GStreamer log handler can get objects passed that are not fully constructed yet (e.g. instance_init) and have no name

I'm trying to port libgstreamer_android.so's initialization code to rust. See my project androidsink at github.

The initialization crashes at the get_name in the following place while creating an element of audiotestsrc:

                    let ob = obj.downcast_ref::<gst::Object>().unwrap();
                    let name = ob.get_name().to_string();

I printed the ob with {:?}, found it to be an Object { inner: ObjectRef { inner: 0x9ea53898, type: GstBaseSrc } }.

Any hint for me to fix it?