pip install maturin fails under MSYS2

[elifarley]

Bug Description

pip install maturin
Collecting maturin
  Using cached maturin-1.7.8.tar.gz (195 kB)
[...]
Rust build failed; unable to locate executable 'maturin'

Your maturin version (maturin --version)

?

Your Python version (python -V)

3.12.7

Your pip version (pip -V)

24.3.1

What bindings you're using

None

Does cargo build work?

• Yes, it works

If on windows, have you checked that you aren't accidentally using unix path (those with the forward slash /)?

• Yes

Steps to Reproduce

• Install MSYS2 under Windows 11, x64
• Install rustup and rust
• Use pacman -S python to install Python 3.12.7
• Create a venv dir and activate it
• Run pip install maturin

maturin.log

[elifarley]

Just found out I have maturin under /c/Users/<user>/.cargo/bin/maturin.exe
I renamed it to remove .exe and now I can call it like this:

maturin -V
maturin 1.7.8

However, pip install maturin fails just as before.

[messense]

Unfortunately the log does not show anything abnormal, the related code is in https://github.com/PyO3/setuptools-rust/blob/2c6a567ddda35bded2ca91e12965328db7aa4668/setuptools_rust/build.py#L732-L779

You'd need to debug it by inspecting the temp cargo target directory when doing pip install --no-clean maturin.

cc @davidhewitt this could be a general setuptools-rust issue with MSYS2.

[elifarley]

There's a workaround:

I was using a venv created by a pacman-based Python (pacman -S python).

Now I just tested another venv, created by a Windows-native Python (from https://www.python.org/ftp/python/3.12.8/python-3.12.8-amd64.exe).

The latter works.