Auto merge of #126996 - oli-obk:do_not_count_errors, r=nnethercote

Automatically taint InferCtxt when errors are emitted

r? `@nnethercote`

Basically `InferCtxt::dcx` now returns a `DiagCtxt` that refers back to the `Cell<Option<ErrorGuaranteed>>` of the `InferCtxt` and thus when invoking `Diag::emit`, and the diagnostic is an error, we taint the `InferCtxt` directly.

That change on its own has no effect at all, because `InferCtxt` already tracks whether errors have been emitted by recording the global error count when it gets opened, and checking at the end whether the count changed. So I removed that error count check, which had a bit of fallout that I immediately fixed by invoking `InferCtxt::dcx` instead of `TyCtxt::dcx` in a bunch of places.

The remaining new errors are because an error was reported in another query, and never bubbled up. I think they are minor enough for this to be ok, and sometimes it actually improves diagnostics, by not silencing useful diagnostics anymore.

fixes #126485 (cc `@olafes)`

There are more improvements we can do (like tainting in hir ty lowering), but I would rather do that in follow up PRs, because it requires some refactorings.

77 files changed, 886 insertions, 816 deletions

diff --git a/compiler/rustc_borrowck/src/borrowck_errors.rs b/compiler/rustc_borrowck/src/borrowck_errors.rs
index f26f8711dd4..8eb44458137 100644
--- a/compiler/rustc_borrowck/src/borrowck_errors.rs
+++ b/compiler/rustc_borrowck/src/borrowck_errors.rs
@@ -6,8 +6,8 @@ use rustc_middle::span_bug;
 use rustc_middle::ty::{self, Ty, TyCtxt};
 use rustc_span::Span;
 
-impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
-    pub fn dcx(&self) -> DiagCtxtHandle<'tcx> {
+impl<'infcx, 'tcx> crate::MirBorrowckCtxt<'_, '_, 'infcx, 'tcx> {
+    pub fn dcx(&self) -> DiagCtxtHandle<'infcx> {
         self.infcx.dcx()
     }
 
@@ -18,7 +18,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         place: &str,
         borrow_place: &str,
         value_place: &str,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         self.dcx().create_err(crate::session_diagnostics::MoveBorrow {
             place,
             span,
@@ -34,7 +34,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         desc: &str,
         borrow_span: Span,
         borrow_desc: &str,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         struct_span_code_err!(
             self.dcx(),
             span,
@@ -54,7 +54,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         old_loan_span: Span,
         old_opt_via: &str,
         old_load_end_span: Option<Span>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         let via = |msg: &str| if msg.is_empty() { "".to_string() } else { format!(" (via {msg})") };
         let mut err = struct_span_code_err!(
             self.dcx(),
@@ -101,7 +101,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         desc: &str,
         old_loan_span: Span,
         old_load_end_span: Option<Span>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         let mut err = struct_span_code_err!(
             self.dcx(),
             new_loan_span,
@@ -134,7 +134,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         noun_old: &str,
         old_opt_via: &str,
         previous_end_span: Option<Span>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         let mut err = struct_span_code_err!(
             self.dcx(),
             new_loan_span,
@@ -166,7 +166,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         old_opt_via: &str,
         previous_end_span: Option<Span>,
         second_borrow_desc: &str,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         let mut err = struct_span_code_err!(
             self.dcx(),
             new_loan_span,
@@ -198,7 +198,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         kind_old: &str,
         msg_old: &str,
         old_load_end_span: Option<Span>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         let via = |msg: &str| if msg.is_empty() { "".to_string() } else { format!(" (via {msg})") };
         let mut err = struct_span_code_err!(
             self.dcx(),
@@ -239,7 +239,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         span: Span,
         borrow_span: Span,
         desc: &str,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         struct_span_code_err!(
             self.dcx(),
             span,
@@ -256,12 +256,12 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         span: Span,
         desc: &str,
         is_arg: bool,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         let msg = if is_arg { "to immutable argument" } else { "twice to immutable variable" };
         struct_span_code_err!(self.dcx(), span, E0384, "cannot assign {} {}", msg, desc)
     }
 
-    pub(crate) fn cannot_assign(&self, span: Span, desc: &str) -> Diag<'tcx> {
+    pub(crate) fn cannot_assign(&self, span: Span, desc: &str) -> Diag<'infcx> {
         struct_span_code_err!(self.dcx(), span, E0594, "cannot assign to {}", desc)
     }
 
@@ -269,7 +269,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         &self,
         move_from_span: Span,
         move_from_desc: &str,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         struct_span_code_err!(
             self.dcx(),
             move_from_span,
@@ -287,7 +287,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         move_from_span: Span,
         ty: Ty<'_>,
         is_index: Option<bool>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         let type_name = match (&ty.kind(), is_index) {
             (&ty::Array(_, _), Some(true)) | (&ty::Array(_, _), None) => "array",
             (&ty::Slice(_), _) => "slice",
@@ -308,7 +308,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         &self,
         move_from_span: Span,
         container_ty: Ty<'_>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         struct_span_code_err!(
             self.dcx(),
             move_from_span,
@@ -325,7 +325,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         verb: &str,
         optional_adverb_for_moved: &str,
         moved_path: Option<String>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         let moved_path = moved_path.map(|mp| format!(": `{mp}`")).unwrap_or_default();
 
         struct_span_code_err!(
@@ -344,7 +344,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         span: Span,
         path: &str,
         reason: &str,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         struct_span_code_err!(
             self.dcx(),
             span,
@@ -362,7 +362,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         immutable_place: &str,
         immutable_section: &str,
         action: &str,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         struct_span_code_err!(
             self.dcx(),
             mutate_span,
@@ -380,7 +380,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         &self,
         span: Span,
         yield_span: Span,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         let coroutine_kind = self.body.coroutine.as_ref().unwrap().coroutine_kind;
         struct_span_code_err!(
             self.dcx(),
@@ -391,7 +391,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         .with_span_label(yield_span, "possible yield occurs here")
     }
 
-    pub(crate) fn cannot_borrow_across_destructor(&self, borrow_span: Span) -> Diag<'tcx> {
+    pub(crate) fn cannot_borrow_across_destructor(&self, borrow_span: Span) -> Diag<'infcx> {
         struct_span_code_err!(
             self.dcx(),
             borrow_span,
@@ -400,7 +400,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         )
     }
 
-    pub(crate) fn path_does_not_live_long_enough(&self, span: Span, path: &str) -> Diag<'tcx> {
+    pub(crate) fn path_does_not_live_long_enough(&self, span: Span, path: &str) -> Diag<'infcx> {
         struct_span_code_err!(self.dcx(), span, E0597, "{} does not live long enough", path,)
     }
 
@@ -410,7 +410,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         return_kind: &str,
         reference_desc: &str,
         path_desc: &str,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         struct_span_code_err!(
             self.dcx(),
             span,
@@ -433,7 +433,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         borrowed_path: &str,
         capture_span: Span,
         scope: &str,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         struct_span_code_err!(
             self.dcx(),
             closure_span,
@@ -445,7 +445,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         .with_span_label(closure_span, format!("may outlive borrowed value {borrowed_path}"))
     }
 
-    pub(crate) fn thread_local_value_does_not_live_long_enough(&self, span: Span) -> Diag<'tcx> {
+    pub(crate) fn thread_local_value_does_not_live_long_enough(&self, span: Span) -> Diag<'infcx> {
         struct_span_code_err!(
             self.dcx(),
             span,
@@ -454,7 +454,7 @@ impl<'tcx> crate::MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         )
     }
 
-    pub(crate) fn temporary_value_borrowed_for_too_long(&self, span: Span) -> Diag<'tcx> {
+    pub(crate) fn temporary_value_borrowed_for_too_long(&self, span: Span) -> Diag<'infcx> {
         struct_span_code_err!(self.dcx(), span, E0716, "temporary value dropped while borrowed",)
     }
 }
diff --git a/compiler/rustc_borrowck/src/dataflow.rs b/compiler/rustc_borrowck/src/dataflow.rs
index f2b5ddcd782..00a30dc2240 100644
--- a/compiler/rustc_borrowck/src/dataflow.rs
+++ b/compiler/rustc_borrowck/src/dataflow.rs
@@ -15,24 +15,24 @@ use std::fmt;
 use crate::{places_conflict, BorrowSet, PlaceConflictBias, PlaceExt, RegionInferenceContext};
 
 /// The results of the dataflow analyses used by the borrow checker.
-pub struct BorrowckResults<'mir, 'tcx> {
-    pub(crate) borrows: Results<'tcx, Borrows<'mir, 'tcx>>,
-    pub(crate) uninits: Results<'tcx, MaybeUninitializedPlaces<'mir, 'tcx>>,
-    pub(crate) ever_inits: Results<'tcx, EverInitializedPlaces<'mir, 'tcx>>,
+pub struct BorrowckResults<'a, 'mir, 'tcx> {
+    pub(crate) borrows: Results<'tcx, Borrows<'a, 'mir, 'tcx>>,
+    pub(crate) uninits: Results<'tcx, MaybeUninitializedPlaces<'a, 'mir, 'tcx>>,
+    pub(crate) ever_inits: Results<'tcx, EverInitializedPlaces<'a, 'mir, 'tcx>>,
 }
 
 /// The transient state of the dataflow analyses used by the borrow checker.
 #[derive(Debug)]
-pub struct BorrowckFlowState<'mir, 'tcx> {
-    pub(crate) borrows: <Borrows<'mir, 'tcx> as AnalysisDomain<'tcx>>::Domain,
-    pub(crate) uninits: <MaybeUninitializedPlaces<'mir, 'tcx> as AnalysisDomain<'tcx>>::Domain,
-    pub(crate) ever_inits: <EverInitializedPlaces<'mir, 'tcx> as AnalysisDomain<'tcx>>::Domain,
+pub struct BorrowckFlowState<'a, 'mir, 'tcx> {
+    pub(crate) borrows: <Borrows<'a, 'mir, 'tcx> as AnalysisDomain<'tcx>>::Domain,
+    pub(crate) uninits: <MaybeUninitializedPlaces<'a, 'mir, 'tcx> as AnalysisDomain<'tcx>>::Domain,
+    pub(crate) ever_inits: <EverInitializedPlaces<'a, 'mir, 'tcx> as AnalysisDomain<'tcx>>::Domain,
 }
 
-impl<'mir, 'tcx> ResultsVisitable<'tcx> for BorrowckResults<'mir, 'tcx> {
+impl<'a, 'mir, 'tcx> ResultsVisitable<'tcx> for BorrowckResults<'a, 'mir, 'tcx> {
     // All three analyses are forward, but we have to use just one here.
-    type Direction = <Borrows<'mir, 'tcx> as AnalysisDomain<'tcx>>::Direction;
-    type FlowState = BorrowckFlowState<'mir, 'tcx>;
+    type Direction = <Borrows<'a, 'mir, 'tcx> as AnalysisDomain<'tcx>>::Direction;
+    type FlowState = BorrowckFlowState<'a, 'mir, 'tcx>;
 
     fn new_flow_state(&self, body: &mir::Body<'tcx>) -> Self::FlowState {
         BorrowckFlowState {
@@ -106,11 +106,11 @@ rustc_index::newtype_index! {
 /// `BorrowIndex`, and maps each such index to a `BorrowData`
 /// describing the borrow. These indexes are used for representing the
 /// borrows in compact bitvectors.
-pub struct Borrows<'mir, 'tcx> {
+pub struct Borrows<'a, 'mir, 'tcx> {
     tcx: TyCtxt<'tcx>,
     body: &'mir Body<'tcx>,
 
