Commit f256f11d80b7fb302df2433e8613dd7bb50ba20b

Add missing attributes.m4 macro file.
m4/attributes.m4
(311 / 0)
  
1dnl Macros to check the presence of generic (non-typed) symbols.
2dnl Copyright (c) 2006-2008 Diego Pettenò <flameeyes@gmail.com>
3dnl Copyright (c) 2006-2008 xine project
4dnl
5dnl This program is free software; you can redistribute it and/or modify
6dnl it under the terms of the GNU General Public License as published by
7dnl the Free Software Foundation; either version 2, or (at your option)
8dnl any later version.
9dnl
10dnl This program is distributed in the hope that it will be useful,
11dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
12dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13dnl GNU General Public License for more details.
14dnl
15dnl You should have received a copy of the GNU General Public License
16dnl along with this program; if not, write to the Free Software
17dnl Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
18dnl 02110-1301, USA.
19dnl
20dnl As a special exception, the copyright owners of the
21dnl macro gives unlimited permission to copy, distribute and modify the
22dnl configure scripts that are the output of Autoconf when processing the
23dnl Macro. You need not follow the terms of the GNU General Public
24dnl License when using or distributing such scripts, even though portions
25dnl of the text of the Macro appear in them. The GNU General Public
26dnl License (GPL) does govern all other use of the material that
27dnl constitutes the Autoconf Macro.
28dnl
29dnl This special exception to the GPL applies to versions of the
30dnl Autoconf Macro released by this project. When you make and
31dnl distribute a modified version of the Autoconf Macro, you may extend
32dnl this special exception to the GPL to apply to your modified version as
33dnl well.
34
35dnl Check if the flag is supported by compiler
36dnl CC_CHECK_CFLAGS_SILENT([FLAG], [ACTION-IF-FOUND],[ACTION-IF-NOT-FOUND])
37
38AC_DEFUN([CC_CHECK_CFLAGS_SILENT], [
39 AC_CACHE_VAL(AS_TR_SH([cc_cv_cflags_$1]),
40 [ac_save_CFLAGS="$CFLAGS"
41 CFLAGS="$CFLAGS $1"
42 AC_COMPILE_IFELSE([int a;],
43 [eval "AS_TR_SH([cc_cv_cflags_$1])='yes'"],
44 [eval "AS_TR_SH([cc_cv_cflags_$1])='no'"])
45 CFLAGS="$ac_save_CFLAGS"
46 ])
47
48 AS_IF([eval test x$]AS_TR_SH([cc_cv_cflags_$1])[ = xyes],
49 [$2], [$3])
50])
51
52dnl Check if the flag is supported by compiler (cacheable)
53dnl CC_CHECK_CFLAGS([FLAG], [ACTION-IF-FOUND],[ACTION-IF-NOT-FOUND])
54
55AC_DEFUN([CC_CHECK_CFLAGS], [
56 AC_CACHE_CHECK([if $CC supports $1 flag],
57 AS_TR_SH([cc_cv_cflags_$1]),
58 CC_CHECK_CFLAGS_SILENT([$1]) dnl Don't execute actions here!
59 )
60
61 AS_IF([eval test x$]AS_TR_SH([cc_cv_cflags_$1])[ = xyes],
62 [$2], [$3])
63])
64
65dnl CC_CHECK_CFLAG_APPEND(FLAG, [action-if-found], [action-if-not-found])
66dnl Check for CFLAG and appends them to CFLAGS if supported
67AC_DEFUN([CC_CHECK_CFLAG_APPEND], [
68 AC_CACHE_CHECK([if $CC supports $1 flag],
69 AS_TR_SH([cc_cv_cflags_$1]),
70 CC_CHECK_CFLAGS_SILENT([$1]) dnl Don't execute actions here!
71 )
72
73 AS_IF([eval test x$]AS_TR_SH([cc_cv_cflags_$1])[ = xyes],
74 [CFLAGS="$CFLAGS $1"; DEBUG_CFLAGS="$DEBUG_CFLAGS $1"; $2], [$3])
75])
76
77dnl CC_CHECK_CFLAGS_APPEND([FLAG1 FLAG2], [action-if-found], [action-if-not])
78AC_DEFUN([CC_CHECK_CFLAGS_APPEND], [
79 for flag in $1; do
80 CC_CHECK_CFLAG_APPEND($flag, [$2], [$3])
81 done
82])
83
84dnl Check if the flag is supported by linker (cacheable)
85dnl CC_CHECK_LDFLAGS([FLAG], [ACTION-IF-FOUND],[ACTION-IF-NOT-FOUND])
86
87AC_DEFUN([CC_CHECK_LDFLAGS], [
88 AC_CACHE_CHECK([if $CC supports $1 flag],
89 AS_TR_SH([cc_cv_ldflags_$1]),
90 [ac_save_LDFLAGS="$LDFLAGS"
91 LDFLAGS="$LDFLAGS $1"
92 AC_LINK_IFELSE([int main() { return 1; }],
93 [eval "AS_TR_SH([cc_cv_ldflags_$1])='yes'"],
94 [eval "AS_TR_SH([cc_cv_ldflags_$1])="])
95 LDFLAGS="$ac_save_LDFLAGS"
96 ])
97
98 AS_IF([eval test x$]AS_TR_SH([cc_cv_ldflags_$1])[ = xyes],
99 [$2], [$3])
100])
101
102dnl define the LDFLAGS_NOUNDEFINED variable with the correct value for
103dnl the current linker to avoid undefined references in a shared object.
