Rollup of 7 pull requests

compiler/rustc_const_eval/src/interpret/visitor.rs

@@ -21,7 +21,7 @@ pub trait ValueVisitor<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>>: Sized {
     /// `read_discriminant` can be hooked for better error messages.
     #[inline(always)]
     fn read_discriminant(&mut self, v: &Self::V) -> InterpResult<'tcx, VariantIdx> {
-        Ok(self.ecx().read_discriminant(&v.to_op(self.ecx())?)?)
+        self.ecx().read_discriminant(&v.to_op(self.ecx())?)
     }
 
     /// This function provides the chance to reorder the order in which fields are visited for

compiler/rustc_driver_impl/src/lib.rs

@@ -587,10 +587,8 @@ fn show_md_content_with_pager(content: &str, color: ColorConfig) {
     let mut print_formatted = if pager_name == "less" {
         cmd.arg("-r");
         true
-    } else if ["bat", "catbat", "delta"].iter().any(|v| *v == pager_name) {
-        true
     } else {
-        false
+        ["bat", "catbat", "delta"].iter().any(|v| *v == pager_name)
     };
 
     if color == ColorConfig::Never {

compiler/rustc_hir_analysis/src/collect/item_bounds.rs

@@ -34,17 +34,14 @@ fn associated_type_bounds<'tcx>(
     let trait_def_id = tcx.local_parent(assoc_item_def_id);
     let trait_predicates = tcx.trait_explicit_predicates_and_bounds(trait_def_id);
 
-    let bounds_from_parent = trait_predicates
-        .predicates
-        .iter()
-        .copied()
-        .filter(|(pred, _)| match pred.kind().skip_binder() {
+    let bounds_from_parent = trait_predicates.predicates.iter().copied().filter(|(pred, _)| {
+        match pred.kind().skip_binder() {
             ty::ClauseKind::Trait(tr) => tr.self_ty() == item_ty,
             ty::ClauseKind::Projection(proj) => proj.projection_ty.self_ty() == item_ty,
             ty::ClauseKind::TypeOutlives(outlives) => outlives.0 == item_ty,
             _ => false,
-        })
-        .map(|(clause, span)| (clause, span));
+        }
+    });
 
     let all_bounds = tcx.arena.alloc_from_iter(bounds.clauses().chain(bounds_from_parent));
     debug!(

compiler/rustc_hir_typeck/src/upvar.rs

@@ -315,11 +315,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let final_tupled_upvars_type = Ty::new_tup(self.tcx, &final_upvar_tys);
         self.demand_suptype(span, args.tupled_upvars_ty(), final_tupled_upvars_type);
 
-        let fake_reads = delegate
-            .fake_reads
-            .into_iter()
-            .map(|(place, cause, hir_id)| (place, cause, hir_id))
-            .collect();
+        let fake_reads = delegate.fake_reads;
+
         self.typeck_results.borrow_mut().closure_fake_reads.insert(closure_def_id, fake_reads);
 
         if self.tcx.sess.opts.unstable_opts.profile_closures {

compiler/rustc_mir_transform/src/jump_threading.rs

@@ -649,7 +649,7 @@ impl OpportunitySet {
 
             // `succ` must be a successor of `current`. If it is not, this means this TO is not
             // satisfiable and a previous TO erased this edge, so we bail out.
-            if basic_blocks[current].terminator().successors().find(|s| *s == succ).is_none() {
+            if !basic_blocks[current].terminator().successors().any(|s| s == succ) {
                 debug!("impossible");
                 return;
             }

compiler/rustc_passes/src/diagnostic_items.rs

@@ -83,6 +83,9 @@ fn all_diagnostic_items(tcx: TyCtxt<'_>, (): ()) -> DiagnosticItems {
 
