+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h. */
+#include <semaphore.h>
+int
+main ()
+{
+sem_t *s; const struct timespec * t; sem_timedwait(s, t);
+ ;
+ return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext
+if { (ac_try="$ac_compile"
+case "(($ac_try" in
+ *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+ *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+ (eval "$ac_compile") 2>conftest.er1
+ ac_status=$?
+ grep -v '^ *+' conftest.er1 >conftest.err
+ rm -f conftest.er1
+ cat conftest.err >&5
+ echo "$as_me:$LINENO: \$? = $ac_status" >&5
+ (exit $ac_status); } && {
+ test -z "$ac_c_werror_flag" ||
+ test ! -s conftest.err
+ } && test -s conftest.$ac_objext; then
+ HAVE_SEM_TIMEDWAIT=yes
+else
+ echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+ HAVE_SEM_TIMEDWAIT=no
+fi
+
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+ if test ${HAVE_SEM_TIMEDWAIT} = yes ; then
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_SEM_TIMEDWAIT 1
+_ACEOF
+
+ { echo "$as_me:$LINENO: result: yes" >&5
+echo "${ECHO_T}yes" >&6; }
+ else
+ { echo "$as_me:$LINENO: result: no" >&5
+echo "${ECHO_T}no" >&6; }
+ fi
+ fi
+
+ { echo "$as_me:$LINENO: checking for pthread_mutex_timedlock in -lpthread" >&5
+echo $ECHO_N "checking for pthread_mutex_timedlock in -lpthread... $ECHO_C" >&6; }
+if test "${ac_cv_lib_pthread_pthread_mutex_timedlock+set}" = set; then
+ echo $ECHO_N "(cached) $ECHO_C" >&6
+else
+ ac_check_lib_save_LIBS=$LIBS
+LIBS="-lpthread $LIBS"
+cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h. */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h. */
+
+/* Override any GCC internal prototype to avoid an error.
+ Use char because int might match the return type of a GCC
+ builtin and then its argument prototype would still apply. */
+#ifdef __cplusplus
+extern "C"
+#endif
+char pthread_mutex_timedlock ();
+int
+main ()
+{
+return pthread_mutex_timedlock ();
+ ;
+ return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext conftest$ac_exeext
+if { (ac_try="$ac_link"
+case "(($ac_try" in
+ *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+ *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+ (eval "$ac_link") 2>conftest.er1
+ ac_status=$?
+ grep -v '^ *+' conftest.er1 >conftest.err
+ rm -f conftest.er1
+ cat conftest.err >&5
+ echo "$as_me:$LINENO: \$? = $ac_status" >&5
+ (exit $ac_status); } && {
+ test -z "$ac_c_werror_flag" ||
+ test ! -s conftest.err
+ } && test -s conftest$ac_exeext &&
+ $as_test_x conftest$ac_exeext; then
+ ac_cv_lib_pthread_pthread_mutex_timedlock=yes
+else
+ echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+ ac_cv_lib_pthread_pthread_mutex_timedlock=no
+fi
+
+rm -f core conftest.err conftest.$ac_objext conftest_ipa8_conftest.oo \
+ conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+{ echo "$as_me:$LINENO: result: $ac_cv_lib_pthread_pthread_mutex_timedlock" >&5
+echo "${ECHO_T}$ac_cv_lib_pthread_pthread_mutex_timedlock" >&6; }
+if test $ac_cv_lib_pthread_pthread_mutex_timedlock = yes; then
+ HAVE_MUTEX_TIMEDLOCK=yes
+else
+ HAVE_MUTEX_TIMEDLOCK=no
+fi
+
+ if test ${HAVE_MUTEX_TIMEDLOCK} = yes ; then
+ { echo "$as_me:$LINENO: checking if pthread_mutex_timedlock is compilable" >&5
+echo $ECHO_N "checking if pthread_mutex_timedlock is compilable... $ECHO_C" >&6; }
+ cat >conftest.$ac_ext <<_ACEOF
+/* confdefs.h. */
+_ACEOF
+cat confdefs.h >>conftest.$ac_ext
+cat >>conftest.$ac_ext <<_ACEOF
+/* end confdefs.h. */
+#include <pthread.h>
+int
+main ()
+{
+pthread_mutex_t s; const struct timespec t; sem_timedlock(&s, &t);
+ ;
+ return 0;
+}
+_ACEOF
+rm -f conftest.$ac_objext
+if { (ac_try="$ac_compile"
+case "(($ac_try" in
+ *\"* | *\`* | *\\*) ac_try_echo=\$ac_try;;
+ *) ac_try_echo=$ac_try;;
+esac
+eval "echo \"\$as_me:$LINENO: $ac_try_echo\"") >&5
+ (eval "$ac_compile") 2>conftest.er1
+ ac_status=$?