-    borrow_set: &'mir BorrowSet<'tcx>,
+    borrow_set: &'a BorrowSet<'tcx>,
     borrows_out_of_scope_at_location: FxIndexMap<Location, Vec<BorrowIndex>>,
 }
 
@@ -389,12 +389,12 @@ impl<'tcx> PoloniusOutOfScopePrecomputer<'_, 'tcx> {
     }
 }
 
-impl<'mir, 'tcx> Borrows<'mir, 'tcx> {
+impl<'a, 'mir, 'tcx> Borrows<'a, 'mir, 'tcx> {
     pub fn new(
         tcx: TyCtxt<'tcx>,
         body: &'mir Body<'tcx>,
-        regioncx: &'mir RegionInferenceContext<'tcx>,
-        borrow_set: &'mir BorrowSet<'tcx>,
+        regioncx: &RegionInferenceContext<'tcx>,
+        borrow_set: &'a BorrowSet<'tcx>,
     ) -> Self {
         let mut borrows_out_of_scope_at_location =
             calculate_borrows_out_of_scope_at_location(body, regioncx, borrow_set);
@@ -494,7 +494,7 @@ impl<'mir, 'tcx> Borrows<'mir, 'tcx> {
     }
 }
 
-impl<'tcx> rustc_mir_dataflow::AnalysisDomain<'tcx> for Borrows<'_, 'tcx> {
+impl<'tcx> rustc_mir_dataflow::AnalysisDomain<'tcx> for Borrows<'_, '_, 'tcx> {
     type Domain = BitSet<BorrowIndex>;
 
     const NAME: &'static str = "borrows";
@@ -517,7 +517,7 @@ impl<'tcx> rustc_mir_dataflow::AnalysisDomain<'tcx> for Borrows<'_, 'tcx> {
 ///   region stops containing the CFG points reachable from the issuing location.
 /// - we also kill loans of conflicting places when overwriting a shared path: e.g. borrows of
 ///   `a.b.c` when `a` is overwritten.
-impl<'tcx> rustc_mir_dataflow::GenKillAnalysis<'tcx> for Borrows<'_, 'tcx> {
+impl<'tcx> rustc_mir_dataflow::GenKillAnalysis<'tcx> for Borrows<'_, '_, 'tcx> {
     type Idx = BorrowIndex;
 
     fn domain_size(&self, _: &mir::Body<'tcx>) -> usize {
@@ -617,8 +617,8 @@ impl<'tcx> rustc_mir_dataflow::GenKillAnalysis<'tcx> for Borrows<'_, 'tcx> {
     }
 }
 
-impl DebugWithContext<Borrows<'_, '_>> for BorrowIndex {
-    fn fmt_with(&self, ctxt: &Borrows<'_, '_>, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+impl DebugWithContext<Borrows<'_, '_, '_>> for BorrowIndex {
+    fn fmt_with(&self, ctxt: &Borrows<'_, '_, '_>, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "{:?}", ctxt.location(*self))
     }
 }
diff --git a/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs b/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs
index d46febffba8..8bf3e670ff2 100644
--- a/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs
@@ -149,13 +149,13 @@ trait TypeOpInfo<'tcx> {
 
     fn base_universe(&self) -> ty::UniverseIndex;
 
-    fn nice_error(
+    fn nice_error<'infcx>(
         &self,
-        mbcx: &mut MirBorrowckCtxt<'_, '_, '_, 'tcx>,
+        mbcx: &mut MirBorrowckCtxt<'_, '_, 'infcx, 'tcx>,
         cause: ObligationCause<'tcx>,
         placeholder_region: ty::Region<'tcx>,
         error_region: Option<ty::Region<'tcx>>,
-    ) -> Option<Diag<'tcx>>;
+    ) -> Option<Diag<'infcx>>;
 
     #[instrument(level = "debug", skip(self, mbcx))]
     fn report_error(
@@ -231,18 +231,25 @@ impl<'tcx> TypeOpInfo<'tcx> for PredicateQuery<'tcx> {
         self.base_universe
     }
 
-    fn nice_error(
+    fn nice_error<'infcx>(
         &self,
-        mbcx: &mut MirBorrowckCtxt<'_, '_, '_, 'tcx>,
+        mbcx: &mut MirBorrowckCtxt<'_, '_, 'infcx, 'tcx>,
         cause: ObligationCause<'tcx>,
         placeholder_region: ty::Region<'tcx>,
         error_region: Option<ty::Region<'tcx>>,
-    ) -> Option<Diag<'tcx>> {
+    ) -> Option<Diag<'infcx>> {
         let (infcx, key, _) =
             mbcx.infcx.tcx.infer_ctxt().build_with_canonical(cause.span, &self.canonical_query);
         let ocx = ObligationCtxt::new(&infcx);
         type_op_prove_predicate_with_cause(&ocx, key, cause);
-        try_extract_error_from_fulfill_cx(&ocx, mbcx.mir_def_id(), placeholder_region, error_region)
+        let diag = try_extract_error_from_fulfill_cx(
+            &ocx,
+            mbcx.mir_def_id(),
+            placeholder_region,
+            error_region,
+        )?
+        .with_dcx(mbcx.dcx());
+        Some(diag)
     }
 }
 
@@ -268,13 +275,13 @@ where
         self.base_universe
     }
 
-    fn nice_error(
+    fn nice_error<'infcx>(
         &self,
-        mbcx: &mut MirBorrowckCtxt<'_, '_, '_, 'tcx>,
+        mbcx: &mut MirBorrowckCtxt<'_, '_, 'infcx, 'tcx>,
         cause: ObligationCause<'tcx>,
         placeholder_region: ty::Region<'tcx>,
         error_region: Option<ty::Region<'tcx>>,
-    ) -> Option<Diag<'tcx>> {
+    ) -> Option<Diag<'infcx>> {
         let (infcx, key, _) =
             mbcx.infcx.tcx.infer_ctxt().build_with_canonical(cause.span, &self.canonical_query);
         let ocx = ObligationCtxt::new(&infcx);
@@ -288,7 +295,14 @@ where
         let (param_env, value) = key.into_parts();
         let _ = ocx.normalize(&cause, param_env, value.value);
 
-        try_extract_error_from_fulfill_cx(&ocx, mbcx.mir_def_id(), placeholder_region, error_region)
+        let diag = try_extract_error_from_fulfill_cx(
+            &ocx,
+            mbcx.mir_def_id(),
+            placeholder_region,
+            error_region,
+        )?
+        .with_dcx(mbcx.dcx());
+        Some(diag)
     }
 }
 
@@ -308,18 +322,25 @@ impl<'tcx> TypeOpInfo<'tcx> for AscribeUserTypeQuery<'tcx> {
         self.base_universe
     }
 
-    fn nice_error(
+    fn nice_error<'infcx>(
         &self,
-        mbcx: &mut MirBorrowckCtxt<'_, '_, '_, 'tcx>,
+        mbcx: &mut MirBorrowckCtxt<'_, '_, 'infcx, 'tcx>,
         cause: ObligationCause<'tcx>,
         placeholder_region: ty::Region<'tcx>,
         error_region: Option<ty::Region<'tcx>>,
-    ) -> Option<Diag<'tcx>> {
+    ) -> Option<Diag<'infcx>> {
         let (infcx, key, _) =
             mbcx.infcx.tcx.infer_ctxt().build_with_canonical(cause.span, &self.canonical_query);
         let ocx = ObligationCtxt::new(&infcx);
         type_op_ascribe_user_type_with_span(&ocx, key, Some(cause.span)).ok()?;
-        try_extract_error_from_fulfill_cx(&ocx, mbcx.mir_def_id(), placeholder_region, error_region)
+        let diag = try_extract_error_from_fulfill_cx(
+            &ocx,
+            mbcx.mir_def_id(),
+            placeholder_region,
+            error_region,
+        )?
+        .with_dcx(mbcx.dcx());
+        Some(diag)
     }
 }
 
@@ -334,13 +355,13 @@ impl<'tcx> TypeOpInfo<'tcx> for crate::type_check::InstantiateOpaqueType<'tcx> {
         self.base_universe.unwrap()
     }
 
-    fn nice_error(
+    fn nice_error<'infcx>(
         &self,
-        mbcx: &mut MirBorrowckCtxt<'_, '_, '_, 'tcx>,
+        mbcx: &mut MirBorrowckCtxt<'_, '_, 'infcx, 'tcx>,
         _cause: ObligationCause<'tcx>,
         placeholder_region: ty::Region<'tcx>,
         error_region: Option<ty::Region<'tcx>>,
-    ) -> Option<Diag<'tcx>> {
+    ) -> Option<Diag<'infcx>> {
         try_extract_error_from_region_constraints(
             mbcx.infcx,
             mbcx.mir_def_id(),
@@ -358,12 +379,12 @@ impl<'tcx> TypeOpInfo<'tcx> for crate::type_check::InstantiateOpaqueType<'tcx> {
 }
 
 #[instrument(skip(ocx), level = "debug")]
-fn try_extract_error_from_fulfill_cx<'tcx>(
-    ocx: &ObligationCtxt<'_, 'tcx>,
+fn try_extract_error_from_fulfill_cx<'a, 'tcx>(
+    ocx: &ObligationCtxt<'a, 'tcx>,
     generic_param_scope: LocalDefId,
     placeholder_region: ty::Region<'tcx>,
     error_region: Option<ty::Region<'tcx>>,
-) -> Option<Diag<'tcx>> {
+) -> Option<Diag<'a>> {
     // We generally shouldn't have errors here because the query was
     // already run, but there's no point using `span_delayed_bug`
     // when we're going to emit an error here anyway.
@@ -381,15 +402,15 @@ fn try_extract_error_from_fulfill_cx<'tcx>(
 }
 
 #[instrument(level = "debug", skip(infcx, region_var_origin, universe_of_region))]
-fn try_extract_error_from_region_constraints<'tcx>(
-    infcx: &InferCtxt<'tcx>,
+fn try_extract_error_from_region_constraints<'a, 'tcx>(
+    infcx: &'a InferCtxt<'tcx>,
     generic_param_scope: LocalDefId,
     placeholder_region: ty::Region<'tcx>,
     error_region: Option<ty::Region<'tcx>>,
     region_constraints: &RegionConstraintData<'tcx>,
     mut region_var_origin: impl FnMut(RegionVid) -> RegionVariableOrigin,
     mut universe_of_region: impl FnMut(RegionVid) -> UniverseIndex,
-) -> Option<Diag<'tcx>> {
+) -> Option<Diag<'a>> {
     let placeholder_universe = match placeholder_region.kind() {
         ty::RePlaceholder(p) => p.universe,
         ty::ReVar(vid) => universe_of_region(vid),
diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
index c26bbb926ea..44ab762f66e 100644
--- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
@@ -73,7 +73,7 @@ enum StorageDeadOrDrop<'tcx> {
     Destructor(Ty<'tcx>),
 }
 
-impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
+impl<'infcx, 'tcx> MirBorrowckCtxt<'_, '_, 'infcx, 'tcx> {
     pub(crate) fn report_use_of_moved_or_uninitialized(
         &mut self,
         location: Location,
@@ -341,7 +341,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
     fn suggest_ref_or_clone(
         &self,
         mpi: MovePathIndex,
-        err: &mut Diag<'tcx>,
+        err: &mut Diag<'infcx>,
         in_pattern: &mut bool,
         move_spans: UseSpans<'tcx>,
     ) {
@@ -517,7 +517,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         desired_action: InitializationRequiringAction,
         span: Span,
         use_spans: UseSpans<'tcx>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         // We need all statements in the body where the binding was assigned to later find all
         // the branching code paths where the binding *wasn't* assigned to.
         let inits = &self.move_data.init_path_map[mpi];
@@ -1461,7 +1461,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         location: Location,
         (place, _span): (Place<'tcx>, Span),
         borrow: &BorrowData<'tcx>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         let borrow_spans = self.retrieve_borrow_spans(borrow);
         let borrow_span = borrow_spans.args_or_use();
 
