error: initializer for `thread_local` value can be made `const`
   --> tracing-subscriber/src/fmt/fmt_layer.rs:946:43
    |
946 |             static BUF: RefCell<String> = RefCell::new(String::new());
    |                                           ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: replace with: `const { RefCell::new(String::new()) }`
    |
    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#thread_local_initializer_can_be_made_const

error: initializer for `thread_local` value can be made `const`
   --> tracing-subscriber/src/registry/sharded.rs:217:39
    |
217 |     static CLOSE_COUNT: Cell<usize> = Cell::new(0);
    |                                       ^^^^^^^^^^^^ help: replace with: `const { Cell::new(0) }`
    |
    = 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)]`