| # This was retrieved from |
| # http://svn.0pointer.de/viewvc/trunk/common/acx_pthread.m4?revision=1277&root=avahi |
| # See also (perhaps for new versions?) |
| # http://svn.0pointer.de/viewvc/trunk/common/acx_pthread.m4?root=avahi |
| # |
| # We've rewritten the inconsistency check code (from avahi), to work |
| # more broadly. In particular, it no longer assumes ld accepts -zdefs. |
| # This caused a restructing of the code, but the functionality has only |
| # changed a little. |
| |
| dnl @synopsis ACX_PTHREAD([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]]) |
| dnl |
| dnl @summary figure out how to build C programs using POSIX threads |
| dnl |
| dnl This macro figures out how to build C programs using POSIX threads. |
| dnl It sets the PTHREAD_LIBS output variable to the threads library and |
| dnl linker flags, and the PTHREAD_CFLAGS output variable to any special |
| dnl C compiler flags that are needed. (The user can also force certain |
| dnl compiler flags/libs to be tested by setting these environment |
| dnl variables.) |
| dnl |
| dnl Also sets PTHREAD_CC to any special C compiler that is needed for |
| dnl multi-threaded programs (defaults to the value of CC otherwise). |
| dnl (This is necessary on AIX to use the special cc_r compiler alias.) |
| dnl |
| dnl NOTE: You are assumed to not only compile your program with these |
| dnl flags, but also link it with them as well. e.g. you should link |
| dnl with $PTHREAD_CC $CFLAGS $PTHREAD_CFLAGS $LDFLAGS ... $PTHREAD_LIBS |
| dnl $LIBS |
| dnl |
| dnl If you are only building threads programs, you may wish to use |
| dnl these variables in your default LIBS, CFLAGS, and CC: |
| dnl |
| dnl LIBS="$PTHREAD_LIBS $LIBS" |
| dnl CFLAGS="$CFLAGS $PTHREAD_CFLAGS" |
| dnl CC="$PTHREAD_CC" |
| dnl |
| dnl In addition, if the PTHREAD_CREATE_JOINABLE thread-attribute |
| dnl constant has a nonstandard name, defines PTHREAD_CREATE_JOINABLE to |
| dnl that name (e.g. PTHREAD_CREATE_UNDETACHED on AIX). |
| dnl |
| dnl ACTION-IF-FOUND is a list of shell commands to run if a threads |
| dnl library is found, and ACTION-IF-NOT-FOUND is a list of commands to |
| dnl run it if it is not found. If ACTION-IF-FOUND is not specified, the |
| dnl default action will define HAVE_PTHREAD. |
| dnl |
| dnl Please let the authors know if this macro fails on any platform, or |
| dnl if you have any other suggestions or comments. This macro was based |
| dnl on work by SGJ on autoconf scripts for FFTW (www.fftw.org) (with |
| dnl help from M. Frigo), as well as ac_pthread and hb_pthread macros |
| dnl posted by Alejandro Forero Cuervo to the autoconf macro repository. |
| dnl We are also grateful for the helpful feedback of numerous users. |
| dnl |
| dnl @category InstalledPackages |
| dnl @author Steven G. Johnson <stevenj@alum.mit.edu> |
| dnl @version 2006-05-29 |
| dnl @license GPLWithACException |
| dnl |
| dnl Checks for GCC shared/pthread inconsistency based on work by |
| dnl Marcin Owsiany <marcin@owsiany.pl> |
| |
| |
| AC_DEFUN([ACX_PTHREAD], [ |
| AC_REQUIRE([AC_CANONICAL_HOST]) |
| AC_LANG_SAVE |
| AC_LANG_C |
| acx_pthread_ok=no |
| |
| # We used to check for pthread.h first, but this fails if pthread.h |
| # requires special compiler flags (e.g. on True64 or Sequent). |
| # It gets checked for in the link test anyway. |
