===================================================================
RCS file: /cvs/mandoc/tbl_data.c,v
retrieving revision 1.6
retrieving revision 1.7
diff -u -p -r1.6 -r1.7
--- mandoc/tbl_data.c	2011/01/01 21:23:01	1.6
+++ mandoc/tbl_data.c	2011/01/01 22:27:08	1.7
@@ -1,4 +1,4 @@
-/*	$Id: tbl_data.c,v 1.6 2011/01/01 21:23:01 kristaps Exp $ */
+/*	$Id: tbl_data.c,v 1.7 2011/01/01 22:27:08 kristaps Exp $ */
 /*
  * Copyright (c) 2009, 2010 Kristaps Dzonsons <kristaps@bsd.lv>
  *
@@ -51,6 +51,9 @@ data(struct tbl *tbl, struct tbl_span *dp, 
 
 	dat = mandoc_calloc(1, sizeof(struct tbl_dat));
 	dat->layout = cp;
+
+	if (NULL == dat->layout)
+		TBL_MSG(tbl, MANDOCERR_TBLEXTRADAT, ln, *pos);
 
 	if (dp->last) {
 		dp->last->next = dat;