diff --git a/libxo/xo_syslog.c b/libxo/xo_syslog.c
index 62da1811..4a16c3a5 100644
--- a/libxo/xo_syslog.c
+++ b/libxo/xo_syslog.c
@@ -58,7 +58,9 @@
 #include <stdarg.h>
 #include <sys/time.h>
 #include <sys/types.h>
+#ifdef HAVE_SYS_SYSCTL
 #include <sys/sysctl.h>
+#endif
 
 #include "xo_config.h"
 #include "xo.h"