Auto merge of #116605 - GuillaumeGomez:rollup-12ba2o6, r=GuillaumeGomez

Rollup of 7 pull requests

Successful merges:

 - #109422 (rustdoc-search: add impl disambiguator to duplicate assoc items)
 - #116250 (On type error of closure call argument, point at earlier calls that affected inference)
 - #116444 (add test for const-eval error in dead code during monomorphization)
 - #116503 (Update docs for mips target tier demotion.)
 - #116559 (Mark `new_in` as `const` for BTree collections)
 - #116560 (In smir use `FxIndexMap` to store indexed ids)
 - #116574 (Update books)

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

38 files changed, 697 insertions, 106 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 082bb4be93c..2882ec0682e 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -4504,6 +4504,7 @@ dependencies = [
 name = "rustc_smir"
 version = "0.0.0"
 dependencies = [
+ "rustc_data_structures",
  "rustc_driver",
  "rustc_hir",
  "rustc_interface",
diff --git a/RELEASES.md b/RELEASES.md
index e261294a032..1cc110e6607 100644
--- a/RELEASES.md
+++ b/RELEASES.md
@@ -229,6 +229,7 @@ Compatibility Notes
   this should only impact users of other registries, or people who don't publish
   to a registry.
   [#12291](https://github.com/rust-lang/cargo/pull/12291)
+- [Demoted `mips*-unknown-linux-gnu*` targets from host tier 2 to target tier 3 support.](https://github.com/rust-lang/rust/pull/113274)
 
 Version 1.71.1 (2023-08-03)
 ===========================
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs
index c0332a48be3..9b7f8f80310 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs
@@ -16,6 +16,7 @@ use rustc_errors::{
 use rustc_hir as hir;
 use rustc_hir::def::{CtorOf, DefKind, Res};
 use rustc_hir::def_id::DefId;
+use rustc_hir::intravisit::Visitor;
 use rustc_hir::{ExprKind, Node, QPath};
 use rustc_hir_analysis::astconv::AstConv;
 use rustc_hir_analysis::check::intrinsicck::InlineAsmCtxt;
@@ -28,7 +29,7 @@ use rustc_infer::infer::TypeTrace;
 use rustc_infer::infer::{DefineOpaqueTypes, InferOk};
 use rustc_middle::ty::adjustment::AllowTwoPhase;
 use rustc_middle::ty::visit::TypeVisitableExt;
-use rustc_middle::ty::{self, IsSuggestable, Ty};
+use rustc_middle::ty::{self, IsSuggestable, Ty, TyCtxt};
 use rustc_session::Session;
 use rustc_span::symbol::{kw, Ident};
 use rustc_span::{self, sym, BytePos, Span};
@@ -722,6 +723,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         &mut err,
                         fn_def_id,
                         callee_ty,
+                        call_expr,
+                        None,
                         Some(mismatch_idx),
                         is_method,
                     );
@@ -826,6 +829,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 &mut err,
                 fn_def_id,
                 callee_ty,
+                call_expr,
+                Some(expected_ty),
                 Some(expected_idx.as_usize()),
                 is_method,
             );
@@ -1208,7 +1213,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         }
 
         // Call out where the function is defined
-        self.label_fn_like(&mut err, fn_def_id, callee_ty, None, is_method);
+        self.label_fn_like(&mut err, fn_def_id, callee_ty, call_expr, None, None, is_method);
 
         // And add a suggestion block for all of the parameters
         let suggestion_text = match suggestion_text {
@@ -1899,6 +1904,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         err: &mut Diagnostic,
         callable_def_id: Option<DefId>,
         callee_ty: Option<Ty<'tcx>>,
+        call_expr: &'tcx hir::Expr<'tcx>,
+        expected_ty: Option<Ty<'tcx>>,
         // A specific argument should be labeled, instead of all of them
         expected_idx: Option<usize>,
         is_method: bool,
@@ -2015,6 +2022,46 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             let param = expected_idx
                 .and_then(|expected_idx| self.tcx.hir().body(*body).params.get(expected_idx));
             let (kind, span) = if let Some(param) = param {
+                // Try to find earlier invocations of this closure to find if the type mismatch
+                // is because of inference. If we find one, point at them.
+                let mut call_finder = FindClosureArg { tcx: self.tcx, calls: vec![] };
+                let node = self.tcx
+                    .opt_local_def_id_to_hir_id(self.tcx.hir().get_parent_item(call_expr.hir_id))
+                    .and_then(|hir_id| self.tcx.hir().find(hir_id));
+                match node {
+                    Some(hir::Node::Item(item)) => call_finder.visit_item(item),
+                    Some(hir::Node::TraitItem(item)) => call_finder.visit_trait_item(item),
+                    Some(hir::Node::ImplItem(item)) => call_finder.visit_impl_item(item),
+                    _ => {}
+                }
+                let typeck = self.typeck_results.borrow();
+                for (rcvr, args) in call_finder.calls {
+                    if let Some(rcvr_ty) = typeck.node_type_opt(rcvr.hir_id)
+                        && let ty::Closure(call_def_id, _) = rcvr_ty.kind()
+                        && def_id == *call_def_id
+                        && let Some(idx) = expected_idx
+                        && let Some(arg) = args.get(idx)
+                        && let Some(arg_ty) = typeck.node_type_opt(arg.hir_id)
+                        && let Some(expected_ty) = expected_ty
+                        && self.can_eq(self.param_env, arg_ty, expected_ty)
+                    {
+                        let mut sp: MultiSpan = vec![arg.span].into();
+                        sp.push_span_label(
+                            arg.span,
+                            format!("expected because this argument is of type `{arg_ty}`"),
+                        );
+                        sp.push_span_label(rcvr.span, "in this closure call");
+                        err.span_note(
+                            sp,
+                            format!(
+                                "expected because the closure was earlier called with an \
+                                argument of type `{arg_ty}`",
+                            ),
+                        );
+                        break;
+                    }
+                }
+
                 ("closure parameter", param.span)
             } else {
                 ("closure", self.tcx.def_span(def_id))
@@ -2028,3 +2075,23 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         }
     }
 }
+
+struct FindClosureArg<'tcx> {
+    tcx: TyCtxt<'tcx>,
+    calls: Vec<(&'tcx hir::Expr<'tcx>, &'tcx [hir::Expr<'tcx>])>,
+}
+
+impl<'tcx> Visitor<'tcx> for FindClosureArg<'tcx> {
+    type NestedFilter = rustc_middle::hir::nested_filter::All;
+
+    fn nested_visit_map(&mut self) -> Self::Map {
+        self.tcx.hir()
+    }
+
+    fn visit_expr(&mut self, ex: &'tcx hir::Expr<'tcx>) {
+        if let hir::ExprKind::Call(rcvr, args) = ex.kind {
+            self.calls.push((rcvr, args));
+        }
+        hir::intravisit::walk_expr(self, ex);
+    }
+}
diff --git a/compiler/rustc_smir/Cargo.toml b/compiler/rustc_smir/Cargo.toml
index 3e0d6baab6a..2b77044d6bf 100644
--- a/compiler/rustc_smir/Cargo.toml
+++ b/compiler/rustc_smir/Cargo.toml
@@ -4,6 +4,7 @@ version = "0.0.0"
 edition = "2021"
 
 [dependencies]
+rustc_data_structures = { path = "../rustc_data_structures" }
 rustc_driver = { path = "../rustc_driver" }
 rustc_hir = { path = "../rustc_hir" }
 rustc_interface = { path = "../rustc_interface" }
diff --git a/compiler/rustc_smir/src/rustc_internal/mod.rs b/compiler/rustc_smir/src/rustc_internal/mod.rs
index 36eb2247253..e3c84f06543 100644
--- a/compiler/rustc_smir/src/rustc_internal/mod.rs
+++ b/compiler/rustc_smir/src/rustc_internal/mod.rs
@@ -3,24 +3,27 @@
 //! For that, we define APIs that will temporarily be public to 3P that exposes rustc internal APIs
 //! until stable MIR is complete.
 
