diff --git a/compiler/rustc_ast_passes/src/ast_validation.rs b/compiler/rustc_ast_passes/src/ast_validation.rs
index 7865c523f758c..6e5ba556ef079 100644
--- a/compiler/rustc_ast_passes/src/ast_validation.rs
+++ b/compiler/rustc_ast_passes/src/ast_validation.rs
@@ -252,20 +252,6 @@ impl<'a> AstValidator<'a> {
         }
     }
 
-    fn visit_struct_field_def(&mut self, field: &'a FieldDef) {
-        if let Some(ident) = field.ident {
-            if ident.name == kw::Underscore {
-                self.visit_vis(&field.vis);
-                self.visit_ident(ident);
-                self.visit_ty_common(&field.ty);
-                self.walk_ty(&field.ty);
-                walk_list!(self, visit_attribute, &field.attrs);
-                return;
-            }
-        }
-        self.visit_field_def(field);
-    }
-
     fn err_handler(&self) -> &rustc_errors::Handler {
         &self.session.diagnostic()
     }
@@ -1006,8 +992,8 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
         visit::walk_lifetime(self, lifetime);
     }
 
-    fn visit_field_def(&mut self, s: &'a FieldDef) {
-        visit::walk_field_def(self, s)
+    fn visit_field_def(&mut self, field: &'a FieldDef) {
+        visit::walk_field_def(self, field)
     }
 
     fn visit_item(&mut self, item: &'a Item) {
@@ -1195,42 +1181,10 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
                     self.check_mod_file_item_asciionly(item.ident);
                 }
             }
-            ItemKind::Struct(ref vdata, ref generics) => match vdata {
-                // Duplicating the `Visitor` logic allows catching all cases
-                // of `Anonymous(Struct, Union)` outside of a field struct or union.
-                //
-                // Inside `visit_ty` the validator catches every `Anonymous(Struct, Union)` it
-                // encounters, and only on `ItemKind::Struct` and `ItemKind::Union`
-                // it uses `visit_ty_common`, which doesn't contain that specific check.
-                VariantData::Struct(ref fields, ..) => {
-                    self.visit_vis(&item.vis);
-                    self.visit_ident(item.ident);
-                    self.visit_generics(generics);
-                    self.with_banned_assoc_ty_bound(|this| {
-                        walk_list!(this, visit_struct_field_def, fields);
-                    });
-                    walk_list!(self, visit_attribute, &item.attrs);
-                    return;
-                }
-                _ => {}
-            },
-            ItemKind::Union(ref vdata, ref generics) => {
+            ItemKind::Union(ref vdata, ..) => {
                 if vdata.fields().is_empty() {
                     self.err_handler().span_err(item.span, "unions cannot have zero fields");
                 }
-                match vdata {
-                    VariantData::Struct(ref fields, ..) => {
-                        self.visit_vis(&item.vis);
-                        self.visit_ident(item.ident);
-                        self.visit_generics(generics);
-                        self.with_banned_assoc_ty_bound(|this| {
-                            walk_list!(this, visit_struct_field_def, fields);
-                        });
-                        walk_list!(self, visit_attribute, &item.attrs);
-                        return;
-                    }
-                    _ => {}
-                }
             }
             ItemKind::Const(def, .., None) => {
                 self.check_defaultness(item.span, def);
diff --git a/compiler/rustc_data_structures/src/sso/set.rs b/compiler/rustc_data_structures/src/sso/set.rs
index 4fda3adb7b878..406f0270dcc1b 100644
--- a/compiler/rustc_data_structures/src/sso/set.rs
+++ b/compiler/rustc_data_structures/src/sso/set.rs
@@ -27,7 +27,7 @@ pub struct SsoHashSet<T> {
     map: SsoHashMap<T, ()>,
 }
 
-/// Adapter function used ot return
+/// Adapter function used to return
 /// result if SsoHashMap functions into
 /// result SsoHashSet should return.
 #[inline(always)]
diff --git a/compiler/rustc_hir_analysis/src/check/dropck.rs b/compiler/rustc_hir_analysis/src/check/dropck.rs
index e5b212eb757b6..3d55ffc595f53 100644
--- a/compiler/rustc_hir_analysis/src/check/dropck.rs
+++ b/compiler/rustc_hir_analysis/src/check/dropck.rs
@@ -184,13 +184,7 @@ fn ensure_drop_predicates_are_implied_by_item_defn<'tcx>(
             let p = p.kind();
             match (predicate.skip_binder(), p.skip_binder()) {
                 (ty::PredicateKind::Trait(a), ty::PredicateKind::Trait(b)) => {
-                    // Since struct predicates cannot have ~const, project the impl predicate
-                    // onto one that ignores the constness. This is equivalent to saying that
-                    // we match a `Trait` bound on the struct with a `Trait` or `~const Trait`
-                    // in the impl.
-                    let non_const_a =
-                        ty::TraitPredicate { constness: ty::BoundConstness::NotConst, ..a };
-                    relator.relate(predicate.rebind(non_const_a), p.rebind(b)).is_ok()
+                    relator.relate(predicate.rebind(a), p.rebind(b)).is_ok()
                 }
                 (ty::PredicateKind::Projection(a), ty::PredicateKind::Projection(b)) => {
                     relator.relate(predicate.rebind(a), p.rebind(b)).is_ok()
diff --git a/compiler/rustc_lint_defs/src/builtin.rs b/compiler/rustc_lint_defs/src/builtin.rs
index d6cc31331a3bc..61ee467f59577 100644
--- a/compiler/rustc_lint_defs/src/builtin.rs
+++ b/compiler/rustc_lint_defs/src/builtin.rs
@@ -1427,6 +1427,7 @@ declare_lint! {
     "trait-object types were treated as different depending on marker-trait order",
     @future_incompatible = FutureIncompatibleInfo {
         reference: "issue #56484 <https://github.com/rust-lang/rust/issues/56484>",
+        reason: FutureIncompatibilityReason::FutureReleaseErrorReportNow,
     };
 }
 
diff --git a/compiler/rustc_middle/src/mir/interpret/queries.rs b/compiler/rustc_middle/src/mir/interpret/queries.rs
index 8f67161420dad..a7e86141a04ee 100644
--- a/compiler/rustc_middle/src/mir/interpret/queries.rs
+++ b/compiler/rustc_middle/src/mir/interpret/queries.rs
@@ -51,7 +51,7 @@ impl<'tcx> TyCtxt<'tcx> {
 
         match ty::Instance::resolve_opt_const_arg(
             self, param_env,
-            // FIXME: maybe have a seperate version for resolving mir::UnevaluatedConst?
+            // FIXME: maybe have a separate version for resolving mir::UnevaluatedConst?
             ct.def, ct.substs,
         ) {
             Ok(Some(instance)) => {
diff --git a/compiler/rustc_resolve/src/late.rs b/compiler/rustc_resolve/src/late.rs
index ba3d8f64bbc76..58853346a9288 100644
--- a/compiler/rustc_resolve/src/late.rs
+++ b/compiler/rustc_resolve/src/late.rs
@@ -524,6 +524,9 @@ struct DiagnosticMetadata<'ast> {
     /// Used to detect possible `if let` written without `let` and to provide structured suggestion.
     in_if_condition: Option<&'ast Expr>,
 