@@ -1511,7 +1511,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         (place, span): (Place<'tcx>, Span),
         gen_borrow_kind: BorrowKind,
         issued_borrow: &BorrowData<'tcx>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         let issued_spans = self.retrieve_borrow_spans(issued_borrow);
         let issued_span = issued_spans.args_or_use();
 
@@ -1802,7 +1802,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         err
     }
 
-    fn suggest_copy_for_type_in_cloned_ref(&self, err: &mut Diag<'tcx>, place: Place<'tcx>) {
+    fn suggest_copy_for_type_in_cloned_ref(&self, err: &mut Diag<'infcx>, place: Place<'tcx>) {
         let tcx = self.infcx.tcx;
         let hir = tcx.hir();
         let Some(body_id) = tcx.hir_node(self.mir_hir_id()).body_id() else { return };
@@ -2861,7 +2861,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         drop_span: Span,
         borrow_spans: UseSpans<'tcx>,
         explanation: BorrowExplanation<'tcx>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         debug!(
             "report_local_value_does_not_live_long_enough(\
              {:?}, {:?}, {:?}, {:?}, {:?}\
@@ -3036,7 +3036,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         &self,
         drop_span: Span,
         borrow_span: Span,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         debug!(
             "report_thread_local_value_does_not_live_long_enough(\
              {:?}, {:?}\
@@ -3061,7 +3061,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         borrow_spans: UseSpans<'tcx>,
         proper_span: Span,
         explanation: BorrowExplanation<'tcx>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         if let BorrowExplanation::MustBeValidFor { category, span, from_closure: false, .. } =
             explanation
         {
@@ -3226,7 +3226,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         return_span: Span,
         category: ConstraintCategory<'tcx>,
         opt_place_desc: Option<&String>,
-    ) -> Result<(), Diag<'tcx>> {
+    ) -> Result<(), Diag<'infcx>> {
         let return_kind = match category {
             ConstraintCategory::Return(_) => "return",
             ConstraintCategory::Yield => "yield",
@@ -3319,7 +3319,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         constraint_span: Span,
         captured_var: &str,
         scope: &str,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         let tcx = self.infcx.tcx;
         let args_span = use_span.args_or_use();
 
@@ -3431,7 +3431,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         upvar_span: Span,
         upvar_name: Symbol,
         escape_span: Span,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         let tcx = self.infcx.tcx;
 
         let escapes_from = tcx.def_descr(self.mir_def_id().to_def_id());
diff --git a/compiler/rustc_borrowck/src/diagnostics/mod.rs b/compiler/rustc_borrowck/src/diagnostics/mod.rs
index 842ed38f1e2..4567a014fe8 100644
--- a/compiler/rustc_borrowck/src/diagnostics/mod.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/mod.rs
@@ -69,7 +69,7 @@ pub(super) struct DescribePlaceOpt {
 
 pub(super) struct IncludingTupleField(pub(super) bool);
 
-impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
+impl<'infcx, 'tcx> MirBorrowckCtxt<'_, '_, 'infcx, 'tcx> {
     /// Adds a suggestion when a closure is invoked twice with a moved variable or when a closure
     /// is moved after being invoked.
     ///
@@ -86,7 +86,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         &self,
         location: Location,
         place: PlaceRef<'tcx>,
-        diag: &mut Diag<'_>,
+        diag: &mut Diag<'infcx>,
     ) -> bool {
         debug!("add_moved_or_invoked_closure_note: location={:?} place={:?}", location, place);
         let mut target = place.local_or_deref_local();
diff --git a/compiler/rustc_borrowck/src/diagnostics/move_errors.rs b/compiler/rustc_borrowck/src/diagnostics/move_errors.rs
index 407b83d4977..c817a80a541 100644
--- a/compiler/rustc_borrowck/src/diagnostics/move_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/move_errors.rs
@@ -93,7 +93,7 @@ enum GroupedMoveError<'tcx> {
     },
 }
 
-impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
+impl<'infcx, 'tcx> MirBorrowckCtxt<'_, '_, 'infcx, 'tcx> {
     pub(crate) fn report_move_errors(&mut self) {
         let grouped_errors = self.group_move_errors();
         for error in grouped_errors {
@@ -291,7 +291,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         self.buffer_error(err);
     }
 
-    fn report_cannot_move_from_static(&mut self, place: Place<'tcx>, span: Span) -> Diag<'tcx> {
+    fn report_cannot_move_from_static(&mut self, place: Place<'tcx>, span: Span) -> Diag<'infcx> {
         let description = if place.projection.len() == 1 {
             format!("static item {}", self.describe_any_place(place.as_ref()))
         } else {
@@ -428,7 +428,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         deref_target_place: Place<'tcx>,
         span: Span,
         use_spans: Option<UseSpans<'tcx>>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         let tcx = self.infcx.tcx;
         // Inspect the type of the content behind the
         // borrow to provide feedback about why this
diff --git a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
index 93fac3181ba..19a4df0cd7b 100644
--- a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
@@ -30,7 +30,7 @@ pub(crate) enum AccessKind {
     Mutate,
 }
 
-impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
+impl<'infcx, 'tcx> MirBorrowckCtxt<'_, '_, 'infcx, 'tcx> {
     pub(crate) fn report_mutability_error(
         &mut self,
         access_place: Place<'tcx>,
@@ -541,7 +541,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
     }
 
     /// Suggest `map[k] = v` => `map.insert(k, v)` and the like.
-    fn suggest_map_index_mut_alternatives(&self, ty: Ty<'tcx>, err: &mut Diag<'tcx>, span: Span) {
+    fn suggest_map_index_mut_alternatives(&self, ty: Ty<'tcx>, err: &mut Diag<'infcx>, span: Span) {
         let Some(adt) = ty.ty_adt_def() else { return };
         let did = adt.did();
         if self.infcx.tcx.is_diagnostic_item(sym::HashMap, did)
@@ -550,13 +550,13 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
             /// Walks through the HIR, looking for the corresponding span for this error.
             /// When it finds it, see if it corresponds to assignment operator whose LHS
             /// is an index expr.
-            struct SuggestIndexOperatorAlternativeVisitor<'a, 'tcx> {
+            struct SuggestIndexOperatorAlternativeVisitor<'a, 'infcx, 'tcx> {
                 assign_span: Span,
-                err: &'a mut Diag<'tcx>,
+                err: &'a mut Diag<'infcx>,
                 ty: Ty<'tcx>,
                 suggested: bool,
             }
-            impl<'a, 'tcx> Visitor<'tcx> for SuggestIndexOperatorAlternativeVisitor<'a, 'tcx> {
+            impl<'a, 'cx, 'tcx> Visitor<'tcx> for SuggestIndexOperatorAlternativeVisitor<'a, 'cx, 'tcx> {
                 fn visit_stmt(&mut self, stmt: &'tcx hir::Stmt<'tcx>) {
                     hir::intravisit::walk_stmt(self, stmt);
                     let expr = match stmt.kind {
diff --git a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
index db78edc45b9..fba18c38146 100644
--- a/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
@@ -160,7 +160,7 @@ pub struct ErrorConstraintInfo<'tcx> {
     pub(super) span: Span,
 }
 
-impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
+impl<'infcx, 'tcx> MirBorrowckCtxt<'_, '_, 'infcx, 'tcx> {
     /// Converts a region inference variable into a `ty::Region` that
     /// we can use for error reporting. If `r` is universally bound,
     /// then we use the name that we have on record for it. If `r` is
@@ -360,7 +360,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
                     let named_key = self.regioncx.name_regions(self.infcx.tcx, key);
                     let named_region = self.regioncx.name_regions(self.infcx.tcx, member_region);
                     let diag = unexpected_hidden_region_diagnostic(
-                        self.infcx.tcx,
+                        self.infcx,
                         self.mir_def_id(),
                         span,
                         named_ty,
@@ -589,7 +589,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
         &self,
         errci: &ErrorConstraintInfo<'tcx>,
         kind: ReturnConstraint,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'infcx> {
         let ErrorConstraintInfo { outlived_fr, span, .. } = errci;
 
         let mut output_ty = self.regioncx.universal_regions().unnormalized_output_ty;
@@ -658,7 +658,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
     ///    |     ^^^^^^^^^^ `x` escapes the function body here
     /// ```
     #[instrument(level = "debug", skip(self))]
-    fn report_escaping_data_error(&self, errci: &ErrorConstraintInfo<'tcx>) -> Diag<'tcx> {
+    fn report_escaping_data_error(&self, errci: &ErrorConstraintInfo<'tcx>) -> Diag<'infcx> {
         let ErrorConstraintInfo { span, category, .. } = errci;
 
         let fr_name_and_span = self.regioncx.get_var_name_and_span_for_region(
@@ -767,7 +767,7 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
     ///    |                    is returning data with lifetime `'b`
     /// ```
     #[allow(rustc::diagnostic_outside_of_impl)] // FIXME
-    fn report_general_error(&self, errci: &ErrorConstraintInfo<'tcx>) -> Diag<'tcx> {
+    fn report_general_error(&self, errci: &ErrorConstraintInfo<'tcx>) -> Diag<'infcx> {
         let ErrorConstraintInfo {
             fr,
             fr_is_local,
diff --git a/compiler/rustc_borrowck/src/lib.rs b/compiler/rustc_borrowck/src/lib.rs
index 69efee2fbdc..e6f8ffd428d 100644
--- a/compiler/rustc_borrowck/src/lib.rs
+++ b/compiler/rustc_borrowck/src/lib.rs
@@ -310,8 +310,8 @@ fn do_mir_borrowck<'tcx>(
         promoted_mbcx.report_move_errors();
         diags = promoted_mbcx.diags;
 
-        struct MoveVisitor<'a, 'b, 'mir, 'cx, 'tcx> {
-            ctxt: &'a mut MirBorrowckCtxt<'b, 'mir, 'cx, 'tcx>,
+        struct MoveVisitor<'a, 'b, 'mir, 'infcx, 'tcx> {
+            ctxt: &'a mut MirBorrowckCtxt<'b, 'mir, 'infcx, 'tcx>,
         }
 
         impl<'tcx> Visitor<'tcx> for MoveVisitor<'_, '_, '_, '_, 'tcx> {
@@ -528,8 +528,8 @@ impl<'tcx> Deref for BorrowckInferCtxt<'tcx> {
     }
 }
 
-struct MirBorrowckCtxt<'a, 'mir, 'cx, 'tcx> {
-    infcx: &'cx BorrowckInferCtxt<'tcx>,
+struct MirBorrowckCtxt<'a, 'mir, 'infcx, 'tcx> {
+    infcx: &'infcx BorrowckInferCtxt<'tcx>,
     param_env: ParamEnv<'tcx>,
     body: &'mir Body<'tcx>,
     move_data: &'a MoveData<'tcx>,
@@ -596,7 +596,7 @@ struct MirBorrowckCtxt<'a, 'mir, 'cx, 'tcx> {
     /// Results of Polonius analysis.
     polonius_output: Option<Rc<PoloniusOutput>>,
 
-    diags: diags::BorrowckDiags<'tcx>,
+    diags: diags::BorrowckDiags<'infcx, 'tcx>,
     move_errors: Vec<MoveError<'tcx>>,
 }
 
