diff options
Diffstat (limited to 'library/alloc')
30 files changed, 733 insertions, 197 deletions
diff --git a/library/alloc/benches/lib.rs b/library/alloc/benches/lib.rs index 72ac897d4..d418965cd 100644 --- a/library/alloc/benches/lib.rs +++ b/library/alloc/benches/lib.rs @@ -3,7 +3,6 @@ #![cfg(not(target_os = "android"))] #![feature(btree_drain_filter)] #![feature(iter_next_chunk)] -#![feature(map_first_last)] #![feature(repr_simd)] #![feature(slice_partition_dedup)] #![feature(test)] diff --git a/library/alloc/src/alloc.rs b/library/alloc/src/alloc.rs index 80b067812..8187517cc 100644 --- a/library/alloc/src/alloc.rs +++ b/library/alloc/src/alloc.rs @@ -28,16 +28,20 @@ extern "Rust" { // The rustc fork of LLVM 14 and earlier also special-cases these function names to be able to optimize them // like `malloc`, `realloc`, and `free`, respectively. #[rustc_allocator] - #[rustc_allocator_nounwind] + #[cfg_attr(not(bootstrap), rustc_nounwind)] + #[cfg_attr(bootstrap, rustc_allocator_nounwind)] fn __rust_alloc(size: usize, align: usize) -> *mut u8; #[rustc_deallocator] - #[rustc_allocator_nounwind] + #[cfg_attr(not(bootstrap), rustc_nounwind)] + #[cfg_attr(bootstrap, rustc_allocator_nounwind)] fn __rust_dealloc(ptr: *mut u8, size: usize, align: usize); #[rustc_reallocator] - #[rustc_allocator_nounwind] + #[cfg_attr(not(bootstrap), rustc_nounwind)] + #[cfg_attr(bootstrap, rustc_allocator_nounwind)] fn __rust_realloc(ptr: *mut u8, old_size: usize, align: usize, new_size: usize) -> *mut u8; #[rustc_allocator_zeroed] - #[rustc_allocator_nounwind] + #[cfg_attr(not(bootstrap), rustc_nounwind)] + #[cfg_attr(bootstrap, rustc_allocator_nounwind)] fn __rust_alloc_zeroed(size: usize, align: usize) -> *mut u8; } diff --git a/library/alloc/src/borrow.rs b/library/alloc/src/borrow.rs index 904a53bb4..83a138559 100644 --- a/library/alloc/src/borrow.rs +++ b/library/alloc/src/borrow.rs @@ -21,7 +21,6 @@ use Cow::*; impl<'a, B: ?Sized> Borrow<B> for Cow<'a, B> where B: ToOwned, - <B as ToOwned>::Owned: 'a, { fn borrow(&self) -> &B { &**self diff --git a/library/alloc/src/boxed.rs b/library/alloc/src/boxed.rs index 65e323c9e..d6681a317 100644 --- a/library/alloc/src/boxed.rs +++ b/library/alloc/src/boxed.rs @@ -151,7 +151,6 @@ use core::async_iter::AsyncIterator; use core::borrow; use core::cmp::Ordering; use core::convert::{From, TryFrom}; -#[cfg(not(bootstrap))] use core::error::Error; use core::fmt; use core::future::Future; @@ -176,7 +175,6 @@ use crate::borrow::Cow; use crate::raw_vec::RawVec; #[cfg(not(no_global_oom_handling))] use crate::str::from_boxed_utf8_unchecked; -#[cfg(not(bootstrap))] #[cfg(not(no_global_oom_handling))] use crate::string::String; #[cfg(not(no_global_oom_handling))] @@ -1622,6 +1620,22 @@ impl<T, const N: usize> From<[T; N]> for Box<[T]> { } } +/// Casts a boxed slice to a boxed array. +/// +/// # Safety +/// +/// `boxed_slice.len()` must be exactly `N`. +unsafe fn boxed_slice_as_array_unchecked<T, A: Allocator, const N: usize>( + boxed_slice: Box<[T], A>, +) -> Box<[T; N], A> { + debug_assert_eq!(boxed_slice.len(), N); + + let (ptr, alloc) = Box::into_raw_with_allocator(boxed_slice); + // SAFETY: Pointer and allocator came from an existing box, + // and our safety condition requires that the length is exactly `N` + unsafe { Box::from_raw_in(ptr as *mut [T; N], alloc) } +} + #[stable(feature = "boxed_slice_try_from", since = "1.43.0")] impl<T, const N: usize> TryFrom<Box<[T]>> for Box<[T; N]> { type Error = Box<[T]>; @@ -1637,13 +1651,46 @@ impl<T, const N: usize> TryFrom<Box<[T]>> for Box<[T; N]> { /// `boxed_slice.len()` does not equal `N`. fn try_from(boxed_slice: Box<[T]>) -> Result<Self, Self::Error> { if boxed_slice.len() == N { - Ok(unsafe { Box::from_raw(Box::into_raw(boxed_slice) as *mut [T; N]) }) + Ok(unsafe { boxed_slice_as_array_unchecked(boxed_slice) }) } else { Err(boxed_slice) } } } +#[cfg(not(no_global_oom_handling))] +#[stable(feature = "boxed_array_try_from_vec", since = "1.66.0")] +impl<T, const N: usize> TryFrom<Vec<T>> for Box<[T; N]> { + type Error = Vec<T>; + + /// Attempts to convert a `Vec<T>` into a `Box<[T; N]>`. + /// + /// Like [`Vec::into_boxed_slice`], this is in-place if `vec.capacity() == N`, + /// but will require a reallocation otherwise. + /// + /// # Errors + /// + /// Returns the original `Vec<T>` in the `Err` variant if + /// `boxed_slice.len()` does not equal `N`. + /// + /// # Examples + /// + /// This can be used with [`vec!`] to create an array on the heap: + /// + /// ``` + /// let state: Box<[f32; 100]> = vec![1.0; 100].try_into().unwrap(); + /// assert_eq!(state.len(), 100); + /// ``` + fn try_from(vec: Vec<T>) -> Result<Self, Self::Error> { + if vec.len() == N { + let boxed_slice = vec.into_boxed_slice(); + Ok(unsafe { boxed_slice_as_array_unchecked(boxed_slice) }) + } else { + Err(vec) + } + } +} + impl<A: Allocator> Box<dyn Any, A> { /// Attempt to downcast the box to a concrete type. /// @@ -2037,8 +2084,7 @@ impl<T: ?Sized, A: Allocator> AsMut<T> for Box<T, A> { * could have a method to project a Pin<T> from it. */ #[stable(feature = "pin", since = "1.33.0")] -#[rustc_const_unstable(feature = "const_box", issue = "92521")] -impl<T: ?Sized, A: Allocator> const Unpin for Box<T, A> where A: 'static {} +impl<T: ?Sized, A: Allocator> Unpin for Box<T, A> where A: 'static {} #[unstable(feature = "generator_trait", issue = "43122")] impl<G: ?Sized + Generator<R> + Unpin, R, A: Allocator> Generator<R> for Box<G, A> @@ -2091,7 +2137,6 @@ impl<S: ?Sized + AsyncIterator + Unpin> AsyncIterator for Box<S> { } } -#[cfg(not(bootstrap))] impl dyn Error { #[inline] #[stable(feature = "error_downcast", since = "1.3.0")] @@ -2109,7 +2154,6 @@ impl dyn Error { } } -#[cfg(not(bootstrap))] impl dyn Error + Send { #[inline] #[stable(feature = "error_downcast", since = "1.3.0")] @@ -2124,7 +2168,6 @@ impl dyn Error + Send { } } -#[cfg(not(bootstrap))] impl dyn Error + Send + Sync { #[inline] #[stable(feature = "error_downcast", since = "1.3.0")] @@ -2139,7 +2182,6 @@ impl dyn Error + Send + Sync { } } -#[cfg(not(bootstrap))] #[cfg(not(no_global_oom_handling))] #[stable(feature = "rust1", since = "1.0.0")] impl<'a, E: Error + 'a> From<E> for Box<dyn Error + 'a> { @@ -2173,7 +2215,6 @@ impl<'a, E: Error + 'a> From<E> for Box<dyn Error + 'a> { } } -#[cfg(not(bootstrap))] #[cfg(not(no_global_oom_handling))] #[stable(feature = "rust1", since = "1.0.0")] impl<'a, E: Error + Send + Sync + 'a> From<E> for Box<dyn Error + Send + Sync + 'a> { @@ -2213,7 +2254,6 @@ impl<'a, E: Error + Send + Sync + 'a> From<E> for Box<dyn Error + Send + Sync + } } -#[cfg(not(bootstrap))] #[cfg(not(no_global_oom_handling))] #[stable(feature = "rust1", since = "1.0.0")] impl From<String> for Box<dyn Error + Send + Sync> { @@ -2258,7 +2298,6 @@ impl From<String> for Box<dyn Error + Send + Sync> { } } -#[cfg(not(bootstrap))] #[cfg(not(no_global_oom_handling))] #[stable(feature = "string_box_error", since = "1.6.0")] impl From<String> for Box<dyn Error> { @@ -2281,7 +2320,6 @@ impl From<String> for Box<dyn Error> { } } -#[cfg(not(bootstrap))] #[cfg(not(no_global_oom_handling))] #[stable(feature = "rust1", since = "1.0.0")] impl<'a> From<&str> for Box<dyn Error + Send + Sync + 'a> { @@ -2306,7 +2344,6 @@ impl<'a> From<&str> for Box<dyn Error + Send + Sync + 'a> { } } -#[cfg(not(bootstrap))] #[cfg(not(no_global_oom_handling))] #[stable(feature = "string_box_error", since = "1.6.0")] impl From<&str> for Box<dyn Error> { @@ -2329,7 +2366,6 @@ impl From<&str> for Box<dyn Error> { } } -#[cfg(not(bootstrap))] #[cfg(not(no_global_oom_handling))] #[stable(feature = "cow_box_error", since = "1.22.0")] impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + Send + Sync + 'a> { @@ -2352,7 +2388,6 @@ impl<'a, 'b> From<Cow<'b, str>> for Box<dyn Error + Send + Sync + 'a> { } } -#[cfg(not(bootstrap))] #[cfg(not(no_global_oom_handling))] #[stable(feature = "cow_box_error", since = "1.22.0")] impl<'a> From<Cow<'a, str>> for Box<dyn Error> { @@ -2374,7 +2409,6 @@ impl<'a> From<Cow<'a, str>> for Box<dyn Error> { } } -#[cfg(not(bootstrap))] #[stable(feature = "box_error", since = "1.8.0")] impl<T: core::error::Error> core::error::Error for Box<T> { #[allow(deprecated, deprecated_in_future)] diff --git a/library/alloc/src/boxed/thin.rs b/library/alloc/src/boxed/thin.rs index 0a20c74b0..c477c4490 100644 --- a/library/alloc/src/boxed/thin.rs +++ b/library/alloc/src/boxed/thin.rs @@ -2,7 +2,6 @@ // https://github.com/matthieu-m/rfc2580/blob/b58d1d3cba0d4b5e859d3617ea2d0943aaa31329/examples/thin.rs // by matthieu-m use crate::alloc::{self, Layout, LayoutError}; -#[cfg(not(bootstrap))] use core::error::Error; use core::fmt::{self, Debug, Display, Formatter}; use core::marker::PhantomData; @@ -274,7 +273,6 @@ impl<H> WithHeader<H> { } } -#[cfg(not(bootstrap))] #[unstable(feature = "thin_box", issue = "92791")] impl<T: ?Sized + Error> Error for ThinBox<T> { fn source(&self) -> Option<&(dyn Error + 'static)> { diff --git a/library/alloc/src/collections/btree/map.rs b/library/alloc/src/collections/btree/map.rs index cacbd54b6..8a7719347 100644 --- a/library/alloc/src/collections/btree/map.rs +++ b/library/alloc/src/collections/btree/map.rs @@ -580,7 +580,7 @@ impl<K, V> BTreeMap<K, V> { /// map.insert(1, "a"); /// ``` #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_btree_new", issue = "71835")] + #[rustc_const_stable(feature = "const_btree_new", since = "1.66.0")] #[must_use] pub const fn new() -> BTreeMap<K, V> { BTreeMap { root: None, length: 0, alloc: ManuallyDrop::new(Global), _marker: PhantomData } @@ -703,7 +703,6 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// Basic usage: /// /// ``` - /// #![feature(map_first_last)] /// use std::collections::BTreeMap; /// /// let mut map = BTreeMap::new(); @@ -712,7 +711,7 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// map.insert(2, "a"); /// assert_eq!(map.first_key_value(), Some((&1, &"b"))); /// ``` - #[unstable(feature = "map_first_last", issue = "62924")] + #[stable(feature = "map_first_last", since = "1.66.0")] pub fn first_key_value(&self) -> Option<(&K, &V)> where K: Ord, @@ -727,7 +726,6 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// # Examples /// /// ``` - /// #![feature(map_first_last)] /// use std::collections::BTreeMap; /// /// let mut map = BTreeMap::new(); @@ -741,7 +739,7 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// assert_eq!(*map.get(&1).unwrap(), "first"); /// assert_eq!(*map.get(&2).unwrap(), "b"); /// ``` - #[unstable(feature = "map_first_last", issue = "62924")] + #[stable(feature = "map_first_last", since = "1.66.0")] pub fn first_entry(&mut self) -> Option<OccupiedEntry<'_, K, V, A>> where K: Ord, @@ -765,7 +763,6 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// Draining elements in ascending order, while keeping a usable map each iteration. /// /// ``` - /// #![feature(map_first_last)] /// use std::collections::BTreeMap; /// /// let mut map = BTreeMap::new(); @@ -776,7 +773,7 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// } /// assert!(map.is_empty()); /// ``` - #[unstable(feature = "map_first_last", issue = "62924")] + #[stable(feature = "map_first_last", since = "1.66.0")] pub fn pop_first(&mut self) -> Option<(K, V)> where K: Ord, @@ -792,7 +789,6 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// Basic usage: /// /// ``` - /// #![feature(map_first_last)] /// use std::collections::BTreeMap; /// /// let mut map = BTreeMap::new(); @@ -800,7 +796,7 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// map.insert(2, "a"); /// assert_eq!(map.last_key_value(), Some((&2, &"a"))); /// ``` - #[unstable(feature = "map_first_last", issue = "62924")] + #[stable(feature = "map_first_last", since = "1.66.0")] pub fn last_key_value(&self) -> Option<(&K, &V)> where K: Ord, @@ -815,7 +811,6 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// # Examples /// /// ``` - /// #![feature(map_first_last)] /// use std::collections::BTreeMap; /// /// let mut map = BTreeMap::new(); @@ -829,7 +824,7 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// assert_eq!(*map.get(&1).unwrap(), "a"); /// assert_eq!(*map.get(&2).unwrap(), "last"); /// ``` - #[unstable(feature = "map_first_last", issue = "62924")] + #[stable(feature = "map_first_last", since = "1.66.0")] pub fn last_entry(&mut self) -> Option<OccupiedEntry<'_, K, V, A>> where K: Ord, @@ -853,7 +848,6 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// Draining elements in descending order, while keeping a usable map each iteration. /// /// ``` - /// #![feature(map_first_last)] /// use std::collections::BTreeMap; /// /// let mut map = BTreeMap::new(); @@ -864,7 +858,7 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// } /// assert!(map.is_empty()); /// ``` - #[unstable(feature = "map_first_last", issue = "62924")] + #[stable(feature = "map_first_last", since = "1.66.0")] pub fn pop_last(&mut self) -> Option<(K, V)> where K: Ord, @@ -1099,6 +1093,9 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// Moves all elements from `other` into `self`, leaving `other` empty. /// + /// If a key from `other` is already present in `self`, the respective + /// value from `self` will be overwritten with the respective value from `other`. + /// /// # Examples /// /// ``` @@ -1107,10 +1104,10 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// let mut a = BTreeMap::new(); /// a.insert(1, "a"); /// a.insert(2, "b"); - /// a.insert(3, "c"); + /// a.insert(3, "c"); // Note: Key (3) also present in b. /// /// let mut b = BTreeMap::new(); - /// b.insert(3, "d"); + /// b.insert(3, "d"); // Note: Key (3) also present in a. /// b.insert(4, "e"); /// b.insert(5, "f"); /// @@ -1121,7 +1118,7 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// /// assert_eq!(a[&1], "a"); /// assert_eq!(a[&2], "b"); - /// assert_eq!(a[&3], "d"); + /// assert_eq!(a[&3], "d"); // Note: "c" has been overwritten. /// assert_eq!(a[&4], "e"); /// assert_eq!(a[&5], "f"); /// ``` @@ -2392,7 +2389,11 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// ``` #[must_use] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_btree_new", issue = "71835")] + #[rustc_const_unstable( + feature = "const_btree_len", + issue = "71835", + implied_by = "const_btree_new" + )] pub const fn len(&self) -> usize { self.length } @@ -2413,7 +2414,11 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> { /// ``` #[must_use] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_btree_new", issue = "71835")] + #[rustc_const_unstable( + feature = "const_btree_len", + issue = "71835", + implied_by = "const_btree_new" + )] pub const fn is_empty(&self) -> bool { self.len() == 0 } diff --git a/library/alloc/src/collections/btree/map/entry.rs b/library/alloc/src/collections/btree/map/entry.rs index cd7cdc192..370b58864 100644 --- a/library/alloc/src/collections/btree/map/entry.rs +++ b/library/alloc/src/collections/btree/map/entry.rs @@ -133,7 +133,6 @@ impl<'a, K: Debug + Ord, V: Debug, A: Allocator + Clone> fmt::Display } } -#[cfg(not(bootstrap))] #[unstable(feature = "map_try_insert", issue = "82766")] impl<'a, K: core::fmt::Debug + Ord, V: core::fmt::Debug> core::error::Error for crate::collections::btree_map::OccupiedError<'a, K, V> diff --git a/library/alloc/src/collections/btree/node.rs b/library/alloc/src/collections/btree/node.rs index f1d2d3b30..da766b67a 100644 --- a/library/alloc/src/collections/btree/node.rs +++ b/library/alloc/src/collections/btree/node.rs @@ -206,9 +206,9 @@ impl<'a, K: 'a, V: 'a, Type> Clone for NodeRef<marker::Immut<'a>, K, V, Type> { unsafe impl<BorrowType, K: Sync, V: Sync, Type> Sync for NodeRef<BorrowType, K, V, Type> {} -unsafe impl<'a, K: Sync + 'a, V: Sync + 'a, Type> Send for NodeRef<marker::Immut<'a>, K, V, Type> {} -unsafe impl<'a, K: Send + 'a, V: Send + 'a, Type> Send for NodeRef<marker::Mut<'a>, K, V, Type> {} -unsafe impl<'a, K: Send + 'a, V: Send + 'a, Type> Send for NodeRef<marker::ValMut<'a>, K, V, Type> {} +unsafe impl<K: Sync, V: Sync, Type> Send for NodeRef<marker::Immut<'_>, K, V, Type> {} +unsafe impl<K: Send, V: Send, Type> Send for NodeRef<marker::Mut<'_>, K, V, Type> {} +unsafe impl<K: Send, V: Send, Type> Send for NodeRef<marker::ValMut<'_>, K, V, Type> {} unsafe impl<K: Send, V: Send, Type> Send for NodeRef<marker::Owned, K, V, Type> {} unsafe impl<K: Send, V: Send, Type> Send for NodeRef<marker::Dying, K, V, Type> {} diff --git a/library/alloc/src/collections/btree/set.rs b/library/alloc/src/collections/btree/set.rs index 2cfc08074..4ddb21192 100644 --- a/library/alloc/src/collections/btree/set.rs +++ b/library/alloc/src/collections/btree/set.rs @@ -343,7 +343,7 @@ impl<T> BTreeSet<T> { /// let mut set: BTreeSet<i32> = BTreeSet::new(); /// ``` #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_btree_new", issue = "71835")] + #[rustc_const_stable(feature = "const_btree_new", since = "1.66.0")] #[must_use] pub const fn new() -> BTreeSet<T> { BTreeSet { map: BTreeMap::new() } @@ -786,7 +786,6 @@ impl<T, A: Allocator + Clone> BTreeSet<T, A> { /// Basic usage: /// /// ``` - /// #![feature(map_first_last)] /// use std::collections::BTreeSet; /// /// let mut set = BTreeSet::new(); @@ -797,7 +796,7 @@ impl<T, A: Allocator + Clone> BTreeSet<T, A> { /// assert_eq!