-use std::ops::{ControlFlow, Index};
-
 use crate::rustc_internal;
 use crate::rustc_smir::Tables;
+use rustc_data_structures::fx;
 use rustc_driver::{Callbacks, Compilation, RunCompiler};
 use rustc_interface::{interface, Queries};
 use rustc_middle::mir::interpret::AllocId;
 use rustc_middle::ty::TyCtxt;
 use rustc_span::def_id::{CrateNum, DefId};
 use rustc_span::Span;
+use stable_mir::ty::IndexedVal;
 use stable_mir::CompilerError;
+use std::fmt::Debug;
+use std::hash::Hash;
+use std::ops::{ControlFlow, Index};
 
 impl<'tcx> Index<stable_mir::DefId> for Tables<'tcx> {
     type Output = DefId;
 
     #[inline(always)]
     fn index(&self, index: stable_mir::DefId) -> &Self::Output {
-        &self.def_ids[index.0]
+        &self.def_ids[index]
     }
 }
 
@@ -29,7 +32,7 @@ impl<'tcx> Index<stable_mir::ty::Span> for Tables<'tcx> {
 
     #[inline(always)]
     fn index(&self, index: stable_mir::ty::Span) -> &Self::Output {
-        &self.spans[index.0]
+        &self.spans[index]
     }
 }
 
@@ -95,36 +98,15 @@ impl<'tcx> Tables<'tcx> {
     }
 
     fn create_def_id(&mut self, did: DefId) -> stable_mir::DefId {
-        // FIXME: this becomes inefficient when we have too many ids
-        for (i, &d) in self.def_ids.iter().enumerate() {
-            if d == did {
-                return stable_mir::DefId(i);
-            }
-        }
-        let id = self.def_ids.len();
-        self.def_ids.push(did);
-        stable_mir::DefId(id)
+        self.def_ids.create_or_fetch(did)
     }
 
     fn create_alloc_id(&mut self, aid: AllocId) -> stable_mir::AllocId {
-        // FIXME: this becomes inefficient when we have too many ids
-        if let Some(i) = self.alloc_ids.iter().position(|a| *a == aid) {
-            return stable_mir::AllocId(i);
-        };
-        let id = self.def_ids.len();
-        self.alloc_ids.push(aid);
-        stable_mir::AllocId(id)
+        self.alloc_ids.create_or_fetch(aid)
     }
 
     pub(crate) fn create_span(&mut self, span: Span) -> stable_mir::ty::Span {
-        for (i, &sp) in self.spans.iter().enumerate() {
-            if sp == span {
-                return stable_mir::ty::Span(i);
-            }
-        }
-        let id = self.spans.len();
-        self.spans.push(span);
-        stable_mir::ty::Span(id)
+        self.spans.create_or_fetch(span)
     }
 }
 
@@ -134,7 +116,13 @@ pub fn crate_num(item: &stable_mir::Crate) -> CrateNum {
 
 pub fn run(tcx: TyCtxt<'_>, f: impl FnOnce()) {
     stable_mir::run(
-        Tables { tcx, def_ids: vec![], alloc_ids: vec![], spans: vec![], types: vec![] },
+        Tables {
+            tcx,
+            def_ids: rustc_internal::IndexMap { index_map: fx::FxIndexMap::default() },
+            alloc_ids: rustc_internal::IndexMap { index_map: fx::FxIndexMap::default() },
+            spans: rustc_internal::IndexMap { index_map: fx::FxIndexMap::default() },
+            types: vec![],
+        },
         f,
     );
 }
@@ -197,3 +185,29 @@ where
         })
     }
 }
+
+/// Simmilar to rustc's `FxIndexMap`, `IndexMap` with extra
+/// safety features added.
+pub struct IndexMap<K, V> {
+    index_map: fx::FxIndexMap<K, V>,
+}
+
+impl<K: PartialEq + Hash + Eq, V: Copy + Debug + PartialEq + IndexedVal> IndexMap<K, V> {
+    pub fn create_or_fetch(&mut self, key: K) -> V {
+        let len = self.index_map.len();
+        let v = self.index_map.entry(key).or_insert(V::to_val(len));
+        *v
+    }
+}
+
+impl<K: PartialEq + Hash + Eq, V: Copy + Debug + PartialEq + IndexedVal> Index<V>
+    for IndexMap<K, V>
+{
+    type Output = K;
+
+    fn index(&self, index: V) -> &Self::Output {
+        let (k, v) = self.index_map.get_index(index.to_index()).unwrap();
+        assert_eq!(*v, index, "Provided value doesn't match with indexed value");
+        k
+    }
+}
diff --git a/compiler/rustc_smir/src/rustc_smir/mod.rs b/compiler/rustc_smir/src/rustc_smir/mod.rs
index 0c474192240..2a265fc1f5b 100644
--- a/compiler/rustc_smir/src/rustc_smir/mod.rs
+++ b/compiler/rustc_smir/src/rustc_smir/mod.rs
@@ -7,6 +7,7 @@
 //!
 //! For now, we are developing everything inside `rustc`, thus, we keep this module private.
 
+use crate::rustc_internal::IndexMap;
 use crate::rustc_smir::hir::def::DefKind;
 use crate::rustc_smir::stable_mir::ty::{BoundRegion, EarlyBoundRegion, Region};
 use rustc_hir as hir;
@@ -201,9 +202,9 @@ impl<S, R: PartialEq> PartialEq<R> for MaybeStable<S, R> {
 
 pub struct Tables<'tcx> {
     pub tcx: TyCtxt<'tcx>,
-    pub def_ids: Vec<DefId>,
-    pub alloc_ids: Vec<AllocId>,
-    pub spans: Vec<rustc_span::Span>,
+    pub def_ids: IndexMap<DefId, stable_mir::DefId>,
+    pub alloc_ids: IndexMap<AllocId, stable_mir::AllocId>,
+    pub spans: IndexMap<rustc_span::Span, Span>,
     pub types: Vec<MaybeStable<stable_mir::ty::TyKind, Ty<'tcx>>>,
 }
 
diff --git a/compiler/stable_mir/src/lib.rs b/compiler/stable_mir/src/lib.rs
index 79f598b6faa..f371f46204f 100644
--- a/compiler/stable_mir/src/lib.rs
+++ b/compiler/stable_mir/src/lib.rs
@@ -22,7 +22,8 @@ use std::fmt;
 use std::fmt::Debug;
 
 use self::ty::{
-    GenericPredicates, Generics, ImplDef, ImplTrait, Span, TraitDecl, TraitDef, Ty, TyKind,
+    GenericPredicates, Generics, ImplDef, ImplTrait, IndexedVal, Span, TraitDecl, TraitDef, Ty,
+    TyKind,
 };
 
 #[macro_use]
@@ -41,7 +42,7 @@ pub type CrateNum = usize;
 
 /// A unique identification number for each item accessible for the current compilation unit.
 #[derive(Clone, Copy, PartialEq, Eq)]
-pub struct DefId(pub usize);
+pub struct DefId(usize);
 
 impl Debug for DefId {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
@@ -52,9 +53,28 @@ impl Debug for DefId {
     }
 }
 
+impl IndexedVal for DefId {
+    fn to_val(index: usize) -> Self {
+        DefId(index)
+    }
+
+    fn to_index(&self) -> usize {
+        self.0
+    }
+}
+
 /// A unique identification number for each provenance
 #[derive(Clone, Copy, PartialEq, Eq, Debug)]
-pub struct AllocId(pub usize);
+pub struct AllocId(usize);
+
+impl IndexedVal for AllocId {
+    fn to_val(index: usize) -> Self {
+        AllocId(index)
+    }
+    fn to_index(&self) -> usize {
+        self.0
+    }
+}
 
 /// A list of crate items.
 pub type CrateItems = Vec<CrateItem>;
diff --git a/compiler/stable_mir/src/ty.rs b/compiler/stable_mir/src/ty.rs
index 6029e3c11ad..691af15da8c 100644
--- a/compiler/stable_mir/src/ty.rs
+++ b/compiler/stable_mir/src/ty.rs
@@ -75,7 +75,7 @@ pub struct Placeholder<T> {
 }
 
 #[derive(Clone, Copy, PartialEq, Eq)]
-pub struct Span(pub usize);
+pub struct Span(usize);
 
 impl Debug for Span {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
@@ -86,6 +86,15 @@ impl Debug for Span {
     }
 }
 
