Now I am developing a feature for cpal, and it contains a target for emscripten
I follow the document https://rust-analyzer.github.io/book/configuration.html#cargo.target and set the target to wasm32-unknown-emscripten, and then the relative codes are uncommented, but still I cannot complete any things, and relative codes are all red

https://github.com/RustAudio/cpal/blob/master/Cargo.toml
code is here
How should I do?