[PATCH] objtool/rust: add one more `noreturn` Rust function

[Miguel Ojeda <ojeda@kernel.org>]

When the pointer formatting series [1] is applied and KUnit tests
are enabled, `objtool` would report an error with any of our
supported Rust versions. For instance, with Rust 1.97.1:

    rust/kernel.o: error: objtool: _R..._4core3fmt7Pointer3fmtB7_()
    falls through to next function _R..._4core7convert5AsRefNtB5_4BStrE6as_ref()

Or, with Rust 1.85.0:

    rust/kernel.o: error: objtool: _R..._4core3fmt7Pointer3fmtB7_()
    falls through to next function _R..._4core3ffi5c_str4CStrENtNtBS_3fmt7Display3fmtB7_()

This happens due to calls to the `noreturn` symbol:

    core::str::slice_error_fail

Thus add the mangled one to the list so that `objtool` knows it is
actually `noreturn`.

See commit 56d680dd23c3 ("objtool/rust: list `noreturn` Rust functions")
for more details.

Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Reported-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/rust-for-linux/anLxXvCKBcAVf91_@google.com/
Link: https://lore.kernel.org/rust-for-linux/20260706-hashedptr-v13-0-377a07f2f78d@kylinos.cn/ [1]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
 tools/objtool/check.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 87db9f4ed9e2..3ab5b9f1c6a4 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -195,6 +195,7 @@ static bool is_rust_noreturn(const struct symbol *func)
 	return str_ends_with(func->name, "_4core3num20from_str_radix_panic")				||
 	       str_ends_with(func->name, "_4core3num22from_ascii_radix_panic")				||
 	       str_ends_with(func->name, "_4core3num28from_ascii_bytes_radix_panic")			||
+	       str_ends_with(func->name, "_4core3str16slice_error_fail")				||
 	       str_ends_with(func->name, "_4core5sliceSp15copy_from_slice17len_mismatch_fail")		||
 	       str_ends_with(func->name, "_4core6option13expect_failed")				||
 	       str_ends_with(func->name, "_4core6option13unwrap_failed")				||

base-commit: dc01dfb37b34beeefcfe1c3055364d41a4070c7e
-- 
2.55.0