|
1 # This was retrieved from |
|
2 # http://svn.0pointer.de/viewvc/trunk/common/acx_pthread.m4?revision=1277&root=avahi |
|
3 # See also (perhaps for new versions?) |
|
4 # http://svn.0pointer.de/viewvc/trunk/common/acx_pthread.m4?root=avahi |
|
5 # |
|
6 # We've rewritten the inconsistency check code (from avahi), to work |
|
7 # more broadly. In particular, it no longer assumes ld accepts -zdefs. |
|
8 # This caused a restructing of the code, but the functionality has only |
|
9 # changed a little. |
|
10 |
|
11 dnl @synopsis ACX_PTHREAD([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]]) |
|
12 dnl |
|
13 dnl @summary figure out how to build C programs using POSIX threads |
|
14 dnl |
|
15 dnl This macro figures out how to build C programs using POSIX threads. |
|
16 dnl It sets the PTHREAD_LIBS output variable to the threads library and |
|
17 dnl linker flags, and the PTHREAD_CFLAGS output variable to any special |
|
18 dnl C compiler flags that are needed. (The user can also force certain |
|
19 dnl compiler flags/libs to be tested by setting these environment |
|
20 dnl variables.) |
|
21 dnl |
|
22 dnl Also sets PTHREAD_CC to any special C compiler that is needed for |
|
23 dnl multi-threaded programs (defaults to the value of CC otherwise). |
|
24 dnl (This is necessary on AIX to use the special cc_r compiler alias.) |
|
25 dnl |
|
26 dnl NOTE: You are assumed to not only compile your program with these |
|
27 dnl flags, but also link it with them as well. e.g. you should link |
|
28 dnl with $PTHREAD_CC $CFLAGS $PTHREAD_CFLAGS $LDFLAGS ... $PTHREAD_LIBS |
|
29 dnl $LIBS |
|
30 dnl |
|
31 dnl If you are only building threads programs, you may wish to use |
|
32 dnl these variables in your default LIBS, CFLAGS, and CC: |
|
33 dnl |
|
34 dnl LIBS="$PTHREAD_LIBS $LIBS" |
|
35 dnl CFLAGS="$CFLAGS $PTHREAD_CFLAGS" |
|
36 dnl CC="$PTHREAD_CC" |
|
37 dnl |
|
38 dnl In addition, if the PTHREAD_CREATE_JOINABLE thread-attribute |
|
39 dnl constant has a nonstandard name, defines PTHREAD_CREATE_JOINABLE to |
|
40 dnl that name (e.g. PTHREAD_CREATE_UNDETACHED on AIX). |
|
41 dnl |
|
42 dnl ACTION-IF-FOUND is a list of shell commands to run if a threads |
|
43 dnl library is found, and ACTION-IF-NOT-FOUND is a list of commands to |
|
44 dnl run it if it is not found. If ACTION-IF-FOUND is not specified, the |
|
45 dnl default action will define HAVE_PTHREAD. |
|
46 dnl |
|
47 dnl Please let the authors know if this macro fails on any platform, or |
|
48 dnl if you have any other suggestions or comments. This macro was based |
|
49 dnl on work by SGJ on autoconf scripts for FFTW (www.fftw.org) (with |
|
50 dnl help from M. Frigo), as well as ac_pthread and hb_pthread macros |
|
51 dnl posted by Alejandro Forero Cuervo to the autoconf macro repository. |
|
52 dnl We are also grateful for the helpful feedback of numerous users. |
|
53 dnl |
|
54 dnl @category InstalledPackages |
