1 | /* Compiler compatibility macros |
2 | Copyright (C) 1991-2023 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | This program is free software; you can redistribute it and/or modify |
6 | it under the terms of the GNU General Public License as published by |
7 | the Free Software Foundation; either version 2 of the License, or |
8 | (at your option) any later version. |
9 | |
10 | This program is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
13 | GNU General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU General Public License |
16 | along with this program; if not, write to the Free Software |
17 | Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */ |
18 | |
19 | /* For ease of writing code which uses GCC extensions but needs to be |
20 | portable to other compilers, we provide the GCC_VERSION macro that |
21 | simplifies testing __GNUC__ and __GNUC_MINOR__ together, and various |
22 | wrappers around __attribute__. Also, __extension__ will be #defined |
23 | to nothing if it doesn't work. See below. */ |
24 | |
25 | #ifndef _ANSIDECL_H |
26 | #define _ANSIDECL_H 1 |
27 | |
28 | #ifdef __cplusplus |
29 | extern "C" { |
30 | #endif |
31 | |
32 | /* Every source file includes this file, |
33 | so they will all get the switch for lint. */ |
34 | /* LINTLIBRARY */ |
35 | |
36 | /* Using MACRO(x,y) in cpp #if conditionals does not work with some |
37 | older preprocessors. Thus we can't define something like this: |
38 | |
39 | #define HAVE_GCC_VERSION(MAJOR, MINOR) \ |
40 | (__GNUC__ > (MAJOR) || (__GNUC__ == (MAJOR) && __GNUC_MINOR__ >= (MINOR))) |
41 | |
42 | and then test "#if HAVE_GCC_VERSION(2,7)". |
43 | |
44 | So instead we use the macro below and test it against specific values. */ |
45 | |
46 | /* This macro simplifies testing whether we are using gcc, and if it |
47 | is of a particular minimum version. (Both major & minor numbers are |
48 | significant.) This macro will evaluate to 0 if we are not using |
49 | gcc at all. */ |
50 | #ifndef GCC_VERSION |
51 | #define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__) |
52 | #endif /* GCC_VERSION */ |
53 | |
54 | /* inline requires special treatment; it's in C99, and GCC >=2.7 supports |
55 | it too, but it's not in C89. */ |
56 | #undef inline |
57 | #if (!defined(__cplusplus) && __STDC_VERSION__ >= 199901L) || defined(__cplusplus) || (defined(__SUNPRO_C) && defined(__C99FEATURES__)) |
58 | /* it's a keyword */ |
59 | #else |
60 | # if GCC_VERSION >= 2007 |
61 | # define inline __inline__ /* __inline__ prevents -pedantic warnings */ |
62 | # else |
63 | # define inline /* nothing */ |
64 | # endif |
65 | #endif |
66 | |
67 | /* Define macros for some gcc attributes. This permits us to use the |
68 | macros freely, and know that they will come into play for the |
