Merge pull request #20268 from lnicola/sync-from-rust

minor: Sync from downstream

9 files changed, 102 insertions, 125 deletions

diff --git a/library/std/src/io/mod.rs b/library/std/src/io/mod.rs
index 17c32d7a571..d351ee5e739 100644
--- a/library/std/src/io/mod.rs
+++ b/library/std/src/io/mod.rs
@@ -489,7 +489,7 @@ pub(crate) fn default_read_to_end<R: Read + ?Sized>(
             }
         };
 
-        let unfilled_but_initialized = cursor.init_ref().len();
+        let unfilled_but_initialized = cursor.init_mut().len();
         let bytes_read = cursor.written();
         let was_fully_initialized = read_buf.init_len() == buf_len;
 
@@ -3053,7 +3053,7 @@ impl<T: Read> Read for Take<T> {
             // The condition above guarantees that `self.limit` fits in `usize`.
             let limit = self.limit as usize;
 
-            let extra_init = cmp::min(limit, buf.init_ref().len());
+            let extra_init = cmp::min(limit, buf.init_mut().len());
 
             // SAFETY: no uninit data is written to ibuf
             let ibuf = unsafe { &mut buf.as_mut()[..limit] };
@@ -3068,7 +3068,7 @@ impl<T: Read> Read for Take<T> {
             let mut cursor = sliced_buf.unfilled();
             let result = self.inner.read_buf(cursor.reborrow());
 
-            let new_init = cursor.init_ref().len();
+            let new_init = cursor.init_mut().len();
             let filled = sliced_buf.len();
 
             // cursor / sliced_buf / ibuf must drop here
diff --git a/library/std/src/lib.rs b/library/std/src/lib.rs
index 311b2cb9323..323742a75b0 100644
--- a/library/std/src/lib.rs
+++ b/library/std/src/lib.rs
@@ -329,7 +329,6 @@
 #![feature(bstr_internals)]
 #![feature(char_internals)]
 #![feature(clone_to_uninit)]
-#![feature(const_float_round_methods)]
 #![feature(core_intrinsics)]
 #![feature(core_io_borrowed_buf)]
 #![feature(duration_constants)]
diff --git a/library/std/src/num/f32.rs b/library/std/src/num/f32.rs
index e79ec2ae966..2bff73add33 100644
--- a/library/std/src/num/f32.rs
+++ b/library/std/src/num/f32.rs
@@ -44,7 +44,7 @@ impl f32 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
+    #[rustc_const_stable(feature = "const_float_round_methods", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn floor(self) -> f32 {
         core::f32::math::floor(self)
@@ -67,7 +67,7 @@ impl f32 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
+    #[rustc_const_stable(feature = "const_float_round_methods", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn ceil(self) -> f32 {
         core::f32::math::ceil(self)
@@ -96,7 +96,7 @@ impl f32 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
+    #[rustc_const_stable(feature = "const_float_round_methods", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn round(self) -> f32 {
         core::f32::math::round(self)
@@ -123,7 +123,7 @@ impl f32 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "round_ties_even", since = "1.77.0")]
-    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
+    #[rustc_const_stable(feature = "const_float_round_methods", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn round_ties_even(self) -> f32 {
         core::f32::math::round_ties_even(self)
@@ -149,7 +149,7 @@ impl f32 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
+    #[rustc_const_stable(feature = "const_float_round_methods", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn trunc(self) -> f32 {
         core::f32::math::trunc(self)
@@ -173,7 +173,7 @@ impl f32 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
+    #[rustc_const_stable(feature = "const_float_round_methods", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn fract(self) -> f32 {
         core::f32::math::fract(self)
diff --git a/library/std/src/num/f64.rs b/library/std/src/num/f64.rs
index 853417825f9..b71e319f407 100644
--- a/library/std/src/num/f64.rs
+++ b/library/std/src/num/f64.rs
@@ -44,7 +44,7 @@ impl f64 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
+    #[rustc_const_stable(feature = "const_float_round_methods", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn floor(self) -> f64 {
         core::f64::math::floor(self)
@@ -67,7 +67,7 @@ impl f64 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
+    #[rustc_const_stable(feature = "const_float_round_methods", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn ceil(self) -> f64 {
         core::f64::math::ceil(self)
@@ -96,7 +96,7 @@ impl f64 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
+    #[rustc_const_stable(feature = "const_float_round_methods", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn round(self) -> f64 {
         core::f64::math::round(self)
@@ -123,7 +123,7 @@ impl f64 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "round_ties_even", since = "1.77.0")]
-    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
+    #[rustc_const_stable(feature = "const_float_round_methods", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn round_ties_even(self) -> f64 {
         core::f64::math::round_ties_even(self)
@@ -149,7 +149,7 @@ impl f64 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
+    #[rustc_const_stable(feature = "const_float_round_methods", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn trunc(self) -> f64 {
         core::f64::math::trunc(self)
@@ -173,7 +173,7 @@ impl f64 {
     #[rustc_allow_incoherent_impl]
     #[must_use = "method returns a new number and does not mutate the original value"]
     #[stable(feature = "rust1", since = "1.0.0")]
-    #[rustc_const_unstable(feature = "const_float_round_methods", issue = "141555")]
+    #[rustc_const_stable(feature = "const_float_round_methods", since = "CURRENT_RUSTC_VERSION")]
     #[inline]
     pub const fn fract(self) -> f64 {
         core::f64::math::fract(self)
diff --git a/library/std/src/prelude/v1.rs b/library/std/src/prelude/v1.rs
index 69f03353153..70c11131556 100644
--- a/library/std/src/prelude/v1.rs
+++ b/library/std/src/prelude/v1.rs
@@ -67,7 +67,7 @@ pub use core::prelude::v1::{
     alloc_error_handler, bench, derive, global_allocator, test, test_case,
 };
 