+    /// Used to detect possible new binding written without `let` and to provide structured suggestion.
+    in_assignment: Option<&'ast Expr>,
+
     /// If we are currently in a trait object definition. Used to point at the bounds when
     /// encountering a struct or enum.
     current_trait_object: Option<&'ast [ast::GenericBound]>,
@@ -3905,6 +3908,11 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
                 self.resolve_expr(elem, Some(expr));
                 self.visit_expr(idx);
             }
+            ExprKind::Assign(..) => {
+                let old = self.diagnostic_metadata.in_assignment.replace(expr);
+                visit::walk_expr(self, expr);
+                self.diagnostic_metadata.in_assignment = old;
+            }
             _ => {
                 visit::walk_expr(self, expr);
             }
diff --git a/compiler/rustc_resolve/src/late/diagnostics.rs b/compiler/rustc_resolve/src/late/diagnostics.rs
index e3dba2366a40e..23c5fac8b71c1 100644
--- a/compiler/rustc_resolve/src/late/diagnostics.rs
+++ b/compiler/rustc_resolve/src/late/diagnostics.rs
@@ -708,7 +708,9 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
 
             // If the trait has a single item (which wasn't matched by Levenshtein), suggest it
             let suggestion = self.get_single_associated_item(&path, &source, is_expected);
-            self.r.add_typo_suggestion(err, suggestion, ident_span);
+            if !self.r.add_typo_suggestion(err, suggestion, ident_span) {
+                fallback = !self.let_binding_suggestion(err, ident_span);
+            }
         }
         fallback
     }
@@ -1105,41 +1107,14 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
         // where a brace being opened means a block is being started. Look
         // ahead for the next text to see if `span` is followed by a `{`.
         let sm = self.r.session.source_map();
-        let mut sp = span;
-        loop {
-            sp = sm.next_point(sp);
-            match sm.span_to_snippet(sp) {
-                Ok(ref snippet) => {
-                    if snippet.chars().any(|c| !c.is_whitespace()) {
-                        break;
-                    }
-                }
-                _ => break,
-            }
-        }
+        let sp = sm.span_look_ahead(span, None, Some(50));
         let followed_by_brace = matches!(sm.span_to_snippet(sp), Ok(ref snippet) if snippet == "{");
         // In case this could be a struct literal that needs to be surrounded
         // by parentheses, find the appropriate span.
-        let mut i = 0;
-        let mut closing_brace = None;
-        loop {
-            sp = sm.next_point(sp);
-            match sm.span_to_snippet(sp) {
-                Ok(ref snippet) => {
-                    if snippet == "}" {
-                        closing_brace = Some(span.to(sp));
-                        break;
-                    }
-                }
-                _ => break,
-            }
-            i += 1;
-            // The bigger the span, the more likely we're incorrect --
-            // bound it to 100 chars long.
-            if i > 100 {
-                break;
-            }
-        }
+        let closing_span = sm.span_look_ahead(span, Some("}"), Some(50));
+        let closing_brace: Option<Span> = sm
+            .span_to_snippet(closing_span)
+            .map_or(None, |s| if s == "}" { Some(span.to(closing_span)) } else { None });
         (followed_by_brace, closing_brace)
     }
 
@@ -1779,26 +1754,16 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
                             }
                         }
                         if let Ok(base_snippet) = base_snippet {
-                            let mut sp = after_colon_sp;
-                            for _ in 0..100 {
-                                // Try to find an assignment
-                                sp = sm.next_point(sp);
-                                let snippet = sm.span_to_snippet(sp);
-                                match snippet {
-                                    Ok(ref x) if x.as_str() == "=" => {
-                                        err.span_suggestion(
-                                            base_span,
-                                            "maybe you meant to write an assignment here",
-                                            format!("let {}", base_snippet),
-                                            Applicability::MaybeIncorrect,
-                                        );
-                                        show_label = false;
-                                        break;
-                                    }
-                                    Ok(ref x) if x.as_str() == "\n" => break,
-                                    Err(_) => break,
-                                    Ok(_) => {}
-                                }
+                            // Try to find an assignment
+                            let eq_span = sm.span_look_ahead(after_colon_sp, Some("="), Some(50));
+                            if let Ok(ref snippet) = sm.span_to_snippet(eq_span) && snippet == "=" {
+                                err.span_suggestion(
+                                    base_span,
+                                    "maybe you meant to write an assignment here",
+                                    format!("let {}", base_snippet),
+                                    Applicability::MaybeIncorrect,
+                                );
+                                show_label = false;
                             }
                         }
                     }
@@ -1815,6 +1780,31 @@ impl<'a: 'ast, 'ast> LateResolutionVisitor<'a, '_, 'ast> {
         false
     }
 
+    fn let_binding_suggestion(&self, err: &mut Diagnostic, ident_span: Span) -> bool {
+        // try to give a suggestion for this pattern: `name = 1`, which is common in other languages
+        let mut added_suggestion = false;
+        if let Some(Expr { kind: ExprKind::Assign(lhs, _rhs, _), .. }) = self.diagnostic_metadata.in_assignment &&
+            let ast::ExprKind::Path(None, _) = lhs.kind {
+                let sm = self.r.session.source_map();
+                let line_span = sm.span_extend_to_line(ident_span);
+                let ident_name = sm.span_to_snippet(ident_span).unwrap();
+                // HACK(chenyukang): make sure ident_name is at the starting of the line to protect against macros
+                if sm
+                    .span_to_snippet(line_span)
+                    .map_or(false, |s| s.trim().starts_with(&ident_name))
+                {
+                    err.span_suggestion_verbose(
+                        ident_span.shrink_to_lo(),
+                        "you might have meant to introduce a new binding",
+                        "let ".to_string(),
+                        Applicability::MaybeIncorrect,
+                    );
+                    added_suggestion = true;
+                }
+            }
+        added_suggestion
+    }
+
     fn find_module(&mut self, def_id: DefId) -> Option<(Module<'a>, ImportSuggestion)> {
         let mut result = None;
         let mut seen_modules = FxHashSet::default();
diff --git a/compiler/rustc_span/src/source_map.rs b/compiler/rustc_span/src/source_map.rs
index 506ce6955d399..f9566eeee9465 100644
--- a/compiler/rustc_span/src/source_map.rs
+++ b/compiler/rustc_span/src/source_map.rs
@@ -877,6 +877,26 @@ impl SourceMap {
         Span::new(BytePos(start_of_next_point), end_of_next_point, sp.ctxt(), None)
     }
 
+    /// Returns a new span to check next none-whitespace character or some specified expected character
+    /// If `expect` is none, the first span of non-whitespace character is returned.
+    /// If `expect` presented, the first span of the character `expect` is returned
+    /// Otherwise, the span reached to limit is returned.
+    pub fn span_look_ahead(&self, span: Span, expect: Option<&str>, limit: Option<usize>) -> Span {
+        let mut sp = span;
+        for _ in 0..limit.unwrap_or(100 as usize) {
+            sp = self.next_point(sp);
+            if let Ok(ref snippet) = self.span_to_snippet(sp) {
+                if expect.map_or(false, |es| snippet == es) {
+                    break;
+                }
+                if expect.is_none() && snippet.chars().any(|c| !c.is_whitespace()) {
+                    break;
+                }
+            }
+        }
+        sp
+    }
+
     /// Finds the width of the character, either before or after the end of provided span,
     /// depending on the `forwards` parameter.
     fn find_width_of_character_at_span(&self, sp: Span, forwards: bool) -> u32 {
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
index b7e6a564f3953..c850b30259ed3 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/mod.rs
@@ -764,6 +764,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                             self.suggest_borrowing_for_object_cast(&mut err, &root_obligation, *concrete_ty, *obj_ty);
                         }
 
