Move arm64 build to taskcluster.

[jdm]

This change is 

[jdm]

@bors-servo try=arm

[bors-servo]

⌛ Trying commit c245ca5 with merge 638c170...

[bors-servo]

💔 Test failed - status-taskcluster

[bors-servo]

☔ The latest upstream changes (presumably #23362) made this pull request unmergeable. Please resolve the merge conflicts.

[SimonSapin]

I attempted several times to reproduce this build in any environment other than buildbot workers, and gave up every time. Cross-compiling C or C++ code (SpiderMonkey in particular) with our build system is very brittle.

For quicker edit-run-error cycles, I suggest experimenting with a local Docker container. Repeatedly run docker build -t servo-tmp . in a directory with a Dockerfile, and keep successful intermediate commands in separate RUN instructions so that Docker caches their result as container layers.

(This can use up disk space quickly, so consider docker container prune and docker image prune after you’re done.)

[SimonSapin]

The unedited Dockerfile below is where I left off last time.

Other resources that might be helpful include:

• Env variables printed for a job such as https://build.servo.org/builders/arm64/builds/14563/steps/compile/logs/stdio
• A several-years-old blog post https://mmatyas.github.io/blog/servo-short-cross-compilation-guide
• The “rootfs” tarballs under https://servo-rust.s3.amazonaws.com/ARM/. I don’t know how they are created. They are installed on linux-cross-* workers here:
  • https://github.com/servo/saltfs/blob/c18e786a255679a3f8748adb0adb7fd4320e7a5c/servo-build-dependencies/map.jinja#L3-L18
  • https://github.com/servo/saltfs/blob/c18e786a255679a3f8748adb0adb7fd4320e7a5c/servo-build-dependencies/arm.sls

Good luck!

FROM ubuntu:trusty-20181217

ENV DEBIAN_FRONTEND=noninteractive
RUN apt-get update -q && apt-get install -qy --no-install-recommends \
    git \
    ca-certificates \
    python-virtualenv \
    curl
RUN curl https://sh.rustup.rs -sSf | sh -s -- --default-toolchain none -y
RUN git clone --depth 1 https://github.com/servo/servo /repo
WORKDIR /repo
ENV PATH="/root/.cargo/bin:$PATH"
RUN ./mach cargo fetch
ARG MACH_TARGET=aarch64-unknown-linux-gnu
RUN ./mach build --dev --target=$MACH_TARGET -p matches
ARG TARGET_NAME=aarch64-linux-gnu
ARG TARGET_DOWNLOAD_NAME=arm64-trusty-libs
ARG TARGET_SYMLINK_NAME=aarch64-unknown-linux-gnu
ARG TARGET_VERSION=v2
RUN apt-get install -y --no-install-recommends \
    make \
    g++ \
    g++-$TARGET_NAME
RUN mkdir $HOME/bin && \
    for bin in \
        elfedit gcov nm addr2line g++ objcopy ar objdump as gcc ranlib c++filt \
        gprof readelf cpp ld size ld.bfd strings strip \
    ; do \
        ln -s /usr/bin/$TARGET_NAME-$bin $HOME/bin/$TARGET_SYMLINK_NAME-$bin \
    ; done
#RUN mkdir /rootfs-$TARGET_DOWNLOAD_NAME-$TARGET_VERSION && ( \
#        export dir=$TARGET_DOWNLOAD_NAME/$TARGET_VERSION; \
#        export file=$TARGET_DOWNLOAD_NAME-$TARGET_VERSION.tgz; \
#        curl https://servo-rust.s3.amazonaws.com/ARM/$dir/$file \
#    ) \
#    | tar xz -C /rootfs-$TARGET_DOWNLOAD_NAME-$TARGET_VERSION
RUN ./mach build --dev --target=$MACH_TARGET -p libz-sys
RUN apt-get install -y --no-install-recommends \
        software-properties-common \
    && add-apt-repository ppa:ubuntu-toolchain-r/test && \
    apt-get update -q && \
    apt-get upgrade -y
RUN apt-get install -y --no-install-recommends \
    g++-5
RUN apt-get install -y --no-install-recommends \
    clang-4.0
RUN which gcc-5
#ENV CC_aarch64-unknown-linux-gnu=aarch64-linux-gnu-gcc
#RUN ./mach build --dev --target=$MACH_TARGET -p mozjs_sys

[SimonSapin]

The “rootfs” tarballs under https://servo-rust.s3.amazonaws.com/ARM/. I don’t know how they are created.

Last updated in servo/saltfs#268

[jdm]

I documented how to generate them in https://github.com/servo/servo/wiki/Preparing-ARM-libraries-for-CI

[jdm]

We've already got windows & magicleap arm64 builds on CI. I don't see a good reason to continue to maintain this build due to its complicated setup.

[SimonSapin]

Should we remove it from buildbot_steps.yml?

[jdm]

Yes.