Since C++20, std::memory_order is defined as an enum class so requires explicit casting to an int when adding enum values. See https://en.cppreference.com/w/cpp/atomic/memory_order.
Since C++20, std::memory_order is defined as an enum class so requires explicit casting to an int when adding enum values. See https://en.cppreference.com/w/cpp/atomic/memory_order.