Auto merge of rust-lang#103604 - JohnTitor:rollup-q4ns2gh, r=JohnTitor

Rollup of 10 pull requests

Successful merges:

 - rust-lang#103432 (rustdoc: don't mark Box<T> as Iterator, Read, etc)
 - rust-lang#103526 (More dupe typos again)
 - rust-lang#103537 (rustdoc: combine shared CSS between `.*-line-numbers`)
 - rust-lang#103549 (llvm-16: Don't initialize removed legacy passes)
 - rust-lang#103558 (Update cargo)
 - rust-lang#103567 (ptr::eq: clarify that comparing dyn Trait is fragile)
 - rust-lang#103579 (:arrow_up: rust-analyzer)
 - rust-lang#103580 (Fix typo in docs for `guaranteed_ne`)
 - rust-lang#103596 (thread::set_name: debug-assert that things went well)
 - rust-lang#103598 (rustc_lexer::TokenKind improve docs)

Failed merges:

 - rust-lang#103585 (Migrate source line numbers CSS to CSS variables)

r? `@ghost`
`@rustbot` modify labels: rollup

Author: bors

compiler/rustc_lexer/src/lib.rs

@@ -57,29 +57,42 @@ pub enum TokenKind {
     // Multi-char tokens:
     /// "// comment"
     LineComment { doc_style: Option<DocStyle> },
+
     /// `/* block comment */`
     ///
-    /// Block comments can be recursive, so the sequence like `/* /* */`
+    /// Block comments can be recursive, so a sequence like `/* /* */`
     /// will not be considered terminated and will result in a parsing error.
     BlockComment { doc_style: Option<DocStyle>, terminated: bool },
-    /// Any whitespace characters sequence.
+
+    /// Any whitespace character sequence.
     Whitespace,
+
     /// "ident" or "continue"
-    /// At this step keywords are also considered identifiers.
+    ///
+    /// At this step, keywords are also considered identifiers.
     Ident,
+
     /// Like the above, but containing invalid unicode codepoints.
     InvalidIdent,
+
     /// "r#ident"
     RawIdent,
-    /// An unknown prefix like `foo#`, `foo'`, `foo"`. Note that only the
+
+    /// An unknown prefix, like `foo#`, `foo'`, `foo"`.
+    ///
+    /// Note that only the
     /// prefix (`foo`) is included in the token, not the separator (which is
     /// lexed as its own distinct token). In Rust 2021 and later, reserved
     /// prefixes are reported as errors; in earlier editions, they result in a
     /// (allowed by default) lint, and are treated as regular identifier
     /// tokens.
     UnknownPrefix,
-    /// "12_u8", "1.0e-40", "b"123"". See `LiteralKind` for more details.
+
+    /// Examples: `"12_u8"`, `"1.0e-40"`, `b"123`.
+    ///
+    /// See [LiteralKind] for more details.
     Literal { kind: LiteralKind, suffix_start: u32 },
+
     /// "'a"
     Lifetime { starts_with_number: bool },
 

compiler/rustc_llvm/llvm-wrapper/PassWrapper.cpp

@@ -69,7 +69,9 @@ extern "C" void LLVMInitializePasses() {
   initializeAnalysis(Registry);
   initializeTransformUtils(Registry);
   initializeInstCombine(Registry);
+#if LLVM_VERSION_LT(16, 0)
   initializeInstrumentation(Registry);
+#endif
   initializeTarget(Registry);
 }
 

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
     ///
@@ -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
     ///

library/alloc/src/sync.rs

@@ -1117,8 +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
     ///
@@ -2069,9 +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
     ///

library/core/src/ptr/const_ptr.rs

@@ -802,7 +802,7 @@ impl<T: ?Sized> *const T {
 
     /// Returns whether two pointers are guaranteed to be inequal.
     ///
-    /// At runtime this function behaves like `Some(self == other)`.
+    /// At runtime this function behaves like `Some(self != other)`.
     /// However, in some contexts (e.g., compile-time evaluation),
     /// it is not always possible to determine inequality of two pointers, so this function may
     /// spuriously return `None` for pointers that later actually turn out to have its inequality known.

