        bool success;

        // call the conduit.
        assembly {
            // Ensure first word of scratch space is empty.
            mstore(0, 0)

            // Perform call, placing first word of return data in scratch space.
            success := call(
                gas(),
                conduit,
                0,
                callDataOffset,
                callDataSize,
                0,
                OneWord
            )
        }

        // <--- If the compiler changes scratch space after this (or even in the helpers below) then it will fail.

        // If the call failed...
        if (!success) {
            // Pass along whatever revert reason was given by the conduit.
            _revertWithReasonIfOneIsReturned();

            // Otherwise, revert with a generic error.
            revert InvalidCallToConduit(conduit);
        }

        // Ensure that the conduit returned the correct magic value.
        bytes4 result;
        assembly {
            // Take value from scratch space and place it on the stack.
            result := mload(0)
        }

        // Ensure result was extracted and matches EIP-1271 magic value.
        if (result != ConduitInterface.execute.selector) {
            revert InvalidConduit(conduitKey, conduit);
        }