@@ -605,15 +605,15 @@ struct MirBorrowckCtxt<'a, 'mir, 'cx, 'tcx> {
 // 2. loans made in overlapping scopes do not conflict
 // 3. assignments do not affect things loaned out as immutable
 // 4. moves do not affect things loaned out in any way
-impl<'mir, 'tcx, R> rustc_mir_dataflow::ResultsVisitor<'mir, 'tcx, R>
-    for MirBorrowckCtxt<'_, 'mir, '_, 'tcx>
+impl<'a, 'mir, 'tcx, R> rustc_mir_dataflow::ResultsVisitor<'mir, 'tcx, R>
+    for MirBorrowckCtxt<'a, 'mir, '_, 'tcx>
 {
-    type FlowState = Flows<'mir, 'tcx>;
+    type FlowState = Flows<'a, 'mir, 'tcx>;
 
     fn visit_statement_before_primary_effect(
         &mut self,
         _results: &mut R,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
         stmt: &'mir Statement<'tcx>,
         location: Location,
     ) {
@@ -683,7 +683,7 @@ impl<'mir, 'tcx, R> rustc_mir_dataflow::ResultsVisitor<'mir, 'tcx, R>
     fn visit_terminator_before_primary_effect(
         &mut self,
         _results: &mut R,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
         term: &'mir Terminator<'tcx>,
         loc: Location,
     ) {
@@ -794,7 +794,7 @@ impl<'mir, 'tcx, R> rustc_mir_dataflow::ResultsVisitor<'mir, 'tcx, R>
     fn visit_terminator_after_primary_effect(
         &mut self,
         _results: &mut R,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
         term: &'mir Terminator<'tcx>,
         loc: Location,
     ) {
@@ -988,7 +988,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         place_span: (Place<'tcx>, Span),
         kind: (AccessDepth, ReadOrWrite),
         is_local_mutation_allowed: LocalMutationIsAllowed,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) {
         let (sd, rw) = kind;
 
@@ -1038,7 +1038,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         place_span: (Place<'tcx>, Span),
         sd: AccessDepth,
         rw: ReadOrWrite,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) -> bool {
         let mut error_reported = false;
         let borrow_set = Rc::clone(&self.borrow_set);
@@ -1179,7 +1179,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         location: Location,
         place_span: (Place<'tcx>, Span),
         kind: AccessDepth,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) {
         // Write of P[i] or *P requires P init'd.
         self.check_if_assigned_path_is_moved(location, place_span, flow_state);
@@ -1197,7 +1197,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         &mut self,
         location: Location,
         (rvalue, span): (&'mir Rvalue<'tcx>, Span),
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) {
         match rvalue {
             &Rvalue::Ref(_ /*rgn*/, bk, place) => {
@@ -1455,7 +1455,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         &mut self,
         location: Location,
         (operand, span): (&'mir Operand<'tcx>, Span),
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) {
         match *operand {
             Operand::Copy(place) => {
@@ -1579,7 +1579,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         &mut self,
         location: Location,
         span: Span,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) {
         // Two-phase borrow support: For each activation that is newly
         // generated at this statement, check if it interferes with
@@ -1743,7 +1743,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         location: Location,
         desired_action: InitializationRequiringAction,
         place_span: (PlaceRef<'tcx>, Span),
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) {
         let maybe_uninits = &flow_state.uninits;
 
@@ -1848,7 +1848,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         location: Location,
         desired_action: InitializationRequiringAction,
         place_span: (PlaceRef<'tcx>, Span),
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) {
         let maybe_uninits = &flow_state.uninits;
 
@@ -1947,7 +1947,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         &mut self,
         location: Location,
         (place, span): (Place<'tcx>, Span),
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) {
         debug!("check_if_assigned_path_is_moved place: {:?}", place);
 
@@ -2013,7 +2013,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
             location: Location,
             base: PlaceRef<'tcx>,
             span: Span,
-            flow_state: &Flows<'mir, 'tcx>,
+            flow_state: &Flows<'_, 'mir, 'tcx>,
         ) {
             // rust-lang/rust#21232: Until Rust allows reads from the
             // initialized parts of partially initialized structs, we
@@ -2104,7 +2104,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
         (place, span): (Place<'tcx>, Span),
         kind: ReadOrWrite,
         is_local_mutation_allowed: LocalMutationIsAllowed,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
         location: Location,
     ) -> bool {
         debug!(
@@ -2220,7 +2220,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
     fn is_local_ever_initialized(
         &self,
         local: Local,
-        flow_state: &Flows<'mir, 'tcx>,
+        flow_state: &Flows<'_, 'mir, 'tcx>,
     ) -> Option<InitIndex> {
         let mpi = self.move_data.rev_lookup.find_local(local)?;
         let ii = &self.move_data.init_path_map[mpi];
@@ -2228,7 +2228,7 @@ impl<'mir, 'tcx> MirBorrowckCtxt<'_, 'mir, '_, 'tcx> {
     }
 
     /// Adds the place into the used mutable variables set
-    fn add_used_mut(&mut self, root_place: RootPlace<'tcx>, flow_state: &Flows<'mir, 'tcx>) {
+    fn add_used_mut(&mut self, root_place: RootPlace<'tcx>, flow_state: &Flows<'_, 'mir, 'tcx>) {
         match root_place {
             RootPlace { place_local: local, place_projection: [], is_local_mutation_allowed } => {
                 // If the local may have been initialized, and it is now currently being
@@ -2428,12 +2428,12 @@ mod diags {
 
     use super::*;
 
-    enum BufferedDiag<'tcx> {
-        Error(Diag<'tcx>),
-        NonError(Diag<'tcx, ()>),
+    enum BufferedDiag<'infcx> {
+        Error(Diag<'infcx>),
+        NonError(Diag<'infcx, ()>),
     }
 
-    impl<'tcx> BufferedDiag<'tcx> {
+    impl<'infcx> BufferedDiag<'infcx> {
         fn sort_span(&self) -> Span {
             match self {
                 BufferedDiag::Error(diag) => diag.sort_span,
@@ -2442,7 +2442,7 @@ mod diags {
         }
     }
 
-    pub struct BorrowckDiags<'tcx> {
+    pub struct BorrowckDiags<'infcx, 'tcx> {
         /// This field keeps track of move errors that are to be reported for given move indices.
         ///
         /// There are situations where many errors can be reported for a single move out (see
@@ -2457,15 +2457,15 @@ mod diags {
         /// `BTreeMap` is used to preserve the order of insertions when iterating. This is necessary
         /// when errors in the map are being re-added to the error buffer so that errors with the
         /// same primary span come out in a consistent order.
-        buffered_move_errors: BTreeMap<Vec<MoveOutIndex>, (PlaceRef<'tcx>, Diag<'tcx>)>,
+        buffered_move_errors: BTreeMap<Vec<MoveOutIndex>, (PlaceRef<'tcx>, Diag<'infcx>)>,
 
-        buffered_mut_errors: FxIndexMap<Span, (Diag<'tcx>, usize)>,
+        buffered_mut_errors: FxIndexMap<Span, (Diag<'infcx>, usize)>,
 
         /// Buffer of diagnostics to be reported. A mixture of error and non-error diagnostics.
-        buffered_diags: Vec<BufferedDiag<'tcx>>,
+        buffered_diags: Vec<BufferedDiag<'infcx>>,
     }
 
-    impl<'tcx> BorrowckDiags<'tcx> {
+    impl<'infcx, 'tcx> BorrowckDiags<'infcx, 'tcx> {
         pub fn new() -> Self {
             BorrowckDiags {
                 buffered_move_errors: BTreeMap::new(),
@@ -2474,28 +2474,28 @@ mod diags {
             }
         }
 
-        pub fn buffer_error(&mut self, diag: Diag<'tcx>) {
+        pub fn buffer_error(&mut self, diag: Diag<'infcx>) {
             self.buffered_diags.push(BufferedDiag::Error(diag));
         }
 
-        pub fn buffer_non_error(&mut self, diag: Diag<'tcx, ()>) {
+        pub fn buffer_non_error(&mut self, diag: Diag<'infcx, ()>) {
             self.buffered_diags.push(BufferedDiag::NonError(diag));
         }
     }
 
-    impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
-        pub fn buffer_error(&mut self, diag: Diag<'tcx>) {
+    impl<'infcx, 'tcx> MirBorrowckCtxt<'_, '_, 'infcx, 'tcx> {
+        pub fn buffer_error(&mut self, diag: Diag<'infcx>) {
             self.diags.buffer_error(diag);
         }
 
-        pub fn buffer_non_error(&mut self, diag: Diag<'tcx, ()>) {
+        pub fn buffer_non_error(&mut self, diag: Diag<'infcx, ()>) {
             self.diags.buffer_non_error(diag);
         }
 
         pub fn buffer_move_error(
             &mut self,
             move_out_indices: Vec<MoveOutIndex>,
-            place_and_err: (PlaceRef<'tcx>, Diag<'tcx>),
+            place_and_err: (PlaceRef<'tcx>, Diag<'infcx>),
         ) -> bool {
             if let Some((_, diag)) =
                 self.diags.buffered_move_errors.insert(move_out_indices, place_and_err)
@@ -2508,12 +2508,12 @@ mod diags {
             }
         }
 
-        pub fn get_buffered_mut_error(&mut self, span: Span) -> Option<(Diag<'tcx>, usize)> {
+        pub fn get_buffered_mut_error(&mut self, span: Span) -> Option<(Diag<'infcx>, usize)> {
             // FIXME(#120456) - is `swap_remove` correct?
             self.diags.buffered_mut_errors.swap_remove(&span)
         }
 
-        pub fn buffer_mut_error(&mut self, span: Span, diag: Diag<'tcx>, count: usize) {
+        pub fn buffer_mut_error(&mut self, span: Span, diag: Diag<'infcx>, count: usize) {
             self.diags.buffered_mut_errors.insert(span, (diag, count));
         }
 
@@ -2554,7 +2554,7 @@ mod diags {
         pub fn has_move_error(
             &self,
             move_out_indices: &[MoveOutIndex],
-        ) -> Option<&(PlaceRef<'tcx>, Diag<'tcx>)> {
+        ) -> Option<&(PlaceRef<'tcx>, Diag<'infcx>)> {
             self.diags.buffered_move_errors.get(move_out_indices)
         }
     }
diff --git a/compiler/rustc_borrowck/src/nll.rs b/compiler/rustc_borrowck/src/nll.rs
index 923cf7e9405..2ffa9ba5b4d 100644
--- a/compiler/rustc_borrowck/src/nll.rs
+++ b/compiler/rustc_borrowck/src/nll.rs
@@ -81,7 +81,7 @@ pub(crate) fn compute_regions<'cx, 'tcx>(
     promoted: &IndexSlice<Promoted, Body<'tcx>>,
     location_table: &LocationTable,
     param_env: ty::ParamEnv<'tcx>,
-    flow_inits: &mut ResultsCursor<'cx, 'tcx, MaybeInitializedPlaces<'cx, 'tcx>>,
+    flow_inits: &mut ResultsCursor<'cx, 'tcx, MaybeInitializedPlaces<'_, 'cx, 'tcx>>,
     move_data: &MoveData<'tcx>,
     borrow_set: &BorrowSet<'tcx>,
     upvars: &[&ty::CapturedPlace<'tcx>],
@@ -262,13 +262,13 @@ pub(super) fn dump_mir_results<'tcx>(
 
