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 $ax_pthread_extra_flags" 211 212 # Check for various functions. We must include pthread.h, 213 # since some functions may be macros. (On the Sequent, we 214 # need a special flag -Kthread to make this header compile.) 215 # We check for pthread_join because it is in -lpthread on IRIX 216 # while pthread_create is in libc. We check for pthread_attr_init 217 # due to DEC craziness with -lpthreads. We check for 218 # pthread_cleanup_push because it is one of the few pthread 219 # functions on Solaris that doesn't have a non-functional libc stub. 220 # We try pthread_create on general principles. 221 AC_LINK_IFELSE([AC_LANG_PROGRAM([#include <pthread.h> 222 static void routine(void *a) { *((int*)a) = 0; } 223 static void *start_routine(void *a) { return a; }], 224 [pthread_t th; pthread_attr_t attr; 225 pthread_create(&th, 0, start_routine, 0); 226 pthread_join(th, 0); 227 pthread_attr_init(&attr); 228 pthread_cleanup_push(routine, 0); 229 pthread_cleanup_pop(0) /* ; */])], 230 [ax_pthread_ok=yes], 231 []) 232 233 LIBS="$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 333