diff --git a/src/option.h b/src/option.h
index 167b562..737cbca 100644
--- a/src/option.h
+++ b/src/option.h
@@ -1031,6 +1031,7 @@
     , BV_TW
     , BV_TX
     , BV_UDF
+    , BV_UL
     , BV_WM
     , BV_COUNT	    /* must be the last one */
 };
@@ -1109,3 +1110,6 @@
     , WV_WRAP
     , WV_COUNT	    /* must be the last one */
 };
+
+/* Value for b_p_ul indicating the global value must be used. */
+#define NO_LOCAL_UNDOLEVEL -123456