Auto merge of #92064 - matthiaskrgr:rollup-tgj2pai, r=matthiaskrgr

Rollup of 7 pull requests

Successful merges:

 - #91858 (pass -Wl,-z,origin to set DF_ORIGIN when using rpath)
 - #91923 (Remove `in_band_lifetimes` from `rustc_query_impl`)
 - #91925 (Remove `in_band_lifetimes` from `rustc_privacy`)
 - #91977 (Clean up search code and unify function returned values)
 - #92018 (Fix typo in "new region bound" suggestion)
 - #92022 (Eliminate duplicate codes of expected_found_bool)
 - #92032 (hir: Do not introduce dummy type names for `extern` blocks in def paths)

Failed merges:

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

compiler/rustc_codegen_ssa/src/back/rpath.rs

@@ -23,9 +23,12 @@ pub fn get_rpath_flags(config: &mut RPathConfig<'_>) -> Vec<String> {
     let rpaths = get_rpaths(config);
     let mut flags = rpaths_to_flags(&rpaths);
 
-    // Use DT_RUNPATH instead of DT_RPATH if available
     if config.linker_is_gnu {
+        // Use DT_RUNPATH instead of DT_RPATH if available
         flags.push("-Wl,--enable-new-dtags".to_owned());
+
+        // Set DF_ORIGIN for substitute $ORIGIN
+        flags.push("-Wl,-z,origin".to_owned());
     }
 
     flags

compiler/rustc_hir/src/definitions.rs

@@ -267,6 +267,8 @@ pub enum DefPathData {
     // Different kinds of items and item-like things:
     /// An impl.
     Impl,
+    /// An `extern` block.
+    ForeignMod,
     /// Something in the type namespace.
     TypeNs(Symbol),
     /// Something in the value namespace.
@@ -469,7 +471,9 @@ impl DefPathData {
         match *self {
             TypeNs(name) | ValueNs(name) | MacroNs(name) | LifetimeNs(name) => Some(name),
 
-            Impl | CrateRoot | Misc | ClosureExpr | Ctor | AnonConst | ImplTrait => None,
+            Impl | ForeignMod | CrateRoot | Misc | ClosureExpr | Ctor | AnonConst | ImplTrait => {
+                None
+            }
         }
     }
 
@@ -482,6 +486,7 @@ impl DefPathData {
             // Note that this does not show up in user print-outs.
             CrateRoot => DefPathDataName::Anon { namespace: kw::Crate },
             Impl => DefPathDataName::Anon { namespace: kw::Impl },
+            ForeignMod => DefPathDataName::Anon { namespace: kw::Extern },
             Misc => DefPathDataName::Anon { namespace: sym::misc },
             ClosureExpr => DefPathDataName::Anon { namespace: sym::closure },
             Ctor => DefPathDataName::Anon { namespace: sym::constructor },

compiler/rustc_infer/src/infer/combine.rs

@@ -37,7 +37,7 @@ use crate::traits::{Obligation, PredicateObligations};
 use rustc_data_structures::sso::SsoHashMap;
 use rustc_hir::def_id::DefId;
 use rustc_middle::traits::ObligationCause;
-use rustc_middle::ty::error::TypeError;
+use rustc_middle::ty::error::{ExpectedFound, TypeError};
 use rustc_middle::ty::relate::{self, Relate, RelateResult, TypeRelation};
 use rustc_middle::ty::subst::SubstsRef;
 use rustc_middle::ty::{self, InferConst, ToPredicate, Ty, TyCtxt, TypeFoldable};
@@ -790,7 +790,7 @@ pub fn const_unification_error<'tcx>(
     a_is_expected: bool,
     (a, b): (&'tcx ty::Const<'tcx>, &'tcx ty::Const<'tcx>),
 ) -> TypeError<'tcx> {
-    TypeError::ConstMismatch(ty::relate::expected_found_bool(a_is_expected, a, b))
+    TypeError::ConstMismatch(ExpectedFound::new(a_is_expected, a, b))
 }
 
 fn int_unification_error<'tcx>(
@@ -798,7 +798,7 @@ fn int_unification_error<'tcx>(
     v: (ty::IntVarValue, ty::IntVarValue),
 ) -> TypeError<'tcx> {
     let (a, b) = v;
-    TypeError::IntMismatch(ty::relate::expected_found_bool(a_is_expected, a, b))
+    TypeError::IntMismatch(ExpectedFound::new(a_is_expected, a, b))
 }
 
 fn float_unification_error<'tcx>(
@@ -806,7 +806,7 @@ fn float_unification_error<'tcx>(
     v: (ty::FloatVarValue, ty::FloatVarValue),
 ) -> TypeError<'tcx> {
     let (ty::FloatVarValue(a), ty::FloatVarValue(b)) = v;
-    TypeError::FloatMismatch(ty::relate::expected_found_bool(a_is_expected, a, b))
+    TypeError::FloatMismatch(ExpectedFound::new(a_is_expected, a, b))
 }
 
 struct ConstInferUnifier<'cx, 'tcx> {

compiler/rustc_infer/src/infer/error_reporting/mod.rs

@@ -275,7 +275,7 @@ pub fn unexpected_hidden_region_diagnostic(
                     fn_returns,
                     hidden_region.to_string(),
                     None,
-                    format!("captures {}", hidden_region),
+                    format!("captures `{}`", hidden_region),
                     None,
                 )
             }

compiler/rustc_lint/src/context.rs

@@ -1030,8 +1030,8 @@ impl<'tcx> LateContext<'tcx> {
             ) -> Result<Self::Path, Self::Error> {
                 let mut path = print_prefix(self)?;
 
-                // Skip `::{{constructor}}` on tuple/unit structs.
+                // Skip `::{{extern}}` blocks and `::{{constructor}}` on tuple/unit structs.
-                if let DefPathData::Ctor = disambiguated_data.data {
+                if let DefPathData::ForeignMod | DefPathData::Ctor = disambiguated_data.data {
                     return Ok(path);
                 }
 

compiler/rustc_middle/src/ty/print/pretty.rs

@@ -1740,31 +1740,27 @@ impl<F: fmt::Write> Printer<'tcx> for FmtPrinter<'_, 'tcx, F> {
     ) -> Result<Self::Path, Self::Error> {
         self = print_prefix(self)?;
 
