Auto merge of #3635 - RalfJung:rustup, r=RalfJung

Rustup

10 files changed, 118 insertions, 51 deletions

diff --git a/library/std/Cargo.toml b/library/std/Cargo.toml
index e56f03808b3..bc78c63c577 100644
--- a/library/std/Cargo.toml
+++ b/library/std/Cargo.toml
@@ -102,7 +102,6 @@ test = true
 level = "warn"
 # x.py uses beta cargo, so `check-cfg` entries do not yet take effect
 # for rust-lang/rust. But for users of `-Zbuild-std` it does.
-# The unused warning is waiting for rust-lang/cargo#13925 to reach beta.
 check-cfg = [
     'cfg(bootstrap)',
     'cfg(target_arch, values("xtensa"))',
diff --git a/library/std/src/lib.rs b/library/std/src/lib.rs
index 4a18db3d5a3..9d6576fa841 100644
--- a/library/std/src/lib.rs
+++ b/library/std/src/lib.rs
@@ -395,7 +395,6 @@
 #![feature(edition_panic)]
 #![feature(format_args_nl)]
 #![feature(get_many_mut)]
-#![feature(lazy_cell)]
 #![feature(log_syntax)]
 #![feature(test)]
 #![feature(trace_macros)]
diff --git a/library/std/src/path.rs b/library/std/src/path.rs
index f835b69f0cf..f4e1e2a38c1 100644
--- a/library/std/src/path.rs
+++ b/library/std/src/path.rs
@@ -1425,6 +1425,11 @@ impl PathBuf {
     /// If `extension` is the empty string, [`self.extension`] will be [`None`]
     /// afterwards, not `Some("")`.
     ///
+    /// # Panics
+    ///
+    /// Panics if the passed extension contains a path separator (see
+    /// [`is_separator`]).
+    ///
     /// # Caveats
     ///
     /// The new `extension` may contain dots and will be used in its entirety,
@@ -1470,6 +1475,14 @@ impl PathBuf {
     }
 
     fn _set_extension(&mut self, extension: &OsStr) -> bool {
+        for &b in extension.as_encoded_bytes() {
+            if b < 128 {
+                if is_separator(b as char) {
+                    panic!("extension cannot contain path separators: {:?}", extension);
+                }
+            }
+        }
+
         let file_stem = match self.file_stem() {
             None => return false,
             Some(f) => f.as_encoded_bytes(),
diff --git a/library/std/src/path/tests.rs b/library/std/src/path/tests.rs
index fde6ed4f0c0..2d8e50d1f88 100644
--- a/library/std/src/path/tests.rs
+++ b/library/std/src/path/tests.rs
@@ -1803,6 +1803,29 @@ fn test_windows_absolute() {
     assert_eq!(absolute(r"COM1").unwrap().as_os_str(), Path::new(r"\\.\COM1").as_os_str());
 }
 
+#[test]
+#[should_panic = "path separator"]
+fn test_extension_path_sep() {
+    let mut path = PathBuf::from("path/to/file");
+    path.set_extension("d/../../../../../etc/passwd");
+}
+
+#[test]
+#[should_panic = "path separator"]
+#[cfg(windows)]
+fn test_extension_path_sep_alternate() {
+    let mut path = PathBuf::from("path/to/file");
+    path.set_extension("d\\test");
+}
+
+#[test]
+#[cfg(not(windows))]
+fn test_extension_path_sep_alternate() {
+    let mut path = PathBuf::from("path/to/file");
+    path.set_extension("d\\test");
+    assert_eq!(path, Path::new("path/to/file.d\\test"));
+}
+
 #[bench]
 #[cfg_attr(miri, ignore)] // Miri isn't fast...
 fn bench_path_cmp_fast_path_buf_sort(b: &mut test::Bencher) {
diff --git a/library/std/src/sync/lazy_lock.rs b/library/std/src/sync/lazy_lock.rs
index 27b59cfc8c2..16d5dc30552 100644
--- a/library/std/src/sync/lazy_lock.rs
+++ b/library/std/src/sync/lazy_lock.rs
@@ -31,8 +31,6 @@ union Data<T, F> {
 /// Initialize static variables with `LazyLock`.
 ///
 /// ```
-/// #![feature(lazy_cell)]
-///
 /// use std::collections::HashMap;
 ///
 /// use std::sync::LazyLock;
@@ -61,8 +59,6 @@ union Data<T, F> {
 /// ```
 /// Initialize fields with `LazyLock`.
 /// ```
-/// #![feature(lazy_cell)]
-///
 /// use std::sync::LazyLock;
 ///
 /// #[derive(Debug)]
@@ -76,8 +72,7 @@ union Data<T, F> {
 ///     println!("{}", *data.number);
 /// }
 /// ```
-
-#[unstable(feature = "lazy_cell", issue = "109736")]
+#[stable(feature = "lazy_cell", since = "CURRENT_RUSTC_VERSION")]
 pub struct LazyLock<T, F = fn() -> T> {
     once: Once,
     data: UnsafeCell<Data<T, F>>,
@@ -85,8 +80,21 @@ pub struct LazyLock<T, F = fn() -> T> {
 
