fn main() { println!( "cargo:rustc-env=BUILD_TARGET={}", std::env::var("TARGET").unwrap() ); println!( "cargo:rustc-env=BUILD_HOST={}", std::env::var("HOST").unwrap() ); let emscripten_version = std::fs::read_to_string("emscripten-version").unwrap(); println!( "cargo:rustc-env=EMSCRIPTEN_VERSION={}", emscripten_version.trim() ); }