-        // Skip `::{{constructor}}` on tuple/unit structs.
+        // Skip `::{{extern}}` blocks and `::{{constructor}}` on tuple/unit structs.
-        if let DefPathData::Ctor = disambiguated_data.data {
+        if let DefPathData::ForeignMod | DefPathData::Ctor = disambiguated_data.data {
             return Ok(self);
         }
 
-        // FIXME(eddyb) `name` should never be empty, but it
-        // currently is for `extern { ... }` "foreign modules".
         let name = disambiguated_data.data.name();
-        if name != DefPathDataName::Named(kw::Empty) {
+        if !self.empty_path {
-            if !self.empty_path {
+            write!(self, "::")?;
-                write!(self, "::")?;
-            }
-
-            if let DefPathDataName::Named(name) = name {
-                if Ident::with_dummy_span(name).is_raw_guess() {
-                    write!(self, "r#")?;
-                }
-            }
-
-            let verbose = self.tcx.sess.verbose();
-            disambiguated_data.fmt_maybe_verbose(&mut self, verbose)?;
-
-            self.empty_path = false;
         }
 
+        if let DefPathDataName::Named(name) = name {
+            if Ident::with_dummy_span(name).is_raw_guess() {
+                write!(self, "r#")?;
+            }
+        }
+
+        let verbose = self.tcx.sess.verbose();
+        disambiguated_data.fmt_maybe_verbose(&mut self, verbose)?;
+
+        self.empty_path = false;
+
         Ok(self)
     }
 

compiler/rustc_middle/src/ty/relate.rs

@@ -836,13 +836,5 @@ pub fn expected_found<R, T>(relation: &mut R, a: T, b: T) -> ExpectedFound<T>
 where
     R: TypeRelation<'tcx>,
 {
-    expected_found_bool(relation.a_is_expected(), a, b)
+    ExpectedFound::new(relation.a_is_expected(), a, b)
-}
-
-pub fn expected_found_bool<T>(a_is_expected: bool, a: T, b: T) -> ExpectedFound<T> {
-    if a_is_expected {
-        ExpectedFound { expected: a, found: b }
-    } else {
-        ExpectedFound { expected: b, found: a }
-    }
 }

compiler/rustc_privacy/src/lib.rs

@@ -1,5 +1,4 @@
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
-#![feature(in_band_lifetimes)]
 #![feature(nll)]
 #![feature(control_flow_enum)]
 #![feature(try_blocks)]
@@ -310,7 +309,7 @@ struct PubRestrictedVisitor<'tcx> {
     has_pub_restricted: bool,
 }
 
-impl Visitor<'tcx> for PubRestrictedVisitor<'tcx> {
+impl<'tcx> Visitor<'tcx> for PubRestrictedVisitor<'tcx> {
     type Map = Map<'tcx>;
 
     fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
@@ -432,7 +431,7 @@ struct ReachEverythingInTheInterfaceVisitor<'a, 'tcx> {
     ev: &'a mut EmbargoVisitor<'tcx>,
 }
 
-impl EmbargoVisitor<'tcx> {
+impl<'tcx> EmbargoVisitor<'tcx> {
     fn get(&self, def_id: LocalDefId) -> Option<AccessLevel> {
         self.access_levels.map.get(&def_id).copied()
     }
@@ -674,7 +673,7 @@ impl EmbargoVisitor<'tcx> {
     }
 }
 
-impl Visitor<'tcx> for EmbargoVisitor<'tcx> {
+impl<'tcx> Visitor<'tcx> for EmbargoVisitor<'tcx> {
     type Map = Map<'tcx>;
 
     /// We want to visit items in the context of their containing
@@ -944,7 +943,7 @@ impl Visitor<'tcx> for EmbargoVisitor<'tcx> {
     }
 }
 
-impl ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
+impl ReachEverythingInTheInterfaceVisitor<'_, '_> {
     fn generics(&mut self) -> &mut Self {
         for param in &self.ev.tcx.generics_of(self.item_def_id).params {
             match param.kind {
@@ -983,7 +982,7 @@ impl ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
     }
 }
 
-impl DefIdVisitor<'tcx> for ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
+impl<'tcx> DefIdVisitor<'tcx> for ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
     fn tcx(&self) -> TyCtxt<'tcx> {
         self.ev.tcx
     }
@@ -1413,7 +1412,7 @@ impl<'tcx> Visitor<'tcx> for TypePrivacyVisitor<'tcx> {
     }
 }
 
-impl DefIdVisitor<'tcx> for TypePrivacyVisitor<'tcx> {
+impl<'tcx> DefIdVisitor<'tcx> for TypePrivacyVisitor<'tcx> {
     fn tcx(&self) -> TyCtxt<'tcx> {
         self.tcx
     }
@@ -1800,7 +1799,7 @@ struct SearchInterfaceForPrivateItemsVisitor<'tcx> {
     in_assoc_ty: bool,
 }
 
-impl SearchInterfaceForPrivateItemsVisitor<'tcx> {
+impl SearchInterfaceForPrivateItemsVisitor<'_> {
     fn generics(&mut self) -> &mut Self {
         for param in &self.tcx.generics_of(self.item_def_id).params {
             match param.kind {
@@ -1921,7 +1920,7 @@ impl SearchInterfaceForPrivateItemsVisitor<'tcx> {
     }
 }
 
