===================================================================
RCS file: /cvsrepo/anoncvs/cvs/src/usr.bin/rcs/diff3.c,v
retrieving revision 1.41
retrieving revision 1.42
diff -u -r1.41 -r1.42
--- src/usr.bin/rcs/diff3.c	2016/10/18 21:06:52	1.41
+++ src/usr.bin/rcs/diff3.c	2019/08/10 16:13:46	1.42
@@ -1,4 +1,4 @@
-/*	$OpenBSD: diff3.c,v 1.41 2016/10/18 21:06:52 millert Exp $	*/
+/*	$OpenBSD: diff3.c,v 1.42 2019/08/10 16:13:46 stsp Exp $	*/
 
 /*
  * Copyright (C) Caldera International Inc.  2001-2002.
@@ -496,7 +496,7 @@
 				if (lp == NULL)
 					errx(1, "ed_patch_lines");
 
-				if (!memcmp(lp->l_line, ".", 1))
+				if (lp->l_len == 2 && lp->l_line[0] == '.')
 					break;
 
 				TAILQ_REMOVE(&(plines->l_lines), lp, l_list);