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I'm writing my own rust wrapper for the library GLFW. In this library the GLFWwindow type has the ability to store a pointer of type *mut c_void of any arbitrary user data.
I've decided that in my case this pointer should store a mutable reference to dyn Any.

pub fn set_data<T>(&self, data: &mut T)
where
     T: any::Any + 'static,
{
    let as_ref = data as &mut (dyn any::Any + 'static);
    dbg!(as_ref.type_id());
    let ptr = as_ref as *mut dyn any::Any;
    unsafe {
        // raw: NonNull<GLFWwindow>,
        glfw_rs_sys::glfwSetWindowUserPointer(self.raw.as_ptr(), ptr.cast());
    }
}

pub fn get_data<T>(&self) -> Option<&mut T>
where
      T: any::Any + 'static,
 {
     let ptr = unsafe { glfw_rs_sys::glfwGetWindowUserPointer(self.raw.as_ptr()) }
         as *mut dyn any::Any;
     let as_mut = unsafe { ptr.as_mut() };
     match as_mut {
         Some(reference) => {
             dbg!(reference.type_id());
             reference.downcast_mut()
         }
         None => None,
     }
}

Example usage:

llet mut user_data = 10.0_f64;
window.set_data(&mut user_data);
let got = window.get_data::<f64>();
println!("{got:?}");

But when you run this example, it prints this:

[glfw-test/src/window.rs:131:9] as_ref.type_id() = TypeId(0xc45c25bfe577a84e0b073a6684adcb7c)
[glfw-test/src/window.rs:147:17] reference.type_id() = TypeId(0xd8beda7b1917692422de15bb4429a07f)
None

Is this a bug or am I missing something?
Also I know that get_data shouldn't just return a mutable reference, this code is just a prototype currently

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