function handleLoss( uint256 gvtAssets, uint256 pwrdAssets, uint256 loss) private pure returns (uint256, uint256) {
        uint256 maxGvtLoss = gvtAssets.sub(DEFAULT_DECIMALS_FACTOR);
        if (loss > maxGvtLoss) {
          ...
        } else {
            gvtAssets = gvtAssets - loss;    // won't underflow but safemath won't hurt
        }

    function forceDistribute() private {
        uint256 total = _controller().totalAssets();
        if (total > lastPwrdAssets.add(DEFAULT_DECIMALS_FACTOR)) {
            lastGvtAssets = total - lastPwrdAssets;   // won't underflow but safemath won't hurt
        } else {
   ...
function distributeStrategyGainLoss(uint256 gain, uint256 loss) external override {
    uint256 index = vaultIndexes[msg.sender];
    require(index > 0 || index <= N_COINS + 1, "!VaultAdaptor");    // always true, see separate issue
    ..
    index = index - 1;  // can underflow