-impl DefIdVisitor<'tcx> for SearchInterfaceForPrivateItemsVisitor<'tcx> {
+impl<'tcx> DefIdVisitor<'tcx> for SearchInterfaceForPrivateItemsVisitor<'tcx> {
     fn tcx(&self) -> TyCtxt<'tcx> {
         self.tcx
     }

compiler/rustc_query_impl/src/keys.rs

@@ -151,7 +151,7 @@ impl Key for (DefId, DefId) {
     }
 }
 
-impl Key for (ty::Instance<'tcx>, LocalDefId) {
+impl<'tcx> Key for (ty::Instance<'tcx>, LocalDefId) {
     #[inline(always)]
     fn query_crate_is_local(&self) -> bool {
         true

compiler/rustc_query_impl/src/lib.rs

@@ -2,7 +2,6 @@
 
 #![doc(html_root_url = "https://doc.rust-lang.org/nightly/nightly-rustc/")]
 #![feature(crate_visibility_modifier)]
-#![feature(in_band_lifetimes)]
 #![feature(nll)]
 #![feature(min_specialization)]
 #![feature(once_cell)]

compiler/rustc_query_impl/src/on_disk_cache.rs

@@ -212,7 +212,7 @@ impl<'sess> rustc_middle::ty::OnDiskCache<'sess> for OnDiskCache<'sess> {
     /// Cache promotions require invoking queries, which needs to read the serialized data.
     /// In order to serialize the new on-disk cache, the former on-disk cache file needs to be
     /// deleted, hence we won't be able to refer to its memmapped data.
-    fn drop_serialized_data(&self, tcx: TyCtxt<'tcx>) {
+    fn drop_serialized_data(&self, tcx: TyCtxt<'_>) {
         // Load everything into memory so we can write it out to the on-disk
         // cache. The vast majority of cacheable query results should already
         // be in memory, so this should be a cheap operation.

compiler/rustc_query_impl/src/plumbing.rs

@@ -31,7 +31,7 @@ impl<'tcx> std::ops::Deref for QueryCtxt<'tcx> {
     }
 }
 
-impl HasDepContext for QueryCtxt<'tcx> {
+impl<'tcx> HasDepContext for QueryCtxt<'tcx> {
     type DepKind = rustc_middle::dep_graph::DepKind;
     type DepContext = TyCtxt<'tcx>;
 
@@ -41,7 +41,7 @@ impl HasDepContext for QueryCtxt<'tcx> {
     }
 }
 
-impl QueryContext for QueryCtxt<'tcx> {
+impl QueryContext for QueryCtxt<'_> {
     fn current_query_job(&self) -> Option<QueryJobId<Self::DepKind>> {
         tls::with_related_context(**self, |icx| icx.query)
     }
@@ -130,7 +130,7 @@ impl<'tcx> QueryCtxt<'tcx> {
 
     pub(super) fn encode_query_results(
         self,
-        encoder: &mut on_disk_cache::CacheEncoder<'a, 'tcx, opaque::FileEncoder>,
+        encoder: &mut on_disk_cache::CacheEncoder<'_, 'tcx, opaque::FileEncoder>,
         query_result_index: &mut on_disk_cache::EncodedDepNodeIndex,
     ) -> opaque::FileEncodeResult {
         macro_rules! encode_queries {
@@ -511,7 +511,7 @@ macro_rules! define_queries_struct {
             }
         }
 
-        impl QueryEngine<'tcx> for Queries<'tcx> {
+        impl<'tcx> QueryEngine<'tcx> for Queries<'tcx> {
             fn as_any(&'tcx self) -> &'tcx dyn std::any::Any {
                 let this = unsafe { std::mem::transmute::<&Queries<'_>, &Queries<'_>>(self) };
                 this as _

compiler/rustc_query_impl/src/profiling_support.rs

@@ -295,7 +295,7 @@ fn alloc_self_profile_query_strings_for_query_cache<'tcx, C>(
 /// If we are recording only summary data, the ids will point to
 /// just the query names. If we are recording query keys too, we
 /// allocate the corresponding strings here.
-pub fn alloc_self_profile_query_strings(tcx: TyCtxt<'tcx>) {
+pub fn alloc_self_profile_query_strings(tcx: TyCtxt<'_>) {
     if !tcx.prof.enabled() {
         return;
     }

compiler/rustc_resolve/src/def_collector.rs

@@ -92,6 +92,7 @@ impl<'a, 'b> visit::Visitor<'a> for DefCollector<'a, 'b> {
         // information we encapsulate into, the better
         let def_data = match &i.kind {
             ItemKind::Impl { .. } => DefPathData::Impl,
+            ItemKind::ForeignMod(..) => DefPathData::ForeignMod,
             ItemKind::Mod(..)
             | ItemKind::Trait(..)
             | ItemKind::TraitAlias(..)
@@ -99,7 +100,6 @@ impl<'a, 'b> visit::Visitor<'a> for DefCollector<'a, 'b> {
             | ItemKind::Struct(..)
             | ItemKind::Union(..)
             | ItemKind::ExternCrate(..)
-            | ItemKind::ForeignMod(..)
             | ItemKind::TyAlias(..) => DefPathData::TypeNs(i.ident.name),
             ItemKind::Static(..) | ItemKind::Const(..) | ItemKind::Fn(..) => {
                 DefPathData::ValueNs(i.ident.name)

compiler/rustc_symbol_mangling/src/legacy.rs

@@ -311,8 +311,8 @@ impl<'tcx> Printer<'tcx> for &mut SymbolPrinter<'tcx> {
     ) -> Result<Self::Path, Self::Error> {
         self = print_prefix(self)?;
 
