1AC_DEFUN([ACX_PTHREAD], [ 2AC_REQUIRE([AC_CANONICAL_HOST]) 3AC_LANG_SAVE 4AC_LANG_C 5acx_pthread_ok=no 6 7# We used to check for pthread.h first, but this fails if pthread.h 8# requires special compiler flags (e.g. on True64 or Sequent). 9# It gets checked for in the link test anyway. 10 11# First of all, check if the user has set any of the PTHREAD_LIBS, 12# etcetera environment variables, and if threads linking works using 13# them: 14if test x"$PTHREAD_LIBS$PTHREAD_CFLAGS" != x; then 15 save_CFLAGS="$CFLAGS" 16 CFLAGS="$CFLAGS $PTHREAD_CFLAGS" 17 save_LIBS="$LIBS" 18 LIBS="$PTHREAD_LIBS $LIBS" 19 AC_MSG_CHECKING([for pthread_join in LIBS=$PTHREAD_LIBS with CFLAGS=$PTHREAD_CFLAGS]) 20 AC_TRY_LINK_FUNC(pthread_join, acx_pthread_ok=yes) 21 AC_MSG_RESULT($acx_pthread_ok) 22 if test x"$acx_pthread_ok" = xno; then 23 PTHREAD_LIBS="" 24 PTHREAD_CFLAGS="" 25 fi 26 LIBS="$save_LIBS" 27 CFLAGS="$save_CFLAGS" 28fi 29 30# We must check for the threads library under a number of different 31# names; the ordering is very important because some systems 32# (e.g. DEC) have both -lpthread and -lpthreads, where one of the 33# libraries is broken (non-POSIX). 34 35# Create a list of thread flags to try. Items starting with a "-" are 36# C compiler flags, and other items are library names, except for "none" 37# which indicates that we try without any flags at all, and "pthread-config" 38# which is a program returning the flags for the Pth emulation library. 39 40acx_pthread_flags="pthreads none -Kthread -kthread lthread -pthread -pthreads -mthreads pthread --thread-safe -mt pthread-config pthreadgc2" 41 42# The ordering *is* (sometimes) important. Some notes on the 43# individual items follow: 44 45# pthreads: AIX (must check this before -lpthread) 46# none: in case threads are in libc; should be tried before -Kthread and 47# other compiler flags to prevent continual compiler warnings 48# -Kthread: Sequent (threads in libc, but -Kthread needed for pthread.h) 49# -kthread: FreeBSD kernel threads (preferred to -pthread since SMP-able) 50# lthread: LinuxThreads port on FreeBSD (also preferred to -pthread) 51# -pthread: Linux/gcc (kernel threads), BSD/gcc (userland threads) 52# -pthreads: Solaris/gcc 53# -mthreads: Mingw32/gcc, Lynx/gcc 54# -mt: Sun Workshop C (may only link SunOS threads [-lthread], but it 55# doesn't hurt to check since this sometimes defines pthreads too; 56# also defines -D_REENTRANT) 57# pthread: Linux, etcetera 58# --thread-safe: KAI C++ 59# pthread-config: use pthread-config program (for GNU Pth library) 60 61case "${host_cpu}-${host_os}" in 62 *solaris*) 63 64 # On Solaris (at least, for some versions), libc contains stubbed 65 # (non-functional) versions of the pthreads routines, so link-based 66 # tests will erroneously succeed. (We need to link with -pthread or 67 # -lpthread.) (The stubs are missing pthread_cleanup_push, or rather 68 # a function called by this macro, so we could check for that, but 69 # who knows whether they'll stub that too in a future libc.) So, 70 # we'll just look for -pthreads and -lpthread first: 71 72 acx_pthread_flags="-pthread -pthreads pthread -mt $acx_pthread_flags" 73 ;; 74 *cygwin*) 75 acx_pthread_flags="-lpthread $acx_pthread_flags" 76 ;; 77 *freebsd*) 78 # freebsd 4 uses -pthread, freebsd 5 and above use -lpthread 79 acx_pthread_flags="pthread -pthread" 80esac 81 82if test x"$acx_pthread_ok" = xno; then 83for flag