Let pyconfig.h not define Py_ENABLE_SHARED

[dalcde]

If there is no line that defines Py_ENABLE_SHARED in pyconfig.h, then it is false

This fixes an issue described in #1221

[davidhewitt]

Hi @dalcde thanks very much for the PR.

I'm slightly reluctant to merge this, because the header parsing is slightly broken for a few various reasons and I'm thinking about removing it anyway in PyO3 0.14. See #1337

Can you tell me a bit more about your use case? Perhaps we can come up with a better way to configure PyO3 in your situation.

[dalcde]

On Mon, Jan 04, 2021 at 12:24:04PM -0800, David Hewitt wrote: Can you tell me a bit more about your use case? Perhaps we can come up with a better way to configure PyO3 in your situation.

I'm looking into building pyo3 packages to wasm32-unknown-unknown for use with https://github.com/iodide-project/pyodide . If I set CARGO_CFG_TARGET_FAMILY=unix I get

Your Rust target architecture (32-bit) does not match your python interpreter (64-bit)

and if I set it to windows it doesn't complain about this but it uses the header file instead. I'm most likely not going about this the right way, but on the other hand what this PR does is more correct behaviour.

[kngwyu]

Thanks!

[kngwyu]

I'm slightly reluctant to merge this, because the header parsing is slightly broken for a few various reasons and I'm thinking about removing it anyway in PyO3 0.14.

I don't think it's very straightforward to remove the header parsing and it'll take time. So I don't think merging this now is harmful.

[davidhewitt]

Ok 👍