-        // Skip `::{{constructor}}` on tuple/unit structs.
+        // Skip `::{{extern}}` blocks and `::{{constructor}}` on tuple/unit structs.
-        if let DefPathData::Ctor = disambiguated_data.data {
+        if let DefPathData::ForeignMod | DefPathData::Ctor = disambiguated_data.data {
             return Ok(self);
         }
 

compiler/rustc_symbol_mangling/src/v0.rs

@@ -771,6 +771,10 @@ impl<'tcx> Printer<'tcx> for &mut SymbolMangler<'tcx> {
         disambiguated_data: &DisambiguatedDefPathData,
     ) -> Result<Self::Path, Self::Error> {
         let ns = match disambiguated_data.data {
+            // FIXME: It shouldn't be necessary to add anything for extern block segments,
+            // but we add 't' for backward compatibility.
+            DefPathData::ForeignMod => 't',
+
             // Uppercase categories are more stable than lowercase ones.
             DefPathData::TypeNs(_) => 't',
             DefPathData::ValueNs(_) => 'v',

compiler/rustc_typeck/src/check/expr.rs

@@ -36,8 +36,8 @@ use rustc_infer::infer;
 use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
 use rustc_infer::infer::InferOk;
 use rustc_middle::ty::adjustment::{Adjust, Adjustment, AllowTwoPhase};
+use rustc_middle::ty::error::ExpectedFound;
 use rustc_middle::ty::error::TypeError::{FieldMisMatch, Sorts};
-use rustc_middle::ty::relate::expected_found_bool;
 use rustc_middle::ty::subst::SubstsRef;
 use rustc_middle::ty::{self, AdtKind, Ty, TypeFoldable};
 use rustc_session::parse::feature_err;
@@ -1493,7 +1493,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                         &self.misc(base_expr.span),
                                         adt_ty,
                                         base_ty,
-                                        Sorts(expected_found_bool(true, adt_ty, base_ty)),
+                                        Sorts(ExpectedFound::new(true, adt_ty, base_ty)),
                                     )
                                     .emit();
                             }

src/bootstrap/builder.rs

@@ -1176,6 +1176,7 @@ impl<'a> Builder<'a> {
                 rustflags.arg("-Zosx-rpath-install-name");
                 Some("-Wl,-rpath,@loader_path/../lib")
             } else if !target.contains("windows") {
+                rustflags.arg("-Clink-args=-Wl,-z,origin");
                 Some("-Wl,-rpath,$ORIGIN/../lib")
             } else {
                 None

src/librustdoc/clean/inline.rs

@@ -8,6 +8,7 @@ use rustc_data_structures::fx::FxHashSet;
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, Res};
 use rustc_hir::def_id::DefId;
+use rustc_hir::definitions::DefPathData;
 use rustc_hir::Mutability;
 use rustc_metadata::creader::{CStore, LoadedMacro};
 use rustc_middle::ty::{self, TyCtxt};
@@ -165,9 +166,8 @@ crate fn record_extern_fqn(cx: &mut DocContext<'_>, did: DefId, kind: ItemType)
     let crate_name = cx.tcx.crate_name(did.krate).to_string();
 
     let relative = cx.tcx.def_path(did).data.into_iter().filter_map(|elem| {
-        // extern blocks have an empty name
+        // Filter out extern blocks
-        let s = elem.data.to_string();
+        (elem.data != DefPathData::ForeignMod).then(|| elem.data.to_string())
-        if !s.is_empty() { Some(s) } else { None }
     });
     let fqn = if let ItemType::Macro = kind {
         // Check to see if it is a macro 2.0 or built-in macro

src/librustdoc/html/static/js/search.js

@@ -176,16 +176,13 @@ window.initSearch = function(rawSearchIndex) {
             var ar = [];
             for (var entry in results) {
                 if (hasOwnPropertyRustdoc(results, entry)) {
-                    ar.push(results[entry]);
+                    var result = results[entry];
+                    result.word = searchWords[result.id];
+                    result.item = searchIndex[result.id] || {};
+                    ar.push(result);
                 }
             }
             results = ar;
-            var i, len, result;
-            for (i = 0, len = results.length; i < len; ++i) {
-                result = results[i];
-                result.word = searchWords[result.id];
-                result.item = searchIndex[result.id] || {};
-            }
             // if there are no results then return to default and fail
             if (results.length === 0) {
                 return [];
@@ -258,7 +255,7 @@ window.initSearch = function(rawSearchIndex) {
                 return 0;
             });
 
-            for (i = 0, len = results.length; i < len; ++i) {
+            for (var i = 0, len = results.length; i < len; ++i) {
                 result = results[i];
 
                 // this validation does not make sense when searching by types
@@ -344,7 +341,17 @@ window.initSearch = function(rawSearchIndex) {
             return MAX_LEV_DISTANCE + 1;
         }
 
-        // Check for type name and type generics (if any).
+        /**
+          * This function checks if the object (`obj`) matches the given type (`val`) and its
+          * generics (if any).
+          *
+          * @param {Object} obj
+          * @param {string} val
+          * @param {boolean} literalSearch
+          *
+          * @return {integer} - Returns a Levenshtein distance to the best match. If there is
+          *                     no match, returns `MAX_LEV_DISTANCE + 1`.
+          */
         function checkType(obj, val, literalSearch) {
             var lev_distance = MAX_LEV_DISTANCE + 1;
             var tmp_lev = MAX_LEV_DISTANCE + 1;
@@ -363,24 +370,23 @@ window.initSearch = function(rawSearchIndex) {
                                 elems[obj[GENERICS_DATA][x][NAME]] += 1;
                             }
 
-                            var allFound = true;
                             len = val.generics.length;
                             for (x = 0; x < len; ++x) {
                                 firstGeneric = val.generics[x];
                                 if (elems[firstGeneric]) {
                                     elems[firstGeneric] -= 1;
                                 } else {
-                                    allFound = false;
+                                    // Something wasn't found and this is a literal search so
-                                    break;
+                                    // abort and return a "failing" distance.
+                                    return MAX_LEV_DISTANCE + 1;
                                 }
                             }
-                            if (allFound) {
+                            // Everything was found, success!
-                                return true;
+                            return 0;
-                            }
                         }
-                        return false;
+                        return MAX_LEV_DISTANCE + 1;
                     }
-                    return true;
+                    return 0;
                 } else {
                     // If the type has generics but don't match, then it won't return at this point.
                     // Otherwise, `checkGenerics` will return 0 and it'll return.
@@ -392,14 +398,15 @@ window.initSearch = function(rawSearchIndex) {
                     }
                 }
             } else if (literalSearch) {
+                var found = false;
                 if ((!val.generics || val.generics.length === 0) &&
                       obj.length > GENERICS_DATA && obj[GENERICS_DATA].length > 0) {
-                    return obj[GENERICS_DATA].some(
+                    found = obj[GENERICS_DATA].some(
                         function(gen) {
                             return gen[NAME] === val.name;
                         });
                 }
-                return false;
+                return found ? 0 : MAX_LEV_DISTANCE + 1;
             }
             lev_distance = Math.min(levenshtein(obj[NAME], val.name), lev_distance);
             if (lev_distance <= MAX_LEV_DISTANCE) {
@@ -430,6 +437,17 @@ window.initSearch = function(rawSearchIndex) {
             return Math.min(lev_distance, tmp_lev) + 1;
         }
 
