In addition to illegal operations, transferring TRX/TRC10 to non-existent accounts also incurs a full penalty of the fee_limit. As users normally set the fee limit to 1000 TRX (max), this is a significant penalty and can be even more costly if the user attempts to retry the operations automatically.

Penalized Contracts Examples

Transferring TRX into a Non-Existent/Invalid Account

pragma solidity ^0.4.23;

contract Invalid {

  function transAddr() public payable {
    address invalid = 0x1234aabb;
    invalid.transfer(10 trx);
  }
  
  function transAddr2(address addr) public payable {
    addr.transfer(10 trx);
  }
}

In the above example, transAddr always fails and consumes the fee_limit. In the more common case of transAddr2, the developer should make sure addr is pre-validated in either Tron-Web or some other existing address. Otherwise, the user pays for the fee_limit penalty.

Transferring TRX into Itself

pragma solidity ^0.4.23;

contract Self {

  function transAddr() public payable {
    address(this).transfer(10 trx);
  }

  function transAddr2(address addr) public payable {
    addr.transfer(10 trx);
  }

  function transAddr3(address addr) public payable {
    require(addr != address(this));
    addr.transfer(10 trx);
  }
}

Similarly, transAddr always incurs the fee_limit penalty. transAddr2 will fail the self-transfer case if addr is the contract's address itself. transAddr3 protects against the self-transfer penalty but still suffers from the non-existent account problem above.

TRC10 Token Transfer into a Non-Existent/Invalid Account

pragma solidity ^0.4.24;

contract TRC10 {

  function sendBalance(address to) public payable {
    trcToken id = msg.tokenid;
    uint256 value = msg.tokenvalue;
    to.transferToken(value, id);
  }

  function sendBalance2() public payable {
    trcToken id = msg.tokenid;
    uint256 value = msg.tokenvalue;
    address(this).transferToken(value, id);
  }
}

Similar to the TRX transfer above, if to account does not exist, sendBalance fails with a fee_limit penalty. The self-transfer case sendBalance2 also incurs fee_limit.