I have a toy RISC-V simulator I wrench on for fun, for which I'd like to compile code.
Setting up a cross compiler is always a chore, and doing so for a variety of host platforms is even worse. I learned this when moving laptops.
So, I went with a Docker approach.
Pull the image:
docker pull notthatjonsmith/riscv-cross-toolkit:latest
Or set up the docker image locally:
git submodule update --init
docker build -t crosstools
Run this repo's makefile flow from within the container:
docker run --rm --mount type=bind,source="$(pwd)",target=/host_mount_dir crosstools /host_mount_dir/build-me.sh
The container bind-mounts the current working dir, and then effective does "make" here, but with the superpower of having a stable cross-compiler setup.
git submodule update --init: there's a heap of submodules under external. It's a mixture of components required to build the cross toolchain in the image (container? idk) and components to cross-build for risc-v systems.
docker build -t crosstools sets up an Ubuntu (one day something slimmer, I hope) system with all the GCC build prerequisites.
Then, it copies the whole external dir into /repos in the docker image.
Then, it copies the script build-cross-rv-tools.sh in, and runs it several times to set up the cross tools you need.
The Makefile here is meant to be run from within the container. I wrap it with a short bash script (I honestly forgot why) and run it like this:
docker run --rm --mount type=bind,source="$(pwd)",target=/host_mount_dir crosstools /host_mount_dir/build-me.sh
So now we have a make project that has access to a risc-v cross toolchain. Neat!
There are probably a million and one ways to make this cleaner and better.