[vvanders]

That only applies when dynamic dispatch is involved and the linker can't trace the calls. For direct calls and generics(which idiomatic Rust code tends to prefer over dyn traits) LTO will prune extensively.

[rafram]

    let uri = get_uri_from_stdin();
    networking_library::make_request(uri);

How is the compiler supposed to prune that?

[f_devd]

  let uri: Uri<HTTP> = get_uri_from_stdin().parse()?; 

If the library is made in a modular way this is how it would typically be done. The `HTTP` may be inferred by calls further along in the function.