diff --git a/Quake/sys_sdl_unix.c b/Quake/sys_sdl_unix.c
index dfbe31de..b90ec5ac 100644
--- a/Quake/sys_sdl_unix.c
+++ b/Quake/sys_sdl_unix.c
@@ -20,6 +20,7 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 */
 
+#include "arch_def.h"
 #include "quakedef.h"
 
 #include <sys/types.h>