>
> For example:
>
> ```
> auto *p = operator new(1);
> auto *pc = new(p) char;
> delete pc;
> ```
>
> That delete is invalid, and it *should be*. If you use two-step object
> creation (allocate memory, then put an object into it), you should use
> two-step object destruction (destroy the object, then deallocate the
> memory).
>

In fact, it is legal. The standard does not specify that a new-expression
cannot be a placement-new.

The standard should not forbid some code that is not very good, but correct.