contacts.sol

pragma solidity 0.8.17;

contract Contract1 {
    Contract2 public contract2;

    constructor() {
        contract2 = new Contract2(address(this));
    }

    function foo() public pure returns (string memory) {
        return "bar";
    }
}

// In this case it fails
contract Contract2 {
    Contract1 contract1;

    constructor(address _contract1) {
        contract1 = Contract1(_contract1);
        contract1.foo();
    }
}

// In this case everything works fine
contract Contract2 {
    Contract1 contract1;

    constructor(address _contract1) {
        contract1 = Contract1(_contract1);
    }

    function bar() public view returns(string memory) {
        return contract1.foo();
    }
}