104AC_DEFUN([CC_NOUNDEFINED], [
105 dnl We check $host for which systems to enable this for.
106 AC_REQUIRE([AC_CANONICAL_HOST])
107
108 case $host in
109 dnl FreeBSD (et al.) does not complete linking for shared objects when pthreads
110 dnl are requested, as different implementations are present; to avoid problems
111 dnl use -Wl,-z,defs only for those platform not behaving this way.
112 *-freebsd* | *-openbsd*) ;;
113 *)
114 dnl First of all check for the --no-undefined variant of GNU ld. This allows
115 dnl for a much more readable commandline, so that people can understand what
116 dnl it does without going to look for what the heck -z defs does.
117 for possible_flags in "-Wl,--no-undefined" "-Wl,-z,defs"; do
118 CC_CHECK_LDFLAGS([$possible_flags], [LDFLAGS_NOUNDEFINED="$possible_flags"])
119 break
120 done
121 ;;
122 esac
123
124 AC_SUBST([LDFLAGS_NOUNDEFINED])
125])
126
127dnl Check for a -Werror flag or equivalent. -Werror is the GCC
128dnl and ICC flag that tells the compiler to treat all the warnings
129dnl as fatal. We usually need this option to make sure that some
130dnl constructs (like attributes) are not simply ignored.
131dnl
132dnl Other compilers don't support -Werror per se, but they support
133dnl an equivalent flag:
134dnl - Sun Studio compiler supports -errwarn=%all
135AC_DEFUN([CC_CHECK_WERROR], [
136 AC_CACHE_CHECK(
137 [for $CC way to treat warnings as errors],
138 [cc_cv_werror],
139 [CC_CHECK_CFLAGS_SILENT([-Werror], [cc_cv_werror=-Werror],
140 [CC_CHECK_CFLAGS_SILENT([-errwarn=%all], [cc_cv_werror=-errwarn=%all])])
141 ])
142])
143
144AC_DEFUN([CC_CHECK_ATTRIBUTE], [
145 AC_REQUIRE([CC_CHECK_WERROR])
146 AC_CACHE_CHECK([if $CC supports __attribute__(( ifelse([$2], , [$1], [$2]) ))],
147 AS_TR_SH([cc_cv_attribute_$1]),
148 [ac_save_CFLAGS="$CFLAGS"
149 CFLAGS="$CFLAGS $cc_cv_werror"
150 AC_COMPILE_IFELSE([$3],
151 [eval "AS_TR_SH([cc_cv_attribute_$1])='yes'"],
152 [eval "AS_TR_SH([cc_cv_attribute_$1])='no'"])
153 CFLAGS="$ac_save_CFLAGS"
154 ])
155
156 AS_IF([eval test x$]AS_TR_SH([cc_cv_attribute_$1])[ = xyes],
157 [AC_DEFINE(
158 AS_TR_CPP([SUPPORT_ATTRIBUTE_$1]), 1,
159 [Define this if the compiler supports __attribute__(( ifelse([$2], , [$1], [$2]) ))]
160 )
161 $4],
162 [$5])
163])
164
165AC_DEFUN([CC_ATTRIBUTE_CONSTRUCTOR], [
166 CC_CHECK_ATTRIBUTE(
167 [constructor],,
168 [void __attribute__((constructor)) ctor() { int a; }],
169 [$1], [$2])
170])
171
172AC_DEFUN([CC_ATTRIBUTE_FORMAT], [
173 CC_CHECK_ATTRIBUTE(
174 [format], [format(printf, n, n)],
175 [void __attribute__((format(printf, 1, 2))) printflike(const char *fmt, ...) { fmt = (void *)0; }],
176 [$1], [$2])
177])
178
179AC_DEFUN([CC_ATTRIBUTE_FORMAT_ARG], [
180 CC_CHECK_ATTRIBUTE(
181 [format_arg], [format_arg(printf)],
182 [char *__attribute__((format_arg(1))) gettextlike(const char *fmt) { fmt = (void *)0; }],
183 [$1], [$2])
184])
185
186AC_DEFUN([CC_ATTRIBUTE_VISIBILITY], [
187 CC_CHECK_ATTRIBUTE(
188 [visibility_$1], [visibility("$1")],
189 [void __attribute__((visibility("$1"))) $1_function() { }],
190 [$2], [$3])
191])
192
193AC_DEFUN([CC_ATTRIBUTE_NONNULL], [
194 CC_CHECK_ATTRIBUTE(
195 [nonnull], [nonnull()],
196 [void __attribute__((nonnull())) some_function(void *foo, void *bar) { foo = (void*)0; bar = (void*)0; }],