-#[unstable(feature = "derive_const", issue = "none")]
+#[unstable(feature = "derive_const", issue = "118304")]
 pub use core::prelude::v1::derive_const;
 
 // Do not `doc(no_inline)` either.
diff --git a/library/std/src/sync/poison.rs b/library/std/src/sync/poison.rs
index 571f0d14248..0c05f152ef8 100644
--- a/library/std/src/sync/poison.rs
+++ b/library/std/src/sync/poison.rs
@@ -10,7 +10,7 @@
 //! (some invariant is not being upheld).
 //!
 //! The specifics of how this "poisoned" state affects other threads
-//! depend on the primitive. See [#Overview] bellow.
+//! depend on the primitive. See [#Overview] below.
 //!
 //! For the alternative implementations that do not employ poisoning,
 //! see `std::sync::nonpoisoning`.
diff --git a/library/std/src/sys/backtrace.rs b/library/std/src/sys/backtrace.rs
index efa6a896dad..272d0fa4d1a 100644
--- a/library/std/src/sys/backtrace.rs
+++ b/library/std/src/sys/backtrace.rs
@@ -68,61 +68,67 @@ unsafe fn _print_fmt(fmt: &mut fmt::Formatter<'_>, print_fmt: PrintFmt) -> fmt::
                 return false;
             }
 
-            let mut hit = false;
-            backtrace_rs::resolve_frame_unsynchronized(frame, |symbol| {
-                hit = true;
-
-                // `__rust_end_short_backtrace` means we are done hiding symbols
-                // for now. Print until we see `__rust_begin_short_backtrace`.
-                if print_fmt == PrintFmt::Short {
-                    if let Some(sym) = symbol.name().and_then(|s| s.as_str()) {
-                        if sym.contains("__rust_end_short_backtrace") {
-                            print = true;
-                            return;
-                        }
-                        if print && sym.contains("__rust_begin_short_backtrace") {
-                            print = false;
-                            return;
-                        }
-                        if !print {
-                            omitted_count += 1;
+            if cfg!(feature = "backtrace-trace-only") {
+                const HEX_WIDTH: usize = 2 + 2 * size_of::<usize>();
+                let frame_ip = frame.ip();
+                res = writeln!(bt_fmt.formatter(), "{idx:4}: {frame_ip:HEX_WIDTH$?}");
+            } else {
+                let mut hit = false;
+                backtrace_rs::resolve_frame_unsynchronized(frame, |symbol| {
+                    hit = true;
+
+                    // `__rust_end_short_backtrace` means we are done hiding symbols
+                    // for now. Print until we see `__rust_begin_short_backtrace`.
+                    if print_fmt == PrintFmt::Short {
+                        if let Some(sym) = symbol.name().and_then(|s| s.as_str()) {
+                            if sym.contains("__rust_end_short_backtrace") {
+                                print = true;
+                                return;
+                            }
+                            if print && sym.contains("__rust_begin_short_backtrace") {
+                                print = false;
+                                return;
+                            }
+                            if !print {
+                                omitted_count += 1;
+                            }
                         }
                     }
-                }
 
