Alchemix contest - hake's results

NON-CRITICAL

N-01: safeApprove has been deprecated

StrategyController.sol#L499

Consider using safeIncreaseAllowance and safeDecreaseAllowance instead.

REFERENCE

N-02: Floating Pragma

Using a floating pragma (^) might result in the contract being deployed with a version it was not tested with and might result in bugs that affect the contract system negatively.

Locking the pragma (deleting the ^) helps to ensure that contracts do not accidentally get deployed using an outdated compiler version or a version it was not tested with.

GAS

G-01: for loop gas optimization

https://github.com/code-423n4/2022-05-alchemix/blob/de65c34c7b6e4e94662bf508e214dcbf327984f4/contracts-full/StakingPools.sol#L363

for (uint256 _poolId = 0; _poolId < _pools.length(); _poolId++) {
    Pool.Data storage _pool = _pools.get(_poolId);
    _pool.update(_ctx);
}

Gas could be saved by:

• Not initializing variable to default value of zero
• Caching array length
• Using a prefix (++i) instead of a postfix (i++)
• Unchecking increment count

Example:

uint size = _pools.length();
for (uint256 _poolId; _poolId < size;) {
    Pool.Data storage _pool = _pools.get(_poolId);
    _pool.update(_ctx);

    unchecked { ++_poolId; }
}

Other instances: https://github.com/code-423n4/2022-05-alchemix/blob/de65c34c7b6e4e94662bf508e214dcbf327984f4/contracts-full/AlchemistV2.sol#L990 https://github.com/code-423n4/2022-05-alchemix/blob/de65c34c7b6e4e94662bf508e214dcbf327984f4/contracts-full/AlchemistV2.sol#L1282 https://github.com/code-423n4/2022-05-alchemix/blob/de65c34c7b6e4e94662bf508e214dcbf327984f4/contracts-full/AlchemistV2.sol#L1355 https://github.com/code-423n4/2022-05-alchemix/blob/de65c34c7b6e4e94662bf508e214dcbf327984f4/contracts-full/AlchemistV2.sol#L1461 https://github.com/code-423n4/2022-05-alchemix/blob/de65c34c7b6e4e94662bf508e214dcbf327984f4/contracts-full/AlchemistV2.sol#L1524 https://github.com/code-423n4/2022-05-alchemix/blob/de65c34c7b6e4e94662bf508e214dcbf327984f4/contracts-full/EthAssetManager.sol#L214

G-02: _checkState is redundant

AlchemistV2.sol#L1740

_uadd and _sub methods are redudant as there no risk of overflowing in the current contract implementation.