 #[allow(rustc::diagnostic_outside_of_impl)]
 #[allow(rustc::untranslatable_diagnostic)]
-pub(super) fn dump_annotation<'tcx>(
-    infcx: &BorrowckInferCtxt<'tcx>,
+pub(super) fn dump_annotation<'tcx, 'cx>(
+    infcx: &'cx BorrowckInferCtxt<'tcx>,
     body: &Body<'tcx>,
     regioncx: &RegionInferenceContext<'tcx>,
     closure_region_requirements: &Option<ClosureRegionRequirements<'tcx>>,
     opaque_type_values: &FxIndexMap<LocalDefId, OpaqueHiddenType<'tcx>>,
-    diags: &mut crate::diags::BorrowckDiags<'tcx>,
+    diags: &mut crate::diags::BorrowckDiags<'cx, 'tcx>,
 ) {
     let tcx = infcx.tcx;
     let base_def_id = tcx.typeck_root_def_id(body.source.def_id());
@@ -285,7 +285,7 @@ pub(super) fn dump_annotation<'tcx>(
 
     let def_span = tcx.def_span(body.source.def_id());
     let mut err = if let Some(closure_region_requirements) = closure_region_requirements {
-        let mut err = tcx.dcx().struct_span_note(def_span, "external requirements");
+        let mut err = infcx.dcx().struct_span_note(def_span, "external requirements");
 
         regioncx.annotate(tcx, &mut err);
 
@@ -304,7 +304,7 @@ pub(super) fn dump_annotation<'tcx>(
 
         err
     } else {
-        let mut err = tcx.dcx().struct_span_note(def_span, "no external requirements");
+        let mut err = infcx.dcx().struct_span_note(def_span, "no external requirements");
         regioncx.annotate(tcx, &mut err);
 
         err
diff --git a/compiler/rustc_borrowck/src/region_infer/opaque_types.rs b/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
index 67e5c8352df..e195ceded1b 100644
--- a/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
+++ b/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
@@ -285,7 +285,7 @@ impl<'tcx> InferCtxt<'tcx> {
         }
 
         if let Err(guar) =
-            check_opaque_type_parameter_valid(self.tcx, opaque_type_key, instantiated_ty.span)
+            check_opaque_type_parameter_valid(self, opaque_type_key, instantiated_ty.span)
         {
             return Ty::new_error(self.tcx, guar);
         }
@@ -294,6 +294,10 @@ impl<'tcx> InferCtxt<'tcx> {
             .remap_generic_params_to_declaration_params(opaque_type_key, self.tcx, false)
             .ty;
 
+        if let Err(e) = definition_ty.error_reported() {
+            return Ty::new_error(self.tcx, e);
+        }
+
         // `definition_ty` does not live in of the current inference context,
         // so lets make sure that we don't accidentally misuse our current `infcx`.
         match check_opaque_type_well_formed(
@@ -387,10 +391,11 @@ fn check_opaque_type_well_formed<'tcx>(
 /// [rustc-dev-guide chapter]:
 /// https://rustc-dev-guide.rust-lang.org/opaque-types-region-infer-restrictions.html
 fn check_opaque_type_parameter_valid<'tcx>(
-    tcx: TyCtxt<'tcx>,
+    infcx: &InferCtxt<'tcx>,
     opaque_type_key: OpaqueTypeKey<'tcx>,
     span: Span,
 ) -> Result<(), ErrorGuaranteed> {
+    let tcx = infcx.tcx;
     let opaque_generics = tcx.generics_of(opaque_type_key.def_id);
     let opaque_env = LazyOpaqueTyEnv::new(tcx, opaque_type_key.def_id);
     let mut seen_params: FxIndexMap<_, Vec<_>> = FxIndexMap::default();
@@ -420,7 +425,7 @@ fn check_opaque_type_parameter_valid<'tcx>(
 
             opaque_env.param_is_error(i)?;
 
-            return Err(tcx.dcx().emit_err(NonGenericOpaqueTypeParam {
+            return Err(infcx.dcx().emit_err(NonGenericOpaqueTypeParam {
                 ty: arg,
                 kind,
                 span,
@@ -438,7 +443,7 @@ fn check_opaque_type_parameter_valid<'tcx>(
                 .collect();
             #[allow(rustc::diagnostic_outside_of_impl)]
             #[allow(rustc::untranslatable_diagnostic)]
-            return Err(tcx
+            return Err(infcx
                 .dcx()
                 .struct_span_err(span, "non-defining opaque type use in defining scope")
                 .with_span_note(spans, format!("{descr} used multiple times"))
diff --git a/compiler/rustc_borrowck/src/type_check/liveness/mod.rs b/compiler/rustc_borrowck/src/type_check/liveness/mod.rs
index b777e01f7a6..6d6425b5f19 100644
--- a/compiler/rustc_borrowck/src/type_check/liveness/mod.rs
+++ b/compiler/rustc_borrowck/src/type_check/liveness/mod.rs
@@ -34,7 +34,7 @@ pub(super) fn generate<'mir, 'tcx>(
     typeck: &mut TypeChecker<'_, 'tcx>,
     body: &Body<'tcx>,
     elements: &Rc<DenseLocationMap>,
-    flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'mir, 'tcx>>,
+    flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'_, 'mir, 'tcx>>,
     move_data: &MoveData<'tcx>,
 ) {
     debug!("liveness::generate");
diff --git a/compiler/rustc_borrowck/src/type_check/liveness/trace.rs b/compiler/rustc_borrowck/src/type_check/liveness/trace.rs
index 359c4ea0eb1..eb86c8d06f1 100644
--- a/compiler/rustc_borrowck/src/type_check/liveness/trace.rs
+++ b/compiler/rustc_borrowck/src/type_check/liveness/trace.rs
@@ -43,7 +43,7 @@ pub(super) fn trace<'mir, 'tcx>(
     typeck: &mut TypeChecker<'_, 'tcx>,
     body: &Body<'tcx>,
     elements: &Rc<DenseLocationMap>,
-    flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'mir, 'tcx>>,
+    flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'_, 'mir, 'tcx>>,
     move_data: &MoveData<'tcx>,
     relevant_live_locals: Vec<Local>,
     boring_locals: Vec<Local>,
@@ -101,7 +101,7 @@ pub(super) fn trace<'mir, 'tcx>(
 }
 
 /// Contextual state for the type-liveness coroutine.
-struct LivenessContext<'me, 'typeck, 'flow, 'tcx> {
+struct LivenessContext<'a, 'me, 'typeck, 'flow, 'tcx> {
     /// Current type-checker, giving us our inference context etc.
     typeck: &'me mut TypeChecker<'typeck, 'tcx>,
 
@@ -119,7 +119,7 @@ struct LivenessContext<'me, 'typeck, 'flow, 'tcx> {
 
     /// Results of dataflow tracking which variables (and paths) have been
     /// initialized.
-    flow_inits: &'me mut ResultsCursor<'flow, 'tcx, MaybeInitializedPlaces<'flow, 'tcx>>,
+    flow_inits: &'me mut ResultsCursor<'flow, 'tcx, MaybeInitializedPlaces<'a, 'flow, 'tcx>>,
 
     /// Index indicating where each variable is assigned, used, or
     /// dropped.
@@ -131,8 +131,8 @@ struct DropData<'tcx> {
     region_constraint_data: Option<&'tcx QueryRegionConstraints<'tcx>>,
 }
 
-struct LivenessResults<'me, 'typeck, 'flow, 'tcx> {
-    cx: LivenessContext<'me, 'typeck, 'flow, 'tcx>,
+struct LivenessResults<'a, 'me, 'typeck, 'flow, 'tcx> {
+    cx: LivenessContext<'a, 'me, 'typeck, 'flow, 'tcx>,
 
     /// Set of points that define the current local.
     defs: BitSet<PointIndex>,
@@ -153,8 +153,8 @@ struct LivenessResults<'me, 'typeck, 'flow, 'tcx> {
     stack: Vec<PointIndex>,
 }
 
-impl<'me, 'typeck, 'flow, 'tcx> LivenessResults<'me, 'typeck, 'flow, 'tcx> {
-    fn new(cx: LivenessContext<'me, 'typeck, 'flow, 'tcx>) -> Self {
+impl<'a, 'me, 'typeck, 'flow, 'tcx> LivenessResults<'a, 'me, 'typeck, 'flow, 'tcx> {
+    fn new(cx: LivenessContext<'a, 'me, 'typeck, 'flow, 'tcx>) -> Self {
         let num_points = cx.elements.num_points();
         LivenessResults {
             cx,
@@ -507,7 +507,7 @@ impl<'me, 'typeck, 'flow, 'tcx> LivenessResults<'me, 'typeck, 'flow, 'tcx> {
     }
 }
 
-impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> {
+impl<'tcx> LivenessContext<'_, '_, '_, '_, 'tcx> {
     /// Returns `true` if the local variable (or some part of it) is initialized at the current
     /// cursor position. Callers should call one of the `seek` methods immediately before to point
     /// the cursor to the desired location.
diff --git a/compiler/rustc_borrowck/src/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs
index 81bde14a82f..aa25e3adf28 100644
--- a/compiler/rustc_borrowck/src/type_check/mod.rs
+++ b/compiler/rustc_borrowck/src/type_check/mod.rs
@@ -129,7 +129,7 @@ pub(crate) fn type_check<'mir, 'tcx>(
     location_table: &LocationTable,
     borrow_set: &BorrowSet<'tcx>,
     all_facts: &mut Option<AllFacts>,
-    flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'mir, 'tcx>>,
+    flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'_, 'mir, 'tcx>>,
     move_data: &MoveData<'tcx>,
     elements: &Rc<DenseLocationMap>,
     upvars: &[&ty::CapturedPlace<'tcx>],
diff --git a/compiler/rustc_borrowck/src/used_muts.rs b/compiler/rustc_borrowck/src/used_muts.rs
index 25e1f6268e0..e2de6b8b4a9 100644
--- a/compiler/rustc_borrowck/src/used_muts.rs
+++ b/compiler/rustc_borrowck/src/used_muts.rs
@@ -45,10 +45,10 @@ impl<'tcx> MirBorrowckCtxt<'_, '_, '_, 'tcx> {
 
 /// MIR visitor for collecting used mutable variables.
 /// The 'visit lifetime represents the duration of the MIR walk.
-struct GatherUsedMutsVisitor<'visit, 'a, 'mir, 'cx, 'tcx> {
+struct GatherUsedMutsVisitor<'visit, 'a, 'mir, 'infcx, 'tcx> {
     temporary_used_locals: FxIndexSet<Local>,
     never_initialized_mut_locals: &'visit mut FxIndexSet<Local>,
-    mbcx: &'visit mut MirBorrowckCtxt<'a, 'mir, 'cx, 'tcx>,
+    mbcx: &'visit mut MirBorrowckCtxt<'a, 'mir, 'infcx, 'tcx>,
 }
 
 impl GatherUsedMutsVisitor<'_, '_, '_, '_, '_> {
diff --git a/compiler/rustc_errors/src/diagnostic.rs b/compiler/rustc_errors/src/diagnostic.rs
index e580910af77..d500f6d88a0 100644
--- a/compiler/rustc_errors/src/diagnostic.rs
+++ b/compiler/rustc_errors/src/diagnostic.rs
@@ -510,7 +510,7 @@ pub struct Diag<'a, G: EmissionGuarantee = ErrorGuaranteed> {
 // would be bad.
 impl<G> !Clone for Diag<'_, G> {}
 
-rustc_data_structures::static_assert_size!(Diag<'_, ()>, 2 * std::mem::size_of::<usize>());
+rustc_data_structures::static_assert_size!(Diag<'_, ()>, 3 * std::mem::size_of::<usize>());
 
 impl<G: EmissionGuarantee> Deref for Diag<'_, G> {
     type Target = DiagInner;
@@ -582,6 +582,11 @@ impl<'a, G: EmissionGuarantee> Diag<'a, G> {
         Self::new_diagnostic(dcx, DiagInner::new(level, message))
     }
 