library/core/src/ptr/mod.rs

@@ -1733,6 +1733,12 @@ pub(crate) unsafe fn align_offset<T: Sized>(p: *const T, a: usize) -> usize {
 /// by their address rather than comparing the values they point to
 /// (which is what the `PartialEq for &T` implementation does).
 ///
+/// When comparing wide pointers, both the address and the metadata are tested for equality.
+/// However, note that comparing trait object pointers (`*const dyn Trait`) is unrealiable: pointers
+/// to values of the same underlying type can compare inequal (because vtables are duplicated in
+/// multiple codegen units), and pointers to values of *different* underlying type can compare equal
+/// (since identical vtables can be deduplicated within a codegen unit).
+///
 /// # Examples
 ///
 /// ```
@@ -1759,41 +1765,6 @@ pub(crate) unsafe fn align_offset<T: Sized>(p: *const T, a: usize) -> usize {
 /// assert!(!std::ptr::eq(&a[..2], &a[..3]));
 /// assert!(!std::ptr::eq(&a[0..2], &a[1..3]));
 /// ```
-///
-/// Traits are also compared by their implementation:
-///
-/// ```
-/// #[repr(transparent)]
-/// struct Wrapper { member: i32 }
-///
-/// trait Trait {}
-/// impl Trait for Wrapper {}
-/// impl Trait for i32 {}
-///
-/// let wrapper = Wrapper { member: 10 };
-///
-/// // Pointers have equal addresses.
-/// assert!(std::ptr::eq(
-///     &wrapper as *const Wrapper as *const u8,
-///     &wrapper.member as *const i32 as *const u8
-/// ));
-///
-/// // Objects have equal addresses, but `Trait` has different implementations.
-/// assert!(!std::ptr::eq(
-///     &wrapper as &dyn Trait,
-///     &wrapper.member as &dyn Trait,
-/// ));
-/// assert!(!std::ptr::eq(
-///     &wrapper as &dyn Trait as *const dyn Trait,
-///     &wrapper.member as &dyn Trait as *const dyn Trait,
-/// ));
-///
-/// // Converting the reference to a `*const u8` compares by address.
-/// assert!(std::ptr::eq(
-///     &wrapper as &dyn Trait as *const dyn Trait as *const u8,
-///     &wrapper.member as &dyn Trait as *const dyn Trait as *const u8,
-/// ));
-/// ```
 #[stable(feature = "ptr_eq", since = "1.17.0")]
 #[inline]
 pub fn eq<T: ?Sized>(a: *const T, b: *const T) -> bool {

library/core/src/ptr/mut_ptr.rs

@@ -730,7 +730,7 @@ impl<T: ?Sized> *mut T {
 
     /// Returns whether two pointers are guaranteed to be inequal.
     ///
-    /// At runtime this function behaves like `Some(self == other)`.
+    /// At runtime this function behaves like `Some(self != other)`.
     /// However, in some contexts (e.g., compile-time evaluation),
     /// it is not always possible to determine inequality of two pointers, so this function may
     /// spuriously return `None` for pointers that later actually turn out to have its inequality known.

library/std/src/sync/mpsc/stream.rs

@@ -114,7 +114,7 @@ impl<T> Packet<T> {
         match self.queue.producer_addition().cnt.fetch_add(1, Ordering::SeqCst) {
             // As described in the mod's doc comment, -1 == wakeup
             -1 => UpWoke(self.take_to_wake()),
-            // As as described before, SPSC queues must be >= -2
+            // As described before, SPSC queues must be >= -2
             -2 => UpSuccess,
 
             // Be sure to preserve the disconnected state, and the return value

library/std/src/sys/unix/thread.rs

@@ -137,7 +137,9 @@ impl Thread {
         unsafe {
             // Available since glibc 2.12, musl 1.1.16, and uClibc 1.0.20.
             let name = truncate_cstr(name, TASK_COMM_LEN);
-            libc::pthread_setname_np(libc::pthread_self(), name.as_ptr());
+            let res = libc::pthread_setname_np(libc::pthread_self(), name.as_ptr());
+            // We have no good way of propagating errors here, but in debug-builds let's check that this actually worked.
+            debug_assert_eq!(res, 0);
         }
     }
 
@@ -152,19 +154,22 @@ impl Thread {
     pub fn set_name(name: &CStr) {
         unsafe {
             let name = truncate_cstr(name, libc::MAXTHREADNAMESIZE);
-            libc::pthread_setname_np(name.as_ptr());
+            let res = libc::pthread_setname_np(name.as_ptr());
+            // We have no good way of propagating errors here, but in debug-builds let's check that this actually worked.
+            debug_assert_eq!(res, 0);
         }
     }
 
     #[cfg(target_os = "netbsd")]
     pub fn set_name(name: &CStr) {
         unsafe {
             let cname = CStr::from_bytes_with_nul_unchecked(b"%s\0".as_slice());
-            libc::pthread_setname_np(
+            let res = libc::pthread_setname_np(
                 libc::pthread_self(),
                 cname.as_ptr(),
                 name.as_ptr() as *mut libc::c_void,
             );
+            debug_assert_eq!(res, 0);
         }
     }
 
@@ -177,9 +182,8 @@ impl Thread {
         }
 
         if let Some(f) = pthread_setname_np.get() {
-            unsafe {
-                f(libc::pthread_self(), name.as_ptr());
-            }
+            let res = unsafe { f(libc::pthread_self(), name.as_ptr()) };
+            debug_assert_eq!(res, 0);
         }
     }
 

src/librustdoc/html/render/mod.rs

@@ -1276,6 +1276,15 @@ fn notable_traits_decl(decl: &clean::FnDecl, cx: &Context<'_>) -> String {
 
     if let Some((did, ty)) = decl.output.as_return().and_then(|t| Some((t.def_id(cx.cache())?, t)))
     {
+        // Box has pass-through impls for Read, Write, Iterator, and Future when the
+        // boxed type implements one of those. We don't want to treat every Box return
+        // as being notably an Iterator (etc), though, so we exempt it. Pin has the same
+        // issue, with a pass-through impl for Future.
+        if Some(did) == cx.tcx().lang_items().owned_box()
+            || Some(did) == cx.tcx().lang_items().pin_type()
+        {
+            return "".to_string();
+        }
         if let Some(impls) = cx.cache().impls.get(&did) {
             for i in impls {
                 let impl_ = i.inner_impl();