AC_C_PROTOTYPES
test "x$U" != "x" && AC_MSG_ERROR([Compiler not ANSI compliant])
+dnl C headers and functions.
+AC_CHECK_HEADERS([sys/sysinfo.h])
+AC_CHECK_FUNCS([get_nprocs])
+
dnl Check for basic OCaml environment and findlib.
AC_PROG_OCAML
if test "x$OCAMLC" = "xno"; then
dnl Substitute OCaml flags and packages.
AC_SUBST([OCAMLFLAGS], ["-g -safe-string -warn-error CDEFLMPSUVYZX+52-3"])
-AC_SUBST([OCAMLPACKAGES], ["-package str,unix"])
+AC_SUBST([OCAMLPACKAGES], ["-package str,unix,threads -thread"])
dnl Produce output files.
AC_CONFIG_HEADERS([config.h])