error: initializer for `thread_local` value can be made `const` --> tests/flags.rs:117:64 | 117 | static VERBOSE_LOGS: RefCell<Option<Sender<String>>> = RefCell::new(None); | ^^^^^^^^^^^^^^^^^^ help: replace with: `const { RefCell::new(None) }` | = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#thread_local_initializer_can_be_made_const = note: `-D clippy::thread-local-initializer-can-be-made-const` implied by `-D warnings` = help: to override `-D warnings` add `#[allow(clippy::thread_local_initializer_can_be_made_const)]`