1 error: calling `Mutex::lock` inside the scope of another `Mutex::lock` causes a deadlock
2 --> $DIR/if_let_mutex.rs:9:5
4 LL | / if let Err(locked) = m.lock() {
5 LL | | do_stuff(locked);
7 LL | | let lock = m.lock().unwrap();
12 = note: `-D clippy::if-let-mutex` implied by `-D warnings`
13 = help: move the lock call outside of the `if let ...` expression
15 error: aborting due to previous error