unchecked { ++i } is more gas efficient than i++ for loops

[code423n4]

Handle

GiveMeTestEther

Vulnerability details

Impact

The loop index increments can be written as unchecked { ++i } instead of simply i++ to save gas.
Two reasons:

• unchecked because the loop variable i is of type uint256, therefore we would run out of gas before triggering an overflow
• ++i instead of i++ because it is slightly more efficient

Proof of Concept

see discussion here ethereum/solidity#10695

Tools Used

Visual Code Studio

Recommended Mitigation Steps

replace i++ with unchecked { ++i }

[adrien-supizet]

As already discussed here in another audit code-423n4/2021-10-pooltogether-findings#6 (comment)

We are not going to fix this as it reduces clarity