extern "C" { fn from_lib1(); } #[no_mangle] extern "C" fn from_lib2() { println!("hello world from rust"); } #[no_mangle] pub extern "C" fn c_func() { unsafe { from_lib1(); } } /// ``` /// #[cfg(not(nodep))] use lib12::rust_func; /// #[cfg(nodep)] use lib12_nodep::rust_func; /// rust_func(); /// ``` pub fn rust_func() { unsafe { from_lib1(); } }