+        /**
+         * This function checks if the object (`obj`) has an argument with the given type (`val`).
+         *
+         * @param {Object} obj
+         * @param {string} val
+         * @param {boolean} literalSearch
+         * @param {integer} typeFilter
+         *
+         * @return {integer} - Returns a Levenshtein distance to the best match. If there is no
+         *                      match, returns `MAX_LEV_DISTANCE + 1`.
+         */
         function findArg(obj, val, literalSearch, typeFilter) {
             var lev_distance = MAX_LEV_DISTANCE + 1;
 
@@ -441,19 +459,15 @@ window.initSearch = function(rawSearchIndex) {
                         continue;
                     }
                     tmp = checkType(tmp, val, literalSearch);
-                    if (literalSearch) {
+                    if (tmp === 0) {
-                        if (tmp) {
+                        return 0;
-                            return true;
+                    } else if (literalSearch) {
-                        }
                         continue;
                     }
                     lev_distance = Math.min(tmp, lev_distance);
-                    if (lev_distance === 0) {
-                        return 0;
-                    }
                 }
             }
-            return literalSearch ? false : lev_distance;
+            return literalSearch ? MAX_LEV_DISTANCE + 1 : lev_distance;
         }
 
         function checkReturned(obj, val, literalSearch, typeFilter) {
@@ -470,19 +484,15 @@ window.initSearch = function(rawSearchIndex) {
                         continue;
                     }
                     tmp = checkType(tmp, val, literalSearch);
-                    if (literalSearch) {
+                    if (tmp === 0) {
-                        if (tmp) {
+                        return 0;
-                            return true;
+                    } else if (literalSearch) {
-                        }
                         continue;
                     }
                     lev_distance = Math.min(tmp, lev_distance);
-                    if (lev_distance === 0) {
-                        return 0;
-                    }
                 }
             }
-            return literalSearch ? false : lev_distance;
+            return literalSearch ? MAX_LEV_DISTANCE + 1 : lev_distance;
         }
 
         function checkPath(contains, lastElem, ty) {
@@ -612,6 +622,44 @@ window.initSearch = function(rawSearchIndex) {
             onEach(crateAliases, pushFunc);
         }
 
+        /**
+         * This function adds the given result into the provided `res` map if it matches the
+         * following condition:
+         *
+         * * If it is a "literal search" (`isExact`), then `lev` must be 0.
+         * * If it is not a "literal search", `lev` must be <= `MAX_LEV_DISTANCE`.
+         *
+         * The `res` map contains information which will be used to sort the search results:
+         *
+         * * `fullId` is a `string`` used as the key of the object we use for the `res` map.
+         * * `id` is the index in both `searchWords` and `searchIndex` arrays for this element.
+         * * `index` is an `integer`` used to sort by the position of the word in the item's name.
+         * * `lev` is the main metric used to sort the search results.
+         *
+         * @param {boolean} isExact
+         * @param {Object} res
+         * @param {string} fullId
+         * @param {integer} id
+         * @param {integer} index
+         * @param {integer} lev
+         */
+        function addIntoResults(isExact, res, fullId, id, index, lev) {
+            if (lev === 0 || (!isExact && lev <= MAX_LEV_DISTANCE)) {
+                if (res[fullId] !== undefined) {
+                    var result = res[fullId];
+                    if (result.dontValidate || result.lev <= lev) {
+                        return;
+                    }
+                }
+                res[fullId] = {
+                    id: id,
+                    index: index,
+                    dontValidate: isExact,
+                    lev: lev,
+                };
+            }
+        }
+
         // quoted values mean literal search
         var nSearchWords = searchWords.length;
         var i, it;
@@ -634,28 +682,11 @@ window.initSearch = function(rawSearchIndex) {
                 fullId = ty.id;
 
                 if (searchWords[i] === val.name
-                    && typePassesFilter(typeFilter, searchIndex[i].ty)
+                    && typePassesFilter(typeFilter, searchIndex[i].ty)) {
-                    && results[fullId] === undefined) {
+                    addIntoResults(true, results, fullId, i, -1, 0);
-                    results[fullId] = {
-                        id: i,
-                        index: -1,
-                        dontValidate: true,
-                    };
-                }
-                if (in_args && results_in_args[fullId] === undefined) {
-                    results_in_args[fullId] = {
-                        id: i,
-                        index: -1,
-                        dontValidate: true,
-                    };
-                }
-                if (returned && results_returned[fullId] === undefined) {
-                    results_returned[fullId] = {
-                        id: i,
-                        index: -1,
-                        dontValidate: true,
-                    };
                 }
+                addIntoResults(true, results_in_args, fullId, i, -1, in_args);
+                addIntoResults(true, results_returned, fullId, i, -1, returned);
             }
             query.inputs = [val];
             query.output = val;
@@ -684,39 +715,27 @@ window.initSearch = function(rawSearchIndex) {
                 fullId = ty.id;
 
                 returned = checkReturned(ty, output, true, NO_TYPE_FILTER);
-                if (output.name === "*" || returned) {
+                if (output.name === "*" || returned === 0) {
                     in_args = false;
                     var is_module = false;
 