+                        let mut unsatisfied_const = false;
                         if trait_predicate.is_const_if_const() && obligation.param_env.is_const() {
                             let non_const_predicate = trait_ref.without_const();
                             let non_const_obligation = Obligation {
@@ -773,6 +774,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                                 recursion_depth: obligation.recursion_depth,
                             };
                             if self.predicate_may_hold(&non_const_obligation) {
+                                unsatisfied_const = true;
                                 err.span_note(
                                     span,
                                     &format!(
@@ -924,7 +926,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                                 }
                             }
                         } else if !trait_ref.has_non_region_infer()
-                            && self.predicate_can_apply(obligation.param_env, trait_ref)
+                            && self.predicate_can_apply(obligation.param_env, trait_predicate)
                         {
                             // If a where-clause may be useful, remind the
                             // user that they can add it.
@@ -939,7 +941,7 @@ impl<'tcx> TypeErrCtxtExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
                                 None,
                                 obligation.cause.body_id,
                             );
-                        } else if !suggested {
+                        } else if !suggested && !unsatisfied_const {
                             // Can't show anything else useful, try to find similar impls.
                             let impl_candidates = self.find_similar_impl_candidates(trait_predicate);
                             if !self.report_similar_impl_candidates(
@@ -1433,7 +1435,7 @@ trait InferCtxtPrivExt<'tcx> {
     fn predicate_can_apply(
         &self,
         param_env: ty::ParamEnv<'tcx>,
-        pred: ty::PolyTraitRef<'tcx>,
+        pred: ty::PolyTraitPredicate<'tcx>,
     ) -> bool;
 
     fn note_obligation_cause(&self, err: &mut Diagnostic, obligation: &PredicateObligation<'tcx>);
@@ -2508,7 +2510,7 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
     fn predicate_can_apply(
         &self,
         param_env: ty::ParamEnv<'tcx>,
-        pred: ty::PolyTraitRef<'tcx>,
+        pred: ty::PolyTraitPredicate<'tcx>,
     ) -> bool {
         struct ParamToVarFolder<'a, 'tcx> {
             infcx: &'a InferCtxt<'tcx>,
@@ -2552,7 +2554,7 @@ impl<'tcx> InferCtxtPrivExt<'tcx> for TypeErrCtxt<'_, 'tcx> {
             let obligation = Obligation::new(
                 ObligationCause::dummy(),
                 param_env,
-                cleaned_pred.without_const().to_predicate(selcx.tcx()),
+                cleaned_pred.to_predicate(selcx.tcx()),
             );
 
             self.predicate_may_hold(&obligation)
diff --git a/compiler/rustc_trait_selection/src/traits/project.rs b/compiler/rustc_trait_selection/src/traits/project.rs
index 693c172893154..c8276854016f0 100644
--- a/compiler/rustc_trait_selection/src/traits/project.rs
+++ b/compiler/rustc_trait_selection/src/traits/project.rs
@@ -264,7 +264,7 @@ fn project_and_unify_type<'cx, 'tcx>(
     };
     debug!(?normalized, ?obligations, "project_and_unify_type result");
     let actual = obligation.predicate.term;
-    // For an example where this is neccessary see src/test/ui/impl-trait/nested-return-type2.rs
+    // For an example where this is necessary see src/test/ui/impl-trait/nested-return-type2.rs
     // This allows users to omit re-mentioning all bounds on an associated type and just use an
     // `impl Trait` for the assoc type to add more bounds.
     let InferOk { value: actual, obligations: new } =
diff --git a/library/alloc/src/vec/mod.rs b/library/alloc/src/vec/mod.rs
index b5b2eb0ece0ee..6a71f08330ca9 100644
--- a/library/alloc/src/vec/mod.rs
+++ b/library/alloc/src/vec/mod.rs
@@ -1999,9 +1999,7 @@ impl<T, A: Allocator> Vec<T, A> {
         unsafe {
             // set self.vec length's to start, to be safe in case Drain is leaked
             self.set_len(start);
-            // Use the borrow in the IterMut to indicate borrowing behavior of the
-            // whole Drain iterator (like &mut T).
-            let range_slice = slice::from_raw_parts_mut(self.as_mut_ptr().add(start), end - start);
+            let range_slice = slice::from_raw_parts(self.as_ptr().add(start), end - start);
             Drain {
                 tail_start: end,
                 tail_len: len - end,
diff --git a/library/test/src/term.rs b/library/test/src/term.rs
index b256ab7b8f828..a14b0d4f5a962 100644
--- a/library/test/src/term.rs
+++ b/library/test/src/term.rs
@@ -39,7 +39,7 @@ pub(crate) fn stdout() -> Option<Box<StdoutTerminal>> {
 pub(crate) fn stdout() -> Option<Box<StdoutTerminal>> {
     TerminfoTerminal::new(io::stdout())
         .map(|t| Box::new(t) as Box<StdoutTerminal>)
-        .or_else(|| WinConsole::new(io::stdout()).ok().map(|t| Box::new(t) as Box<StdoutTerminal>))
+        .or_else(|| Some(Box::new(WinConsole::new(io::stdout())) as Box<StdoutTerminal>))
 }
 
 /// Terminal color definitions
diff --git a/library/test/src/term/win.rs b/library/test/src/term/win.rs
index 4bdbd6ee75f52..55020141a827d 100644
--- a/library/test/src/term/win.rs
+++ b/library/test/src/term/win.rs
@@ -113,8 +113,7 @@ impl<T: Write + Send + 'static> WinConsole<T> {
         }
     }
 
-    /// Returns `None` whenever the terminal cannot be created for some reason.
-    pub(crate) fn new(out: T) -> io::Result<WinConsole<T>> {
+    pub(crate) fn new(out: T) -> WinConsole<T> {
         use std::mem::MaybeUninit;
 
         let fg;
@@ -132,13 +131,13 @@ impl<T: Write + Send + 'static> WinConsole<T> {
                 bg = color::BLACK;
             }
         }
-        Ok(WinConsole {
+        WinConsole {
             buf: out,
             def_foreground: fg,
             def_background: bg,
             foreground: fg,
             background: bg,
-        })
+        }
     }
 }
 
diff --git a/src/librustdoc/html/static/css/rustdoc.css b/src/librustdoc/html/static/css/rustdoc.css
index afe1ca5d7e520..9785e1f54c1a4 100644
--- a/src/librustdoc/html/static/css/rustdoc.css
+++ b/src/librustdoc/html/static/css/rustdoc.css
@@ -634,7 +634,6 @@ pre.example-line-numbers {
 .out-of-band {
 	flex-grow: 0;
 	font-size: 1.125rem;
-	font-weight: normal;
 }
 
 .docblock code, .docblock-short code,
@@ -1536,6 +1535,7 @@ details.dir-entry a {
 	https://developer.mozilla.org/en-US/docs/Web/CSS/contain */
 details.rustdoc-toggle {
 	contain: layout;
+	position: relative;
 }
 
 /* The hideme class is used on summary tags that contain a span with
@@ -1629,10 +1629,6 @@ details.rustdoc-toggle[open] > summary.hideme {
 	position: absolute;
 }
 
-details.rustdoc-toggle {
-	position: relative;
-}
-
 details.rustdoc-toggle[open] > summary.hideme > span {
 	display: none;
 }
@@ -1983,8 +1979,8 @@ in storage.js
 	}
 }
 
-.method-toggle summary,
-.implementors-toggle summary,
+.method-toggle > summary,
+.implementors-toggle > summary,
 .impl,
 #implementors-list > .docblock,
 .impl-items > section,
@@ -1993,10 +1989,7 @@ in storage.js
 	margin-bottom: 0.75em;
 }
 
