The NetBSD-current/i386 build is working again. The following commits were made between the last failed build and the successful build:
2018.04.10.06.32.23 maxv src/doc/TODO.npf,v 1.2 2018.04.10.07.05.39 ozaki-r src/sys/net/if_bridge.c,v 1.149 2018.04.10.07.09.00 ozaki-r src/tests/net/if_bridge/t_rtable.sh,v 1.2 Log files can be found at: http://releng.NetBSD.org/b5reports/i386/commits-2018.04.html#2018.04.10.07.09.00