Auto merge of #89530 - workingjubilee:rollup-ua14iq6, r=workingjubilee

Rollup of 13 pull requests

Successful merges:

 - #83655 ([aarch64] add target feature outline-atomics)
 - #87091 (implement advance_(back_)_by on more iterators)
 - #88451 (Fix an ICE caused by type mismatch errors being ignored)
 - #88452 (VecDeque: improve performance for From<[T; N]>)
 - #89400 (Improve wording of `map_or_else` docs)
 - #89407 (Recommend running `cargo clean` in E0514 output)
 - #89443 (Include the length in BTree hashes)
 - #89444 (rustdoc: use slice::contains instead of open-coding it)
 - #89447 (Improve error message for missing angle brackets in `[_]::method`)
 - #89453 (Consistently use 'supertrait'.)
 - #89483 (Practice diagnostic message convention)
 - #89500 (Fix ICE with buffered lint referring to AST node deleted by everybody_loops)
 - #89508 (Stabilize `const_panic`)

Failed merges:

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

Author: bors

compiler/rustc_ast/src/ast.rs

@@ -1211,6 +1211,8 @@ impl Expr {
                 }
             }
 
+            ExprKind::Underscore => TyKind::Infer,
+
             // This expression doesn't look like a type syntactically.
             _ => return None,
         };

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -590,7 +590,7 @@ impl<'a> AstValidator<'a> {
                 )
                 .span_label(self.current_extern_span(), "in this `extern` block")
                 .note(&format!(
-                    "This limitation may be lifted in the future; see issue #{} <https://github.com/rust-lang/rust/issues/{}> for more information",
+                    "this limitation may be lifted in the future; see issue #{} <https://github.com/rust-lang/rust/issues/{}> for more information",
                     n, n,
                 ))
                 .emit();