+    /// Allow moving diagnostics between different error tainting contexts
+    pub fn with_dcx(mut self, dcx: DiagCtxtHandle<'_>) -> Diag<'_, G> {
+        Diag { dcx, diag: self.diag.take(), _marker: PhantomData }
+    }
+
     /// Creates a new `Diag` with an already constructed diagnostic.
     #[track_caller]
     pub(crate) fn new_diagnostic(dcx: DiagCtxtHandle<'a>, diag: DiagInner) -> Self {
diff --git a/compiler/rustc_errors/src/lib.rs b/compiler/rustc_errors/src/lib.rs
index 91112a57277..2086d4030f9 100644
--- a/compiler/rustc_errors/src/lib.rs
+++ b/compiler/rustc_errors/src/lib.rs
@@ -63,6 +63,7 @@ use rustc_span::source_map::SourceMap;
 use rustc_span::{Loc, Span, DUMMY_SP};
 use std::backtrace::{Backtrace, BacktraceStatus};
 use std::borrow::Cow;
+use std::cell::Cell;
 use std::error::Report;
 use std::fmt;
 use std::hash::Hash;
@@ -98,9 +99,9 @@ rustc_fluent_macro::fluent_messages! { "../messages.ftl" }
 
 // `PResult` is used a lot. Make sure it doesn't unintentionally get bigger.
 #[cfg(target_pointer_width = "64")]
-rustc_data_structures::static_assert_size!(PResult<'_, ()>, 16);
+rustc_data_structures::static_assert_size!(PResult<'_, ()>, 24);
 #[cfg(target_pointer_width = "64")]
-rustc_data_structures::static_assert_size!(PResult<'_, bool>, 16);
+rustc_data_structures::static_assert_size!(PResult<'_, bool>, 24);
 
 #[derive(Debug, PartialEq, Eq, Clone, Copy, Hash, Encodable, Decodable)]
 pub enum SuggestionStyle {
@@ -417,6 +418,9 @@ pub struct DiagCtxt {
 #[derive(Copy, Clone)]
 pub struct DiagCtxtHandle<'a> {
     dcx: &'a DiagCtxt,
+    /// Some contexts create `DiagCtxtHandle` with this field set, and thus all
+    /// errors emitted with it will automatically taint when emitting errors.
+    tainted_with_errors: Option<&'a Cell<Option<ErrorGuaranteed>>>,
 }
 
 impl<'a> std::ops::Deref for DiagCtxtHandle<'a> {
@@ -752,7 +756,17 @@ impl DiagCtxt {
     }
 
     pub fn handle<'a>(&'a self) -> DiagCtxtHandle<'a> {
-        DiagCtxtHandle { dcx: self }
+        DiagCtxtHandle { dcx: self, tainted_with_errors: None }
+    }
+
+    /// Link this to a taintable context so that emitting errors will automatically set
+    /// the `Option<ErrorGuaranteed>` instead of having to do that manually at every error
+    /// emission site.
+    pub fn taintable_handle<'a>(
+        &'a self,
+        tainted_with_errors: &'a Cell<Option<ErrorGuaranteed>>,
+    ) -> DiagCtxtHandle<'a> {
+        DiagCtxtHandle { dcx: self, tainted_with_errors: Some(tainted_with_errors) }
     }
 }
 
@@ -795,7 +809,9 @@ impl<'a> DiagCtxtHandle<'a> {
             // can be used to create a backtrace at the stashing site insted of whenever the
             // diagnostic context is dropped and thus delayed bugs are emitted.
             Error => Some(self.span_delayed_bug(span, format!("stashing {key:?}"))),
-            DelayedBug => return self.inner.borrow_mut().emit_diagnostic(diag),
+            DelayedBug => {
+                return self.inner.borrow_mut().emit_diagnostic(diag, self.tainted_with_errors);
+            }
             ForceWarning(_) | Warning | Note | OnceNote | Help | OnceHelp | FailureNote | Allow
             | Expect(_) => None,
         };
@@ -947,16 +963,19 @@ impl<'a> DiagCtxtHandle<'a> {
             (0, _) => {
                 // Use `ForceWarning` rather than `Warning` to guarantee emission, e.g. with a
                 // configuration like `--cap-lints allow --force-warn bare_trait_objects`.
-                inner.emit_diagnostic(DiagInner::new(
-                    ForceWarning(None),
-                    DiagMessage::Str(warnings),
-                ));
+                inner.emit_diagnostic(
+                    DiagInner::new(ForceWarning(None), DiagMessage::Str(warnings)),
+                    None,
+                );
             }
             (_, 0) => {
-                inner.emit_diagnostic(DiagInner::new(Error, errors));
+                inner.emit_diagnostic(DiagInner::new(Error, errors), self.tainted_with_errors);
             }
             (_, _) => {
-                inner.emit_diagnostic(DiagInner::new(Error, format!("{errors}; {warnings}")));
+                inner.emit_diagnostic(
+                    DiagInner::new(Error, format!("{errors}; {warnings}")),
+                    self.tainted_with_errors,
+                );
             }
         }
 
@@ -987,14 +1006,14 @@ impl<'a> DiagCtxtHandle<'a> {
                         "For more information about an error, try `rustc --explain {}`.",
                         &error_codes[0]
                     );
-                    inner.emit_diagnostic(DiagInner::new(FailureNote, msg1));
-                    inner.emit_diagnostic(DiagInner::new(FailureNote, msg2));
+                    inner.emit_diagnostic(DiagInner::new(FailureNote, msg1), None);
+                    inner.emit_diagnostic(DiagInner::new(FailureNote, msg2), None);
                 } else {
                     let msg = format!(
                         "For more information about this error, try `rustc --explain {}`.",
                         &error_codes[0]
                     );
-                    inner.emit_diagnostic(DiagInner::new(FailureNote, msg));
+                    inner.emit_diagnostic(DiagInner::new(FailureNote, msg), None);
                 }
             }
         }
@@ -1020,7 +1039,7 @@ impl<'a> DiagCtxtHandle<'a> {
     }
 
     pub fn emit_diagnostic(&self, diagnostic: DiagInner) -> Option<ErrorGuaranteed> {
-        self.inner.borrow_mut().emit_diagnostic(diagnostic)
+        self.inner.borrow_mut().emit_diagnostic(diagnostic, self.tainted_with_errors)
     }
 
     pub fn emit_artifact_notification(&self, path: &Path, artifact_type: &str) {
@@ -1080,7 +1099,7 @@ impl<'a> DiagCtxtHandle<'a> {
                 // Here the diagnostic is given back to `emit_diagnostic` where it was first
                 // intercepted. Now it should be processed as usual, since the unstable expectation
                 // id is now stable.
-                inner.emit_diagnostic(diag);
+                inner.emit_diagnostic(diag, self.tainted_with_errors);
             }
         }
 
@@ -1430,13 +1449,17 @@ impl DiagCtxtInner {
                     continue;
                 }
             }
-            guar = guar.or(self.emit_diagnostic(diag));
+            guar = guar.or(self.emit_diagnostic(diag, None));
         }
         guar
     }
 
     // Return value is only `Some` if the level is `Error` or `DelayedBug`.
-    fn emit_diagnostic(&mut self, mut diagnostic: DiagInner) -> Option<ErrorGuaranteed> {
+    fn emit_diagnostic(
+        &mut self,
+        mut diagnostic: DiagInner,
+        taint: Option<&Cell<Option<ErrorGuaranteed>>>,
+    ) -> Option<ErrorGuaranteed> {
         match diagnostic.level {
             Expect(expect_id) | ForceWarning(Some(expect_id)) => {
                 // The `LintExpectationId` can be stable or unstable depending on when it was
@@ -1609,6 +1632,9 @@ impl DiagCtxtInner {
                 if is_lint {
                     self.lint_err_guars.push(guar);
                 } else {
+                    if let Some(taint) = taint {
+                        taint.set(Some(guar));
+                    }
                     self.err_guars.push(guar);
                 }
                 self.panic_if_treat_err_as_bug();
@@ -1718,8 +1744,8 @@ impl DiagCtxtInner {
         // `-Ztreat-err-as-bug`, which we don't want.
         let note1 = "no errors encountered even though delayed bugs were created";
         let note2 = "those delayed bugs will now be shown as internal compiler errors";
-        self.emit_diagnostic(DiagInner::new(Note, note1));
-        self.emit_diagnostic(DiagInner::new(Note, note2));
+        self.emit_diagnostic(DiagInner::new(Note, note1), None);
+        self.emit_diagnostic(DiagInner::new(Note, note2), None);
 
         for bug in bugs {
             if let Some(out) = &mut out {
@@ -1752,7 +1778,7 @@ impl DiagCtxtInner {
             }
             bug.level = Bug;
 
-            self.emit_diagnostic(bug);
+            self.emit_diagnostic(bug, None);
         }
 
         // Panic with `DelayedBugPanic` to avoid "unexpected panic" messages.
diff --git a/compiler/rustc_hir_typeck/src/cast.rs b/compiler/rustc_hir_typeck/src/cast.rs
index 92f2d3254bb..cb1a412d17e 100644
--- a/compiler/rustc_hir_typeck/src/cast.rs
+++ b/compiler/rustc_hir_typeck/src/cast.rs
@@ -319,7 +319,7 @@ impl<'a, 'tcx> CastCheck<'tcx> {
                 } else {
                     errors::CannotCastToBoolHelp::Unsupported(self.span)
                 };
-                fcx.tcx.dcx().emit_err(errors::CannotCastToBool { span: self.span, expr_ty, help });
+                fcx.dcx().emit_err(errors::CannotCastToBool { span: self.span, expr_ty, help });
             }
             CastError::CastToChar => {
                 let mut err = type_error_struct!(
diff --git a/compiler/rustc_hir_typeck/src/coercion.rs b/compiler/rustc_hir_typeck/src/coercion.rs
index 0551b9bc1f0..f72e8a4afde 100644
--- a/compiler/rustc_hir_typeck/src/coercion.rs
+++ b/compiler/rustc_hir_typeck/src/coercion.rs
@@ -1797,16 +1797,16 @@ impl<'tcx, 'exprs, E: AsCoercionSite> CoerceMany<'tcx, 'exprs, E> {
         err.subdiagnostic(SuggestBoxingForReturnImplTrait::BoxReturnExpr { starts, ends });
     }
 
-    fn report_return_mismatched_types<'a>(
+    fn report_return_mismatched_types<'infcx>(
         &self,
         cause: &ObligationCause<'tcx>,
         expected: Ty<'tcx>,
         found: Ty<'tcx>,
         ty_err: TypeError<'tcx>,
-        fcx: &FnCtxt<'a, 'tcx>,
+        fcx: &'infcx FnCtxt<'_, 'tcx>,
         block_or_return_id: hir::HirId,
         expression: Option<&'tcx hir::Expr<'tcx>>,
-    ) -> Diag<'a> {
+    ) -> Diag<'infcx> {
         let mut err = fcx.err_ctxt().report_mismatched_types(cause, expected, found, ty_err);
 
         let due_to_block = matches!(fcx.tcx.hir_node(block_or_return_id), hir::Node::Block(..));
diff --git a/compiler/rustc_hir_typeck/src/demand.rs b/compiler/rustc_hir_typeck/src/demand.rs
index f9720c9c307..ad9c1e28211 100644
--- a/compiler/rustc_hir_typeck/src/demand.rs
+++ b/compiler/rustc_hir_typeck/src/demand.rs
@@ -172,21 +172,21 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     }
 
     pub fn demand_suptype_diag(
-        &self,
+        &'a self,
         sp: Span,
         expected: Ty<'tcx>,
         actual: Ty<'tcx>,
-    ) -> Result<(), Diag<'tcx>> {
+    ) -> Result<(), Diag<'a>> {
         self.demand_suptype_with_origin(&self.misc(sp), expected, actual)
     }
 
