Auto merge of #80364 - Dylan-DPC:rollup-0y96okz, r=Dylan-DPC

Rollup of 11 pull requests

Successful merges:

 - #79213 (Stabilize `core::slice::fill`)
 - #79999 (Refactored verbose print into a function)
 - #80160 (Implemented a compiler diagnostic for move async mistake)
 - #80274 (Rename rustc_middle::lint::LintSource)
 - #80280 (Add installation commands to `x` tool README)
 - #80319 (Fix elided lifetimes shown as `'_` on async functions)
 - #80327 (Updated the match with the matches macro)
 - #80330 (Fix typo in simplify_try.rs)
 - #80340 (Don't unnecessarily override attrs for Module)
 - #80342 (Fix typo)
 - #80352 (BTreeMap: make test cases more explicit on failure)

Failed merges:

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

compiler/rustc_lint/src/levels.rs

@@ -12,7 +12,9 @@ use rustc_hir::{intravisit, HirId};
 use rustc_middle::hir::map::Map;
 use rustc_middle::lint::LevelSource;
 use rustc_middle::lint::LintDiagnosticBuilder;
-use rustc_middle::lint::{struct_lint_level, LintLevelMap, LintLevelSets, LintSet, LintSource};
+use rustc_middle::lint::{
+    struct_lint_level, LintLevelMap, LintLevelSets, LintLevelSource, LintSet,
+};
 use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::TyCtxt;
 use rustc_session::lint::{builtin, Level, Lint, LintId};
@@ -91,7 +93,7 @@ impl<'s> LintLevelsBuilder<'s> {
             };
             for id in ids {
                 self.check_gated_lint(id, DUMMY_SP);
-                let src = LintSource::CommandLine(lint_flag_val, orig_level);
+                let src = LintLevelSource::CommandLine(lint_flag_val, orig_level);
                 specs.insert(id, (level, src));
             }
         }
@@ -128,19 +130,19 @@ impl<'s> LintLevelsBuilder<'s> {
                 );
                 diag_builder.span_label(src.span(), "overruled by previous forbid");
                 match old_src {
-                    LintSource::Default => {
+                    LintLevelSource::Default => {
                         diag_builder.note(&format!(
                             "`forbid` lint level is the default for {}",
                             id.to_string()
                         ));
                     }
-                    LintSource::Node(_, forbid_source_span, reason) => {
+                    LintLevelSource::Node(_, forbid_source_span, reason) => {
                         diag_builder.span_label(forbid_source_span, "`forbid` level set here");
                         if let Some(rationale) = reason {
                             diag_builder.note(&rationale.as_str());
                         }
                     }
-                    LintSource::CommandLine(_, _) => {
+                    LintLevelSource::CommandLine(_, _) => {
                         diag_builder.note("`forbid` lint level was set on command line");
                     }
                 }
@@ -276,7 +278,7 @@ impl<'s> LintLevelsBuilder<'s> {
                 let name = meta_item.path.segments.last().expect("empty lint name").ident.name;
                 match store.check_lint_name(&name.as_str(), tool_name) {
                     CheckLintNameResult::Ok(ids) => {
-                        let src = LintSource::Node(name, li.span(), reason);
+                        let src = LintLevelSource::Node(name, li.span(), reason);
                         for &id in ids {
                             self.check_gated_lint(id, attr.span);
                             self.insert_spec(&mut specs, id, (level, src));
@@ -287,7 +289,7 @@ impl<'s> LintLevelsBuilder<'s> {
                         match result {
                             Ok(ids) => {
                                 let complete_name = &format!("{}::{}", tool_name.unwrap(), name);
-                                let src = LintSource::Node(
+                                let src = LintLevelSource::Node(
                                     Symbol::intern(complete_name),
                                     li.span(),
                                     reason,
@@ -324,7 +326,7 @@ impl<'s> LintLevelsBuilder<'s> {
                                     },
                                 );
 
-                                let src = LintSource::Node(
+                                let src = LintLevelSource::Node(
                                     Symbol::intern(&new_lint_name),
                                     li.span(),
                                     reason,
@@ -403,7 +405,7 @@ impl<'s> LintLevelsBuilder<'s> {
                 }
 
                 let (lint_attr_name, lint_attr_span) = match *src {
-                    LintSource::Node(name, span, _) => (name, span),
+                    LintLevelSource::Node(name, span, _) => (name, span),
                     _ => continue,
                 };
 
@@ -460,7 +462,7 @@ impl<'s> LintLevelsBuilder<'s> {
     }
 
     /// Find the lint level for a lint.
-    pub fn lint_level(&self, lint: &'static Lint) -> (Level, LintSource) {
+    pub fn lint_level(&self, lint: &'static Lint) -> (Level, LintLevelSource) {
         self.sets.get_lint_level(lint, self.cur, None, self.sess)
     }
 

compiler/rustc_middle/src/lint.rs

@@ -13,7 +13,7 @@ use rustc_span::{symbol, Span, Symbol, DUMMY_SP};
 
 /// How a lint level was set.
 #[derive(Clone, Copy, PartialEq, Eq, HashStable)]
-pub enum LintSource {
+pub enum LintLevelSource {
     /// Lint is at the default level as declared
     /// in rustc or a plugin.
     Default,
@@ -27,25 +27,26 @@ pub enum LintSource {
     CommandLine(Symbol, Level),
 }
 
