message: We only need to update the ptr if we are re-allocating
diff: @@ -75,9 +75,9 @@ public:
  if (new_size > alloc_len) {
  alloc_len = new_size;
  allocated_data = allocator.Allocate(alloc_len);
  - }
  ptr = (char *)allocated_data->get();
  }
  + }
  private:
  unique_ptr<AllocatedData> allocated_data;
  