On 11/09/2025 2:31 AM, IchorDev wrote:
On Wednesday, 10 September 2025 at 13:13:34 UTC, Richard (Rikki) Andrew
Cattermole wrote:
The reason placement new is @system is because of double-init. It
can't be a safe operation.
What?! Like, it assigns to the memory twice? What's the point of this
feature, then? I thought this could essentially replace `emplace` for
constructing types into uninitialised memory, but instead it's just a
booby-trap that stops people from making their code `@safe`?
It does replace emplace, and just like emplace you can double-init
memory with it. There is no protection against it apart from it being
@system (which emplace should also be).
The caller is responsible for guaranteeing that the memory passed in is
uninitialized, and that behavior is @system.
