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