objtool/rust: add one more noreturn Rust function for Rust 1.87.0

Starting with Rust 1.87.0 (expected 2025-05-15), `objtool` may report: rust/core.o: warning: objtool: _R..._4core9panicking9panic_fmt() falls through to next function _R..._4core9panicking18panic_nounwind_fmt() rust/core.o: warning: objtool: _R..._4core9panicking18panic_nounwind_fmt() falls through to next function _R..._4core9panicking5panic() The reason is that `rust_begin_unwind` is now mangled: _R..._7___rustc17rust_begin_unwind Thus add the mangled one to the list so that `objtool` knows it is actually `noreturn`. See commit 56d680d ("objtool/rust: list `noreturn` Rust functions") for more details. Alternatively, we could remove the fixed one in `noreturn.h` and relax this test to cover both, but it seems best to be strict as long as we can. Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs). Cc: Josh Poimboeuf <jpoimboe@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20250502140237.1659624-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Author: ojeda

tools/objtool/check.c

@@ -227,6 +227,7 @@ static bool is_rust_noreturn(const struct symbol *func)
  str_ends_with(func->name, "_4core9panicking19assert_failed_inner")||
  str_ends_with(func->name, "_4core9panicking30panic_null_pointer_dereference")||
  str_ends_with(func->name, "_4core9panicking36panic_misaligned_pointer_dereference")||
+ str_ends_with(func->name, "_7___rustc17rust_begin_unwind")||
  strstr(func->name, "_4core9panicking13assert_failed")||
  strstr(func->name, "_4core9panicking11panic_const24panic_const_")||
  (strstr(func->name, "_4core5slice5index24slice_") &&