I think it can work on pointers to (an array of) non-trivially-destructible
objects. Maybe nobody finds a real usage scenario for this, thus no one has
proposed it?

On Tue, 14 Apr 2026 at 16:47, Marcin Jaczewski via Std-Discussion <
std-discussion_at_[hidden]> wrote:

> If I have a pointer that I can call `delete[]` on it, then why does
> the standard not allow
> getting the size of this storage aside in case of deleting it?
> like:
>
> ```
> auto* p = new Foo[100]{};
> auto size = std::get_allocated_elements(p);
> delete[] p;
> assert(size == 100);
> ```
>
> Only case where I could see this not working is `new char[]` as it could
> skip
> this metadata as no destructor call is needed for elements.
>
> There are other limitations that prevent the standard to have it?
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-- 
Yongwei Wu
URL: http://wyw.dcweb.cn/