RISC-V wheels?

[weiji14]

Hi there,

Would it be possible to get riscv64 wheels uploaded onto PyPI? I hit into this error on my CI with the recent mypy=2.0.0 update depending on ast-serialize:

Collecting ast-serialize<1.0.0,>=0.3.0 (from mypy)
  Downloading ast_serialize-0.3.0.tar.gz (60 kB)
  Installing build dependencies: started
  Installing build dependencies: finished with status 'done'
  Getting requirements to build wheel: started
  Getting requirements to build wheel: finished with status 'done'
  Preparing metadata (pyproject.toml): started
  Preparing metadata (pyproject.toml): finished with status 'error'
  error: subprocess-exited-with-error
  
  × Preparing metadata (pyproject.toml) did not run successfully.
  │ exit code: 1
  ╰─> [10 lines of output]
      error: could not execute process `sccache /home/runner/.rustup/toolchains/1.94.1-riscv64gc-unknown-linux-gnu/bin/rustc -vV` (never executed)

Looks like riscv64 could be added to the matrix builds here:

ast_serialize/.github/workflows/build_wheels.yml

Lines 20 to 34 in 9960789

	strategy:
	matrix:
	platform:
	- runner: ubuntu-22.04
	target: x86_64
	- runner: ubuntu-22.04
	target: x86
	- runner: ubuntu-22.04
	target: aarch64
	- runner: ubuntu-22.04
	target: armv7
	- runner: ubuntu-22.04
	target: s390x
	- runner: ubuntu-22.04
	target: ppc64le

maturin-action should support either cross-compiling or native builds (search https://github.com/PyO3/maturin-action#manylinux-docker-container for riscv64). Cross-compiling would be easiest, as native builds are more involved (need to use https://github.com/riseproject-dev/riscv-runner-images or similar) and probably only needed if running tests (which doesn't seem to be the case).

Let me know which option to go with and I can help submit a PR if that's ok.

[JukkaL]

Can you find some examples of projects that provide RISC-V wheels built using maturin? It's probably not a problem, but I'd be hesitant to be one of earliest adopters in case this is something very new.

[weiji14]

Sure, here's some I found via this search, they've been around for quite a few months now:

• Add riscv64 build, make Linux wheel build matrix more explicit huggingface/tokenizers#1951
• Feature/build riscv64 bin astral-sh/ruff#19819
• Build wheels for more platforms j178/prek#489

And here's one PR that's in progress - pola-rs/polars#27149 which is a little blocked because it's trying to use native builds. I've managed to get native builds running myself at weiji14/cog3pio#88, which required a few hacks (hence why I'd recommend cross compiling instead, similar to what this repo is doing for armv7/ppc64le/s390x).

[weiji14]

Opened #66 in case you want to test out the build.