[PATCH 00/13] Support several Rust toolchain versions

Miguel Ojeda
2024-07-01T18:36:47Z

Hi all,

It is time to start supporting several Rust toolchain versions and thus
establish a minimum Rust compiler and `bindgen` version.

For the Rust compiler, we will start with a window of two stable
releases, and widen it over time. This series keeps the minimum where
it is (1.78.0), but 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. A documentation adds the instructions for each of them.

In addition, Rust for Linux is now being built-tested in Rust's
pre-merge CI. 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.

Similarly, we kept the minimum as it is for `bindgen`. `bindgen` is also
adding the kernel to its CI -- thanks!

Cheers,
Miguel

Miguel Ojeda (13):
rust: macros: indent list item in `paste!`'s docs
rust: init: simplify from `map_err` to `inspect_err`
rust: allow `dead_code` for never constructed bindings
rust: relax most deny-level lints to warnings
rust: simplify Clippy warning flags set
rust: start supporting several compiler versions
rust: warn about `bindgen` versions 0.66.0 and 0.66.1
rust: work around `bindgen` 0.69.0 issue
rust: avoid assuming a particular `bindgen` build
rust: start supporting several `bindgen` versions
kbuild: rust: add `rustc-version` support
rust: support the new `-Zub-checks` flag
docs: rust: quick-start: add section on Linux distributions

Documentation/process/changes.rst | 9 +--
Documentation/rust/quick-start.rst | 118 +++++++++++++++++++++++------
Makefile | 29 +++----
init/Kconfig | 11 ++-
lib/Kconfig.debug | 18 +++++
rust/Makefile | 4 +-
rust/bindings/lib.rs | 1 +
rust/kernel/init.rs | 12 +--
rust/macros/lib.rs | 2 +-
rust/uapi/lib.rs | 1 +
scripts/Kconfig.include | 6 ++
scripts/Makefile.compiler | 4 +
scripts/rust_is_available.sh | 20 ++---
scripts/rust_is_available_test.py | 40 +++++-----
scripts/rustc-version.sh | 52 +++++++++++++
15 files changed, 238 insertions(+), 89 deletions(-)
create mode 100755 scripts/rustc-version.sh

base-commit: f2661062f16b2de5d7b6a5c42a9a5c96326b8454
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2.45.2