Example programme does not run: 32-bit ystem

[worikgh]

I tried to compile the programme from here. I expect the problem is that I am on a 32-bit system

error[E0308]: mismatched types                                                                                                                                           
   -->~/.cargo/registry/src/github.com-1285ae84e5963aae/rtmidi-0.2.0/src/midi_in.rs:185:74
    |
185 |         let timestamp = unsafe { ffi::rtmidi_in_get_message(self.0, ptr, &mut length) };
    |                                  --------------------------              ^^^^^^^^^^^ expected `u32`, found `u64`
    |                                  |
    |                                  arguments to this function are incorrect
    |
    = note:    expected raw pointer `*mut u32`
            found mutable reference `&mut u64`