-impl LintSource {
+impl LintLevelSource {
     pub fn name(&self) -> Symbol {
         match *self {
-            LintSource::Default => symbol::kw::Default,
+            LintLevelSource::Default => symbol::kw::Default,
-            LintSource::Node(name, _, _) => name,
+            LintLevelSource::Node(name, _, _) => name,
-            LintSource::CommandLine(name, _) => name,
+            LintLevelSource::CommandLine(name, _) => name,
         }
     }
 
     pub fn span(&self) -> Span {
         match *self {
-            LintSource::Default => DUMMY_SP,
+            LintLevelSource::Default => DUMMY_SP,
-            LintSource::Node(_, span, _) => span,
+            LintLevelSource::Node(_, span, _) => span,
-            LintSource::CommandLine(_, _) => DUMMY_SP,
+            LintLevelSource::CommandLine(_, _) => DUMMY_SP,
         }
     }
 }
 
-pub type LevelSource = (Level, LintSource);
+/// A tuple of a lint level and its source.
+pub type LevelSource = (Level, LintLevelSource);
 
 pub struct LintLevelSets {
     pub list: Vec<LintSet>,
@@ -113,7 +114,7 @@ impl LintLevelSets {
         id: LintId,
         mut idx: u32,
         aux: Option<&FxHashMap<LintId, LevelSource>>,
-    ) -> (Option<Level>, LintSource) {
+    ) -> (Option<Level>, LintLevelSource) {
         if let Some(specs) = aux {
             if let Some(&(level, src)) = specs.get(&id) {
                 return (Some(level), src);
@@ -125,7 +126,7 @@ impl LintLevelSets {
                     if let Some(&(level, src)) = specs.get(&id) {
                         return (Some(level), src);
                     }
-                    return (None, LintSource::Default);
+                    return (None, LintLevelSource::Default);
                 }
                 LintSet::Node { ref specs, parent } => {
                     if let Some(&(level, src)) = specs.get(&id) {
@@ -213,7 +214,7 @@ pub fn struct_lint_level<'s, 'd>(
     sess: &'s Session,
     lint: &'static Lint,
     level: Level,
-    src: LintSource,
+    src: LintLevelSource,
     span: Option<MultiSpan>,
     decorate: impl for<'a> FnOnce(LintDiagnosticBuilder<'a>) + 'd,
 ) {
@@ -223,7 +224,7 @@ pub fn struct_lint_level<'s, 'd>(
         sess: &'s Session,
         lint: &'static Lint,
         level: Level,
-        src: LintSource,
+        src: LintLevelSource,
         span: Option<MultiSpan>,
         decorate: Box<dyn for<'b> FnOnce(LintDiagnosticBuilder<'b>) + 'd>,
     ) {
@@ -274,14 +275,14 @@ pub fn struct_lint_level<'s, 'd>(
 
         let name = lint.name_lower();
         match src {
-            LintSource::Default => {
+            LintLevelSource::Default => {
                 sess.diag_note_once(
                     &mut err,
                     DiagnosticMessageId::from(lint),
                     &format!("`#[{}({})]` on by default", level.as_str(), name),
                 );
             }
-            LintSource::CommandLine(lint_flag_val, orig_level) => {
+            LintLevelSource::CommandLine(lint_flag_val, orig_level) => {
                 let flag = match orig_level {
                     Level::Warn => "-W",
                     Level::Deny => "-D",
@@ -310,7 +311,7 @@ pub fn struct_lint_level<'s, 'd>(
                     );
                 }
             }
-            LintSource::Node(lint_attr_name, src, reason) => {
+            LintLevelSource::Node(lint_attr_name, src, reason) => {
                 if let Some(rationale) = reason {
                     err.note(&rationale.as_str());
                 }

compiler/rustc_middle/src/ty/context.rs

@@ -5,7 +5,7 @@ use crate::dep_graph::{self, DepGraph, DepKind, DepNode, DepNodeExt};
 use crate::hir::exports::ExportMap;
 use crate::ich::{NodeIdHashingMode, StableHashingContext};
 use crate::infer::canonical::{Canonical, CanonicalVarInfo, CanonicalVarInfos};
-use crate::lint::{struct_lint_level, LintDiagnosticBuilder, LintSource};
+use crate::lint::{struct_lint_level, LintDiagnosticBuilder, LintLevelSource};
 use crate::middle;
 use crate::middle::cstore::{CrateStoreDyn, EncodedMetadata};
 use crate::middle::resolve_lifetime::{self, ObjectLifetimeDefault};
@@ -2559,7 +2559,7 @@ impl<'tcx> TyCtxt<'tcx> {
         self,
         lint: &'static Lint,
         mut id: hir::HirId,
-    ) -> (Level, LintSource) {
+    ) -> (Level, LintLevelSource) {
         let sets = self.lint_levels(LOCAL_CRATE);
         loop {
             if let Some(pair) = sets.level_and_source(lint, id, self.sess) {

compiler/rustc_middle/src/ty/list.rs

@@ -24,7 +24,7 @@ extern "C" {
 /// This means we can use pointer for both
 /// equality comparisons and hashing.
 ///
-/// Unlike slices, The types contained in `List` are expected to be `Copy`
+/// Unlike slices, the types contained in `List` are expected to be `Copy`
 /// and iterating over a `List` returns `T` instead of a reference.
 ///
 /// Note: `Slice` was already taken by the `Ty`.

compiler/rustc_middle/src/ty/sty.rs

@@ -215,10 +215,7 @@ pub enum TyKind<'tcx> {
 impl TyKind<'tcx> {
     #[inline]
     pub fn is_primitive(&self) -> bool {
-        match self {
+        matches!(self, Bool | Char | Int(_) | Uint(_) | Float(_))
-            Bool | Char | Int(_) | Uint(_) | Float(_) => true,
-            _ => false,
-        }
     }
 
