The NetBSD-current/i386 build is working again. The following commits were made between the last failed build and the successful build:
2016.12.13.20.42.15 christos src/sys/arch/acorn32/conf/EB7500ATX,v 1.61 2016.12.13.20.42.15 christos src/sys/arch/acorn32/conf/GENERIC,v 1.120 2016.12.13.20.42.15 christos src/sys/arch/acorn32/conf/INSTALL,v 1.76 2016.12.13.20.42.15 christos src/sys/arch/acorn32/conf/LOWMEM_WSCONS,v 1.70 2016.12.13.20.42.15 christos src/sys/arch/acorn32/conf/NC,v 1.69 2016.12.13.20.42.15 christos src/sys/arch/algor/conf/P5064,v 1.84 2016.12.13.20.42.15 christos src/sys/arch/algor/conf/P6032,v 1.75 2016.12.13.20.42.16 christos src/sys/arch/alpha/conf/GENERIC,v 1.375 2016.12.13.20.42.16 christos src/sys/arch/amd64/conf/ALL,v 1.44 2016.12.13.20.42.16 christos src/sys/arch/amd64/conf/GENERIC,v 1.447 2016.12.13.20.42.16 christos src/sys/arch/amd64/conf/XEN3_DOM0,v 1.123 2016.12.13.20.42.16 christos src/sys/arch/amiga/conf/AMIGA,v 1.111 2016.12.13.20.42.16 christos src/sys/arch/amiga/conf/DRACO,v 1.180 2016.12.13.20.42.16 christos src/sys/arch/amiga/conf/GENERIC,v 1.314 2016.12.13.20.42.16 christos src/sys/arch/amiga/conf/GENERIC.in,v 1.132 2016.12.13.20.42.16 christos src/sys/arch/amiga/conf/MDINSTALL,v 1.35 2016.12.13.20.42.16 christos src/sys/arch/amigappc/conf/GENERIC,v 1.29 2016.12.13.20.42.16 christos src/sys/arch/amigappc/conf/NULL,v 1.49 2016.12.13.20.42.16 christos src/sys/arch/atari/conf/GENERIC.in,v 1.112 2016.12.13.20.42.16 christos src/sys/arch/atari/conf/HADES,v 1.110 2016.12.13.20.42.16 christos src/sys/arch/atari/conf/HADES.in,v 1.15 2016.12.13.20.42.16 christos src/sys/arch/atari/conf/MILAN-ISAIDE,v 1.87 2016.12.13.20.42.16 christos src/sys/arch/atari/conf/MILAN-PCIIDE,v 1.91 2016.12.13.20.42.16 christos src/sys/arch/bebox/conf/GENERIC,v 1.151 2016.12.13.20.42.16 christos src/sys/arch/bebox/conf/INSTALL,v 1.59 2016.12.13.20.42.16 christos src/sys/arch/cats/conf/GENERIC,v 1.161 2016.12.13.20.42.16 christos src/sys/arch/cats/conf/INSTALL,v 1.101 2016.12.13.20.42.17 christos src/sys/arch/cobalt/conf/GENERIC,v 1.151 2016.12.13.20.42.17 christos src/sys/arch/cobalt/conf/INSTALL,v 1.62 2016.12.13.20.42.17 christos src/sys/arch/dreamcast/conf/GENERIC,v 1.125 2016.12.13.20.42.17 christos src/sys/arch/epoc32/conf/GENERIC,v 1.11 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/ALLWINNER_A80,v 1.19 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/ARMADILLO9,v 1.52 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/BPI,v 1.20 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/CUBIEBOARD,v 1.49 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/GUMSTIX,v 1.89 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/HDL_G,v 1.48 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/HPT5325,v 1.30 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/HUMMINGBIRD_A31,v 1.27 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/IMX23_OLINUXINO,v 1.15 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/LUBBOCK,v 1.57 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/MINI2440,v 1.19 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/MMNET_GENERIC,v 1.26 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/MPCSA_GENERIC,v 1.48 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/MV2120,v 1.30 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/POGO,v 1.3 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/RPI,v 1.71 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/SHEEVAPLUG,v 1.52 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/SMDK2410,v 1.62 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/TEGRA,v 1.10 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/TS7200,v 1.66 2016.12.13.20.42.17 christos