(set.first(), Some(&1)); /// ``` #[must_use] - #[unstable(feature = "map_first_last", issue = "62924")] + #[stable(feature = "map_first_last", since = "1.66.0")] pub fn first(&self) -> Option<&T> where T: Ord, @@ -813,7 +812,6 @@ impl<T, A: Allocator + Clone> BTreeSet<T, A> { /// Basic usage: /// /// ``` - /// #![feature(map_first_last)] /// use std::collections::BTreeSet; /// /// let mut set = BTreeSet::new(); @@ -824,7 +822,7 @@ impl<T, A: Allocator + Clone> BTreeSet<T, A> { /// assert_eq!(set.last(), Some(&2)); /// ``` #[must_use] - #[unstable(feature = "map_first_last", issue = "62924")] + #[stable(feature = "map_first_last", since = "1.66.0")] pub fn last(&self) -> Option<&T> where T: Ord, @@ -838,7 +836,6 @@ impl<T, A: Allocator + Clone> BTreeSet<T, A> { /// # Examples /// /// ``` - /// #![feature(map_first_last)] /// use std::collections::BTreeSet; /// /// let mut set = BTreeSet::new(); @@ -849,7 +846,7 @@ impl<T, A: Allocator + Clone> BTreeSet<T, A> { /// } /// assert!(set.is_empty()); /// ``` - #[unstable(feature = "map_first_last", issue = "62924")] + #[stable(feature = "map_first_last", since = "1.66.0")] pub fn pop_first(&mut self) -> Option<T> where T: Ord, @@ -863,7 +860,6 @@ impl<T, A: Allocator + Clone> BTreeSet<T, A> { /// # Examples /// /// ``` - /// #![feature(map_first_last)] /// use std::collections::BTreeSet; /// /// let mut set = BTreeSet::new(); @@ -874,7 +870,7 @@ impl<T, A: Allocator + Clone> BTreeSet<T, A> { /// } /// assert!(set.is_empty()); /// ``` - #[unstable(feature = "map_first_last", issue = "62924")] + #[stable(feature = "map_first_last", since = "1.66.0")] pub fn pop_last(&mut self) -> Option<T> where T: Ord, @@ -1174,7 +1170,11 @@ impl<T, A: Allocator + Clone> BTreeSet<T, A> { /// ``` #[must_use] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_btree_new", issue = "71835")] + #[rustc_const_unstable( + feature = "const_btree_len", + issue = "71835", + implied_by = "const_btree_new" + )] pub const fn len(&self) -> usize { self.map.len() } @@ -1193,7 +1193,11 @@ impl<T, A: Allocator + Clone> BTreeSet<T, A> { /// ``` #[must_use] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_btree_new", issue = "71835")] + #[rustc_const_unstable( + feature = "const_btree_len", + issue = "71835", + implied_by = "const_btree_new" + )] pub const fn is_empty(&self) -> bool { self.len() == 0 } diff --git a/library/alloc/src/collections/linked_list.rs b/library/alloc/src/collections/linked_list.rs index 6480fcaf9..f2f5dffc2 100644 --- a/library/alloc/src/collections/linked_list.rs +++ b/library/alloc/src/collections/linked_list.rs @@ -1613,7 +1613,7 @@ impl<'a, T> CursorMut<'a, T> { None } else { // We can't point to the node that we pop. Copying the behavior of - // `remove_current`, we move on the the next node in the sequence. + // `remove_current`, we move on to the next node in the sequence. // If the list is of length 1 then we end pointing to the "ghost" // node at index 0, which is expected. if self.list.head == self.current { diff --git a/library/alloc/src/collections/mod.rs b/library/alloc/src/collections/mod.rs index 21d0def08..161a37573 100644 --- a/library/alloc/src/collections/mod.rs +++ b/library/alloc/src/collections/mod.rs @@ -153,6 +153,5 @@ trait SpecExtend<I: IntoIterator> { fn spec_extend(&mut self, iter: I); } -#[cfg(not(bootstrap))] #[stable(feature = "try_reserve", since = "1.57.0")] impl core::error::Error for TryReserveError {} diff --git a/library/alloc/src/collections/vec_deque/mod.rs b/library/alloc/src/collections/vec_deque/mod.rs index e3f4deb08..2a57dad89 100644 --- a/library/alloc/src/collections/vec_deque/mod.rs +++ b/library/alloc/src/collections/vec_deque/mod.rs @@ -12,11 +12,17 @@ use core::fmt; use core::hash::{Hash, Hasher}; use core::iter::{repeat_with, FromIterator}; use core::marker::PhantomData; -use core::mem::{self, ManuallyDrop, MaybeUninit}; +use core::mem::{ManuallyDrop, MaybeUninit, SizedTypeProperties}; use core::ops::{Index, IndexMut, Range, RangeBounds}; use core::ptr::{self, NonNull}; use core::slice; +// This is used in a bunch of intra-doc links. +// FIXME: For some reason, `#[cfg(doc)]` wasn't sufficient, resulting in +// failures in linkchecker even though rustdoc built the docs just fine. +#[allow(unused_imports)] +use core::mem; + use crate::alloc::{Allocator, Global}; use crate::collections::TryReserveError; use crate::collections::TryReserveErrorKind; @@ -177,7 +183,7 @@ impl<T, A: Allocator> VecDeque<T, A> { /// Marginally more convenient #[inline] fn cap(&self) -> usize { - if mem::size_of::<T>() == 0 { + if T::IS_ZST { // For zero sized types, we are always at maximum capacity MAXIMUM_ZST_CAPACITY } else { @@ -3038,7 +3044,7 @@ impl<T, A: Allocator> From<Vec<T, A>> for VecDeque<T, A> { /// `Vec<T>` came from `From<VecDeque<T>>` and hasn't been reallocated. fn from(mut other: Vec<T, A>) -> Self { let len = other.len(); - if mem::size_of::<T>() == 0 { + if T::IS_ZST { // There's no actual allocation for ZSTs to worry about capacity, // but `VecDeque` can't handle as much length as `Vec`. assert!(len < MAXIMUM_ZST_CAPACITY, "capacity overflow"); @@ -3124,7 +3130,7 @@ impl<T, const N: usize> From<[T; N]> for VecDeque<T> { fn from(arr: [T; N]) -> Self { let mut deq = VecDeque::with_capacity(N); let arr = ManuallyDrop::new(arr); - if mem::size_of::<T>() != 0 { + if !<T>::IS_ZST { // SAFETY: VecDeque::with_capacity ensures that there is enough capacity. unsafe { ptr::copy_nonoverlapping(arr.as_ptr(), deq.ptr(), N); diff --git a/library/alloc/src/ffi/c_str.rs b/library/alloc/src/ffi/c_str.rs index aede6d54c..11bd4c4dc 100644 --- a/library/alloc/src/ffi/c_str.rs +++ b/library/alloc/src/ffi/c_str.rs @@ -1122,7 +1122,6 @@ impl CStr { } } -#[cfg(not(bootstrap))] #[stable(feature = "rust1", since = "1.0.0")] impl core::error::Error for NulError { #[allow(deprecated)] @@ -1131,11 +1130,9 @@ impl core::error::Error for NulError { } } -#[cfg(not(bootstrap))] #[stable(feature = "cstring_from_vec_with_nul", since = "1.58.0")] impl core::error::Error for FromVecWithNulError {} -#[cfg(not(bootstrap))] #[stable(feature = "cstring_into", since = "1.7.0")] impl core::error::Error for IntoStringError { #[allow(deprecated)] diff --git a/library/alloc/src/fmt.rs b/library/alloc/src/fmt.rs index ed398b566..799ce9d5d 100644 --- a/library/alloc/src/fmt.rs +++ b/library/alloc/src/fmt.rs @@ -327,7 +327,7 @@ //! - `text` must not contain any `'{'` or `'}'` characters, //! - `ws` is any character for which [`char::is_whitespace`] returns `true`, has no semantic //! meaning and is completely optional, -//! - `integer` is a decimal integer that may contain leading zeroes and +//! - `integer` is a decimal integer that may contain leading zeroes and must fit into an `usize` and //! - `identifier` is an `IDENTIFIER_OR_KEYWORD` (not an `IDENTIFIER`) as defined by the [Rust language reference](https://doc.rust-lang.org/reference/identifiers.html). //! //! # Formatting traits diff --git a/library/alloc/src/lib.rs b/library/alloc/src/lib.rs index 8619467c2..ce36b116f 100644 --- a/library/alloc/src/lib.rs +++ b/library/alloc/src/lib.rs @@ -69,6 +69,8 @@ any(not(feature = "miri-test-libstd"), test, doctest), no_global_oom_handling, not(no_global_oom_handling), + not(no_rc), + not(no_sync), target_has_atomic = "ptr" ))] #![no_std] @@ -97,7 +99,7 @@ #![feature(coerce_unsized)] #![cfg_attr(not(no_global_oom_handling), feature(const_alloc_error))] #![feature(const_box)] -#![cfg_attr(not(no_global_oom_handling), feature(const_btree_new))] +#![cfg_attr(not(no_global_oom_handling), feature(const_btree_len))] #![feature(const_cow_is_borrowed)] #![feature(const_convert)] #![feature(const_size_of_val)] @@ -109,10 +111,11 @@ #![feature(core_intrinsics)] #![feature(const_eval_select)] #![feature(const_pin)] +#![feature(const_waker)] #![feature(cstr_from_bytes_until_nul)] #![feature(dispatch_from_dyn)] -#![cfg_attr(not(bootstrap), feature(error_generic_member_access))] -#![cfg_attr(not(bootstrap), feature(error_in_core))] +#![feature(error_generic_member_access)] +#![feature(error_in_core)] #![feature(exact_size_is_empty)] #![feature(extend_one)] #![feature(fmt_internals)] @@ -122,20 +125,21 @@ #![feature(iter_advance_by)] #![feature(iter_next_chunk)] #![feature(layout_for_ptr)] -#![feature(maybe_uninit_array_assume_init)] #![feature(maybe_uninit_slice)] #![feature(maybe_uninit_uninit_array)] +#![feature(maybe_uninit_uninit_array_transpose)] #![cfg_attr(test, feature(new_uninit))] #![feature(nonnull_slice_from_raw_parts)] #![feature(pattern)] #![feature(pointer_byte_offsets)] -#![cfg_attr(not(bootstrap), feature(provide_any))] +#![feature(provide_any)] #![feature(ptr_internals)] #![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)] #![feature(slice_group_by)] #![feature(slice_ptr_get)] @@ -169,7 +173,6 @@ #![cfg_attr(not(test), feature(generator_trait))] #![feature(hashmap_internals)] #![feature(lang_items)] -#![cfg_attr(bootstrap, feature(let_else))] #![feature(min_specialization)] #![feature(negative_impls)] #![feature(never_type)] @@ -224,16 +227,17 @@ mod boxed { } pub mod borrow; pub mod collections; -#[cfg(not(no_global_oom_handling))] +#[cfg(all(not(no_rc), not(no_sync), not(no_global_oom_handling)))] pub mod ffi; pub mod fmt; +#[cfg(not(no_rc))] pub mod rc; pub mod slice; pub mod str; pub mod string; -#[cfg(target_has_atomic = "ptr")] +#[cfg(all(not(no_rc), not(no_sync), target_has_atomic = "ptr"))] pub mod sync; -#[cfg(all(not(no_global_oom_handling), target_has_atomic = "ptr"))] +#[cfg(all(not(no_global_oom_handling), not(no_rc), not(no_sync), target_has_atomic = "ptr"))] pub mod task; #[cfg(test)] mod tests; diff --git a/library/alloc/src/raw_vec.rs b/library/alloc/src/raw_vec.rs index b0f4529ab..5a10121bb 100644 --- a/library/alloc/src/raw_vec.rs +++ b/library/alloc/src/raw_vec.rs @@ -3,7 +3,7 @@ use core::alloc::LayoutError; use core::cmp; use core::intrinsics; -use core::mem::{self, ManuallyDrop, MaybeUninit}; +use core::mem::{self, ManuallyDrop, MaybeUninit, SizedTypeProperties}; use core::ops::Drop; use core::ptr::{self, NonNull, Unique}; use core::slice; @@ -168,7 +168,7 @@ impl<T, A: Allocator> RawVec<T, A> { #[cfg(not(no_global_oom_handling))] fn allocate_in(capacity: usize, init: AllocInit, alloc: A) -> Self { // Don't allocate here because `Drop` will not deallocate when `capacity` is 0. - if mem::size_of::<T>() == 0 || capacity == 0 { + if T::IS_ZST || capacity == 0 { Self::new_in(alloc) } else { // We avoid `unwrap_or_else` here because it bloats the amount of @@ -229,7 +229,7 @@ impl<T, A: Allocator> RawVec<T, A> { /// This will always be `usize::MAX` if `T` is zero-sized. #[inline(always)] pub fn capacity(&self) -> usize { - if mem::size_of::<T>() == 0 { usize::MAX } else { self.cap } + if T::IS_ZST { usize::MAX } else { self.cap } } /// Returns a shared reference to the allocator backing this `RawVec`. @@ -238,7 +238,7 @@ impl<T, A: Allocator> RawVec<T, A> { } fn current_memory(&self) -> Option<(NonNull<u8>, Layout)> { - if mem::size_of::<T>() == 0 || self.cap == 0 { + if T::IS_ZST || self.cap == 0 { None } else { // We have an allocated chunk of memory, so we can bypass runtime @@ -380,7 +380,7 @@ impl<T, A: Allocator> RawVec<T, A> { // This is ensured by the calling contexts. debug_assert!(additional > 0); - if mem::size_of::<T>() == 0 { + if T::IS_ZST { // Since we return a capacity of `usize::MAX` when `elem_size` is // 0, getting to here necessarily means the `RawVec` is overfull. return Err(CapacityOverflow.into()); @@ -406,7 +406,7 @@ impl<T, A: Allocator> RawVec<T, A> { // `grow_amortized`, but this method is usually instantiated less often so // it's less critical. fn grow_exact(&mut self, len: usize, additional: usize) -> Result<(), TryReserveError> { - if mem::size_of::<T>() == 0 { + if T::IS_ZST { // Since we return a capacity of `usize::MAX` when the type size is // 0, getting to here necessarily means the `RawVec` is overfull. return Err(CapacityOverflow.into()); diff --git a/library/alloc/src/rc.rs b/library/alloc/src/rc.rs index 6d247681c..006d813e5 100644 --- a/library/alloc/src/rc.rs +++ b/library/alloc/src/rc.rs @@ -1110,8 +1110,8 @@ impl<T: ?Sized> Rc<T> { #[inline] #[stable(feature = "ptr_eq", since = "1.17.0")] - /// Returns `true` if the two `Rc`s point to the same allocation - /// (in a vein similar to [`ptr::eq`]). + /// Returns `true` if the two `Rc`s point to the same allocation in a vein similar to + /// [`ptr::eq`]. See [that function][`ptr::eq`] for caveats when comparing `dyn Trait` pointers. /// /// # Examples /// @@ -1386,7 +1386,7 @@ impl<T: ?Sized> Rc<T> { Self::allocate_for_layout( Layout::for_value(&*ptr), |layout| Global.allocate(layout), - |mem| mem.with_metadata_of(ptr as *mut RcBox<T>), + |mem| mem.with_metadata_of(ptr as *const RcBox<T>), ) } } @@ -2419,9 +2419,9 @@ impl<T: ?Sized> Weak<T> { } } - /// Returns `true` if the two `Weak`s point to the same allocation (similar to - /// [`ptr::eq`]), or if both don't point to any allocation - /// (because they were created with `Weak::new()`). + /// Returns `true` if the two `Weak`s point to the same allocation similar to [`ptr::eq`], or if + /// both don't point to any allocation (because they were created with `Weak::new()`). See [that + /// function][`ptr::eq`] for caveats when comparing `dyn Trait` pointers. /// /// # Notes /// diff --git a/library/alloc/src/slice.rs b/library/alloc/src/slice.rs index bcd3f49e2..a5e7bf2a1 100644 --- a/library/alloc/src/slice.rs +++ b/library/alloc/src/slice.rs @@ -16,9 +16,7 @@ use core::borrow::{Borrow, BorrowMut}; #[cfg(not(no_global_oom_handling))] use core::cmp::Ordering::{self, Less}; #[cfg(not(no_global_oom_handling))] -use core::mem; -#[cfg(not(no_global_oom_handling))] -use core::mem::size_of; +use core::mem::{self, SizedTypeProperties}; #[cfg(not(no_global_oom_handling))] use core::ptr; @@ -205,7 +203,7 @@ impl<T> [T] { where T: Ord, { - merge_sort(self, |a, b| a.lt(b)); + merge_sort(self, T::lt); } /// Sorts the slice with a comparator function. @@ -1018,7 +1016,7 @@ where const MIN_RUN: usize = 10; // Sorting has no meaningful behavior on zero-sized types. - if size_of::<T>() == 0 { + if T::IS_ZST { return; } diff --git a/library/alloc/src/string.rs b/library/alloc/src/string.rs index f2448396c..c436adf70 100644 --- a/library/alloc/src/string.rs +++ b/library/alloc/src/string.rs @@ -44,7 +44,6 @@ #[cfg(not(no_global_oom_handling))] use core::char::{decode_utf16, REPLACEMENT_CHARACTER}; -#[cfg(not(bootstrap))] use core::error::Error; use core::fmt; use core::hash; @@ -68,7 +67,7 @@ use core::str::Utf8Chunks; use crate::borrow::{Cow, ToOwned}; use crate::boxed::Box; use crate::collections::TryReserveError; -use crate::str::{self, Chars, Utf8Error}; +use crate::str::{self, from_utf8_unchecked_mut, Chars, Utf8Error}; #[cfg(not(no_global_oom_handling))] use crate::str::{from_boxed_utf8_unchecked, FromStr}; use crate::vec::Vec; @@ -1850,6 +1849,35 @@ impl String { let slice = self.vec.into_boxed_slice(); unsafe { from_boxed_utf8_unchecked(slice) } } + + /// Consumes and leaks the `String`, returning a mutable reference to the contents, + /// `&'static mut str`. + /// + /// This is mainly useful for data that lives for the remainder of + /// the program's life. Dropping the returned reference will cause a memory + /// leak. + /// + /// It does not reallocate or shrink the `String`, + /// so the leaked allocation may include unused capacity that is not part + /// of the returned slice. + /// + /// # Examples + /// + /// Simple usage: + /// + /// ``` + /// #![feature(string_leak)] + /// + /// let x = String::from("bucket"); + /// let static_ref: &'static mut str = x.leak(); + /// assert_eq!