Re: [OE-core] [PATCH v2 03/15] rust: install Rust library sources for 'make rustavailable' support

[Richard Purdie <richard.purdie@linuxfoundation.org>]

On Tue, 2025-12-30 at 06:15 -0800, Sadineni, Harish via lists.openembedded.org wrote:
> From: Harish Sadineni <Harish.Sadineni@windriver.com>
> 
> The `make rustavailable` process (1) expects the Rust standard library source files (e.g., `lib.rs`)
> to be present in the `library/` directory under `rustlib/src/rust/`.
> 
> This patch ensures the required sources are available by:
> - Copying the `library/` directory from the Rust source tree into `${TMPDIR}/work-shared/rust`
>   during the snapshot setup.
> - Installing the `library/` directory into `${SDKPATHNATIVE}/usr/lib/rustlib/src/rust` for the
>   `nativesdk` class, making them available in them available in sdk
> 
> 1) See the kernel tree for Documentation/rust/quick-start.rst in the section: Requirements: Building
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/rust/quick-start.rst#n145
> 
> Signed-off-by: Harish Sadineni <Harish.Sadineni@windriver.com>
> ---
>  meta/recipes-devtools/rust/rust_1.91.1.bb | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
> 
> diff --git a/meta/recipes-devtools/rust/rust_1.91.1.bb b/meta/recipes-devtools/rust/rust_1.91.1.bb
> index a25f65f674..7644ecf2d2 100644
> --- a/meta/recipes-devtools/rust/rust_1.91.1.bb
> +++ b/meta/recipes-devtools/rust/rust_1.91.1.bb
> @@ -63,6 +63,16 @@ do_rust_setup_snapshot () {
>          done
>      fi
>  }
> +
> +do_rust_setup_snapshot:append:class-native () {
> +   if ${@bb.utils.contains('DISTRO_FEATURES', 'rust-kernel', 'true', 'false', d)}; then
> +         if [ ! -d "${TMPDIR}/work-shared/rust" ]; then
> +                mkdir -p ${TMPDIR}/work-shared/rust
> +                cp -r ${RUSTSRC}/library ${TMPDIR}/work-shared/rust/.
> +         fi
> +   fi
> +}
> +
>  addtask rust_setup_snapshot after do_unpack before do_configure
>  addtask do_test_compile after do_configure do_rust_gen_targets
>  do_rust_setup_snapshot[dirs] += "${WORKDIR}/rust-snapshot"
> @@ -314,6 +324,13 @@ rust_do_install:class-nativesdk() {
>  	export CARGO_TARGET_${RUST_HOST_TRIPLE}_RUNNER="\$OECORE_NATIVE_SYSROOT/lib/${SDKLOADER}"
>  	export CC_$RUST_HOST_CC="${CCACHE}${HOST_PREFIX}gcc"
>  	EOF
> +    
> +    if ${@bb.utils.contains('DISTRO_FEATURES', 'rust-kernel', 'true', 'false', d)}; then
> +           if [ ! -d ${D}${SDKPATHNATIVE}/usr/lib/rustlib/src/rust ]; then
> +                mkdir -p ${D}${SDKPATHNATIVE}/usr/lib/rustlib/src/rust
> +                cp -r --no-preserve=ownership  ${S}/library ${D}${SDKPATHNATIVE}/usr/lib/rustlib/src/rust/
> +           fi
> +    fi
>  }
>  
>  FILES:${PN} += "${base_prefix}/environment-setup.d"

The commit message should mention the size of these files. Does this
make sense as a distro feature or should we just do this all the time?
Do the nativesdk components get packaged separately? If they were, we
could then make that an SDK feature instead. What happens for on target
kernel module development? Shouldn't there be a target package too?

Cheers,

Richard