How to put linker flags in the back of the cc command

[vervaekejonathan]

Hello, Using the cc build command in build.rs like this:

    cc::Build::new()
        .compiler("g++-7")
        .cpp(true)
        .file("src/test.cpp")
        .include("...")
        .flag("-Llibrary_path")
        .flag("-llibrary")
        .compile("...");

this translates to roughly:

g++-7  -fPIC    -I ...   -Llibrary_path  -llibrary   src/test.cpp 

Which errors with an undefined reference error, the same one that I have when compiling it via cargo.

It does compile when I but the -llibrary flag in the back:

g++-7  -fPIC    -I ...   -Llibrary_path    src/test.cpp -llibrary 

A solution I found here: https://stackoverflow.com/questions/50642574/how-can-i-specify-linker-flags-arguments-in-a-build-script

My question: can this be done via the cc::build command? How can I put it in the back?

[vervaekejonathan]

Fixed it by adding the g++ -z rescan-now flag

 println!("cargo:rustc-link-arg=-z rescan-now");

[dot-asm]

You have to keep in mind that cc.compile() method simply compiles a static library. Passing -l options has no effect in the context. This compiled library is linked without you doing anything special. If you want link with a pre-existing library, you should rather have your build script emit "cargo:rustc-link-lib" and "cargo:rustc-link-search" directives, see Build Scripts documentation.