src/sys/arch/evbarm/conf/TWINTAIL,v 1.69 2016.12.13.20.42.17 christos src/sys/arch/evbmips/conf/ALCHEMY,v 1.60 2016.12.13.20.42.17 christos src/sys/arch/evbmips/conf/LOONGSON,v 1.29 2016.12.13.20.42.17 christos src/sys/arch/evbmips/conf/MALTA,v 1.85 2016.12.13.20.42.17 christos src/sys/arch/evbppc/conf/EV64260,v 1.67 2016.12.13.20.42.17 christos src/sys/arch/evbppc/conf/OPENBLOCKS266_OPT,v 1.22 2016.12.13.20.42.17 christos src/sys/arch/evbppc/conf/PMPPC,v 1.39 2016.12.13.20.42.18 christos src/sys/arch/hp300/conf/GENERIC,v 1.194 2016.12.13.20.42.18 christos src/sys/arch/hpcarm/conf/NETBOOKPRO,v 1.20 2016.12.13.20.42.18 christos src/sys/arch/hpcarm/conf/WZERO3,v 1.42 2016.12.13.20.42.18 christos src/sys/arch/hpcmips/conf/GENERIC,v 1.233 2016.12.13.20.42.18 christos src/sys/arch/hpcmips/conf/TX3922,v 1.105 2016.12.13.20.42.18 christos src/sys/arch/hpcmips/conf/VR41XX,v 1.68 2016.12.13.20.42.18 christos src/sys/arch/hppa/conf/GENERIC,v 1.11 2016.12.13.20.42.18 christos src/sys/arch/i386/conf/ALL,v 1.407 2016.12.13.20.42.18 christos src/sys/arch/i386/conf/GENERIC,v 1.1145 2016.12.13.20.42.18 christos src/sys/arch/i386/conf/GENERIC_TINY,v 1.146 2016.12.13.20.42.18 christos src/sys/arch/i386/conf/INSTALL_FLOPPY,v 1.34 2016.12.13.20.42.18 christos src/sys/arch/i386/conf/INSTALL_TINY,v 1.148 2016.12.13.20.42.18 christos src/sys/arch/i386/conf/XEN3_DOM0,v 1.102 2016.12.13.20.42.18 christos src/sys/arch/ibmnws/conf/GENERIC,v 1.49 2016.12.13.20.42.18 christos src/sys/arch/iyonix/conf/GENERIC,v 1.93 2016.12.13.20.42.19 christos src/sys/arch/landisk/conf/GENERIC,v 1.53 2016.12.13.20.42.19 christos src/sys/arch/macppc/conf/GENERIC,v 1.326 2016.12.13.20.42.19 christos src/sys/arch/macppc/conf/GENERIC_601,v 1.11 2016.12.13.20.42.19 christos src/sys/arch/mmeye/conf/MMEYE_WLF,v 1.20 2016.12.13.20.42.19 christos src/sys/arch/netwinder/conf/GENERIC,v 1.130 2016.12.13.20.42.19 christos src/sys/arch/ofppc/conf/GENERIC,v 1.161 2016.12.13.20.42.19 christos src/sys/arch/playstation2/conf/DEBUG,v 1.23 2016.12.13.20.42.19 christos src/sys/arch/pmax/conf/GENERIC,v 1.190 2016.12.13.20.42.20 christos src/sys/arch/pmax/conf/GENERIC64,v 1.24 2016.12.13.20.42.20 christos src/sys/arch/pmax/conf/INSTALL,v 1.74 2016.12.13.20.42.20 christos src/sys/arch/pmax/conf/INSTALL64,v 1.11 2016.12.13.20.42.20 christos src/sys/arch/prep/conf/GENERIC,v 1.180 2016.12.13.20.42.20 christos src/sys/arch/sandpoint/conf/ENCPP1,v 1.15 2016.12.13.20.42.20 christos src/sys/arch/sgimips/conf/GENERIC32_IP2x,v 1.108 2016.12.13.20.42.20 christos src/sys/arch/sgimips/conf/GENERIC32_IP3x,v 1.111 2016.12.13.20.42.20 christos src/sys/arch/shark/conf/GENERIC,v 1.126 2016.12.13.20.42.20 christos src/sys/arch/shark/conf/INSTALL,v 1.61 2016.12.13.20.42.20 christos src/sys/arch/sparc/conf/INSTALL,v 1.95 2016.12.13.20.42.20 christos src/sys/arch/sparc/conf/KRUPS,v 1.72 2016.12.13.20.42.20 christos src/sys/arch/sparc/conf/MRCOFFEE,v 1.51 2016.12.13.20.42.20 christos src/sys/arch/sparc/conf/TADPOLE3GX,v 1.70 2016.12.13.20.42.20 christos src/sys/arch/sparc64/conf/GENERIC,v 1.196 2016.12.13.20.42.20 christos src/sys/arch/sparc64/conf/NONPLUS64,v 1.50 2016.12.13.20.42.21 christos src/sys/arch/usermode/conf/GENERIC.common,v 1.24 2016.12.13.20.42.21 christos src/sys/arch/vax/conf/GENERIC,v 1.199 2016.12.13.20.42.21 christos src/sys/arch/x68k/conf/GENERIC,v 1.183 2016.12.13.20.42.21 christos src/sys/arch/x68k/conf/INSTALL,v 1.112 2016.12.13.20.42.21 christos src/sys/arch/zaurus/conf/GENERIC,v 1.70 2016.12.13.20.42.21 christos src/sys/arch/zaurus/conf/INSTALL,v 1.30 2016.12.13.20.50.13 christos src/sys/dev/spkr_synth.c,v 1.8 Log files can be found at: http://releng.NetBSD.org/b5reports/i386/commits-2016.12.html#2016.12.13.20.50.13