+impl IndexedVal for Span {
+    fn to_val(index: usize) -> Self {
+        Span(index)
+    }
+    fn to_index(&self) -> usize {
+        self.0
+    }
+}
+
 #[derive(Clone, Debug)]
 pub enum TyKind {
     RigidTy(RigidTy),
@@ -565,3 +574,9 @@ pub enum ImplPolarity {
     Negative,
     Reservation,
 }
+
+pub trait IndexedVal {
+    fn to_val(index: usize) -> Self;
+
+    fn to_index(&self) -> usize;
+}
diff --git a/library/alloc/src/collections/btree/map.rs b/library/alloc/src/collections/btree/map.rs
index 5481b327d69..4bdd9639557 100644
--- a/library/alloc/src/collections/btree/map.rs
+++ b/library/alloc/src/collections/btree/map.rs
@@ -669,7 +669,7 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> {
     /// map.insert(1, "a");
     /// ```
     #[unstable(feature = "btreemap_alloc", issue = "32838")]
-    pub fn new_in(alloc: A) -> BTreeMap<K, V, A> {
+    pub const fn new_in(alloc: A) -> BTreeMap<K, V, A> {
         BTreeMap { root: None, length: 0, alloc: ManuallyDrop::new(alloc), _marker: PhantomData }
     }
 }
diff --git a/library/alloc/src/collections/btree/set.rs b/library/alloc/src/collections/btree/set.rs
index 9da230915b8..0e03551286e 100644
--- a/library/alloc/src/collections/btree/set.rs
+++ b/library/alloc/src/collections/btree/set.rs
@@ -358,7 +358,7 @@ impl<T, A: Allocator + Clone> BTreeSet<T, A> {
     /// let mut set: BTreeSet<i32> = BTreeSet::new_in(Global);
     /// ```
     #[unstable(feature = "btreemap_alloc", issue = "32838")]
-    pub fn new_in(alloc: A) -> BTreeSet<T, A> {
+    pub const fn new_in(alloc: A) -> BTreeSet<T, A> {
         BTreeSet { map: BTreeMap::new_in(alloc) }
     }
 
diff --git a/src/doc/reference b/src/doc/reference
-Subproject 5262e1c3b43a2c489df8f6717683a44c7a2260f
+Subproject 142b2ed77d33f37a9973772bd95e6144ed9dce4
diff --git a/src/doc/rust-by-example b/src/doc/rust-by-example
-Subproject c954202c1e1720cba5628f99543cc01188c7d6f
+Subproject 8eb3a01ab74c567b7174784892fb807f2c632d6
diff --git a/src/doc/rustc-dev-guide b/src/doc/rustc-dev-guide
-Subproject a13b7c28ed705891c681ce5417b3d1cdb12cecd
+Subproject b98af7d661e4744baab81fb8dc7a049e44a4a99
diff --git a/src/doc/rustc/src/platform-support.md b/src/doc/rustc/src/platform-support.md
index 1fb5e56db5d..d25fa661c3f 100644
--- a/src/doc/rustc/src/platform-support.md
+++ b/src/doc/rustc/src/platform-support.md
@@ -286,6 +286,10 @@ target | std | host | notes
 `mipsel-unknown-linux-musl` | ✓ |  | MIPS (little endian) Linux with musl libc
 `mipsel-sony-psp` | * |  | MIPS (LE) Sony PlayStation Portable (PSP)
 [`mipsel-sony-psx`](platform-support/mipsel-sony-psx.md) | * |  | MIPS (LE) Sony PlayStation 1 (PSX)
+`mips-unknown-linux-gnu` | MIPS Linux (kernel 4.4, glibc 2.23)
+`mips64-unknown-linux-gnuabi64` | MIPS64 Linux, n64 ABI (kernel 4.4, glibc 2.23)
+`mips64el-unknown-linux-gnuabi64` | MIPS64 (LE) Linux, n64 ABI (kernel 4.4, glibc 2.23)
+`mipsel-unknown-linux-gnu` | MIPS (LE) Linux (kernel 4.4, glibc 2.23)
 `mipsel-unknown-linux-uclibc` | ✓ |  | MIPS (LE) Linux with uClibc
 `mipsel-unknown-none` | * |  | Bare MIPS (LE) softfloat
 [`mipsisa32r6-unknown-linux-gnu`](platform-support/mips-release-6.md) | ? |  | 32-bit MIPS Release 6 Big Endian
diff --git a/src/librustdoc/formats/cache.rs b/src/librustdoc/formats/cache.rs
index 4c6e7dfb987..b916baecc14 100644
--- a/src/librustdoc/formats/cache.rs
+++ b/src/librustdoc/formats/cache.rs
@@ -223,17 +223,16 @@ impl<'a, 'tcx> DocFolder for CacheBuilder<'a, 'tcx> {
 
         // If the impl is from a masked crate or references something from a
         // masked crate then remove it completely.
-        if let clean::ImplItem(ref i) = *item.kind {
-            if self.cache.masked_crates.contains(&item.item_id.krate())
+        if let clean::ImplItem(ref i) = *item.kind &&
+            (self.cache.masked_crates.contains(&item.item_id.krate())
                 || i.trait_
                     .as_ref()
                     .map_or(false, |t| self.cache.masked_crates.contains(&t.def_id().krate))
                 || i.for_
                     .def_id(self.cache)
-                    .map_or(false, |d| self.cache.masked_crates.contains(&d.krate))
-            {
-                return None;
-            }
+                    .map_or(false, |d| self.cache.masked_crates.contains(&d.krate)))
+        {
+            return None;
         }
 
         // Propagate a trait method's documentation to all implementors of the
@@ -334,33 +333,37 @@ impl<'a, 'tcx> DocFolder for CacheBuilder<'a, 'tcx> {
                     // A crate has a module at its root, containing all items,
                     // which should not be indexed. The crate-item itself is
                     // inserted later on when serializing the search-index.
-                    if item.item_id.as_def_id().map_or(false, |idx| !idx.is_crate_root()) {
+                    if item.item_id.as_def_id().map_or(false, |idx| !idx.is_crate_root())
+                        && let ty = item.type_()
+                        && (ty != ItemType::StructField
+                            || u16::from_str_radix(s.as_str(), 10).is_err())
+                    {
                         let desc =
                             short_markdown_summary(&item.doc_value(), &item.link_names(self.cache));
-                        let ty = item.type_();
-                        if ty != ItemType::StructField
-                            || u16::from_str_radix(s.as_str(), 10).is_err()
-                        {
-                            // In case this is a field from a tuple struct, we don't add it into
-                            // the search index because its name is something like "0", which is
-                            // not useful for rustdoc search.
-                            self.cache.search_index.push(IndexItem {
-                                ty,
-                                name: s,
-                                path: join_with_double_colon(path),
-                                desc,
-                                parent,
-                                parent_idx: None,
-                                search_type: get_function_type_for_search(
-                                    &item,
-                                    self.tcx,
-                                    clean_impl_generics(self.cache.parent_stack.last()).as_ref(),
-                                    self.cache,
-                                ),
-                                aliases: item.attrs.get_doc_aliases(),
-                                deprecation: item.deprecation(self.tcx),
-                            });
-                        }
+                        // In case this is a field from a tuple struct, we don't add it into
+                        // the search index because its name is something like "0", which is
+                        // not useful for rustdoc search.
+                        self.cache.search_index.push(IndexItem {
+                            ty,
+                            name: s,
+                            path: join_with_double_colon(path),
+                            desc,
+                            parent,
+                            parent_idx: None,
+                            impl_id: if let Some(ParentStackItem::Impl { item_id, .. }) = self.cache.parent_stack.last() {
+                                item_id.as_def_id()
+                            } else {
+                                None
+                            },
+                            search_type: get_function_type_for_search(
+                                &item,
+                                self.tcx,
+                                clean_impl_generics(self.cache.parent_stack.last()).as_ref(),
+                                self.cache,
+                            ),
+                            aliases: item.attrs.get_doc_aliases(),
+                            deprecation: item.deprecation(self.tcx),
+                        });
                     }
                 }
                 (Some(parent), None) if is_inherent_impl_item => {
@@ -371,6 +374,13 @@ impl<'a, 'tcx> DocFolder for CacheBuilder<'a, 'tcx> {
                         parent,
                         item: item.clone(),
                         impl_generics,
+                        impl_id: if let Some(ParentStackItem::Impl { item_id, .. }) =
+                            self.cache.parent_stack.last()
+                        {
+                            item_id.as_def_id()
+                        } else {
+                            None
+                        },
                     });
                 }
                 _ => {}
@@ -541,6 +551,7 @@ impl<'a, 'tcx> DocFolder for CacheBuilder<'a, 'tcx> {
 
