Rollup of 11 pull requests

README.md

@@ -243,6 +243,8 @@ The Rust community congregates in a few places:
 If you are interested in contributing to the Rust project, please take a look
 at the [Getting Started][gettingstarted] guide in the [rustc-dev-guide].
 
+[rustc-dev-guide]: https://rustc-dev-guide.rust-lang.org
+
 ## License
 
 Rust is primarily distributed under the terms of both the MIT license

compiler/rustc_ast/src/token.rs

@@ -173,6 +173,7 @@ pub fn ident_can_begin_expr(name: Symbol, span: Span, is_raw: bool) -> bool {
             kw::Move,
             kw::Return,
             kw::True,
+            kw::Try,
             kw::Unsafe,
             kw::While,
             kw::Yield,
@@ -809,9 +810,19 @@ impl Nonterminal {
             if let ExpnKind::Macro(_, macro_name) = orig_span.ctxt().outer_expn_data().kind {
                 let filename = source_map.span_to_filename(orig_span);
                 if let FileName::Real(RealFileName::Named(path)) = filename {
-                    if (path.ends_with("time-macros-impl/src/lib.rs")
-                        && macro_name == sym::impl_macros)
-                        || (path.ends_with("js-sys/src/lib.rs") && macro_name == sym::arrays)
+                    let matches_prefix = |prefix| {
+                        // Check for a path that ends with 'prefix*/src/lib.rs'
+                        let mut iter = path.components().rev();
+                        iter.next().and_then(|p| p.as_os_str().to_str()) == Some("lib.rs")
+                            && iter.next().and_then(|p| p.as_os_str().to_str()) == Some("src")
+                            && iter
+                                .next()
+                                .and_then(|p| p.as_os_str().to_str())
+                                .map_or(false, |p| p.starts_with(prefix))
+                    };
+
+                    if (macro_name == sym::impl_macros && matches_prefix("time-macros-impl"))
+                        || (macro_name == sym::arrays && matches_prefix("js-sys"))
                     {
                         let snippet = source_map.span_to_snippet(orig_span);
                         if snippet.as_deref() == Ok("$name") {

compiler/rustc_target/src/spec/wasm32_base.rs

@@ -83,6 +83,7 @@ pub fn options() -> TargetOptions {
         dll_prefix: String::new(),
         dll_suffix: ".wasm".to_string(),
         linker_is_gnu: false,
+        eh_frame_header: false,
 
         max_atomic_width: Some(64),
 

library/alloc/tests/vec.rs

@@ -74,6 +74,42 @@ fn test_zst_capacity() {
     assert_eq!(Vec::<()>::new().capacity(), usize::MAX);
 }
 
+#[test]
+fn test_indexing() {
+    let v: Vec<isize> = vec![10, 20];
+    assert_eq!(v[0], 10);
+    assert_eq!(v[1], 20);
+    let mut x: usize = 0;
+    assert_eq!(v[x], 10);
+    assert_eq!(v[x + 1], 20);
+    x = x + 1;
+    assert_eq!(v[x], 20);
+    assert_eq!(v[x - 1], 10);
+}
+
+#[test]
+fn test_debug_fmt() {
+    let vec1: Vec<isize> = vec![];
+    assert_eq!("[]", format!("{:?}", vec1));
+
+    let vec2 = vec![0, 1];
+    assert_eq!("[0, 1]", format!("{:?}", vec2));
+
+    let slice: &[isize] = &[4, 5];
+    assert_eq!("[4, 5]", format!("{:?}", slice));
+}
+
+#[test]
+fn test_push() {
+    let mut v = vec![];
+    v.push(1);
+    assert_eq!(v, [1]);
+    v.push(2);
+    assert_eq!(v, [1, 2]);
+    v.push(3);
+    assert_eq!(v, [1, 2, 3]);
+}
+
 #[test]
 fn test_extend() {
     let mut v = Vec::new();
@@ -119,6 +155,18 @@ fn test_extend() {
     assert_eq!(count_x, 1);
 }
 