     /// Get the article ("a" or "an") to use with this type.

compiler/rustc_mir/src/transform/simplify_try.rs

@@ -306,7 +306,7 @@ fn optimization_applies<'tcx>(
         return false;
     }
 
-    // Verify the assigment chain consists of the form b = a; c = b; d = c; etc...
+    // Verify the assignment chain consists of the form b = a; c = b; d = c; etc...
     if opt_info.field_tmp_assignments.is_empty() {
         trace!("NO: no assignments found");
         return false;

compiler/rustc_mir/src/util/pretty.rs

@@ -17,7 +17,7 @@ use rustc_middle::mir::interpret::{
 };
 use rustc_middle::mir::visit::Visitor;
 use rustc_middle::mir::*;
-use rustc_middle::ty::{self, TyCtxt, TypeFoldable, TypeVisitor};
+use rustc_middle::ty::{self, TyCtxt, TyS, TypeFoldable, TypeVisitor};
 use rustc_target::abi::Size;
 use std::ops::ControlFlow;
 
@@ -408,6 +408,18 @@ impl ExtraComments<'tcx> {
     }
 }
 
+fn use_verbose(ty: &&TyS<'tcx>) -> bool {
+    match ty.kind() {
+        ty::Int(_) | ty::Uint(_) | ty::Bool | ty::Char | ty::Float(_) => false,
+        // Unit type
+        ty::Tuple(g_args) if g_args.is_empty() => false,
+        ty::Tuple(g_args) => g_args.iter().any(|g_arg| use_verbose(&g_arg.expect_ty())),
+        ty::Array(ty, _) => use_verbose(ty),
+        ty::FnDef(..) => false,
+        _ => true,
+    }
+}
+
 impl Visitor<'tcx> for ExtraComments<'tcx> {
     fn visit_constant(&mut self, constant: &Constant<'tcx>, location: Location) {
         self.super_constant(constant, location);
@@ -430,16 +442,10 @@ impl Visitor<'tcx> for ExtraComments<'tcx> {
     fn visit_const(&mut self, constant: &&'tcx ty::Const<'tcx>, _: Location) {
         self.super_const(constant);
         let ty::Const { ty, val, .. } = constant;
-        match ty.kind() {
+        if use_verbose(ty) {
-            ty::Int(_) | ty::Uint(_) | ty::Bool | ty::Char | ty::Float(_) => {}
+            self.push("ty::Const");
-            // Unit type
+            self.push(&format!("+ ty: {:?}", ty));
-            ty::Tuple(tys) if tys.is_empty() => {}
+            self.push(&format!("+ val: {:?}", val));
-            ty::FnDef(..) => {}
-            _ => {
-                self.push("ty::Const");
-                self.push(&format!("+ ty: {:?}", ty));
-                self.push(&format!("+ val: {:?}", val));
-            }
         }
     }
 

compiler/rustc_parse/src/parser/diagnostics.rs

@@ -1912,4 +1912,22 @@ impl<'a> Parser<'a> {
         *self = snapshot;
         Err(err)
     }
+
+    /// Get the diagnostics for the cases where `move async` is found.
+    ///
+    /// `move_async_span` starts at the 'm' of the move keyword and ends with the 'c' of the async keyword
+    pub(super) fn incorrect_move_async_order_found(
+        &self,
+        move_async_span: Span,
+    ) -> DiagnosticBuilder<'a> {
+        let mut err =
+            self.struct_span_err(move_async_span, "the order of `move` and `async` is incorrect");
+        err.span_suggestion_verbose(
+            move_async_span,
+            "try switching the order",
+            "async move".to_owned(),
+            Applicability::MaybeIncorrect,
+        );
+        err
+    }
 }

compiler/rustc_parse/src/parser/expr.rs

@@ -1603,7 +1603,7 @@ impl<'a> Parser<'a> {
             self.sess.gated_spans.gate(sym::async_closure, span);
         }
 
-        let capture_clause = self.parse_capture_clause();
+        let capture_clause = self.parse_capture_clause()?;
         let decl = self.parse_fn_block_decl()?;
         let decl_hi = self.prev_token.span;
         let body = match decl.output {
@@ -1626,8 +1626,18 @@ impl<'a> Parser<'a> {
     }
 
     /// Parses an optional `move` prefix to a closure-like construct.
-    fn parse_capture_clause(&mut self) -> CaptureBy {
+    fn parse_capture_clause(&mut self) -> PResult<'a, CaptureBy> {
-        if self.eat_keyword(kw::Move) { CaptureBy::Value } else { CaptureBy::Ref }
+        if self.eat_keyword(kw::Move) {
+            // Check for `move async` and recover
+            if self.check_keyword(kw::Async) {
+                let move_async_span = self.token.span.with_lo(self.prev_token.span.data().lo);
+                Err(self.incorrect_move_async_order_found(move_async_span))
+            } else {
+                Ok(CaptureBy::Value)
+            }
+        } else {
+            Ok(CaptureBy::Ref)
+        }
     }
 
     /// Parses the `|arg, arg|` header of a closure.
@@ -2019,7 +2029,7 @@ impl<'a> Parser<'a> {
     fn parse_async_block(&mut self, mut attrs: AttrVec) -> PResult<'a, P<Expr>> {
         let lo = self.token.span;
         self.expect_keyword(kw::Async)?;
-        let capture_clause = self.parse_capture_clause();
+        let capture_clause = self.parse_capture_clause()?;
         let (iattrs, body) = self.parse_inner_attrs_and_block()?;
         attrs.extend(iattrs);
         let kind = ExprKind::Async(capture_clause, DUMMY_NODE_ID, body);