 pub(crate) struct OrphanImplItem {
     pub(crate) parent: DefId,
+    pub(crate) impl_id: Option<DefId>,
     pub(crate) item: clean::Item,
     pub(crate) impl_generics: Option<(clean::Type, clean::Generics)>,
 }
diff --git a/src/librustdoc/html/render/mod.rs b/src/librustdoc/html/render/mod.rs
index 3e671a64b54..b0ce475850c 100644
--- a/src/librustdoc/html/render/mod.rs
+++ b/src/librustdoc/html/render/mod.rs
@@ -54,7 +54,7 @@ use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir::def_id::{DefId, DefIdSet};
 use rustc_hir::Mutability;
 use rustc_middle::middle::stability;
-use rustc_middle::ty::TyCtxt;
+use rustc_middle::ty::{self, TyCtxt};
 use rustc_span::{
     symbol::{sym, Symbol},
     BytePos, FileName, RealFileName,
@@ -102,6 +102,7 @@ pub(crate) struct IndexItem {
     pub(crate) desc: String,
     pub(crate) parent: Option<DefId>,
     pub(crate) parent_idx: Option<isize>,
+    pub(crate) impl_id: Option<DefId>,
     pub(crate) search_type: Option<IndexItemFunctionType>,
     pub(crate) aliases: Box<[Symbol]>,
     pub(crate) deprecation: Option<Deprecation>,
@@ -1877,7 +1878,7 @@ pub(crate) fn render_impl_summary(
     aliases: &[String],
 ) {
     let inner_impl = i.inner_impl();
-    let id = cx.derive_id(get_id_for_impl(&inner_impl.for_, inner_impl.trait_.as_ref(), cx));
+    let id = cx.derive_id(get_id_for_impl(cx.tcx(), i.impl_item.item_id));
     let aliases = if aliases.is_empty() {
         String::new()
     } else {
@@ -1994,21 +1995,35 @@ pub(crate) fn small_url_encode(s: String) -> String {
     }
 }
 
-fn get_id_for_impl(for_: &clean::Type, trait_: Option<&clean::Path>, cx: &Context<'_>) -> String {
-    match trait_ {
-        Some(t) => small_url_encode(format!("impl-{:#}-for-{:#}", t.print(cx), for_.print(cx))),
-        None => small_url_encode(format!("impl-{:#}", for_.print(cx))),
-    }
+fn get_id_for_impl<'tcx>(tcx: TyCtxt<'tcx>, impl_id: ItemId) -> String {
+    use rustc_middle::ty::print::with_forced_trimmed_paths;
+    let (type_, trait_) = match impl_id {
+        ItemId::Auto { trait_, for_ } => {
+            let ty = tcx.type_of(for_).skip_binder();
+            (ty, Some(ty::TraitRef::new(tcx, trait_, [ty])))
+        }
+        ItemId::Blanket { impl_id, .. } | ItemId::DefId(impl_id) => {
+            match tcx.impl_subject(impl_id).skip_binder() {
+                ty::ImplSubject::Trait(trait_ref) => {
+                    (trait_ref.args[0].expect_ty(), Some(trait_ref))
+                }
+                ty::ImplSubject::Inherent(ty) => (ty, None),
+            }
+        }
+    };
+    with_forced_trimmed_paths!(small_url_encode(if let Some(trait_) = trait_ {
+        format!("impl-{trait_}-for-{type_}", trait_ = trait_.print_only_trait_path())
+    } else {
+        format!("impl-{type_}")
+    }))
 }
 
 fn extract_for_impl_name(item: &clean::Item, cx: &Context<'_>) -> Option<(String, String)> {
     match *item.kind {
-        clean::ItemKind::ImplItem(ref i) => {
-            i.trait_.as_ref().map(|trait_| {
-                // Alternative format produces no URLs,
-                // so this parameter does nothing.
-                (format!("{:#}", i.for_.print(cx)), get_id_for_impl(&i.for_, Some(trait_), cx))
-            })
+        clean::ItemKind::ImplItem(ref i) if i.trait_.is_some() => {
+            // Alternative format produces no URLs,
+            // so this parameter does nothing.
+            Some((format!("{:#}", i.for_.print(cx)), get_id_for_impl(cx.tcx(), item.item_id)))
         }
         _ => None,
     }
diff --git a/src/librustdoc/html/render/search_index.rs b/src/librustdoc/html/render/search_index.rs
index 78c443b2257..af1dab59496 100644
--- a/src/librustdoc/html/render/search_index.rs
+++ b/src/librustdoc/html/render/search_index.rs
@@ -12,7 +12,7 @@ use crate::formats::cache::{Cache, OrphanImplItem};
 use crate::formats::item_type::ItemType;
 use crate::html::format::join_with_double_colon;
 use crate::html::markdown::short_markdown_summary;
-use crate::html::render::{IndexItem, IndexItemFunctionType, RenderType, RenderTypeId};
+use crate::html::render::{self, IndexItem, IndexItemFunctionType, RenderType, RenderTypeId};
 
 /// Builds the search index from the collected metadata
 pub(crate) fn build_index<'tcx>(
@@ -26,7 +26,8 @@ pub(crate) fn build_index<'tcx>(
 
     // Attach all orphan items to the type's definition if the type
     // has since been learned.
-    for &OrphanImplItem { parent, ref item, ref impl_generics } in &cache.orphan_impl_items {
+    for &OrphanImplItem { impl_id, parent, ref item, ref impl_generics } in &cache.orphan_impl_items
+    {
         if let Some((fqp, _)) = cache.paths.get(&parent) {
             let desc = short_markdown_summary(&item.doc_value(), &item.link_names(cache));
             cache.search_index.push(IndexItem {
@@ -36,6 +37,7 @@ pub(crate) fn build_index<'tcx>(
                 desc,
                 parent: Some(parent),
                 parent_idx: None,
+                impl_id,
                 search_type: get_function_type_for_search(item, tcx, impl_generics.as_ref(), cache),
                 aliases: item.attrs.get_doc_aliases(),
                 deprecation: item.deprecation(tcx),
@@ -222,6 +224,29 @@ pub(crate) fn build_index<'tcx>(
         })
         .collect();
 
+    // Find associated items that need disambiguators
+    let mut associated_item_duplicates = FxHashMap::<(isize, ItemType, Symbol), usize>::default();
+
+    for &item in &crate_items {
+        if item.impl_id.is_some() && let Some(parent_idx) = item.parent_idx {
+            let count = associated_item_duplicates
+                .entry((parent_idx, item.ty, item.name))
+                .or_insert(0);
+            *count += 1;
+        }
+    }
+
+    let associated_item_disambiguators = crate_items
+        .iter()
+        .enumerate()
+        .filter_map(|(index, item)| {
+            let impl_id = ItemId::DefId(item.impl_id?);
+            let parent_idx = item.parent_idx?;
+            let count = *associated_item_duplicates.get(&(parent_idx, item.ty, item.name))?;
+            if count > 1 { Some((index, render::get_id_for_impl(tcx, impl_id))) } else { None }
+        })
+        .collect::<Vec<_>>();
+
     struct CrateData<'a> {
         doc: String,
         items: Vec<&'a IndexItem>,
@@ -230,6 +255,8 @@ pub(crate) fn build_index<'tcx>(
         //
         // To be noted: the `usize` elements are indexes to `items`.
         aliases: &'a BTreeMap<String, Vec<usize>>,
+        // Used when a type has more than one impl with an associated item with the same name.
+        associated_item_disambiguators: &'a Vec<(usize, String)>,
     }
 
     struct Paths {
@@ -382,6 +409,7 @@ pub(crate) fn build_index<'tcx>(
             crate_data.serialize_field("f", &functions)?;
             crate_data.serialize_field("c", &deprecated)?;
             crate_data.serialize_field("p", &paths)?;
+            crate_data.serialize_field("b", &self.associated_item_disambiguators)?;
             if has_aliases {
                 crate_data.serialize_field("a", &self.aliases)?;
             }
@@ -398,6 +426,7 @@ pub(crate) fn build_index<'tcx>(
             items: crate_items,
             paths: crate_paths,
             aliases: &aliases,
+            associated_item_disambiguators: &associated_item_disambiguators,
         })
         .expect("failed serde conversion")
         // All these `replace` calls are because we have to go through JS string for JSON content.
diff --git a/src/librustdoc/html/render/sidebar.rs b/src/librustdoc/html/render/sidebar.rs
index 76f63c6f63e..3f8b22050c8 100644
--- a/src/librustdoc/html/render/sidebar.rs
+++ b/src/librustdoc/html/render/sidebar.rs
@@ -503,8 +503,7 @@ fn sidebar_render_assoc_items(
             .iter()
             .filter_map(|it| {
                 let trait_ = it.inner_impl().trait_.as_ref()?;
-                let encoded =
-                    id_map.derive(super::get_id_for_impl(&it.inner_impl().for_, Some(trait_), cx));
+                let encoded = id_map.derive(super::get_id_for_impl(cx.tcx(), it.impl_item.item_id));
 
