[PATCH] kbuild: rust: support stabilized flag `-Cprofile-sample-use` for Rust >= 1.100

[Miguel Ojeda <ojeda@kernel.org>]

Starting with Rust 1.100.0 (expected 2026-11-12), the
`-Zprofile-sample-use` flag has been stabilized as
`-Cprofile-sample-use` and the former is not available anymore [1].

Without this change, when building with `CLANG_AUTOFDO_PROFILE` set, one
gets in the latest betas and nightlies:

    error: unknown unstable option: `profile-sample-use`

Thus pass the right name.

Cc: stable@vger.kernel.org # Needed in 7.3.y.
Link: https://github.com/rust-lang/rust/pull/155942 [1]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
I can take it via `rust-fixes` to get it in for the release, but please
let me know if you prefer to do something else. Thanks!

 scripts/Makefile.autofdo | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/scripts/Makefile.autofdo b/scripts/Makefile.autofdo
index 57a3aba6ffc2..32c18df237f1 100644
--- a/scripts/Makefile.autofdo
+++ b/scripts/Makefile.autofdo
@@ -13,7 +13,7 @@ endif
 ifdef CLANG_AUTOFDO_PROFILE
   CFLAGS_AUTOFDO_CLANG += -fprofile-sample-use=$(CLANG_AUTOFDO_PROFILE) -ffunction-sections
   CFLAGS_AUTOFDO_CLANG += -fsplit-machine-functions
-  RUSTFLAGS_AUTOFDO_CLANG += -Zprofile-sample-use=$(CLANG_AUTOFDO_PROFILE) -Zfunction-sections=y
+  RUSTFLAGS_AUTOFDO_CLANG += $(if $(call rustc-min-version,110000),-Cprofile-sample-use,-Zprofile-sample-use)=$(CLANG_AUTOFDO_PROFILE) -Zfunction-sections=y
   RUSTFLAGS_AUTOFDO_CLANG += -Cllvm-args=-split-machine-functions
 endif


base-commit: 57d916a3eb765ee0577d269bb2ac1bdf3a7a7f40
--
2.56.0