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

@@ -115,7 +115,7 @@ impl<K, V> BTreeMap<K, V> {
 
 impl<'a, K: 'a, V: 'a> NodeRef<marker::Immut<'a>, K, V, marker::LeafOrInternal> {
     fn assert_min_len(self, min_len: usize) {
-        assert!(self.len() >= min_len, "{} < {}", self.len(), min_len);
+        assert!(self.len() >= min_len, "node len {} < {}", self.len(), min_len);
         if let node::ForceResult::Internal(node) = self.force() {
             for idx in 0..=node.len() {
                 let edge = unsafe { Handle::new_edge(node, idx) };

library/alloc/src/collections/btree/node/tests.rs

@@ -30,11 +30,15 @@ impl<'a, K: 'a, V: 'a> NodeRef<marker::Immut<'a>, K, V, marker::LeafOrInternal>
                 let depth = self.height();
                 let indent = "  ".repeat(depth);
                 result += &format!("\n{}", indent);
-                for idx in 0..leaf.len() {
+                if leaf.len() == 0 {
-                    if idx > 0 {
+                    result += "(empty node)";
-                        result += ", ";
+                } else {
+                    for idx in 0..leaf.len() {
+                        if idx > 0 {
+                            result += ", ";
+                        }
+                        result += &format!("{:?}", unsafe { leaf.key_at(idx) });
                     }
-                    result += &format!("{:?}", unsafe { leaf.key_at(idx) });
                 }
             }
             navigate::Position::Internal(_) => {}

library/core/src/slice/mod.rs

@@ -2581,14 +2581,12 @@ impl<T> [T] {
     /// # Examples
     ///
     /// ```
-    /// #![feature(slice_fill)]
-    ///
     /// let mut buf = vec![0; 10];
     /// buf.fill(1);
     /// assert_eq!(buf, vec![1; 10]);
     /// ```
     #[doc(alias = "memset")]
-    #[unstable(feature = "slice_fill", issue = "70758")]
+    #[stable(feature = "slice_fill", since = "1.50.0")]
     pub fn fill(&mut self, value: T)
     where
         T: Clone,

library/std/src/lib.rs

@@ -304,7 +304,6 @@
 #![feature(rustc_private)]
 #![feature(shrink_to)]
 #![feature(slice_concat_ext)]
-#![feature(slice_fill)]
 #![feature(slice_internals)]
 #![feature(slice_ptr_get)]
 #![feature(slice_ptr_len)]

src/librustdoc/clean/mod.rs

@@ -218,11 +218,6 @@ impl Clean<ExternalCrate> for CrateNum {
 
 impl Clean<Item> for doctree::Module<'_> {
     fn clean(&self, cx: &DocContext<'_>) -> Item {
-        // maintain a stack of mod ids, for doc comment path resolution
-        // but we also need to resolve the module's own docs based on whether its docs were written
-        // inside or outside the module, so check for that
-        let attrs = self.attrs.clean(cx);
-
         let mut items: Vec<Item> = vec![];
         items.extend(self.imports.iter().flat_map(|x| x.clean(cx)));
         items.extend(self.foreigns.iter().map(|x| x.clean(cx)));
@@ -251,7 +246,7 @@ impl Clean<Item> for doctree::Module<'_> {
             ModuleItem(Module { is_crate: self.is_crate, items }),
             cx,
         );
-        Item { attrs, source: span.clean(cx), ..what_rustc_thinks }
+        Item { source: span.clean(cx), ..what_rustc_thinks }
     }
 }
 
@@ -638,6 +633,18 @@ impl Clean<Generics> for hir::Generics<'_> {
                 _ => false,
             }
         }
+        /// This can happen for `async fn`, e.g. `async fn f<'_>(&'_ self)`.
+        ///
+        /// See [`lifetime_to_generic_param`] in [`rustc_ast_lowering`] for more information.
+        ///
+        /// [`lifetime_to_generic_param`]: rustc_ast_lowering::LoweringContext::lifetime_to_generic_param
+        fn is_elided_lifetime(param: &hir::GenericParam<'_>) -> bool {
+            match param.kind {
+                hir::GenericParamKind::Lifetime { kind: hir::LifetimeParamKind::Elided } => true,
+                _ => false,
+            }
+        }
+
         let impl_trait_params = self
             .params
             .iter()
@@ -656,7 +663,7 @@ impl Clean<Generics> for hir::Generics<'_> {
             .collect::<Vec<_>>();
 
         let mut params = Vec::with_capacity(self.params.len());
-        for p in self.params.iter().filter(|p| !is_impl_trait(p)) {
+        for p in self.params.iter().filter(|p| !is_impl_trait(p) && !is_elided_lifetime(p)) {
             let p = p.clean(cx);
             params.push(p);
         }
@@ -1437,7 +1444,16 @@ impl Clean<Type> for hir::Ty<'_> {
             TyKind::Never => Never,
             TyKind::Ptr(ref m) => RawPointer(m.mutbl, box m.ty.clean(cx)),
             TyKind::Rptr(ref l, ref m) => {
-                let lifetime = if l.is_elided() { None } else { Some(l.clean(cx)) };
+                // There are two times a `Fresh` lifetime can be created:
+                // 1. For `&'_ x`, written by the user. This corresponds to `lower_lifetime` in `rustc_ast_lowering`.
+                // 2. For `&x` as a parameter to an `async fn`. This corresponds to `elided_ref_lifetime in `rustc_ast_lowering`.
+                //    See #59286 for more information.
+                // Ideally we would only hide the `'_` for case 2., but I don't know a way to distinguish it.
+                // Turning `fn f(&'_ self)` into `fn f(&self)` isn't the worst thing in the world, though;
+                // there's no case where it could cause the function to fail to compile.
+                let elided =
+                    l.is_elided() || matches!(l.name, LifetimeName::Param(ParamName::Fresh(_)));
+                let lifetime = if elided { None } else { Some(l.clean(cx)) };
                 BorrowedRef { lifetime, mutability: m.mutbl, type_: box m.ty.clean(cx) }
             }
             TyKind::Slice(ref ty) => Slice(box ty.clean(cx)),

