# =========================================================================== # http://www.gnu.org/software/autoconf-archive/ax_pthread.html # =========================================================================== # # SYNOPSIS # # AX_PTHREAD([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]]) # # DESCRIPTION # # This macro figures out how to build C programs using POSIX threads. It # sets the PTHREAD_LIBS output variable to the threads library and linker # flags, and the PTHREAD_CFLAGS output variable to any special C compiler # flags that are needed. (The user can also force certain compiler # flags/libs to be tested by setting these environment variables.) # # Also sets PTHREAD_CC to any special C compiler that is needed for # multi-threaded programs (defaults to the value of CC otherwise). (This # is necessary on AIX to use the special cc_r compiler alias.) # # NOTE: You are assumed to not only compile your program with these flags, # but also link it with them as well. e.g. you should link with # $PTHREAD_CC $CFLAGS $PTHREAD_CFLAGS $LDFLAGS ... $PTHREAD_LIBS $LIBS # # If you are only building threads programs, you may wish to use these # variables in your default LIBS, CFLAGS, and CC: # # LIBS="$PTHREAD_LIBS $LIBS" # CFLAGS="$CFLAGS $PTHREAD_CFLAGS" # CC="$PTHREAD_CC" # # In addition, if the PTHREAD_CREATE_JOINABLE thread-attribute constant # has a nonstandard name, defines PTHREAD_CREATE_JOINABLE to that name # (e.g. PTHREAD_CREATE_UNDETACHED on AIX). # # Also HAVE_PTHREAD_PRIO_INHERIT is defined if pthread is found and the # PTHREAD_PRIO_INHERIT symbol is defined when compiling with # PTHREAD_CFLAGS. # # ACTION-IF-FOUND is a list of shell commands to run if a threads library # is found, and ACTION-IF-NOT-FOUND is a list of commands to run it if it # is not found. If ACTION-IF-FOUND is not specified, the default action # will define HAVE_PTHREAD. # # Please let the authors know if this macro fails on any platform, or if # you have any other suggestions or comments. This macro was based on work # by SGJ on autoconf scripts for FFTW (http://www.fftw.org/) (with help # from M. Frigo), as well as ac_pthread and hb_pthread macros posted by # Alejandro Forero Cuervo to the autoconf macro repository. We are also # grateful for the helpful feedback of numerous users. # # Updated for Autoconf 2.68 by Daniel Richard G. # # LICENSE # # Copyright (c) 2008 Steven G. Johnson # Copyright (c) 2011 Daniel Richard G. # # This program is free software: you can redistribute it and/or modify it # under the terms of the GNU General Public License as published by the # Free Software Foundation, either version 3 of the License, or (at your # option) any later version. # # This program is distributed in the hope that it will be useful, but # WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General # Public License for more details. # # You should have received a copy of the GNU General Public License along # with this program. If not, see . # # As a special exception, the respective Autoconf Macro's copyright owner # gives unlimited permission to copy, distribute and modify the configure # scripts that are the output of Autoconf when processing the Macro. You # need not follow the terms of the GNU General Public License when using # or distributing such scripts, even though portions of the text of the # Macro appear in them. The GNU General Public License (GPL) does govern # all other use of the material that constitutes the Autoconf Macro. # # This special exception to the GPL applies to versions of the Autoconf # Macro released by the Autoconf Archive. When you make and distribute a # modified version of the Autoconf Macro, you may extend this special # exception to the GPL to apply to your modified version as well. #serial 21 AU_ALIAS([ACX_PTHREAD], [AX_PTHREAD]) AC_DEFUN([AX_PTHREAD], [ AC_REQUIRE([AC_CANONICAL_HOST]) AC_LANG_PUSH([C]) ax_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=$PTHREAD_CFLAGS]) AC_TRY_LINK_FUNC([pthread_join], [ax_pthread_ok=yes]) AC_MSG_RESULT([$ax_pthread_ok]) if test x"$ax_pthread_ok" = xno; then PTHREAD_LIBS="" PTHREAD_CFLAGS="" fi