Error on prepare_freethreaded_python in crate pyo3 on OSX Big Sur

[sansyrox]

🐛 Bug Reports

When reporting a bug, please provide the following information. If this is not a bug report you can just discard this template.

I am getting the error : prepare_freethreaded_python in crate pyo3 on OSX Big Sur when I am using the prepare_freethreaded_python function.

I also opened an issue(#1686) earlier, it was fixed then but it is not working with the latest release.

🌍 Environment

• Your operating system and version: OSX Big Sur
• Your python version: 3.9
• How did you install python (e.g. apt or pyenv)? Did you use a virtualenv?:
• Your Rust version (rustc --version): 1.50.0 (cb75ad5db 2021-02-10
• Your PyO3 version: 0.13.2
• Have you tried using latest PyO3 main (replace version = "0.x.y" with git = "https://github.com/PyO3/pyo3")?:

💥 Reproducing

Please provide a minimal working example. This means both the Rust code and the Python.

use pyo3::prelude::*;
use pyo3::wrap_pyfunction;

use std::future::Future;

#[pymodule]
pub fn robyn(py: Python<'_>, m: &PyModule) -> PyResult<()> {
    pyo3_asyncio::try_init(py).unwrap();
    pyo3::prepare_freethreaded_python();

    Ok(())
}

Error message:

error[E0425]: cannot find function `prepare_freethreaded_python` in crate `pyo3`
  --> src/lib.rs:29:11
   |
29 |     pyo3::prepare_freethreaded_python();
   |           ^^^^^^^^^^^^^^^^^^^^^^^^^^^ not found in `pyo3`

My toml file

[lib]
name = "robyn"
crate-type = ["cdylib", "rlib"]


[dependencies]
tokio = { version = "1.7.0", features = ["full"] }
dashmap = "4.0.2"
hyper = { version="0.14.9", features = ["full"]}
anyhow = "1.0.38"
notify = "4.0.0"
pyo3 = { version = "0.14.1", features = ["extension-module"] }
pyo3-asyncio = { version = "0.13", features = ["attributes", "tokio-runtime"] }
async-std = "1.9"

[patch.crates-io]
pyo3 = {git = "https://github.com/PyO3/pyo3/",branch = "main", features = ["extension-module"]}

Please also write what exact flags are required to reproduce your results.

[davidhewitt]

Can you reproduce this without pyo3-asyncio? This function will now always be present unless you are using PyPy, so I suspect build configuration error.

[sansyrox]

@davidhewitt , it's working now. I had to run cargo update and it started to work. But now I have a different issue:

🍹 Building a mixed python/rust project
💥 maturin failed
  Caused by: Expected exactly one pyo3 dependency, found 2

[sansyrox]

Can you reproduce this without pyo3-asyncio? This function will now always be present unless you are using PyPy, so I suspect build configuration error.

It works without pyo3-asyncio but gives the above error with it.

[davidhewitt]

Yeah, you won't be able to build with pyo3-asyncio until it releases an update to PyO3 0.14.

I'm going to close this issue as the problem is in dependencies not being ready.

[sansyrox]

@davidhewitt , is there a possible way to build it with older version maybe the previous version and use pyo3-asyncio with it?

[davidhewitt]

In PyO3 0.13 you'll experience this issue if your interpreter is not built with Py_ENABLE_SHARED. See #763 for a note how to install python on Mac with a shared library.