 impl<T, F: FnOnce() -> T> LazyLock<T, F> {
     /// Creates a new lazy value with the given initializing function.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::sync::LazyLock;
+    ///
+    /// let hello = "Hello, World!".to_string();
+    ///
+    /// let lazy = LazyLock::new(|| hello.to_uppercase());
+    ///
+    /// assert_eq!(&*lazy, "HELLO, WORLD!");
+    /// ```
     #[inline]
-    #[unstable(feature = "lazy_cell", issue = "109736")]
+    #[stable(feature = "lazy_cell", since = "CURRENT_RUSTC_VERSION")]
+    #[rustc_const_stable(feature = "lazy_cell", since = "CURRENT_RUSTC_VERSION")]
     pub const fn new(f: F) -> LazyLock<T, F> {
         LazyLock { once: Once::new(), data: UnsafeCell::new(Data { f: ManuallyDrop::new(f) }) }
     }
@@ -107,7 +115,6 @@ impl<T, F: FnOnce() -> T> LazyLock<T, F> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(lazy_cell)]
     /// #![feature(lazy_cell_consume)]
     ///
     /// use std::sync::LazyLock;
@@ -145,8 +152,6 @@ impl<T, F: FnOnce() -> T> LazyLock<T, F> {
     /// # Examples
     ///
     /// ```
-    /// #![feature(lazy_cell)]
-    ///
     /// use std::sync::LazyLock;
     ///
     /// let lazy = LazyLock::new(|| 92);
@@ -155,7 +160,7 @@ impl<T, F: FnOnce() -> T> LazyLock<T, F> {
     /// assert_eq!(&*lazy, &92);
     /// ```
     #[inline]
-    #[unstable(feature = "lazy_cell", issue = "109736")]
+    #[stable(feature = "lazy_cell", since = "CURRENT_RUSTC_VERSION")]
     pub fn force(this: &LazyLock<T, F>) -> &T {
         this.once.call_once(|| {
             // SAFETY: `call_once` only runs this closure once, ever.
@@ -191,7 +196,7 @@ impl<T, F> LazyLock<T, F> {
     }
 }
 
-#[unstable(feature = "lazy_cell", issue = "109736")]
+#[stable(feature = "lazy_cell", since = "CURRENT_RUSTC_VERSION")]
 impl<T, F> Drop for LazyLock<T, F> {
     fn drop(&mut self) {
         match self.once.state() {
@@ -204,7 +209,7 @@ impl<T, F> Drop for LazyLock<T, F> {
     }
 }
 
-#[unstable(feature = "lazy_cell", issue = "109736")]
+#[stable(feature = "lazy_cell", since = "CURRENT_RUSTC_VERSION")]
 impl<T, F: FnOnce() -> T> Deref for LazyLock<T, F> {
     type Target = T;
 
@@ -219,7 +224,7 @@ impl<T, F: FnOnce() -> T> Deref for LazyLock<T, F> {
     }
 }
 