(static_ref, "bucket"); + /// ``` + #[unstable(feature = "string_leak", issue = "102929")] + #[inline] + pub fn leak(self) -> &'static mut str { + let slice = self.vec.leak(); + unsafe { from_utf8_unchecked_mut(slice) } + } } impl FromUtf8Error { @@ -1941,7 +1969,6 @@ impl fmt::Display for FromUtf16Error { } } -#[cfg(not(bootstrap))] #[stable(feature = "rust1", since = "1.0.0")] impl Error for FromUtf8Error { #[allow(deprecated)] @@ -1950,7 +1977,6 @@ impl Error for FromUtf8Error { } } -#[cfg(not(bootstrap))] #[stable(feature = "rust1", since = "1.0.0")] impl Error for FromUtf16Error { #[allow(deprecated)] diff --git a/library/alloc/src/sync.rs b/library/alloc/src/sync.rs index 4377edeee..81cd77074 100644 --- a/library/alloc/src/sync.rs +++ b/library/alloc/src/sync.rs @@ -3,6 +3,10 @@ //! Thread-safe reference-counting pointers. //! //! See the [`Arc<T>`][Arc] documentation for more details. +//! +//! **Note**: This module is only available on platforms that support atomic +//! loads and stores of pointers. This may be detected at compile time using +//! `#[cfg(target_has_atomic = "ptr")]`. use core::any::Any; use core::borrow; @@ -82,6 +86,11 @@ macro_rules! acquire { /// [`Mutex`][mutex], [`RwLock`][rwlock], or one of the [`Atomic`][atomic] /// types. /// +/// **Note**: This type is only available on platforms that support atomic +/// loads and stores of pointers, which includes all platforms that support +/// the `std` crate but not all those which only support [`alloc`](crate). +/// This may be detected at compile time using `#[cfg(target_has_atomic = "ptr")]`. +/// /// ## Thread Safety /// /// Unlike [`Rc<T>`], `Arc<T>` uses atomic operations for its reference @@ -1108,8 +1117,8 @@ impl<T: ?Sized> Arc<T> { drop(Weak { ptr: self.ptr }); } - /// Returns `true` if the two `Arc`s point to the same allocation - /// (in a vein similar to [`ptr::eq`]). + /// Returns `true` if the two `Arc`s point to the same allocation in a vein similar to + /// [`ptr::eq`]. See [that function][`ptr::eq`] for caveats when comparing `dyn Trait` pointers. /// /// # Examples /// @@ -1195,7 +1204,7 @@ impl<T: ?Sized> Arc<T> { Self::allocate_for_layout( Layout::for_value(&*ptr), |layout| Global.allocate(layout), - |mem| mem.with_metadata_of(ptr as *mut ArcInner<T>), + |mem| mem.with_metadata_of(ptr as *const ArcInner<T>), ) } } @@ -1980,33 +1989,26 @@ impl<T: ?Sized> Weak<T> { // We use a CAS loop to increment the strong count instead of a // fetch_add as this function should never take the reference count // from zero to one. - let inner = self.inner()?; - - // Relaxed load because any write of 0 that we can observe - // leaves the field in a permanently zero state (so a - // "stale" read of 0 is fine), and any other value is - // confirmed via the CAS below. - let mut n = inner.strong.load(Relaxed); - - loop { - if n == 0 { - return None; - } - - // See comments in `Arc::clone` for why we do this (for `mem::forget`). - if n > MAX_REFCOUNT { - abort(); - } - + self.inner()? + .strong // Relaxed is fine for the failure case because we don't have any expectations about the new state. // Acquire is necessary for the success case to synchronise with `Arc::new_cyclic`, when the inner // value can be initialized after `Weak` references have already been created. In that case, we // expect to observe the fully initialized value. - match inner.strong.compare_exchange_weak(n, n + 1, Acquire, Relaxed) { - Ok(_) => return Some(unsafe { Arc::from_inner(self.ptr) }), // null checked above - Err(old) => n = old, - } - } + .fetch_update(Acquire, Relaxed, |n| { + // Any write of 0 we can observe leaves the field in permanently zero state. + if n == 0 { + return None; + } + // See comments in `Arc::clone` for why we do this (for `mem::forget`). + if n > MAX_REFCOUNT { + abort(); + } + Some(n + 1) + }) + .ok() + // null checked above + .map(|_| unsafe { Arc::from_inner(self.ptr) }) } /// Gets the number of strong (`Arc`) pointers pointing to this allocation. @@ -2067,9 +2069,9 @@ impl<T: ?Sized> Weak<T> { } } - /// Returns `true` if the two `Weak`s point to the same allocation (similar to - /// [`ptr::eq`]), or if both don't point to any allocation - /// (because they were created with `Weak::new()`). + /// Returns `true` if the two `Weak`s point to the same allocation similar to [`ptr::eq`], or if + /// both don't point to any allocation (because they were created with `Weak::new()`). See [that + /// function][`ptr::eq`] for caveats when comparing `dyn Trait` pointers. /// /// # Notes /// @@ -2764,7 +2766,6 @@ fn data_offset_align(align: usize) -> usize { layout.size() + layout.padding_needed_for(align) } -#[cfg(not(bootstrap))] #[stable(feature = "arc_error", since = "1.52.0")] impl<T: core::error::Error + ?Sized> core::error::Error for Arc<T> { #[allow(deprecated, deprecated_in_future)] diff --git a/library/alloc/src/task.rs b/library/alloc/src/task.rs index 528ee4ff1..9d8e309a9 100644 --- a/library/alloc/src/task.rs +++ b/library/alloc/src/task.rs @@ -1,5 +1,11 @@ #![stable(feature = "wake_trait", since = "1.51.0")] + //! Types and Traits for working with asynchronous tasks. +//! +//! **Note**: This module is only available on platforms that support atomic +//! loads and stores of pointers. This may be detected at compile time using +//! `#[cfg(target_has_atomic = "ptr")]`. + use core::mem::ManuallyDrop; use core::task::{RawWaker, RawWakerVTable, Waker}; diff --git a/library/alloc/src/vec/drain.rs b/library/alloc/src/vec/drain.rs index 5b73906a1..541f99bcf 100644 --- a/library/alloc/src/vec/drain.rs +++ b/library/alloc/src/vec/drain.rs @@ -1,7 +1,7 @@ use crate::alloc::{Allocator, Global}; use core::fmt; use core::iter::{FusedIterator, TrustedLen}; -use core::mem::{self, ManuallyDrop}; +use core::mem::{self, ManuallyDrop, SizedTypeProperties}; use core::ptr::{self, NonNull}; use core::slice::{self}; @@ -202,7 +202,7 @@ impl<T, A: Allocator> Drop for Drain<'_, T, A> { let mut vec = self.vec; - if mem::size_of::<T>() == 0 { + if T::IS_ZST { // ZSTs have no identity, so we don't need to move them around, we only need to drop the correct amount. // this can be achieved by manipulating the Vec length instead of moving values out from `iter`. unsafe { diff --git a/library/alloc/src/vec/in_place_collect.rs b/library/alloc/src/vec/in_place_collect.rs index b211421b2..87d61deb1 100644 --- a/library/alloc/src/vec/in_place_collect.rs +++ b/library/alloc/src/vec/in_place_collect.rs @@ -55,6 +55,9 @@ //! This is handled by the [`InPlaceDrop`] guard for sink items (`U`) and by //! [`vec::IntoIter::forget_allocation_drop_remaining()`] for remaining source items (`T`). //! +//! If dropping any remaining source item (`T`) panics then [`InPlaceDstBufDrop`] will handle dropping +//! the already collected sink items (`U`) and freeing the allocation. +//! //! [`vec::IntoIter::forget_allocation_drop_remaining()`]: super::IntoIter::forget_allocation_drop_remaining() //! //! # O(1) collect @@ -135,10 +138,10 @@ //! vec.truncate(write_idx); //! ``` use core::iter::{InPlaceIterable, SourceIter, TrustedRandomAccessNoCoerce}; -use core::mem::{self, ManuallyDrop}; +use core::mem::{self, ManuallyDrop, SizedTypeProperties}; use core::ptr::{self}; -use super::{InPlaceDrop, SpecFromIter, SpecFromIterNested, Vec}; +use super::{InPlaceDrop, InPlaceDstBufDrop, SpecFromIter, SpecFromIterNested, Vec}; /// Specialization marker for collecting an iterator pipeline into a Vec while reusing the /// source allocation, i.e. executing the pipeline in place. @@ -154,7 +157,7 @@ where default fn from_iter(mut iterator: I) -> Self { // See "Layout constraints" section in the module documentation. We rely on const // optimization here since these conditions currently cannot be expressed as trait bounds - if mem::size_of::<T>() == 0 + if T::IS_ZST || mem::size_of::<T>() != mem::size_of::<<<I as SourceIter>::Source as AsVecIntoIter>::Item>() || mem::align_of::<T>() @@ -191,14 +194,17 @@ where ); } - // Drop any remaining values at the tail of the source but prevent drop of the allocation - // itself once IntoIter goes out of scope. - // If the drop panics then we also leak any elements collected into dst_buf. + // The ownership of the allocation and the new `T` values is temporarily moved into `dst_guard`. + // This is safe because `forget_allocation_drop_remaining` immediately forgets the allocation + // before any panic can occur in order to avoid any double free, and then proceeds to drop + // any remaining values at the tail of the source. // // Note: This access to the source wouldn't be allowed by the TrustedRandomIteratorNoCoerce // contract (used by SpecInPlaceCollect below). But see the "O(1) collect" section in the // module documenttation why this is ok anyway. + let dst_guard = InPlaceDstBufDrop { ptr: dst_buf, len, cap }; src.forget_allocation_drop_remaining(); + mem::forget(dst_guard); let vec = unsafe { Vec::from_raw_parts(dst_buf, len, cap) }; diff --git a/library/alloc/src/vec/in_place_drop.rs b/library/alloc/src/vec/in_place_drop.rs index 1b1ef9130..25ca33c6a 