Merge from rustc

Author: RalfJung

alloc/src/collections/binary_heap/mod.rs

@@ -1216,7 +1216,6 @@ impl<T, A: Allocator> BinaryHeap<T, A> {
     /// Basic usage:
     ///
     /// ```
-    /// #![feature(binary_heap_as_slice)]
     /// use std::collections::BinaryHeap;
     /// use std::io::{self, Write};
     ///
@@ -1225,7 +1224,7 @@ impl<T, A: Allocator> BinaryHeap<T, A> {
     /// io::sink().write(heap.as_slice()).unwrap();
     /// ```
     #[must_use]
-    #[unstable(feature = "binary_heap_as_slice", issue = "83659")]
+    #[stable(feature = "binary_heap_as_slice", since = "CURRENT_RUSTC_VERSION")]
     pub fn as_slice(&self) -> &[T] {
         self.data.as_slice()
     }

alloc/src/lib.rs

@@ -121,7 +121,6 @@
 #![feature(deref_pure_trait)]
 #![feature(dispatch_from_dyn)]
 #![feature(error_generic_member_access)]
-#![feature(error_in_core)]
 #![feature(exact_size_is_empty)]
 #![feature(extend_one)]
 #![feature(fmt_internals)]

alloc/tests/lib.rs

@@ -24,7 +24,6 @@
 #![feature(binary_heap_into_iter_sorted)]
 #![feature(binary_heap_drain_sorted)]
 #![feature(slice_ptr_get)]
-#![feature(binary_heap_as_slice)]
 #![feature(inplace_iteration)]
 #![feature(iter_advance_by)]
 #![feature(iter_next_chunk)]

backtrace

@@ -1 +1 @@
-Subproject commit 5e05efa87905fb5b351a2bc5644d60c57d6d9327
+Subproject commit 72265bea210891ae47bbe6d4f17b493ef0606619

core/src/error.rs

@@ -1,5 +1,5 @@
 #![doc = include_str!("error.md")]
-#![unstable(feature = "error_in_core", issue = "103765")]
+#![stable(feature = "error_in_core", since = "CURRENT_RUSTC_VERSION")]
 
 #[cfg(test)]
 mod tests;
@@ -130,7 +130,6 @@ pub trait Error: Debug + Display {
     ///
     /// ```rust
     /// #![feature(error_generic_member_access)]
-    /// #![feature(error_in_core)]
     /// use core::fmt;
     /// use core::error::{request_ref, Request};
     ///
@@ -361,8 +360,7 @@ impl dyn Error {
 /// Get a string value from an error.
 ///
 /// ```rust
-/// # #![feature(error_generic_member_access)]
-/// # #![feature(error_in_core)]
+/// #![feature(error_generic_member_access)]
 /// use std::error::Error;
 /// use core::error::request_value;
 ///
@@ -385,8 +383,7 @@ where
 /// Get a string reference from an error.
 ///
 /// ```rust
-/// # #![feature(error_generic_member_access)]
-/// # #![feature(error_in_core)]
+/// #![feature(error_generic_member_access)]
 /// use core::error::Error;
 /// use core::error::request_ref;
 ///
@@ -458,7 +455,6 @@ where
 ///
 /// ```
 /// #![feature(error_generic_member_access)]
-/// #![feature(error_in_core)]
 /// use core::fmt;
 /// use core::error::Request;
 /// use core::error::request_ref;
@@ -529,7 +525,6 @@ impl<'a> Request<'a> {
     ///
     /// ```rust
     /// #![feature(error_generic_member_access)]
-    /// #![feature(error_in_core)]
     ///
     /// use core::error::Request;
     ///
@@ -564,7 +559,6 @@ impl<'a> Request<'a> {
     ///
     /// ```rust
     /// #![feature(error_generic_member_access)]
-    /// #![feature(error_in_core)]
     ///
     /// use core::error::Request;
     ///
@@ -600,7 +594,6 @@ impl<'a> Request<'a> {
     ///
     /// ```rust
     /// #![feature(error_generic_member_access)]
-    /// #![feature(error_in_core)]
     ///
     /// use core::error::Request;
     ///
@@ -633,7 +626,6 @@ impl<'a> Request<'a> {
     ///
     /// ```rust
     /// #![feature(error_generic_member_access)]
-    /// #![feature(error_in_core)]
     ///
     /// use core::error::Request;
     ///
@@ -700,7 +692,6 @@ impl<'a> Request<'a> {
     ///
     /// ```rust
     /// #![feature(error_generic_member_access)]
-    /// #![feature(error_in_core)]
     ///
     /// use core::error::Request;
     /// use core::error::request_value;
@@ -788,7 +779,6 @@ impl<'a> Request<'a> {
     ///
     /// ```rust
     /// #![feature(error_generic_member_access)]
-    /// #![feature(error_in_core)]
     ///
     /// use core::error::Request;
     /// use core::error::request_ref;

