ax_pthread.m4
1 # =========================================================================== 2 # http://www.nongnu.org/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 # ACTION-IF-FOUND is a list of shell commands to run if a threads library 37 # is found, and ACTION-IF-NOT-FOUND is a list of commands to run it if it 38 # is not found. If ACTION-IF-FOUND is not specified, the default action 39 # will define HAVE_PTHREAD. 40 # 41 # Please let the authors know if this macro fails on any platform, or if 42 # you have any other suggestions or comments. This macro was based on work 43 # by SGJ on autoconf scripts for FFTW (http://www.fftw.org/) (with help 44 # from M. Frigo), as well as ac_pthread and hb_pthread macros posted by 45 # Alejandro Forero Cuervo to the autoconf macro repository. We are also 46 # grateful for the helpful feedback of numerous users. 47 # 48 # LICENSE 49 # 50 # Copyright (c) 2008 Steven G. Johnson <stevenj@alum.mit.edu> 51 # 52 # This program is free software: you can redistribute it and/or modify it 53 # under the terms of the GNU General Public License as published by the 54 # Free Software Foundation, either version 3 of the License, or (at your 55 # option) any later version. 56 # 57 # This program is distributed in the hope that it will be useful, but 58 # WITHOUT ANY WARRANTY; without even the implied warranty of 59 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General 60 # Public License for more details. 61 # 62 # You should have received a copy of the GNU General Public License along 63 # with this program. If not, see <http://www.gnu.org/licenses/>. 64 # 65 # As a special exception, the respective Autoconf Macro's copyright owner 66 # gives unlimited permission to copy, distribute and modify the configure 67 # scripts that are the output of Autoconf when processing the Macro. You 68 # need not follow the terms of the GNU General Public License when using 69 # or distributing such scripts, even though portions of the text of the 70 # Macro appear in them. The GNU General Public License (GPL) does govern 71 # all other use of the material that constitutes the Autoconf Macro. 72 # 73 # This special exception to the GPL applies to versions of the Autoconf 74 # Macro released by the Autoconf Archive. When you make and distribute a 75 # modified version of the Autoconf Macro, you may extend this special 76 # exception to the GPL to apply to your modified version as well. 77 78 #serial 6 79 80 AU_ALIAS([ACX_PTHREAD], [AX_PTHREAD]) 81 AC_DEFUN([AX_PTHREAD], [ 82 AC_REQUIRE([AC_CANONICAL_HOST]) 83 AC_LANG_SAVE 84 AC_LANG_C 85 ax_pthread_ok=no 86 87 # We used to check for pthread.h first, but this fails if pthread.h 88 # requires special compiler flags (e.g. on True64 or Sequent). 89 # It gets checked for in the link test anyway. 90 91 # First of all, check if the user has set any of the PTHREAD_LIBS, 92 # etcetera environment variables, and if threads linking works using 93 # them: 94 if test x"$PTHREAD_LIBS$PTHREAD_CFLAGS" != x; then 95 save_CFLAGS="$CFLAGS" 96 CFLAGS="$CFLAGS $PTHREAD_CFLAGS" 97 save_LIBS="$LIBS" 98 LIBS="$PTHREAD_LIBS $LIBS" 99 AC_MSG_CHECKING([for pthread_join in LIBS=$PTHREAD_LIBS with CFLAGS=$PTHREAD_CFLAGS]) 100 AC_TRY_LINK_FUNC(pthread_join, ax_pthread_ok=yes) 101 AC_MSG_RESULT($ax_pthread_ok) 102 if test x"$ax_pthread_ok" = xno; then 103 PTHREAD_LIBS="" 104 PTHREAD_CFLAGS="" 105 fi 106 LIBS="$save_LIBS" 107 CFLAGS="$save_CFLAGS" 108 fi 109 110 # We must check for the threads library under a number of different 111 # names; the ordering is very important because some systems 112 # (e.g. DEC) have both -lpthread and -lpthreads, where one of the 113 # libraries is broken (non-POSIX). 114 115 # Create a list of thread flags to try. Items starting with a "-" are 116 # C compiler flags, and other items are library names, except for "none" 117 # which indicates that we try without any flags at all, and "pthread-config" 118 # which is a program returning the flags for the Pth emulation library. 119 120 ax_pthread_flags="pthreads none -Kthread -kthread lthread -pthread -pthreads -mthreads pthread --thread-safe -mt pthread-config" 121 122 # The ordering *is* (sometimes) important. Some notes on the 123 # individual items follow: 124 125 # pthreads: AIX (must check this before -lpthread) 126 # none: in case threads are in libc; should be tried before -Kthread and 127 # other compiler flags to prevent continual compiler warnings 128 # -Kthread: Sequent (threads in libc, but -Kthread needed for pthread.h) 129 # -kthread: FreeBSD kernel threads (preferred to -pthread since SMP-able) 130 # lthread: LinuxThreads port on FreeBSD (also preferred to -pthread) 131 # -pthread: Linux/gcc (kernel threads), BSD/gcc (userland threads) 132 # -pthreads: Solaris/gcc 133 # -mthreads: Mingw32/gcc, Lynx/gcc 