rust: configure clippy to only report issues relevant to our MSRV

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/38807>

.gitlab-ci/container/build-rust.sh

@@ -15,7 +15,8 @@ section_start rust "Building Rust toolchain"
 # This version number should match what we require in meson.build so we catch
 # build issues from patches relying on new features in newer Rust versions.
 # Keep this is sync with the `rustc.version()` check in meson.build, and with
-# the `rustup default` line in .gitlab-ci/meson/build.sh
+# the `rustup default` line in .gitlab-ci/meson/build.sh and the `msrv` in
+# clippy.toml
 MINIMUM_SUPPORTED_RUST_VERSION=1.82.0
 
 # This version number can be bumped freely, to benefit from the latest

.gitlab-ci/meson/build.sh

@@ -44,7 +44,8 @@ fi
 # Android manages the rust toolchain differently, ignore that case
 if [ "$CI_JOB_STAGE" = "build-for-tests" ] && [[ "$CI_JOB_NAME" != *android* ]]; then
   # Keep this in sync with the `rustc.version()` check in meson.build, and
-  # MINIMUM_SUPPORTED_RUST_VERSION in .gitlab-ci/container/build-rust.sh
+  # MINIMUM_SUPPORTED_RUST_VERSION in .gitlab-ci/container/build-rust.sh and the
+  # `msrv` in clippy.toml
   rustup default 1.82.0
 fi
 

clippy.toml

@@ -0,0 +1,4 @@
+# Keep this in sync with the `rustc.version()` check in meson.build, the
+# MINIMUM_SUPPORTED_RUST_VERSION in .gitlab-ci/container/build-rust.sh, the
+# `rustup default` line in .gitlab-ci/meson/build.sh
+msrv = "1.82.0"

meson.build

@@ -790,7 +790,7 @@ if with_gallium_rusticl or with_nouveau_vk or with_tools.contains('etnaviv') or
 
   # Keep this in sync with the MINIMUM_SUPPORTED_RUST_VERSION in
   # .gitlab-ci/container/build-rust.sh and the `rustup default` line in
-  # .gitlab-ci/meson/build.sh
+  # .gitlab-ci/meson/build.sh and the `msrv` in clippy.toml
   if rustc.version().version_compare('< 1.82')
     error('Mesa requires Rust 1.82.0 or newer')
   endif