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Rounding Errors

What it detects​

This detector finds integer division or modulo operations where the remainder is silently truncated. Contracts that expect fractional values can misbehave when precision is lost.

Typical symptoms​

  • Calculations yield smaller results than expected
  • Percentage math using integers looks off

Solidity snippet (v0.8.25)​

pragma solidity ^0.8.25;

contract RoundingDemo {
    function divide(uint256 a, uint256 b) external pure returns (uint256) {
        // Precision loss if 'b' doesn’t divide 'a' exactly
        return a / b;
    }
}

Why it matters on EVM​

Rounding errors accumulate over time, leading to financial discrepancies or drained reserves in DeFi protocols.