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Unchecked Return Values

What it detects​

When calling external contracts, ignoring the success flag or return value can hide failures. This detector points out low-level call or ERC20 transfer returns that are not checked, potentially leading to inconsistent state.

Typical symptoms​

  • Results of call, delegatecall, or token transfers unused
  • No require statement for the returned boolean

Solidity snippet (v0.8.25)​

pragma solidity ^0.8.25;

contract NoCheck {
    function sendEther(address payable to) external {
        // Return value ignored
        to.call{value: 1 ether}("");
    }
}

Why it matters on EVM​

Unchecked return values can cause silent failures, leaving contracts in unexpected states or losing funds.