diff options
Diffstat (limited to 'rust')
| -rw-r--r-- | rust/alloc/alloc.rs | 32 | ||||
| -rw-r--r-- | rust/alloc/lib.rs | 6 | ||||
| -rw-r--r-- | rust/alloc/slice.rs | 2 | ||||
| -rw-r--r-- | rust/alloc/vec/mod.rs | 87 |
4 files changed, 112 insertions, 15 deletions
diff --git a/rust/alloc/alloc.rs b/rust/alloc/alloc.rs index 8cb4a31cf6e5..150e13750ff7 100644 --- a/rust/alloc/alloc.rs +++ b/rust/alloc/alloc.rs @@ -345,18 +345,31 @@ extern "Rust" { fn __rust_alloc_error_handler(size: usize, align: usize) -> !; } -/// Abort on memory allocation error or failure. +/// Signal a memory allocation error. /// -/// Callers of memory allocation APIs wishing to abort computation +/// Callers of memory allocation APIs wishing to cease execution /// in response to an allocation error are encouraged to call this function, -/// rather than directly invoking `panic!` or similar. +/// rather than directly invoking [`panic!`] or similar. /// -/// The default behavior of this function is to print a message to standard error -/// and abort the process. -/// It can be replaced with [`set_alloc_error_hook`] and [`take_alloc_error_hook`]. +/// This function is guaranteed to diverge (not return normally with a value), but depending on +/// global configuration, it may either panic (resulting in unwinding or aborting as per +/// configuration for all panics), or abort the process (with no unwinding). +/// +/// The default behavior is: +/// +/// * If the binary links against `std` (typically the case), then +/// print a message to standard error and abort the process. +/// This behavior can be replaced with [`set_alloc_error_hook`] and [`take_alloc_error_hook`]. +/// Future versions of Rust may panic by default instead. +/// +/// * If the binary does not link against `std` (all of its crates are marked +/// [`#![no_std]`][no_std]), then call [`panic!`] with a message. +/// [The panic handler] applies as to any panic. /// /// [`set_alloc_error_hook`]: ../../std/alloc/fn.set_alloc_error_hook.html /// [`take_alloc_error_hook`]: ../../std/alloc/fn.take_alloc_error_hook.html +/// [The panic handler]: https://doc.rust-lang.org/reference/runtime.html#the-panic_handler-attribute +/// [no_std]: https://doc.rust-lang.org/reference/names/preludes.html#the-no_std-attribute #[stable(feature = "global_alloc", since = "1.28.0")] #[rustc_const_unstable(feature = "const_alloc_error", issue = "92523")] #[cfg(all(not(no_global_oom_handling), not(test)))] @@ -397,9 +410,10 @@ pub mod __alloc_error_handler { if unsafe { __rust_alloc_error_handler_should_panic != 0 } { panic!("memory allocation of {size} bytes failed") } else { - core::panicking::panic_nounwind_fmt(format_args!( - "memory allocation of {size} bytes failed" - )) + core::panicking::panic_nounwind_fmt( + format_args!("memory allocation of {size} bytes failed"), + /* force_no_backtrace */ false, + ) } } } diff --git a/rust/alloc/lib.rs b/rust/alloc/lib.rs index 73b9ffd845d9..9c7ea73da108 100644 --- a/rust/alloc/lib.rs +++ b/rust/alloc/lib.rs @@ -90,8 +90,8 @@ #![warn(missing_docs)] #![allow(explicit_outlives_requirements)] #![warn(multiple_supertrait_upcastable)] -#![cfg_attr(not(bootstrap), allow(internal_features))] -#![cfg_attr(not(bootstrap), allow(rustdoc::redundant_explicit_links))] +#![allow(internal_features)] +#![allow(rustdoc::redundant_explicit_links)] // // Library features: // tidy-alphabetical-start @@ -122,6 +122,7 @@ #![feature(const_waker)] #![feature(core_intrinsics)] #![feature(core_panic)] +#![feature(deprecated_suggestion)] #![feature(dispatch_from_dyn)] #![feature(error_generic_member_access)] #![feature(error_in_core)] @@ -145,7 +146,6 @@ #![feature(ptr_metadata)] #![feature(ptr_sub_ptr)] #![feature(receiver_trait)] -#![feature(saturating_int_impl)] #![feature(set_ptr_value)] #![feature(sized_type_properties)] #![feature(slice_from_ptr_range)] diff --git a/rust/alloc/slice.rs b/rust/alloc/slice.rs index 6ac463bd3edc..1181836da5f4 100644 --- a/rust/alloc/slice.rs +++ b/rust/alloc/slice.rs @@ -594,7 +594,7 @@ impl<T> [T] { /// ``` #[rustc_allow_incoherent_impl] #[stable(feature = "rust1", since = "1.0.0")] - #[deprecated(since = "1.3.0", note = "renamed to join")] + #[deprecated(since = "1.3.0", note = "renamed to join", suggestion = "join")] pub fn connect<Separator>(&self, sep: Separator) -> <Self as Join<Separator>>::Output where Self: Join<Separator>, diff --git a/rust/alloc/vec/mod.rs b/rust/alloc/vec/mod.rs index 209a88cfe598..41ca71805ef0 100644 --- a/rust/alloc/vec/mod.rs +++ b/rust/alloc/vec/mod.rs @@ -1228,8 +1228,8 @@ impl<T, A: Allocator> Vec<T, A> { /// Shortens the vector, keeping the