Added a dockerfile to build compiling environment to build X86, ARM, and RISCV binaries.

[hnpl]

The X86 and ARM gcc compilers are Ubuntu packages. The script clones RISCV-gnu-toolchain repo, checkouts a commit hash and compiles the tools.
Compiling RISCV-gcc takes lots of memory, so -m should be set for building the image.
A few concerns:

• Do we need to point to a specific gcc versions for the Ubuntu packages?
• Do we need to checkout a specific commit hash for the RISCV repo?
• I usually use the -v option to mount from host to docker. This causes a problem as the binaries would be owned by root on host. Is there a better way of doing this? I think we can add a new non-root user to the guest, and use chown to change the owner of the binaries.

[powerjg]

The way to fix the files being owned by root is to use the -u option with docker. For instance, below is the docker command I always use.

docker run --rm -v $PWD:$PWD -w $PWD -u $UID:$GID -it <image>

[powerjg]

This is a great start!

Can you create three separate dockerfiles for each one of them?

[powerjg]

It would be good to get @hildebrandmw 's feedback once this is updated with separate files.

[powerjg]

This is much better! Yeah, it sounds like there's tradeoffs between separate commands per RUN and everything in one RUN command. For our use case, I feel like the improved speed for debugging is more important than improved speed for building. Neither of which matters much ;)

[powerjg]

Sorry for the late comment... can you checkout a tag instead of a hash? Are there tags for specific versions of gcc?

[hnpl]

They have tags, each has a specific version of gcc.

[powerjg]

Let's pick one and use that tag. Let's use the same version as in the ubuntu repos, if possible.

…

On Mon, Jul 15, 2019 at 10:00 AM Hoa Nguyen ***@***.***> wrote: ***@***.**** commented on this pull request. ------------------------------ In Dockerfile_RISCV <#5 (comment)>: > @@ -0,0 +1,22 @@ +FROM ubuntu:18.04 +RUN apt-get update +RUN apt-get install -y build-essential git curl gawk texinfo expat \ + libexpat1-dev bison flex libz-dev python autoconf +# Prepare to download and compile RISCV toolchain +ENV HOME_DIR=/home/root +ENV RISCV_SRC_DIR=$HOME_DIR/riscv-gnu-toolchain +ENV RISCV_DIR=$HOME_DIR/riscv-tools +RUN mkdir -p $HOME_DIR +WORKDIR $HOME_DIR +RUN git clone --recursive https://github.com/riscv/riscv-gnu-toolchain -j $(nproc) +WORKDIR $RISCV_SRC_DIR +# Checkout a specific hash to keep the output binaries consistent +RUN git checkout 23a038856764808d75b6afe96f649980609ae4c6 They have tags, each has a specific version of gcc. — You are receiving this because your review was requested. Reply to this email directly, view it on GitHub <#5?email_source=notifications&email_token=AAA2YHB7CM4C52VK4ODQYZ3P7SUJTA5CNFSM4IDLG662YY3PNVWWK3TUL52HS4DFWFIHK3DMKJSXC5LFON2FEZLWNFSXPKTDN5WW2ZLOORPWSZGOB6ORC6Q#discussion_r303537998>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAA2YHFVROXT3CGMQFU3FJTP7SUJTANCNFSM4IDLG66Q> .

-- Jason Lowe-Power (he/him/his) Assistant Professor, Computer Science Department University of California, Davis 3049 Kemper Hall https://arch.cs.ucdavis.edu/

[hnpl]

The riscv-gnu-toolchain repo newest release was in December 2017, and it uses gcc 7.2.0. There are 2 newer tags since then. Do you think it is better to use the newer tags or the latest release?

[powerjg]

IIRC, RISC-V support is now mainlined in GCC. You might be able to use the main GCC repo instead of using the fork. Although, with 5 minutes of googling I couldn't figure out how to do it. So, it may not be possible.

@nganjehloo, do you have any ideas on the best version of the RISC-V toolchain to use?