warning: field `rebuild` is never read
  --> check/src/project.rs:33:9
   |
30 | pub struct BuildConfig {
   |            ----------- field in this struct
...
33 |     pub rebuild: bool,
   |         ^^^^^^^
   |
   = note: `BuildConfig` has a derived impl for the trait `Clone`, but this is intentionally ignored during dead code analysis
   = note: `#[warn(dead_code)]` on by default