The cleanest approach is to relocate (trivial relocatability was delayed for after C++26) the object into nothing. That would probably just destruct it, but the compiler would know, not to destruct it a second time. Moving has to keep the object in a valid state. Calling the destructor would probably lead to double-destruction. -----Ursprüngliche Nachricht----- Von:SD SH <Z5515zwy_at_[hidden]> Gesendet:Sa 13.12.2025 02:20 Betreff:Re: [std-proposals] 回复: 回复: 回复: [PXXXXR0] Add a New Keyword ‘undecl’ An:std-proposals_at_[hidden]; CC:Sebastian Wittmeier <wittmeier_at_[hidden]>; Thinking of more cases, we can move the object, call the destructor, use std::destroy_at or just do nothing until it end, so changing lifetimes is not necessary and it will introduce trouble in managing a object.