On Fri, Nov 15, 2024 at 03:00:43PM +0100, Alice Ryhl wrote: > On Fri, Nov 15, 2024 at 12:33 PM Asahi Lina <lina@xxxxxxxxxxxxx> wrote: > > > > We (Asahi Linux) noticed that this doesn't support unsized types, which > > is a regression from the alloc Box. drm/asahi uses boxed trait objects > > to generalize across certain object types like render commands, so this > > breaks the driver. > > > > Is there a plan to add this back in? AIUI this would need the > > coerce_unsized unstable feature, but is there any other blocker? > > We're already using coerce_unsized for Arc, so I see no reason we > can't just add that for KBox too. Soon, we should be able to use the > derive macro [1] I proposed to do this without unstable language > features. The limitation that the RFC mentions for custom allocators > does not apply to KBox because it uses PhantomData<A> instead of A for > the allocator field. I have branch rebased onto rust-next and Danilo's "Device / Driver PCI / Platform Rust abstractions". In addition to coerce_unsized for kbox kvec misses the unproblematic methods clear and truncate and array_try_from_vec. drain() as taken from the rust library looks like more effort considering kvec's IntoIter. Janne
