On Sat, Feb 17, 2024 at 1:27 AM Miguel Ojeda <ojeda@xxxxxxxxxx> wrote:
>
> This is the next upgrade to the Rust toolchain, from 1.75.0 to 1.76.0
> (i.e. the latest) [1].
>
> See the upgrade policy [2] and the comments on the first upgrade in
> commit 3ed03f4da06e ("rust: upgrade to Rust 1.68.2").
>
> # Unstable features
>
> No unstable features that we use were stabilized in Rust 1.76.0.
>
> The only unstable features allowed to be used outside the `kernel` crate
> are still `new_uninit,offset_of`, though other code to be upstreamed
> may increase the list.
>
> Please see [3] for details.
>
> # Required changes
>
> `rustc` (and others) now warns when it cannot connect to the Make
> jobserver, thus mark those invocations as recursive as needed. Please
> see the previous commit for details.
>
> # Other changes
>
> Rust 1.76.0 does not emit the `.debug_pub{names,types}` sections anymore
> for DWARFv4 [4][5]. For instance, in the uncompressed debug info case,
> this debug information took:
>
> samples/rust/rust_minimal.o ~64 KiB (~18% of total object size)
> rust/kernel.o ~92 KiB (~15%)
> rust/core.o ~114 KiB ( ~5%)
>
> In the compressed debug info (zlib) case:
>
> samples/rust/rust_minimal.o ~11 KiB (~6%)
> rust/kernel.o ~17 KiB (~5%)
> rust/core.o ~21 KiB (~1.5%)
>
> In addition, the `rustc_codegen_gcc` backend now does not emit the
> `.eh_frame` section when compiling under `-Cpanic=abort` [6], thus
> removing the need for the patch in the CI to compile the kernel [7].
> Moreover, it also now emits the `.comment` section too [6].
>
> # `alloc` upgrade and reviewing
[...]
> Link: https://github.com/rust-lang/rust/blob/stable/RELEASES.md#version-1760-2024-02-08 [1]
> Link: https://rust-for-linux.com/rust-version-policy [2]
> Link: https://github.com/Rust-for-Linux/linux/issues/2 [3]
> Link: https://github.com/rust-lang/compiler-team/issues/688 [4]
> Link: https://github.com/rust-lang/rust/pull/117962 [5]
> Link: https://github.com/rust-lang/rust/pull/118068 [6]
> Link: https://github.com/Rust-for-Linux/ci-rustc_codegen_gcc [7]
> Signed-off-by: Miguel Ojeda <ojeda@xxxxxxxxxx>
Reviewed-by: Alice Ryhl <aliceryhl@xxxxxxxxxx>