     // Collect diagnostic items in other crates.
     for &cnum in tcx.crates(()).iter().chain(std::iter::once(&LOCAL_CRATE)) {
+        // We are collecting many DiagnosticItems hash maps into one
+        // DiagnosticItems hash map. The iteration order does not matter.
+        #[allow(rustc::potential_query_instability)]
         for (&name, &def_id) in &tcx.diagnostic_items(cnum).name_to_id {
             collect_item(tcx, &mut items, name, def_id);
         }

compiler/rustc_passes/src/hir_stats.rs

@@ -121,6 +121,8 @@ impl<'k> StatCollector<'k> {
     }
 
     fn print(&self, title: &str, prefix: &str) {
+        // We will soon sort, so the initial order does not matter.
+        #[allow(rustc::potential_query_instability)]
         let mut nodes: Vec<_> = self.nodes.iter().collect();
         nodes.sort_by_key(|(_, node)| node.stats.count * node.stats.size);
 
@@ -147,6 +149,8 @@ impl<'k> StatCollector<'k> {
                 to_readable_str(node.stats.size)
             );
             if !node.subnodes.is_empty() {
+                // We will soon sort, so the initial order does not matter.
+                #[allow(rustc::potential_query_instability)]
                 let mut subnodes: Vec<_> = node.subnodes.iter().collect();
                 subnodes.sort_by_key(|(_, subnode)| subnode.count * subnode.size);
 

compiler/rustc_passes/src/lib.rs

@@ -4,7 +4,6 @@
 //!
 //! This API is completely unstable and subject to change.
 
-#![allow(rustc::potential_query_instability)]
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![doc(rust_logo)]
 #![feature(rustdoc_internals)]

compiler/rustc_passes/src/stability.rs

@@ -1048,6 +1048,9 @@ pub fn check_unused_or_stable_features(tcx: TyCtxt<'_>) {
         tcx.sess.emit_err(errors::UnknownFeature { span, feature: *feature });
     }
 
+    // We only use the hash map contents to emit errors, and the order of
+    // emitted errors do not affect query stability.
+    #[allow(rustc::potential_query_instability)]
     for (implied_by, feature) in remaining_implications {
         let local_defined_features = tcx.lib_features(LOCAL_CRATE);
         let span = local_defined_features

compiler/rustc_pattern_analysis/src/constructor.rs

@@ -979,7 +979,8 @@ impl ConstructorSet {
             && !(pcx.is_top_level && matches!(self, Self::NoConstructors))
         {
             // Treat all missing constructors as nonempty.
-            missing.extend(missing_empty.drain(..));
+            // This clears `missing_empty`.
+            missing.append(&mut missing_empty);
         }
 
         SplitConstructorSet { present, missing, missing_empty }

compiler/rustc_query_system/src/dep_graph/serialized.rs

@@ -70,7 +70,7 @@ const DEP_NODE_PAD: usize = DEP_NODE_SIZE - 1;
 const DEP_NODE_WIDTH_BITS: usize = DEP_NODE_SIZE / 2;
 
 /// Data for use when recompiling the **current crate**.
-#[derive(Debug)]
+#[derive(Debug, Default)]
 pub struct SerializedDepGraph {
     /// The set of all DepNodes in the graph
     nodes: IndexVec<SerializedDepNodeIndex, DepNode>,
@@ -89,18 +89,6 @@ pub struct SerializedDepGraph {
     index: Vec<UnhashMap<PackedFingerprint, SerializedDepNodeIndex>>,
 }
 
-impl Default for SerializedDepGraph {
-    fn default() -> Self {
-        SerializedDepGraph {
-            nodes: Default::default(),
-            fingerprints: Default::default(),
-            edge_list_indices: Default::default(),
-            edge_list_data: Default::default(),
-            index: Default::default(),
-        }
-    }
-}
-
 impl SerializedDepGraph {
     #[inline]
     pub fn edge_targets_from(

compiler/rustc_resolve/src/late/diagnostics.rs

@@ -2178,7 +2178,7 @@ impl<'a: 'ast, 'ast, 'tcx> LateResolutionVisitor<'a, '_, 'ast, 'tcx> {
                 let (span, text) = match path.segments.first() {
                     Some(seg) if let Some(name) = seg.ident.as_str().strip_prefix("let") => {
                         // a special case for #117894
-                        let name = name.strip_prefix("_").unwrap_or(name);
+                        let name = name.strip_prefix('_').unwrap_or(name);
                         (ident_span, format!("let {name}"))
                     }
                     _ => (ident_span.shrink_to_lo(), "let ".to_string()),