| |
| # First of all, check if the user has set any of the PTHREAD_LIBS, |
| # etcetera environment variables, and if threads linking works using |
| # them: |
| if test x"$PTHREAD_LIBS$PTHREAD_CFLAGS" != x; then |
| save_CFLAGS="$CFLAGS" |
| CFLAGS="$CFLAGS $PTHREAD_CFLAGS" |
| save_LIBS="$LIBS" |
| LIBS="$PTHREAD_LIBS $LIBS" |
| AC_MSG_CHECKING([for pthread_join in LIBS=$PTHREAD_LIBS with CFLAGS=$PTHREAD_CFLAGS]) |
| AC_TRY_LINK_FUNC(pthread_join, acx_pthread_ok=yes) |
| AC_MSG_RESULT($acx_pthread_ok) |
| if test x"$acx_pthread_ok" = xno; then |
| PTHREAD_LIBS="" |
| PTHREAD_CFLAGS="" |
| fi |
| LIBS="$save_LIBS" |
| CFLAGS="$save_CFLAGS" |
| fi |
| |
| # We must check for the threads library under a number of different |
| # names; the ordering is very important because some systems |
| # (e.g. DEC) have both -lpthread and -lpthreads, where one of the |
| # libraries is broken (non-POSIX). |
| |
| # Create a list of thread flags to try. Items starting with a "-" are |
| # C compiler flags, and other items are library names, except for "none" |
| # which indicates that we try without any flags at all, and "pthread-config" |
| # which is a program returning the flags for the Pth emulation library. |
| |
| acx_pthread_flags="pthreads none -Kthread -kthread lthread -pthread -pthreads -mthreads pthread --thread-safe -mt pthread-config" |
| |
| # The ordering *is* (sometimes) important. Some notes on the |
| # individual items follow: |
| |
| # pthreads: AIX (must check this before -lpthread) |
| # none: in case threads are in libc; should be tried before -Kthread and |
| # other compiler flags to prevent continual compiler warnings |
| # -Kthread: Sequent (threads in libc, but -Kthread needed for pthread.h) |
| # -kthread: FreeBSD kernel threads (preferred to -pthread since SMP-able) |
| # lthread: LinuxThreads port on FreeBSD (also preferred to -pthread) |
| # -pthread: Linux/gcc (kernel threads), BSD/gcc (userland threads) |
| # -pthreads: Solaris/gcc |
| # -mthreads: Mingw32/gcc, Lynx/gcc |
| # -mt: Sun Workshop C (may only link SunOS threads [-lthread], but it |
| # doesn't hurt to check since this sometimes defines pthreads too; |
| # also defines -D_REENTRANT) |
| # ... -mt is also the pthreads flag for HP/aCC |
| # pthread: Linux, etcetera |
| # --thread-safe: KAI C++ |
| # pthread-config: use pthread-config program (for GNU Pth library) |
| |
| case "${host_cpu}-${host_os}" in |
| *solaris*) |
| |
| # On Solaris (at least, for some versions), libc contains stubbed |
| # (non-functional) versions of the pthreads routines, so link-based |
| # tests will erroneously succeed. (We need to link with -pthreads/-mt/ |
| # -lpthread.) (The stubs are missing pthread_cleanup_push, or rather |
| # a function called by this macro, so we could check for that, but |
| # who knows whether they'll stub that too in a future libc.) So, |
| # we'll just look for -pthreads and -lpthread first: |
| |
| acx_pthread_flags="-pthreads pthread -mt -pthread $acx_pthread_flags" |
| ;; |
| esac |
| |
| if test x"$acx_pthread_ok" = xno; then |
| for flag in $acx_pthread_flags; do |
| |
| case $flag in |
| none) |
| AC_MSG_CHECKING([whether pthreads work without any flags]) |
| ;; |
| |
| -*) |
| AC_MSG_CHECKING([whether pthreads work with $flag]) |
| PTHREAD_CFLAGS="$flag" |
| ;; |
