#[cfg(feature = "pkg-config")] extern crate pkg_config; fn main() { if !build_pkgconfig() { println!("cargo:rustc-flags=-l tag_c -l tag"); } } #[cfg(not(feature = "pkg-config"))] fn build_pkgconfig() -> bool { false } #[cfg(feature = "pkg-config")] fn build_pkgconfig() -> bool { if pkg_config::find_library("taglib_c").is_err() { panic!("Could not find taglib_c via pkgconfig"); } true }