Is this code safe?

use std::marker::PhantomData;
struct Foo<T> {
    bar: u8,
    baz: PhantomData<T>,
}
impl<T> Foo<T> {
    fn new(bar: u8) -> Self {
        Self { bar, baz: PhantomData }
    }
}

fn main() {
    let v = Foo::<&mut i32>::new(4);
    let x = unsafe {
        // don't focus on i32 and bool, I've chosen two random types
        std::mem::transmute::<Foo<&mut i32>, Foo<&mut bool>()
    };
}

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