1FROM ubuntu:18.04 2RUN apt-get update && \ 3 apt-get install -y --no-install-recommends \ 4 gcc libc6-dev ca-certificates \ 5 gcc-arm-linux-gnueabihf libc6-dev-armhf-cross qemu-user-static 6ENV CARGO_TARGET_ARMV7_UNKNOWN_LINUX_GNUEABIHF_LINKER=arm-linux-gnueabihf-gcc \ 7 CARGO_TARGET_ARMV7_UNKNOWN_LINUX_GNUEABIHF_RUNNER=qemu-arm-static \ 8 QEMU_LD_PREFIX=/usr/arm-linux-gnueabihf \ 9 RUST_TEST_THREADS=1 10