diff --git a/freebsd/sys/linker_set.h b/freebsd/sys/linker_set.h
index 94b307ef..2dd056bc 100644
--- a/freebsd/sys/linker_set.h
+++ b/freebsd/sys/linker_set.h
@@ -30,7 +30,7 @@
 #ifndef _SYS_LINKER_SET_HH_
 #define _SYS_LINKER_SET_HH_
 
-#ifndef _SYS_CDEFS_HH_
+#ifndef _SYS_CDEFS_H_
 #error this file needs sys/cdefs.h as a prerequisite
 #endif
 
diff --git a/rtemsbsd/freebsd/machine/rtems-bsd-config.h.in b/rtemsbsd/freebsd/machine/rtems-bsd-config.h.in
index 926b9b20..15beb14f 100644
--- a/rtemsbsd/freebsd/machine/rtems-bsd-config.h.in
+++ b/rtemsbsd/freebsd/machine/rtems-bsd-config.h.in
@@ -31,6 +31,8 @@
 /* XXX hack so /opt.../machine/param.h can disable MSIZE and use this one */
 #define __NEW_RTEMS_BSD__
 
+#include <sys/cdefs.h>
+
 #ifndef _RTEMS_BSD_BSD_HH_
 /* General defines to activate BSD kernel parts */
 #define _KERNEL 1