69 | version of gcc in which they are supported. */ |
70 | |
71 | #if (GCC_VERSION < 2007) |
72 | # define __attribute__(x) |
73 | #endif |
74 | |
75 | /* Attribute __malloc__ on functions was valid as of gcc 2.96. */ |
76 | #ifndef ATTRIBUTE_MALLOC |
77 | # if (GCC_VERSION >= 2096) |
78 | # define ATTRIBUTE_MALLOC __attribute__ ((__malloc__)) |
79 | # else |
80 | # define ATTRIBUTE_MALLOC |
81 | # endif /* GNUC >= 2.96 */ |
82 | #endif /* ATTRIBUTE_MALLOC */ |
83 | |
84 | /* Attributes on labels were valid as of gcc 2.93 and g++ 4.5. For |
85 | g++ an attribute on a label must be followed by a semicolon. */ |
86 | #ifndef ATTRIBUTE_UNUSED_LABEL |
87 | # ifndef __cplusplus |
88 | # if GCC_VERSION >= 2093 |
89 | # define ATTRIBUTE_UNUSED_LABEL ATTRIBUTE_UNUSED |
90 | # else |
91 | # define ATTRIBUTE_UNUSED_LABEL |
92 | # endif |
93 | # else |
94 | # if GCC_VERSION >= 4005 |
95 | # define ATTRIBUTE_UNUSED_LABEL ATTRIBUTE_UNUSED ; |
96 | # else |
97 | # define ATTRIBUTE_UNUSED_LABEL |
98 | # endif |
99 | # endif |
100 | #endif |
101 | |
102 | /* Similarly to ARG_UNUSED below. Prior to GCC 3.4, the C++ frontend |
103 | couldn't parse attributes placed after the identifier name, and now |
104 | the entire compiler is built with C++. */ |
105 | #ifndef ATTRIBUTE_UNUSED |
106 | #if GCC_VERSION >= 3004 |
107 | # define ATTRIBUTE_UNUSED __attribute__ ((__unused__)) |
108 | #else |
109 | #define ATTRIBUTE_UNUSED |
110 | #endif |
111 | #endif /* ATTRIBUTE_UNUSED */ |
112 | |
113 | /* Before GCC 3.4, the C++ frontend couldn't parse attributes placed after the |
114 | identifier name. */ |
115 | #if ! defined(__cplusplus) || (GCC_VERSION >= 3004) |
116 | # define ARG_UNUSED(NAME) NAME ATTRIBUTE_UNUSED |
117 | #else /* !__cplusplus || GNUC >= 3.4 */ |
118 | # define ARG_UNUSED(NAME) NAME |
119 | #endif /* !__cplusplus || GNUC >= 3.4 */ |
120 | |
121 | #ifndef ATTRIBUTE_NORETURN |
122 | #define ATTRIBUTE_NORETURN __attribute__ ((__noreturn__)) |
123 | #endif /* ATTRIBUTE_NORETURN */ |
124 | |
125 | /* Attribute `nonnull' was valid as of gcc 3.3. */ |
126 | #ifndef ATTRIBUTE_NONNULL |
127 | # if (GCC_VERSION >= 3003) |
128 | # define ATTRIBUTE_NONNULL(m) __attribute__ ((__nonnull__ (m))) |
129 | # else |
130 | # define ATTRIBUTE_NONNULL(m) |
131 | # endif /* GNUC >= 3.3 */ |
132 | #endif /* ATTRIBUTE_NONNULL */ |
133 | |
134 | /* Attribute `returns_nonnull' was valid as of gcc 4.9. */ |
135 | #ifndef ATTRIBUTE_RETURNS_NONNULL |
136 | # if (GCC_VERSION >= 4009) |
137 | # define ATTRIBUTE_RETURNS_NONNULL __attribute__ ((__returns_nonnull__)) |
138 | # else |
139 | # define ATTRIBUTE_RETURNS_NONNULL |
140 | # endif /* GNUC >= 4.9 */ |
141 | #endif /* ATTRIBUTE_RETURNS_NONNULL */ |
142 | |
143 | /* Attribute `pure' was valid as of gcc 3.0. */ |
144 | #ifndef ATTRIBUTE_PURE |
