Error when writing Rust code in Doom Emacs

Hello, I'm extremely new to Emacs. I'm currently using Doom Emacs and writing some Rust code. I enabled the rust under :lang in the init.el file for doom. Whenever my cursor is on a line of code, I get the following error at the bottom of the screen: eldoc error: (user-error No such directory: /usr/local/src/rust/src. Please set 'racer-rust-src-path' or 'RUST\_SRC\_PATH'. Why am I seeing this error, and how can I solve it? Edit: so I found out that racer rust isn't even an updated syntax checker. I think it's recommended to switch to rust-analyzer. So I commented out rust in my init.el and resynced doom, which got rid of the racer rust error. I then installed the rustic package by including it in my package.el and resyncing doom. I also had the rust-analyzer package installed from my distro's repository before doing so. I then opened up my rust project and saw an error that said Cargo was not found because it wasn't in the PATH. I added cargo to the Emacs PATH and exec-path, and it finally worked.

I guess you have to install Rust source code in order to make LSP work. If you used rustup you can install it with: ``` rustup componeng add rust-src ```. Otherwise, if you are on Ubuntu you can install it with: ``` apt install rust-src ```. On other distros it should be similiar.