sentinel' was valid as of gcc 3.5. */
238 1.1 christos #ifndef ATTRIBUTE_SENTINEL
239 1.1 christos # if (GCC_VERSION >= 3005)
240 1.1 christos # define ATTRIBUTE_SENTINEL __attribute__ ((__sentinel__))
241 1.1 christos # else
242 1.1 christos # define ATTRIBUTE_SENTINEL
243 1.1 christos # endif /* GNUC >= 3.5 */
244 1.1 christos #endif /* ATTRIBUTE_SENTINEL */
245 1.1 christos
246 1.1 christos
247 1.1 christos #ifndef ATTRIBUTE_ALIGNED_ALIGNOF
248 1.1 christos # if (GCC_VERSION >= 3000)
249 1.1 christos # define ATTRIBUTE_ALIGNED_ALIGNOF(m) __attribute__ ((__aligned__ (__alignof__ (m))))
250 1.1 christos # else
251 1.1 christos # define ATTRIBUTE_ALIGNED_ALIGNOF(m)
252 1.1 christos # endif /* GNUC >= 3.0 */
253 1.1 christos #endif /* ATTRIBUTE_ALIGNED_ALIGNOF */
254 1.1 christos
255 1.1 christos /* Useful for structures whose layout must much some binary specification
256 1.1 christos regardless of the alignment and padding qualities of the compiler. */
257 1.1 christos #ifndef ATTRIBUTE_PACKED
258 1.1 christos # define ATTRIBUTE_PACKED __attribute__ ((packed))
259 1.1 christos #endif
260 1.1 christos
261 1.1 christos /* Attribute `hot' and `cold' was valid as of gcc 4.3. */
262 1.1 christos #ifndef ATTRIBUTE_COLD
263 1.1 christos # if (GCC_VERSION >= 4003)
264 1.1 christos # define ATTRIBUTE_COLD __attribute__ ((__cold__))
265 1.1 christos # else
266 1.1 christos # define ATTRIBUTE_COLD
267 1.1 christos # endif /* GNUC >= 4.3 */
268 1.1 christos #endif /* ATTRIBUTE_COLD */
269 1.1 christos #ifndef ATTRIBUTE_HOT
270 1.1 christos # if (GCC_VERSION >= 4003)
271 1.1 christos # define ATTRIBUTE_HOT __attribute__ ((__hot__))
272 1.1 christos # else
273 1.1 christos # define ATTRIBUTE_HOT
274 1.1 christos # endif /* GNUC >= 4.3 */
275 1.1 christos #endif /* ATTRIBUTE_HOT */
276 1.1 christos
277 1.6 christos /* Attribute 'no_sanitize_undefined' was valid as of gcc 4.9. */
278 1.6 christos #ifndef ATTRIBUTE_NO_SANITIZE_UNDEFINED
279 1.6 christos # if (GCC_VERSION >= 4009)
280 1.6 christos # define ATTRIBUTE_NO_SANITIZE_UNDEFINED __attribute__ ((no_sanitize_undefined))
281 1.6 christos # else
282 1.6 christos # define ATTRIBUTE_NO_SANITIZE_UNDEFINED
283 1.6 christos # endif /* GNUC >= 4.9 */
284 1.6 christos #endif /* ATTRIBUTE_NO_SANITIZE_UNDEFINED */
285 1.6 christos
286 1.1 christos /* We use __extension__ in some places to suppress -pedantic warnings
287 1.1 christos about GCC extensions. This feature didn't work properly before
288 1.1 christos gcc 2.8. */
289 1.1 christos #if GCC_VERSION < 2008
290 1.1 christos #define __extension__
291 1.1 christos #endif
292 1.1 christos
293 1.1 christos /* This is used to declare a const variable which should be visible
294 1.1 christos outside of the current compilation unit. Use it as
295 1.1 christos EXPORTED_CONST int i = 1;
296 1.1 christos This is because the semantics of const are different in C and C++.
297 1.1 christos "extern const" is permitted in C but it looks strange, and gcc
298 1.1 christos warns about it when -Wc++-compat is not used. */
299 1.1 christos #ifdef __cplusplus
300 1.1 christos #define EXPORTED_CONST extern const
301 1.1 christos #else
302 1.1 christos #define EXPORTED_CONST const
303 1.1 christos #endif
304 1.1 christos
305 1.1 christos /* Be conservative and only use enum bitfields with C++ or GCC.
306 1.1 christos FIXME: provide a complete autoconf test for buggy enum bitfields. */
307 1.1 christos
308 1.1 christos #ifdef __cplusplus
309 1.1 christos #define ENUM_BITFIELD(TYPE) enum TYPE
310 1.1 christos #elif (GCC_VERSION > 2000)
311 1.1 christos #define ENUM_BITFIELD(TYPE) __extension__ enum TYPE
312 1.1 christos #else
313 1.1 christos #define ENUM_BITFIELD(TYPE) unsigned int
314 1.1 christos #endif
315 1.1 christos
316 1.6 christos /* This is used to mark a class or virtual function as final. */
317 1.6 christos #if __cplusplus >= 201103L
318 1.6 christos #define GCC_FINAL final
319 1.6 christos #elif GCC_VERSION >= 4007
320 1.6 christos #define GCC_FINAL __final
321 1.6 christos #else
322 1.6 christos #define GCC_FINAL
323 1.6 christos #endif
324 1.6 christos
325 1.1 christos #ifdef __cplusplus
326 1.1 christos }
327 1.1 christos #endif
328 1.1 christos
329 1.1 christos #endif /* ansidecl.h */
330