Update library current version due to adding destroy API
[urcu.git] / m4 / ax_pthread.m4
CommitLineData
074c3a1b
MJ
1# ===========================================================================
2# http://www.gnu.org/software/autoconf-archive/ax_pthread.html
3# ===========================================================================
4#
5# SYNOPSIS
6#
7# AX_PTHREAD([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]])
8#
9# DESCRIPTION
10#
11# This macro figures out how to build C programs using POSIX threads. It
12# sets the PTHREAD_LIBS output variable to the threads library and linker
13# flags, and the PTHREAD_CFLAGS output variable to any special C compiler
14# flags that are needed. (The user can also force certain compiler
15# flags/libs to be tested by setting these environment variables.)
16#
17# Also sets PTHREAD_CC to any special C compiler that is needed for
18# multi-threaded programs (defaults to the value of CC otherwise). (This
19# is necessary on AIX to use the special cc_r compiler alias.)
20#
21# NOTE: You are assumed to not only compile your program with these flags,
22# but also link it with them as well. e.g. you should link with
23# $PTHREAD_CC $CFLAGS $PTHREAD_CFLAGS $LDFLAGS ... $PTHREAD_LIBS $LIBS
24#
25# If you are only building threads programs, you may wish to use these
26# variables in your default LIBS, CFLAGS, and CC:
27#
28# LIBS="$PTHREAD_LIBS $LIBS"
29# CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
30# CC="$PTHREAD_CC"
31#
32# In addition, if the PTHREAD_CREATE_JOINABLE thread-attribute constant
33# has a nonstandard name, defines PTHREAD_CREATE_JOINABLE to that name
34# (e.g. PTHREAD_CREATE_UNDETACHED on AIX).
35#
36# Also HAVE_PTHREAD_PRIO_INHERIT is defined if pthread is found and the
37# PTHREAD_PRIO_INHERIT symbol is defined when compiling with
38# PTHREAD_CFLAGS.
39#
40# ACTION-IF-FOUND is a list of shell commands to run if a threads library
41# is found, and ACTION-IF-NOT-FOUND is a list of commands to run it if it
42# is not found. If ACTION-IF-FOUND is not specified, the default action
43# will define HAVE_PTHREAD.
44#
45# Please let the authors know if this macro fails on any platform, or if
46# you have any other suggestions or comments. This macro was based on work
47# by SGJ on autoconf scripts for FFTW (http://www.fftw.org/) (with help
48# from M. Frigo), as well as ac_pthread and hb_pthread macros posted by
49# Alejandro Forero Cuervo to the autoconf macro repository. We are also
50# grateful for the helpful feedback of numerous users.
51#
52# Updated for Autoconf 2.68 by Daniel Richard G.
53#
54# LICENSE
55#
56# Copyright (c) 2008 Steven G. Johnson <stevenj@alum.mit.edu>
57# Copyright (c) 2011 Daniel Richard G. <skunk@iSKUNK.ORG>
58#
59# This program is free software: you can redistribute it and/or modify it
60# under the terms of the GNU General Public License as published by the
61# Free Software Foundation, either version 3 of the License, or (at your
62# option) any later version.
63#
64# This program is distributed in the hope that it will be useful, but
65# WITHOUT ANY WARRANTY; without even the implied warranty of
66# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
67# Public License for more details.
68#
69# You should have received a copy of the GNU General Public License along
70# with this program. If not, see <http://www.gnu.org/licenses/>.
71#
72# As a special exception, the respective Autoconf Macro's copyright owner
73# gives unlimited permission to copy, distribute and modify the configure
74# scripts that are the output of Autoconf when processing the Macro. You
75# need not follow the terms of the GNU General Public License when using
76# or distributing such scripts, even though portions of the text of the
77# Macro appear in them. The GNU General Public License (GPL) does govern
78# all other use of the material that constitutes the Autoconf Macro.
