[yyyk]

Right, it depends on how far one wants to go to avoid allocations. structs and spans are safe. But one can go even deeper and pin pointers and do Unsafe.AsPointer and get a de-facto (unsafe) union out of it....

>https://em-tg.github.io/csborrow/

Oooh... I didn't know scoped refs existed.

[int_19h]

If you want an unsafe union, that's what StructLayout.Explicit and FieldOffset is for - a struct with all fields placed at offset 0 is exactly the same as a C union.