===================================================================
RCS file: /cvs/mandoc/mdoc_html.c,v
retrieving revision 1.277
retrieving revision 1.278
diff -u -p -r1.277 -r1.278
--- mandoc/mdoc_html.c	2017/03/15 11:29:53	1.277
+++ mandoc/mdoc_html.c	2017/03/17 12:10:16	1.278
@@ -1,4 +1,4 @@
-/*	$Id: mdoc_html.c,v 1.277 2017/03/15 11:29:53 schwarze Exp $ */
+/*	$Id: mdoc_html.c,v 1.278 2017/03/17 12:10:16 schwarze Exp $ */
 /*
  * Copyright (c) 2008-2011, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2014, 2015, 2016, 2017 Ingo Schwarze <schwarze@openbsd.org>
@@ -501,7 +501,8 @@ mdoc_sh_pre(MDOC_ARGS)
 	case ROFFT_HEAD:
 		id = html_make_id(n);
 		print_otag(h, TAG_H1, "cTi", "Sh", id);
-		print_otag(h, TAG_A, "chR", "selflink", id);
+		if (id != NULL)
+			print_otag(h, TAG_A, "chR", "selflink", id);
 		free(id);
 		break;
 	case ROFFT_BODY:
@@ -524,7 +525,8 @@ mdoc_ss_pre(MDOC_ARGS)
 
 	id = html_make_id(n);
 	print_otag(h, TAG_H2, "cTi", "Ss", id);
-	print_otag(h, TAG_A, "chR", "selflink", id);
+	if (id != NULL)
+		print_otag(h, TAG_A, "chR", "selflink", id);
 	free(id);
 	return 1;
 }