Auto merge of rust-lang#133189 - GuillaumeGomez:rollup-rhylr1f, r=GuillaumeGomez

Rollup of 6 pull requests

Successful merges:

 - rust-lang#132577 (Report the `unexpected_cfgs` lint in external macros)
 - rust-lang#132758 (Improve `{BTreeMap,HashMap}::get_key_value` docs.)
 - rust-lang#133180 ([rustdoc] Fix items with generics not having their jump to def link generated)
 - rust-lang#133181 (Update books)
 - rust-lang#133182 (const_panic: inline in bootstrap builds to avoid f16/f128 crashes)
 - rust-lang#133187 (Add reference annotations for diagnostic attributes)

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

Author: bors

Cargo.lock

@@ -111,9 +111,9 @@ dependencies = [
 
 [[package]]
 name = "anstream"
-version = "0.6.17"
+version = "0.6.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "23a1e53f0f5d86382dafe1cf314783b2044280f406e7e1506368220ad11b1338"
+checksum = "8acc5369981196006228e28809f761875c0327210a891e941f4c683b3a99529b"
 dependencies = [
  "anstyle",
  "anstyle-parse",

compiler/rustc_lint_defs/src/builtin.rs

@@ -3185,6 +3185,7 @@ declare_lint! {
     pub UNEXPECTED_CFGS,
     Warn,
     "detects unexpected names and values in `#[cfg]` conditions",
+    report_in_external_macro
 }
 
 declare_lint! {

library/alloc/src/collections/btree/map.rs

@@ -677,20 +677,58 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> {
         }
     }
 
-    /// Returns the key-value pair corresponding to the supplied key.
+    /// Returns the key-value pair corresponding to the supplied key. This is
+    /// potentially useful:
+    /// - for key types where non-identical keys can be considered equal;
+    /// - for getting the `&K` stored key value from a borrowed `&Q` lookup key; or
+    /// - for getting a reference to a key with the same lifetime as the collection.
     ///
     /// The supplied key may be any borrowed form of the map's key type, but the ordering
     /// on the borrowed form *must* match the ordering on the key type.
     ///
     /// # Examples
     ///
     /// ```
+    /// use std::cmp::Ordering;
     /// use std::collections::BTreeMap;
     ///
+    /// #[derive(Clone, Copy, Debug)]
+    /// struct S {
+    ///     id: u32,
+    /// #   #[allow(unused)] // prevents a "field `name` is never read" error
+    ///     name: &'static str, // ignored by equality and ordering operations
+    /// }
+    ///
+    /// impl PartialEq for S {
+    ///     fn eq(&self, other: &S) -> bool {
+    ///         self.id == other.id
+    ///     }
+    /// }
+    ///
+    /// impl Eq for S {}
+    ///
+    /// impl PartialOrd for S {
+    ///     fn partial_cmp(&self, other: &S) -> Option<Ordering> {
+    ///         self.id.partial_cmp(&other.id)
+    ///     }
+    /// }
+    ///
+    /// impl Ord for S {
+    ///     fn cmp(&self, other: &S) -> Ordering {
+    ///         self.id.cmp(&other.id)
+    ///     }
+    /// }
+    ///
+    /// let j_a = S { id: 1, name: "Jessica" };
+    /// let j_b = S { id: 1, name: "Jess" };
+    /// let p = S { id: 2, name: "Paul" };
+    /// assert_eq!(j_a, j_b);
+    ///
     /// let mut map = BTreeMap::new();
-    /// map.insert(1, "a");
-    /// assert_eq!(map.get_key_value(&1), Some((&1, &"a")));
-    /// assert_eq!(map.get_key_value(&2), None);
+    /// map.insert(j_a, "Paris");
+    /// assert_eq!(map.get_key_value(&j_a), Some((&j_a, &"Paris")));
+    /// assert_eq!(map.get_key_value(&j_b), Some((&j_a, &"Paris"))); // the notable case
+    /// assert_eq!(map.get_key_value(&p), None);
     /// ```
     #[stable(feature = "map_get_key_value", since = "1.40.0")]
     pub fn get_key_value<Q: ?Sized>(&self, k: &Q) -> Option<(&K, &V)>

library/core/src/panic.rs

@@ -215,7 +215,7 @@ pub macro const_panic {
                 #[noinline]
                 if const #[track_caller] #[inline] { // Inline this, to prevent codegen
                     $crate::panic!($const_msg)
-                } else #[track_caller] { // Do not inline this, it makes perf worse
+                } else #[track_caller] #[cfg_attr(bootstrap, inline)] { // Do not inline this, it makes perf worse
                     $crate::panic!($runtime_msg)
                 }
             )

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

@@ -880,7 +880,11 @@ where
         self.base.get(k)
     }
 
-    /// Returns the key-value pair corresponding to the supplied key.
+    /// Returns the key-value pair corresponding to the supplied key. This is
+    /// potentially useful:
+    /// - for key types where non-identical keys can be considered equal;
+    /// - for getting the `&K` stored key value from a borrowed `&Q` lookup key; or
+    /// - for getting a reference to a key with the same lifetime as the collection.
     ///
     /// The supplied key may be any borrowed form of the map's key type, but
     /// [`Hash`] and [`Eq`] on the borrowed form *must* match those for
@@ -890,11 +894,39 @@ where
     ///
     /// ```
     /// use std::collections::HashMap;
+    /// use std::hash::{Hash, Hasher};
+    ///
+    /// #[derive(Clone, Copy, Debug)]
+    /// struct S {
+    ///     id: u32,
+    /// #   #[allow(unused)] // prevents a "field `name` is never read" error
+    ///     name: &'static str, // ignored by equality and hashing operations
+    /// }
+    ///
+    /// impl PartialEq for S {
+    ///     fn eq(&self, other: &S) -> bool {
+    ///         self.id == other.id
+    ///     }
+    /// }
+    ///
+    /// impl Eq for S {}
+    ///
+    /// impl Hash for S {
+    ///     fn hash<H: Hasher>(&self, state: &mut H) {
+    ///         self.id.hash(state);
+    ///     }
+    /// }
+    ///
+    /// let j_a = S { id: 1, name: "Jessica" };
+    /// let j_b = S { id: 1, name: "Jess" };
+    /// let p = S { id: 2, name: "Paul" };
+    /// assert_eq!(j_a, j_b);
     ///
     /// let mut map = HashMap::new();
-    /// map.insert(1, "a");
-    /// assert_eq!(map.get_key_value(&1), Some((&1, &"a")));
-    /// assert_eq!(map.get_key_value(&2), None);
+    /// map.insert(j_a, "Paris");
+    /// assert_eq!(map.get_key_value(&j_a), Some((&j_a, &"Paris")));
+    /// assert_eq!(map.get_key_value(&j_b), Some((&j_a, &"Paris"))); // the notable case
+    /// assert_eq!(map.get_key_value(&p), None);
     /// ```
     #[inline]
     #[stable(feature = "map_get_key_value", since = "1.40.0")]