compiler/rustc_smir/src/rustc_smir/context.rs

@@ -157,7 +157,7 @@ impl<'tcx> Context for TablesWrapper<'tcx> {
                 (name == crate_name).then(|| smir_crate(tables.tcx, *crate_num))
             })
             .into_iter()
-            .filter_map(|c| c)
+            .flatten()
             .collect();
         crates
     }

compiler/rustc_symbol_mangling/src/typeid/typeid_itanium_cxx_abi.rs

@@ -364,7 +364,7 @@ fn encode_ty_name(tcx: TyCtxt<'_>, def_id: DefId) -> String {
     //     _ZTSFvu27NvNtC1234_5crate6Trait13fooIu22NtC1234_5crate7Struct1Iu3i32ES_EE
     //
     // The reason for not using v0's extended form of paths is to use a consistent and simpler
-    // encoding, as the reasoning for using it isn't relevand for type metadata identifiers (i.e.,
+    // encoding, as the reasoning for using it isn't relevant for type metadata identifiers (i.e.,
     // keep symbol names close to how methods are represented in error messages). See
     // https://rust-lang.github.io/rfcs/2603-rust-symbol-name-mangling-v0.html#methods.
     let mut s = String::new();

compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs

@@ -1069,7 +1069,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
             if !self.tcx.is_diagnostic_item(sym::Result, def.did()) {
                 return None;
             }
-            Some(arg.as_type()?)
+            arg.as_type()
         };
 
         let mut suggested = false;

compiler/rustc_ty_utils/src/layout.rs

@@ -831,7 +831,10 @@ fn coroutine_layout<'tcx>(
                     Assigned(_) => bug!("assignment does not match variant"),
                     Ineligible(_) => false,
                 })
-                .map(|local| subst_field(info.field_tys[*local].ty));
+                .map(|local| {
+                    let field_ty = subst_field(info.field_tys[*local].ty);
+                    Ty::new_maybe_uninit(tcx, field_ty)
+                });
 
             let mut variant = univariant_uninterned(
                 cx,

src/librustdoc/html/markdown.rs

@@ -27,7 +27,7 @@
 //! ```
 
 use rustc_data_structures::fx::FxHashMap;
-use rustc_errors::{DiagnosticMessage, SubdiagnosticMessage};
+use rustc_errors::{DiagnosticBuilder, DiagnosticMessage};
 use rustc_hir::def_id::DefId;
 use rustc_middle::ty::TyCtxt;
 pub(crate) use rustc_resolve::rustdoc::main_body_opts;
@@ -234,10 +234,6 @@ impl<'a, I: Iterator<Item = Event<'a>>> Iterator for CodeBlocks<'_, 'a, I> {
 
     fn next(&mut self) -> Option<Self::Item> {
         let event = self.inner.next();
-        let compile_fail;
-        let should_panic;
-        let ignore;
-        let edition;
         let Some(Event::Start(Tag::CodeBlock(kind))) = event else {
             return event;
         };
@@ -253,49 +249,44 @@ impl<'a, I: Iterator<Item = Event<'a>>> Iterator for CodeBlocks<'_, 'a, I> {
             }
         }
 
-        let parse_result = match kind {
-            CodeBlockKind::Fenced(ref lang) => {
-                let parse_result = LangString::parse_without_check(
-                    lang,
-                    self.check_error_codes,
-                    false,
-                    self.custom_code_classes_in_docs,
-                );
-                if !parse_result.rust {
-                    let added_classes = parse_result.added_classes;
-                    let lang_string = if let Some(lang) = parse_result.unknown.first() {
-                        format!("language-{}", lang)
-                    } else {
-                        String::new()
-                    };
-                    let whitespace = if added_classes.is_empty() { "" } else { " " };
-                    return Some(Event::Html(
-                        format!(
-                            "<div class=\"example-wrap\">\
+        let LangString { added_classes, compile_fail, should_panic, ignore, edition, .. } =
+            match kind {
+                CodeBlockKind::Fenced(ref lang) => {
+                    let parse_result = LangString::parse_without_check(
+                        lang,
+                        self.check_error_codes,
+                        false,
+                        self.custom_code_classes_in_docs,
+                    );
+                    if !parse_result.rust {
+                        let added_classes = parse_result.added_classes;
+                        let lang_string = if let Some(lang) = parse_result.unknown.first() {
+                            format!("language-{}", lang)
+                        } else {
+                            String::new()
+                        };
+                        let whitespace = if added_classes.is_empty() { "" } else { " " };
+                        return Some(Event::Html(
+                            format!(
+                                "<div class=\"example-wrap\">\
                                  <pre class=\"{lang_string}{whitespace}{added_classes}\">\
                                      <code>{text}</code>\
                                  </pre>\
                              </div>",
-                            added_classes = added_classes.join(" "),
-                            text = Escape(&original_text),
-                        )
-                        .into(),
-                    ));
+                                added_classes = added_classes.join(" "),
+                                text = Escape(&original_text),
+                            )
+                            .into(),
+                        ));
+                    }
+                    parse_result
                 }
-                parse_result
-            }
-            CodeBlockKind::Indented => Default::default(),
-        };
+                CodeBlockKind::Indented => Default::default(),
+            };
 