| |
| pthread-config) |
| AC_CHECK_PROG(acx_pthread_config, pthread-config, yes, no) |
| if test x"$acx_pthread_config" = xno; then continue; fi |
| PTHREAD_CFLAGS="`pthread-config --cflags`" |
| PTHREAD_LIBS="`pthread-config --ldflags` `pthread-config --libs`" |
| ;; |
| |
| *) |
| AC_MSG_CHECKING([for the pthreads library -l$flag]) |
| PTHREAD_LIBS="-l$flag" |
| ;; |
| esac |
| |
| save_LIBS="$LIBS" |
| save_CFLAGS="$CFLAGS" |
| LIBS="$PTHREAD_LIBS $LIBS" |
| CFLAGS="$CFLAGS $PTHREAD_CFLAGS" |
| |
| # Check for various functions. We must include pthread.h, |
| # since some functions may be macros. (On the Sequent, we |
| # need a special flag -Kthread to make this header compile.) |
| # We check for pthread_join because it is in -lpthread on IRIX |
| # while pthread_create is in libc. We check for pthread_attr_init |
| # due to DEC craziness with -lpthreads. We check for |
| # pthread_cleanup_push because it is one of the few pthread |
| # functions on Solaris that doesn't have a non-functional libc stub. |
| # We try pthread_create on general principles. |
| AC_TRY_LINK([#include <pthread.h>], |
| [pthread_t th; pthread_join(th, 0); |
| pthread_attr_init(0); pthread_cleanup_push(0, 0); |
| pthread_create(0,0,0,0); pthread_cleanup_pop(0); ], |
| [acx_pthread_ok=yes]) |
| |
| LIBS="$save_LIBS" |
| CFLAGS="$save_CFLAGS" |
| |
| AC_MSG_RESULT($acx_pthread_ok) |
| if test "x$acx_pthread_ok" = xyes; then |
| break; |
| fi |
| |
| PTHREAD_LIBS="" |
| PTHREAD_CFLAGS="" |
| done |
| fi |
| |
| # Various other checks: |
| if test "x$acx_pthread_ok" = xyes; then |
| save_LIBS="$LIBS" |
| LIBS="$PTHREAD_LIBS $LIBS" |
| save_CFLAGS="$CFLAGS" |
| CFLAGS="$CFLAGS $PTHREAD_CFLAGS" |
| |
| # Detect AIX lossage: JOINABLE attribute is called UNDETACHED. |
| AC_MSG_CHECKING([for joinable pthread attribute]) |
| attr_name=unknown |
| for attr in PTHREAD_CREATE_JOINABLE PTHREAD_CREATE_UNDETACHED; do |
| AC_TRY_LINK([#include <pthread.h>], [int attr=$attr; return attr;], |
| [attr_name=$attr; break]) |
| done |
| AC_MSG_RESULT($attr_name) |
| if test "$attr_name" != PTHREAD_CREATE_JOINABLE; then |
| AC_DEFINE_UNQUOTED(PTHREAD_CREATE_JOINABLE, $attr_name, |
| [Define to necessary symbol if this constant |
| uses a non-standard name on your system.]) |
| fi |
| |
| AC_MSG_CHECKING([if more special flags are required for pthreads]) |
| flag=no |
| case "${host_cpu}-${host_os}" in |
| *-aix* | *-freebsd* | *-darwin*) flag="-D_THREAD_SAFE";; |
| *solaris* | *-osf* | *-hpux*) flag="-D_REENTRANT";; |
| esac |
| AC_MSG_RESULT(${flag}) |
| if test "x$flag" != xno; then |
| PTHREAD_CFLAGS="$flag $PTHREAD_CFLAGS" |
| fi |
| |
| LIBS="$save_LIBS" |
| CFLAGS="$save_CFLAGS" |
| # More AIX lossage: must compile with xlc_r or cc_r |
| if test x"$GCC" != xyes; then |
| AC_CHECK_PROGS(PTHREAD_CC, xlc_r cc_r, ${CC}) |
| else |
| PTHREAD_CC=$CC |
| fi |
| |
| # The next part tries to detect GCC inconsistency with -shared on some |
| # architectures and systems. The problem is that in certain |
| # configurations, when -shared is specified, GCC "forgets" to |
| # internally use various flags which are still necessary. |
| |
| # |
| # Prepare the flags |
| # |
| save_CFLAGS="$CFLAGS" |
| save_LIBS="$LIBS" |
| save_CC="$CC" |
| |
| # Try with the flags determined by the earlier checks. |
| # |