src/librustdoc/doctree.rs

@@ -9,7 +9,6 @@ use rustc_hir as hir;
 
 crate struct Module<'hir> {
     crate name: Option<Symbol>,
-    crate attrs: &'hir [ast::Attribute],
     crate where_outer: Span,
     crate where_inner: Span,
     crate imports: Vec<Import<'hir>>,
@@ -23,13 +22,12 @@ crate struct Module<'hir> {
 }
 
 impl Module<'hir> {
-    crate fn new(name: Option<Symbol>, attrs: &'hir [ast::Attribute]) -> Module<'hir> {
+    crate fn new(name: Option<Symbol>) -> Module<'hir> {
         Module {
             name,
             id: hir::CRATE_HIR_ID,
             where_outer: rustc_span::DUMMY_SP,
             where_inner: rustc_span::DUMMY_SP,
-            attrs,
             imports: Vec::new(),
             mods: Vec::new(),
             items: Vec::new(),

src/librustdoc/passes/calculate_doc_coverage.rs

@@ -5,7 +5,7 @@ use crate::html::markdown::{find_testable_code, ErrorCodes};
 use crate::passes::doc_test_lints::{should_have_doc_example, Tests};
 use crate::passes::Pass;
 use rustc_lint::builtin::MISSING_DOCS;
-use rustc_middle::lint::LintSource;
+use rustc_middle::lint::LintLevelSource;
 use rustc_session::lint;
 use rustc_span::symbol::sym;
 use rustc_span::FileName;
@@ -254,7 +254,7 @@ impl<'a, 'b> fold::DocFolder for CoverageCalculator<'a, 'b> {
                 // `missing_docs` is allow-by-default, so don't treat this as ignoring the item
                 // unless the user had an explicit `allow`
                 let should_have_docs =
-                    level != lint::Level::Allow || matches!(source, LintSource::Default);
+                    level != lint::Level::Allow || matches!(source, LintLevelSource::Default);
                 debug!("counting {:?} {:?} in {}", i.type_(), i.name, filename);
                 self.items.entry(filename).or_default().count_item(
                     has_docs,

src/librustdoc/passes/doc_test_lints.rs

@@ -9,7 +9,7 @@ use crate::clean::*;
 use crate::core::DocContext;
 use crate::fold::DocFolder;
 use crate::html::markdown::{find_testable_code, ErrorCodes, Ignore, LangString};
-use rustc_middle::lint::LintSource;
+use rustc_middle::lint::LintLevelSource;
 use rustc_session::lint;
 
 crate const CHECK_PRIVATE_ITEMS_DOC_TESTS: Pass = Pass {
@@ -77,7 +77,7 @@ crate fn should_have_doc_example(cx: &DocContext<'_>, item: &clean::Item) -> boo
     let hir_id = cx.tcx.hir().local_def_id_to_hir_id(item.def_id.expect_local());
     let (level, source) =
         cx.tcx.lint_level_at_node(lint::builtin::MISSING_DOC_CODE_EXAMPLES, hir_id);
-    level != lint::Level::Allow || matches!(source, LintSource::Default)
+    level != lint::Level::Allow || matches!(source, LintLevelSource::Default)
 }
 
 crate fn look_for_tests<'tcx>(cx: &DocContext<'tcx>, dox: &str, item: &Item) {

src/librustdoc/visit_ast.rs

@@ -1,7 +1,6 @@
 //! The Rust AST Visitor. Extracts useful information and massages it into a form
 //! usable for `clean`.
 
-use rustc_ast as ast;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, Res};
@@ -64,7 +63,6 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
     crate fn visit(mut self, krate: &'tcx hir::Crate<'_>) -> Module<'tcx> {
         let mut module = self.visit_mod_contents(
             krate.item.span,
-            krate.item.attrs,
             &Spanned { span: rustc_span::DUMMY_SP, node: hir::VisibilityKind::Public },
             hir::CRATE_HIR_ID,
             &krate.item.module,
@@ -82,13 +80,12 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
     fn visit_mod_contents(
         &mut self,
         span: Span,
-        attrs: &'tcx [ast::Attribute],
         vis: &'tcx hir::Visibility<'_>,
         id: hir::HirId,
         m: &'tcx hir::Mod<'tcx>,
         name: Option<Symbol>,
     ) -> Module<'tcx> {
-        let mut om = Module::new(name, attrs);
+        let mut om = Module::new(name);
         om.where_outer = span;
         om.where_inner = m.inner;
         om.id = id;
@@ -292,7 +289,6 @@ impl<'a, 'tcx> RustdocVisitor<'a, 'tcx> {
             hir::ItemKind::Mod(ref m) => {
                 om.mods.push(self.visit_mod_contents(
                     item.span,
-                    &item.attrs,
                     &item.vis,
                     item.hir_id,
                     m,

