From 8909a80e3f684fb274a171489c16e8f10c482e83 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Tue, 6 Dec 2022 02:05:19 +0100 Subject: rust: alloc: remove the `borrow` module (`ToOwned`, `Cow`) The `Cow` type [1] requires that its generic parameter type implements the `ToOwned` trait [2], which provides a method to create owned data from borrowed data, usually by cloning. However, it is infallible, and thus in most cases it is not useful for the kernel. [3] Therefore, introduce `cfg(no_borrow)` to remove the `borrow` module (which contains `ToOwned` and `Cow`) from `alloc`. Link: https://doc.rust-lang.org/alloc/borrow/enum.Cow.html [1] Link: https://doc.rust-lang.org/alloc/borrow/trait.ToOwned.html [2] Link: https://lore.kernel.org/rust-for-linux/20221204103153.117675b1@GaryWorkstation/ [3] Cc: Gary Guo Cc: Wedson Almeida Filho Cc: Josh Triplett Signed-off-by: Miguel Ojeda Reviewed-by: Wei Liu Reviewed-by: Finn Behrens --- rust/alloc/lib.rs | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'rust/alloc/lib.rs') diff --git a/rust/alloc/lib.rs b/rust/alloc/lib.rs index 233bcd5e4654..3aebf83c9967 100644 --- a/rust/alloc/lib.rs +++ b/rust/alloc/lib.rs @@ -100,7 +100,7 @@ #![cfg_attr(not(no_global_oom_handling), feature(const_alloc_error))] #![feature(const_box)] #![cfg_attr(not(no_global_oom_handling), feature(const_btree_new))] -#![feature(const_cow_is_borrowed)] +#![cfg_attr(not(no_borrow), feature(const_cow_is_borrowed))] #![feature(const_convert)] #![feature(const_size_of_val)] #![feature(const_align_of_val)] @@ -215,6 +215,7 @@ pub mod boxed; mod boxed { pub use std::boxed::Box; } +#[cfg(not(no_borrow))] pub mod borrow; pub mod collections; #[cfg(not(no_global_oom_handling))] -- cgit v1.2.3-70-g09d2