134 # -mt: Sun Workshop C (may only link SunOS threads [-lthread], but it 135 # doesn't hurt to check since this sometimes defines pthreads too; 136 # also defines -D_REENTRANT) 137 # ... -mt is also the pthreads flag for HP/aCC 138 # pthread: Linux, etcetera 139 # --thread-safe: KAI C++ 140 # pthread-config: use pthread-config program (for GNU Pth library) 141 142 case "${host_cpu}-${host_os}" in 143 *solaris*) 144 145 # On Solaris (at least, for some versions), libc contains stubbed 146 # (non-functional) versions of the pthreads routines, so link-based 147 # tests will erroneously succeed. (We need to link with -pthreads/-mt/ 148 # -lpthread.) (The stubs are missing pthread_cleanup_push, or rather 149 # a function called by this macro, so we could check for that, but 150 # who knows whether they'll stub that too in a future libc.) So, 151 # we'll just look for -pthreads and -lpthread first: 152 153 ax_pthread_flags="-pthreads pthread -mt -pthread $ax_pthread_flags" 154 ;; 155 156 *-darwin*) 157 acx_pthread_flags="-pthread $acx_pthread_flags" 158 ;; 159 esac 160 161 if test x"$ax_pthread_ok" = xno; then 162 for flag in $ax_pthread_flags; do 163 164 case $flag in 165 none) 166 AC_MSG_CHECKING([whether pthreads work without any flags]) 167 ;; 168 169 -*) 170 AC_MSG_CHECKING([whether pthreads work with $flag]) 171 PTHREAD_CFLAGS="$flag" 172 ;; 173 174 pthread-config) 175 AC_CHECK_PROG(ax_pthread_config, pthread-config, yes, no) 176 if test x"$ax_pthread_config" = xno; then continue; fi 177 PTHREAD_CFLAGS="`pthread-config --cflags`" 178 PTHREAD_LIBS="`pthread-config --ldflags` `pthread-config --libs`" 179 ;; 180 181 *) 182 AC_MSG_CHECKING([for the pthreads library -l$flag]) 183 PTHREAD_LIBS="-l$flag" 184 ;; 185 esac 186 187 save_LIBS="$LIBS" 188 save_CFLAGS="$CFLAGS" 189 LIBS="$PTHREAD_LIBS $LIBS" 190 CFLAGS="$CFLAGS $PTHREAD_CFLAGS" 191 192 # Check for various functions. We must include pthread.h, 193 # since some functions may be macros. (On the Sequent, we 194 # need a special flag -Kthread to make this header compile.) 195 # We check for pthread_join because it is in -lpthread on IRIX 196 # while pthread_create is in libc. We check for pthread_attr_init 197 # due to DEC craziness with -lpthreads. We check for 198 # pthread_cleanup_push because it is one of the few pthread 199 # functions on Solaris that doesn't have a non-functional libc stub. 200 # We try pthread_create on general principles. 201 AC_TRY_LINK([#include <pthread.h> 202 static void routine(void* a) {a=0;} 203 static void* start_routine(void* a) {return a;}], 204 [pthread_t th; pthread_attr_t attr; 205 pthread_join(th, 0); 206 pthread_attr_init(&attr); 207 pthread_cleanup_push(routine, 0); 208 pthread_create(&th,0,start_routine,0); 209 pthread_cleanup_pop(0); ], 210 [ax_pthread_ok=yes]) 211 212 LIBS="$save_LIBS" 213 CFLAGS="$save_CFLAGS" 214 215 AC_MSG_RESULT($ax_pthread_ok) 216 if test "x$ax_pthread_ok" = xyes; then 217 break; 218 fi 219 220 PTHREAD_LIBS="" 221 PTHREAD_CFLAGS="" 222 done 223 fi 224 225 # Various other checks: 226 if test "x$ax_pthread_ok" = xyes; then 227 save_LIBS="$LIBS" 228 LIBS="$PTHREAD_LIBS $LIBS" 229 save_CFLAGS="$CFLAGS" 230 CFLAGS="$CFLAGS $PTHREAD_CFLAGS" 231 232 # Detect AIX lossage: JOINABLE attribute is called UNDETACHED. 233 AC_MSG_CHECKING([for joinable pthread attribute]) 234 attr_name=unknown 235 for attr in PTHREAD_CREATE_JOINABLE PTHREAD_CREATE_UNDETACHED; do 236 AC_TRY_LINK([#include <pthread.h>], [int attr=$attr; return attr;], 237 [attr_name=$attr; break]) 238 done 239 AC_MSG_RESULT($attr_name) 240 if test "$attr_name" != PTHREAD_CREATE_JOINABLE; then 241 AC_DEFINE_UNQUOTED(PTHREAD_CREATE_JOINABLE, $attr_name, 242 [Define to necessary symbol if this constant 243 uses a non-standard name on your system.]) 244 fi 245 246 AC_MSG_CHECKING([if more special flags are required for pthreads]) 247 flag=no 248 case "${host_cpu}-${host_os}" in 249 *-aix* | *-freebsd* | *-darwin*) flag="-D_THREAD_SAFE";; 250 *solaris* | *-osf* | *-hpux*) flag="-D_REENTRANT";; 251 esac 252 AC_MSG_RESULT(${flag}) 253 if test "x$flag" != xno; then 254 PTHREAD_CFLAGS="$flag $PTHREAD_CFLAGS" 255 fi 256 257 LIBS="$save_LIBS" 258 CFLAGS="$save_CFLAGS" 259 260 # More AIX lossage: must compile with xlc_r or cc_r 261 if test x"$GCC" != xyes; then 262 AC_CHECK_PROGS(PTHREAD_CC, xlc_r cc_r, ${CC}) 263 else 264 PTHREAD_CC=$CC 265 fi 266 else 267 PTHREAD_CC="$CC" 268 fi 269 270 AC_SUBST(PTHREAD_LIBS) 271 AC_SUBST(PTHREAD_CFLAGS) 272 AC_SUBST(PTHREAD_CC) 273 274 # Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND: 275 if test x"$ax_pthread_ok" = xyes; then 276 ifelse([$1],,AC_DEFINE(HAVE_PTHREAD,1,[Define if you have POSIX threads libraries and header files.]),[$1]) 277 : 278 else 279 ax_pthread_ok=no 280 $2 281 fi 282 AC_LANG_RESTORE 283 ])dnl AX_PTHREAD