145 | # if (GCC_VERSION >= 3000) |
146 | # define ATTRIBUTE_PURE __attribute__ ((__pure__)) |
147 | # else |
148 | # define ATTRIBUTE_PURE |
149 | # endif /* GNUC >= 3.0 */ |
150 | #endif /* ATTRIBUTE_PURE */ |
151 | |
152 | /* Use ATTRIBUTE_PRINTF when the format specifier must not be NULL. |
153 | This was the case for the `printf' format attribute by itself |
154 | before GCC 3.3, but as of 3.3 we need to add the `nonnull' |
155 | attribute to retain this behavior. */ |
156 | #ifndef ATTRIBUTE_PRINTF |
157 | #define ATTRIBUTE_PRINTF(m, n) __attribute__ ((__format__ (__printf__, m, n))) ATTRIBUTE_NONNULL(m) |
158 | #define ATTRIBUTE_PRINTF_1 ATTRIBUTE_PRINTF(1, 2) |
159 | #define ATTRIBUTE_PRINTF_2 ATTRIBUTE_PRINTF(2, 3) |
160 | #define ATTRIBUTE_PRINTF_3 ATTRIBUTE_PRINTF(3, 4) |
161 | #define ATTRIBUTE_PRINTF_4 ATTRIBUTE_PRINTF(4, 5) |
162 | #define ATTRIBUTE_PRINTF_5 ATTRIBUTE_PRINTF(5, 6) |
163 | #endif /* ATTRIBUTE_PRINTF */ |
164 | |
165 | /* Use ATTRIBUTE_FPTR_PRINTF when the format attribute is to be set on |
166 | a function pointer. Format attributes were allowed on function |
167 | pointers as of gcc 3.1. */ |
168 | #ifndef ATTRIBUTE_FPTR_PRINTF |
169 | # if (GCC_VERSION >= 3001) |
170 | # define ATTRIBUTE_FPTR_PRINTF(m, n) ATTRIBUTE_PRINTF(m, n) |
171 | # else |
172 | # define ATTRIBUTE_FPTR_PRINTF(m, n) |
173 | # endif /* GNUC >= 3.1 */ |
174 | # define ATTRIBUTE_FPTR_PRINTF_1 ATTRIBUTE_FPTR_PRINTF(1, 2) |
175 | # define ATTRIBUTE_FPTR_PRINTF_2 ATTRIBUTE_FPTR_PRINTF(2, 3) |
176 | # define ATTRIBUTE_FPTR_PRINTF_3 ATTRIBUTE_FPTR_PRINTF(3, 4) |
177 | # define ATTRIBUTE_FPTR_PRINTF_4 ATTRIBUTE_FPTR_PRINTF(4, 5) |
178 | # define ATTRIBUTE_FPTR_PRINTF_5 ATTRIBUTE_FPTR_PRINTF(5, 6) |
179 | #endif /* ATTRIBUTE_FPTR_PRINTF */ |
180 | |
181 | /* Use ATTRIBUTE_NULL_PRINTF when the format specifier may be NULL. A |
182 | NULL format specifier was allowed as of gcc 3.3. */ |
183 | #ifndef ATTRIBUTE_NULL_PRINTF |
184 | # if (GCC_VERSION >= 3003) |
185 | # define ATTRIBUTE_NULL_PRINTF(m, n) __attribute__ ((__format__ (__printf__, m, n))) |
186 | # else |
187 | # define ATTRIBUTE_NULL_PRINTF(m, n) |
188 | # endif /* GNUC >= 3.3 */ |
189 | # define ATTRIBUTE_NULL_PRINTF_1 ATTRIBUTE_NULL_PRINTF(1, 2) |
190 | # define ATTRIBUTE_NULL_PRINTF_2 ATTRIBUTE_NULL_PRINTF(2, 3) |
191 | # define ATTRIBUTE_NULL_PRINTF_3 ATTRIBUTE_NULL_PRINTF(3, 4) |
192 | # define ATTRIBUTE_NULL_PRINTF_4 ATTRIBUTE_NULL_PRINTF(4, 5) |
193 | # define ATTRIBUTE_NULL_PRINTF_5 ATTRIBUTE_NULL_PRINTF(5, 6) |
194 | #endif /* ATTRIBUTE_NULL_PRINTF */ |
195 | |
196 | /* Attribute `sentinel' was valid as of gcc 3.5. */ |
197 | #ifndef ATTRIBUTE_SENTINEL |
198 | # if (GCC_VERSION >= 3005) |
199 | # define ATTRIBUTE_SENTINEL __attribute__ ((__sentinel__)) |
200 | # else |