src/test/mir-opt/const_prop/checked_add.main.ConstProp.diff

@@ -14,9 +14,6 @@
 -         _2 = CheckedAdd(const 1_u32, const 1_u32); // scope 0 at $DIR/checked_add.rs:5:18: 5:23
 -         assert(!move (_2.1: bool), "attempt to compute `{} + {}`, which would overflow", const 1_u32, const 1_u32) -> bb1; // scope 0 at $DIR/checked_add.rs:5:18: 5:23
 +         _2 = const (2_u32, false);       // scope 0 at $DIR/checked_add.rs:5:18: 5:23
-+                                          // ty::Const
-+                                          // + ty: (u32, bool)
-+                                          // + val: Value(ByRef { alloc: Allocation { bytes: [2, 0, 0, 0, 0, 0, 0, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [31], len: Size { raw: 8 } }, size: Size { raw: 8 }, align: Align { pow2: 2 }, mutability: Not, extra: () }, offset: Size { raw: 0 } })
 +                                          // mir::Constant
 +                                          // + span: $DIR/checked_add.rs:5:18: 5:23
 +                                          // + literal: Const { ty: (u32, bool), val: Value(ByRef { alloc: Allocation { bytes: [2, 0, 0, 0, 0, 0, 0, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [31], len: Size { raw: 8 } }, size: Size { raw: 8 }, align: Align { pow2: 2 }, mutability: Not, extra: () }, offset: Size { raw: 0 } }) }

src/test/mir-opt/const_prop/indirect.main.ConstProp.diff

@@ -18,9 +18,6 @@
 -         assert(!move (_3.1: bool), "attempt to compute `{} + {}`, which would overflow", move _2, const 1_u8) -> bb1; // scope 0 at $DIR/indirect.rs:5:13: 5:29
 +         _2 = const 2_u8;                 // scope 0 at $DIR/indirect.rs:5:13: 5:25
 +         _3 = const (3_u8, false);        // scope 0 at $DIR/indirect.rs:5:13: 5:29
-+                                          // ty::Const
-+                                          // + ty: (u8, bool)
-+                                          // + val: Value(ByRef { alloc: Allocation { bytes: [3, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [3], len: Size { raw: 2 } }, size: Size { raw: 2 }, align: Align { pow2: 0 }, mutability: Not, extra: () }, offset: Size { raw: 0 } })
 +                                          // mir::Constant
 +                                          // + span: $DIR/indirect.rs:5:13: 5:29
 +                                          // + literal: Const { ty: (u8, bool), val: Value(ByRef { alloc: Allocation { bytes: [3, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [3], len: Size { raw: 2 } }, size: Size { raw: 2 }, align: Align { pow2: 0 }, mutability: Not, extra: () }, offset: Size { raw: 0 } }) }

src/test/mir-opt/const_prop/issue_67019.main.ConstProp.diff

@@ -15,9 +15,6 @@
           (_3.1: u8) = const 2_u8;         // scope 0 at $DIR/issue-67019.rs:11:11: 11:17
 -         (_2.0: (u8, u8)) = move _3;      // scope 0 at $DIR/issue-67019.rs:11:10: 11:19
 +         (_2.0: (u8, u8)) = const (1_u8, 2_u8); // scope 0 at $DIR/issue-67019.rs:11:10: 11:19
-+                                          // ty::Const
-+                                          // + ty: (u8, u8)
-+                                          // + val: Value(ByRef { alloc: Allocation { bytes: [1, 2], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [3], len: Size { raw: 2 } }, size: Size { raw: 2 }, align: Align { pow2: 0 }, mutability: Not, extra: () }, offset: Size { raw: 0 } })
 +                                          // mir::Constant
 +                                          // + span: $DIR/issue-67019.rs:11:10: 11:19
 +                                          // + literal: Const { ty: (u8, u8), val: Value(ByRef { alloc: Allocation { bytes: [1, 2], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [3], len: Size { raw: 2 } }, size: Size { raw: 2 }, align: Align { pow2: 0 }, mutability: Not, extra: () }, offset: Size { raw: 0 } }) }

src/test/mir-opt/const_prop/mutable_variable_aggregate.main.ConstProp.diff

@@ -20,9 +20,6 @@
           StorageLive(_2);                 // scope 1 at $DIR/mutable_variable_aggregate.rs:7:9: 7:10
 -         _2 = _1;                         // scope 1 at $DIR/mutable_variable_aggregate.rs:7:13: 7:14
 +         _2 = const (42_i32, 99_i32);     // scope 1 at $DIR/mutable_variable_aggregate.rs:7:13: 7:14
-+                                          // ty::Const
-+                                          // + ty: (i32, i32)
-+                                          // + val: Value(ByRef { alloc: Allocation { bytes: [42, 0, 0, 0, 99, 0, 0, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [255], len: Size { raw: 8 } }, size: Size { raw: 8 }, align: Align { pow2: 2 }, mutability: Not, extra: () }, offset: Size { raw: 0 } })
 +                                          // mir::Constant
 +                                          // + span: $DIR/mutable_variable_aggregate.rs:7:13: 7:14
 +                                          // + literal: Const { ty: (i32, i32), val: Value(ByRef { alloc: Allocation { bytes: [42, 0, 0, 0, 99, 0, 0, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [255], len: Size { raw: 8 } }, size: Size { raw: 8 }, align: Align { pow2: 2 }, mutability: Not, extra: () }, offset: Size { raw: 0 } }) }

