Invalid Warning: This looks like an address but has an invalid checksum

[ruchevits]

contract Users {
  struct User {
    address addr;
    string name;
  }
  mapping (bytes32 => User) users;
  function create(bytes32 id, string name) {
    users[id] = User(msg.sender, name);
  }
}

I'm getting the following error trying to compile it:

Warning: This looks like an address but has an invalid checksum. If this is not used as an address, please prepend '00'.

It looks like an address because it is an address. And it is used as an address.

[federicobond]

I cannot reproduce this with latest master or browser-solidity. Which version of solidity are you using?

[ruchevits]

solc 0.4.10

[chriseth]

@ruchevits if you use literal addresses, you have to use the uppercase / lowercase encoding. This error might also come from the --libraries option to solc and not necessarily from the source code itself.

[ruchevits]

@chriseth @federicobond Sorry, my mistake, the error actually happens with:

contract Users {
  struct User {
    address addr;
    string name;
  }
  mapping (bytes32 => User) users;
  function create(bytes32 id, string name) {
    address myAddr = 0x0E5CB767CCE09A7F3CA594DF118AA519BE5E2B5A;
    users[id] = User(myAddr, name);
  }
}

(when the address is hardcoded)

If I wrap the address in double quotes, the error is: Error: Type literal_string "0x0E5CB767CCE09A7F3CA594DF118AA519BE5E2B5A" is not implicitly convertible to expected type address.

address myAddr = "0x0E5CB767CCE09A7F3CA594DF118AA519BE5E2B5A";

If I try to explicitly cast literal string to address, the error is: Error: Explicit type conversion not allowed.

address myAddr = address("0x0E5CB767CCE09A7F3CA594DF118AA519BE5E2B5A");

[chriseth]

The warning asks you to add a checksum to your address: ethereum/EIPs#55

[ruchevits]

@chriseth Thank you!

[ronnie173]

So how exactly did you fix this? Can you please post an example? Because I tried everything

[axic]

Just follow what the compiler suggests - it also suggests you the correctly encoded address. Note: the distinction between lower and uppercase letters matters.

[CHAOWEICHIU]

I had the same issue, but you can make it work by using ethereumjs-util
const { toChecksumAddress } = require('ethereumjs-util')
The address I had was
0x8a9a728f64e58db7e790f099bddb3416ccc2eb77
by using toChecksumAddress() I get
0x8a9a728f64E58Db7e790F099BdDB3416ccC2Eb77

For how they did it, please refer to
https://github.com/ethereumjs/ethereumjs-util/blob/master/index.js#L476