+ grep -v '^ *+' conftest.er1 >conftest.err
+ rm -f conftest.er1
+ cat conftest.err >&5
+ echo "$as_me:$LINENO: \$? = $ac_status" >&5
+ (exit $ac_status); } && {
+ test -z "$ac_c_werror_flag" ||
+ test ! -s conftest.err
+ } && test -s conftest.$ac_objext; then
+ HAVE_MUTEX_TIMEDLOCK=yes
+else
+ echo "$as_me: failed program was:" >&5
+sed 's/^/| /' conftest.$ac_ext >&5
+
+ HAVE_MUTEX_TIMEDLOCK=no
+fi
+
+rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
+ if test ${HAVE_MUTEX_TIMEDLOCK} = yes ; then
+
+cat >>confdefs.h <<\_ACEOF
+#define HAVE_MUTEX_TIMEDLOCK 1
+_ACEOF
+
+ { echo "$as_me:$LINENO: result: yes" >&5
+echo "${ECHO_T}yes" >&6; }
+ else
+ { echo "$as_me:$LINENO: result: no" >&5
+echo "${ECHO_T}no" >&6; }
+ fi
+ fi
+fi
+
+
+if test ".$mcsc" = .yes; then
+ # ucontext found
+ mcsc=yes
+elif test ".$pthread" = .yes; then
+ # ucontext not found, but pthread found
+ pthread=yes
+else
+ ac_header=windows.h
+ as_ac_Header=`echo "ac_cv_header_$ac_header" | $as_tr_sh`
+ if test `eval echo '${'$as_ac_Header'}'` = yes; then
+ windows_context=yes
+ else
+ { { echo "$as_me:$LINENO: error: no appropriate backend found" >&5
+echo "$as_me: error: no appropriate backend found" >&2;}
+ { (exit 1); exit 1; }; }
+ fi
+fi
+ if test x$windows_context = xyes; then
+ IS_WINDOWS_TRUE=
+ IS_WINDOWS_FALSE='#'
+else
+ IS_WINDOWS_TRUE='#'
+ IS_WINDOWS_FALSE=
+fi
+
+
+
+
+{ echo "$as_me:$LINENO: checking what kind of backend should we use" >&5
+echo $ECHO_N "checking what kind of backend should we use... $ECHO_C" >&6; }
+
+
+# Check whether --with-pthread was given.
+if test "${with_pthread+set}" = set; then
+ withval=$with_pthread; with_context=pthread
+fi
+
+
+# Check whether --with-pthread was given.
+if test "${with_pthread+set}" = set; then
+ withval=$with_pthread; with_context=pthread
+fi
+
+
+
+# Check whether --with-context was given.
+if test "${with_context+set}" = set; then
+ withval=$with_context;
+else
+ with_context=auto
+fi
+
+
+if test "x$with_context$mcsc" = "xucontextno" ; then
+ { { echo "$as_me:$LINENO: error: --with-context=ucontext specified but ucontext unusable. Relaunch configure without this argument." >&5
+echo "$as_me: error: --with-context=ucontext specified but ucontext unusable. Relaunch configure without this argument." >&2;}
+ { (exit 77); exit 77; }; }
+fi
+
+case $with_context in
+ ucontext) ;;
+ pthread) ;;
+ pthreads) ;;
+ windows) ;;
+ auto) with_context=ucontext;;
+ *) { { echo "$as_me:$LINENO: error: --with-context must be either ucontext or pthread" >&5
+echo "$as_me: error: --with-context must be either ucontext or pthread" >&2;}
+ { (exit 1); exit 1; }; } ;;
+esac
+
+if test "x$with_context" = "xucontext" ; then
+ if test ".$mcsc" = .yes; then
+ { echo "$as_me:$LINENO: result: found working ucontext. Great!" >&5
+echo "${ECHO_T}found working ucontext. Great!" >&6; }
+
+cat >>confdefs.h <<\_ACEOF
+#define CONTEXT_UCONTEXT 1
+_ACEOF
+
+ else
+ if test ".$windows_context" = .yes ; then
+ { echo "$as_me:$LINENO: result: use windows context portability layer." >&5
+echo "${ECHO_T}use windows context portability layer." >&6; }
+ with_context=windows
+ else
+ { echo "$as_me:$LINENO: result: no working ucontext found. Try pthreads as a fallback" >&5
+echo "${ECHO_T}no working ucontext found. Try pthreads as a fallback" >&6; }
+ with_context=pthread
+ fi
+ fi
+fi
+
+if test "x$with_context" = "xpthread"; then
+ if test x$pthread != xyes ; then # reuse previous checks
+ { { echo "$as_me:$LINENO: error: Cannot find pthreads (try --with-context=ucontext if you haven't already tried)." >&5
+echo "$as_me: error: Cannot find pthreads (try --with-context=ucontext if you haven't already tried)." >&2;}
+ { (exit 1); exit 1; }; }
+ fi
+
+cat >>confdefs.h <<\_ACEOF
+#define CONTEXT_THREADS 1
+_ACEOF
+