dnl file : m4/threads.m4 dnl author : Boris Kolpackov <boris@codesynthesis.com> dnl copyright : Copyright (c) 2009-2011 Code Synthesis Tools CC dnl license : GNU GPL v2; see accompanying LICENSE file dnl AC_DEFUN([THREADS],[ threads_thread_keyword=no AC_ARG_ENABLE( [threads], AS_HELP_STRING([--disable-threads], [disable threads (enabled by default)]), [AS_IF([test x"$enableval" = xno], [threads=none], [threads=check])], [threads=check]) # If thread support is not disabled by the user, figure out what we can use. # if test x$threads = xcheck; then case $host_os in windows* | mingw*) case $host_os in mingw*) CXXFLAGS="$CXXFLAGS -mthreads" ;; esac threads=win32 ;; *) ACX_PTHREAD if test x$acx_pthread_ok = xyes; then threads=posix LIBS="$LIBS $PTHREAD_LIBS" CXXFLAGS="$CXXFLAGS $PTHREAD_CXXFLAGS" # Check if we can use the __thread keyword. # AC_MSG_CHECKING([for __thread keyword]) CXX_LIBTOOL_LINK_IFELSE( AC_LANG_SOURCE([[ __thread int tls_var; int main () { tls_var = 0; } ]]), [threads_thread_keyword=yes]) AC_MSG_RESULT([$threads_thread_keyword]) fi ;; esac fi if test x$threads = xcheck; then AC_MSG_ERROR([thread support not available; use --disable-threads to force single-threaded mode]) fi ])dnl