diff --git a/usr.sbin/installboot/install_master.c b/usr.sbin/installboot/install_master.c
index 706f2255e..c86130cbf 100644
--- a/usr.sbin/installboot/install_master.c
+++ b/usr.sbin/installboot/install_master.c
@@ -3,6 +3,10 @@
  *	installboot 3.0 - Make a device bootable	Author: Kees J. Bot
  *								21 Dec 1991
  */
+#if HAVE_NBTOOL_CONFIG_H
+#include "nbtool_config.h"
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
diff --git a/usr.sbin/installboot/minixfs3.c b/usr.sbin/installboot/minixfs3.c
index e26c1e68f..f590c0cef 100644
--- a/usr.sbin/installboot/minixfs3.c
+++ b/usr.sbin/installboot/minixfs3.c
@@ -1,3 +1,7 @@
+#if HAVE_NBTOOL_CONFIG_H
+#include "nbtool_config.h"
+#endif
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdint.h>