Interesting solidity snippets and puzzles from Extropy

Given that, it shouldn't be difficult for you to work out what this bytecode is doing.

6080604052348015600f57600080fd5b5060003090508073ffffffffffffffffffffffffffffffffffffffff16fffe

Solution and discussion

Here is the solidity code for the contract, it simply self destructs when deployed.

// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.13;
contract Marvin {
constructor() {
address payable addr = payable(address(this));
selfdestruct(addr);
}
}

Interestingly if we add more solidity to the contract, for example

// SPDX-License-Identifier: UNLICENSED
pragma solidity ^0.8.13;
contract Marvin {
constructor() {
address payable addr = payable(address(this));
selfdestruct(addr);
}
function someOtherFunction() public view returns (uint256) {
return address(this).balance;
}
}

The bytecode remains the same, the compiler is intelligent enough to ignore the rest of the contract since it could never be used.

The init code part of the bytecode doesn't do the usual code copy to memory, presumably for the same reason. It does still set up the free memory pointer, which is not needed however.

Marvin

As a child I was fascinated by machines whose whole purpose, when switched on, was to turn themselves off.

Given that, it shouldn't be difficult for you to work out what this bytecode is doing.

Here is the solidity code for the contract, it simply self destructs when deployed.

Interestingly if we add more solidity to the contract, for example

The bytecode remains the same, the compiler is intelligent enough to ignore the rest of the contract since it could never be used.

The init code part of the bytecode doesn't do the usual code copy to memory, presumably for the same reason. It does still set up the free memory pointer, which is not needed however.

Another interesting point is that we are allowed to use this contract's address as the destination for ETH after the self destruct.