1# =========================================================================== 2# http://autoconf-archive.cryp.to/acx_pthread.html 3# =========================================================================== 4# 5# SYNOPSIS 6# 7# ACX_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# LAST MODIFICATION 49# 50# 2008-04-12 51# 52# COPYLEFT 53# 54# Copyright (c) 2008 Steven G. Johnson <stevenj@alum.mit.edu> 55# 56# This program is free software: you can redistribute it and/or modify it 57# under the terms of the GNU General Public License as published by the 58# Free Software Foundation, either version 3 of the License, or (at your 59# option) any later version. 60# 61# This program is distributed in the hope that it will be useful, but 62# WITHOUT ANY WARRANTY; without even the implied warranty of 63# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General 64# Public License for more details. 65# 66# You should have received a copy of the GNU General Public License along 67# with this program. If not, see <http://www.gnu.org/licenses/>. 68# 69# As a special exception, the respective Autoconf Macro's copyright owner 70# gives unlimited permission to copy, distribute and modify the configure 71# scripts that are the output of Autoconf when processing the Macro. You 72# need not follow the terms of the GNU General Public License when using 73# or distributing such scripts, even though portions of the text of the 74# Macro appear in them. The GNU General Public License (GPL) does govern 75# all other use of the material that constitutes the Autoconf Macro. 76# 77# This special exception to the GPL applies to versions of the Autoconf 78# Macro released by the Autoconf Macro Archive. When you make and 79# distribute a modified version of the Autoconf Macro, you may extend this 80# special exception to the GPL to apply to your modified version as well. 81 82AC_DEFUN([ACX_PTHREAD], [ 83AC_REQUIRE([AC_CANONICAL_HOST]) 84AC_LANG_SAVE 85AC_LANG_C 86acx_pthread_ok=no 87 88# We used to check for pthread.h first, but this fails if pthread.h 89# requires special compiler flags (e.g. on True64 or Sequent). 90# It gets checked for in the link test anyway. 91 92# First of all, check if the user has set any of the PTHREAD_LIBS, 93# etcetera environment variables, and if threads linking works using 94# them: 95if test x"$PTHREAD_LIBS$PTHREAD_CFLAGS" != x; then 96 save_CFLAGS="$CFLAGS" 97 CFLAGS="$CFLAGS $PTHREAD_CFLAGS" 98 save_LIBS="$LIBS" 99 LIBS="$PTHREAD_LIBS $LIBS" 100 AC_MSG_CHECKING([for pthread_join in LIBS=$PTHREAD_LIBS with CFLAGS=$PTHREAD_CFLAGS]) 101 AC_TRY_LINK_FUNC(pthread_join, acx_pthread_ok=yes) 102 AC_MSG_RESULT($acx_pthread_ok) 103 if test x"$acx_pthread_ok" = xno; then 104 PTHREAD_LIBS="" 105 PTHREAD_CFLAGS="" 106 fi 107 LIBS="$save_LIBS" 108 CFLAGS="$save_CFLAGS" 109fi 110 111# We must check for the threads library under a number of different 112# names; the ordering is very important because some systems 113# (e.g. DEC) have both -lpthread and -lpthreads, where one of the 114# libraries is broken (non-POSIX). 115 116# Create a list of thread flags to try. Items starting with a "-" are 117# C compiler flags, and other items are library names, except for "none" 118# which indicates that we try without any flags at all, and "pthread-config" 119# which is a program returning the flags for the Pth emulation library. 120 121acx_pthread_flags="pthreads none -Kthread -kthread lthread -pthread -pthreads -mthreads pthread --thread-safe -mt pthread-config" 122 123# The ordering *is* (sometimes) important. Some notes on the 124# individual items follow: 125 126# pthreads: AIX (must check this before -lpthread) 127# none: in case threads are in libc; should be tried before -Kthread and 128# other compiler flags to prevent continual compiler warnings 129# -Kthread: Sequent (threads in libc, but -Kthread needed for pthread.h) 130# -kthread: FreeBSD kernel threads (preferred to -pthread since SMP-able) 131# lthread: LinuxThreads port on FreeBSD (also preferred to -pthread) 132# -pthread: Linux/gcc (kernel threads), BSD/gcc (userland threads) 133# -pthreads: Solaris/gcc 134# -mthreads: Mingw32/gcc, Lynx/gcc 135# -mt: Sun Workshop C (may only link SunOS threads [-lthread], but it 136# doesn't hurt to check since this sometimes defines pthreads too; 137# also defines -D_REENTRANT) 138# ... -mt is also the