                 let prefix = match it.inner_impl().polarity {
                     ty::ImplPolarity::Positive | ty::ImplPolarity::Reservation => "",
diff --git a/src/librustdoc/html/static/js/main.js b/src/librustdoc/html/static/js/main.js
index eb256455b08..43c4f2b6ff5 100644
--- a/src/librustdoc/html/static/js/main.js
+++ b/src/librustdoc/html/static/js/main.js
@@ -354,6 +354,34 @@ function preLoadCss(cssUrl) {
                 expandSection(pageId);
             }
         }
+        if (savedHash.startsWith("impl-")) {
+            // impl-disambiguated links, used by the search engine
+            // format: impl-X[-for-Y]/method.WHATEVER
+            // turn this into method.WHATEVER[-NUMBER]
+            const splitAt = savedHash.indexOf("/");
+            if (splitAt !== -1) {
+                const implId = savedHash.slice(0, splitAt);
+                const assocId = savedHash.slice(splitAt + 1);
+                const implElem = document.getElementById(implId);
+                if (implElem && implElem.parentElement.tagName === "SUMMARY" &&
+                    implElem.parentElement.parentElement.tagName === "DETAILS") {
+                    onEachLazy(implElem.parentElement.parentElement.querySelectorAll(
+                        `[id^="${assocId}"]`),
+                        item => {
+                            const numbered = /([^-]+)-([0-9]+)/.exec(item.id);
+                            if (item.id === assocId || (numbered && numbered[1] === assocId)) {
+                                openParentDetails(item);
+                                item.scrollIntoView();
+                                // Let the section expand itself before trying to highlight
+                                setTimeout(() => {
+                                    window.location.replace("#" + item.id);
+                                }, 0);
+                            }
+                        }
+                    );
+                }
+            }
+        }
     }
 
     function onHashChange(ev) {
diff --git a/src/librustdoc/html/static/js/search.js b/src/librustdoc/html/static/js/search.js
index 7a282a99e9c..48c9a53a283 100644
--- a/src/librustdoc/html/static/js/search.js
+++ b/src/librustdoc/html/static/js/search.js
@@ -1752,6 +1752,7 @@ function initSearch(rawSearchIndex) {
                 type: item.type,
                 is_alias: true,
                 deprecated: item.deprecated,
+                implDisambiguator: item.implDisambiguator,
             };
         }
 
@@ -2218,7 +2219,7 @@ function initSearch(rawSearchIndex) {
             href = ROOT_PATH + name + "/index.html";
         } else if (item.parent !== undefined) {
             const myparent = item.parent;
-            let anchor = "#" + type + "." + name;
+            let anchor = type + "." + name;
             const parentType = itemTypes[myparent.ty];
             let pageType = parentType;
             let pageName = myparent.name;
@@ -2232,16 +2233,19 @@ function initSearch(rawSearchIndex) {
                 const enumName = item.path.substr(enumNameIdx + 2);
                 path = item.path.substr(0, enumNameIdx);
                 displayPath = path + "::" + enumName + "::" + myparent.name + "::";
-                anchor = "#variant." + myparent.name + ".field." + name;
+                anchor = "variant." + myparent.name + ".field." + name;
                 pageType = "enum";
                 pageName = enumName;
             } else {
                 displayPath = path + "::" + myparent.name + "::";
             }
+            if (item.implDisambiguator !== null) {
+                anchor = item.implDisambiguator + "/" + anchor;
+            }
             href = ROOT_PATH + path.replace(/::/g, "/") +
                 "/" + pageType +
                 "." + pageName +
-                ".html" + anchor;
+                ".html#" + anchor;
         } else {
             displayPath = item.path + "::";
             href = ROOT_PATH + item.path.replace(/::/g, "/") +
@@ -2727,6 +2731,10 @@ ${item.displayPath}<span class="${type}">${name}</span>\
              * Types are also represented as arrays; the first item is an index into the `p`
              * array, while the second is a list of types representing any generic parameters.
              *
+             * b[i] contains an item's impl disambiguator. This is only present if an item
+             * is defined in an impl block and, the impl block's type has more than one associated
+             * item with the same name.
+             *
              * `a` defines aliases with an Array of pairs: [name, offset], where `offset`
              * points into the n/t/d/q/i/f arrays.
              *
@@ -2746,6 +2754,7 @@ ${item.displayPath}<span class="${type}">${name}</span>\
              *   i: Array<Number>,
              *   f: Array<RawFunctionSearchType>,
              *   p: Array<Object>,
+             *   b: Array<[Number, String]>,
              *   c: Array<Number>
              * }}
              */
@@ -2766,6 +2775,7 @@ ${item.displayPath}<span class="${type}">${name}</span>\
                 id: id,
                 normalizedName: crate.indexOf("_") === -1 ? crate : crate.replace(/_/g, ""),
                 deprecated: null,
+                implDisambiguator: null,
             };
             id += 1;
             searchIndex.push(crateRow);
@@ -2789,6 +2799,8 @@ ${item.displayPath}<span class="${type}">${name}</span>\
             const itemFunctionSearchTypes = crateCorpus.f;
             // an array of (Number) indices for the deprecated items
             const deprecatedItems = new Set(crateCorpus.c);
+            // an array of (Number) indices for the deprecated items
+            const implDisambiguator = new Map(crateCorpus.b);
             // an array of [(Number) item type,
             //              (String) name]
             const paths = crateCorpus.p;
@@ -2849,6 +2861,7 @@ ${item.displayPath}<span class="${type}">${name}</span>\
                     id: id,
                     normalizedName: word.indexOf("_") === -1 ? word : word.replace(/_/g, ""),
                     deprecated: deprecatedItems.has(i),
+                    implDisambiguator: implDisambiguator.has(i) ? implDisambiguator.get(i) : null,
                 };
                 id += 1;
                 searchIndex.push(row);
diff --git a/tests/rustdoc-gui/search-result-impl-disambiguation.goml b/tests/rustdoc-gui/search-result-impl-disambiguation.goml
new file mode 100644
index 00000000000..6d12032e891
--- /dev/null
+++ b/tests/rustdoc-gui/search-result-impl-disambiguation.goml
@@ -0,0 +1,43 @@
+// ignore-tidy-linelength
+
+// Checks that, if a type has two methods with the same name, they both get
+// linked correctly.
+go-to: "file://" + |DOC_PATH| + "/test_docs/index.html"
+
+// This should link to the inherent impl
+write: (".search-input", "ZyxwvutMethodDisambiguation -> bool")
+// To be SURE that the search will be run.
+press-key: 'Enter'
+// Waiting for the search results to appear...
+wait-for: "#search-tabs"
+// Check the disambiguated link.
+assert-count: ("a.result-method", 1)
+assert-attribute: ("a.result-method", {
+    "href": "../test_docs/struct.ZyxwvutMethodDisambiguation.html#impl-ZyxwvutMethodDisambiguation/method.method_impl_disambiguation"
+})
+click: "a.result-method"
+wait-for: "#impl-ZyxwvutMethodDisambiguation"
+assert-document-property: ({
+    "URL": "struct.ZyxwvutMethodDisambiguation.html#method.method_impl_disambiguation"
+}, ENDS_WITH)
+assert: "section:target"
+
+go-to: "file://" + |DOC_PATH| + "/test_docs/index.html"
+
+// This should link to the trait impl
+write: (".search-input", "ZyxwvutMethodDisambiguation, usize -> usize")
+// To be SURE that the search will be run.
+press-key: 'Enter'
+// Waiting for the search results to appear...
+wait-for: "#search-tabs"
+// Check the disambiguated link.
+assert-count: ("a.result-method", 1)
+assert-attribute: ("a.result-method", {
+    "href": "../test_docs/struct.ZyxwvutMethodDisambiguation.html#impl-ZyxwvutTrait-for-ZyxwvutMethodDisambiguation/method.method_impl_disambiguation"
+})
+click: "a.result-method"
+wait-for: "#impl-ZyxwvutMethodDisambiguation"
+assert-document-property: ({
+    "URL": "struct.ZyxwvutMethodDisambiguation.html#method.method_impl_disambiguation-1"
+}, ENDS_WITH)
+assert: "section:target"
diff --git a/tests/rustdoc-gui/src/test_docs/lib.rs b/tests/rustdoc-gui/src/test_docs/lib.rs
index 38180aef762..5c91bcbb4ee 100644
--- a/tests/rustdoc-gui/src/test_docs/lib.rs
+++ b/tests/rustdoc-gui/src/test_docs/lib.rs
@@ -529,3 +529,21 @@ pub mod cfgs {
     /// Some docs.
     pub mod cfgs {}
 }
+
+pub struct ZyxwvutMethodDisambiguation;
+
+impl ZyxwvutMethodDisambiguation {
+    pub fn method_impl_disambiguation(&self) -> bool {
+        true
+    }
+}
+
+pub trait ZyxwvutTrait {
+    fn method_impl_disambiguation(&self, x: usize) -> usize;
+}
+
+impl ZyxwvutTrait for ZyxwvutMethodDisambiguation {
+    fn method_impl_disambiguation(&self, x: usize) -> usize {
+        x
+    }
+}
diff --git a/tests/rustdoc-js-std/simd-type-signatures.js b/tests/rustdoc-js-std/simd-type-signatures.js
new file mode 100644
index 00000000000..5c7cf372bce
--- /dev/null
+++ b/tests/rustdoc-js-std/simd-type-signatures.js
@@ -0,0 +1,70 @@
+// exact-check
+// ignore-order
+// ignore-tidy-linelength
+
+// This test case verifies that the href points at the correct impl
+
+const FILTER_CRATE = "std";
+
+const EXPECTED = [
+    {
+        'query': 'simd<i16>, simd<i16> -> simd<i16>',
+        'others': [
+            {
+                'path': 'std::simd::prelude::Simd',
+                'name': 'simd_max',
+                'href': '../std/simd/prelude/struct.Simd.html#impl-SimdOrd-for-Simd%3Ci16,+LANES%3E/method.simd_max'
+            },
+            {
+                'path': 'std::simd::prelude::Simd',
+                'name': 'simd_min',
+                'href': '../std/simd/prelude/struct.Simd.html#impl-SimdOrd-for-Simd%3Ci16,+LANES%3E/method.simd_min'
+            },
+            {
+                'path': 'std::simd::prelude::Simd',
+                'name': 'simd_clamp',
+                'href': '../std/simd/prelude/struct.Simd.html#impl-SimdOrd-for-Simd%3Ci16,+LANES%3E/method.simd_clamp'
+            },
+            {
+                'path': 'std::simd::prelude::Simd',
+                'name': 'saturating_add',
+                'href': '../std/simd/prelude/struct.Simd.html#impl-SimdInt-for-Simd%3Ci16,+LANES%3E/method.saturating_add'
+            },
+            {
+                'path': 'std::simd::prelude::Simd',
+                'name': 'saturating_sub',
+                'href': '../std/simd/prelude/struct.Simd.html#impl-SimdInt-for-Simd%3Ci16,+LANES%3E/method.saturating_sub'
+            },
+        ],
+    },
+    {
+        'query': 'simd<i8>, simd<i8> -> simd<i8>',
+        'others': [
+            {
+                'path': 'std::simd::prelude::Simd',
+                'name': 'simd_max',
+                'href': '../std/simd/prelude/struct.Simd.html#impl-SimdOrd-for-Simd%3Ci8,+LANES%3E/method.simd_max'
+            },
+            {
+                'path': 'std::simd::prelude::Simd',
+                'name': 'simd_min',
+                'href': '../std/simd/prelude/struct.Simd.html#impl-SimdOrd-for-Simd%3Ci8,+LANES%3E/method.simd_min'
+            },
+            {
+                'path': 'std::simd::prelude::Simd',
+                'name': 'simd_clamp',
+                'href': '../std/simd/prelude/struct.Simd.html#impl-SimdOrd-for-Simd%3Ci8,+LANES%3E/method.simd_clamp'
+            },
+            {
+                'path': 'std::simd::prelude::Simd',
+                'name': 'saturating_add',
+                'href': '../std/simd/prelude/struct.Simd.html#impl-SimdInt-for-Simd%3Ci8,+LANES%3E/method.saturating_add'
+            },
+            {
+                'path': 'std::simd::prelude::Simd',
+                'name': 'saturating_sub',
+                'href': '../std/simd/prelude/struct.Simd.html#impl-SimdInt-for-Simd%3Ci8,+LANES%3E/method.saturating_sub'
+            },
+        ],
+    },
+];
diff --git a/tests/rustdoc-js/search-method-disambiguate.js b/tests/rustdoc-js/search-method-disambiguate.js
new file mode 100644
index 00000000000..70aa895f994
--- /dev/null
+++ b/tests/rustdoc-js/search-method-disambiguate.js
@@ -0,0 +1,28 @@
+// exact-check
+// ignore-order
+// ignore-tidy-linelength
+
+const FILTER_CRATE = "search_method_disambiguate";
+
+const EXPECTED = [
+    {
+        'query': 'MyTy -> bool',
+        'others': [
+            {
+                'path': 'search_method_disambiguate::MyTy',
+                'name': 'my_method',
+                'href': '../search_method_disambiguate/struct.MyTy.html#impl-X-for-MyTy%3Cbool%3E/method.my_method'
+            },
+        ],
+    },
+    {
+        'query': 'MyTy -> u8',
+        'others': [
+            {
+                'path': 'search_method_disambiguate::MyTy',
+                'name': 'my_method',
+                'href': '../search_method_disambiguate/struct.MyTy.html#impl-X-for-MyTy%3Cu8%3E/method.my_method'
+            },
+        ],
+    }
+];
diff --git a/tests/rustdoc-js/search-method-disambiguate.rs b/tests/rustdoc-js/search-method-disambiguate.rs
new file mode 100644
index 00000000000..ae884447a92
--- /dev/null
+++ b/tests/rustdoc-js/search-method-disambiguate.rs
@@ -0,0 +1,22 @@
+pub trait X {
+    type InnerType;
+    fn my_method(&self) -> Self::InnerType;
+}
+
+pub struct MyTy<T> {
+    pub t: T,
+}
+
+impl X for MyTy<bool> {
+    type InnerType = bool;
+    fn my_method(&self) -> bool {
+        self.t
+    }
+}
+
+impl X for MyTy<u8> {
+    type InnerType = u8;
+    fn my_method(&self) -> u8 {
+        self.t
+    }
+}
diff --git a/tests/rustdoc/blanket-reexport-item.rs b/tests/rustdoc/blanket-reexport-item.rs
index 437f0001fcf..315a38c30c5 100644
--- a/tests/rustdoc/blanket-reexport-item.rs
+++ b/tests/rustdoc/blanket-reexport-item.rs
@@ -1,6 +1,6 @@
 #![crate_name = "foo"]
 