-                if print {
-                    if omitted_count > 0 {
-                        debug_assert!(print_fmt == PrintFmt::Short);
-                        // only print the message between the middle of frames
-                        if !first_omit {
-                            let _ = writeln!(
-                                bt_fmt.formatter(),
-                                "      [... omitted {} frame{} ...]",
-                                omitted_count,
-                                if omitted_count > 1 { "s" } else { "" }
-                            );
+                    if print {
+                        if omitted_count > 0 {
+                            debug_assert!(print_fmt == PrintFmt::Short);
+                            // only print the message between the middle of frames
+                            if !first_omit {
+                                let _ = writeln!(
+                                    bt_fmt.formatter(),
+                                    "      [... omitted {} frame{} ...]",
+                                    omitted_count,
+                                    if omitted_count > 1 { "s" } else { "" }
+                                );
+                            }
+                            first_omit = false;
+                            omitted_count = 0;
                         }
-                        first_omit = false;
-                        omitted_count = 0;
+                        res = bt_fmt.frame().symbol(frame, symbol);
                     }
-                    res = bt_fmt.frame().symbol(frame, symbol);
+                });
+                #[cfg(target_os = "nto")]
+                if libc::__my_thread_exit as *mut libc::c_void == frame.ip() {
+                    if !hit && print {
+                        use crate::backtrace_rs::SymbolName;
+                        res = bt_fmt.frame().print_raw(
+                            frame.ip(),
+                            Some(SymbolName::new("__my_thread_exit".as_bytes())),
+                            None,
+                            None,
+                        );
+                    }
+                    return false;
                 }
-            });
-            #[cfg(target_os = "nto")]
-            if libc::__my_thread_exit as *mut libc::c_void == frame.ip() {
                 if !hit && print {
-                    use crate::backtrace_rs::SymbolName;
-                    res = bt_fmt.frame().print_raw(
-                        frame.ip(),
-                        Some(SymbolName::new("__my_thread_exit".as_bytes())),
-                        None,
-                        None,
-                    );
+                    res = bt_fmt.frame().print_raw(frame.ip(), None, None, None);
                 }
-                return false;
-            }
-            if !hit && print {
-                res = bt_fmt.frame().print_raw(frame.ip(), None, None, None);
             }
 
             idx += 1;
diff --git a/library/std/src/sys/pal/windows/c.rs b/library/std/src/sys/pal/windows/c.rs
index eee169d410a..edac5262a4e 100644
--- a/library/std/src/sys/pal/windows/c.rs
+++ b/library/std/src/sys/pal/windows/c.rs
@@ -197,7 +197,7 @@ compat_fn_optional! {
     pub fn WakeByAddressSingle(address: *const c_void);
 }
 
-#[cfg(any(target_vendor = "win7", target_vendor = "uwp"))]
+#[cfg(any(target_vendor = "win7"))]
 compat_fn_with_fallback! {
     pub static NTDLL: &CStr = c"ntdll";
 
@@ -228,65 +228,14 @@ compat_fn_with_fallback! {
     ) -> NTSTATUS {
         panic!("keyed events not available")
     }
+}
 