201 | # define ATTRIBUTE_SENTINEL |
202 | # endif /* GNUC >= 3.5 */ |
203 | #endif /* ATTRIBUTE_SENTINEL */ |
204 | |
205 | |
206 | #ifndef ATTRIBUTE_ALIGNED_ALIGNOF |
207 | # if (GCC_VERSION >= 3000) |
208 | # define ATTRIBUTE_ALIGNED_ALIGNOF(m) __attribute__ ((__aligned__ (__alignof__ (m)))) |
209 | # else |
210 | # define ATTRIBUTE_ALIGNED_ALIGNOF(m) |
211 | # endif /* GNUC >= 3.0 */ |
212 | #endif /* ATTRIBUTE_ALIGNED_ALIGNOF */ |
213 | |
214 | /* Useful for structures whose layout must match some binary specification |
215 | regardless of the alignment and padding qualities of the compiler. */ |
216 | #ifndef ATTRIBUTE_PACKED |
217 | # define ATTRIBUTE_PACKED __attribute__ ((packed)) |
218 | #endif |
219 | |
220 | /* Attribute `hot' and `cold' was valid as of gcc 4.3. */ |
221 | #ifndef ATTRIBUTE_COLD |
222 | # if (GCC_VERSION >= 4003) |
223 | # define ATTRIBUTE_COLD __attribute__ ((__cold__)) |
224 | # else |
225 | # define ATTRIBUTE_COLD |
226 | # endif /* GNUC >= 4.3 */ |
227 | #endif /* ATTRIBUTE_COLD */ |
228 | #ifndef ATTRIBUTE_HOT |
229 | # if (GCC_VERSION >= 4003) |
230 | # define ATTRIBUTE_HOT __attribute__ ((__hot__)) |
231 | # else |
232 | # define ATTRIBUTE_HOT |
233 | # endif /* GNUC >= 4.3 */ |
234 | #endif /* ATTRIBUTE_HOT */ |
235 | |
236 | /* Attribute 'no_sanitize_undefined' was valid as of gcc 4.9. */ |
237 | #ifndef ATTRIBUTE_NO_SANITIZE_UNDEFINED |
238 | # if (GCC_VERSION >= 4009) |
239 | # define ATTRIBUTE_NO_SANITIZE_UNDEFINED __attribute__ ((no_sanitize_undefined)) |
240 | # else |
241 | # define ATTRIBUTE_NO_SANITIZE_UNDEFINED |
242 | # endif /* GNUC >= 4.9 */ |
243 | #endif /* ATTRIBUTE_NO_SANITIZE_UNDEFINED */ |
244 | |
245 | /* Attribute 'nonstring' was valid as of gcc 8. */ |
246 | #ifndef ATTRIBUTE_NONSTRING |
247 | # if GCC_VERSION >= 8000 |
248 | # define ATTRIBUTE_NONSTRING __attribute__ ((__nonstring__)) |
249 | # else |
250 | # define ATTRIBUTE_NONSTRING |
251 | # endif |
252 | #endif |
253 | |
254 | /* Attribute `alloc_size' was valid as of gcc 4.3. */ |
255 | #ifndef ATTRIBUTE_RESULT_SIZE_1 |
256 | # if (GCC_VERSION >= 4003) |
257 | # define ATTRIBUTE_RESULT_SIZE_1 __attribute__ ((alloc_size (1))) |
258 | # else |
259 | # define ATTRIBUTE_RESULT_SIZE_1 |
260 | #endif |
261 | #endif |
262 | |
263 | #ifndef ATTRIBUTE_RESULT_SIZE_2 |
264 | # if (GCC_VERSION >= 4003) |
265 | # define ATTRIBUTE_RESULT_SIZE_2 __attribute__ ((alloc_size (2))) |
266 | # else |
267 | # define ATTRIBUTE_RESULT_SIZE_2 |
268 | #endif |
269 | #endif |
270 | |
271 | #ifndef ATTRIBUTE_RESULT_SIZE_1_2 |
272 | # if (GCC_VERSION >= 4003) |
273 | # define ATTRIBUTE_RESULT_SIZE_1_2 __attribute__ ((alloc_size (1, 2))) |
274 | # else |
275 | # define ATTRIBUTE_RESULT_SIZE_1_2 |
276 | #endif |
277 | #endif |
278 | |