-// @has foo/struct.S.html '//*[@id="impl-Into%3CU%3E-for-S"]//h3[@class="code-header"]' 'impl<T, U> Into<U> for T'
+// @has foo/struct.S.html '//*[@id="impl-Into%3CU%3E-for-T"]//h3[@class="code-header"]' 'impl<T, U> Into<U> for T'
 pub struct S2 {}
 mod m {
     pub struct S {}
diff --git a/tests/rustdoc/const-generics/const-impl.rs b/tests/rustdoc/const-generics/const-impl.rs
index 152b643bf4b..b424ea4b33c 100644
--- a/tests/rustdoc/const-generics/const-impl.rs
+++ b/tests/rustdoc/const-generics/const-impl.rs
@@ -31,7 +31,7 @@ impl<T> VSet<T, { Order::Unsorted }> {
 
 pub struct Escape<const S: &'static str>;
 
-// @has foo/struct.Escape.html '//*[@id="impl-Escape%3Cr%23%22%3Cscript%3Ealert(%22Escape%22);%3C/script%3E%22%23%3E"]/h3[@class="code-header"]' 'impl Escape<r#"<script>alert("Escape");</script>"#>'
+// @has foo/struct.Escape.html '//*[@id="impl-Escape%3C%22%3Cscript%3Ealert(%5C%22Escape%5C%22);%3C/script%3E%22%3E"]/h3[@class="code-header"]' 'impl Escape<r#"<script>alert("Escape");</script>"#>'
 impl Escape<r#"<script>alert("Escape");</script>"#> {
     pub fn f() {}
 }
diff --git a/tests/rustdoc/generic-impl.rs b/tests/rustdoc/generic-impl.rs
index 6f68b157499..f62540c6bf9 100644
--- a/tests/rustdoc/generic-impl.rs
+++ b/tests/rustdoc/generic-impl.rs
@@ -5,9 +5,9 @@ use std::fmt;
 // @!has foo/struct.Bar.html '//*[@id="impl-ToString-for-Bar"]' ''
 pub struct Bar;
 
