What is the reason for passing props to super() in a React constructor when props aren't accessed within it?

Question

I've seen many code snippets such as HelloWorld, where props is passed to super(). What is the reason to do that when this.props is not accessed in the constructor?

class HelloWorld extends Component {
    constructor(props) {
        super(props);

        this.state = { message: 'Hi' };
        this.logMessage = this.logMessage.bind(this);
    }

    logMessage() {
        console.log(this.state.message);
    }

    render() {
        return (
            <input type="button" value="Log" onClick={this.logMessage} />
        );
    }
}

Answer 1

The constructor for a React component is called before it is mounted. When implementing the constructor for a React component subclass, you should call super(props) before any other statement. Otherwise, this.props will be undefined in the constructor, which can lead to bugs.

Read Here for more details.