typename Allocator = std::allocator<uint8_t>,
template <typename> class Atom = std::atomic,
class Mutex = std::mutex>
-class FOLLY_ALIGNED(64) ConcurrentHashMapSegment {
+class alignas(64) ConcurrentHashMapSegment {
enum class InsertType {
DOES_NOT_EXIST, // insert/emplace operations. If key exists, return false.
MUST_EXIST, // assign operations. If key does not exist, return false.