first `len` elements and dropping /// the rest. /// - /// If `len` is greater than the vector's current length, this has no - /// effect. + /// If `len` is greater or equal to the vector's current length, this has + /// no effect. /// /// The [`drain`] method can emulate `truncate`, but causes the excess /// elements to be returned instead of dropped. @@ -1336,6 +1336,15 @@ impl<T, A: Allocator> Vec<T, A> { /// is never written to (except inside an `UnsafeCell`) using this pointer or any pointer /// derived from it. If you need to mutate the contents of the slice, use [`as_mut_ptr`]. /// + /// This method guarantees that for the purpose of the aliasing model, this method + /// does not materialize a reference to the underlying slice, and thus the returned pointer + /// will remain valid when mixed with other calls to [`as_ptr`] and [`as_mut_ptr`]. + /// Note that calling other methods that materialize mutable references to the slice, + /// or mutable references to specific elements you are planning on accessing through this pointer, + /// as well as writing to those elements, may still invalidate this pointer. + /// See the second example below for how this guarantee can be used. + /// + /// /// # Examples /// /// ``` @@ -1349,8 +1358,25 @@ impl<T, A: Allocator> Vec<T, A> { /// } /// ``` /// + /// Due to the aliasing guarantee, the following code is legal: + /// + /// ```rust + /// unsafe { + /// let mut v = vec![0, 1, 2]; + /// let ptr1 = v.as_ptr(); + /// let _ = ptr1.read(); + /// let ptr2 = v.as_mut_ptr().offset(2); + /// ptr2.write(2); + /// // Notably, the write to `ptr2` did *not* invalidate `ptr1` + /// // because it mutated a different element: + /// let _ = ptr1.read(); + /// } + /// ``` + /// /// [`as_mut_ptr`]: Vec::as_mut_ptr + /// [`as_ptr`]: Vec::as_ptr #[stable(feature = "vec_as_ptr", since = "1.37.0")] + #[cfg_attr(not(bootstrap), rustc_never_returns_null_ptr)] #[inline] pub fn as_ptr(&self) -> *const T { // We shadow the slice method of the same name to avoid going through @@ -1366,6 +1392,15 @@ impl<T, A: Allocator> Vec<T, A> { /// Modifying the vector may cause its buffer to be reallocated, /// which would also make any pointers to it invalid. /// + /// This method guarantees that for the purpose of the aliasing model, this method + /// does not materialize a reference to the underlying slice, and thus the returned pointer + /// will remain valid when mixed with other calls to [`as_ptr`] and [`as_mut_ptr`]. + /// Note that calling other methods that materialize references to the slice, + /// or references to specific elements you are planning on accessing through this pointer, + /// may still invalidate this pointer. + /// See the second example below for how this guarantee can be used. + /// + /// /// # Examples /// /// ``` @@ -1383,7 +1418,25 @@ impl<T, A: Allocator> Vec<T, A> { /// } /// assert_eq!(&*x, &[0, 1, 2, 3]); /// ``` + /// + /// Due to the aliasing guarantee, the following code is legal: + /// + /// ```rust + /// unsafe { + /// let mut v = vec![0]; + /// let ptr1 = v.as_mut_ptr(); + /// ptr1.write(1); + /// let ptr2 = v.as_mut_ptr(); + /// ptr2.write(2); + /// // Notably, the write to `ptr2` did *not* invalidate `ptr1`: + /// ptr1.write(3); + /// } + /// ``` + /// + /// [`as_mut_ptr`]: Vec::as_mut_ptr + /// [`as_ptr`]: Vec::as_ptr #[stable(feature = "vec_as_ptr", since = "1.37.0")] + #[cfg_attr(not(bootstrap), rustc_never_returns_null_ptr)] #[inline] pub fn as_mut_ptr(&mut self) -> *mut T { // We shadow the slice method of the same name to avoid going through @@ -3404,6 +3457,36 @@ impl<T: Clone> From<&mut [T]> for Vec<T> { } #[cfg(not(no_global_oom_handling))] +#[stable(feature = "vec_from_array_ref", since = "1.74.0")] +impl<T: Clone, const N: usize> From<&[T; N]> for Vec<T> { + /// Allocate a `Vec<T>` and fill it by cloning `s`'s items. + /// + /// # Examples + /// + /// ``` + /// assert_eq!(Vec::from(&[1, 2, 3]), vec![1, 2, 3]); + /// ``` + fn from(s: &[T; N]) -> Vec<T> { + Self::from(s.as_slice()) + } +} + +#[cfg(not(no_global_oom_handling))] +#[stable(feature = "vec_from_array_ref", since = "1.74.0")] +impl<T: Clone, const N: usize> From<&mut [T; N]> for Vec<T> { + /// Allocate a `Vec<T>` and fill it by cloning `s`'s items. + /// + /// # Examples + /// + /// ``` + /// assert_eq!(Vec::from(&mut [1, 2, 3]), vec![1, 2, 3]); + /// ``` + fn from(s: &mut [T; N]) -> Vec<T> { + Self::from(s.as_mut_slice()) + } +} + +#[cfg(not(no_global_oom_handling))] #[stable(feature = "vec_from_array", since = "1.44.0")] impl<T, const N: usize> From<[T; N]> for Vec<T> { /// Allocate a `Vec<T>` and move `s`'s items into it. |