Polkadot Raspberry PI (64 bit) cross-compile build

cross-build.sh

#!/usr/bin/env bash

# Run this file from the root of substrate / polkadot directory.

DOCKER_IMAGE="polkadot/rpi"

docker build -t $DOCKER_IMAGE .
docker run --rm -it \
	--env BINDGEN_EXTRA_CLANG_ARGS="--sysroot=/usr/aarch64-unknown-linux-gnu -D__ARM_PCS_VFP -mfpu=vfp -mfloat-abi=hard" \
	--env CARGO_HOME=/home/rust/src/cargo_home \
	-v "$(pwd)":/home/rust/src polkadot/rpi \
	cargo +nightly build -Z features=itarget --target=aarch64-unknown-linux-gnu --release

Dockerfile

# Put this file in the root of substrate / polkadot directory.

FROM rust:latest

RUN dpkg --add-architecture arm64 && \
    apt-get update && apt-get upgrade -y && \
    apt-get install -y aptitude && \
    aptitude install -y \
        gcc-aarch64-linux-gnu \
        g++-aarch64-linux-gnu \
        pkg-config \
        cmake \
        libssl-dev \
        git \
        clang \
        libclang-dev \
	libz-dev:arm64 \
	libssl-dev:arm64

RUN rustup install nightly
RUN rustup target add aarch64-unknown-linux-gnu --toolchain nightly
RUN rustup target add wasm32-unknown-unknown --toolchain nightly
RUN cargo +nightly install --git https://github.com/alexcrichton/wasm-gc --force

ENV CARGO_TARGET_AARCH64_UNKNOWN_LINUX_GNU_LINKER=aarch64-linux-gnu-gcc
ENV CARGO_TARGET_AARCH64_UNKNOWN_LINUX_GNU_RUNNER="/linux-runner aarch64"
ENV CC_aarch64_unknown_linux_gnu=aarch64-linux-gnu-gcc
ENV CXX_aarch64_unknown_linux_gnu=aarch64-linux-gnu-g++
ENV PKG_CONFIG_ALLOW_CROSS 1
ENV PKG_CONFIG_PATH /usr/lib/aarch64-unknown-linux-gnu/pkgconfig/

RUN useradd rust --user-group --create-home --shell /bin/bash --groups sudo
WORKDIR /home/rust/src