add mingw CI

[davidhewitt]

No description provided.

[davidhewitt]

Hmm I think this isn't picking up the right Python

[davidhewitt]

Hmm seems like nox is misbehaving

[messense]

I think we should install Rust in msys2 shell or build it with --target x86_64-pc-windows-gnu.

Looks like it's using x86_64-pc-windows-msvc because it's the default toolchain.

[messense]

error: Rust build failed; unable to find any *html_py_ever.so in D:\a\setuptools-rust\setuptools-rust\examples\html-py-ever\target/release

Reproduced the issue.

[davidhewitt]

Nice work @messense!

Hmm I tried to use tmate action to get a debugging shell but I can't use it for some reason. Worked earlier, will try again later.

I think that the likely code is here:

setuptools-rust/setuptools_rust/build.py

Line 261 in 4c88c6a

if "win" in platform:

I think we probably need to check sys.platform on msys2 and then fixup that condition. Hence why I wanted a debug shell :)

[davidhewitt]

Sounds like from pypa/virtualenv#1338 (comment) that sys.platform might also be msys or maybe msys2.

To be honest I think the artifact suffix is really something controlled by rustc, so I'll refactor this condition to be based on the rust target.

[davidhewitt]

@messense so I've got the mingw builds working by reading artifacts from the cargo output messages. This is probably more robust than the previous implementation when cross-compiling too.

However hit a couple of breaking problems. Wonder if you've seen these in maturin & might know how to work around:

• cross uses different paths in the metadata so the copy fails (I think)
• cargo-zigbuild doesn't support cargo-zigbuild metadata. Unsure if it should?

(pytest job expected to fall, it's from the debug prints I've added.)

[messense]

cargo-zigbuild doesn't support cargo-zigbuild metadata. Unsure if it should?

I can add cargo-zigbuild metadata, it'd just delegate to cargo metadata since metadata command does not require special setup when cross compiling.

[messense]

Copying rust artifact from /target/aarch64-unknown-linux-gnu/release/libnamespace_package_rust.so to build/lib.linux-x86_64-cpython-38/namespace_package/rust.so

cross use docker containers, so it's the path in container not the host.

[davidhewitt]

cross use docker containers, so it's the path in container not the host.

Yeah I was aware of that, I was wondering if you knew how maturin avoided the same problem. Do you invoke cargo metadata and cross metadata so that you can see what each thinks the target directory is, and then map that onto each artifact path reported by cross?

[messense]

maturin does not support using cross yet 😅. PyO3/maturin#1002

[davidhewitt]

Fair enough! I seem to have reached an approach which works now by adjusting the target directory if using cross.

[messense]

👍