fn spawn_and_join<F>(f: F)
    where
        F: FnOnce(),
        F: Send + 'static,
    {
        f();
    }
// MIRI does not support threads, so just execute sequentially.
MIRI does not support threads, so just execute sequentially.
MIRI does not support threads so just execute sequentially .
fn spawn_and_join<F>(f: F)
    where
        F: FnOnce(),
        F: Send + 'static,
    {
        f();
    }
fn spawn_and_join < F > ( f : F ) where F : FnOnce ( ) , F : Send + ' static , { f ( ) ; }
MIRI does not support threads, so just execute sequentially.
MIRI does not support threads so just execute sequentially .
f
F