src/test/mir-opt/const_prop/optimizes_into_variable.main.ConstProp.32bit.diff

@@ -27,9 +27,6 @@
 -         _2 = CheckedAdd(const 2_i32, const 2_i32); // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
 -         assert(!move (_2.1: bool), "attempt to compute `{} + {}`, which would overflow", const 2_i32, const 2_i32) -> bb1; // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
 +         _2 = const (4_i32, false);       // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
-+                                          // ty::Const
-+                                          // + ty: (i32, bool)
-+                                          // + val: Value(ByRef { alloc: Allocation { bytes: [4, 0, 0, 0, 0, 0, 0, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [31], len: Size { raw: 8 } }, size: Size { raw: 8 }, align: Align { pow2: 2 }, mutability: Not, extra: () }, offset: Size { raw: 0 } })
 +                                          // mir::Constant
 +                                          // + span: $DIR/optimizes_into_variable.rs:12:13: 12:18
 +                                          // + literal: Const { ty: (i32, bool), val: Value(ByRef { alloc: Allocation { bytes: [4, 0, 0, 0, 0, 0, 0, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [31], len: Size { raw: 8 } }, size: Size { raw: 8 }, align: Align { pow2: 2 }, mutability: Not, extra: () }, offset: Size { raw: 0 } }) }

src/test/mir-opt/const_prop/optimizes_into_variable.main.ConstProp.64bit.diff

@@ -27,9 +27,6 @@
 -         _2 = CheckedAdd(const 2_i32, const 2_i32); // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
 -         assert(!move (_2.1: bool), "attempt to compute `{} + {}`, which would overflow", const 2_i32, const 2_i32) -> bb1; // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
 +         _2 = const (4_i32, false);       // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
-+                                          // ty::Const
-+                                          // + ty: (i32, bool)
-+                                          // + val: Value(ByRef { alloc: Allocation { bytes: [4, 0, 0, 0, 0, 0, 0, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [31], len: Size { raw: 8 } }, size: Size { raw: 8 }, align: Align { pow2: 2 }, mutability: Not, extra: () }, offset: Size { raw: 0 } })
 +                                          // mir::Constant
 +                                          // + span: $DIR/optimizes_into_variable.rs:12:13: 12:18
 +                                          // + literal: Const { ty: (i32, bool), val: Value(ByRef { alloc: Allocation { bytes: [4, 0, 0, 0, 0, 0, 0, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [31], len: Size { raw: 8 } }, size: Size { raw: 8 }, align: Align { pow2: 2 }, mutability: Not, extra: () }, offset: Size { raw: 0 } }) }

src/test/mir-opt/const_prop/return_place.add.ConstProp.diff

@@ -9,9 +9,6 @@
 -         _1 = CheckedAdd(const 2_u32, const 2_u32); // scope 0 at $DIR/return_place.rs:6:5: 6:10
 -         assert(!move (_1.1: bool), "attempt to compute `{} + {}`, which would overflow", const 2_u32, const 2_u32) -> bb1; // scope 0 at $DIR/return_place.rs:6:5: 6:10
 +         _1 = const (4_u32, false);       // scope 0 at $DIR/return_place.rs:6:5: 6:10
-+                                          // ty::Const
-+                                          // + ty: (u32, bool)
-+                                          // + val: Value(ByRef { alloc: Allocation { bytes: [4, 0, 0, 0, 0, 0, 0, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [31], len: Size { raw: 8 } }, size: Size { raw: 8 }, align: Align { pow2: 2 }, mutability: Not, extra: () }, offset: Size { raw: 0 } })
 +                                          // mir::Constant
 +                                          // + span: $DIR/return_place.rs:6:5: 6:10
 +                                          // + literal: Const { ty: (u32, bool), val: Value(ByRef { alloc: Allocation { bytes: [4, 0, 0, 0, 0, 0, 0, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [31], len: Size { raw: 8 } }, size: Size { raw: 8 }, align: Align { pow2: 2 }, mutability: Not, extra: () }, offset: Size { raw: 0 } }) }

src/test/mir-opt/const_prop/tuple_literal_propagation.main.ConstProp.diff

@@ -18,9 +18,6 @@
           StorageLive(_3);                 // scope 1 at $DIR/tuple_literal_propagation.rs:5:13: 5:14
 -         _3 = _1;                         // scope 1 at $DIR/tuple_literal_propagation.rs:5:13: 5:14
 +         _3 = const (1_u32, 2_u32);       // scope 1 at $DIR/tuple_literal_propagation.rs:5:13: 5:14
-+                                          // ty::Const
-+                                          // + ty: (u32, u32)
-+                                          // + val: Value(ByRef { alloc: Allocation { bytes: [1, 0, 0, 0, 2, 0, 0, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [255], len: Size { raw: 8 } }, size: Size { raw: 8 }, align: Align { pow2: 2 }, mutability: Not, extra: () }, offset: Size { raw: 0 } })
 +                                          // mir::Constant
 +                                          // + span: $DIR/tuple_literal_propagation.rs:5:13: 5:14
 +                                          // + literal: Const { ty: (u32, u32), val: Value(ByRef { alloc: Allocation { bytes: [1, 0, 0, 0, 2, 0, 0, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [255], len: Size { raw: 8 } }, size: Size { raw: 8 }, align: Align { pow2: 2 }, mutability: Not, extra: () }, offset: Size { raw: 0 } }) }

src/test/mir-opt/simplify_locals_removes_unused_consts.main.SimplifyLocals.diff

@@ -42,9 +42,6 @@
                                            // mir::Constant
                                            // + span: $DIR/simplify-locals-removes-unused-consts.rs:14:5: 14:12
                                            // + literal: Const { ty: fn(((), ())) {use_zst}, val: Value(Scalar(<ZST>)) }
-                                           // ty::Const
-                                           // + ty: ((), ())
-                                           // + val: Value(Scalar(<ZST>))
                                            // mir::Constant
                                            // + span: $DIR/simplify-locals-removes-unused-consts.rs:14:5: 14:22
                                            // + literal: Const { ty: ((), ()), val: Value(Scalar(<ZST>)) }

src/test/rustdoc/async-fn.rs

@@ -1,3 +1,4 @@
+// ignore-tidy-linelength
 // edition:2018
 #![feature(min_const_generics)]
 