                     if (input === "*") {
                         is_module = true;
                     } else {
-                        var allFound = true;
+                        var firstNonZeroDistance = 0;
-                        for (it = 0, len = inputs.length; allFound && it < len; it++) {
+                        for (it = 0, len = inputs.length; it < len; it++) {
-                            allFound = checkType(type, inputs[it], true);
+                            var distance = checkType(type, inputs[it], true);
+                            if (distance > 0) {
+                                firstNonZeroDistance = distance;
+                                break;
+                            }
                         }
-                        in_args = allFound;
+                        in_args = firstNonZeroDistance;
-                    }
-                    if (in_args) {
-                        results_in_args[fullId] = {
-                            id: i,
-                            index: -1,
-                            dontValidate: true,
-                        };
-                    }
-                    if (returned) {
-                        results_returned[fullId] = {
-                            id: i,
-                            index: -1,
-                            dontValidate: true,
-                        };
                     }
+                    addIntoResults(true, results_in_args, fullId, i, -1, in_args);
+                    addIntoResults(true, results_returned, fullId, i, -1, returned);
                     if (is_module) {
-                        results[fullId] = {
+                        addIntoResults(true, results, fullId, i, -1, 0);
-                            id: i,
-                            index: -1,
-                            dontValidate: true,
-                        };
                     }
                 }
             }
@@ -788,41 +807,14 @@ window.initSearch = function(rawSearchIndex) {
                         lev = 0;
                     }
                 }
-                if (in_args <= MAX_LEV_DISTANCE) {
+                addIntoResults(false, results_in_args, fullId, j, index, in_args);
-                    if (results_in_args[fullId] === undefined) {
+                addIntoResults(false, results_returned, fullId, j, index, returned);
-                        results_in_args[fullId] = {
-                            id: j,
-                            index: index,
-                            lev: in_args,
-                        };
-                    }
-                    results_in_args[fullId].lev =
-                        Math.min(results_in_args[fullId].lev, in_args);
-                }
-                if (returned <= MAX_LEV_DISTANCE) {
-                    if (results_returned[fullId] === undefined) {
-                        results_returned[fullId] = {
-                            id: j,
-                            index: index,
-                            lev: returned,
-                        };
-                    }
-                    results_returned[fullId].lev =
-                        Math.min(results_returned[fullId].lev, returned);
-                }
                 if (typePassesFilter(typeFilter, ty.ty) &&
                         (index !== -1 || lev <= MAX_LEV_DISTANCE)) {
                     if (index !== -1 && paths.length < 2) {
                         lev = 0;
                     }
-                    if (results[fullId] === undefined) {
+                    addIntoResults(false, results, fullId, j, index, lev);
-                        results[fullId] = {
-                            id: j,
-                            index: index,
-                            lev: lev,
-                        };
-                    }
-                    results[fullId].lev = Math.min(results[fullId].lev, lev);
                 }
             }
         }

src/librustdoc/visit_ast.rs

@@ -5,6 +5,7 @@ use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir as hir;
 use rustc_hir::def::{DefKind, Res};
 use rustc_hir::def_id::DefId;
+use rustc_hir::definitions::DefPathData;
 use rustc_hir::Node;
 use rustc_hir::CRATE_HIR_ID;
 use rustc_middle::middle::privacy::AccessLevel;
@@ -45,9 +46,8 @@ impl Module<'hir> {
 fn def_id_to_path(tcx: TyCtxt<'_>, did: DefId) -> Vec<String> {
     let crate_name = tcx.crate_name(did.krate).to_string();
     let relative = tcx.def_path(did).data.into_iter().filter_map(|elem| {
-        // extern blocks have an empty name
+        // Filter out extern blocks
-        let s = elem.data.to_string();
+        (elem.data != DefPathData::ForeignMod).then(|| elem.data.to_string())
-        if !s.is_empty() { Some(s) } else { None }
     });
     std::iter::once(crate_name).chain(relative).collect()
 }

src/test/ui/async-await/multiple-lifetimes/ret-impl-trait-one.nll.stderr

@@ -21,7 +21,7 @@ LL | async fn async_ret_impl_trait1<'a, 'b>(a: &'a u8, b: &'b u8) -> impl Trait<
    |                                    |
    |                                    hidden type `(&'a u8, &'b u8)` captures the lifetime `'b` as defined here
    |
-help: to declare that the `impl Trait` captures 'b, you can add an explicit `'b` lifetime bound
+help: to declare that the `impl Trait` captures `'b`, you can add an explicit `'b` lifetime bound
    |
 LL | async fn async_ret_impl_trait1<'a, 'b>(a: &'a u8, b: &'b u8) -> impl Trait<'a> + 'b {
    |                                                                                ++++

src/test/ui/async-await/multiple-lifetimes/ret-impl-trait-one.stderr

@@ -16,7 +16,7 @@ LL | async fn async_ret_impl_trait1<'a, 'b>(a: &'a u8, b: &'b u8) -> impl Trait<
    |                                    |
    |                                    hidden type `(&'a u8, &'b u8)` captures the lifetime `'b` as defined here
    |
-help: to declare that the `impl Trait` captures 'b, you can add an explicit `'b` lifetime bound
+help: to declare that the `impl Trait` captures `'b`, you can add an explicit `'b` lifetime bound
    |
 LL | async fn async_ret_impl_trait1<'a, 'b>(a: &'a u8, b: &'b u8) -> impl Trait<'a> + 'b {
    |                                                                                ++++

