Static linking is too restrictive

[yshui]

pkg-config-rs/src/lib.rs

Lines 570 to 581 in ef356f3

	fn is_static_available(name: &str, dirs: &[PathBuf]) -> bool {
	let libname = format!("lib{}.a", name);
	let system_roots = if cfg!(target_os = "macos") {
	vec![Path::new("/Library"), Path::new("/System")]
	} else {
	vec![Path::new("/usr")]
	};
	dirs.iter().any(|dir| {
	!system_roots.iter().any(|sys| dir.starts_with(sys)) && dir.join(&libname).exists()
	})
	}

Basically any library which falls into /usr/lib/ won't be statically linked (which is basically all libraries found by pkg-config). Why is this logic there?

[sdroege]

That seems to come from 9a57960 by @alexcrichton . I don't understand the rationale given in the commit message though. Maybe he can explain :)

[alexcrichton]

Hm given how that was around 7 years ago, I don't really remember much about the context... 99% of the time commits like that were "this fixes a bug somewhere" and I didn't do a great job of documenting what bug was fixed where. I don't currently remember what bug was fixed either, so sorry but I don't think I can be of much help :(

[yshui]

Maybe we can remove it now?

[sdroege]

Possibly, but most likely it will break someone's setup :)

I'd like to do a pkg-config 0.5 release in the future that drops all these weird hacks that come without explanation and instead rely solely on the default pkg-config behavior (and if needed people can override that with the pkg-config environment variables, we don't have to set them ourselves, or with a wrapper script). Currently this crate is rather opinionated about the build environment, which causes a couple of problems.

[cjordan]

I've just come up against this issue. Is there something I could do to help accelerate the next big release of pkg-config?

[toxeus]

@sdroege wrote:

Possibly, but most likely it will break someone's setup :)

Maybe we can introduce another env var to disable the current behavior that refuses to statically link system libs? A quick and quite dirty workaround already exists by setting, e.g. SYSROOT=/asdf but it would be nicer to have something explicit rather than relying on such side-effects.

[otavio]

@sdroege, any news in providing a way to get it linking to static libraries more easily?

[jirutka]

@alexcrichton, can you please remove this “feature” or at least allow us to disable it via an environment variable? It is clearly wrong and based on some weird assumption that doesn’t hold universally. The workaround with SYSROOT=/dummy cannot be used when cross-compiling.

[toxeus]

@sdroege established a plan on how to move forward but nothing happened since 2 years.