in $acx_pthread_flags; do 84 85 case $flag in 86 none) 87 AC_MSG_CHECKING([whether pthreads work without any flags]) 88 ;; 89 90 -*) 91 AC_MSG_CHECKING([whether pthreads work with $flag]) 92 PTHREAD_CFLAGS="$flag" 93 ;; 94 95 pthread-config) 96 AC_CHECK_PROG(acx_pthread_config, pthread-config, yes, no) 97 if test x"$acx_pthread_config" = xno; then continue; fi 98 PTHREAD_CFLAGS="`pthread-config --cflags`" 99 PTHREAD_LIBS="`pthread-config --ldflags` `pthread-config --libs`" 100 ;; 101 102 *) 103 AC_MSG_CHECKING([for the pthreads library -l$flag]) 104 PTHREAD_LIBS="-l$flag" 105 ;; 106 esac 107 108 save_LIBS="$LIBS" 109 save_CFLAGS="$CFLAGS" 110 LIBS="$PTHREAD_LIBS $LIBS" 111 CFLAGS="$CFLAGS $PTHREAD_CFLAGS" 112 113 # Check for various functions. We must include pthread.h, 114 # since some functions may be macros. (On the Sequent, we 115 # need a special flag -Kthread to make this header compile.) 116 # We check for pthread_join because it is in -lpthread on IRIX 117 # while pthread_create is in libc. We check for pthread_attr_init 118 # due to DEC craziness with -lpthreads. We check for 119 # pthread_cleanup_push because it is one of the few pthread 120 # functions on Solaris that doesn't have a non-functional libc stub. 121 # We try pthread_create on general principles. 122 AC_TRY_LINK([#include <pthread.h>], 123 [pthread_t th; pthread_join(th, 0); 124 pthread_attr_init(0); pthread_cleanup_push(0, 0); 125 pthread_create(0,0,0,0); pthread_cleanup_pop(0); ], 126 [acx_pthread_ok=yes]) 127 128 LIBS="$save_LIBS" 129 CFLAGS="$save_CFLAGS" 130 131 AC_MSG_RESULT($acx_pthread_ok) 132 if test "x$acx_pthread_ok" = xyes; then 133 break; 134 fi 135 136 PTHREAD_LIBS="" 137 PTHREAD_CFLAGS="" 138done 139fi 140 141# Various other checks: 142if test "x$acx_pthread_ok" = xyes; then 143 save_LIBS="$LIBS" 144 LIBS="$PTHREAD_LIBS $LIBS" 145 save_CFLAGS="$CFLAGS" 146 CFLAGS="$CFLAGS $PTHREAD_CFLAGS" 147 148 # Detect AIX lossage: JOINABLE attribute is called UNDETACHED. 149 AC_MSG_CHECKING([for joinable pthread attribute]) 150 attr_name=unknown 151 for attr in PTHREAD_CREATE_JOINABLE PTHREAD_CREATE_UNDETACHED; do 152 AC_TRY_LINK([#include <pthread.h>], [int attr=$attr;], 153 [attr_name=$attr; break]) 154 done 155 AC_MSG_RESULT($attr_name) 156 if test "$attr_name" != PTHREAD_CREATE_JOINABLE; then 157 AC_DEFINE_UNQUOTED(PTHREAD_CREATE_JOINABLE, $attr_name, 158 [Define to necessary symbol if this constant 159 uses a non-standard name on your system.]) 160 fi 161 162 AC_MSG_CHECKING([if more special flags are required for pthreads]) 163 flag=no 164 case "${host_cpu}-${host_os}" in 165 *-aix* | *-freebsd* | *-darwin*) flag="-D_THREAD_SAFE";; 166 *solaris* | *-osf* | *-hpux*) flag="-D_REENTRANT";; 167 esac 168 AC_MSG_RESULT(${flag}) 169 if test "x$flag" != xno; then 170 PTHREAD_CFLAGS="$flag $PTHREAD_CFLAGS" 171 fi 172 173 LIBS="$save_LIBS" 174 CFLAGS="$save_CFLAGS" 175 176 # More AIX lossage: must compile with cc_r 177 AC_CHECK_PROG(PTHREAD_CC, cc_r, cc_r, ${CC}) 178else 179 PTHREAD_CC="$CC" 180fi 181 182AC_SUBST(PTHREAD_LIBS) 183AC_SUBST(PTHREAD_CFLAGS) 184AC_SUBST(PTHREAD_CC) 185 186# Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND: 187if test x"$acx_pthread_ok" = xyes; then 188 ifelse([$1],,AC_DEFINE(HAVE_PTHREAD,1,[Define if you have POSIX threads libraries and header files.]),[$1]) 189 : 190else 191 acx_pthread_ok=no 192 $2 193fi 194AC_LANG_RESTORE 195])dnl ACX_PTHREAD 196 197