It is time to start supporting several Rust compiler versions and thus
establish a minimum Rust version.
We may still want to upgrade the minimum sometimes in the beginning since
there may be important features coming into the language that improve
how we write code (e.g. field projections), which may or may not make
sense to support conditionally.
We will start with a window of two stable releases, and widen it over
time. Thus this patch does not move the current minimum (1.78.0), but
instead adds support for the recently released 1.79.0.
This should already be enough for kernel developers in distributions that
provide recent Rust compiler versions routinely, such as Arch Linux,
Debian Unstable (outside the freeze period), Fedora Linux, Gentoo
Linux (especially the testing channel), Nix (unstable) and openSUSE
Tumbleweed. See the documentation patch about it later in this series.
In addition, Rust for Linux is now being built-tested in Rust's pre-merge
CI [1]. That is, every change that is attempting to land into the Rust
compiler is tested against the kernel, and it is merged only if it passes
-- thanks to the Rust project for that!
Thus, with the pre-merge CI in place, both projects hope to avoid
unintentional changes to Rust that break the kernel. This means that,
in general, apart from intentional changes on their side (that we will
need to workaround conditionally on our side), the upcoming Rust compiler
versions should generally work.
For instance, currently, the beta (1.80.0) and nightly (1.81.0) branches
work as well.
Of course, the Rust for Linux CI job in the Rust toolchain may still need
to be temporarily disabled for different reasons, but the intention is
to help bring Rust for Linux into stable Rust.
Link: https://github.com/rust-lang/rust/pull/125209 [1]
Reviewed-by: Finn Behrens <me@kloenk.dev>
Tested-by: Benno Lossin <benno.lossin@proton.me>
Tested-by: Andreas Hindborg <a.hindborg@samsung.com>
Link: https://lore.kernel.org/r/20240709160615.998336-7-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
The `rust_is_available.sh` script runs for everybody compiling the
kernel, even if not using Rust. Therefore, it is important to ensure
that the script is correct to avoid breaking people's compilation.
In addition, the script needs to be able to handle a set of subtle
cases, including parsing version strings of different tools.
Therefore, maintenance of this script can be greatly eased with
a set of tests.
Thus add a test suite to cover hopefully most of the setups that
the script may encounter in the wild. Extra setups can be easily
added later on if missing.
The script currently covers all the branches of the shell script,
including several ways in which they may be entered.
Python is used for this script, since the script under test
does not depend on Rust, thus hopefully making it easier for others
to use if the need arises.
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Link: https://lore.kernel.org/r/20230616001631.463536-12-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