100644 --- a/library/alloc/src/vec/in_place_drop.rs +++ b/library/alloc/src/vec/in_place_drop.rs @@ -22,3 +22,18 @@ impl<T> Drop for InPlaceDrop<T> { } } } + +// A helper struct for in-place collection that drops the destination allocation and elements, +// to avoid leaking them if some other destructor panics. +pub(super) struct InPlaceDstBufDrop<T> { + pub(super) ptr: *mut T, + pub(super) len: usize, + pub(super) cap: usize, +} + +impl<T> Drop for InPlaceDstBufDrop<T> { + #[inline] + fn drop(&mut self) { + unsafe { super::Vec::from_raw_parts(self.ptr, self.len, self.cap) }; + } +} diff --git a/library/alloc/src/vec/into_iter.rs b/library/alloc/src/vec/into_iter.rs index b4157fd58..02cc7691a 100644 --- a/library/alloc/src/vec/into_iter.rs +++ b/library/alloc/src/vec/into_iter.rs @@ -8,7 +8,7 @@ use core::iter::{ FusedIterator, InPlaceIterable, SourceIter, TrustedLen, TrustedRandomAccessNoCoerce, }; use core::marker::PhantomData; -use core::mem::{self, ManuallyDrop, MaybeUninit}; +use core::mem::{self, ManuallyDrop, MaybeUninit, SizedTypeProperties}; #[cfg(not(no_global_oom_handling))] use core::ops::Deref; use core::ptr::{self, NonNull}; @@ -95,13 +95,16 @@ impl<T, A: Allocator> IntoIter<T, A> { } /// Drops remaining elements and relinquishes the backing allocation. + /// This method guarantees it won't panic before relinquishing + /// the backing allocation. /// /// This is roughly equivalent to the following, but more efficient /// /// ``` /// # let mut into_iter = Vec::<u8>::with_capacity(10).into_iter(); + /// let mut into_iter = std::mem::replace(&mut into_iter, Vec::new().into_iter()); /// (&mut into_iter).for_each(core::mem::drop); - /// unsafe { core::ptr::write(&mut into_iter, Vec::new().into_iter()); } + /// std::mem::forget(into_iter); /// ``` /// /// This method is used by in-place iteration, refer to the vec::in_place_collect @@ -118,6 +121,8 @@ impl<T, A: Allocator> IntoIter<T, A> { self.ptr = self.buf.as_ptr(); self.end = self.buf.as_ptr(); + // Dropping the remaining elements can panic, so this needs to be + // done only after updating the other fields. unsafe { ptr::drop_in_place(remaining); } @@ -149,7 +154,7 @@ impl<T, A: Allocator> Iterator for IntoIter<T, A> { fn next(&mut self) -> Option<T> { if self.ptr == self.end { None - } else if mem::size_of::<T>() == 0 { + } else if T::IS_ZST { // purposefully don't use 'ptr.offset' because for // vectors with 0-size elements this would return the // same pointer. @@ -167,7 +172,7 @@ impl<T, A: Allocator> Iterator for IntoIter<T, A> { #[inline] fn size_hint(&self) -> (usize, Option<usize>) { - let exact = if mem::size_of::<T>() == 0 { + let exact = if T::IS_ZST { self.end.addr().wrapping_sub(self.ptr.addr()) } else { unsafe { self.end.sub_ptr(self.ptr) } @@ -179,7 +184,7 @@ impl<T, A: Allocator> Iterator for IntoIter<T, A> { fn advance_by(&mut self, n: usize) -> Result<(), usize> { let step_size = self.len().min(n); let to_drop = ptr::slice_from_raw_parts_mut(self.ptr as *mut T, step_size); - if mem::size_of::<T>() == 0 { + if T::IS_ZST { // SAFETY: due to unchecked casts of unsigned amounts to signed offsets the wraparound // effectively results in unsigned pointers representing positions 0..usize::MAX, // which is valid for ZSTs. @@ -209,7 +214,7 @@ impl<T, A: Allocator> Iterator for IntoIter<T, A> { let len = self.len(); - if mem::size_of::<T>() == 0 { + if T::IS_ZST { if len < N { self.forget_remaining_elements(); // Safety: ZSTs can be conjured ex nihilo, only the amount has to be correct @@ -218,7 +223,7 @@ impl<T, A: Allocator> Iterator for IntoIter<T, A> { self.ptr = self.ptr.wrapping_byte_add(N); // Safety: ditto - return Ok(unsafe { MaybeUninit::array_assume_init(raw_ary) }); + return Ok(unsafe { raw_ary.transpose().assume_init() }); } if len < N { @@ -236,7 +241,7 @@ impl<T, A: Allocator> Iterator for IntoIter<T, A> { return unsafe { ptr::copy_nonoverlapping(self.ptr, raw_ary.as_mut_ptr() as *mut T, N); self.ptr = self.ptr.add(N); - Ok(MaybeUninit::array_assume_init(raw_ary)) + Ok(raw_ary.transpose().assume_init()) }; } @@ -253,7 +258,7 @@ impl<T, A: Allocator> Iterator for IntoIter<T, A> { // that `T: Copy` so reading elements from the buffer doesn't invalidate // them for `Drop`. unsafe { - if mem::size_of::<T>() == 0 { mem::zeroed() } else { ptr::read(self.ptr.add(i)) } + if T::IS_ZST { mem::zeroed() } else { ptr::read(self.ptr.add(i)) } } } } @@ -264,7 +269,7 @@ impl<T, A: Allocator> DoubleEndedIterator for IntoIter<T, A> { fn next_back(&mut self) -> Option<T> { if self.end == self.ptr { None - } else if mem::size_of::<T>() == 0 { + } else if T::IS_ZST { // See above for why 'ptr.offset' isn't used self.end = self.end.wrapping_byte_sub(1); @@ -280,7 +285,7 @@ impl<T, A: Allocator> DoubleEndedIterator for IntoIter<T, A> { #[inline] fn advance_back_by(&mut self, n: usize) -> Result<(), usize> { let step_size = self.len().min(n); - if mem::size_of::<T>() == 0 { + if T::IS_ZST { // SAFETY: same as for advance_by() self.end = self.end.wrapping_byte_sub(step_size); } else { diff --git a/library/alloc/src/vec/is_zero.rs b/library/alloc/src/vec/is_zero.rs index 2e025c8a4..8e652d676 100644 --- a/library/alloc/src/vec/is_zero.rs +++ b/library/alloc/src/vec/is_zero.rs @@ -160,3 +160,25 @@ unsafe impl<T: IsZero> IsZero for Saturating<T> { self.0.is_zero() } } + +macro_rules! impl_for_optional_bool { + ($($t:ty,)+) => {$( + unsafe impl IsZero for $t { + #[inline] + fn is_zero(&self) -> bool { + // SAFETY: This is *not* a stable layout guarantee, but + // inside `core` we're allowed to rely on the current rustc + // behaviour that options of bools will be one byte with + // no padding, so long as they're nested less than 254 deep. + let raw: u8 = unsafe { core::mem::transmute(*self) }; + raw == 0 + } + } + )+}; +} +impl_for_optional_bool! { + Option<bool>, + Option<Option<bool>>, + Option<Option<Option<bool>>>, + // Could go further, but not worth the metadata overhead +} diff --git a/library/alloc/src/vec/mod.rs b/library/alloc/src/vec/mod.rs index 60b36af5e..bbbdc3aa2 100644 --- a/library/alloc/src/vec/mod.rs +++ b/library/alloc/src/vec/mod.rs @@ -64,7 +64,7 @@ use core::iter; #[cfg(not(no_global_oom_handling))] use core::iter::FromIterator; use core::marker::PhantomData; -use core::mem::{self, ManuallyDrop, MaybeUninit}; +use core::mem::{self, ManuallyDrop, MaybeUninit, SizedTypeProperties}; use core::ops::{self, Index, IndexMut, Range, RangeBounds}; use core::ptr::{self, NonNull}; use core::slice::{self, SliceIndex}; @@ -125,7 +125,7 @@ use self::set_len_on_drop::SetLenOnDrop; mod set_len_on_drop; #[cfg(not(no_global_oom_handling))] -use self::in_place_drop::InPlaceDrop; +use self::in_place_drop::{InPlaceDrop, InPlaceDstBufDrop}; #[cfg(not(no_global_oom_handling))] mod in_place_drop; @@ -483,15 +483,13 @@ impl<T> Vec<T> { Self::with_capacity_in(capacity, Global) } - /// Creates a `Vec<T>` directly from the raw components of another vector. + /// Creates a `Vec<T>` directly from a pointer, a capacity, and a length. /// /// # Safety /// /// This is highly unsafe, due to the number of invariants that aren't /// checked: /// - /// * `ptr` needs to have been previously allocated via [`String`]/`Vec<T>` - /// (at least, it's highly likely to be incorrect if it wasn't). /// * `T` needs to have the same alignment as what `ptr` was allocated with. /// (`T` having a less strict alignment is not sufficient, the alignment really /// needs to be equal to satisfy the [`dealloc`] requirement that memory must be @@ -500,6 +498,14 @@ impl<T> Vec<T> { /// to be the same size as the pointer was allocated with. (Because similar to /// alignment, [`dealloc`] must be called with the same layout `size`.) /// * `length` needs to be less than or equal to `capacity`. + /// * The first `length` values must be properly initialized values of type `T`. + /// * `capacity` needs to be the capacity that the pointer was allocated with. + /// * The allocated size in bytes must be no larger than `isize::MAX`. + /// See the safety documentation of [`pointer::offset`]. + /// + /// These requirements are always upheld by any `ptr` that has been allocated + /// via `Vec<T>`. Other allocation sources are allowed if the invariants are + /// upheld. /// /// Violating these may cause problems like corrupting the allocator's /// internal data structures. For example it is normally **not** safe @@ -551,6 +557,32 @@ impl<T> Vec<T> { /// assert_eq!