79#
80# This special exception to the GPL applies to versions of the Autoconf
81# Macro released by the Autoconf Archive. When you make and distribute a
82# modified version of the Autoconf Macro, you may extend this special
83# exception to the GPL to apply to your modified version as well.
84
85#serial 21
86
87AU_ALIAS([ACX_PTHREAD], [AX_PTHREAD])
88AC_DEFUN([AX_PTHREAD], [
89AC_REQUIRE([AC_CANONICAL_HOST])
90AC_LANG_PUSH([C])
91ax_pthread_ok=no
92
93# We used to check for pthread.h first, but this fails if pthread.h
94# requires special compiler flags (e.g. on True64 or Sequent).
95# It gets checked for in the link test anyway.
96
97# First of all, check if the user has set any of the PTHREAD_LIBS,
98# etcetera environment variables, and if threads linking works using
99# them:
100if test x"$PTHREAD_LIBS$PTHREAD_CFLAGS" != x; then
101 save_CFLAGS="$CFLAGS"
102 CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
103 save_LIBS="$LIBS"
104 LIBS="$PTHREAD_LIBS $LIBS"
105 AC_MSG_CHECKING([for pthread_join in LIBS=$PTHREAD_LIBS with CFLAGS=$PTHREAD_CFLAGS])
106 AC_TRY_LINK_FUNC([pthread_join], [ax_pthread_ok=yes])
107 AC_MSG_RESULT([$ax_pthread_ok])
108 if test x"$ax_pthread_ok" = xno; then
109 PTHREAD_LIBS=""
110 PTHREAD_CFLAGS=""
111 fi
112 LIBS="$save_LIBS"
113 CFLAGS="$save_CFLAGS"
114fi
115
116# We must check for the threads library under a number of different
117# names; the ordering is very important because some systems
118# (e.g. DEC) have both -lpthread and -lpthreads, where one of the
119# libraries is broken (non-POSIX).
120
121# Create a list of thread flags to try. Items starting with a "-" are
122# C compiler flags, and other items are library names, except for "none"
123# which indicates that we try without any flags at all, and "pthread-config"
124# which is a program returning the flags for the Pth emulation library.
125
126ax_pthread_flags="pthreads none -Kthread -kthread lthread -pthread -pthreads -mthreads pthread --thread-safe -mt pthread-config"
127
128# The ordering *is* (sometimes) important. Some notes on the
129# individual items follow:
130
131# pthreads: AIX (must check this before -lpthread)
132# none: in case threads are in libc; should be tried before -Kthread and
133# other compiler flags to prevent continual compiler warnings
134# -Kthread: Sequent (threads in libc, but -Kthread needed for pthread.h)
135# -kthread: FreeBSD kernel threads (preferred to -pthread since SMP-able)
136# lthread: LinuxThreads port on FreeBSD (also preferred to -pthread)
137# -pthread: Linux/gcc (kernel threads), BSD/gcc (userland threads)
138# -pthreads: Solaris/gcc
139# -mthreads: Mingw32/gcc, Lynx/gcc
140# -mt: Sun Workshop C (may only link SunOS threads [-lthread], but it
141# doesn't hurt to check since this sometimes defines pthreads too;
142# also defines -D_REENTRANT)
143# ... -mt is also the pthreads flag for HP/aCC
144# pthread: Linux, etcetera
145# --thread-safe: KAI C++
146# pthread-config: use pthread-config program (for GNU Pth library)
147
148case ${host_os} in
149 solaris*)
150
151 # On Solaris (at least, for some versions), libc contains stubbed
152 # (non-functional) versions of the pthreads routines, so link-based
153 # tests will erroneously succeed. (We need to link with -pthreads/-mt/
154 # -lpthread.) (The stubs are missing pthread_cleanup_push, or rather
155 # a function called by this macro, so we could check for that, but
156 # who knows whether they'll stub that too in a future libc.) So,
157 # we'll just look for -pthreads and -lpthread first:
158
159 ax_pthread_flags="-pthreads pthread -mt -pthread $ax_pthread_flags"
160 ;;
161
162 darwin*)
163 ax_pthread_flags="-pthread $ax_pthread_flags"
164 ;;
165esac
166
167# Clang doesn't consider unrecognized options an error unless we specify
168# -Werror. We throw in some extra Clang-specific options to ensure that
169# this doesn't happen for GCC, which also accepts -Werror.