pthreads flag for HP/aCC 139# pthread: Linux, etcetera 140# --thread-safe: KAI C++ 141# pthread-config: use pthread-config program (for GNU Pth library) 142 143case "${host_cpu}-${host_os}" in 144 *solaris*) 145 146 # On Solaris (at least, for some versions), libc contains stubbed 147 # (non-functional) versions of the pthreads routines, so link-based 148 # tests will erroneously succeed. (We need to link with -pthreads/-mt/ 149 # -lpthread.) (The stubs are missing pthread_cleanup_push, or rather 150 # a function called by this macro, so we could check for that, but 151 # who knows whether they'll stub that too in a future libc.) So, 152 # we'll just look for -pthreads and -lpthread first: 153 154 acx_pthread_flags="-pthreads pthread -mt -pthread $acx_pthread_flags" 155 ;; 156esac 157 158if test x"$acx_pthread_ok" = xno; then 159for flag in $acx_pthread_flags; do 160 161 case $flag in 162 none) 163 AC_MSG_CHECKING([whether pthreads work without any flags]) 164 ;; 165 166 -*) 167 AC_MSG_CHECKING([whether pthreads work with $flag]) 168 PTHREAD_CFLAGS="$flag" 169 ;; 170 171 pthread-config) 172 AC_CHECK_PROG(acx_pthread_config, pthread-config, yes, no) 173 if test x"$acx_pthread_config" = xno; then continue; fi 174 PTHREAD_CFLAGS="`pthread-config --cflags`" 175 PTHREAD_LIBS="`pthread-config --ldflags` `pthread-config --libs`" 176 ;; 177 178 *) 179 AC_MSG_CHECKING([for the pthreads library -l$flag]) 180 PTHREAD_LIBS="-l$flag" 181 ;; 182 esac 183 184 save_LIBS="$LIBS" 185 save_CFLAGS="$CFLAGS" 186 LIBS="$PTHREAD_LIBS $LIBS" 187 CFLAGS="$CFLAGS $PTHREAD_CFLAGS" 188 189 # Check for various functions. We must include pthread.h, 190 # since some functions may be macros. (On the Sequent, we 191 # need a special flag -Kthread to make this header compile.) 192 # We check for pthread_join because it is in -lpthread on IRIX 193 # while pthread_create is in libc. We check for pthread_attr_init 194 # due to DEC craziness with -lpthreads. We check for 195 # pthread_cleanup_push because it is one of the few pthread 196 # functions on Solaris that doesn't have a non-functional libc stub. 197 # We try pthread_create on general principles. 198 AC_TRY_LINK([#include <pthread.h>], 199 [pthread_t th; pthread_join(th, 0); 200 pthread_attr_init(0); pthread_cleanup_push(0, 0); 201 pthread_create(0,0,0,0); pthread_cleanup_pop(0); ], 202 [acx_pthread_ok=yes]) 203 204 LIBS="$save_LIBS" 205 CFLAGS="$save_CFLAGS" 206 207 AC_MSG_RESULT($acx_pthread_ok) 208 if test "x$acx_pthread_ok" = xyes; then 209 break; 210 fi 211 212 PTHREAD_LIBS="" 213 PTHREAD_CFLAGS="" 214done 215fi 216 217# Various other checks: 218if test "x$acx_pthread_ok" = xyes; then 219 save_LIBS="$LIBS" 220 LIBS="$PTHREAD_LIBS $LIBS" 221 save_CFLAGS="$CFLAGS" 222 CFLAGS="$CFLAGS $PTHREAD_CFLAGS" 223 224 # Detect AIX lossage: JOINABLE attribute is called UNDETACHED. 225 AC_MSG_CHECKING([for joinable pthread attribute]) 226 attr_name=unknown 227 for attr in PTHREAD_CREATE_JOINABLE PTHREAD_CREATE_UNDETACHED; do 228 AC_TRY_LINK([#include <pthread.h>], [int attr=$attr; return attr;], 229 [attr_name=$attr; break]) 230 done 231 AC_MSG_RESULT($attr_name) 232 if test "$attr_name" != PTHREAD_CREATE_JOINABLE; then 233 AC_DEFINE_UNQUOTED(PTHREAD_CREATE_JOINABLE, $attr_name, 234 [Define to necessary symbol if this constant 235 uses a non-standard name on your system.]) 236 fi 237 238 AC_MSG_CHECKING([if more special flags are required for pthreads]) 239 flag=no 240 case "${host_cpu}-${host_os}" in 241 *-aix* | *-freebsd* | *-darwin*) flag="-D_THREAD_SAFE";; 242 *solaris* | *-osf* | *-hpux*) flag="-D_REENTRANT";; 243 esac 244 AC_MSG_RESULT(${flag}) 245 if test "x$flag" != xno; then 246 PTHREAD_CFLAGS="$flag $PTHREAD_CFLAGS" 247 fi 248 249 LIBS="$save_LIBS" 250 CFLAGS="$save_CFLAGS" 251 252 # More AIX lossage: must compile with xlc_r or cc_r 253 if test x"$GCC" != xyes; then 254 AC_CHECK_PROGS(PTHREAD_CC, xlc_r cc_r, ${CC}) 255 else 256 PTHREAD_CC=$CC 257 fi 258else 259 PTHREAD_CC="$CC" 260fi 261 262AC_SUBST(PTHREAD_LIBS) 263AC_SUBST(PTHREAD_CFLAGS) 264AC_SUBST(PTHREAD_CC) 265 266# Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND: 267if test x"$acx_pthread_ok" = xyes; then 268 ifelse([$1],,AC_DEFINE(HAVE_PTHREAD,1,[Define if you have POSIX threads libraries and header files.]),[$1]) 269 : 270else 271 acx_pthread_ok=no 272 $2 273fi 274AC_LANG_RESTORE 275])dnl ACX_PTHREAD 276