Starting with Rust 1.87.0 (expected 2025-05-15) [1], Clippy may expand the `ptr_eq` lint, e.g.:
error: use `core::ptr::eq` when comparing raw pointers --> rust/kernel/list.rs:438:12 | 438 | if self.first == item { | ^^^^^^^^^^^^^^^^^^ help: try: `core::ptr::eq(self.first, item)` | = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ptr_eq = note: `-D clippy::ptr-eq` implied by `-D warnings` = help: to override `-D warnings` add `#[allow(clippy::ptr_eq)]`
Thus clean the few cases we have.
This patch may not be actually needed by the time Rust 1.87.0 releases since a PR to relax the lint has been beta nominated [2] due to reports of being too eager (at least by default) [3].
Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs). Link: https://github.com/rust-lang/rust-clippy/pull/14339 [1] Link: https://github.com/rust-lang/rust-clippy/pull/14526 [2] Link: https://github.com/rust-lang/rust-clippy/issues/14525 [3] Signed-off-by: Miguel Ojeda ojeda@kernel.org --- rust/kernel/alloc/kvec.rs | 2 +- rust/kernel/list.rs | 12 ++++++------ 2 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/rust/kernel/alloc/kvec.rs b/rust/kernel/alloc/kvec.rs index ae9d072741ce..cde911551327 100644 --- a/rust/kernel/alloc/kvec.rs +++ b/rust/kernel/alloc/kvec.rs @@ -743,7 +743,7 @@ fn into_raw_parts(self) -> (*mut T, NonNull<T>, usize, usize) { pub fn collect(self, flags: Flags) -> Vec<T, A> { let old_layout = self.layout; let (mut ptr, buf, len, mut cap) = self.into_raw_parts(); - let has_advanced = ptr != buf.as_ptr(); + let has_advanced = !core::ptr::eq(ptr, buf.as_ptr());
if has_advanced { // Copy the contents we have advanced to at the beginning of the buffer. diff --git a/rust/kernel/list.rs b/rust/kernel/list.rs index a335c3b1ff5e..c63cbeee3316 100644 --- a/rust/kernel/list.rs +++ b/rust/kernel/list.rs @@ -435,7 +435,7 @@ unsafe fn remove_internal_inner( // * If `item` was the only item in the list, then `prev == item`, and we just set // `item->next` to null, so this correctly sets `first` to null now that the list is // empty. - if self.first == item { + if core::ptr::eq(self.first, item) { // SAFETY: The `prev` pointer is the value that `item->prev` had when it was in this // list, so it must be valid. There is no race since `prev` is still in the list and we // still have exclusive access to the list. @@ -556,7 +556,7 @@ fn next(&mut self) -> Option<ArcBorrow<'a, T>> { let next = unsafe { (*current).next }; // INVARIANT: If `current` was the last element of the list, then this updates it to null. // Otherwise, we update it to the next element. - self.current = if next != self.stop { + self.current = if !core::ptr::eq(next, self.stop) { next } else { ptr::null_mut() @@ -726,7 +726,7 @@ impl<'a, T: ?Sized + ListItem<ID>, const ID: u64> Cursor<'a, T, ID> { fn prev_ptr(&self) -> *mut ListLinksFields { let mut next = self.next; let first = self.list.first; - if next == first { + if core::ptr::eq(next, first) { // We are before the first element. return core::ptr::null_mut(); } @@ -788,7 +788,7 @@ pub fn move_next(&mut self) -> bool { // access the `next` field. let mut next = unsafe { (*self.next).next };
- if next == self.list.first { + if core::ptr::eq(next, self.list.first) { next = core::ptr::null_mut(); }
@@ -802,7 +802,7 @@ pub fn move_next(&mut self) -> bool { /// If the cursor is before the first element, then this call does nothing. This call returns /// `true` if the cursor's position was changed. pub fn move_prev(&mut self) -> bool { - if self.next == self.list.first { + if core::ptr::eq(self.next, self.list.first) { return false; }
@@ -822,7 +822,7 @@ fn insert_inner(&mut self, item: ListArc<T, ID>) -> *mut ListLinksFields { // * `ptr` is an element in the list or null. // * if `ptr` is null, then `self.list.first` is null so the list is empty. let item = unsafe { self.list.insert_inner(item, ptr) }; - if self.next == self.list.first { + if core::ptr::eq(self.next, self.list.first) { // INVARIANT: We just inserted `item`, so it's a member of list. self.list.first = item; }