170
171AC_MSG_CHECKING([if compiler needs -Werror to reject unknown flags])
172save_CFLAGS="$CFLAGS"
173ax_pthread_extra_flags="-Werror"
174CFLAGS="$CFLAGS $ax_pthread_extra_flags -Wunknown-warning-option -Wsizeof-array-argument"
175AC_COMPILE_IFELSE([AC_LANG_PROGRAM([int foo(void);],[foo()])],
176 [AC_MSG_RESULT([yes])],
177 [ax_pthread_extra_flags=
178 AC_MSG_RESULT([no])])
179CFLAGS="$save_CFLAGS"
180
181if test x"$ax_pthread_ok" = xno; then
182for flag in $ax_pthread_flags; do
183
184 case $flag in
185 none)
186 AC_MSG_CHECKING([whether pthreads work without any flags])
187 ;;
188
189 -*)
190 AC_MSG_CHECKING([whether pthreads work with $flag])
191 PTHREAD_CFLAGS="$flag"
192 ;;
193
194 pthread-config)
195 AC_CHECK_PROG([ax_pthread_config], [pthread-config], [yes], [no])
196 if test x"$ax_pthread_config" = xno; then continue; fi
197 PTHREAD_CFLAGS="`pthread-config --cflags`"
198 PTHREAD_LIBS="`pthread-config --ldflags` `pthread-config --libs`"
199 ;;
200
201 *)
202 AC_MSG_CHECKING([for the pthreads library -l$flag])
203 PTHREAD_LIBS="-l$flag"
204 ;;
205 esac
206
207 save_LIBS="$LIBS"
208 save_CFLAGS="$CFLAGS"
209 LIBS="$PTHREAD_LIBS $LIBS"
210 CFLAGS="$CFLAGS $PTHREAD_CFLAGS $ax_pthread_extra_flags"
211
212 # Check for various functions. We must include pthread.h,
213 # since some functions may be macros. (On the Sequent, we
214 # need a special flag -Kthread to make this header compile.)
215 # We check for pthread_join because it is in -lpthread on IRIX
216 # while pthread_create is in libc. We check for pthread_attr_init
217 # due to DEC craziness with -lpthreads. We check for
218 # pthread_cleanup_push because it is one of the few pthread
219 # functions on Solaris that doesn't have a non-functional libc stub.
220 # We try pthread_create on general principles.
221 AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <pthread.h>
222 static void routine(void *a) { a = 0; }
223 static void *start_routine(void *a) { return a; }],
224 [pthread_t th; pthread_attr_t attr;
225 pthread_create(&th, 0, start_routine, 0);
226 pthread_join(th, 0);
227 pthread_attr_init(&attr);
228 pthread_cleanup_push(routine, 0);
229 pthread_cleanup_pop(0) /* ; */])],
230 [ax_pthread_ok=yes],
231 [])
232
233 LIBS="$save_LIBS"
234 CFLAGS="$save_CFLAGS"
235
236 AC_MSG_RESULT([$ax_pthread_ok])
237 if test "x$ax_pthread_ok" = xyes; then
238 break;
239 fi
240
241 PTHREAD_LIBS=""
242 PTHREAD_CFLAGS=""
243done
244fi
245
246# Various other checks:
247if test "x$ax_pthread_ok" = xyes; then
248 save_LIBS="$LIBS"
249 LIBS="$PTHREAD_LIBS $LIBS"
250 save_CFLAGS="$CFLAGS"
251 CFLAGS="$CFLAGS $PTHREAD_CFLAGS"
252
253 # Detect AIX lossage: JOINABLE attribute is called UNDETACHED.