LIBS="$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. ax_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_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: ax_pthread_flags="-pthreads pthread -mt -pthread $ax_pthread_flags" ;; darwin*) ax_pthread_flags="-pthread $ax_pthread_flags" ;; esac # Clang doesn't consider unrecognized options an error unless we specify # -Werror. We throw in some extra Clang-specific options to ensure that # this doesn't happen for GCC, which also accepts -Werror. AC_MSG_CHECKING([if compiler needs -Werror to reject unknown flags]) save_CFLAGS="$CFLAGS" ax_pthread_extra_flags="-Werror" CFLAGS="$CFLAGS $ax_pthread_extra_flags -Wunknown-warning-option -Wsizeof-array-argument" AC_COMPILE_IFELSE([AC_LANG_PROGRAM([int foo(void);],[foo()])], [AC_MSG_RESULT([yes])], [ax_pthread_extra_flags= AC_MSG_RESULT([no])]) CFLAGS="$save_CFLAGS" if test x"$ax_pthread_ok" = xno; then for flag in $ax_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([ax_pthread_config], [pthread-config], [yes], [no]) if test x"$ax_pthread_config" = xno; then continue; fi PTHREAD_CFLAGS="`pthread-config --cflags`" PTHREAD_LIBS="`pthread-config --ldflags` `pthread-config --libs`" ;; *) AC_MSG_CHECKING([for the pthreads library -l$flag]) PTHREAD_LIBS="-l$flag" ;; esac save_LIBS="$LIBS" save_CFLAGS="$CFLAGS" LIBS="$PTHREAD_LIBS $LIBS" CFLAGS="$CFLAGS $PTHREAD_CFLAGS $ax_pthread_extra_flags" # Check for various functions. We must include pthread.h, # since some functions may be macros. (On the Sequent, we # need a special flag -Kthread to make this header compile.) # We check for pthread_join because it is in -lpthread on IRIX # while pthread_create is in libc. We check for pthread_attr_init # due to DEC craziness with -lpthreads. We check for # pthread_cleanup_push because it is one of the few pthread # functions on Solaris that doesn't have a non-functional libc stub. # We try pthread_create on general principles. AC_LINK_IFELSE([AC_LANG_PROGRAM([#include static void routine(void *a) { a = 0; } static void *start_routine(void *a) { return a; }], [pthread_t th; pthread_attr_t attr; pthread_create(&th, 0, start_routine, 0); pthread_join(th, 0); pthread_attr_init(&attr); pthread_cleanup_push(routine, 0); pthread_cleanup_pop(0) /* ; */])], [ax_pthread_ok=yes], []) LIBS="$save_LIBS" CFLAGS="$save_CFLAGS" AC_MSG_RESULT([$ax_pthread_ok]) if test "x$ax_pthread_ok" = xyes; then break; fi PTHREAD_LIBS="" PTHREAD_CFLAGS="" done fi # Various other checks: if test "x$ax_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_LINK_IFELSE([AC_LANG_PROGRAM([#include ], [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 ${host_os} in aix* | freebsd* | darwin*) flag="-D_THREAD_SAFE";; osf* | hpux*) flag="-D_REENTRANT";; solaris*) if test "$GCC" = "yes"; then flag="-D_REENTRANT" else # TODO: What about Clang on Solaris? flag="-mt -D_REENTRANT" fi ;; esac AC_MSG_RESULT([$flag]) if test "x$flag" != xno; then PTHREAD_CFLAGS="$flag $PTHREAD_CFLAGS" fi AC_CACHE_CHECK([for PTHREAD_PRIO_INHERIT], [ax_cv_PTHREAD_PRIO_INHERIT], [ AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include ]], [[int i = PTHREAD_PRIO_INHERIT;]])], [ax_cv_PTHREAD_PRIO_INHERIT=yes], [ax_cv_PTHREAD_PRIO_INHERIT=no]) ]) AS_IF([test "x$ax_cv_PTHREAD_PRIO_INHERIT" = "xyes"], [AC_DEFINE([HAVE_PTHREAD_PRIO_INHERIT], [1], [Have PTHREAD_PRIO_INHERIT.])]) LIBS="$save_LIBS" CFLAGS="$save_CFLAGS" # More AIX lossage: compile with *_r variant if test "x$GCC" != xyes; then case $host_os in aix*) AS_CASE(["x/$CC"], [x*/c89|x*/c89_128|x*/c99|x*/c99_128|x*/cc|x*/cc128|x*/xlc|x*/xlc_v6|x*/xlc128|x*/xlc128_v6], [#handle absolute path differently from PATH based program lookup AS_CASE(["x$CC"], [x/*], [AS_IF([AS_EXECUTABLE_P([${CC}_r])],[PTHREAD_CC="${CC}_r"])], [AC_CHECK_PROGS([PTHREAD_CC],[${CC}_r],[$CC])])]) ;; esac fi fi test -n "$PTHREAD_CC" || PTHREAD_CC="$CC" AC_SUBST([PTHREAD_LIBS]) AC_SUBST([PTHREAD_CFLAGS]) AC_SUBST([PTHREAD_CC]) # Finally, execute ACTION-IF-FOUND/ACTION-IF-NOT-FOUND: if test x"$ax_pthread_ok" = xyes; then ifelse([$1],,[AC_DEFINE([HAVE_PTHREAD],[1],[Define if you have POSIX threads libraries and header files.])],[$1]) : else ax_pthread_ok=no $2 fi AC_LANG_POP ])dnl AX_PTHREAD