message: equality operators for cuda_managed_allocator
diff: @@ -837,6 +837,9 @@ public:
  void deallocate(value_type *ptr, size_t) {
  cuda_free(ptr);
  }
  +
  + bool operator==(const cuda_managed_allocator &) { return true; }
  + bool operator!=(const cuda_managed_allocator &) { return false; }
  };
  #if defined(ENOKI_AUTODIFF) && !defined(ENOKI_BUILD)
  