[dwattttt]

Nope, it wouldn't be. I'm just pointing out that it being unsafe or hard to use is no barrier at all to it being in the language.

[masklinn]

Hell, since RAII is an opt-in type-level infectious (in the sense that if you have an RAII member in a struct the struct is RAII) mechanism you can require that RAII structs be initialised.

Given the compiler would already need to know that a local is of an RAII type in order to insert the drop, move, and copy glues it’s not exactly a big requirement.