From: Tamir Duberstein Date: Sun, 15 Jun 2025 20:55:09 +0000 (-0400) Subject: rust: enable `clippy::cast_lossless` lint X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b7c8d7a8d251ab63fba3cc964f1928a216c28081;p=thirdparty%2Fkernel%2Flinux.git rust: enable `clippy::cast_lossless` lint Before Rust 1.29.0, Clippy introduced the `cast_lossless` lint [1]: > Rust’s `as` keyword will perform many kinds of conversions, including > silently lossy conversions. Conversion functions such as `i32::from` > will only perform lossless conversions. Using the conversion functions > prevents conversions from becoming silently lossy if the input types > ever change, and makes it clear for people reading the code that the > conversion is lossless. While this doesn't eliminate unchecked `as` conversions, it makes such conversions easier to scrutinize. It also has the slight benefit of removing a degree of freedom on which to bikeshed. Thus apply the changes and enable the lint -- no functional change intended. Link: https://rust-lang.github.io/rust-clippy/master/index.html#cast_lossless [1] Suggested-by: Benno Lossin Link: https://lore.kernel.org/all/D8ORTXSUTKGL.1KOJAGBM8F8TN@proton.me/ Reviewed-by: Benno Lossin Reviewed-by: Boqun Feng Signed-off-by: Tamir Duberstein Acked-by: FUJITA Tomonori Acked-by: Jocelyn Falempe Acked-by: Danilo Krummrich Link: https://lore.kernel.org/r/20250615-ptr-as-ptr-v12-5-f43b024581e8@gmail.com Signed-off-by: Miguel Ojeda --- diff --git a/Makefile b/Makefile index c66dd543b44e2..a95000adf2613 100644 --- a/Makefile +++ b/Makefile @@ -481,6 +481,7 @@ export rust_common_flags := --edition=2021 \ -Wclippy::all \ -Wclippy::as_ptr_cast_mut \ -Wclippy::as_underscore \ + -Wclippy::cast_lossless \ -Wclippy::ignored_unit_patterns \ -Wclippy::mut_mut \ -Wclippy::needless_bitwise_bool \ diff --git a/drivers/gpu/drm/drm_panic_qr.rs b/drivers/gpu/drm/drm_panic_qr.rs index dd55b1cb764d9..6b59d19ab6310 100644 --- a/drivers/gpu/drm/drm_panic_qr.rs +++ b/drivers/gpu/drm/drm_panic_qr.rs @@ -404,7 +404,7 @@ impl DecFifo { let mut out = 0; let mut exp = 1; for i in 0..poplen { - out += self.decimals[self.len + i] as u16 * exp; + out += u16::from(self.decimals[self.len + i]) * exp; exp *= 10; } Some((out, NUM_CHARS_BITS[poplen])) @@ -425,7 +425,7 @@ impl Iterator for SegmentIterator<'_> { match self.segment { Segment::Binary(data) => { if self.offset < data.len() { - let byte = data[self.offset] as u16; + let byte = u16::from(data[self.offset]); self.offset += 1; Some((byte, 8)) } else { diff --git a/drivers/gpu/nova-core/regs.rs b/drivers/gpu/nova-core/regs.rs index 5a12732303066..c1cb6d4c49ee6 100644 --- a/drivers/gpu/nova-core/regs.rs +++ b/drivers/gpu/nova-core/regs.rs @@ -32,7 +32,7 @@ impl NV_PMC_BOOT_0 { pub(crate) fn chipset(self) -> Result { self.architecture() .map(|arch| { - ((arch as u32) << Self::IMPLEMENTATION.len()) | self.implementation() as u32 + ((arch as u32) << Self::IMPLEMENTATION.len()) | u32::from(self.implementation()) }) .and_then(Chipset::try_from) } diff --git a/drivers/gpu/nova-core/regs/macros.rs b/drivers/gpu/nova-core/regs/macros.rs index 7ecc70efb3cd7..6851af8b58852 100644 --- a/drivers/gpu/nova-core/regs/macros.rs +++ b/drivers/gpu/nova-core/regs/macros.rs @@ -264,7 +264,7 @@ macro_rules! register { pub(crate) fn [](mut self, value: $to_type) -> Self { const MASK: u32 = $name::[<$field:upper _MASK>]; const SHIFT: u32 = $name::[<$field:upper _SHIFT>]; - let value = ((value as u32) << SHIFT) & MASK; + let value = (u32::from(value) << SHIFT) & MASK; self.0 = (self.0 & !MASK) | value; self diff --git a/rust/bindings/lib.rs b/rust/bindings/lib.rs index 81b6c7aa4916e..7631c9f6708d5 100644 --- a/rust/bindings/lib.rs +++ b/rust/bindings/lib.rs @@ -25,6 +25,7 @@ )] #[allow(dead_code)] +#[allow(clippy::cast_lossless)] #[allow(clippy::ptr_as_ptr)] #[allow(clippy::undocumented_unsafe_blocks)] #[cfg_attr(CONFIG_RUSTC_HAS_UNNECESSARY_TRANSMUTES, allow(unnecessary_transmutes))] diff --git a/rust/kernel/net/phy.rs b/rust/kernel/net/phy.rs index 32ea43ece6465..65ac4d59ad777 100644 --- a/rust/kernel/net/phy.rs +++ b/rust/kernel/net/phy.rs @@ -142,7 +142,7 @@ impl Device { // SAFETY: The struct invariant ensures that we may access // this field without additional synchronization. let bit_field = unsafe { &(*self.0.get())._bitfield_1 }; - bit_field.get(13, 1) == bindings::AUTONEG_ENABLE as u64 + bit_field.get(13, 1) == u64::from(bindings::AUTONEG_ENABLE) } /// Gets the current auto-negotiation state. @@ -427,7 +427,7 @@ impl Adapter { // where we hold `phy_device->lock`, so the accessors on // `Device` are okay to call. let dev = unsafe { Device::from_raw(phydev) }; - T::match_phy_device(dev) as i32 + T::match_phy_device(dev).into() } /// # Safety diff --git a/rust/uapi/lib.rs b/rust/uapi/lib.rs index e79a1f49f055f..08e68ebef6062 100644 --- a/rust/uapi/lib.rs +++ b/rust/uapi/lib.rs @@ -14,6 +14,7 @@ #![cfg_attr(test, allow(unsafe_op_in_unsafe_fn))] #![allow( clippy::all, + clippy::cast_lossless, clippy::ptr_as_ptr, clippy::undocumented_unsafe_blocks, dead_code,