core/src/fmt/num.rs

@@ -212,6 +212,7 @@ static DEC_DIGITS_LUT: &[u8; 200] = b"0001020304050607080910111213141516171819\
 
 macro_rules! impl_Display {
     ($($t:ident),* as $u:ident via $conv_fn:ident named $name:ident) => {
+        #[cfg(not(feature = "optimize_for_size"))]
         fn $name(mut n: $u, is_nonnegative: bool, f: &mut fmt::Formatter<'_>) -> fmt::Result {
             // 2^128 is about 3*10^38, so 39 gives an extra byte of space
             let mut buf = [MaybeUninit::<u8>::uninit(); 39];
@@ -277,6 +278,38 @@ macro_rules! impl_Display {
             f.pad_integral(is_nonnegative, "", buf_slice)
         }
 
+        #[cfg(feature = "optimize_for_size")]
+        fn $name(mut n: $u, is_nonnegative: bool, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+            // 2^128 is about 3*10^38, so 39 gives an extra byte of space
+            let mut buf = [MaybeUninit::<u8>::uninit(); 39];
+            let mut curr = buf.len();
+            let buf_ptr = MaybeUninit::slice_as_mut_ptr(&mut buf);
+
+            // SAFETY: To show that it's OK to copy into `buf_ptr`, notice that at the beginning
+            // `curr == buf.len() == 39 > log(n)` since `n < 2^128 < 10^39`, and at
+            // each step this is kept the same as `n` is divided. Since `n` is always
+            // non-negative, this means that `curr > 0` so `buf_ptr[curr..curr + 1]`
+            // is safe to access.
+            unsafe {
+                loop {
+                    curr -= 1;
+                    buf_ptr.add(curr).write((n % 10) as u8 + b'0');
+                    n /= 10;
+
+                    if n == 0 {
+                        break;
+                    }
+                }
+            }
+
+            // SAFETY: `curr` > 0 (since we made `buf` large enough), and all the chars are valid UTF-8
+            let buf_slice = unsafe {
+                str::from_utf8_unchecked(
+                    slice::from_raw_parts(buf_ptr.add(curr), buf.len() - curr))
+            };
+            f.pad_integral(is_nonnegative, "", buf_slice)
+        }
+
         $(#[stable(feature = "rust1", since = "1.0.0")]
         impl fmt::Display for $t {
             #[allow(unused_comparisons)]

core/src/option.rs

@@ -1708,8 +1708,6 @@ impl<T> Option<T> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(option_take_if)]
-    ///
     /// let mut x = Some(42);
     ///
     /// let prev = x.take_if(|v| if *v == 42 {
@@ -1726,7 +1724,7 @@ impl<T> Option<T> {
     /// assert_eq!(prev, Some(43));
     /// ```
     #[inline]
-    #[unstable(feature = "option_take_if", issue = "98934")]
+    #[stable(feature = "option_take_if", since = "CURRENT_RUSTC_VERSION")]
     pub fn take_if<P>(&mut self, predicate: P) -> Option<T>
     where
         P: FnOnce(&mut T) -> bool,

