What's the safest way to remove an admin from an existing open zepplin ERC20 token?

Question

Lets say you have this erc20 token already made, what's the safest way to no longer allow the mint and burn functions to work? Is there a better solution than creating a smart contract, updating the token admin to that contract, then using the selfdestruct() function to render that contract useless?

Here's code:

import '@openzeppelin/[email protected]/token/ERC20/ERC20.sol';

contract Token is ERC20 {
  address public admin;

  constructor(string memory name, string memory symbol) ERC20(name, symbol) {
    admin = msg.sender;
  }

  function updateAdmin(address updateadmin) external {
    require(msg.sender == admin, 'only admin');
    admin = updateadmin;
  }

  function mint(address to, uint amount) external {
    require(msg.sender == admin, 'fail, admin only');
    _mint(to, amount);
  }

  function burn(address owner, uint amount) external {
    require(msg.sender == admin, 'fail, admin only');
    _burn(owner, amount);
  }

}

Answer 1

If you're sure you want to revoke admin privileges, you can call updateAdmin() with the zero address, essentially burning that role forever. As you can see on Etherscan, the zero address was often used as a "burn" address.

Keep in mind this is unrecoverable if you do it!