Support compile time linking.

[wmedrano]

It was removed in 0.10.0 in favor of manually finding the dynamic library and loading symbols.

[robbert-vdh]

As I mentioned in #179, the jack crate now always links to libjack, even if the dynamic loading feature is enabled. If the dynamic_loading feature is enabled, then the dynamic linking modules probably shouldn't be generated and included.

[wmedrano]

As I mentioned in #179, the jack crate now always links to libjack, even if the dynamic loading feature is enabled. If the dynamic_loading feature is enabled, then the dynamic linking modules probably shouldn't be generated and included.

How does #180 look?

[robbert-vdh]

I guess that probably works. Does functions::dynamic_loading always need to be re-exported (or be available even) even when using compile-time dynamic linking?

[andrewbaxter]

In Nix, I think the Cargo package wrapper uses patchelf to change dynamically linked paths to the correct place on the built system. I think this essentially operates on the information displayed by ldd.

Because libjack2.so.0 is runtime (? manually? programmatically?) linked it's not discovered and updated, and it fails to start at runtime.

I realize Nix users might be minor, but I think there's many other tools that rely on ldd information and libjack may be used in a wide variety of software, some of which may be impacted.

[wmedrano]

1. @andrewbaxter do you know if things can work with default-features = false? This should disable the dynamic loading.
2. libjack2.so.0 is hardcoded, I think. We can allow injecting it but I'm not even sure that is very Nix like.
3. For nix, I'm sorry but it isn't something I run or want to spend time looking into. 🙃 However, if you have some examples on how to make a GitHub action setup for testing nix stuff we can try to include it to make supporting and not breaking nix a bit better.

[andrewbaxter]

Thanks for the gracious offer!

To be clear, I wasn't asking for nix support. I was just adding a use case where having compile time linking vs dlopen. If compile time linking is supported then nix should be fine, as long as that's used.

1. do you know if things can work with default-features = false? This should disable the dynamic loading.

Sorry, I'm not sure I'm entirely following. In your first post you said

It was removed in 0.10.0

Was it re-added afterward? In that case maybe this issue could be closed.