(rebuilt, [4, 5, 6]); /// } /// ``` + /// + /// Using memory that was allocated elsewhere: + /// + /// ```rust + /// #![feature(allocator_api)] + /// + /// use std::alloc::{AllocError, Allocator, Global, Layout}; + /// + /// fn main() { + /// let layout = Layout::array::<u32>(16).expect("overflow cannot happen"); + /// + /// let vec = unsafe { + /// let mem = match Global.allocate(layout) { + /// Ok(mem) => mem.cast::<u32>().as_ptr(), + /// Err(AllocError) => return, + /// }; + /// + /// mem.write(1_000_000); + /// + /// Vec::from_raw_parts_in(mem, 1, 16, Global) + /// }; + /// + /// assert_eq!(vec, &[1_000_000]); + /// assert_eq!(vec.capacity(), 16); + /// } + /// ``` #[inline] #[stable(feature = "rust1", since = "1.0.0")] pub unsafe fn from_raw_parts(ptr: *mut T, length: usize, capacity: usize) -> Self { @@ -641,21 +673,30 @@ impl<T, A: Allocator> Vec<T, A> { Vec { buf: RawVec::with_capacity_in(capacity, alloc), len: 0 } } - /// Creates a `Vec<T, A>` directly from the raw components of another vector. + /// Creates a `Vec<T, A>` directly from a pointer, a capacity, a length, + /// and an allocator. /// /// # Safety /// /// This is highly unsafe, due to the number of invariants that aren't /// checked: /// - /// * `ptr` needs to have been previously allocated via [`String`]/`Vec<T>` - /// (at least, it's highly likely to be incorrect if it wasn't). - /// * `T` needs to have the same size and alignment as what `ptr` was allocated with. + /// * `T` needs to have the same alignment as what `ptr` was allocated with. /// (`T` having a less strict alignment is not sufficient, the alignment really /// needs to be equal to satisfy the [`dealloc`] requirement that memory must be /// allocated and deallocated with the same layout.) + /// * The size of `T` times the `capacity` (ie. the allocated size in bytes) needs + /// to be the same size as the pointer was allocated with. (Because similar to + /// alignment, [`dealloc`] must be called with the same layout `size`.) /// * `length` needs to be less than or equal to `capacity`. - /// * `capacity` needs to be the capacity that the pointer was allocated with. + /// * The first `length` values must be properly initialized values of type `T`. + /// * `capacity` needs to [*fit*] the layout size that the pointer was allocated with. + /// * The allocated size in bytes must be no larger than `isize::MAX`. + /// See the safety documentation of [`pointer::offset`]. + /// + /// These requirements are always upheld by any `ptr` that has been allocated + /// via `Vec<T, A>`. Other allocation sources are allowed if the invariants are + /// upheld. /// /// Violating these may cause problems like corrupting the allocator's /// internal data structures. For example it is **not** safe @@ -673,6 +714,7 @@ impl<T, A: Allocator> Vec<T, A> { /// /// [`String`]: crate::string::String /// [`dealloc`]: crate::alloc::GlobalAlloc::dealloc + /// [*fit*]: crate::alloc::Allocator#memory-fitting /// /// # Examples /// @@ -711,6 +753,29 @@ impl<T, A: Allocator> Vec<T, A> { /// assert_eq!(rebuilt, [4, 5, 6]); /// } /// ``` + /// + /// Using memory that was allocated elsewhere: + /// + /// ```rust + /// use std::alloc::{alloc, Layout}; + /// + /// fn main() { + /// let layout = Layout::array::<u32>(16).expect("overflow cannot happen"); + /// let vec = unsafe { + /// let mem = alloc(layout).cast::<u32>(); + /// if mem.is_null() { + /// return; + /// } + /// + /// mem.write(1_000_000); + /// + /// Vec::from_raw_parts(mem, 1, 16) + /// }; + /// + /// assert_eq!(vec, &[1_000_000]); + /// assert_eq!(vec.capacity(), 16); + /// } + /// ``` #[inline] #[unstable(feature = "allocator_api", issue = "32838")] pub unsafe fn from_raw_parts_in(ptr: *mut T, length: usize, capacity: usize, alloc: A) -> Self { @@ -803,13 +868,14 @@ impl<T, A: Allocator> Vec<T, A> { (ptr, len, capacity, alloc) } - /// Returns the number of elements the vector can hold without + /// Returns the total number of elements the vector can hold without /// reallocating. /// /// # Examples /// /// ``` - /// let vec: Vec<i32> = Vec::with_capacity(10); + /// let mut vec: Vec<i32> = Vec::with_capacity(10); + /// vec.push(42); /// assert_eq!(vec.capacity(), 10); /// ``` #[inline] @@ -1774,6 +1840,51 @@ impl<T, A: Allocator> Vec<T, A> { } } + /// Appends an element if there is sufficient spare capacity, otherwise an error is returned + /// with the element. + /// + /// Unlike [`push`] this method will not reallocate when there's insufficient capacity. + /// The caller should use [`reserve`] or [`try_reserve`] to ensure that there is enough capacity. + /// + /// [`push`]: Vec::push + /// [`reserve`]: Vec::reserve + /// [`try_reserve`]: Vec::try_reserve + /// + /// # Examples + /// + /// A manual, panic-free alternative to [`FromIterator`]: + /// + /// ``` + /// #![feature(vec_push_within_capacity)] + /// + /// use std::collections::TryReserveError; + /// fn from_iter_fallible<T>(iter: impl Iterator<Item=T>) -> Result<Vec<T>, TryReserveError> { + /// let mut vec = Vec::new(); + /// for value in iter { + /// if let Err(value) = vec.push_within_capacity(value) { + /// vec.try_reserve(1)?; + /// // this cannot fail, the previous line either returned or added at least 1 free slot + /// let _ = vec.push_within_capacity(value); + /// } + /// } + /// Ok(vec) + /// } + /// assert_eq!(from_iter_fallible(0..100), Ok(Vec::from_iter(0..100))); + /// ``` + #[inline] + #[unstable(feature = "vec_push_within_capacity", issue = "100486")] + pub fn push_within_capacity(&mut self, value: T) -> Result<(), T> { + if self.len == self.buf.capacity() { + return Err(value); + } + unsafe { + let end = self.as_mut_ptr().add(self.len); + ptr::write(end, value); + self.len += 1; + } + Ok(()) + } + /// Removes the last element from a vector and returns it, or [`None`] if it /// is empty. /// @@ -1889,9 +2000,7 @@ impl<T, A: Allocator> Vec<T, A> { unsafe { // set self.vec length's to start, to be safe in case Drain is leaked self.set_len(start); - // Use the borrow in the IterMut to indicate borrowing behavior of the - // whole Drain iterator (like &mut T). - let range_slice = slice::from_raw_parts_mut(self.as_mut_ptr().add(start), end - start); + let range_slice = slice::from_raw_parts(self.as_ptr().add(start), end - start); Drain { tail_start: end, tail_len: len - end, @@ -2083,7 +2192,6 @@ impl<T, A: Allocator> Vec<T, A> { /// static_ref[0] += 1; /// assert_eq!(static_ref, &[2, 2, 3]); /// ``` - #[cfg(not(no_global_oom_handling))] #[stable(feature = "vec_leak", since = "1.47.0")] #[inline] pub fn leak<'a>(self) -> &'a mut [T] @@ -2347,7 +2455,7 @@ impl<T, A: Allocator, const N: usize> Vec<[T; N], A> { #[unstable(feature = "slice_flatten", issue = "95629")] pub fn into_flattened(self) -> Vec<T, A> { let (ptr, len, cap, alloc) = self.into_raw_parts_with_alloc(); - let (new_len, new_cap) = if mem::size_of::<T>() == 0 { + let (new_len, new_cap) = if T::IS_ZST { (len.checked_mul(N).expect("vec len overflow"), usize::MAX) } else { // SAFETY: @@ -2677,7 +2785,7 @@ impl<T, A: Allocator> IntoIterator for Vec<T, A> { let mut me = ManuallyDrop::new(self); let alloc = ManuallyDrop::new(ptr::read(me.allocator())); let begin = me.as_mut_ptr(); - let end = if mem::size_of::<T>() == 0 { + let end = if T::IS_ZST { begin.wrapping_byte_add(me.len()) } else { begin.add(me.len()) as *const T diff --git a/library/alloc/tests/autotraits.rs b/library/alloc/tests/autotraits.rs new file mode 100644 index 000000000..8ff5f0abe --- /dev/null +++ b/library/alloc/tests/autotraits.rs @@ -0,0 +1,293 @@ +fn require_sync<T: Sync>(_: T) {} +fn require_send_sync<T: Send + Sync>(_: T) {} + +struct NotSend(*const ()); +unsafe impl Sync for NotSend {} + +#[test] +fn test_btree_map() { + // Tests of this form are prone to https://github.com/rust-lang/rust/issues/64552. + // + // In theory the async block's future would be Send if the value we hold + // across the await point is Send, and Sync if the value we hold across the + // await point is Sync. + // + // We test autotraits in this convoluted way, instead of a straightforward + // `require_send_sync::<TypeIWantToTest>()`, because the interaction with + // generators exposes some current limitations in rustc's ability to prove a + // lifetime bound on the erased generator witness types. See the above link. + // + // A typical way this would surface in real