In usr.bin/bgplg, ping6/Makefile is left-over from ping(6) unification.
However, there is no ping6 folder anymore:
$ cd /usr/src/usr.bin/bgplg/ping6/ && make
*** Parse error in /usr/src/usr.bin/bgplg/ping6: Could not find
/usr/src/usr.bin/bgplg/ping6/../../../sbin/ping6/Makefile (Makefile:9)
Attached diff removes ping6/Makefile, ping/Makefile already links ping6
-> ping.
Clemens
Index: ping6/Makefile
===================================================================
RCS file: ping6/Makefile
diff -N ping6/Makefile
--- ping6/Makefile 23 Dec 2014 19:32:16 -0000 1.2
+++ /dev/null 1 Jan 1970 00:00:00 -0000
@@ -1,14 +0,0 @@
-# $OpenBSD: Makefile,v 1.2 2014/12/23 19:32:16 pascal Exp $
-
-PROGDIR= ${.CURDIR}/../../../sbin/ping6
-
-LDSTATIC= ${STATIC}
-CFLAGS+= -I${PROGDIR}
-NOMAN= yes
-
-.include "${PROGDIR}/Makefile"
-
-BINDIR= /var/www/bin
-BINMODE= 000
-
-.PATH: ${PROGDIR}