+#[test]
+fn test_extend_from_slice() {
+    let a: Vec<isize> = vec![1, 2, 3, 4, 5];
+    let b: Vec<isize> = vec![6, 7, 8, 9, 0];
+
+    let mut v: Vec<isize> = a;
+
+    v.extend_from_slice(&b);
+
+    assert_eq!(v, [1, 2, 3, 4, 5, 6, 7, 8, 9, 0]);
+}
+
 #[test]
 fn test_extend_ref() {
     let mut v = vec![1, 2];
@@ -134,6 +182,14 @@ fn test_extend_ref() {
     assert_eq!(v, [1, 2, 3, 4, 5, 6, 7]);
 }
 
+#[test]
+fn test_slice_from_ref() {
+    let values = vec![1, 2, 3, 4, 5];
+    let slice = &values[1..3];
+
+    assert_eq!(slice, [2, 3]);
+}
+
 #[test]
 fn test_slice_from_mut() {
     let mut values = vec![1, 2, 3, 4, 5];

library/core/src/intrinsics.rs

@@ -831,7 +831,7 @@ extern "rust-intrinsic" {
     /// Gets a reference to a static `Location` indicating where it was called.
     ///
     /// Consider using [`crate::panic::Location::caller`] instead.
-    #[rustc_const_unstable(feature = "const_caller_location", issue = "47809")]
+    #[rustc_const_unstable(feature = "const_caller_location", issue = "76156")]
     pub fn caller_location() -> &'static crate::panic::Location<'static>;
 
     /// Moves a value out of scope without running drop glue.

library/core/src/iter/traits/iterator.rs

@@ -648,11 +648,9 @@ pub trait Iterator {
     /// Creates an iterator which uses a closure to determine if an element
     /// should be yielded.
     ///
-    /// The closure must return `true` or `false`. `filter()` creates an
-    /// iterator which calls this closure on each element. If the closure
-    /// returns `true`, then the element is returned. If the closure returns
-    /// `false`, it will try again, and call the closure on the next element,
-    /// seeing if it passes the test.
+    /// Given an element the closure must return `true` or `false`. The returned
+    /// iterator will yield only the elements for which the closure returns
+    /// true.
     ///
     /// # Examples
     ///
@@ -719,24 +717,16 @@ pub trait Iterator {
 
     /// Creates an iterator that both filters and maps.
     ///
-    /// The closure must return an [`Option<T>`]. `filter_map` creates an
-    /// iterator which calls this closure on each element. If the closure
-    /// returns [`Some(element)`][`Some`], then that element is returned. If the
-    /// closure returns [`None`], it will try again, and call the closure on the
-    /// next element, seeing if it will return [`Some`].
+    /// The returned iterator yields only the `value`s for which the supplied
+    /// closure returns `Some(value)`.
     ///
-    /// Why `filter_map` and not just [`filter`] and [`map`]? The key is in this
-    /// part:
+    /// `filter_map` can be used to make chains of [`filter`] and [`map`] more
+    /// concise. The example below shows how a `map().filter().map()` can be
+    /// shortened to a single call to `filter_map`.
     ///
     /// [`filter`]: Iterator::filter
     /// [`map`]: Iterator::map
     ///
-    /// > If the closure returns [`Some(element)`][`Some`], then that element is returned.
-    ///
-    /// In other words, it removes the [`Option<T>`] layer automatically. If your
-    /// mapping is already returning an [`Option<T>`] and you want to skip over
-    /// [`None`]s, then `filter_map` is much, much nicer to use.
-    ///
     /// # Examples
     ///
     /// Basic usage:

library/core/src/panic.rs

@@ -225,7 +225,7 @@ impl<'a> Location<'a> {
     /// assert_ne!(this_location.column(), another_location.column());
     /// ```
     #[stable(feature = "track_caller", since = "1.46.0")]
-    #[rustc_const_unstable(feature = "const_caller_location", issue = "47809")]
+    #[rustc_const_unstable(feature = "const_caller_location", issue = "76156")]
     #[track_caller]
     pub const fn caller() -> &'static Location<'static> {
         crate::intrinsics::caller_location()

library/core/src/pin.rs

@@ -541,7 +541,7 @@ impl<P: Deref> Pin<P> {
     /// use std::pin::Pin;
     ///
     /// fn move_pinned_rc<T>(mut x: Rc<T>) {
-    ///     let pinned = unsafe { Pin::new_unchecked(x.clone()) };
+    ///     let pinned = unsafe { Pin::new_unchecked(Rc::clone(&x)) };
     ///     {
     ///         let p: Pin<&T> = pinned.as_ref();
     ///         // This should mean the pointee can never move again.