254 AC_MSG_CHECKING([for joinable pthread attribute])
255 attr_name=unknown
256 for attr in PTHREAD_CREATE_JOINABLE PTHREAD_CREATE_UNDETACHED; do
257 AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <pthread.h>],
258 [int attr = $attr; return attr /* ; */])],
259 [attr_name=$attr; break],
260 [])
261 done
262 AC_MSG_RESULT([$attr_name])
263 if test "$attr_name" != PTHREAD_CREATE_JOINABLE; then
264 AC_DEFINE_UNQUOTED([PTHREAD_CREATE_JOINABLE], [$attr_name],
265 [Define to necessary symbol if this constant
266 uses a non-standard name on your system.])
267 fi
268
269 AC_MSG_CHECKING([if more special flags are required for pthreads])
270 flag=no
271 case ${host_os} in
272 aix* | freebsd* | darwin*) flag="-D_THREAD_SAFE";;
273 osf* | hpux*) flag="-D_REENTRANT";;
274 solaris*)
275 if test "$GCC" = "yes"; then
276 flag="-D_REENTRANT"
277 else
278 # TODO: What about Clang on Solaris?
279 flag="-mt -D_REENTRANT"
280 fi
281 ;;
282 esac
283 AC_MSG_RESULT([$flag])
284 if test "x$flag" != xno; then
285 PTHREAD_CFLAGS="$flag $PTHREAD_CFLAGS"
286 fi
287
288 AC_CACHE_CHECK([for PTHREAD_PRIO_INHERIT],
289 [ax_cv_PTHREAD_PRIO_INHERIT], [
290 AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <pthread.h>]],
291 [[int i = PTHREAD_PRIO_INHERIT;]])],
292 [ax_cv_PTHREAD_PRIO_INHERIT=yes],
293 [ax_cv_PTHREAD_PRIO_INHERIT=no])
294 ])
295 AS_IF([test "x$ax_cv_PTHREAD_PRIO_INHERIT" = "xyes"],
296 [AC_DEFINE([HAVE_PTHREAD_PRIO_INHERIT], [1], [Have PTHREAD_PRIO_INHERIT.])])
297
298 LIBS="$save_LIBS"
299 CFLAGS="$save_CFLAGS"
300
301 # More AIX lossage: compile with *_r variant
302 if test "x$GCC" != xyes; then
303 case $host_os in
304 aix*)
305 AS_CASE(["x/$CC"],
306 [x*/c89|x*/c89_128|x*/c99|x*/c99_128|x*/cc|x*/cc128|x*/xlc|x*/xlc_v6|x*/xlc128|x*/xlc128_v6],
307 [#handle absolute path differently from PATH based program lookup
308 AS_CASE(["x$CC"],
309 [x/*],
310 [AS_IF([AS_EXECUTABLE_P([${CC}_r])],[PTHREAD_CC="${CC}_r"])],
311 [AC_CHECK_PROGS([PTHREAD_CC],[${CC}_r],[$CC])])])
312 ;;
313 esac
314 fi
315fi
316
317test -n "$PTHREAD_CC" || PTHREAD_CC="$CC"
318
319AC_SUBST([PTHREAD_LIBS])
320AC_SUBST([PTHREAD_CFLAGS])
321AC_SUBST([PTHREAD_CC])
322
323# Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND:
324if test x"$ax_pthread_ok" = xyes; then
325 ifelse([$1],,[AC_DEFINE([HAVE_PTHREAD],[1],[Define if you have POSIX threads libraries and header files.])],[$1])
326 :
327else
328 ax_pthread_ok=no
329 $2
330fi
331AC_LANG_POP
332])dnl AX_PTHREAD
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