diff --git a/usr.sbin/rpc.yppasswdd/yppasswdd_server.c b/usr.sbin/rpc.yppasswdd/yppasswdd_server.c
index 9eb874b285a..ae5ca596405 100644
--- a/usr.sbin/rpc.yppasswdd/yppasswdd_server.c
+++ b/usr.sbin/rpc.yppasswdd/yppasswdd_server.c
@@ -103,7 +103,10 @@ copy_yp_pass(char *p, int x, int m)
 	}
 
 	t = buf;
-#define EXPAND(e)       e = t; while ((*t++ = *p++));
+#define EXPAND(e) do { \
+	e = t; \
+	while ((*t++ = *p++)); \
+} while (0)
         EXPAND(yp_password.pw_name);
 	yp_password.pw_fields |= _PWF_NAME;
         EXPAND(yp_password.pw_passwd);