diff --git a/sys/alpha/alpha/mem.c b/sys/alpha/alpha/mem.c
index 6a3914448ff..940d8271d62 100644
--- a/sys/alpha/alpha/mem.c
+++ b/sys/alpha/alpha/mem.c
@@ -50,6 +50,7 @@
 #include <sys/fcntl.h>
 #include <sys/kernel.h>
 #include <sys/malloc.h>
+#include <sys/memrange.h>
 #include <sys/proc.h>
 #include <sys/msgbuf.h>
 #include <sys/signalvar.h>