-#[unstable(feature = "lazy_cell", issue = "109736")]
+#[stable(feature = "lazy_cell", since = "CURRENT_RUSTC_VERSION")]
 impl<T: Default> Default for LazyLock<T> {
     /// Creates a new lazy value using `Default` as the initializing function.
     #[inline]
@@ -228,7 +233,7 @@ impl<T: Default> Default for LazyLock<T> {
     }
 }
 
-#[unstable(feature = "lazy_cell", issue = "109736")]
+#[stable(feature = "lazy_cell", since = "CURRENT_RUSTC_VERSION")]
 impl<T: fmt::Debug, F> fmt::Debug for LazyLock<T, F> {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         let mut d = f.debug_tuple("LazyLock");
@@ -242,13 +247,13 @@ impl<T: fmt::Debug, F> fmt::Debug for LazyLock<T, F> {
 
 // We never create a `&F` from a `&LazyLock<T, F>` so it is fine
 // to not impl `Sync` for `F`.
-#[unstable(feature = "lazy_cell", issue = "109736")]
+#[stable(feature = "lazy_cell", since = "CURRENT_RUSTC_VERSION")]
 unsafe impl<T: Sync + Send, F: Send> Sync for LazyLock<T, F> {}
 // auto-derived `Send` impl is OK.
 
-#[unstable(feature = "lazy_cell", issue = "109736")]
+#[stable(feature = "lazy_cell", since = "CURRENT_RUSTC_VERSION")]
 impl<T: RefUnwindSafe + UnwindSafe, F: UnwindSafe> RefUnwindSafe for LazyLock<T, F> {}
-#[unstable(feature = "lazy_cell", issue = "109736")]
+#[stable(feature = "lazy_cell", since = "CURRENT_RUSTC_VERSION")]
 impl<T: UnwindSafe, F: UnwindSafe> UnwindSafe for LazyLock<T, F> {}
 
 #[cfg(test)]
diff --git a/library/std/src/sync/mod.rs b/library/std/src/sync/mod.rs
index e8c35bd48a7..fb7d601b094 100644
--- a/library/std/src/sync/mod.rs
+++ b/library/std/src/sync/mod.rs
@@ -179,7 +179,7 @@ pub use self::rwlock::{MappedRwLockReadGuard, MappedRwLockWriteGuard};
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use self::rwlock::{RwLock, RwLockReadGuard, RwLockWriteGuard};
 
-#[unstable(feature = "lazy_cell", issue = "109736")]
+#[stable(feature = "lazy_cell", since = "CURRENT_RUSTC_VERSION")]
 pub use self::lazy_lock::LazyLock;
 #[stable(feature = "once_cell", since = "1.70.0")]
 pub use self::once_lock::OnceLock;
diff --git a/library/std/src/sync/reentrant_lock.rs b/library/std/src/sync/reentrant_lock.rs
index 80b9e0cf152..f7fe8eb1c7f 100644
--- a/library/std/src/sync/reentrant_lock.rs
+++ b/library/std/src/sync/reentrant_lock.rs
@@ -117,6 +117,9 @@ pub struct ReentrantLockGuard<'a, T: ?Sized + 'a> {
 impl<T: ?Sized> !Send for ReentrantLockGuard<'_, T> {}
 
 #[unstable(feature = "reentrant_lock", issue = "121440")]
+unsafe impl<T: ?Sized + Sync> Sync for ReentrantLockGuard<'_, T> {}
+
+#[unstable(feature = "reentrant_lock", issue = "121440")]
 impl<T> ReentrantLock<T> {
     /// Creates a new re-entrant lock in an unlocked state ready for use.
     ///
diff --git a/library/std/src/sys/pal/unix/alloc.rs b/library/std/src/sys/pal/unix/alloc.rs
index 2f908e3d0e9..eb3a57c212b 100644
--- a/library/std/src/sys/pal/unix/alloc.rs
+++ b/library/std/src/sys/pal/unix/alloc.rs
@@ -59,10 +59,9 @@ unsafe impl GlobalAlloc for System {
 }
 
