Garbage collector crashes on mark/drain of generator functions

import QtQuick 2.15
import QtQuick.Window 2.15
import QtQuick.Controls 2.2
Window {
    width: 100
    height: 100
    visible: true    

    Component {
        id: textComp
        Item {
            property var gen: (function*(){ yield 42; })()
            Component.onCompleted: {
                gc() // tries to cleanup old object, but crashes with 'gen'
            }
        }
    } 
   
    Column {
        anchors.fill: parent
        StackView {
            id: stack
            width: 100
            height: 100
            initialItem: Item { }
        }        
        Button {
            height: 50
            width: 100
            text: "Click"
            onClicked:  {
                if(stack.depth > 1)
                    stack.pop()
                stack.push(textComp)
            }
        }
    }
}