-.method-toggle[open]:not(:last-child) {
-	margin-bottom: 2em;
-}
-
+.method-toggle[open]:not(:last-child),
 .implementors-toggle[open]:not(:last-child) {
 	margin-bottom: 2em;
 }
diff --git a/src/test/rustdoc-gui/docblock-details.goml b/src/test/rustdoc-gui/docblock-details.goml
index f3cbe5767ae91..9ae571efbb587 100644
--- a/src/test/rustdoc-gui/docblock-details.goml
+++ b/src/test/rustdoc-gui/docblock-details.goml
@@ -21,3 +21,14 @@ assert-property: (".top-doc .docblock summary h4", {"offsetHeight": "33"})
 assert-css: (".top-doc .docblock summary h4", {"margin-top": "15px", "margin-bottom": "5px"})
 // So `33 + 15 + 5` == `53`
 assert-property: (".top-doc .docblock summary", {"offsetHeight": "53"})
+
+// We now check the `<summary>` on a method.
+assert-css: (
+    ".method-toggle .docblock summary h4",
+    {"border-bottom-width": "0px"},
+)
+// This allows to ensure that summary is on one line only!
+assert-property: (".method-toggle .docblock summary h4", {"offsetHeight": "30"})
+assert-css: (".method-toggle .docblock summary h4", {"margin-top": "15px", "margin-bottom": "5px"})
+// So `30 + 15 + 5` == `50`
+assert-property: (".method-toggle .docblock summary", {"offsetHeight": "50"})
diff --git a/src/test/rustdoc-gui/src/test_docs/lib.rs b/src/test/rustdoc-gui/src/test_docs/lib.rs
index 77617e10beb70..fdf97e492aa2b 100644
--- a/src/test/rustdoc-gui/src/test_docs/lib.rs
+++ b/src/test/rustdoc-gui/src/test_docs/lib.rs
@@ -317,6 +317,18 @@ pub mod details {
     /// <div>I'm the content of the details!</div>
     /// </details>
     pub struct Details;
+
+    impl Details {
+        /// We check the appearance of the `<details>`/`<summary>` in here.
+        ///
+        /// ## Hello
+        ///
+        /// <details>
+        /// <summary><h4>I'm a summary</h4></summary>
+        /// <div>I'm the content of the details!</div>
+        /// </details>
+        pub fn method() {}
+    }
 }
 
 pub mod doc_block_table {
diff --git a/src/test/ui/closures/issue-97607.rs b/src/test/ui/closures/issue-97607.rs
new file mode 100644
index 0000000000000..74c910ad0bba6
--- /dev/null
+++ b/src/test/ui/closures/issue-97607.rs
@@ -0,0 +1,12 @@
+// check-pass
+#[allow(unused)]
+
+fn test<T, F, U>(f: F) -> Box<dyn Fn(T) -> U + 'static>
+where
+    F: 'static + Fn(T) -> U,
+    for<'a> U: 'a, // < This is the problematic line, see #97607
+{
+    Box::new(move |t| f(t))
+}
+
+fn main() {}
diff --git a/src/test/ui/consts/const-eval/const_raw_ptr_ops.stderr b/src/test/ui/consts/const-eval/const_raw_ptr_ops.stderr
index 168fa0ad0f0ed..12244450e7f8f 100644
--- a/src/test/ui/consts/const-eval/const_raw_ptr_ops.stderr
+++ b/src/test/ui/consts/const-eval/const_raw_ptr_ops.stderr
@@ -10,16 +10,6 @@ note: the trait `PartialEq<_>` is implemented for `*const i32`, but that impleme
    |
 LL | const X: bool = unsafe { &1 as *const i32 == &2 as *const i32 };
    |                                           ^^
-   = help: the following other types implement trait `PartialEq<Rhs>`:
-             f32
-             f64
-             i128
-             i16
-             i32
-             i64
-             i8
-             isize
-           and 6 others
 
 error[E0277]: can't compare `*const i32` with `_` in const contexts
   --> $DIR/const_raw_ptr_ops.rs:6:44
@@ -33,16 +23,6 @@ note: the trait `PartialEq<_>` is implemented for `*const i32`, but that impleme
    |
 LL | const X2: bool = unsafe { 42 as *const i32 == 43 as *const i32 };
    |                                            ^^
-   = help: the following other types implement trait `PartialEq<Rhs>`:
-             f32
-             f64
-             i128
-             i16
-             i32
-             i64
-             i8
-             isize
-           and 6 others
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/consts/issue-25826.stderr b/src/test/ui/consts/issue-25826.stderr
index b80befa26f6e0..905c5ee6eb4a0 100644
--- a/src/test/ui/consts/issue-25826.stderr
+++ b/src/test/ui/consts/issue-25826.stderr
@@ -10,10 +10,6 @@ note: the trait `PartialOrd` is implemented for `*const ()`, but that implementa
    |
 LL |     const A: bool = unsafe { id::<u8> as *const () < id::<u16> as *const () };
    |                                                    ^
-help: consider introducing a `where` clause, but there might be an alternative better way to express this requirement
-   |
-LL | fn main() where *const (): ~const PartialOrd {
-   |           ++++++++++++++++++++++++++++++++++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/consts/issue-94675.stderr b/src/test/ui/consts/issue-94675.stderr
index 7ae293ffbf85d..f4683f7f5361d 100644
--- a/src/test/ui/consts/issue-94675.stderr
+++ b/src/test/ui/consts/issue-94675.stderr
@@ -23,10 +23,6 @@ note: the trait `IndexMut<usize>` is implemented for `Vec<usize>`, but that impl
    |
 LL |         self.bar[0] = baz.len();
    |         ^^^^^^^^^^^
-help: consider introducing a `where` clause, but there might be an alternative better way to express this requirement
-   |
-LL | impl<'a> Foo<'a> where Vec<usize>: ~const IndexMut<usize> {
-   |                  ++++++++++++++++++++++++++++++++++++++++
 
 error: aborting due to 2 previous errors
 
diff --git a/src/test/ui/generic-associated-types/bugs/issue-89008.stderr b/src/test/ui/generic-associated-types/bugs/issue-89008.stderr
deleted file mode 100644
index 3f72734efa1dc..0000000000000
--- a/src/test/ui/generic-associated-types/bugs/issue-89008.stderr
+++ /dev/null
@@ -1,19 +0,0 @@
-error[E0271]: type mismatch resolving `<Empty<_> as Stream>::Item == Repr`
-  --> $DIR/issue-89008.rs:38:43
-   |
-LL |     fn line_stream<'a, Repr>(&'a self) -> Self::LineStreamFut<'a, Repr> {
-   |                        ----               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ type mismatch resolving `<Empty<_> as Stream>::Item == Repr`
-   |                        |
-   |                        this type parameter
-   |
-note: expected this to be `()`
-  --> $DIR/issue-89008.rs:17:17
-   |
-LL |     type Item = ();
-   |                 ^^
-   = note:   expected unit type `()`
-           found type parameter `Repr`
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0271`.
diff --git a/src/test/ui/generic-associated-types/bugs/issue-91762.rs b/src/test/ui/generic-associated-types/bugs/issue-91762.rs
index 796935cc06f5b..dec668bec10ed 100644
--- a/src/test/ui/generic-associated-types/bugs/issue-91762.rs
+++ b/src/test/ui/generic-associated-types/bugs/issue-91762.rs
@@ -1,7 +1,7 @@
 // check-fail
 // known-bug
 
-// We almost certaintly want this to pass, but
+// We almost certainly want this to pass, but
 // it's particularly difficult currently, because we need a way of specifying
 // that `<Self::Base as Functor>::With<T> = Self` without using that when we have
 // a `U`. See `https://github.com/rust-lang/rust/pull/92728` for a (hacky)
diff --git a/src/test/ui/generic-associated-types/bugs/issue-89008.rs b/src/test/ui/generic-associated-types/issue-89008.rs
similarity index 55%
rename from src/test/ui/generic-associated-types/bugs/issue-89008.rs
rename to src/test/ui/generic-associated-types/issue-89008.rs
index 012aa8df2fc3f..669dbafb5d5de 100644
--- a/src/test/ui/generic-associated-types/bugs/issue-89008.rs
+++ b/src/test/ui/generic-associated-types/issue-89008.rs
@@ -1,42 +1,36 @@
-// check-fail
+// check-pass
 // edition:2021
-// known-bug: #88908
-
-// This should pass, but seems to run into a TAIT bug.
 