-// @has foo/struct.Foo.html '//*[@id="impl-ToString-for-Foo"]//h3[@class="code-header"]' 'impl<T> ToString for T'
+// @has foo/struct.Foo.html '//*[@id="impl-ToString-for-T"]//h3[@class="code-header"]' 'impl<T> ToString for T'
 pub struct Foo;
-// @has foo/struct.Foo.html '//*[@class="sidebar-elems"]//section//a[@href="#impl-ToString-for-Foo"]' 'ToString'
+// @has foo/struct.Foo.html '//*[@class="sidebar-elems"]//section//a[@href="#impl-ToString-for-T"]' 'ToString'
 
 impl fmt::Display for Foo {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
diff --git a/tests/rustdoc/issue-32077-type-alias-impls.rs b/tests/rustdoc/issue-32077-type-alias-impls.rs
index ac486c36ad0..664b678093e 100644
--- a/tests/rustdoc/issue-32077-type-alias-impls.rs
+++ b/tests/rustdoc/issue-32077-type-alias-impls.rs
@@ -22,7 +22,7 @@ impl Bar for GenericStruct<u32> {}
 // We check that "Aliased type" is also present as a title in the sidebar.
 // @has - '//*[@class="sidebar-elems"]//h3/a[@href="#aliased-type"]' 'Aliased type'
 // We check that we have the implementation of the type alias itself.
-// @has - '//*[@id="impl-TypedefStruct"]/h3' 'impl TypedefStruct'
+// @has - '//*[@id="impl-GenericStruct%3Cu8%3E"]/h3' 'impl TypedefStruct'
 // @has - '//*[@id="method.on_alias"]/h4' 'pub fn on_alias()'
 // @has - '//*[@id="impl-GenericStruct%3CT%3E"]/h3' 'impl<T> GenericStruct<T>'
 // @has - '//*[@id="method.on_gen"]/h4' 'pub fn on_gen(arg: T)'
diff --git a/tests/rustdoc/issue-78701.rs b/tests/rustdoc/issue-78701.rs
index e3e46468f38..3f1638d5ffc 100644
--- a/tests/rustdoc/issue-78701.rs
+++ b/tests/rustdoc/issue-78701.rs
@@ -6,7 +6,7 @@
 
 // @has 'foo/struct.AnotherStruct.html'
 // @count - '//*[@class="sidebar"]//a[@href="#impl-AnAmazingTrait-for-AnotherStruct%3C()%3E"]' 1
-// @count - '//*[@class="sidebar"]//a[@href="#impl-AnAmazingTrait-for-AnotherStruct%3CT%3E"]' 1
+// @count - '//*[@class="sidebar"]//a[@href="#impl-AnAmazingTrait-for-T"]' 1
 
 pub trait Something {}
 
diff --git a/tests/rustdoc/primitive/primitive-generic-impl.rs b/tests/rustdoc/primitive/primitive-generic-impl.rs
index 2da8ae6ff38..558336d7316 100644
--- a/tests/rustdoc/primitive/primitive-generic-impl.rs
+++ b/tests/rustdoc/primitive/primitive-generic-impl.rs
@@ -1,7 +1,7 @@
 #![feature(rustc_attrs)]
 #![crate_name = "foo"]
 
-// @has foo/primitive.i32.html '//*[@id="impl-ToString-for-i32"]//h3[@class="code-header"]' 'impl<T> ToString for T'
+// @has foo/primitive.i32.html '//*[@id="impl-ToString-for-T"]//h3[@class="code-header"]' 'impl<T> ToString for T'
 
 #[rustc_doc_primitive = "i32"]
 /// Some useless docs, wouhou!
diff --git a/tests/rustdoc/sidebar-links-to-foreign-impl.rs b/tests/rustdoc/sidebar-links-to-foreign-impl.rs
index caa17dfbb1c..733a18ad94a 100644
--- a/tests/rustdoc/sidebar-links-to-foreign-impl.rs
+++ b/tests/rustdoc/sidebar-links-to-foreign-impl.rs
@@ -7,8 +7,8 @@
 // @has - '//h2[@id="foreign-impls"]' 'Implementations on Foreign Types'
 // @has - '//*[@class="sidebar-elems"]//section//a[@href="#impl-Foo-for-u32"]' 'u32'
 // @has - '//*[@id="impl-Foo-for-u32"]//h3[@class="code-header"]' 'impl Foo for u32'
-// @has - "//*[@class=\"sidebar-elems\"]//section//a[@href=\"#impl-Foo-for-%26'a+str\"]" "&'a str"
-// @has - "//*[@id=\"impl-Foo-for-%26'a+str\"]//h3[@class=\"code-header\"]" "impl<'a> Foo for &'a str"
+// @has - "//*[@class=\"sidebar-elems\"]//section//a[@href=\"#impl-Foo-for-%26str\"]" "&'a str"
+// @has - "//*[@id=\"impl-Foo-for-%26str\"]//h3[@class=\"code-header\"]" "impl<'a> Foo for &'a str"
 pub trait Foo {}
 
 impl Foo for u32 {}
diff --git a/tests/rustdoc/src-links-auto-impls.rs b/tests/rustdoc/src-links-auto-impls.rs
index 1c8d1573192..08a497d4cf5 100644
--- a/tests/rustdoc/src-links-auto-impls.rs
+++ b/tests/rustdoc/src-links-auto-impls.rs
@@ -5,8 +5,8 @@
 // @!has - '//*[@id="impl-Sized-for-Unsized"]//a[@class="src"]' 'source'
 // @has - '//*[@id="impl-Sync-for-Unsized"]/h3[@class="code-header"]' 'impl Sync for Unsized'
 // @!has - '//*[@id="impl-Sync-for-Unsized"]//a[@class="src"]' 'source'
-// @has - '//*[@id="impl-Any-for-Unsized"]/h3[@class="code-header"]' 'impl<T> Any for T'
-// @has - '//*[@id="impl-Any-for-Unsized"]//a[@class="src rightside"]' 'source'
+// @has - '//*[@id="impl-Any-for-T"]/h3[@class="code-header"]' 'impl<T> Any for T'
+// @has - '//*[@id="impl-Any-for-T"]//a[@class="src rightside"]' 'source'
 pub struct Unsized {
     data: [u8],
 }
diff --git a/tests/rustdoc/where-clause-order.rs b/tests/rustdoc/where-clause-order.rs
index b10f8f6856e..7261dfa7dd9 100644
--- a/tests/rustdoc/where-clause-order.rs
+++ b/tests/rustdoc/where-clause-order.rs
@@ -7,7 +7,7 @@ where
 }
 