code is: + // + // fn spawn<T: Future + Send>(_: T) {} + // + // async fn f() { + // let map = BTreeMap::<u32, Box<dyn Send + Sync>>::new(); + // for _ in &map { + // async {}.await; + // } + // } + // + // fn main() { + // spawn(f()); + // } + // + // where with some unintentionally overconstrained Send impls in liballoc's + // internals, the future might incorrectly not be Send even though every + // single type involved in the program is Send and Sync. + require_send_sync(async { + let _v = None::<alloc::collections::btree_map::Iter<'_, &u32, &u32>>; + async {}.await; + }); + + // Testing like this would not catch all issues that the above form catches. + require_send_sync(None::<alloc::collections::btree_map::Iter<'_, &u32, &u32>>); + + require_sync(async { + let _v = None::<alloc::collections::btree_map::Iter<'_, u32, NotSend>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_map::BTreeMap<&u32, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::< + alloc::collections::btree_map::DrainFilter< + '_, + &u32, + &u32, + fn(&&u32, &mut &u32) -> bool, + >, + >; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_map::Entry<'_, &u32, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_map::IntoIter<&u32, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_map::IntoKeys<&u32, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_map::IntoValues<&u32, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_map::Iter<'_, &u32, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_map::IterMut<'_, &u32, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_map::Keys<'_, &u32, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_map::OccupiedEntry<'_, &u32, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_map::OccupiedError<'_, &u32, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_map::Range<'_, &u32, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_map::RangeMut<'_, &u32, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_map::VacantEntry<'_, &u32, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_map::Values<'_, &u32, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_map::ValuesMut<'_, &u32, &u32>>; + async {}.await; + }); +} + +#[test] +fn test_btree_set() { + require_send_sync(async { + let _v = None::<alloc::collections::btree_set::BTreeSet<&u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_set::Difference<'_, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_set::DrainFilter<'_, &u32, fn(&&u32) -> bool>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_set::Intersection<'_, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_set::IntoIter<&u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_set::Iter<'_, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_set::Range<'_, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_set::SymmetricDifference<'_, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::btree_set::Union<'_, &u32>>; + async {}.await; + }); +} + +#[test] +fn test_binary_heap() { + require_send_sync(async { + let _v = None::<alloc::collections::binary_heap::BinaryHeap<&u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::binary_heap::Drain<'_, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::binary_heap::DrainSorted<'_, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::binary_heap::IntoIter<&u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::binary_heap::IntoIterSorted<&u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::binary_heap::Iter<'_, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::binary_heap::PeekMut<'_, &u32>>; + async {}.await; + }); +} + +#[test] +fn test_linked_list() { + require_send_sync(async { + let _v = None::<alloc::collections::linked_list::Cursor<'_, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::linked_list::CursorMut<'_, &u32>>; + async {}.await; + }); + + // FIXME + /* + require_send_sync(async { + let _v = + None::<alloc::collections::linked_list::DrainFilter<'_, &u32, fn(&mut &u32) -> bool>>; + async {}.await; + }); + */ + + require_send_sync(async { + let _v = None::<alloc::collections::linked_list::IntoIter<&u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::linked_list::Iter<'_, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::linked_list::IterMut<'_, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::linked_list::LinkedList<&u32>>; + async {}.await; + }); +} + +#[test] +fn test_vec_deque() { + require_send_sync(async { + let _v = None::<alloc::collections::vec_deque::Drain<'_, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::vec_deque::IntoIter<&u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::vec_deque::Iter<'_, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::vec_deque::IterMut<'_, &u32>>; + async {}.await; + }); + + require_send_sync(async { + let _v = None::<alloc::collections::vec_deque::VecDeque<&u32>>; + async {}.await; + }); +} diff --git a/library/alloc/tests/lib.rs b/library/alloc/tests/lib.rs index 490c0d8f7..ffc5ca7a5 100644 --- a/library/alloc/tests/lib.rs +++ b/library/alloc/tests/lib.rs @@ -2,6 +2,7 @@ #![feature(alloc_layout_extra)] #![feature(assert_matches)] #![feature(box_syntax)] +#![feature(btree_drain_filter)] #![feature(cow_is_borrowed)] #![feature(const_box)] #![feature(const_convert)] @@ -14,6 +15,8 @@ #![feature(core_intrinsics)] #![feature(drain_filter)] #![feature(exact_size_is_empty)] +#![feature(linked_list_cursors)] +#![feature(map_try_insert)] #![feature(new_uninit)] #![feature(pattern)] #![feature(trusted_len)] @@ -32,7 +35,7 @@ #![feature(slice_group_by)] #![feature(slice_partition_dedup)] #![feature(string_remove_matches)] -#![feature(const_btree_new)] +#![feature(const_btree_len)] #![feature(const_default_impls)] #![feature(const_trait_impl)] #![feature(const_str_from_utf8)] @@ -41,7 +44,6 @@ #![feature(pointer_is_aligned)] #![feature(slice_flatten)] #![feature(thin_box)] -#![feature(bench_black_box)] #![feature(strict_provenance)] #![feature(once_cell)] #![feature(drain_keep_rest)] @@ -50,6 +52,7 @@ use std::collections::hash_map::DefaultHasher; use std::hash::{Hash, Hasher}; mod arc; +mod autotraits; mod borrow; mod boxed; mod btree_set_hash; diff --git a/library/alloc/tests/vec.rs b/library/alloc/tests/vec.rs index f140fc414..e02711870 100644 --- a/library/alloc/tests/vec.rs +++ b/library/alloc/tests/vec.rs @@ -1191,48 +1191,53 @@ fn test_from_iter_specialization_panic_during_iteration_drops() { } #[test] -fn test_from_iter_specialization_panic_during_drop_leaks() { - static mut DROP_COUNTER: usize = 0; +fn test_from_iter_specialization_panic_during_drop_doesnt_leak() { + static mut DROP_COUNTER_OLD: [usize; 5] = [0; 5]; + static mut DROP_COUNTER_NEW: [usize; 2] = [0; 2]; #[derive(Debug)] - enum Droppable { - DroppedTwice(Box<i32>), - PanicOnDrop, - } + struct Old(usize); - impl Drop for Droppable { + impl Drop for Old { fn drop(&mut self) { - match self { - Droppable::DroppedTwice(_) => { - unsafe { - DROP_COUNTER += 1; - } - println!("Dropping!") - } - Droppable::PanicOnDrop => { - if !std::thread::panicking() { - panic!(); - } - } + unsafe { + DROP_COUNTER_OLD[self.0] += 1; + } + + if self.0 == 3 { + panic!(); } + + println!("Dropped Old: {}", self.0); } } - let mut to_free: *mut Droppable = core::ptr::null_mut(); - let mut cap = 0; + #[derive(Debug)] + struct New(usize); + + impl Drop for New { + fn drop(&mut self) { + unsafe { + DROP_COUNTER_NEW[self.0] += 1; + } + + println!("Dropped New: {}", self.0); + } + } let _ = std::panic::catch_unwind(AssertUnwindSafe(|| { - let mut v = vec![Droppable::DroppedTwice(Box::new(123)), Droppable::PanicOnDrop]; - to_free = v.as_mut_ptr(); - cap = v.capacity(); - let _ = v.into_iter().take(0).collect::<Vec<_>>(); + let v = vec![Old(0), Old(1), Old(2), Old(3), Old(4)]; + let _ = v.into_iter().map(|x| New(x.0)).take(2).collect::<Vec<_>>(); })); - assert_eq!(unsafe { DROP_COUNTER }, 1); - // clean up the leak to keep miri happy - unsafe { - drop(Vec::from_raw_parts(to_free, 0, cap)); - } + assert_eq!(unsafe { DROP_COUNTER_OLD[0] }, 1); + assert_eq!(unsafe { DROP_COUNTER_OLD[1] }, 1); + assert_eq!(unsafe { DROP_COUNTER_OLD[2] }, 1); + assert_eq!(unsafe { DROP_COUNTER_OLD[3] }, 1); + assert_eq!(unsafe { DROP_COUNTER_OLD[4] }, 1); + + assert_eq!(unsafe { DROP_COUNTER_NEW[0] }, 1); + assert_eq!(unsafe { DROP_COUNTER_NEW[1] }, 1); } // regression test for issue #85322. Peekable previously implemented InPlaceIterable, |