 #![feature(type_alias_impl_trait)]
 
 use std::future::Future;
+use std::marker::PhantomData;
 
 trait Stream {
     type Item;
 }
 
-struct Empty<T>(T);
-impl<T> Stream for Empty<T> {
-    type Item = ();
+struct Empty<T> {
+    _phantom: PhantomData<T>,
 }
-fn empty<T>() -> Empty<T> {
-    todo!()
+
+impl<T> Stream for Empty<T> {
+    type Item = T;
 }
 
 trait X {
     type LineStream<'a, Repr>: Stream<Item = Repr> where Self: 'a;
-
-    type LineStreamFut<'a,Repr>: Future<Output = Self::LineStream<'a, Repr>> where Self: 'a;
-
-    fn line_stream<'a,Repr>(&'a self) -> Self::LineStreamFut<'a,Repr>;
+    type LineStreamFut<'a, Repr>: Future<Output = Self::LineStream<'a, Repr>> where Self: 'a;
+    fn line_stream<'a, Repr>(&'a self) -> Self::LineStreamFut<'a, Repr>;
 }
 
 struct Y;
 
 impl X for Y {
     type LineStream<'a, Repr> = impl Stream<Item = Repr>;
-
-    type LineStreamFut<'a, Repr> = impl Future<Output = Self::LineStream<'a, Repr>> ;
-
+    type LineStreamFut<'a, Repr> = impl Future<Output = Self::LineStream<'a, Repr>>;
     fn line_stream<'a, Repr>(&'a self) -> Self::LineStreamFut<'a, Repr> {
-        async {empty()}
+        async { Empty { _phantom: PhantomData } }
     }
 }
 
diff --git a/src/test/ui/let-else/let-else-non-diverging.rs b/src/test/ui/let-else/let-else-non-diverging.rs
index 58d2c09776f98..a5442dd82f028 100644
--- a/src/test/ui/let-else/let-else-non-diverging.rs
+++ b/src/test/ui/let-else/let-else-non-diverging.rs
@@ -11,7 +11,7 @@ fn main() {
 
     // Ensure that uninhabited types do not "diverge".
     // This might be relaxed in the future, but when it is,
-    // it should be an explicitly wanted descision.
+    // it should be an explicitly wanted decision.
     let Some(x) = Some(1) else { foo::<Uninhabited>() }; //~ ERROR does not diverge
 }
 
diff --git a/src/test/ui/lint/lint-incoherent-auto-trait-objects.stderr b/src/test/ui/lint/lint-incoherent-auto-trait-objects.stderr
index 3f366bedbf376..2cc4d382d9df9 100644
--- a/src/test/ui/lint/lint-incoherent-auto-trait-objects.stderr
+++ b/src/test/ui/lint/lint-incoherent-auto-trait-objects.stderr
@@ -37,3 +37,45 @@ LL | impl Foo for dyn Send + Sync + Send {}
 
 error: aborting due to 3 previous errors
 
+Future incompatibility report: Future breakage diagnostic:
+error: conflicting implementations of trait `Foo` for type `(dyn std::marker::Send + 'static)`: (E0119)
+  --> $DIR/lint-incoherent-auto-trait-objects.rs:5:1
+   |
+LL | impl Foo for dyn Send {}
+   | --------------------- first implementation here
+LL |
+LL | impl Foo for dyn Send + Send {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + 'static)`
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
+   = note: `#[deny(order_dependent_trait_objects)]` on by default
+
+Future breakage diagnostic:
+error: conflicting implementations of trait `Foo` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`: (E0119)
+  --> $DIR/lint-incoherent-auto-trait-objects.rs:11:1
+   |
+LL | impl Foo for dyn Send + Sync {}
+   | ---------------------------- first implementation here
+LL |
+LL | impl Foo for dyn Sync + Send {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
+   = note: `#[deny(order_dependent_trait_objects)]` on by default
+
+Future breakage diagnostic:
+error: conflicting implementations of trait `Foo` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`: (E0119)
+  --> $DIR/lint-incoherent-auto-trait-objects.rs:15:1
+   |
+LL | impl Foo for dyn Sync + Send {}
+   | ---------------------------- first implementation here
+...
+LL | impl Foo for dyn Send + Sync + Send {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
+   = note: `#[deny(order_dependent_trait_objects)]` on by default
+
diff --git a/src/test/ui/rfc-2632-const-trait-impl/assoc-type.stderr b/src/test/ui/rfc-2632-const-trait-impl/assoc-type.stderr
index ce2425010ad28..89177b0f1ac1c 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/assoc-type.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/assoc-type.stderr
@@ -15,10 +15,6 @@ note: required by a bound in `Foo::Bar`
    |
 LL |     type Bar: ~const std::ops::Add;
    |               ^^^^^^^^^^^^^^^^^^^^ required by this bound in `Foo::Bar`
-help: consider introducing a `where` clause, but there might be an alternative better way to express this requirement
-   |
-LL | impl const Foo for NonConstAdd where NonConstAdd: ~const Add {
-   |                                +++++++++++++++++++++++++++++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/rfc-2632-const-trait-impl/call-const-trait-method-fail.stderr b/src/test/ui/rfc-2632-const-trait-impl/call-const-trait-method-fail.stderr
index d9ad80431533b..7350909ba8e19 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/call-const-trait-method-fail.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/call-const-trait-method-fail.stderr
@@ -9,10 +9,6 @@ note: the trait `Plus` is implemented for `u32`, but that implementation is not
    |
 LL |     a.plus(b)
    |       ^^^^
-help: consider introducing a `where` clause, but there might be an alternative better way to express this requirement
-   |
-LL | pub const fn add_u32(a: u32, b: u32) -> u32 where u32: ~const Plus {
-   |                                             ++++++++++++++++++++++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/rfc-2632-const-trait-impl/call-generic-method-fail.stderr b/src/test/ui/rfc-2632-const-trait-impl/call-generic-method-fail.stderr
index 83d395dda196a..31e6dbdab2258 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/call-generic-method-fail.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/call-generic-method-fail.stderr
@@ -9,7 +9,6 @@ note: the trait `PartialEq<_>` is implemented for `T`, but that implementation i
    |
 LL |     *t == *t
    |        ^^
-   = help: the trait `PartialEq<&B>` is implemented for `&A`
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/rfc-2632-const-trait-impl/const-default-method-bodies.stderr b/src/test/ui/rfc-2632-const-trait-impl/const-default-method-bodies.stderr
index fddc8d37f2ff7..c64930db9bee2 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/const-default-method-bodies.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/const-default-method-bodies.stderr
@@ -11,10 +11,6 @@ note: the trait `ConstDefaultFn` is implemented for `NonConstImpl`, but that imp
    |
 LL |     NonConstImpl.a();
    |     ^^^^^^^^^^^^
-help: consider introducing a `where` clause, but there might be an alternative better way to express this requirement
-   |
-LL | const fn test() where NonConstImpl: ~const ConstDefaultFn {
-   |                 +++++++++++++++++++++++++++++++++++++++++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.precise.stderr b/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.precise.stderr
index ddf0e2d91c097..796c0d388eaf0 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.precise.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.precise.stderr
@@ -45,34 +45,55 @@ note: required by a bound in `check`
 LL | const fn check<T: ~const Destruct>(_: T) {}
    |                   ^^^^^^^^^^^^^^^ required by this bound in `check`
 
