binutils (2.41)
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 */
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