src/test/ui/impl-trait/hidden-lifetimes.stderr

@@ -6,7 +6,7 @@ LL | fn hide_ref<'a, 'b, T: 'static>(x: &'a mut &'b T) -> impl Swap + 'a {
    |                 |
    |                 hidden type `&'a mut &'b T` captures the lifetime `'b` as defined here
    |
-help: to declare that the `impl Trait` captures 'b, you can add an explicit `'b` lifetime bound
+help: to declare that the `impl Trait` captures `'b`, you can add an explicit `'b` lifetime bound
    |
 LL | fn hide_ref<'a, 'b, T: 'static>(x: &'a mut &'b T) -> impl Swap + 'a + 'b {
    |                                                                     ++++
@@ -19,7 +19,7 @@ LL | fn hide_rc_refcell<'a, 'b: 'a, T: 'static>(x: Rc<RefCell<&'b T>>) -> impl S
    |                        |
    |                        hidden type `Rc<RefCell<&'b T>>` captures the lifetime `'b` as defined here
    |
-help: to declare that the `impl Trait` captures 'b, you can add an explicit `'b` lifetime bound
+help: to declare that the `impl Trait` captures `'b`, you can add an explicit `'b` lifetime bound
    |
 LL | fn hide_rc_refcell<'a, 'b: 'a, T: 'static>(x: Rc<RefCell<&'b T>>) -> impl Swap + 'a + 'b {
    |                                                                                     ++++

src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unrelated.stderr

@@ -6,7 +6,7 @@ LL | fn upper_bounds<'a, 'b, 'c, 'd, 'e>(a: Ordinary<'a>, b: Ordinary<'b>) -> im
    |                     |
    |                     hidden type `Ordinary<'b>` captures the lifetime `'b` as defined here
    |
-help: to declare that the `impl Trait` captures 'b, you can add an explicit `'b` lifetime bound
+help: to declare that the `impl Trait` captures `'b`, you can add an explicit `'b` lifetime bound
    |
 LL | fn upper_bounds<'a, 'b, 'c, 'd, 'e>(a: Ordinary<'a>, b: Ordinary<'b>) -> impl Trait<'d, 'e> + 'b
    |                                                                                             ++++

src/test/ui/impl-trait/multiple-lifetimes/ordinary-bounds-unsuited.stderr

@@ -6,7 +6,7 @@ LL | fn upper_bounds<'a, 'b>(a: Ordinary<'a>, b: Ordinary<'b>) -> impl Trait<'a,
    |                     |
    |                     hidden type `Ordinary<'b>` captures the lifetime `'b` as defined here
    |
-help: to declare that the `impl Trait` captures 'b, you can add an explicit `'b` lifetime bound
+help: to declare that the `impl Trait` captures `'b`, you can add an explicit `'b` lifetime bound
    |
 LL | fn upper_bounds<'a, 'b>(a: Ordinary<'a>, b: Ordinary<'b>) -> impl Trait<'a, 'b> + 'b
    |                                                                                 ++++

src/test/ui/impl-trait/must_outlive_least_region_or_bound.nll.stderr

@@ -6,7 +6,7 @@ LL | fn elided(x: &i32) -> impl Copy { x }
    |              |
    |              hidden type `&i32` captures the anonymous lifetime defined here
    |
-help: to declare that the `impl Trait` captures '_, you can add an explicit `'_` lifetime bound
+help: to declare that the `impl Trait` captures `'_`, you can add an explicit `'_` lifetime bound
    |
 LL | fn elided(x: &i32) -> impl Copy + '_ { x }
    |                                 ++++
@@ -19,7 +19,7 @@ LL | fn explicit<'a>(x: &'a i32) -> impl Copy { x }
    |             |
    |             hidden type `&'a i32` captures the lifetime `'a` as defined here
    |
-help: to declare that the `impl Trait` captures 'a, you can add an explicit `'a` lifetime bound
+help: to declare that the `impl Trait` captures `'a`, you can add an explicit `'a` lifetime bound
    |
 LL | fn explicit<'a>(x: &'a i32) -> impl Copy + 'a { x }
    |                                          ++++
@@ -74,7 +74,7 @@ LL | fn move_lifetime_into_fn<'a, 'b>(x: &'a u32, y: &'b u32) -> impl Fn(&'a u32
    |                              |
    |                              hidden type `[closure@$DIR/must_outlive_least_region_or_bound.rs:35:5: 35:31]` captures the lifetime `'b` as defined here
    |
-help: to declare that the `impl Trait` captures 'b, you can add an explicit `'b` lifetime bound
+help: to declare that the `impl Trait` captures `'b`, you can add an explicit `'b` lifetime bound
    |
 LL | fn move_lifetime_into_fn<'a, 'b>(x: &'a u32, y: &'b u32) -> impl Fn(&'a u32) + 'b {
    |                                                                              ++++

src/test/ui/impl-trait/must_outlive_least_region_or_bound.stderr

@@ -6,7 +6,7 @@ LL | fn elided(x: &i32) -> impl Copy { x }
    |              |
    |              hidden type `&i32` captures the anonymous lifetime defined here
    |
-help: to declare that the `impl Trait` captures '_, you can add an explicit `'_` lifetime bound
+help: to declare that the `impl Trait` captures `'_`, you can add an explicit `'_` lifetime bound
    |
 LL | fn elided(x: &i32) -> impl Copy + '_ { x }
    |                                 ++++
@@ -19,7 +19,7 @@ LL | fn explicit<'a>(x: &'a i32) -> impl Copy { x }
    |             |
    |             hidden type `&'a i32` captures the lifetime `'a` as defined here
    |
-help: to declare that the `impl Trait` captures 'a, you can add an explicit `'a` lifetime bound
+help: to declare that the `impl Trait` captures `'a`, you can add an explicit `'a` lifetime bound
    |
 LL | fn explicit<'a>(x: &'a i32) -> impl Copy + 'a { x }
    |                                          ++++
@@ -119,7 +119,7 @@ LL | fn move_lifetime_into_fn<'a, 'b>(x: &'a u32, y: &'b u32) -> impl Fn(&'a u32
    |                              |
    |                              hidden type `[closure@$DIR/must_outlive_least_region_or_bound.rs:35:5: 35:31]` captures the lifetime `'b` as defined here
    |
-help: to declare that the `impl Trait` captures 'b, you can add an explicit `'b` lifetime bound
+help: to declare that the `impl Trait` captures `'b`, you can add an explicit `'b` lifetime bound
    |
 LL | fn move_lifetime_into_fn<'a, 'b>(x: &'a u32, y: &'b u32) -> impl Fn(&'a u32) + 'b {
    |                                                                              ++++