-error[E0277]: the trait bound `ConstDropImplWithBounds<NonTrivialDrop>: ~const Destruct` is not satisfied
+error[E0277]: the trait bound `NonTrivialDrop: ~const A` is not satisfied
+  --> $DIR/const-drop-fail.rs:48:47
+   |
+LL |     ConstDropImplWithBounds::<NonTrivialDrop>(PhantomData),
+   |     ----------------------------------------- ^^^^^^^^^^^ the trait `~const A` is not implemented for `NonTrivialDrop`
+   |     |
+   |     required by a bound introduced by this call
+   |
+note: the trait `A` is implemented for `NonTrivialDrop`, but that implementation is not `const`
+  --> $DIR/const-drop-fail.rs:48:47
+   |
+LL |     ConstDropImplWithBounds::<NonTrivialDrop>(PhantomData),
+   |                                               ^^^^^^^^^^^
+note: required by a bound in `ConstDropImplWithBounds`
+  --> $DIR/const-drop-fail.rs:27:35
+   |
+LL | struct ConstDropImplWithBounds<T: ~const A>(PhantomData<T>);
+   |                                   ^^^^^^^^ required by this bound in `ConstDropImplWithBounds`
+
+error[E0277]: the trait bound `NonTrivialDrop: ~const A` is not satisfied
+  --> $DIR/const-drop-fail.rs:48:5
+   |
+LL |     ConstDropImplWithBounds::<NonTrivialDrop>(PhantomData),
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `~const A` is not implemented for `NonTrivialDrop`
+   |
+note: the trait `A` is implemented for `NonTrivialDrop`, but that implementation is not `const`
   --> $DIR/const-drop-fail.rs:48:5
    |
-LL |         const _: () = check($exp);
-   |                       ----- required by a bound introduced by this call
-...
 LL |     ConstDropImplWithBounds::<NonTrivialDrop>(PhantomData),
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `~const Destruct` is not implemented for `ConstDropImplWithBounds<NonTrivialDrop>`
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+note: required by a bound in `ConstDropImplWithBounds`
+  --> $DIR/const-drop-fail.rs:27:35
    |
-note: required for `ConstDropImplWithBounds<NonTrivialDrop>` to implement `~const Destruct`
-  --> $DIR/const-drop-fail.rs:29:25
+LL | struct ConstDropImplWithBounds<T: ~const A>(PhantomData<T>);
+   |                                   ^^^^^^^^ required by this bound in `ConstDropImplWithBounds`
+
+error[E0367]: `Drop` impl requires `T: ~const A` but the struct it is implemented for does not
+  --> $DIR/const-drop-fail.rs:55:9
    |
-LL | impl<T: ~const A> const Drop for ConstDropImplWithBounds<T> {
-   |                         ^^^^     ^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: 1 redundant requirement hidden
-   = note: required for `ConstDropImplWithBounds<NonTrivialDrop>` to implement `~const Destruct`
-note: required by a bound in `check`
-  --> $DIR/const-drop-fail.rs:35:19
+LL | impl<T: ~const A> const Drop for ConstDropImplWithNonConstBounds<T> {
+   |         ^^^^^^^^
    |
-LL | const fn check<T: ~const Destruct>(_: T) {}
-   |                   ^^^^^^^^^^^^^^^ required by this bound in `check`
-help: consider borrowing here
+note: the implementor must specify the same requirement
+  --> $DIR/const-drop-fail.rs:53:1
    |
-LL |     &ConstDropImplWithBounds::<NonTrivialDrop>(PhantomData),
-   |     +
-LL |     &mut ConstDropImplWithBounds::<NonTrivialDrop>(PhantomData),
-   |     ++++
+LL | struct ConstDropImplWithNonConstBounds<T: A>(PhantomData<T>);
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: aborting due to 3 previous errors
+error: aborting due to 5 previous errors
 
-For more information about this error, try `rustc --explain E0277`.
+Some errors have detailed explanations: E0277, E0367.
+For more information about an error, try `rustc --explain E0277`.
diff --git a/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.rs b/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.rs
index 565e2c77ac5ca..d36c7f81ced8c 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.rs
+++ b/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.rs
@@ -24,7 +24,7 @@ trait A { fn a() { } }
 
 impl A for NonTrivialDrop {}
 
-struct ConstDropImplWithBounds<T: A>(PhantomData<T>);
+struct ConstDropImplWithBounds<T: ~const A>(PhantomData<T>);
 
 impl<T: ~const A> const Drop for ConstDropImplWithBounds<T> {
     fn drop(&mut self) {
@@ -47,6 +47,16 @@ check_all! {
     //~^ ERROR can't drop
     ConstDropImplWithBounds::<NonTrivialDrop>(PhantomData),
     //~^ ERROR the trait bound
+    //~| ERROR the trait bound
+}
+
+struct ConstDropImplWithNonConstBounds<T: A>(PhantomData<T>);
+
+impl<T: ~const A> const Drop for ConstDropImplWithNonConstBounds<T> {
+//~^ ERROR `Drop` impl requires `T: ~const A` but the struct it is implemented for does not
+    fn drop(&mut self) {
+        T::a();
+    }
 }
 
 fn main() {}
diff --git a/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.stock.stderr b/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.stock.stderr
index ddf0e2d91c097..796c0d388eaf0 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.stock.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/const-drop-fail.stock.stderr
@@ -45,34 +45,55 @@ note: required by a bound in `check`
 LL | const fn check<T: ~const Destruct>(_: T) {}
    |                   ^^^^^^^^^^^^^^^ required by this bound in `check`
 
-error[E0277]: the trait bound `ConstDropImplWithBounds<NonTrivialDrop>: ~const Destruct` is not satisfied
+error[E0277]: the trait bound `NonTrivialDrop: ~const A` is not satisfied
+  --> $DIR/const-drop-fail.rs:48:47
+   |
+LL |     ConstDropImplWithBounds::<NonTrivialDrop>(PhantomData),
+   |     ----------------------------------------- ^^^^^^^^^^^ the trait `~const A` is not implemented for `NonTrivialDrop`
+   |     |
+   |     required by a bound introduced by this call
+   |
+note: the trait `A` is implemented for `NonTrivialDrop`, but that implementation is not `const`
+  --> $DIR/const-drop-fail.rs:48:47
+   |
+LL |     ConstDropImplWithBounds::<NonTrivialDrop>(PhantomData),
+   |                                               ^^^^^^^^^^^
+note: required by a bound in `ConstDropImplWithBounds`
+  --> $DIR/const-drop-fail.rs:27:35
+   |
+LL | struct ConstDropImplWithBounds<T: ~const A>(PhantomData<T>);
+   |                                   ^^^^^^^^ required by this bound in `ConstDropImplWithBounds`
+
+error[E0277]: the trait bound `NonTrivialDrop: ~const A` is not satisfied
+  --> $DIR/const-drop-fail.rs:48:5
+   |
+LL |     ConstDropImplWithBounds::<NonTrivialDrop>(PhantomData),
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `~const A` is not implemented for `NonTrivialDrop`
+   |
+note: the trait `A` is implemented for `NonTrivialDrop`, but that implementation is not `const`
   --> $DIR/const-drop-fail.rs:48:5
    |
-LL |         const _: () = check($exp);
-   |                       ----- required by a bound introduced by this call
-...
 LL |     ConstDropImplWithBounds::<NonTrivialDrop>(PhantomData),
-   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the trait `~const Destruct` is not implemented for `ConstDropImplWithBounds<NonTrivialDrop>`
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+note: required by a bound in `ConstDropImplWithBounds`
+  --> $DIR/const-drop-fail.rs:27:35
    |
-note: required for `ConstDropImplWithBounds<NonTrivialDrop>` to implement `~const Destruct`
-  --> $DIR/const-drop-fail.rs:29:25
+LL | struct ConstDropImplWithBounds<T: ~const A>(PhantomData<T>);
+   |                                   ^^^^^^^^ required by this bound in `ConstDropImplWithBounds`
+
+error[E0367]: `Drop` impl requires `T: ~const A` but the struct it is implemented for does not
+  --> $DIR/const-drop-fail.rs:55:9
    |
-LL | impl<T: ~const A> const Drop for ConstDropImplWithBounds<T> {
-   |                         ^^^^     ^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: 1 redundant requirement hidden
-   = note: required for `ConstDropImplWithBounds<NonTrivialDrop>` to implement `~const Destruct`
-note: required by a bound in `check`
-  --> $DIR/const-drop-fail.rs:35:19
+LL | impl<T: ~const A> const Drop for ConstDropImplWithNonConstBounds<T> {
+   |         ^^^^^^^^
    |
-LL | const fn check<T: ~const Destruct>(_: T) {}
-   |                   ^^^^^^^^^^^^^^^ required by this bound in `check`
-help: consider borrowing here
+note: the implementor must specify the same requirement
+  --> $DIR/const-drop-fail.rs:53:1
    |
-LL |     &ConstDropImplWithBounds::<NonTrivialDrop>(PhantomData),
-   |     +
-LL |     &mut ConstDropImplWithBounds::<NonTrivialDrop>(PhantomData),
-   |     ++++
+LL | struct ConstDropImplWithNonConstBounds<T: A>(PhantomData<T>);
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-error: aborting due to 3 previous errors
+error: aborting due to 5 previous errors
 
