diff --git a/usr.sbin/bsdinstall/Makefile b/usr.sbin/bsdinstall/Makefile
index 75db149b814b..e5bb3197fa05 100644
--- a/usr.sbin/bsdinstall/Makefile
+++ b/usr.sbin/bsdinstall/Makefile
@@ -1,32 +1,35 @@
 SUBDIR=	distextract distfetch include partedit runconsoles scripts
 SUBDIR_PARALLEL=
 SUBDIR_DEPEND_distextract = include
 SUBDIR_DEPEND_distfetch = include
 SUBDIR_DEPEND_partedit = include
 SCRIPTS= bsdinstall
 MAN= bsdinstall.8
 PACKAGE=	bsdinstall
 
 SCRIPTS+=	startbsdinstall
 SCRIPTSDIR_startbsdinstall=	${LIBEXECDIR}/bsdinstall
 
 UPDATE_DEPENDFILE= no
 
 FILESDIR=	${SHAREDIR}/bsdinstall
 FILES=		FreeBSD-base.conf
 
 _BRANCH!=	${MAKE} -C ${SRCTOP}/release -V BRANCH
 BRANCH?=	${_BRANCH}
 _REVISION!=	${MAKE} -C ${SRCTOP}/release -V REVISION
 REVISION?=	${_REVISION}
 
 .if ${BRANCH} == CURRENT || ${BRANCH} == STABLE
 SUBURL=		base_latest
-.else
+.elif ${BRANCH} == RELEASE
 SUBURL=		base_release_${REVISION:C/[0-9]+\.//}
+.else
+.warning Invalid branch "${BRANCH}"
+SUBURL=		base_latest
 .endif
 
 FreeBSD-base.conf: FreeBSD-base.conf.in
 	sed "s|%%SUBURL%%|${SUBURL}|" < ${.ALLSRC} > ${.TARGET}
 
 .include <bsd.prog.mk>