On 27/02/2023 22.09, Andreas Hindborg wrote: > > Asahi Lina <lina@xxxxxxxxxxxxx> writes: > >> The unstable new_uninit feature enables various library APIs to create >> uninitialized containers, such as `Box::assume_init()`. This is >> necessary to build abstractions that directly initialize memory at the >> target location, instead of doing copies through the stack. >> >> Will be used by the DRM scheduler abstraction in the kernel crate, and >> by field-wise initialization (e.g. using `place!()` or a future >> replacement macro which may itself live in `kernel`) in driver crates. >> >> See [1] [2] [3] for background information. >> >> [1] https://github.com/Rust-for-Linux/linux/issues/879 >> [2] https://github.com/Rust-for-Linux/linux/issues/2 >> [3] https://github.com/rust-lang/rust/issues/63291 >> >> Signed-off-by: Asahi Lina <lina@xxxxxxxxxxxxx> >> --- >> rust/kernel/lib.rs | 1 + >> scripts/Makefile.build | 2 +- >> 2 files changed, 2 insertions(+), 1 deletion(-) >> >> diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs >> index 223564f9f0cc..1118cd3e0b5f 100644 >> --- a/rust/kernel/lib.rs >> +++ b/rust/kernel/lib.rs >> @@ -17,6 +17,7 @@ >> #![feature(core_ffi_c)] >> #![feature(dispatch_from_dyn)] >> #![feature(generic_associated_types)] >> +#![feature(new_uninit)] >> #![feature(receiver_trait)] >> #![feature(unsize)] >> >> diff --git a/scripts/Makefile.build b/scripts/Makefile.build >> index a0d5c6cca76d..0f637e1ca8dc 100644 >> --- a/scripts/Makefile.build >> +++ b/scripts/Makefile.build >> @@ -277,7 +277,7 @@ $(obj)/%.lst: $(src)/%.c FORCE >> # Compile Rust sources (.rs) >> # --------------------------------------------------------------------------- >> >> -rust_allowed_features := core_ffi_c >> +rust_allowed_features := core_ffi_c,new_uninit > > What is the purpose of adding the feature here? The kernel crate seems > to compile fine without this. It's for the upcoming DRM abstractions, as I mentioned in the commit message. There's so many dependencies that I'm trying to get as much as I can early to avoid having to review very big patchsets down the line ^^ ~~ Lina