-For more information about this error, try `rustc --explain E0277`.
+Some errors have detailed explanations: E0277, E0367.
+For more information about an error, try `rustc --explain E0277`.
diff --git a/src/test/ui/rfc-2632-const-trait-impl/const-drop.rs b/src/test/ui/rfc-2632-const-trait-impl/const-drop.rs
index 8b4c406581565..b0fc3adf984a4 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/const-drop.rs
+++ b/src/test/ui/rfc-2632-const-trait-impl/const-drop.rs
@@ -60,7 +60,7 @@ mod t {
         fn foo() {}
     }
 
-    pub struct ConstDropWithBound<T: SomeTrait>(pub core::marker::PhantomData<T>);
+    pub struct ConstDropWithBound<T: ~const SomeTrait>(pub core::marker::PhantomData<T>);
 
     impl<T: ~const SomeTrait> const Drop for ConstDropWithBound<T> {
         fn drop(&mut self) {
diff --git a/src/test/ui/rfc-2632-const-trait-impl/cross-crate.gatednc.stderr b/src/test/ui/rfc-2632-const-trait-impl/cross-crate.gatednc.stderr
index d4fa44b4bfcb5..925ae53e32499 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/cross-crate.gatednc.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/cross-crate.gatednc.stderr
@@ -11,10 +11,6 @@ note: the trait `cross_crate::MyTrait` is implemented for `cross_crate::NonConst
    |
 LL |     NonConst.func();
    |     ^^^^^^^^
-help: consider introducing a `where` clause, but there might be an alternative better way to express this requirement
-   |
-LL | const fn const_context() where cross_crate::NonConst: ~const cross_crate::MyTrait {
-   |                          ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/rfc-2632-const-trait-impl/cross-crate.stocknc.stderr b/src/test/ui/rfc-2632-const-trait-impl/cross-crate.stocknc.stderr
index 71ecd9b06945f..11db0c2b8f290 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/cross-crate.stocknc.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/cross-crate.stocknc.stderr
@@ -11,10 +11,6 @@ note: the trait `cross_crate::MyTrait` is implemented for `cross_crate::NonConst
    |
 LL |     NonConst.func();
    |     ^^^^^^^^
-help: consider introducing a `where` clause, but there might be an alternative better way to express this requirement
-   |
-LL | const fn const_context() where cross_crate::NonConst: ~const cross_crate::MyTrait {
-   |                          ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/rfc-2632-const-trait-impl/default-method-body-is-const-body-checking.stderr b/src/test/ui/rfc-2632-const-trait-impl/default-method-body-is-const-body-checking.stderr
index d102956cd2ec2..a244ab10cab6b 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/default-method-body-is-const-body-checking.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/default-method-body-is-const-body-checking.stderr
@@ -14,10 +14,6 @@ note: required by a bound in `foo`
    |
 LL | const fn foo<T>() where T: ~const Tr {}
    |                            ^^^^^^^^^ required by this bound in `foo`
-help: consider introducing a `where` clause, but there might be an alternative better way to express this requirement
-   |
-LL | pub trait Foo where (): ~const Tr {
-   |               +++++++++++++++++++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/rfc-2632-const-trait-impl/default-method-body-is-const-same-trait-ck.stderr b/src/test/ui/rfc-2632-const-trait-impl/default-method-body-is-const-same-trait-ck.stderr
index 85285ba849777..c2c16921c2eb2 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/default-method-body-is-const-same-trait-ck.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/default-method-body-is-const-same-trait-ck.stderr
@@ -11,10 +11,6 @@ note: the trait `Tr` is implemented for `()`, but that implementation is not `co
    |
 LL |         ().a()
    |         ^^
-help: consider introducing a `where` clause, but there might be an alternative better way to express this requirement
-   |
-LL | pub trait Tr where (): ~const Tr {
-   |              +++++++++++++++++++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail.stderr b/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail.stderr
index 9787792ab1318..1f8f312df0128 100644
--- a/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail.stderr
+++ b/src/test/ui/rfc-2632-const-trait-impl/super-traits-fail.stderr
@@ -14,10 +14,6 @@ note: required by a bound in `Bar`
    |
 LL | trait Bar: ~const Foo {}
    |            ^^^^^^^^^^ required by this bound in `Bar`
-help: consider introducing a `where` clause, but there might be an alternative better way to express this requirement
-   |
-LL | impl const Bar for S where S: ~const Foo {}
-   |                      +++++++++++++++++++
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/rfc-2632-const-trait-impl/tilde_const_on_impl_bound.rs b/src/test/ui/rfc-2632-const-trait-impl/tilde_const_on_impl_bound.rs
new file mode 100644
index 0000000000000..285cef571f332
--- /dev/null
+++ b/src/test/ui/rfc-2632-const-trait-impl/tilde_const_on_impl_bound.rs
@@ -0,0 +1,17 @@
+// check-pass
+#![feature(const_trait_impl)]
+
+#[const_trait]
+trait Foo {
+    fn foo(&self) {}
+}
+
+struct Bar<T>(T);
+
+impl<T: ~const Foo> Bar<T> {
+    const fn foo(&self) {
+        self.0.foo()
+    }
+}
+
+fn main() {}
diff --git a/src/test/ui/suggestions/suggest-let-for-assignment.fixed b/src/test/ui/suggestions/suggest-let-for-assignment.fixed
new file mode 100644
index 0000000000000..3a25e25eede62
--- /dev/null
+++ b/src/test/ui/suggestions/suggest-let-for-assignment.fixed
@@ -0,0 +1,17 @@
+// run-rustfix
+
+fn main() {
+    let demo = 1; //~ ERROR cannot find value `demo` in this scope
+    dbg!(demo); //~ ERROR cannot find value `demo` in this scope
+
+    let x = "x"; //~ ERROR cannot find value `x` in this scope
+    println!("x: {}", x); //~ ERROR cannot find value `x` in this scope
+
+    if x == "x" {
+        //~^ ERROR cannot find value `x` in this scope
+        println!("x is 1");
+    }
+
+    let y = 1 + 2; //~ ERROR cannot find value `y` in this scope
+    println!("y: {}", y); //~ ERROR cannot find value `y` in this scope
+}
diff --git a/src/test/ui/suggestions/suggest-let-for-assignment.rs b/src/test/ui/suggestions/suggest-let-for-assignment.rs
new file mode 100644
index 0000000000000..67705fe063a79
--- /dev/null
+++ b/src/test/ui/suggestions/suggest-let-for-assignment.rs
@@ -0,0 +1,17 @@
+// run-rustfix
+
+fn main() {
+    demo = 1; //~ ERROR cannot find value `demo` in this scope
+    dbg!(demo); //~ ERROR cannot find value `demo` in this scope
+
+    x = "x"; //~ ERROR cannot find value `x` in this scope
+    println!("x: {}", x); //~ ERROR cannot find value `x` in this scope
+
+    if x == "x" {
+        //~^ ERROR cannot find value `x` in this scope
+        println!("x is 1");
+    }
+
+    y = 1 + 2; //~ ERROR cannot find value `y` in this scope
+    println!("y: {}", y); //~ ERROR cannot find value `y` in this scope
+}
diff --git a/src/test/ui/suggestions/suggest-let-for-assignment.stderr b/src/test/ui/suggestions/suggest-let-for-assignment.stderr
new file mode 100644
index 0000000000000..3f6a3da4be2b3
--- /dev/null
+++ b/src/test/ui/suggestions/suggest-let-for-assignment.stderr
@@ -0,0 +1,60 @@
+error[E0425]: cannot find value `demo` in this scope
+  --> $DIR/suggest-let-for-assignment.rs:4:5
+   |
+LL |     demo = 1;
+   |     ^^^^
+   |
+help: you might have meant to introduce a new binding
+   |
+LL |     let demo = 1;
+   |     +++
+
+error[E0425]: cannot find value `demo` in this scope
+  --> $DIR/suggest-let-for-assignment.rs:5:10
+   |
+LL |     dbg!(demo);
+   |          ^^^^ not found in this scope
+
+error[E0425]: cannot find value `x` in this scope
+  --> $DIR/suggest-let-for-assignment.rs:7:5
+   |
+LL |     x = "x";
+   |     ^
+   |
+help: you might have meant to introduce a new binding
+   |
+LL |     let x = "x";
+   |     +++
+
+error[E0425]: cannot find value `x` in this scope
+  --> $DIR/suggest-let-for-assignment.rs:8:23
+   |
+LL |     println!("x: {}", x);
+   |                       ^ not found in this scope
+
+error[E0425]: cannot find value `x` in this scope
+  --> $DIR/suggest-let-for-assignment.rs:10:8
+   |
+LL |     if x == "x" {
+   |        ^ not found in this scope
+
+error[E0425]: cannot find value `y` in this scope
+  --> $DIR/suggest-let-for-assignment.rs:15:5
+   |
+LL |     y = 1 + 2;
+   |     ^
+   |
+help: you might have meant to introduce a new binding
+   |
+LL |     let y = 1 + 2;
+   |     +++
+
+error[E0425]: cannot find value `y` in this scope
+  --> $DIR/suggest-let-for-assignment.rs:16:23
+   |
+LL |     println!("y: {}", y);
+   |                       ^ not found in this scope
+
+error: aborting due to 7 previous errors
+
+For more information about this error, try `rustc --explain E0425`.
diff --git a/src/test/ui/traits/issue-33140-hack-boundaries.stderr b/src/test/ui/traits/issue-33140-hack-boundaries.stderr
index 62cfca545b261..58286648d4feb 100644
--- a/src/test/ui/traits/issue-33140-hack-boundaries.stderr
+++ b/src/test/ui/traits/issue-33140-hack-boundaries.stderr
@@ -66,3 +66,20 @@ error: aborting due to 8 previous errors
 