-        let added_classes = parse_result.added_classes;
         let lines = original_text.lines().filter_map(|l| map_line(l).for_html());
         let text = lines.intersperse("\n".into()).collect::<String>();
 
-        compile_fail = parse_result.compile_fail;
-        should_panic = parse_result.should_panic;
-        ignore = parse_result.ignore;
-        edition = parse_result.edition;
-
         let explicit_edition = edition.is_some();
         let edition = edition.unwrap_or(self.edition);
 
@@ -852,15 +843,17 @@ impl<'tcx> ExtraInfo<'tcx> {
     fn error_invalid_codeblock_attr_with_help(
         &self,
         msg: impl Into<DiagnosticMessage>,
-        help: impl Into<SubdiagnosticMessage>,
+        f: impl for<'a, 'b> FnOnce(
+            &'b mut DiagnosticBuilder<'a, ()>,
+        ) -> &'b mut DiagnosticBuilder<'a, ()>,
     ) {
         if let Some(def_id) = self.def_id.as_local() {
             self.tcx.struct_span_lint_hir(
                 crate::lint::INVALID_CODEBLOCK_ATTRIBUTES,
                 self.tcx.local_def_id_to_hir_id(def_id),
                 self.sp,
                 msg,
-                |lint| lint.help(help),
+                f,
             );
         }
     }
@@ -1293,6 +1286,21 @@ impl LangString {
                     LangStringToken::LangToken(x) if x.starts_with("edition") => {
                         data.edition = x[7..].parse::<Edition>().ok();
                     }
+                    LangStringToken::LangToken(x)
+                        if x.starts_with("rust") && x[4..].parse::<Edition>().is_ok() =>
+                    {
+                        if let Some(extra) = extra {
+                            extra.error_invalid_codeblock_attr_with_help(
+                                format!("unknown attribute `{x}`"),
+                                |lint| {
+                                    lint.help(format!(
+                                        "there is an attribute with a similar name: `edition{}`",
+                                        &x[4..],
+                                    ))
+                                },
+                            );
+                        }
+                    }
                     LangStringToken::LangToken(x)
                         if allow_error_code_check && x.starts_with('E') && x.len() == 5 =>
                     {
@@ -1337,8 +1345,13 @@ impl LangString {
                         } {
                             if let Some(extra) = extra {
                                 extra.error_invalid_codeblock_attr_with_help(
-                                    format!("unknown attribute `{x}`. Did you mean `{flag}`?"),
-                                    help,
+                                    format!("unknown attribute `{x}`"),
+                                    |lint| {
+                                        lint.help(format!(
+                                            "there is an attribute with a similar name: `{flag}`"
+                                        ))
+                                        .help(help)
+                                    },
                                 );
                             }
                         }

src/librustdoc/html/render/type_layout.rs

@@ -79,6 +79,7 @@ pub(crate) fn document_type_layout<'a, 'cx: 'a>(
             TypeLayoutSize { is_unsized, is_uninhabited, size }
         });
 
-        Ok(TypeLayout { variants, type_layout_size }.render_into(f).unwrap())
+        TypeLayout { variants, type_layout_size }.render_into(f).unwrap();
+        Ok(())
     })
 }