messense

Some proptests failed in https://github.com/PyO3/pyo3/actions/runs/3104312627/jobs/5028714517

> where should I commit the fix? A separate branch and PR? Yes.

`No module named 'setuptools.command.build'` means `setuptools` version is too old, try upgrade it first: `pip install -U setuptools`.

> RUSTFLAGS="--target=aarch64-unknown-linux-gnu I think this is problematic, `--target` should not be specified in `RUSTFLAGS` since `RUSTFLAGS` will applies to both build scripts (when no `--target` argument is passed to `cargo...

`wasm32-wasi` std library also needs to be installed via `rustup`.

Add `rustup target add wasm32-wasi` to https://github.com/PyO3/maturin/blob/fb130c951d780578a3b0a58666aa33f704de68fb/.cirrus.yml#L51 and https://github.com/PyO3/maturin/blob/fb130c951d780578a3b0a58666aa33f704de68fb/.cirrus.yml#L76 should resolve the test failures on Cirrus CI.

> The error looks like it's missing the link-arg=-undefined/link-arg=dynamic_lookup, even though they are present and work for the top level crate. I think it's because we are using `cargo rustc`...

See also https://github.com/PyO3/setuptools-rust/issues/235

> cibuildwheel uses the `pyproject.toml` setup, so it uses maturin's pep 517 support. Yes, if anything goes wrong, feel free to report to maturin. BTW, I think cibuildwheel is not...

> By "good fit" do you mean unable to build for non-x86 or just longer build times M1 is different, it's actually cross compiling which is fast enough. The QEMU...