On Fri Mar 7, 2025 at 5:58 PM CET, Benno Lossin wrote: > On Fri Mar 7, 2025 at 5:41 PM CET, Tamir Duberstein wrote: >> In Rust 1.51.0, Clippy introduced the `ignored_unit_patterns` lint [1]: > > You link to the `ptr_as_ptr` lint though, is this a typo? > >>> Though `as` casts between raw pointers are not terrible, >>> `pointer::cast` is safer because it cannot accidentally change the >>> pointer's mutability, nor cast the pointer to other types like `usize`. >> >> There are a few classes of changes required: >> - Modules generated by bindgen are marked >> `#[allow(clippy::ptr_as_ptr)]`. >> - Inferred casts (` as _`) are replaced with `.cast()`. >> - Ascribed casts (` as *... T`) are replaced with `.cast::<T>()`. >> - Multistep casts from references (` as *const _ as *const T`) are >> replaced with `let x: *const _ = &x;` and `.cast()` or `.cast::<T>()` >> according to the previous rules. The intermediate `let` binding is >> required because `(x as *const _).cast::<T>()` results in inference >> failure. >> - Native literal C strings are replaced with `c_str!().as_char_ptr()`. > > These all seem very nice, thanks! I think it would also be a good idea > to enable `ptr_cast_constness` [1], since those are the other kind of > `as` usage that we should be doing via `cast_mut`/`cast_const`. I didn't mean to make this sound like you *have* to do the work. If you find the time and want to do it, then great, otherwise we can turn this into a good-first-issue :) --- Cheers, Benno > There are still some legitimate uses of `as` casts, when unsizing > values. I don't know if these two lints can trigger on those, it would > be nice if they don't. So those should continue to use `as`, but other > than that, there shouldn't be any `as` in our code :) > > [1]: https://rust-lang.github.io/rust-clippy/master/index.html#ptr_cast_constness > > (I will take a look at the patch itself a bit later) > > --- > Cheers, > Benno > >> Apply these changes and enable the lint -- no functional change >> intended. >> >> Link: https://rust-lang.github.io/rust-clippy/master/index.html#ptr_as_ptr [1] >> Signed-off-by: Tamir Duberstein <tamird@xxxxxxxxx> >> --- >> Makefile | 1 + >> rust/bindings/lib.rs | 1 + >> rust/kernel/alloc/allocator_test.rs | 2 +- >> rust/kernel/alloc/kvec.rs | 4 ++-- >> rust/kernel/device.rs | 5 +++-- >> rust/kernel/devres.rs | 2 +- >> rust/kernel/error.rs | 2 +- >> rust/kernel/fs/file.rs | 2 +- >> rust/kernel/kunit.rs | 15 +++++++-------- >> rust/kernel/lib.rs | 4 ++-- >> rust/kernel/list/impl_list_item_mod.rs | 2 +- >> rust/kernel/pci.rs | 2 +- >> rust/kernel/platform.rs | 4 +++- >> rust/kernel/print.rs | 11 +++++------ >> rust/kernel/seq_file.rs | 3 ++- >> rust/kernel/str.rs | 2 +- >> rust/kernel/sync/poll.rs | 2 +- >> rust/kernel/workqueue.rs | 10 +++++----- >> rust/uapi/lib.rs | 1 + >> 19 files changed, 40 insertions(+), 35 deletions(-)