|
55 dnl @author Steven G. Johnson <stevenj@alum.mit.edu> |
|
56 dnl @version 2006-05-29 |
|
57 dnl @license GPLWithACException |
|
58 dnl |
|
59 dnl Checks for GCC shared/pthread inconsistency based on work by |
|
60 dnl Marcin Owsiany <marcin@owsiany.pl> |
|
61 |
|
62 |
|
63 AC_DEFUN([ACX_PTHREAD], [ |
|
64 AC_REQUIRE([AC_CANONICAL_HOST]) |
|
65 AC_LANG_SAVE |
|
66 AC_LANG_C |
|
67 acx_pthread_ok=no |
|
68 |
|
69 # We used to check for pthread.h first, but this fails if pthread.h |
|
70 # requires special compiler flags (e.g. on True64 or Sequent). |
|
71 # It gets checked for in the link test anyway. |
|
72 |
|
73 # First of all, check if the user has set any of the PTHREAD_LIBS, |
|
74 # etcetera environment variables, and if threads linking works using |
|
75 # them: |
|
76 if test x"$PTHREAD_LIBS$PTHREAD_CFLAGS" != x; then |
|
77 save_CFLAGS="$CFLAGS" |
|
78 CFLAGS="$CFLAGS $PTHREAD_CFLAGS" |
|
79 save_LIBS="$LIBS" |
|
80 LIBS="$PTHREAD_LIBS $LIBS" |
|
81 AC_MSG_CHECKING([for pthread_join in LIBS=$PTHREAD_LIBS with CFLAGS=$PTHREAD_CFLAGS]) |
|
82 AC_TRY_LINK_FUNC(pthread_join, acx_pthread_ok=yes) |
|
83 AC_MSG_RESULT($acx_pthread_ok) |
|
84 if test x"$acx_pthread_ok" = xno; then |
|
85 PTHREAD_LIBS="" |
|
86 PTHREAD_CFLAGS="" |
|
87 fi |
|
88 LIBS="$save_LIBS" |
|
89 CFLAGS="$save_CFLAGS" |
|
90 fi |
|
91 |
|
92 # We must check for the threads library under a number of different |
|
93 # names; the ordering is very important because some systems |
|
94 # (e.g. DEC) have both -lpthread and -lpthreads, where one of the |
|
95 # libraries is broken (non-POSIX). |
|
96 |
|
97 # Create a list of thread flags to try. Items starting with a "-" are |
|
98 # C compiler flags, and other items are library names, except for "none" |
|
99 # which indicates that we try without any flags at all, and "pthread-config" |
|
100 # which is a program returning the flags for the Pth emulation library. |
|
101 |
|
102 acx_pthread_flags="pthreads none -Kthread -kthread lthread -pthread -pthreads -mthreads pthread --thread-safe -mt pthread-config" |
|
103 |
|
104 # The ordering *is* (sometimes) important. Some notes on the |
|
105 # individual items follow: |
|
106 |
|
107 # pthreads: AIX (must check this before -lpthread) |
|
108 # none: in case threads are in libc; should be tried before -Kthread and |
|
109 # other compiler flags to prevent continual compiler warnings |
|
110 # -Kthread: Sequent (threads in libc, but -Kthread needed for pthread.h) |
|
111 # -kthread: FreeBSD kernel threads (preferred to -pthread since SMP-able) |
|
112 # lthread: LinuxThreads port on FreeBSD (also preferred to -pthread) |
|
113 # -pthread: Linux/gcc (kernel threads), BSD/gcc (userland threads) |
|
114 # -pthreads: Solaris/gcc |
|
115 # -mthreads: Mingw32/gcc, Lynx/gcc |
|
116 # -mt: Sun Workshop C (may only link SunOS threads [-lthread], but it |
|
117 # doesn't hurt to check since this sometimes defines pthreads too; |