library/core/src/sync/atomic.rs

@@ -76,7 +76,7 @@
 //! fn main() {
 //!     let spinlock = Arc::new(AtomicUsize::new(1));
 //!
-//!     let spinlock_clone = spinlock.clone();
+//!     let spinlock_clone = Arc::clone(&spinlock);
 //!     let thread = thread::spawn(move|| {
 //!         spinlock_clone.store(0, Ordering::SeqCst);
 //!     });

library/std/src/collections/hash/map.rs

@@ -2382,15 +2382,15 @@ impl<'a, K, V> OccupiedEntry<'a, K, V> {
     /// use std::rc::Rc;
     ///
     /// let mut map: HashMap<Rc<String>, u32> = HashMap::new();
-    /// let mut known_strings: Vec<Rc<String>> = Vec::new();
+    /// let known_strings: Vec<Rc<String>> = Vec::new();
     ///
     /// // Initialise known strings, run program, etc.
     ///
     /// reclaim_memory(&mut map, &known_strings);
     ///
     /// fn reclaim_memory(map: &mut HashMap<Rc<String>, u32>, known_strings: &[Rc<String>] ) {
     ///     for s in known_strings {
-    ///         if let Entry::Occupied(entry) = map.entry(s.clone()) {
+    ///         if let Entry::Occupied(entry) = map.entry(Rc::clone(s)) {
     ///             // Replaces the entry's key with our version of it in `known_strings`.
     ///             entry.replace_key();
     ///         }

library/std/src/lazy.rs

@@ -6,6 +6,7 @@ mod tests;
 use crate::{
     cell::{Cell, UnsafeCell},
     fmt,
+    marker::PhantomData,
     mem::{self, MaybeUninit},
     ops::{Deref, Drop},
     panic::{RefUnwindSafe, UnwindSafe},
@@ -46,6 +47,26 @@ pub struct SyncOnceCell<T> {
     once: Once,
     // Whether or not the value is initialized is tracked by `state_and_queue`.
     value: UnsafeCell<MaybeUninit<T>>,
+    /// `PhantomData` to make sure dropck understands we're dropping T in our Drop impl.
+    ///
+    /// ```compile_fail,E0597
+    /// #![feature(once_cell)]
+    ///
+    /// use std::lazy::SyncOnceCell;
+    ///
+    /// struct A<'a>(&'a str);
+    ///
+    /// impl<'a> Drop for A<'a> {
+    ///     fn drop(&mut self) {}
+    /// }
+    ///
+    /// let cell = SyncOnceCell::new();
+    /// {
+    ///     let s = String::new();
+    ///     let _ = cell.set(A(&s));
+    /// }
+    /// ```
+    _marker: PhantomData<T>,
 }
 
 // Why do we need `T: Send`?
@@ -119,7 +140,11 @@ impl<T> SyncOnceCell<T> {
     /// Creates a new empty cell.
     #[unstable(feature = "once_cell", issue = "74465")]
     pub const fn new() -> SyncOnceCell<T> {
-        SyncOnceCell { once: Once::new(), value: UnsafeCell::new(MaybeUninit::uninit()) }
+        SyncOnceCell {
+            once: Once::new(),
+            value: UnsafeCell::new(MaybeUninit::uninit()),
+            _marker: PhantomData,
+        }
     }
 
     /// Gets the reference to the underlying value.

