The NetBSD-current/i386 build is working again. The following commits were made between the last failed build and the successful build:
2016.09.13.00.45.15 christos src/sys/netinet/in_var.h,v 1.81 2016.09.13.00.45.15 christos src/sys/netinet6/in6_var.h,v 1.86 Log files can be found at: http://releng.NetBSD.org/b5reports/i386/commits-2016.09.html#2016.09.13.00.45.15