|
118 # also defines -D_REENTRANT) |
|
119 # ... -mt is also the pthreads flag for HP/aCC |
|
120 # pthread: Linux, etcetera |
|
121 # --thread-safe: KAI C++ |
|
122 # pthread-config: use pthread-config program (for GNU Pth library) |
|
123 |
|
124 case "${host_cpu}-${host_os}" in |
|
125 *solaris*) |
|
126 |
|
127 # On Solaris (at least, for some versions), libc contains stubbed |
|
128 # (non-functional) versions of the pthreads routines, so link-based |
|
129 # tests will erroneously succeed. (We need to link with -pthreads/-mt/ |
|
130 # -lpthread.) (The stubs are missing pthread_cleanup_push, or rather |
|
131 # a function called by this macro, so we could check for that, but |
|
132 # who knows whether they'll stub that too in a future libc.) So, |
|
133 # we'll just look for -pthreads and -lpthread first: |
|
134 |
|
135 acx_pthread_flags="-pthreads pthread -mt -pthread $acx_pthread_flags" |
|
136 ;; |
|
137 esac |
|
138 |
|
139 if test x"$acx_pthread_ok" = xno; then |
|
140 for flag in $acx_pthread_flags; do |
|
141 |
|
142 case $flag in |
|
143 none) |
|
144 AC_MSG_CHECKING([whether pthreads work without any flags]) |
|
145 ;; |
|
146 |
|
147 -*) |
|
148 AC_MSG_CHECKING([whether pthreads work with $flag]) |
|
149 PTHREAD_CFLAGS="$flag" |
|
150 ;; |
|
151 |
|
152 pthread-config) |
|
153 AC_CHECK_PROG(acx_pthread_config, pthread-config, yes, no) |
|
154 if test x"$acx_pthread_config" = xno; then continue; fi |
|
155 PTHREAD_CFLAGS="`pthread-config --cflags`" |
|
156 PTHREAD_LIBS="`pthread-config --ldflags` `pthread-config --libs`" |
|
157 ;; |
|
158 |
|
159 *) |
|
160 AC_MSG_CHECKING([for the pthreads library -l$flag]) |
|
161 PTHREAD_LIBS="-l$flag" |
|
162 ;; |
|
163 esac |
|
164 |
|
165 save_LIBS="$LIBS" |
|
166 save_CFLAGS="$CFLAGS" |
|
167 LIBS="$PTHREAD_LIBS $LIBS" |
|
168 CFLAGS="$CFLAGS $PTHREAD_CFLAGS" |
|
169 |
|
170 # Check for various functions. We must include pthread.h, |
|
171 # since some functions may be macros. (On the Sequent, we |
|
172 # need a special flag -Kthread to make this header compile.) |
|
173 # We check for pthread_join because it is in -lpthread on IRIX |
|
174 # while pthread_create is in libc. We check for pthread_attr_init |
|
175 # due to DEC craziness with -lpthreads. We check for |
|
176 # pthread_cleanup_push because it is one of the few pthread |
|
177 # functions on Solaris that doesn't have a non-functional libc stub. |
|
178 # We try pthread_create on general principles. |
|
179 AC_TRY_LINK([#include <pthread.h>], |
|
180 [pthread_t th; pthread_join(th, 0); |
|
181 pthread_attr_init(0); pthread_cleanup_push(0, 0); |
|
182 pthread_create(0,0,0,0); pthread_cleanup_pop(0); ], |
|
183 [acx_pthread_ok=yes]) |
|
184 |
|
185 LIBS="$save_LIBS" |
|
186 CFLAGS="$save_CFLAGS" |
|
187 |
|
188 AC_MSG_RESULT($acx_pthread_ok) |
|
189 if test "x$acx_pthread_ok" = xyes; then |
|
190 break; |
|
191 fi |
|
192 |
|
193 PTHREAD_LIBS="" |
|