| # -Wl,-z,defs forces link-time symbol resolution, so that the |
| # linking checks with -shared actually have any value |
| # |
| # FIXME: -fPIC is required for -shared on many architectures, |
| # so we specify it here, but the right way would probably be to |
| # properly detect whether it is actually required. |
| CFLAGS="-shared -fPIC -Wl,-z,defs $CFLAGS $PTHREAD_CFLAGS" |
| LIBS="$PTHREAD_LIBS $LIBS" |
| CC="$PTHREAD_CC" |
| |
| # In order not to create several levels of indentation, we test |
| # the value of "$done" until we find the cure or run out of ideas. |
| done="no" |
| |
| # First, make sure the CFLAGS we added are actually accepted by our |
| # compiler. If not (and OS X's ld, for instance, does not accept -z), |
| # then we can't do this test. |
| if test x"$done" = xno; then |
| AC_MSG_CHECKING([whether to check for GCC pthread/shared inconsistencies]) |
| AC_TRY_LINK(,, , [done=yes]) |
| |
| if test "x$done" = xyes ; then |
| AC_MSG_RESULT([no]) |
| else |
| AC_MSG_RESULT([yes]) |
| fi |
| fi |
| |
| if test x"$done" = xno; then |
| AC_MSG_CHECKING([whether -pthread is sufficient with -shared]) |
| AC_TRY_LINK([#include <pthread.h>], |
| [pthread_t th; pthread_join(th, 0); |
| pthread_attr_init(0); pthread_cleanup_push(0, 0); |
| pthread_create(0,0,0,0); pthread_cleanup_pop(0); ], |
| [done=yes]) |
| |
| if test "x$done" = xyes; then |
| AC_MSG_RESULT([yes]) |
| else |
| AC_MSG_RESULT([no]) |
| fi |
| fi |
| |
| # |
| # Linux gcc on some architectures such as mips/mipsel forgets |
| # about -lpthread |
| # |
| if test x"$done" = xno; then |
| AC_MSG_CHECKING([whether -lpthread fixes that]) |
| LIBS="-lpthread $PTHREAD_LIBS $save_LIBS" |
| AC_TRY_LINK([#include <pthread.h>], |
| [pthread_t th; pthread_join(th, 0); |
| pthread_attr_init(0); pthread_cleanup_push(0, 0); |
| pthread_create(0,0,0,0); pthread_cleanup_pop(0); ], |
| [done=yes]) |
| |
| if test "x$done" = xyes; then |
| AC_MSG_RESULT([yes]) |
| PTHREAD_LIBS="-lpthread $PTHREAD_LIBS" |
| else |
| AC_MSG_RESULT([no]) |
| fi |
| fi |
| # |
| # FreeBSD 4.10 gcc forgets to use -lc_r instead of -lc |
| # |
| if test x"$done" = xno; then |
| AC_MSG_CHECKING([whether -lc_r fixes that]) |
| LIBS="-lc_r $PTHREAD_LIBS $save_LIBS" |
| AC_TRY_LINK([#include <pthread.h>], |
| [pthread_t th; pthread_join(th, 0); |
| pthread_attr_init(0); pthread_cleanup_push(0, 0); |
| pthread_create(0,0,0,0); pthread_cleanup_pop(0); ], |
| [done=yes]) |
| |
| if test "x$done" = xyes; then |
| AC_MSG_RESULT([yes]) |
| PTHREAD_LIBS="-lc_r $PTHREAD_LIBS" |
| else |
| AC_MSG_RESULT([no]) |
| fi |
| fi |
| if test x"$done" = xno; then |
| # OK, we have run out of ideas |
| AC_MSG_WARN([Impossible to determine how to use pthreads with shared libraries]) |
| |
| # so it's not safe to assume that we may use pthreads |
| acx_pthread_ok=no |
| fi |
| |
| CFLAGS="$save_CFLAGS" |
| LIBS="$save_LIBS" |
| CC="$save_CC" |
| else |
| PTHREAD_CC="$CC" |
| fi |
| |
| AC_SUBST(PTHREAD_LIBS) |
| AC_SUBST(PTHREAD_CFLAGS) |
| AC_SUBST(PTHREAD_CC) |
| |
| # Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND: |
| if test x"$acx_pthread_ok" = xyes; then |
| ifelse([$1],,AC_DEFINE(HAVE_PTHREAD,1,[Define if you have POSIX threads libraries and header files.]),[$1]) |
| : |
| else |
| acx_pthread_ok=no |
| $2 |
| fi |
| AC_LANG_RESTORE |
| ])dnl ACX_PTHREAD |