     #[instrument(skip(self), level = "debug")]
     pub fn demand_suptype_with_origin(
-        &self,
+        &'a self,
         cause: &ObligationCause<'tcx>,
         expected: Ty<'tcx>,
         actual: Ty<'tcx>,
-    ) -> Result<(), Diag<'tcx>> {
+    ) -> Result<(), Diag<'a>> {
         self.at(cause, self.param_env)
             .sup(DefineOpaqueTypes::Yes, expected, actual)
             .map(|infer_ok| self.register_infer_ok_obligations(infer_ok))
@@ -200,20 +200,20 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     }
 
     pub fn demand_eqtype_diag(
-        &self,
+        &'a self,
         sp: Span,
         expected: Ty<'tcx>,
         actual: Ty<'tcx>,
-    ) -> Result<(), Diag<'tcx>> {
+    ) -> Result<(), Diag<'a>> {
         self.demand_eqtype_with_origin(&self.misc(sp), expected, actual)
     }
 
     pub fn demand_eqtype_with_origin(
-        &self,
+        &'a self,
         cause: &ObligationCause<'tcx>,
         expected: Ty<'tcx>,
         actual: Ty<'tcx>,
-    ) -> Result<(), Diag<'tcx>> {
+    ) -> Result<(), Diag<'a>> {
         self.at(cause, self.param_env)
             .eq(DefineOpaqueTypes::Yes, expected, actual)
             .map(|infer_ok| self.register_infer_ok_obligations(infer_ok))
@@ -247,13 +247,13 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     /// will be permitted if the diverges flag is currently "always".
     #[instrument(level = "debug", skip(self, expr, expected_ty_expr, allow_two_phase))]
     pub fn demand_coerce_diag(
-        &self,
+        &'a self,
         mut expr: &'tcx hir::Expr<'tcx>,
         checked_ty: Ty<'tcx>,
         expected: Ty<'tcx>,
         mut expected_ty_expr: Option<&'tcx hir::Expr<'tcx>>,
         allow_two_phase: AllowTwoPhase,
-    ) -> Result<Ty<'tcx>, Diag<'tcx>> {
+    ) -> Result<Ty<'tcx>, Diag<'a>> {
         let expected = self.resolve_vars_with_obligations(expected);
 
         let e = match self.coerce(expr, checked_ty, expected, allow_two_phase, None) {
diff --git a/compiler/rustc_hir_typeck/src/expr.rs b/compiler/rustc_hir_typeck/src/expr.rs
index f4e1e461953..2fbc8a3f146 100644
--- a/compiler/rustc_hir_typeck/src/expr.rs
+++ b/compiler/rustc_hir_typeck/src/expr.rs
@@ -638,7 +638,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 // Set expectation to error in that case and set tainted
                 // by error (#114529)
                 let coerce_to = opt_coerce_to.unwrap_or_else(|| {
-                    let guar = tcx.dcx().span_delayed_bug(
+                    let guar = self.dcx().span_delayed_bug(
                         expr.span,
                         "illegal break with value found but no error reported",
                     );
@@ -1716,7 +1716,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             } else {
                 error_happened = true;
                 let guar = if let Some(prev_span) = seen_fields.get(&ident) {
-                    tcx.dcx().emit_err(FieldMultiplySpecifiedInInitializer {
+                    self.dcx().emit_err(FieldMultiplySpecifiedInInitializer {
                         span: field.ident.span,
                         prev_span: *prev_span,
                         ident,
@@ -1757,7 +1757,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         if adt_kind == AdtKind::Union {
             if hir_fields.len() != 1 {
                 struct_span_code_err!(
-                    tcx.dcx(),
+                    self.dcx(),
                     span,
                     E0784,
                     "union expressions should have exactly one field",
diff --git a/compiler/rustc_hir_typeck/src/expr_use_visitor.rs b/compiler/rustc_hir_typeck/src/expr_use_visitor.rs
index 0ba4bd090f5..9a353bfe49d 100644
--- a/compiler/rustc_hir_typeck/src/expr_use_visitor.rs
+++ b/compiler/rustc_hir_typeck/src/expr_use_visitor.rs
@@ -170,7 +170,7 @@ impl<'tcx> TypeInformationCtxt<'tcx> for &FnCtxt<'_, 'tcx> {
     }
 
     fn report_error(&self, span: Span, msg: impl ToString) -> Self::Error {
-        self.tcx.dcx().span_delayed_bug(span, msg.to_string())
+        self.dcx().span_delayed_bug(span, msg.to_string())
     }
 
     fn error_reported_in_ty(&self, ty: Ty<'tcx>) -> Result<(), Self::Error> {
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs
index f6e21262b6a..5450243417f 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs
@@ -1182,7 +1182,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     name: self.tcx.item_name(def.did()).to_ident_string(),
                 });
                 if ty.raw.has_param() {
-                    let guar = self.tcx.dcx().emit_err(errors::SelfCtorFromOuterItem {
+                    let guar = self.dcx().emit_err(errors::SelfCtorFromOuterItem {
                         span: path_span,
                         impl_span: tcx.def_span(impl_def_id),
                         sugg,
@@ -1207,7 +1207,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     // Check the visibility of the ctor.
                     let vis = tcx.visibility(ctor_def_id);
                     if !vis.is_accessible_from(tcx.parent_module(hir_id).to_def_id(), tcx) {
-                        tcx.dcx()
+                        self.dcx()
                             .emit_err(CtorIsPrivate { span, def: tcx.def_path_str(adt_def.did()) });
                     }
                     let new_res = Res::Def(DefKind::Ctor(CtorOf::Struct, ctor_kind), ctor_def_id);
@@ -1216,7 +1216,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     (new_res, Some(user_args.args))
                 }
                 _ => {
-                    let mut err = tcx.dcx().struct_span_err(
+                    let mut err = self.dcx().struct_span_err(
                         span,
                         "the `Self` constructor can only be used with tuple or unit structs",
                     );
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs
index 1138642c56d..430e12ff7b8 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs
@@ -238,7 +238,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     // Otherwise, there's a mismatch, so clear out what we're expecting, and set
                     // our input types to err_args so we don't blow up the error messages
                     let guar = struct_span_code_err!(
-                        tcx.dcx(),
+                        self.dcx(),
                         call_span,
                         E0059,
                         "cannot use call notation; the first type parameter \
@@ -453,7 +453,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     .map(|vars| self.resolve_vars_if_possible(vars)),
             );
 
-            self.set_tainted_by_errors(self.report_arg_errors(
+            self.report_arg_errors(
                 compatibility_diagonal,
                 formal_and_expected_inputs,
                 provided_args,
@@ -462,7 +462,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 fn_def_id,
                 call_span,
                 call_expr,
-            ));
+            );
         }
     }
 
@@ -788,7 +788,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             format!("arguments to this {call_name} are incorrect"),
                         );
                     } else {
-                        err = tcx.dcx().struct_span_err(
+                        err = self.dcx().struct_span_err(
                             full_call_span,
                             format!(
                                 "{call_name} takes {}{} but {} {} supplied",
@@ -848,7 +848,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 span_bug!(error_span, "expected errors from argument matrix");
             } else {
                 let mut err =
-                    tcx.dcx().create_err(errors::ArgMismatchIndeterminate { span: error_span });
+                    self.dcx().create_err(errors::ArgMismatchIndeterminate { span: error_span });
                 suggest_confusable(&mut err);
                 return err.emit();
             }
@@ -953,14 +953,14 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         let mut err = if formal_and_expected_inputs.len() == provided_args.len() {
             struct_span_code_err!(
-                tcx.dcx(),
+                self.dcx(),
                 full_call_span,
                 E0308,
                 "arguments to this {} are incorrect",
                 call_name,
             )
         } else {
-            tcx.dcx()
+            self.dcx()
                 .struct_span_err(
                     full_call_span,
                     format!(
@@ -1424,7 +1424,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         expected_ty: Ty<'tcx>,
         provided_ty: Ty<'tcx>,
         arg: &hir::Expr<'tcx>,
-        err: &mut Diag<'tcx>,
+        err: &mut Diag<'_>,
     ) {
         if let ty::RawPtr(_, hir::Mutability::Mut) = expected_ty.kind()
             && let ty::RawPtr(_, hir::Mutability::Not) = provided_ty.kind()
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs
index ed3cbb0663e..da68da029b4 100644
--- a/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs
+++ b/compiler/rustc_hir_typeck/src/fn_ctxt/mod.rs
@@ -144,8 +144,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         }
     }
 
-    pub(crate) fn dcx(&self) -> DiagCtxtHandle<'tcx> {
-        self.infcx.dcx()
+    pub(crate) fn dcx(&self) -> DiagCtxtHandle<'a> {
+        self.root_ctxt.infcx.dcx()
     }
 
     pub fn cause(&self, span: Span, code: ObligationCauseCode<'tcx>) -> ObligationCause<'tcx> {
diff --git a/compiler/rustc_hir_typeck/src/intrinsicck.rs b/compiler/rustc_hir_typeck/src/intrinsicck.rs
index 5eafc60a04e..0389c06c312 100644
--- a/compiler/rustc_hir_typeck/src/intrinsicck.rs
+++ b/compiler/rustc_hir_typeck/src/intrinsicck.rs
@@ -52,7 +52,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             // Note: this path is currently not reached in any test, so any
             // example that triggers this would be worth minimizing and
             // converting into a test.
-            tcx.dcx().span_bug(span, "argument to transmute has inference variables");
+            self.dcx().span_bug(span, "argument to transmute has inference variables");
         }
         // Transmutes that are only changing lifetimes are always ok.
         if from == to {
@@ -76,7 +76,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             if let (&ty::FnDef(..), SizeSkeleton::Known(size_to, _)) = (from.kind(), sk_to)
                 && size_to == Pointer(dl.instruction_address_space).size(&tcx)
             {
-                struct_span_code_err!(tcx.dcx(), span, E0591, "can't transmute zero-sized type")
+                struct_span_code_err!(self.dcx(), span, E0591, "can't transmute zero-sized type")
                     .with_note(format!("source type: {from}"))
                     .with_note(format!("target type: {to}"))
                     .with_help("cast with `as` to a pointer instead")
@@ -116,7 +116,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         };
 
         let mut err = struct_span_code_err!(
-            tcx.dcx(),
+            self.dcx(),
             span,
             E0512,
             "cannot transmute between types of different sizes, \
diff --git a/compiler/rustc_hir_typeck/src/method/suggest.rs b/compiler/rustc_hir_typeck/src/method/suggest.rs
index a385bc70e35..e310730bf9e 100644
--- a/compiler/rustc_hir_typeck/src/method/suggest.rs
+++ b/compiler/rustc_hir_typeck/src/method/suggest.rs
@@ -705,7 +705,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let mut err = if is_write && let SelfSource::MethodCall(rcvr_expr) = source {
             self.suggest_missing_writer(rcvr_ty, rcvr_expr)
         } else {
-            let mut err = tcx.dcx().create_err(NoAssociatedItem {
+            let mut err = self.dcx().create_err(NoAssociatedItem {
                 span,
                 item_kind,
                 item_name,
@@ -1194,7 +1194,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         span: item_span,
                         ..
                     })) => {
-                        tcx.dcx().span_delayed_bug(
+                        self.dcx().span_delayed_bug(
                             *item_span,
                             "auto trait is invoked with no method error, but no error reported?",
                         );
@@ -2361,7 +2361,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     );
                     if pick.is_ok() {
                         let range_span = parent_expr.span.with_hi(expr.span.hi());
-                        return Err(tcx.dcx().emit_err(errors::MissingParenthesesInRange {
+                        return Err(self.dcx().emit_err(errors::MissingParenthesesInRange {
                             span,
                             ty_str: ty_str.to_string(),
                             method_name: item_name.as_str().to_string(),
@@ -2420,7 +2420,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             && let SelfSource::MethodCall(expr) = source
         {
             let mut err = struct_span_code_err!(
-                tcx.dcx(),
+                self.dcx(),
                 span,
                 E0689,
                 "can't call {} `{}` on ambiguous numeric type `{}`",
diff --git a/compiler/rustc_hir_typeck/src/pat.rs b/compiler/rustc_hir_typeck/src/pat.rs
index aaf3d3ec34d..f932a27e9a2 100644
--- a/compiler/rustc_hir_typeck/src/pat.rs
+++ b/compiler/rustc_hir_typeck/src/pat.rs
@@ -89,7 +89,7 @@ struct PatInfo<'tcx, 'a> {
     current_depth: u32,
 }
 
