[PATCH 02/13] rust: init: simplify from `map_err` to `inspect_err`

Miguel Ojeda
2024-07-01T18:36:55Z

A new complexity lint, `manual_inspect` [1], has been introduced in
the upcoming Rust 1.81 (currently in nightly), which checks for uses of
`map*` which return the original item:

error:
--> rust/kernel/init.rs:846:23
|
846 | (self.1)(val).map_err(|e| {
| ^^^^^^^
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#manual_inspect
= note: `-D clippy::manual-inspect` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(clippy::manual_inspect)]`
help: try
|
846 ~ (self.1)(val).inspect_err(|e| {
847 | // SAFETY: `slot` was initialized above.
848 ~ unsafe { core::ptr::drop_in_place(slot) };
|

Thus clean them up.

Link: https://rust-lang.github.io/rust-clippy/master/index.html#/manual_inspect [1]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
---
rust/kernel/init.rs | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/rust/kernel/init.rs b/rust/kernel/init.rs
index 68605b633e73..07bacf134c19 100644
--- a/rust/kernel/init.rs
+++ b/rust/kernel/init.rs
@@ -843,11 +843,9 @@ unsafe fn __pinned_init(self, slot: *mut T) -> Result<(), E> {
let val = unsafe { &mut *slot };
// SAFETY: `slot` is considered pinned.
let val = unsafe { Pin::new_unchecked(val) };
- (self.1)(val).map_err(|e| {
+ (self.1)(val).inspect_err(|_|
// SAFETY: `slot` was initialized above.
- unsafe { core::ptr::drop_in_place(slot) };
- e
- })
+ unsafe { core::ptr::drop_in_place(slot) })
}
}

@@ -941,11 +939,9 @@ unsafe fn __init(self, slot: *mut T) -> Result<(), E> {
// SAFETY: All requirements fulfilled since this function is `__init`.
unsafe { self.0.__pinned_init(slot)? };
// SAFETY: The above call initialized `slot` and we still have unique access.
- (self.1)(unsafe { &mut *slot }).map_err(|e| {
+ (self.1)(unsafe { &mut *slot }).inspect_err(|_|
// SAFETY: `slot` was initialized above.
- unsafe { core::ptr::drop_in_place(slot) };
- e
- })
+ unsafe { core::ptr::drop_in_place(slot) })
}
}

--
2.45.2