279 | /* Attribute `warn_unused_result' was valid as of gcc 3.3. */ |
280 | #ifndef ATTRIBUTE_WARN_UNUSED_RESULT |
281 | # if GCC_VERSION >= 3003 |
282 | # define ATTRIBUTE_WARN_UNUSED_RESULT __attribute__ ((__warn_unused_result__)) |
283 | # else |
284 | # define ATTRIBUTE_WARN_UNUSED_RESULT |
285 | # endif |
286 | #endif |
287 | |
288 | /* We use __extension__ in some places to suppress -pedantic warnings |
289 | about GCC extensions. This feature didn't work properly before |
290 | gcc 2.8. */ |
291 | #if GCC_VERSION < 2008 |
292 | #define __extension__ |
293 | #endif |
294 | |
295 | /* This is used to declare a const variable which should be visible |
296 | outside of the current compilation unit. Use it as |
297 | EXPORTED_CONST int i = 1; |
298 | This is because the semantics of const are different in C and C++. |
299 | "extern const" is permitted in C but it looks strange, and gcc |
300 | warns about it when -Wc++-compat is not used. */ |
301 | #ifdef __cplusplus |
302 | #define EXPORTED_CONST extern const |
303 | #else |
304 | #define EXPORTED_CONST const |
305 | #endif |
306 | |
307 | /* Be conservative and only use enum bitfields with C++ or GCC. |
308 | FIXME: provide a complete autoconf test for buggy enum bitfields. */ |
309 | |
310 | #ifdef __cplusplus |
311 | #define ENUM_BITFIELD(TYPE) enum TYPE |
312 | #elif (GCC_VERSION > 2000) |
313 | #define ENUM_BITFIELD(TYPE) __extension__ enum TYPE |
314 | #else |
315 | #define ENUM_BITFIELD(TYPE) unsigned int |
316 | #endif |
317 | |
318 | #if defined(__cplusplus) && __cpp_constexpr >= 200704 |
319 | #define CONSTEXPR constexpr |
320 | #else |
321 | #define CONSTEXPR |
322 | #endif |
323 | |
324 | /* A macro to disable the copy constructor and assignment operator. |
325 | When building with C++11 and above, the methods are explicitly |
326 | deleted, causing a compile-time error if something tries to copy. |
327 | For C++03, this just declares the methods, causing a link-time |
328 | error if the methods end up called (assuming you don't |
329 | define them). For C++03, for best results, place the macro |
330 | under the private: access specifier, like this, |
331 | |
332 | class name_lookup |
333 | { |
334 | private: |
335 | DISABLE_COPY_AND_ASSIGN (name_lookup); |
336 | }; |
337 | |
338 | so that most attempts at copy are caught at compile-time. */ |
339 | |
340 | #if defined(__cplusplus) && __cplusplus >= 201103 |
341 | #define DISABLE_COPY_AND_ASSIGN(TYPE) \ |
342 | TYPE (const TYPE&) = delete; \ |
343 | void operator= (const TYPE &) = delete |
344 | #else |
345 | #define DISABLE_COPY_AND_ASSIGN(TYPE) \ |
346 | TYPE (const TYPE&); \ |
347 | void operator= (const TYPE &) |
348 | #endif /* __cplusplus >= 201103 */ |
349 | |
350 | #ifdef __cplusplus |
351 | } |
352 | #endif |
353 | |
354 | #endif /* ansidecl.h */ |
355 | |