+#if (defined(__linux__) && defined(__NR_futex))
+
+/* For backwards compat */
+#define CONFIG_RCU_HAVE_FUTEX 1
+
+#include <unistd.h>
+#include <errno.h>
+#include <urcu/compiler.h>
+#include <urcu/arch.h>
+
+#elif defined(__FreeBSD__)
+
+#include <sys/types.h>
+#include <sys/umtx.h>
+
+#endif
+