The NetBSD-current/i386 build is working again. The following commits were made between the last failed build and the successful build:
2018.11.28.00.44.08 kre src/usr.sbin/sysinst/label.c,v 1.6 Log files can be found at: http://releng.NetBSD.org/b5reports/i386/commits-2018.11.html#2018.11.28.00.44.08