diff --git a/external/bsd/elftoolchain/common/Makefile b/external/bsd/elftoolchain/common/Makefile
new file mode 100644
index 000000000000..f682a1131290
--- /dev/null
+++ b/external/bsd/elftoolchain/common/Makefile
@@ -0,0 +1,26 @@
+# $NetBSD: Makefile,v 1.1 2021/04/06 19:40:19 jkoshy Exp $
+
+.include <bsd.own.mk>
+
+TOP=	${.CURDIR}/../dist
+SRCDIR=	${TOP}/common
+
+.PATH:	${SRCDIR}
+
+SUBDIR=		sys
+
+INCS=		elfdefinitions.h
+INCSDIR=	/usr/include
+
+.PHONY:	all clean clobber depend obj
+
+all depend:
+
+clean clobber:
+	rm -f ${CLEANFILES}
+
+cleandepend:
+	rm -f ${.OBJDIR}/.depend
+
+.include <bsd.inc.mk>
+.include <bsd.subdir.mk>
diff --git a/external/bsd/elftoolchain/common/sys/Makefile b/external/bsd/elftoolchain/common/sys/Makefile
new file mode 100644
index 000000000000..34aff457095e
--- /dev/null
+++ b/external/bsd/elftoolchain/common/sys/Makefile
@@ -0,0 +1,28 @@
+# $NetBSD: Makefile,v 1.1 2021/04/06 19:40:19 jkoshy Exp $
+
+.include <bsd.own.mk>
+
+TOP=	${.CURDIR}/../../dist
+SRCDIR=	${TOP}/common/sys
+
+.PATH:	${SRCDIR}
+
+INCS=		elfdefinitions.h
+INCSDIR=	/usr/include/sys
+
+elfdefinitions.h:	elfdefinitions.m4 elfconstants.m4
+	${TOOL_M4} -I${SRCDIR} -D SRCDIR=${SRCDIR} ${M4FLAGS} \
+		elfdefinitions.m4 > ${.TARGET}
+
+.PHONY:	all clean clobber depend
+
+all depend:	elfdefinitions.h
+
+clean clobber:
+	rm -f ${INCS}
+
+cleandepend:
+	rm -f ${.OBJDIR}/.depend
+
+.include <bsd.inc.mk>
+.include <bsd.obj.mk>