library/std/src/sync/barrier.rs

@@ -16,7 +16,7 @@ use crate::sync::{Condvar, Mutex};
 /// let mut handles = Vec::with_capacity(10);
 /// let barrier = Arc::new(Barrier::new(10));
 /// for _ in 0..10 {
-///     let c = barrier.clone();
+///     let c = Arc::clone(&barrier);
 ///     // The same messages will be printed together.
 ///     // You will NOT see any interleaving.
 ///     handles.push(thread::spawn(move|| {
@@ -113,7 +113,7 @@ impl Barrier {
     /// let mut handles = Vec::with_capacity(10);
     /// let barrier = Arc::new(Barrier::new(10));
     /// for _ in 0..10 {
-    ///     let c = barrier.clone();
+    ///     let c = Arc::clone(&barrier);
     ///     // The same messages will be printed together.
     ///     // You will NOT see any interleaving.
     ///     handles.push(thread::spawn(move|| {

library/std/src/sync/condvar.rs

@@ -36,7 +36,7 @@ impl WaitTimeoutResult {
     /// use std::time::Duration;
     ///
     /// let pair = Arc::new((Mutex::new(false), Condvar::new()));
-    /// let pair2 = pair.clone();
+    /// let pair2 = Arc::clone(&pair);
     ///
     /// thread::spawn(move || {
     ///     let (lock, cvar) = &*pair2;
@@ -93,7 +93,7 @@ impl WaitTimeoutResult {
 /// use std::thread;
 ///
 /// let pair = Arc::new((Mutex::new(false), Condvar::new()));
-/// let pair2 = pair.clone();
+/// let pair2 = Arc::clone(&pair);
 ///
 /// // Inside of our lock, spawn a new thread, and then wait for it to start.
 /// thread::spawn(move|| {
@@ -176,7 +176,7 @@ impl Condvar {
     /// use std::thread;
     ///
     /// let pair = Arc::new((Mutex::new(false), Condvar::new()));
-    /// let pair2 = pair.clone();
+    /// let pair2 = Arc::clone(&pair);
     ///
     /// thread::spawn(move|| {
     ///     let (lock, cvar) = &*pair2;
@@ -232,7 +232,7 @@ impl Condvar {
     /// use std::thread;
     ///
     /// let pair = Arc::new((Mutex::new(true), Condvar::new()));
-    /// let pair2 = pair.clone();
+    /// let pair2 = Arc::clone(&pair);
     ///
     /// thread::spawn(move|| {
     ///     let (lock, cvar) = &*pair2;
@@ -291,7 +291,7 @@ impl Condvar {
     /// use std::thread;
     ///
     /// let pair = Arc::new((Mutex::new(false), Condvar::new()));
-    /// let pair2 = pair.clone();
+    /// let pair2 = Arc::clone(&pair);
     ///
     /// thread::spawn(move|| {
     ///     let (lock, cvar) = &*pair2;
@@ -363,7 +363,7 @@ impl Condvar {
     /// use std::time::Duration;
     ///
     /// let pair = Arc::new((Mutex::new(false), Condvar::new()));
-    /// let pair2 = pair.clone();
+    /// let pair2 = Arc::clone(&pair);
     ///
     /// thread::spawn(move|| {
     ///     let (lock, cvar) = &*pair2;
@@ -432,7 +432,7 @@ impl Condvar {
     /// use std::time::Duration;
     ///
     /// let pair = Arc::new((Mutex::new(true), Condvar::new()));
-    /// let pair2 = pair.clone();
+    /// let pair2 = Arc::clone(&pair);
     ///
     /// thread::spawn(move|| {
     ///     let (lock, cvar) = &*pair2;
@@ -496,7 +496,7 @@ impl Condvar {
     /// use std::thread;
     ///
     /// let pair = Arc::new((Mutex::new(false), Condvar::new()));
-    /// let pair2 = pair.clone();
+    /// let pair2 = Arc::clone(&pair);
     ///
     /// thread::spawn(move|| {
     ///     let (lock, cvar) = &*pair2;
@@ -536,7 +536,7 @@ impl Condvar {
     /// use std::thread;
     ///
     /// let pair = Arc::new((Mutex::new(false), Condvar::new()));
-    /// let pair2 = pair.clone();
+    /// let pair2 = Arc::clone(&pair);
     ///
     /// thread::spawn(move|| {
     ///     let (lock, cvar) = &*pair2;