diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index a4ed9944407..08786335f5f 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,8 @@
+2020-03-14  Kamil Rytarowski  <n54@gmx.com>
+
+	* vax-bsd-nat.c: Define _KERNTYPES to get the declaration of
+	register_t.
+
 2020-03-13  Tom Tromey  <tom@tromey.com>
 
 	* value.h (val_print): Don't declare.
diff --git a/gdb/vax-bsd-nat.c b/gdb/vax-bsd-nat.c
index 899f3e3ed9c..652f335c1cc 100644
--- a/gdb/vax-bsd-nat.c
+++ b/gdb/vax-bsd-nat.c
@@ -17,6 +17,8 @@
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
+/* We define this to get types like register_t.  */
+#define _KERNTYPES
 #include "defs.h"
 #include "inferior.h"
 #include "regcache.h"