Does cargo cache the result of typechecking?

My IDE runs cargo check automatically after I make some changes. Assuming it checks, does it do the typechecking again after I cargo run?

Asking this as a game dev where incremental compile time is very important.

It does.

Cargo has an incremental cache, but last time I checked it wasn't reused between check and run. rust-analyzer has its own separate type checking too.


cargo build --timings

it will generate a report of everything that took time during compilation.

There's also a way to check more detailed time:

RUSTFLAGS=-Ztime-passes cargo +nightly build

and this contains separate passes for type checking, so you can verify if your project has a degenerate case where type checking takes disproportionally long time (usually it's tiny, and LLVM and linker take the most time in incremental rebuild).

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