 cfg_if::cfg_if! {
-    // We use posix_memalign wherever possible, but not all targets have that function.
+    // We use posix_memalign wherever possible, but some targets have very incomplete POSIX coverage
+    // so we need a fallback for those.
     if #[cfg(any(
-        target_os = "redox",
-        target_os = "espidf",
         target_os = "horizon",
         target_os = "vita",
     ))] {
@@ -74,12 +73,11 @@ cfg_if::cfg_if! {
         #[inline]
         unsafe fn aligned_malloc(layout: &Layout) -> *mut u8 {
             let mut out = ptr::null_mut();
-            // We prefer posix_memalign over aligned_malloc since with aligned_malloc,
-            // implementations are making almost arbitrary choices for which alignments are
-            // "supported", making it hard to use. For instance, some implementations require the
-            // size to be a multiple of the alignment (wasi emmalloc), while others require the
-            // alignment to be at least the pointer size (Illumos, macOS) -- which may or may not be
-            // standards-compliant, but that does not help us.
+            // We prefer posix_memalign over aligned_alloc since it is more widely available, and
+            // since with aligned_alloc, implementations are making almost arbitrary choices for
+            // which alignments are "supported", making it hard to use. For instance, some
+            // implementations require the size to be a multiple of the alignment (wasi emmalloc),
+            // while others require the alignment to be at least the pointer size (Illumos, macOS).
             // posix_memalign only has one, clear requirement: that the alignment be a multiple of
             // `sizeof(void*)`. Since these are all powers of 2, we can just use max.
             let align = layout.align().max(crate::mem::size_of::<usize>());
diff --git a/library/std/src/sys/pal/unix/kernel_copy.rs b/library/std/src/sys/pal/unix/kernel_copy.rs
index 18acd5ecccd..cd38b7c07e2 100644
--- a/library/std/src/sys/pal/unix/kernel_copy.rs
+++ b/library/std/src/sys/pal/unix/kernel_copy.rs
@@ -560,6 +560,12 @@ pub(super) fn copy_regular_files(reader: RawFd, writer: RawFd, max_len: u64) ->
     // We store the availability in a global to avoid unnecessary syscalls
     static HAS_COPY_FILE_RANGE: AtomicU8 = AtomicU8::new(NOT_PROBED);
 
+    let mut have_probed = match HAS_COPY_FILE_RANGE.load(Ordering::Relaxed) {
+        NOT_PROBED => false,
+        UNAVAILABLE => return CopyResult::Fallback(0),
+        _ => true,
+    };
+
     syscall! {
         fn copy_file_range(
             fd_in: libc::c_int,
@@ -571,25 +577,22 @@ pub(super) fn copy_regular_files(reader: RawFd, writer: RawFd, max_len: u64) ->
         ) -> libc::ssize_t
     }
 
-    match HAS_COPY_FILE_RANGE.load(Ordering::Relaxed) {
-        NOT_PROBED => {
-            // EPERM can indicate seccomp filters or an immutable file.
-            // To distinguish these cases we probe with invalid file descriptors which should result in EBADF if the syscall is supported
-            // and some other error (ENOSYS or EPERM) if it's not available
-            let result = unsafe {
-                cvt(copy_file_range(INVALID_FD, ptr::null_mut(), INVALID_FD, ptr::null_mut(), 1, 0))
-            };
-
-            if matches!(result.map_err(|e| e.raw_os_error()), Err(Some(EBADF))) {
-                HAS_COPY_FILE_RANGE.store(AVAILABLE, Ordering::Relaxed);
-            } else {
-                HAS_COPY_FILE_RANGE.store(UNAVAILABLE, Ordering::Relaxed);
-                return CopyResult::Fallback(0);
-            }
+    fn probe_copy_file_range_support() -> u8 {
+        // In some cases, we cannot determine availability from the first
+        // `copy_file_range` call. In this case, we probe with an invalid file
+        // descriptor so that the results are easily interpretable.
+        match unsafe {
+            cvt(copy_file_range(INVALID_FD, ptr::null_mut(), INVALID_FD, ptr::null_mut(), 1, 0))
+                .map_err(|e| e.raw_os_error())
+        } {
+            Err(Some(EPERM | ENOSYS)) => UNAVAILABLE,
+            Err(Some(EBADF)) => AVAILABLE,
+            Ok(_) => panic!("unexpected copy_file_range probe success"),
+            // Treat other errors as the syscall
+            // being unavailable.
+            Err(_) => UNAVAILABLE,
         }
-        UNAVAILABLE => return CopyResult::Fallback(0),
-        _ => {}
-    };
+    }
 
