All of the gcc-toolchain builders are failing in build_packages step.
There are four packages that consistently fail to build: chromeos-base/verity, net-misc/iperf, sys-devel/binutils, and dev-libs/boost
(dev-libs/boost builds fine on x86, but fails on amd64, arm, and arm64).

Some recent examples:

amd64: https://uberchromegw.corp.google.com/i/chromeos/builders/amd64-gcc-toolchain/builds/129
arm: https://uberchromegw.corp.google.com/i/chromeos/builders/arm-gcc-toolchain/builds/129
arm64: https://uberchromegw.corp.google.com/i/chromeos/builders/arm64-gcc-toolchain/builds/129
x86: https://uberchromegw.corp.google.com/i/chromeos/builders/x86-gcc-toolchain/builds/128