prevent mandoc from segfaulting if /tmp is not writable;

patch from espie@

1 files changed, 5 insertions, 3 deletions

diff --git a/main.c b/main.c
index 8e8ca894..acd9cd92 100644
--- a/main.c
+++ b/main.c
@@ -1,4 +1,4 @@
-/*	$Id: main.c,v 1.327 2019/05/03 18:39:34 schwarze Exp $ */
+/*	$Id: main.c,v 1.328 2019/07/06 20:05:27 schwarze Exp $ */
 /*
  * Copyright (c) 2008-2012 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010-2012, 2014-2019 Ingo Schwarze <schwarze@openbsd.org>
@@ -504,7 +504,8 @@ main(int argc, char *argv[])
 	if (argc < 1) {
 		if (use_pager) {
 			tag_files = tag_init();
-			tag_files->tagname = conf.output.tag;
+			if (tag_files != NULL)
+				tag_files->tagname = conf.output.tag;
 		}
 		thisarg = "<stdin>";
 		mandoc_msg_setinfilename(thisarg);
@@ -542,7 +543,8 @@ main(int argc, char *argv[])
 			if (use_pager) {
 				use_pager = 0;
 				tag_files = tag_init();
-				tag_files->tagname = conf.output.tag;
+				if (tag_files != NULL)
+					tag_files->tagname = conf.output.tag;
 			}
 
 			mandoc_msg_setinfilename(thisarg);