194 PTHREAD_CFLAGS="" |
|
195 done |
|
196 fi |
|
197 |
|
198 # Various other checks: |
|
199 if test "x$acx_pthread_ok" = xyes; then |
|
200 save_LIBS="$LIBS" |
|
201 LIBS="$PTHREAD_LIBS $LIBS" |
|
202 save_CFLAGS="$CFLAGS" |
|
203 CFLAGS="$CFLAGS $PTHREAD_CFLAGS" |
|
204 |
|
205 # Detect AIX lossage: JOINABLE attribute is called UNDETACHED. |
|
206 AC_MSG_CHECKING([for joinable pthread attribute]) |
|
207 attr_name=unknown |
|
208 for attr in PTHREAD_CREATE_JOINABLE PTHREAD_CREATE_UNDETACHED; do |
|
209 AC_TRY_LINK([#include <pthread.h>], [int attr=$attr; return attr;], |
|
210 [attr_name=$attr; break]) |
|
211 done |
|
212 AC_MSG_RESULT($attr_name) |
|
213 if test "$attr_name" != PTHREAD_CREATE_JOINABLE; then |
|
214 AC_DEFINE_UNQUOTED(PTHREAD_CREATE_JOINABLE, $attr_name, |
|
215 [Define to necessary symbol if this constant |
|
216 uses a non-standard name on your system.]) |
|
217 fi |
|
218 |
|
219 AC_MSG_CHECKING([if more special flags are required for pthreads]) |
|
220 flag=no |
|
221 case "${host_cpu}-${host_os}" in |
|
222 *-aix* | *-freebsd* | *-darwin*) flag="-D_THREAD_SAFE";; |
|
223 *solaris* | *-osf* | *-hpux*) flag="-D_REENTRANT";; |
|
224 esac |
|
225 AC_MSG_RESULT(${flag}) |
|
226 if test "x$flag" != xno; then |
|
227 PTHREAD_CFLAGS="$flag $PTHREAD_CFLAGS" |
|
228 fi |
|
229 |
|
230 LIBS="$save_LIBS" |
|
231 CFLAGS="$save_CFLAGS" |
|
232 # More AIX lossage: must compile with xlc_r or cc_r |
|
233 if test x"$GCC" != xyes; then |
|
234 AC_CHECK_PROGS(PTHREAD_CC, xlc_r cc_r, ${CC}) |
|
235 else |
|
236 PTHREAD_CC=$CC |
|
237 fi |
|
238 |
|
239 # The next part tries to detect GCC inconsistency with -shared on some |
|
240 # architectures and systems. The problem is that in certain |
|
241 # configurations, when -shared is specified, GCC "forgets" to |
|
242 # internally use various flags which are still necessary. |
|
243 |
|
244 # |
|
245 # Prepare the flags |
|
246 # |
|
247 save_CFLAGS="$CFLAGS" |
|
248 save_LIBS="$LIBS" |
|
249 save_CC="$CC" |
|
250 |
|
251 # Try with the flags determined by the earlier checks. |
|
252 # |
|
253 # -Wl,-z,defs forces link-time symbol resolution, so that the |
|
254 # linking checks with -shared actually have any value |
|
255 # |
|
256 # FIXME: -fPIC is required for -shared on many architectures, |
|
257 # so we specify it here, but the right way would probably be to |
|
258 # properly detect whether it is actually required. |
|
259 CFLAGS="-shared -fPIC -Wl,-z,defs $CFLAGS $PTHREAD_CFLAGS" |
|
260 LIBS="$PTHREAD_LIBS $LIBS" |
|
261 CC="$PTHREAD_CC" |
|
262 |
|
263 # In order not to create several levels of indentation, we test |
|
264 # the value of "$done" until we find the cure or run out of ideas. |
|
265 done="no" |
|
266 |
|
267 # First, make sure the CFLAGS we added are actually accepted by our |
|
268 # compiler. If not (and OS X's ld, for instance, does not accept -z), |
|
269 # then we can't do this test. |
|
