rust: kbuild: disambiguate zerocopy_derive for rusttest

The `rustc-dev` components for Rust 1.82.0 through 1.87.0 include a
precompiled `zerocopy_derive` procedural macro in the sysroot. This
range includes Rust 1.85.0, our minimum supported version.

This makes `rusttest` fail because the compiler finds both the sysroot
copy and the copy built in `rust/test`:

    error[E0464]: multiple candidates for `dylib` dependency `zerocopy_derive` found
      --> rust/kernel/prelude.rs:70:9
       |
    70 | pub use zerocopy_derive::{
       |         ^^^^^^^^^^^^^^^
       |
       = note: candidate #1: .../lib/rustlib/x86_64-unknown-linux-gnu/lib/libzerocopy_derive-54d2b38896fa6bc5.so
       = note: candidate #2: .../rust/test/libzerocopy_derive.so

Commit fe39a233ea ("rust: kbuild: disambiguate `zerocopy` for
`rusttest`") fixed the equivalent ambiguity for `zerocopy`.

Thus point to the dependency explicitly in this case too.

Cc: Antoni Boucher <bouanto@zoho.com>
Cc: stable@vger.kernel.org
Fixes: 5060549804 ("rust: zerocopy-derive: enable support in kbuild")
Link: https://patch.msgid.link/20260823193529.156066-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This commit is contained in:
Miguel Ojeda 2026-08-23 21:35:29 +02:00
parent 7dd6343fc1
commit 1b0bab4a87

View File

@ -350,7 +350,8 @@ rusttestlib-pin_init: $(src)/pin-init/src/lib.rs rusttestlib-macros \
rusttestlib-kernel: private rustc_target_flags = --extern ffi \
--extern build_error --extern macros --extern pin_init \
--extern bindings --extern uapi \
--extern zerocopy=$(objtree)/$(obj)/test/libzerocopy.rlib --extern zerocopy_derive
--extern zerocopy=$(objtree)/$(obj)/test/libzerocopy.rlib \
--extern zerocopy_derive=$(objtree)/$(obj)/test/$(libzerocopy_derive_name)
rusttestlib-kernel: $(src)/kernel/lib.rs rusttestlib-bindings rusttestlib-uapi \
rusttestlib-build_error rusttestlib-pin_init $(obj)/$(libmacros_name) \
$(obj)/bindings.o rusttestlib-zerocopy rusttestlib-zerocopy_derive FORCE