core/src/pin.rs

@@ -184,7 +184,7 @@
 //! requires at least a level of pointer indirection each time a new object is added to the mix
 //! (and, practically, a heap allocation).
 //!
-//! Although there were other reason as well, this issue of expensive composition is the key thing
+//! Although there were other reasons as well, this issue of expensive composition is the key thing
 //! that drove Rust towards adopting a different model. It is particularly a problem
 //! when one considers, for example, the implications of composing together the [`Future`]s which
 //! will eventually make up an asynchronous task (including address-sensitive `async fn` state

core/tests/lib.rs

@@ -112,7 +112,6 @@
 #![feature(const_slice_from_ref)]
 #![feature(waker_getters)]
 #![feature(error_generic_member_access)]
-#![feature(error_in_core)]
 #![feature(trait_upcasting)]
 #![feature(is_ascii_octdigit)]
 #![feature(get_many_mut)]

std/Cargo.toml

@@ -34,10 +34,10 @@ addr2line = { version = "0.22.0", optional = true, default-features = false }
 libc = { version = "0.2.153", default-features = false, features = ['rustc-dep-of-std'], public = true }
 
 [target.'cfg(all(not(target_os = "aix"), not(all(windows, target_env = "msvc", not(target_vendor = "uwp")))))'.dependencies]
-object = { version = "0.32.0", default-features = false, optional = true, features = ['read_core', 'elf', 'macho', 'pe', 'unaligned', 'archive'] }
+object = { version = "0.36.0", default-features = false, optional = true, features = ['read_core', 'elf', 'macho', 'pe', 'unaligned', 'archive'] }
 
 [target.'cfg(target_os = "aix")'.dependencies]
-object = { version = "0.32.0", default-features = false, optional = true, features = ['read_core', 'xcoff', 'unaligned', 'archive'] }
+object = { version = "0.36.0", default-features = false, optional = true, features = ['read_core', 'xcoff', 'unaligned', 'archive'] }
 
 [dev-dependencies]
 rand = { version = "0.8.5", default-features = false, features = ["alloc"] }

std/src/ffi/os_str.rs

@@ -533,6 +533,25 @@ impl OsString {
         unsafe { Box::from_raw(rw) }
     }
 
+    /// Consumes and leaks the `OsString`, returning a mutable reference to the contents,
+    /// `&'a mut OsStr`.
+    ///
+    /// The caller has free choice over the returned lifetime, including 'static.
+    /// Indeed, this function is ideally used for data that lives for the remainder of
+    /// the program’s life, as dropping the returned reference will cause a memory leak.
+    ///
+    /// It does not reallocate or shrink the `OsString`, so the leaked allocation may include
+    /// unused capacity that is not part of the returned slice. If you want to discard excess
+    /// capacity, call [`into_boxed_os_str`], and then [`Box::leak`] instead.
+    /// However, keep in mind that trimming the capacity may result in a reallocation and copy.
+    ///
+    /// [`into_boxed_os_str`]: Self::into_boxed_os_str
+    #[unstable(feature = "os_string_pathbuf_leak", issue = "125965")]
+    #[inline]
+    pub fn leak<'a>(self) -> &'a mut OsStr {
+        OsStr::from_inner_mut(self.inner.leak())
+    }
+
     /// Part of a hack to make PathBuf::push/pop more efficient.
     #[inline]
     pub(crate) fn as_mut_vec_for_path_buf(&mut self) -> &mut Vec<u8> {

std/src/ffi/os_str/tests.rs

@@ -23,6 +23,15 @@ fn test_os_string_clear() {
     assert_eq!(0, os_string.inner.as_inner().len());
 }
 
+#[test]
+fn test_os_string_leak() {
+    let os_string = OsString::from("have a cake");
+    let (len, cap) = (os_string.len(), os_string.capacity());
+    let leaked = os_string.leak();
+    assert_eq!(leaked.as_encoded_bytes(), b"have a cake");
+    unsafe { drop(String::from_raw_parts(leaked as *mut OsStr as _, len, cap)) }
+}
+
 #[test]
 fn test_os_string_capacity() {
     let os_string = OsString::with_capacity(0);