     let mut written = 0u64;
     while written < max_len {
@@ -604,6 +607,11 @@ pub(super) fn copy_regular_files(reader: RawFd, writer: RawFd, max_len: u64) ->
             cvt(copy_file_range(reader, ptr::null_mut(), writer, ptr::null_mut(), bytes_to_copy, 0))
         };
 
+        if !have_probed && copy_result.is_ok() {
+            have_probed = true;
+            HAS_COPY_FILE_RANGE.store(AVAILABLE, Ordering::Relaxed);
+        }
+
         match copy_result {
             Ok(0) if written == 0 => {
                 // fallback to work around several kernel bugs where copy_file_range will fail to
@@ -619,7 +627,28 @@ pub(super) fn copy_regular_files(reader: RawFd, writer: RawFd, max_len: u64) ->
                 return match err.raw_os_error() {
                     // when file offset + max_length > u64::MAX
                     Some(EOVERFLOW) => CopyResult::Fallback(written),
-                    Some(ENOSYS | EXDEV | EINVAL | EPERM | EOPNOTSUPP | EBADF) if written == 0 => {
+                    Some(raw_os_error @ (ENOSYS | EXDEV | EINVAL | EPERM | EOPNOTSUPP | EBADF))
+                        if written == 0 =>
+                    {
+                        if !have_probed {
+                            let available = if matches!(raw_os_error, ENOSYS | EOPNOTSUPP | EPERM) {
+                                // EPERM can indicate seccomp filters or an
+                                // immutable file. To distinguish these
+                                // cases we probe with invalid file
+                                // descriptors which should result in EBADF
+                                // if the syscall is supported and EPERM or
+                                // ENOSYS if it's not available.
+                                //
+                                // For EOPNOTSUPP, see below. In the case of
+                                // ENOSYS, we try to cover for faulty FUSE
+                                // drivers.
+                                probe_copy_file_range_support()
+                            } else {
+                                AVAILABLE
+                            };
+                            HAS_COPY_FILE_RANGE.store(available, Ordering::Relaxed);
+                        }
+
                         // Try fallback io::copy if either:
                         // - Kernel version is < 4.5 (ENOSYS¹)
                         // - Files are mounted on different fs (EXDEV)
diff --git a/library/std/tests/run-time-detect.rs b/library/std/tests/run-time-detect.rs
index c9b9c54e3d4..69486705656 100644
--- a/library/std/tests/run-time-detect.rs
+++ b/library/std/tests/run-time-detect.rs
@@ -121,10 +121,8 @@ fn x86_all() {
     println!("avx512bw: {:?}", is_x86_feature_detected!("avx512bw"));
     println!("avx512cd: {:?}", is_x86_feature_detected!("avx512cd"));
     println!("avx512dq: {:?}", is_x86_feature_detected!("avx512dq"));
-    println!("avx512er: {:?}", is_x86_feature_detected!("avx512er"));
     println!("avx512f: {:?}", is_x86_feature_detected!("avx512f"));
     println!("avx512ifma: {:?}", is_x86_feature_detected!("avx512ifma"));
-    println!("avx512pf: {:?}", is_x86_feature_detected!("avx512pf"));
     println!("avx512vbmi2: {:?}", is_x86_feature_detected!("avx512vbmi2"));
     println!("avx512vbmi: {:?}", is_x86_feature_detected!("avx512vbmi"));
     println!("avx512vl: {:?}", is_x86_feature_detected!("avx512vl"));