===================================================================
RCS file: /cvs/mandoc/main.c,v
retrieving revision 1.273.2.4
retrieving revision 1.273.2.5
diff -u -p -r1.273.2.4 -r1.273.2.5
--- mandoc/main.c	2017/01/09 17:57:15	1.273.2.4
+++ mandoc/main.c	2017/01/27 14:41:40	1.273.2.5
@@ -1,4 +1,4 @@
-/*	$Id: main.c,v 1.273.2.4 2017/01/09 17:57:15 schwarze Exp $ */
+/*	$Id: main.c,v 1.273.2.5 2017/01/27 14:41:40 schwarze Exp $ */
 /*
  * Copyright (c) 2008-2012 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010-2012, 2014-2017 Ingo Schwarze <schwarze@openbsd.org>
@@ -125,6 +125,7 @@ main(int argc, char *argv[])
 	struct manpage	*res, *resp;
 	char		*conf_file, *defpaths;
 	const char	*sec;
+	const char	*thisarg;
 	size_t		 i, sz;
 	int		 prio, best_prio;
 	enum outmode	 outmode;
@@ -251,9 +252,14 @@ main(int argc, char *argv[])
 			break;
 		case 'O':
 			search.outkey = optarg;
-			while (optarg != NULL)
-				manconf_output(&conf.output,
-				    strsep(&optarg, ","));
+			while (optarg != NULL) {
+				thisarg = optarg;
+				if (manconf_output(&conf.output,
+				    strsep(&optarg, ","), 0) == 0)
+					continue;
+				warnx("-O %s: Bad argument", thisarg);
+				return (int)MANDOCLEVEL_BADARG;
+			}
 			break;
 		case 'S':
 			search.arch = optarg;