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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-09-05 11:59:05 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-09-05 11:59:05 -0700 |
| commit | 9f0346dcbea363787186c94ef94dd01aaa215afa (patch) | |
| tree | b81c168f4d0dbe4c7f4750f4598d48a6deb72094 /rust/syn/drops.rs | |
| download | linux-stable-9f0346dcbea363787186c94ef94dd01aaa215afa.tar.gz linux-stable-9f0346dcbea363787186c94ef94dd01aaa215afa.zip | |
Merge tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-coregrafted
Pull driver core fixes from Danilo Krummrich:
- Fix kernfs listxattr() not returning security xattr names (e.g.
SELinux labels) when the kernfs node has no allocated kernfs_iattrs
- Fix silent truncation of IRQ vector indices in the Rust PCI
abstractions
- Don't select OF from DRIVER_PE_KUNIT_TEST; skip the test when OF is
disabled instead of silently enabling extra kernel functionality
- Russ Weight is retiring from kernel development; update the Firmware
Loader sysfs contact to the driver-core mailing list, add a CREDITS
entry for Firmware Upload, and update MAINTAINERS accordingly
* tag 'driver-core-7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core:
MAINTAINERS: Remove Russ Weight from Firmware Loader
CREDITS: Add CREDITS entry for Firmware Upload
firmware_loader: Change contact for sysfs nodes
rust: pci: reject IRQ vector indices that do not fit in u32
kernfs: preserve security xattrs without allocating iattrs
drivers: base: test: DRIVER_PE_KUNIT_TEST should not select OF
Diffstat (limited to 'rust/syn/drops.rs')
| -rw-r--r-- | rust/syn/drops.rs | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/rust/syn/drops.rs b/rust/syn/drops.rs new file mode 100644 index 000000000..2c4ae333d --- /dev/null +++ b/rust/syn/drops.rs @@ -0,0 +1,60 @@ +// SPDX-License-Identifier: Apache-2.0 OR MIT + +use std::iter; +use std::mem::ManuallyDrop; +use std::ops::{Deref, DerefMut}; +use std::option; +use std::slice; + +#[repr(transparent)] +pub(crate) struct NoDrop<T: ?Sized>(ManuallyDrop<T>); + +impl<T> NoDrop<T> { + pub(crate) fn new(value: T) -> Self + where + T: TrivialDrop, + { + NoDrop(ManuallyDrop::new(value)) + } +} + +impl<T: ?Sized> Deref for NoDrop<T> { + type Target = T; + fn deref(&self) -> &Self::Target { + &self.0 + } +} + +impl<T: ?Sized> DerefMut for NoDrop<T> { + fn deref_mut(&mut self) -> &mut Self::Target { + &mut self.0 + } +} + +pub(crate) trait TrivialDrop {} + +impl<T> TrivialDrop for iter::Empty<T> {} +impl<T> TrivialDrop for slice::Iter<'_, T> {} +impl<T> TrivialDrop for slice::IterMut<'_, T> {} +impl<T> TrivialDrop for option::IntoIter<&T> {} +impl<T> TrivialDrop for option::IntoIter<&mut T> {} + +#[test] +fn test_needs_drop() { + use std::mem::needs_drop; + + struct NeedsDrop; + + impl Drop for NeedsDrop { + fn drop(&mut self) {} + } + + assert!(needs_drop::<NeedsDrop>()); + + // Test each of the types with a handwritten TrivialDrop impl above. + assert!(!needs_drop::<iter::Empty<NeedsDrop>>()); + assert!(!needs_drop::<slice::Iter<NeedsDrop>>()); + assert!(!needs_drop::<slice::IterMut<NeedsDrop>>()); + assert!(!needs_drop::<option::IntoIter<&NeedsDrop>>()); + assert!(!needs_drop::<option::IntoIter<&mut NeedsDrop>>()); +} |