src/test/ui/impl-trait/region-escape-via-bound.stderr

@@ -7,7 +7,7 @@ LL |
 LL | where 'x: 'y
    |       -- hidden type `Cell<&'x u32>` captures the lifetime `'x` as defined here
    |
-help: to declare that the `impl Trait` captures 'x, you can add an explicit `'x` lifetime bound
+help: to declare that the `impl Trait` captures `'x`, you can add an explicit `'x` lifetime bound
    |
 LL | fn foo(x: Cell<&'x u32>) -> impl Trait<'y> + 'x
    |                                            ++++

src/test/ui/impl-trait/static-return-lifetime-infered.stderr

@@ -6,7 +6,7 @@ LL |     fn iter_values_anon(&self) -> impl Iterator<Item=u32> {
    |                         |
    |                         hidden type `Map<std::slice::Iter<'_, (u32, u32)>, [closure@$DIR/static-return-lifetime-infered.rs:9:27: 9:34]>` captures the anonymous lifetime defined here
    |
-help: to declare that the `impl Trait` captures '_, you can add an explicit `'_` lifetime bound
+help: to declare that the `impl Trait` captures `'_`, you can add an explicit `'_` lifetime bound
    |
 LL |     fn iter_values_anon(&self) -> impl Iterator<Item=u32> + '_ {
    |                                                           ++++
@@ -19,7 +19,7 @@ LL |     fn iter_values_anon(&self) -> impl Iterator<Item=u32> {
    |                         |
    |                         hidden type `Map<std::slice::Iter<'_, (u32, u32)>, [closure@$DIR/static-return-lifetime-infered.rs:9:27: 9:34]>` captures the anonymous lifetime defined here
    |
-help: to declare that the `impl Trait` captures '_, you can add an explicit `'_` lifetime bound
+help: to declare that the `impl Trait` captures `'_`, you can add an explicit `'_` lifetime bound
    |
 LL |     fn iter_values_anon(&self) -> impl Iterator<Item=u32> + '_ {
    |                                                           ++++
@@ -32,7 +32,7 @@ LL |     fn iter_values<'a>(&'a self) -> impl Iterator<Item=u32> {
    |                    |
    |                    hidden type `Map<std::slice::Iter<'a, (u32, u32)>, [closure@$DIR/static-return-lifetime-infered.rs:14:27: 14:34]>` captures the lifetime `'a` as defined here
    |
-help: to declare that the `impl Trait` captures 'a, you can add an explicit `'a` lifetime bound
+help: to declare that the `impl Trait` captures `'a`, you can add an explicit `'a` lifetime bound
    |
 LL |     fn iter_values<'a>(&'a self) -> impl Iterator<Item=u32> + 'a {
    |                                                             ++++
@@ -45,7 +45,7 @@ LL |     fn iter_values<'a>(&'a self) -> impl Iterator<Item=u32> {
    |                    |
    |                    hidden type `Map<std::slice::Iter<'a, (u32, u32)>, [closure@$DIR/static-return-lifetime-infered.rs:14:27: 14:34]>` captures the lifetime `'a` as defined here
    |
-help: to declare that the `impl Trait` captures 'a, you can add an explicit `'a` lifetime bound
+help: to declare that the `impl Trait` captures `'a`, you can add an explicit `'a` lifetime bound
    |
 LL |     fn iter_values<'a>(&'a self) -> impl Iterator<Item=u32> + 'a {
    |                                                             ++++

src/test/ui/nll/ty-outlives/impl-trait-captures.stderr

@@ -6,7 +6,7 @@ LL | fn foo<'a, T>(x: &T) -> impl Foo<'a> {
    |                  |
    |                  hidden type `&ReFree(DefId(0:8 ~ impl_trait_captures[HASH]::foo), BrAnon(0)) T` captures the anonymous lifetime defined here
    |
-help: to declare that the `impl Trait` captures ReFree(DefId(0:8 ~ impl_trait_captures[HASH]::foo), BrAnon(0)), you can add an explicit `ReFree(DefId(0:8 ~ impl_trait_captures[HASH]::foo), BrAnon(0))` lifetime bound
+help: to declare that the `impl Trait` captures `ReFree(DefId(0:8 ~ impl_trait_captures[HASH]::foo), BrAnon(0))`, you can add an explicit `ReFree(DefId(0:8 ~ impl_trait_captures[HASH]::foo), BrAnon(0))` lifetime bound
    |
 LL | fn foo<'a, T>(x: &T) -> impl Foo<'a> + ReFree(DefId(0:8 ~ impl_trait_captures[HASH]::foo), BrAnon(0)) {
    |                                      ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait-async.stderr

@@ -6,7 +6,7 @@ LL |     async fn f(self: Pin<&Self>) -> impl Clone { self }
    |                          |
    |                          hidden type `Pin<&Foo>` captures the lifetime `'_` as defined here
    |
-help: to declare that the `impl Trait` captures '_, you can add an explicit `'_` lifetime bound
+help: to declare that the `impl Trait` captures `'_`, you can add an explicit `'_` lifetime bound
    |
 LL |     async fn f(self: Pin<&Self>) -> impl Clone + '_ { self }
    |                                                ++++

src/test/ui/self/arbitrary_self_types_pin_lifetime_impl_trait.stderr

@@ -6,7 +6,7 @@ LL |     fn f(self: Pin<&Self>) -> impl Clone { self }
    |                    |
    |                    hidden type `Pin<&Foo>` captures the anonymous lifetime defined here
    |
-help: to declare that the `impl Trait` captures '_, you can add an explicit `'_` lifetime bound
+help: to declare that the `impl Trait` captures `'_`, you can add an explicit `'_` lifetime bound
    |
 LL |     fn f(self: Pin<&Self>) -> impl Clone + '_ { self }
    |                                          ++++