 // @has 'foo/trait.SomeTrait.html'
-// @has - "//*[@id='impl-SomeTrait%3C(A,+B,+C,+D,+E)%3E-for-(A,+B,+C,+D,+E)']/h3" "impl<A, B, C, D, E> SomeTrait<(A, B, C, D, E)> for (A, B, C, D, E)where A: PartialOrd<A> + PartialEq<A>, B: PartialOrd<B> + PartialEq<B>, C: PartialOrd<C> + PartialEq<C>, D: PartialOrd<D> + PartialEq<D>, E: PartialOrd<E> + PartialEq<E> + ?Sized, "
+// @has - "//*[@id='impl-SomeTrait-for-(A,+B,+C,+D,+E)']/h3" "impl<A, B, C, D, E> SomeTrait<(A, B, C, D, E)> for (A, B, C, D, E)where A: PartialOrd<A> + PartialEq<A>, B: PartialOrd<B> + PartialEq<B>, C: PartialOrd<C> + PartialEq<C>, D: PartialOrd<D> + PartialEq<D>, E: PartialOrd<E> + PartialEq<E> + ?Sized, "
 impl<A, B, C, D, E> SomeTrait<(A, B, C, D, E)> for (A, B, C, D, E)
 where
     A: PartialOrd<A> + PartialEq<A>,
@@ -17,3 +17,14 @@ where
     E: PartialOrd<E> + PartialEq<E> + ?Sized,
 {
 }
+
+// @has - "//*[@id='impl-SomeTrait%3C(A,+B,+C,+D)%3E-for-(A,+B,+C,+D,+E)']/h3" "impl<A, B, C, D, E> SomeTrait<(A, B, C, D)> for (A, B, C, D, E)where A: PartialOrd<A> + PartialEq<A>, B: PartialOrd<B> + PartialEq<B>, C: PartialOrd<C> + PartialEq<C>, D: PartialOrd<D> + PartialEq<D>, E: PartialOrd<E> + PartialEq<E> + ?Sized, "
+impl<A, B, C, D, E> SomeTrait<(A, B, C, D)> for (A, B, C, D, E)
+where
+    A: PartialOrd<A> + PartialEq<A>,
+    B: PartialOrd<B> + PartialEq<B>,
+    C: PartialOrd<C> + PartialEq<C>,
+    D: PartialOrd<D> + PartialEq<D>,
+    E: PartialOrd<E> + PartialEq<E> + ?Sized,
+{
+}
diff --git a/tests/ui/consts/const-eval/unused-broken-const-late.rs b/tests/ui/consts/const-eval/unused-broken-const-late.rs
new file mode 100644
index 00000000000..a6528ec5fd6
--- /dev/null
+++ b/tests/ui/consts/const-eval/unused-broken-const-late.rs
@@ -0,0 +1,20 @@
+// build-fail
+// compile-flags: -O
+//! Make sure we detect erroneous constants post-monomorphization even when they are unused. This is
+//! crucial, people rely on it for soundness. (https://github.com/rust-lang/rust/issues/112090)
+
+struct PrintName<T>(T);
+impl<T> PrintName<T> {
+    const VOID: () = panic!(); //~ERROR evaluation of `PrintName::<i32>::VOID` failed
+}
+
+fn no_codegen<T>() {
+    // Any function that is called is guaranteed to have all consts that syntactically
+    // appear in its body evaluated, even if they only appear in dead code.
+    if false {
+        let _ = PrintName::<T>::VOID;
+    }
+}
+pub fn main() {
+    no_codegen::<i32>();
+}
diff --git a/tests/ui/consts/const-eval/unused-broken-const-late.stderr b/tests/ui/consts/const-eval/unused-broken-const-late.stderr
new file mode 100644
index 00000000000..cdb70a69dfd
--- /dev/null
+++ b/tests/ui/consts/const-eval/unused-broken-const-late.stderr
@@ -0,0 +1,11 @@
+error[E0080]: evaluation of `PrintName::<i32>::VOID` failed
+  --> $DIR/unused-broken-const-late.rs:8:22
+   |
+LL |     const VOID: () = panic!();
+   |                      ^^^^^^^^ the evaluated program panicked at 'explicit panic', $DIR/unused-broken-const-late.rs:8:22
+   |
+   = note: this error originates in the macro `$crate::panic::panic_2015` which comes from the expansion of the macro `panic` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0080`.
diff --git a/tests/ui/unboxed-closures/unboxed-closures-type-mismatch.rs b/tests/ui/unboxed-closures/unboxed-closures-type-mismatch.rs
index 9f76849e5fb..0999f61b01a 100644
--- a/tests/ui/unboxed-closures/unboxed-closures-type-mismatch.rs
+++ b/tests/ui/unboxed-closures/unboxed-closures-type-mismatch.rs
@@ -1,7 +1,35 @@
 use std::ops::FnMut;
 
-pub fn main() {
+fn main() {
     let mut f = |x: isize, y: isize| -> isize { x + y };
-    let z = f(1_usize, 2);    //~ ERROR mismatched types
+    let z = f(1_usize, 2); //~ ERROR mismatched types
     println!("{}", z);
+    let mut g = |x, y| { x + y };
+    let y = g(1_i32, 2);
+    let z = g(1_usize, 2); //~ ERROR mismatched types
+    println!("{}", z);
+}
+
+trait T {
+    fn bar(&self) {
+        let identity = |x| x;
+        identity(1u8);
+        identity(1u16); //~ ERROR mismatched types
+        let identity = |x| x;
+        identity(&1u8);
+        identity(&1u16); //~ ERROR mismatched types
+    }
+}
+
+struct S;
+
+impl T  for S {
+    fn bar(&self) {
+        let identity = |x| x;
+        identity(1u8);
+        identity(1u16); //~ ERROR mismatched types
+        let identity = |x| x;
+        identity(&1u8);
+        identity(&1u16); //~ ERROR mismatched types
+    }
 }
diff --git a/tests/ui/unboxed-closures/unboxed-closures-type-mismatch.stderr b/tests/ui/unboxed-closures/unboxed-closures-type-mismatch.stderr
index 455f83f5721..327df50e645 100644
--- a/tests/ui/unboxed-closures/unboxed-closures-type-mismatch.stderr
+++ b/tests/ui/unboxed-closures/unboxed-closures-type-mismatch.stderr
@@ -16,6 +16,127 @@ help: change the type of the numeric literal from `usize` to `isize`
 LL |     let z = f(1_isize, 2);
    |                 ~~~~~
 
-error: aborting due to previous error
+error[E0308]: mismatched types
+  --> $DIR/unboxed-closures-type-mismatch.rs:9:15
+   |
+LL |     let z = g(1_usize, 2);
+   |             - ^^^^^^^ expected `i32`, found `usize`
+   |             |
+   |             arguments to this function are incorrect
+   |
+note: expected because the closure was earlier called with an argument of type `i32`
+  --> $DIR/unboxed-closures-type-mismatch.rs:8:15
+   |
+LL |     let y = g(1_i32, 2);
+   |             - ^^^^^ expected because this argument is of type `i32`
+   |             |
+   |             in this closure call
+note: closure parameter defined here
+  --> $DIR/unboxed-closures-type-mismatch.rs:7:18
+   |
+LL |     let mut g = |x, y| { x + y };
+   |                  ^
+help: change the type of the numeric literal from `usize` to `i32`
+   |
+LL |     let z = g(1_i32, 2);
+   |                 ~~~
+
+error[E0308]: mismatched types
+  --> $DIR/unboxed-closures-type-mismatch.rs:17:18
+   |
+LL |         identity(1u16);
+   |         -------- ^^^^ expected `u8`, found `u16`
+   |         |
+   |         arguments to this function are incorrect
+   |
+note: expected because the closure was earlier called with an argument of type `u8`
+  --> $DIR/unboxed-closures-type-mismatch.rs:16:18
+   |
+LL |         identity(1u8);
+   |         -------- ^^^ expected because this argument is of type `u8`
+   |         |
+   |         in this closure call
+note: closure parameter defined here
+  --> $DIR/unboxed-closures-type-mismatch.rs:15:25
+   |
+LL |         let identity = |x| x;
+   |                         ^
+help: change the type of the numeric literal from `u16` to `u8`
+   |
+LL |         identity(1u8);
+   |                   ~~
+
+error[E0308]: mismatched types
+  --> $DIR/unboxed-closures-type-mismatch.rs:20:18
+   |
+LL |         identity(&1u16);
+   |         -------- ^^^^^ expected `&u8`, found `&u16`
+   |         |
+   |         arguments to this function are incorrect
+   |
+   = note: expected reference `&u8`
+              found reference `&u16`
+note: expected because the closure was earlier called with an argument of type `&u8`
+  --> $DIR/unboxed-closures-type-mismatch.rs:19:18
+   |
+LL |         identity(&1u8);
+   |         -------- ^^^^ expected because this argument is of type `&u8`
+   |         |
+   |         in this closure call
+note: closure parameter defined here
+  --> $DIR/unboxed-closures-type-mismatch.rs:18:25
+   |
+LL |         let identity = |x| x;
+   |                         ^
+
+error[E0308]: mismatched types
+  --> $DIR/unboxed-closures-type-mismatch.rs:30:18
+   |
+LL |         identity(1u16);
+   |         -------- ^^^^ expected `u8`, found `u16`
+   |         |
+   |         arguments to this function are incorrect
+   |
+note: expected because the closure was earlier called with an argument of type `u8`
+  --> $DIR/unboxed-closures-type-mismatch.rs:29:18
+   |
+LL |         identity(1u8);
+   |         -------- ^^^ expected because this argument is of type `u8`
+   |         |
+   |         in this closure call
+note: closure parameter defined here
+  --> $DIR/unboxed-closures-type-mismatch.rs:28:25
+   |
+LL |         let identity = |x| x;
+   |                         ^
+help: change the type of the numeric literal from `u16` to `u8`
+   |
+LL |         identity(1u8);
+   |                   ~~
+
+error[E0308]: mismatched types
+  --> $DIR/unboxed-closures-type-mismatch.rs:33:18
+   |
+LL |         identity(&1u16);
+   |         -------- ^^^^^ expected `&u8`, found `&u16`
+   |         |
+   |         arguments to this function are incorrect
+   |
+   = note: expected reference `&u8`
+              found reference `&u16`
+note: expected because the closure was earlier called with an argument of type `&u8`
+  --> $DIR/unboxed-closures-type-mismatch.rs:32:18
+   |
+LL |         identity(&1u8);
+   |         -------- ^^^^ expected because this argument is of type `&u8`
+   |         |
+   |         in this closure call
+note: closure parameter defined here
+  --> $DIR/unboxed-closures-type-mismatch.rs:31:25
+   |
+LL |         let identity = |x| x;
+   |                         ^
+
+error: aborting due to 6 previous errors
 
 For more information about this error, try `rustc --explain E0308`.