270 if test x"$done" = xno; then |
|
271 AC_MSG_CHECKING([whether to check for GCC pthread/shared inconsistencies]) |
|
272 AC_TRY_LINK(,, , [done=yes]) |
|
273 |
|
274 if test "x$done" = xyes ; then |
|
275 AC_MSG_RESULT([no]) |
|
276 else |
|
277 AC_MSG_RESULT([yes]) |
|
278 fi |
|
279 fi |
|
280 |
|
281 if test x"$done" = xno; then |
|
282 AC_MSG_CHECKING([whether -pthread is sufficient with -shared]) |
|
283 AC_TRY_LINK([#include <pthread.h>], |
|
284 [pthread_t th; pthread_join(th, 0); |
|
285 pthread_attr_init(0); pthread_cleanup_push(0, 0); |
|
286 pthread_create(0,0,0,0); pthread_cleanup_pop(0); ], |
|
287 [done=yes]) |
|
288 |
|
289 if test "x$done" = xyes; then |
|
290 AC_MSG_RESULT([yes]) |
|
291 else |
|
292 AC_MSG_RESULT([no]) |
|
293 fi |
|
294 fi |
|
295 |
|
296 # |
|
297 # Linux gcc on some architectures such as mips/mipsel forgets |
|
298 # about -lpthread |
|
299 # |
|
300 if test x"$done" = xno; then |
|
301 AC_MSG_CHECKING([whether -lpthread fixes that]) |
|
302 LIBS="-lpthread $PTHREAD_LIBS $save_LIBS" |
|
303 AC_TRY_LINK([#include <pthread.h>], |
|
304 [pthread_t th; pthread_join(th, 0); |
|
305 pthread_attr_init(0); pthread_cleanup_push(0, 0); |
|
306 pthread_create(0,0,0,0); pthread_cleanup_pop(0); ], |
|
307 [done=yes]) |
|
308 |
|
309 if test "x$done" = xyes; then |
|
310 AC_MSG_RESULT([yes]) |
|
311 PTHREAD_LIBS="-lpthread $PTHREAD_LIBS" |
|
312 else |
|
313 AC_MSG_RESULT([no]) |
|
314 fi |
|
315 fi |
|
316 # |
|
317 # FreeBSD 4.10 gcc forgets to use -lc_r instead of -lc |
|
318 # |
|
319 if test x"$done" = xno; then |
|
320 AC_MSG_CHECKING([whether -lc_r fixes that]) |
|
321 LIBS="-lc_r $PTHREAD_LIBS $save_LIBS" |
|
322 AC_TRY_LINK([#include <pthread.h>], |
|
323 [pthread_t th; pthread_join(th, 0); |
|
324 pthread_attr_init(0); pthread_cleanup_push(0, 0); |
|
325 pthread_create(0,0,0,0); pthread_cleanup_pop(0); ], |
|
326 [done=yes]) |
|
327 |
|
328 if test "x$done" = xyes; then |
|
329 AC_MSG_RESULT([yes]) |
|
330 PTHREAD_LIBS="-lc_r $PTHREAD_LIBS" |
|
331 else |
|
332 AC_MSG_RESULT([no]) |
|
333 fi |
|
334 fi |
|
335 if test x"$done" = xno; then |
|
336 # OK, we have run out of ideas |
|
337 AC_MSG_WARN([Impossible to determine how to use pthreads with shared libraries]) |
|
338 |
|
339 # so it's not safe to assume that we may use pthreads |
|
340 acx_pthread_ok=no |
|
341 fi |
|
342 |
|
343 CFLAGS="$save_CFLAGS" |
|
344 LIBS="$save_LIBS" |
|
345 CC="$save_CC" |
|
346 else |
|
347 PTHREAD_CC="$CC" |
|
348 fi |
|
349 |
|
350 AC_SUBST(PTHREAD_LIBS) |
|
351 AC_SUBST(PTHREAD_CFLAGS) |
|
352 AC_SUBST(PTHREAD_CC) |
|
353 |
|
354 # Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND: |
|
355 if test x"$acx_pthread_ok" = xyes; then |
|
356 ifelse([$1],,AC_DEFINE(HAVE_PTHREAD,1,[Define if you have POSIX threads libraries and header files.]),[$1]) |
|
357 : |
|
358 else |
|
359 acx_pthread_ok=no |
|
360 $2 |
|
361 fi |
|
362 AC_LANG_RESTORE |
|
363 ])dnl ACX_PTHREAD |