197 [$1], [$2])
198])
199
200AC_DEFUN([CC_ATTRIBUTE_UNUSED], [
201 CC_CHECK_ATTRIBUTE(
202 [unused], ,
203 [void some_function(void *foo, __attribute__((unused)) void *bar);],
204 [$1], [$2])
205])
206
207AC_DEFUN([CC_ATTRIBUTE_SENTINEL], [
208 CC_CHECK_ATTRIBUTE(
209 [sentinel], ,
210 [void some_function(void *foo, ...) __attribute__((sentinel));],
211 [$1], [$2])
212])
213
214AC_DEFUN([CC_ATTRIBUTE_DEPRECATED], [
215 CC_CHECK_ATTRIBUTE(
216 [deprecated], ,
217 [void some_function(void *foo, ...) __attribute__((deprecated));],
218 [$1], [$2])
219])
220
221AC_DEFUN([CC_ATTRIBUTE_ALIAS], [
222 CC_CHECK_ATTRIBUTE(
223 [alias], [weak, alias],
224 [void other_function(void *foo) { }
225 void some_function(void *foo) __attribute__((weak, alias("other_function")));],
226 [$1], [$2])
227])
228
229AC_DEFUN([CC_ATTRIBUTE_MALLOC], [
230 CC_CHECK_ATTRIBUTE(
231 [malloc], ,
232 [void * __attribute__((malloc)) my_alloc(int n);],
233 [$1], [$2])
234])
235
236AC_DEFUN([CC_ATTRIBUTE_PACKED], [
237 CC_CHECK_ATTRIBUTE(
238 [packed], ,
239 [struct astructure { char a; int b; long c; void *d; } __attribute__((packed));],
240 [$1], [$2])
241])
242
243AC_DEFUN([CC_ATTRIBUTE_CONST], [
244 CC_CHECK_ATTRIBUTE(
245 [const], ,
246 [int __attribute__((const)) twopow(int n) { return 1 << n; } ],
247 [$1], [$2])
248])
249
250AC_DEFUN([CC_FLAG_VISIBILITY], [
251 AC_REQUIRE([CC_CHECK_WERROR])
252 AC_CACHE_CHECK([if $CC supports -fvisibility=hidden],
253 [cc_cv_flag_visibility],
254 [cc_flag_visibility_save_CFLAGS="$CFLAGS"
255 CFLAGS="$CFLAGS $cc_cv_werror"
256 CC_CHECK_CFLAGS_SILENT([-fvisibility=hidden],
257 cc_cv_flag_visibility='yes',
258 cc_cv_flag_visibility='no')
259 CFLAGS="$cc_flag_visibility_save_CFLAGS"])
260
261 AS_IF([test "x$cc_cv_flag_visibility" = "xyes"],
262 [AC_DEFINE([SUPPORT_FLAG_VISIBILITY], 1,
263 [Define this if the compiler supports the -fvisibility flag])
264 $1],
265 [$2])
266])
267
268AC_DEFUN([CC_FUNC_EXPECT], [
269 AC_REQUIRE([CC_CHECK_WERROR])
270 AC_CACHE_CHECK([if compiler has __builtin_expect function],
271 [cc_cv_func_expect],
272 [ac_save_CFLAGS="$CFLAGS"
273 CFLAGS="$CFLAGS $cc_cv_werror"
274 AC_COMPILE_IFELSE(
275 [int some_function() {
276 int a = 3;
277 return (int)__builtin_expect(a, 3);
278 }],
279 [cc_cv_func_expect=yes],
280 [cc_cv_func_expect=no])
281 CFLAGS="$ac_save_CFLAGS"
282 ])
283
284 AS_IF([test "x$cc_cv_func_expect" = "xyes"],
285 [AC_DEFINE([SUPPORT__BUILTIN_EXPECT], 1,
286 [Define this if the compiler supports __builtin_expect() function])
287 $1],
288 [$2])
289])
290
291AC_DEFUN([CC_ATTRIBUTE_ALIGNED], [
292 AC_REQUIRE([CC_CHECK_WERROR])
293 AC_CACHE_CHECK([highest __attribute__ ((aligned ())) supported],
294 [cc_cv_attribute_aligned],
295 [ac_save_CFLAGS="$CFLAGS"
296 CFLAGS="$CFLAGS $cc_cv_werror"
297 for cc_attribute_align_try in 64 32 16 8 4 2; do
298 AC_COMPILE_IFELSE([
299 int main() {
300 static char c __attribute__ ((aligned($cc_attribute_align_try))) = 0;
301 return c;
302 }], [cc_cv_attribute_aligned=$cc_attribute_align_try; break])
303 done
304 CFLAGS="$ac_save_CFLAGS"
305 ])
306
307 if test "x$cc_cv_attribute_aligned" != "x"; then
308 AC_DEFINE_UNQUOTED([ATTRIBUTE_ALIGNED_MAX], [$cc_cv_attribute_aligned],
309 [Define the highest alignment supported])
310 fi
311])