Swift C++ interop. How to check a returned shared_ptr is nil

Using Swift
1

C++

std::shared_ptr FSOCache::copyPtr(const std::string& path) {
  std::lock_guard<std::mutex> guard(cacheMutex);
  auto it = cache.find(path);
  if (it == cache.end()) {
    return nullptr;
  }

  auto p = std::make_shared<FSObject>(it->second);
  return p;
}

std::shared_ptr FSOManager::getFSO(const std::string& path) {
  auto fso = fsoCache.copyPtr(path);
  return fso;
};

Swift

var m = FSOManager()
let cxxp = std.string(somePath)
var fsoPtr = m.getFSO(cxxp)
if fsoPtr == nil {

}

Using if fsoPtr == nil {} gives the warning 'Comparing non-optional value of type 'std.__1.shared_ptr' to 'nil' always returns false'.

fsoPtr.pointee does not return a pointer.