Snowman Merkle Airdrop

[Low] Redundant Error Declaration Snowman.sol::SM__NotAllowed (Unused Code + Extra Bytecode Size)

Description

The custom error SM__NotAllowed() is declared within the Snowman.sol contract but is never invoked or reverted by any function throughout the contract's codebase.

Risk

While not a direct security vulnerability, unused code, including error declarations, contributes to a marginally larger contract bytecode size. This incurs a minor, unnecessary gas cost during contract deployment. Additionally, it can reduce code clarity, potentially misleading auditors or developers into searching for its usage or assuming an unimplemented access control check.

Proof of Concept

A static analysis or a simple search within the Snowman.sol file confirms that SM__NotAllowed() is declared but has no corresponding revert statement anywhere in the contract logic.

Recommended Mitigation

Remove the unused error declaration to improve code clarity, reduce the contract's bytecode size, and streamline the codebase.