"constants" expressions are expressions, not constants. Use "immutable" instead.

[code423n4]

Handle

Dravee

Vulnerability details

Impact

Due to how constant variables are implemented, an expression assigned to a constant variable is recomputed each time that the variable is used, which wastes some gas.

If the variable was immutable instead: the calculation would only be done once at deploy time (in the constructor), and then the result would be saved and read directly at runtime rather than being recalculated.

See: ethereum/solidity#9232

Proof of Concept

Timeswap-V1-Convenience\contracts\libraries\DateTime.sol:31:    uint constant SECONDS_PER_DAY = 24 * 60 * 60;
Timeswap-V1-Convenience\contracts\libraries\DateTime.sol:32:    uint constant SECONDS_PER_HOUR = 60 * 60;

Tools Used

VS Code

Recommended Mitigation Steps

Change these expressions from constant to immutable and implement the calculation in the constructor

[Mathepreneur]

Timeswap-Labs/Timeswap-V1-Convenience#62