std/src/lib.rs

@@ -324,7 +324,6 @@
 #![feature(core_io_borrowed_buf)]
 #![feature(duration_constants)]
 #![feature(error_generic_member_access)]
-#![feature(error_in_core)]
 #![feature(error_iter)]
 #![feature(exact_size_is_empty)]
 #![feature(exclusive_wrapper)]

std/src/path.rs

@@ -1226,6 +1226,25 @@ impl PathBuf {
         self
     }
 
+    /// Consumes and leaks the `PathBuf`, returning a mutable reference to the contents,
+    /// `&'a mut Path`.
+    ///
+    /// The caller has free choice over the returned lifetime, including 'static.
+    /// Indeed, this function is ideally used for data that lives for the remainder of
+    /// the program’s life, as dropping the returned reference will cause a memory leak.
+    ///
+    /// It does not reallocate or shrink the `PathBuf`, so the leaked allocation may include
+    /// unused capacity that is not part of the returned slice. If you want to discard excess
+    /// capacity, call [`into_boxed_path`], and then [`Box::leak`] instead.
+    /// However, keep in mind that trimming the capacity may result in a reallocation and copy.
+    ///
+    /// [`into_boxed_path`]: Self::into_boxed_path
+    #[unstable(feature = "os_string_pathbuf_leak", issue = "125965")]
+    #[inline]
+    pub fn leak<'a>(self) -> &'a mut Path {
+        Path::from_inner_mut(self.inner.leak())
+    }
+
     /// Extends `self` with `path`.
     ///
     /// If `path` is absolute, it replaces the current path.

std/src/path/tests.rs

@@ -126,6 +126,16 @@ fn into() {
     assert_eq!(static_cow_path, owned_cow_path);
 }
 
+#[test]
+fn test_pathbuf_leak() {
+    let string = "/have/a/cake".to_owned();
+    let (len, cap) = (string.len(), string.capacity());
+    let buf = PathBuf::from(string);
+    let leaked = buf.leak();
+    assert_eq!(leaked.as_os_str().as_encoded_bytes(), b"/have/a/cake");
+    unsafe { drop(String::from_raw_parts(leaked.as_mut_os_str() as *mut OsStr as _, len, cap)) }
+}
+
 #[test]
 #[cfg(unix)]
 pub fn test_decompositions_unix() {

std/src/sys/os_str/bytes.rs

@@ -176,6 +176,11 @@ impl Buf {
         self.inner.extend_from_slice(&s.inner)
     }
 
+    #[inline]
+    pub fn leak<'a>(self) -> &'a mut Slice {
+        unsafe { mem::transmute(self.inner.leak()) }
+    }
+
     #[inline]
     pub fn into_box(self) -> Box<Slice> {
         unsafe { mem::transmute(self.inner.into_boxed_slice()) }

std/src/sys/os_str/wtf8.rs

@@ -138,6 +138,11 @@ impl Buf {
         self.inner.shrink_to(min_capacity)
     }
 
+    #[inline]
+    pub fn leak<'a>(self) -> &'a mut Slice {
+        unsafe { mem::transmute(self.inner.leak()) }
+    }
+
     #[inline]
     pub fn into_box(self) -> Box<Slice> {
         unsafe { mem::transmute(self.inner.into_box()) }

std/src/sys/pal/windows/c/README.md

@@ -3,7 +3,7 @@ be edited manually.
 
 To add bindings, edit `bindings.txt` then regenerate using the following command:
 
-    ./x run generate-windows-sys && ./x fmt library/std
+    ./x run generate-windows-sys && ./x fmt
 
 If you need to override generated functions or types then add them to
 `library/std/src/sys/pal/windows/c.rs`.

std/src/sys_common/wtf8.rs

@@ -325,6 +325,11 @@ impl Wtf8Buf {
         self.bytes.shrink_to(min_capacity)
     }
 
+    #[inline]
+    pub fn leak<'a>(self) -> &'a mut Wtf8 {
+        unsafe { Wtf8::from_mut_bytes_unchecked(self.bytes.leak()) }
+    }
+
     /// Returns the number of bytes that this string buffer can hold without reallocating.
     #[inline]
     pub fn capacity(&self) -> usize {