-    // These functions are available on UWP when lazily loaded. They will fail WACK if loaded statically.
-    #[cfg(target_vendor = "uwp")]
-    pub fn NtCreateFile(
-        filehandle: *mut HANDLE,
-        desiredaccess: FILE_ACCESS_RIGHTS,
-        objectattributes: *const OBJECT_ATTRIBUTES,
-        iostatusblock: *mut IO_STATUS_BLOCK,
-        allocationsize: *const i64,
-        fileattributes: FILE_FLAGS_AND_ATTRIBUTES,
-        shareaccess: FILE_SHARE_MODE,
-        createdisposition: NTCREATEFILE_CREATE_DISPOSITION,
-        createoptions: NTCREATEFILE_CREATE_OPTIONS,
-        eabuffer: *const c_void,
-        ealength: u32
-    ) -> NTSTATUS {
-        STATUS_NOT_IMPLEMENTED
-    }
-    #[cfg(target_vendor = "uwp")]
-    pub fn NtOpenFile(
-        filehandle: *mut HANDLE,
-        desiredaccess: u32,
-        objectattributes: *const OBJECT_ATTRIBUTES,
-        iostatusblock: *mut IO_STATUS_BLOCK,
-        shareaccess: u32,
-        openoptions: u32
-    ) -> NTSTATUS {
-        STATUS_NOT_IMPLEMENTED
-    }
-    #[cfg(target_vendor = "uwp")]
-    pub fn NtReadFile(
-        filehandle: HANDLE,
-        event: HANDLE,
-        apcroutine: PIO_APC_ROUTINE,
-        apccontext: *const c_void,
-        iostatusblock: *mut IO_STATUS_BLOCK,
-        buffer: *mut c_void,
-        length: u32,
-        byteoffset: *const i64,
-        key: *const u32
-    ) -> NTSTATUS {
-        STATUS_NOT_IMPLEMENTED
-    }
-    #[cfg(target_vendor = "uwp")]
-    pub fn NtWriteFile(
-        filehandle: HANDLE,
-        event: HANDLE,
-        apcroutine: PIO_APC_ROUTINE,
-        apccontext: *const c_void,
-        iostatusblock: *mut IO_STATUS_BLOCK,
-        buffer: *const c_void,
-        length: u32,
-        byteoffset: *const i64,
-        key: *const u32
-    ) -> NTSTATUS {
-        STATUS_NOT_IMPLEMENTED
-    }
-    #[cfg(target_vendor = "uwp")]
-    pub fn RtlNtStatusToDosError(Status: NTSTATUS) -> u32 {
-        Status as u32
+cfg_if::cfg_if! {
+    if #[cfg(target_vendor = "uwp")] {
+        windows_targets::link_raw_dylib!("ntdll.dll" "system" fn NtCreateFile(filehandle : *mut HANDLE, desiredaccess : FILE_ACCESS_RIGHTS, objectattributes : *const OBJECT_ATTRIBUTES, iostatusblock : *mut IO_STATUS_BLOCK, allocationsize : *const i64, fileattributes : FILE_FLAGS_AND_ATTRIBUTES, shareaccess : FILE_SHARE_MODE, createdisposition : NTCREATEFILE_CREATE_DISPOSITION, createoptions : NTCREATEFILE_CREATE_OPTIONS, eabuffer : *const core::ffi::c_void, ealength : u32) -> NTSTATUS);
+        windows_targets::link_raw_dylib!("ntdll.dll" "system" fn NtOpenFile(filehandle : *mut HANDLE, desiredaccess : u32, objectattributes : *const OBJECT_ATTRIBUTES, iostatusblock : *mut IO_STATUS_BLOCK, shareaccess : u32, openoptions : u32) -> NTSTATUS);
+        windows_targets::link_raw_dylib!("ntdll.dll" "system" fn NtReadFile(filehandle : HANDLE, event : HANDLE, apcroutine : PIO_APC_ROUTINE, apccontext : *const core::ffi::c_void, iostatusblock : *mut IO_STATUS_BLOCK, buffer : *mut core::ffi::c_void, length : u32, byteoffset : *const i64, key : *const u32) -> NTSTATUS);
+        windows_targets::link_raw_dylib!("ntdll.dll" "system" fn NtWriteFile(filehandle : HANDLE, event : HANDLE, apcroutine : PIO_APC_ROUTINE, apccontext : *const core::ffi::c_void, iostatusblock : *mut IO_STATUS_BLOCK, buffer : *const core::ffi::c_void, length : u32, byteoffset : *const i64, key : *const u32) -> NTSTATUS);
+        windows_targets::link_raw_dylib!("ntdll.dll" "system" fn RtlNtStatusToDosError(status : NTSTATUS) -> u32);
     }
 }
diff --git a/library/std/src/thread/local.rs b/library/std/src/thread/local.rs
index 7cd44873313..0ad014ccd3e 100644
--- a/library/std/src/thread/local.rs
+++ b/library/std/src/thread/local.rs
@@ -469,6 +469,29 @@ impl<T: 'static> LocalKey<Cell<T>> {
     pub fn replace(&'static self, value: T) -> T {
         self.with(|cell| cell.replace(value))
     }
+
+    /// Updates the contained value using a function.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// #![feature(local_key_cell_update)]
+    /// use std::cell::Cell;
+    ///
+    /// thread_local! {
+    ///     static X: Cell<i32> = const { Cell::new(5) };
+    /// }
+    ///
+    /// X.update(|x| x + 1);
+    /// assert_eq!(X.get(), 6);
+    /// ```
+    #[unstable(feature = "local_key_cell_update", issue = "143989")]
+    pub fn update(&'static self, f: impl FnOnce(T) -> T)
+    where
+        T: Copy,
+    {
+        self.with(|cell| cell.update(f))
+    }
 }
 
 impl<T: 'static> LocalKey<RefCell<T>> {