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Basic utilities for dealing with memory, values, and types. > + > +use crate::prelude::*; > + > +/// Transmute between two types. > +/// > +/// Use this instead of [`core::mem::transmute`] when it is known that s= izes are identical but this > +/// cannot be proven by the compiler. > +/// > +/// This is equivalent to Rust's `transmute_unchecked` intrinsics. > +/// > +/// # Safety > +/// > +/// All safety requirements of [`core::mem::transmute`] apply, plus that= the size `Src` and `Dst` > +/// must match. > +/// > +/// # Example nit: IIUC the convention is to always use the plural `Examples`. > +/// > +/// This can be used when types are known to have the same size, but onl= y at runtime. > +/// ```no_run > +/// # use core::any::TypeId; > +/// fn to_u32(v: T) -> Option { > +/// if TypeId::of::() !=3D TypeId::of::() { > +/// return None; > +/// } > +/// > +/// // `core::mem::transmute` won't work here. > +/// // SAFETY: We've checked that `T` is u32! > +/// Some(unsafe { kernel::mem::transmute_unchecked(v) }) > +/// } > +/// > +/// to_u32(1u32); Missing closing code block here - interestingly, without it this block triggers a "function has unnecessary safety comment" warning. With this, Reviewed-by: Alexandre Courbot