diff options
Diffstat (limited to 'acinclude.m4')
| -rw-r--r-- | acinclude.m4 | 217 |
1 files changed, 177 insertions, 40 deletions
diff --git a/acinclude.m4 b/acinclude.m4 index f3a4ac52..723eb87e 100644 --- a/acinclude.m4 +++ b/acinclude.m4 @@ -1,6 +1,55 @@ -dnl Available from the GNU Autoconf Macro Archive at: -dnl http://www.gnu.org/software/ac-archive/htmldoc/acx_pthread.html +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 @@ -57,6 +106,7 @@ acx_pthread_flags="pthreads none -Kthread -kthread lthread -pthread -pthreads -m # -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) @@ -66,13 +116,13 @@ case "${host_cpu}-${host_os}" in # 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 -pthread or + # 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="-pthread -pthreads pthread -mt $acx_pthread_flags" + acx_pthread_flags="-pthreads pthread -mt -pthread $acx_pthread_flags" ;; esac @@ -142,54 +192,142 @@ if test "x$acx_pthread_ok" = xyes; then save_CFLAGS="$CFLAGS" CFLAGS="$CFLAGS $PTHREAD_CFLAGS" - # Detect AIX lossage: threads are created detached by default - # and the JOINABLE attribute has a nonstandard name (UNDETACHED). - AC_MSG_CHECKING([for joinable pthread attribute]) - AC_TRY_LINK([#include <pthread.h>], - [int attr=PTHREAD_CREATE_JOINABLE;], - ok=PTHREAD_CREATE_JOINABLE, ok=unknown) - if test x"$ok" = xunknown; then - AC_TRY_LINK([#include <pthread.h>], - [int attr=PTHREAD_CREATE_UNDETACHED;], - ok=PTHREAD_CREATE_UNDETACHED, ok=unknown) - fi - if test x"$ok" != xPTHREAD_CREATE_JOINABLE; then - AC_DEFINE(PTHREAD_CREATE_JOINABLE, $ok, - [Define to the necessary symbol if this constant - uses a non-standard name on your system.]) - fi - AC_MSG_RESULT(${ok}) - if test x"$ok" = xunknown; then - AC_MSG_WARN([we do not know how to create joinable pthreads]) + # Detect AIX lossage: JOINABLE attribute is called UNDETACHED. + AC_MSG_CHECKING([for joinable pthread attribute]) + attr_name=unknown + for attr in PTHREAD_CREATE_JOINABLE PTHREAD_CREATE_UNDETACHED; do + AC_TRY_LINK([#include <pthread.h>], [int attr=$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}-${host_os}" in - *-aix* | *-freebsd* | *-darwin*) flag="-D_THREAD_SAFE";; - *solaris* | *-osf* | *-hpux*) flag="-D_REENTRANT";; + *-aix* | *-freebsd* | *-darwin*) flag="-D_THREAD_SAFE";; + *solaris* | *-osf* | *-hpux*) flag="-D_REENTRANT";; esac AC_MSG_RESULT(${flag}) if test "x$flag" != xno; then - PTHREAD_CFLAGS="$flag $PTHREAD_CFLAGS" - fi - - AC_MSG_CHECKING([if pthread_yield is available]) - flag=no - AC_TRY_LINK([#include <pthread.h>], - [pthread_yield();], - [flag=yes]) - AC_MSG_RESULT(${flag}) - if test "x$flag" != xno; then - AC_DEFINE(HAVE_PTHREAD_YIELD, 1, - [Define to 1 if you have the 'pthread_yield' function.]) + PTHREAD_CFLAGS="$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 - # More AIX lossage: must compile with cc_r - AC_CHECK_PROG(PTHREAD_CC, cc_r, cc_r, ${CC}) + # The next part tries to detect GCC inconsistency with -shared on some + # architectures and systems. The problem is that in certain + # configurations, when -shared is specified, GCC "forgets" to + # internally use various flags which are still necessary. + + AC_MSG_CHECKING([whether to check for GCC pthread/shared inconsistencies]) + check_inconsistencies=yes + case "${host_cpu}-${host_os}" in + *-darwin*) check_inconsistencies=no ;; + esac + if test x"$GCC" != xyes -o "x$check_inconsistencies" != xyes ; then + AC_MSG_RESULT([no]) + else + AC_MSG_RESULT([yes]) + + # In order not to create several levels of indentation, we test + # the value of "$ok" until we find out the cure or run out of + # ideas. + ok="no" + + # + # 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" + + 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); ], + [ok=yes]) + + if test "x$ok" = xyes; then + AC_MSG_RESULT([yes]) + else + AC_MSG_RESULT([no]) + fi + + # + # Linux gcc on some architectures such as mips/mipsel forgets + # about -lpthread + # + if test x"$ok" = xno; then + AC_MSG_CHECKING([whether -lpthread fixes that]) + LIBS="-lpthread $PTHREAD_LIBS $save_LIBS" + AC_TRY_LINK([#include <pthread.h>], + [pthread_t th; pthread_join(th, 0); + pthread_attr_init(0); pthread_cleanup_push(0, 0); + pthread_create(0,0,0,0); pthread_cleanup_pop(0); ], + [ok=yes]) + + if test "x$ok" = xyes; then + AC_MSG_RESULT([yes]) + PTHREAD_LIBS="-lpthread $PTHREAD_LIBS" + else + AC_MSG_RESULT([no]) + fi + fi + # + # FreeBSD 4.10 gcc forgets to use -lc_r instead of -lc + # + if test x"$ok" = xno; then + AC_MSG_CHECKING([whether -lc_r fixes that]) + LIBS="-lc_r $PTHREAD_LIBS $save_LIBS" + AC_TRY_LINK([#include <pthread.h>], + [pthread_t th; pthread_join(th, 0); + pthread_attr_init(0); pthread_cleanup_push(0, 0); + pthread_create(0,0,0,0); pthread_cleanup_pop(0); ], + [ok=yes]) + + if test "x$ok" = xyes; then + AC_MSG_RESULT([yes]) + PTHREAD_LIBS="-lc_r $PTHREAD_LIBS" + else + AC_MSG_RESULT([no]) + fi + fi + if test x"$ok" = 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="$save_CC" + fi else PTHREAD_CC="$CC" fi @@ -208,7 +346,6 @@ else fi AC_LANG_RESTORE ])dnl ACX_PTHREAD - AC_DEFUN([AC_CHECK_DEFINE],[ AS_VAR_PUSHDEF([ac_var],[ac_cv_defined_$1_$2])dnl AC_CACHE_CHECK([for $1 in $2], ac_var, |