@@ -48,7 +49,50 @@ impl Foo {
     pub async fn mut_self(mut self, mut first: usize) {}
 }
 
+pub trait Pattern<'a> {}
+
 pub trait Trait<const N: usize> {}
 // @has async_fn/fn.const_generics.html
 // @has - '//pre[@class="rust fn"]' 'pub async fn const_generics<const N: usize>(_: impl Trait<N>)'
 pub async fn const_generics<const N: usize>(_: impl Trait<N>) {}
+
+// test that elided lifetimes are properly elided and not displayed as `'_`
+// regression test for #63037
+// @has async_fn/fn.elided.html
+// @has - '//pre[@class="rust fn"]' 'pub async fn elided(foo: &str) -> &str'
+pub async fn elided(foo: &str) -> &str {}
+// This should really be shown as written, but for implementation reasons it's difficult.
+// See `impl Clean for TyKind::Rptr`.
+// @has async_fn/fn.user_elided.html
+// @has - '//pre[@class="rust fn"]' 'pub async fn user_elided(foo: &str) -> &str'
+pub async fn user_elided(foo: &'_ str) -> &str {}
+// @has async_fn/fn.static_trait.html
+// @has - '//pre[@class="rust fn"]' 'pub async fn static_trait(foo: &str) -> Box<dyn Bar>'
+pub async fn static_trait(foo: &str) -> Box<dyn Bar> {}
+// @has async_fn/fn.lifetime_for_trait.html
+// @has - '//pre[@class="rust fn"]' "pub async fn lifetime_for_trait(foo: &str) -> Box<dyn Bar + '_>"
+pub async fn lifetime_for_trait(foo: &str) -> Box<dyn Bar + '_> {}
+// @has async_fn/fn.elided_in_input_trait.html
+// @has - '//pre[@class="rust fn"]' "pub async fn elided_in_input_trait(t: impl Pattern<'_>)"
+pub async fn elided_in_input_trait(t: impl Pattern<'_>) {}
+
+struct AsyncFdReadyGuard<'a, T> { x: &'a T }
+
+impl Foo {
+    // @has async_fn/struct.Foo.html
+    // @has - '//h4[@class="method"]' 'pub async fn complicated_lifetimes( &self, context: &impl Bar) -> impl Iterator<Item = &usize>'
+    pub async fn complicated_lifetimes(&self, context: &impl Bar) -> impl Iterator<Item = &usize> {}
+    // taken from `tokio` as an example of a method that was particularly bad before
+    // @has - '//h4[@class="method"]' "pub async fn readable<T>(&self) -> Result<AsyncFdReadyGuard<'_, T>, ()>"
+    pub async fn readable<T>(&self) -> Result<AsyncFdReadyGuard<'_, T>, ()> {}
+    // @has - '//h4[@class="method"]' "pub async fn mut_self(&mut self)"
+    pub async fn mut_self(&mut self) {}
+}
+
+// test named lifetimes, just in case
+// @has async_fn/fn.named.html
+// @has - '//pre[@class="rust fn"]' "pub async fn named<'a, 'b>(foo: &'a str) -> &'b str"
+pub async fn named<'a, 'b>(foo: &'a str) -> &'b str {}
+// @has async_fn/fn.named_trait.html
+// @has - '//pre[@class="rust fn"]' "pub async fn named_trait<'a, 'b>(foo: impl Pattern<'a>) -> impl Pattern<'b>"
+pub async fn named_trait<'a, 'b>(foo: impl Pattern<'a>) -> impl Pattern<'b> {}

src/test/ui/parser/incorrect-move-async-order-issue-79694.fixed

@@ -0,0 +1,8 @@
+// run-rustfix
+// edition:2018
+
+// Regression test for issue 79694
+
+fn main() {
+    let _ = async move { }; //~ ERROR 7:13: 7:23: the order of `move` and `async` is incorrect
+}

src/test/ui/parser/incorrect-move-async-order-issue-79694.rs

@@ -0,0 +1,8 @@
+// run-rustfix
+// edition:2018
+
+// Regression test for issue 79694
+
+fn main() {
+    let _ = move async { }; //~ ERROR 7:13: 7:23: the order of `move` and `async` is incorrect
+}

src/test/ui/parser/incorrect-move-async-order-issue-79694.stderr

@@ -0,0 +1,13 @@
+error: the order of `move` and `async` is incorrect
+  --> $DIR/incorrect-move-async-order-issue-79694.rs:7:13
+   |
+LL |     let _ = move async { };
+   |             ^^^^^^^^^^
+   |
+help: try switching the order
+   |
+LL |     let _ = async move { };
+   |             ^^^^^^^^^^
+
+error: aborting due to previous error
+

src/tools/x/README.md

@@ -1,3 +1,10 @@
 # x
 
 `x` invokes `x.py` from any subdirectory.
+
+To install, run the following commands:
+
+```
+$ cd rust/src/tools/x/
+$ cargo install --path .
+```