 Some errors have detailed explanations: E0119, E0751.
 For more information about an error, try `rustc --explain E0119`.
+Future incompatibility report: Future breakage diagnostic:
+warning: conflicting implementations of trait `Trait0` for type `(dyn std::marker::Send + 'static)`: (E0119)
+  --> $DIR/issue-33140-hack-boundaries.rs:10:1
+   |
+LL | impl Trait0 for dyn Send {}
+   | ------------------------ first implementation here
+LL | impl Trait0 for dyn Send {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + 'static)`
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
+note: the lint level is defined here
+  --> $DIR/issue-33140-hack-boundaries.rs:2:10
+   |
+LL | #![allow(order_dependent_trait_objects)]
+   |          ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
diff --git a/src/test/ui/traits/object/issue-33140-traitobject-crate.stderr b/src/test/ui/traits/object/issue-33140-traitobject-crate.stderr
index 4ab777bd4dfae..0af4df2aecb28 100644
--- a/src/test/ui/traits/object/issue-33140-traitobject-crate.stderr
+++ b/src/test/ui/traits/object/issue-33140-traitobject-crate.stderr
@@ -40,3 +40,56 @@ LL | unsafe impl Trait for dyn (::std::marker::Sync) + Send + Sync { }
 
 warning: 3 warnings emitted
 
+Future incompatibility report: Future breakage diagnostic:
+warning: conflicting implementations of trait `Trait` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`: (E0119)
+  --> $DIR/issue-33140-traitobject-crate.rs:86:1
+   |
+LL | unsafe impl Trait for dyn (::std::marker::Send) + Sync { }
+   | ------------------------------------------------------ first implementation here
+LL | unsafe impl Trait for dyn (::std::marker::Send) + Send + Sync { }
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
+note: the lint level is defined here
+  --> $DIR/issue-33140-traitobject-crate.rs:3:9
+   |
+LL | #![warn(order_dependent_trait_objects)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Future breakage diagnostic:
+warning: conflicting implementations of trait `Trait` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`: (E0119)
+  --> $DIR/issue-33140-traitobject-crate.rs:89:1
+   |
+LL | unsafe impl Trait for dyn (::std::marker::Send) + Send + Sync { }
+   | ------------------------------------------------------------- first implementation here
+...
+LL | unsafe impl Trait for dyn (::std::marker::Sync) + Send { }
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
+note: the lint level is defined here
+  --> $DIR/issue-33140-traitobject-crate.rs:3:9
+   |
+LL | #![warn(order_dependent_trait_objects)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Future breakage diagnostic:
+warning: conflicting implementations of trait `Trait` for type `(dyn std::marker::Send + std::marker::Sync + 'static)`: (E0119)
+  --> $DIR/issue-33140-traitobject-crate.rs:93:1
+   |
+LL | unsafe impl Trait for dyn (::std::marker::Sync) + Send { }
+   | ------------------------------------------------------ first implementation here
+...
+LL | unsafe impl Trait for dyn (::std::marker::Sync) + Send + Sync { }
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `(dyn std::marker::Send + std::marker::Sync + 'static)`
+   |
+   = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
+   = note: for more information, see issue #56484 <https://github.com/rust-lang/rust/issues/56484>
+note: the lint level is defined here
+  --> $DIR/issue-33140-traitobject-crate.rs:3:9
+   |
+LL | #![warn(order_dependent_trait_objects)]
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
diff --git a/src/test/ui/traits/trait-upcasting/multiple-occurence-ambiguousity.rs b/src/test/ui/traits/trait-upcasting/multiple-occurrence-ambiguousity.rs
similarity index 100%
rename from src/test/ui/traits/trait-upcasting/multiple-occurence-ambiguousity.rs
rename to src/test/ui/traits/trait-upcasting/multiple-occurrence-ambiguousity.rs
diff --git a/src/test/ui/traits/trait-upcasting/multiple-occurence-ambiguousity.stderr b/src/test/ui/traits/trait-upcasting/multiple-occurrence-ambiguousity.stderr
similarity index 88%
rename from src/test/ui/traits/trait-upcasting/multiple-occurence-ambiguousity.stderr
rename to src/test/ui/traits/trait-upcasting/multiple-occurrence-ambiguousity.stderr
index e9670ad7def4d..9564813512c4a 100644
--- a/src/test/ui/traits/trait-upcasting/multiple-occurence-ambiguousity.stderr
+++ b/src/test/ui/traits/trait-upcasting/multiple-occurrence-ambiguousity.stderr
@@ -1,5 +1,5 @@
 error[E0308]: mismatched types
-  --> $DIR/multiple-occurence-ambiguousity.rs:21:26
+  --> $DIR/multiple-occurrence-ambiguousity.rs:21:26
    |
 LL |     let t: &dyn Bar<_> = s;
    |            -----------   ^ expected trait `Bar`, found trait `Foo`