-impl<'tcx> FnCtxt<'_, 'tcx> {
+impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     fn pattern_cause(&self, ti: &TopInfo<'tcx>, cause_span: Span) -> ObligationCause<'tcx> {
         let code = ObligationCauseCode::Pattern {
             span: ti.span,
@@ -100,12 +100,12 @@ impl<'tcx> FnCtxt<'_, 'tcx> {
     }
 
     fn demand_eqtype_pat_diag(
-        &self,
+        &'a self,
         cause_span: Span,
         expected: Ty<'tcx>,
         actual: Ty<'tcx>,
         ti: &TopInfo<'tcx>,
-    ) -> Result<(), Diag<'tcx>> {
+    ) -> Result<(), Diag<'a>> {
         self.demand_eqtype_with_origin(&self.pattern_cause(ti, cause_span), expected, actual)
             .map_err(|mut diag| {
                 if let Some(expr) = ti.origin_expr {
@@ -698,7 +698,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             && let MutblCap::WeaklyNot(and_pat_span) = pat_info.max_ref_mutbl
         {
             let mut err = struct_span_code_err!(
-                self.tcx.dcx(),
+                self.dcx(),
                 ident.span,
                 E0596,
                 "cannot borrow as mutable inside an `&` pattern"
@@ -1010,7 +1010,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let (res, opt_ty, segments) = path_resolution;
         match res {
             Res::Err => {
-                let e = tcx.dcx().span_delayed_bug(qpath.span(), "`Res::Err` but no error emitted");
+                let e =
+                    self.dcx().span_delayed_bug(qpath.span(), "`Res::Err` but no error emitted");
                 self.set_tainted_by_errors(e);
                 return Ty::new_error(tcx, e);
             }
@@ -1191,7 +1192,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let (res, opt_ty, segments) =
             self.resolve_ty_and_res_fully_qualified_call(qpath, pat.hir_id, pat.span);
         if res == Res::Err {
-            let e = tcx.dcx().span_delayed_bug(pat.span, "`Res::Err` but no error emitted");
+            let e = self.dcx().span_delayed_bug(pat.span, "`Res::Err` but no error emitted");
             self.set_tainted_by_errors(e);
             on_error(e);
             return Ty::new_error(tcx, e);
@@ -1207,7 +1208,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         let variant = match res {
             Res::Err => {
-                tcx.dcx().span_bug(pat.span, "`Res::Err` but no error emitted");
+                self.dcx().span_bug(pat.span, "`Res::Err` but no error emitted");
             }
             Res::Def(DefKind::AssocConst | DefKind::AssocFn, _) => {
                 let e = report_unexpected_res(res);
@@ -1549,10 +1550,10 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         // Report an error if an incorrect number of fields was specified.
         if adt.is_union() {
             if fields.len() != 1 {
-                tcx.dcx().emit_err(errors::UnionPatMultipleFields { span: pat.span });
+                self.dcx().emit_err(errors::UnionPatMultipleFields { span: pat.span });
             }
             if has_rest_pat {
-                tcx.dcx().emit_err(errors::UnionPatDotDot { span: pat.span });
+                self.dcx().emit_err(errors::UnionPatDotDot { span: pat.span });
             }
         } else if !unmentioned_fields.is_empty() {
             let accessible_unmentioned_fields: Vec<_> = unmentioned_fields
@@ -1690,7 +1691,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         pat: &'tcx Pat<'tcx>,
         variant: &ty::VariantDef,
         args: ty::GenericArgsRef<'tcx>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'a> {
         let tcx = self.tcx;
         let (field_names, t, plural) = if let [field] = inexistent_fields {
             (format!("a field named `{}`", field.ident), "this", "")
@@ -1710,7 +1711,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         };
         let spans = inexistent_fields.iter().map(|field| field.ident.span).collect::<Vec<_>>();
         let mut err = struct_span_code_err!(
-            tcx.dcx(),
+            self.dcx(),
             spans,
             E0026,
             "{} `{}` does not have {}",
@@ -1881,7 +1882,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         &self,
         pat: &Pat<'_>,
         fields: &'tcx [hir::PatField<'tcx>],
-    ) -> Diag<'tcx> {
+    ) -> Diag<'a> {
         let mut err = self
             .dcx()
             .struct_span_err(pat.span, "pattern requires `..` due to inaccessible fields");
@@ -1973,7 +1974,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         unmentioned_fields: &[(&ty::FieldDef, Ident)],
         have_inaccessible_fields: bool,
         fields: &'tcx [hir::PatField<'tcx>],
-    ) -> Diag<'tcx> {
+    ) -> Diag<'a> {
         let inaccessible = if have_inaccessible_fields { " and inaccessible fields" } else { "" };
         let field_names = if let [(_, field)] = unmentioned_fields {
             format!("field `{field}`{inaccessible}")
diff --git a/compiler/rustc_infer/src/infer/error_reporting/mod.rs b/compiler/rustc_infer/src/infer/error_reporting/mod.rs
index 227691d0994..a8fd3ca8c59 100644
--- a/compiler/rustc_infer/src/infer/error_reporting/mod.rs
+++ b/compiler/rustc_infer/src/infer/error_reporting/mod.rs
@@ -139,7 +139,7 @@ pub struct TypeErrCtxt<'a, 'tcx> {
 }
 
 impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
-    pub fn dcx(&self) -> DiagCtxtHandle<'tcx> {
+    pub fn dcx(&self) -> DiagCtxtHandle<'a> {
         self.infcx.dcx()
     }
 
@@ -305,16 +305,17 @@ fn label_msg_span(
     }
 }
 
-#[instrument(level = "trace", skip(tcx))]
-pub fn unexpected_hidden_region_diagnostic<'tcx>(
-    tcx: TyCtxt<'tcx>,
+#[instrument(level = "trace", skip(infcx))]
+pub fn unexpected_hidden_region_diagnostic<'a, 'tcx>(
+    infcx: &'a InferCtxt<'tcx>,
     generic_param_scope: LocalDefId,
     span: Span,
     hidden_ty: Ty<'tcx>,
     hidden_region: ty::Region<'tcx>,
     opaque_ty_key: ty::OpaqueTypeKey<'tcx>,
-) -> Diag<'tcx> {
-    let mut err = tcx.dcx().create_err(errors::OpaqueCapturesLifetime {
+) -> Diag<'a> {
+    let tcx = infcx.tcx;
+    let mut err = infcx.dcx().create_err(errors::OpaqueCapturesLifetime {
         span,
         opaque_ty: Ty::new_opaque(tcx, opaque_ty_key.def_id.to_def_id(), opaque_ty_key.args),
         opaque_ty_span: tcx.def_span(opaque_ty_key.def_id),
@@ -436,7 +437,7 @@ impl<'tcx> InferCtxt<'tcx> {
     }
 }
 
-impl<'tcx> TypeErrCtxt<'_, 'tcx> {
+impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
     pub fn report_region_errors(
         &self,
         generic_param_scope: LocalDefId,
@@ -2206,7 +2207,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         &self,
         trace: TypeTrace<'tcx>,
         terr: TypeError<'tcx>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'a> {
         debug!("report_and_explain_type_error(trace={:?}, terr={:?})", trace, terr);
 
         let span = trace.cause.span();
@@ -2215,7 +2216,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
             span,
             self.type_error_additional_suggestions(&trace, terr),
         );
-        let mut diag = self.tcx.dcx().create_err(failure_code);
+        let mut diag = self.dcx().create_err(failure_code);
         self.note_type_err(&mut diag, &trace.cause, None, Some(trace.values), terr, false, false);
         diag
     }
@@ -2357,14 +2358,14 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         origin: Option<SubregionOrigin<'tcx>>,
         bound_kind: GenericKind<'tcx>,
         sub: Region<'tcx>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'a> {
         if let Some(SubregionOrigin::CompareImplItemObligation {
             span,
             impl_item_def_id,
             trait_item_def_id,
         }) = origin
         {
-            return self.report_extra_impl_obligation(
+            return self.infcx.report_extra_impl_obligation(
                 span,
                 impl_item_def_id,
                 trait_item_def_id,
@@ -2790,7 +2791,7 @@ impl<'tcx> TypeRelation<TyCtxt<'tcx>> for SameTypeModuloInfer<'_, 'tcx> {
 }
 
 impl<'tcx> InferCtxt<'tcx> {
-    fn report_inference_failure(&self, var_origin: RegionVariableOrigin) -> Diag<'tcx> {
+    fn report_inference_failure(&self, var_origin: RegionVariableOrigin) -> Diag<'_> {
         let br_string = |br: ty::BoundRegionKind| {
             let mut s = match br {
                 ty::BrNamed(_, name) => name.to_string(),
@@ -2829,7 +2830,7 @@ impl<'tcx> InferCtxt<'tcx> {
         };
 
         struct_span_code_err!(
-            self.tcx.dcx(),
+            self.dcx(),
             var_origin.span(),
             E0495,
             "cannot infer an appropriate lifetime{} due to conflicting requirements",
diff --git a/compiler/rustc_infer/src/infer/error_reporting/need_type_info.rs b/compiler/rustc_infer/src/infer/error_reporting/need_type_info.rs
index d7349abc44c..084aebc296f 100644
--- a/compiler/rustc_infer/src/infer/error_reporting/need_type_info.rs
+++ b/compiler/rustc_infer/src/infer/error_reporting/need_type_info.rs
@@ -391,7 +391,7 @@ impl<'tcx> InferCtxt<'tcx> {
         span: Span,
         arg_data: InferenceDiagnosticsData,
         error_code: TypeAnnotationNeeded,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'_> {
         let source_kind = "other";
         let source_name = "";
         let failure_span = None;
@@ -436,7 +436,7 @@ impl<'tcx> InferCtxt<'tcx> {
     }
 }
 
-impl<'tcx> TypeErrCtxt<'_, 'tcx> {
+impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
     #[instrument(level = "debug", skip(self, error_code))]
     pub fn emit_inference_failure_err(
         &self,
@@ -445,7 +445,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         arg: GenericArg<'tcx>,
         error_code: TypeAnnotationNeeded,
         should_label_span: bool,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'a> {
         let arg = self.resolve_vars_if_possible(arg);
         let arg_data = self.extract_inference_diagnostics_data(arg, None);
 
@@ -453,7 +453,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
             // If we don't have any typeck results we're outside
             // of a body, so we won't be able to get better info
             // here.
-            return self.bad_inference_failure_err(failure_span, arg_data, error_code);
+            return self.infcx.bad_inference_failure_err(failure_span, arg_data, error_code);
         };
 
         let mut local_visitor = FindInferSourceVisitor::new(self, typeck_results, arg);
@@ -465,7 +465,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         }
 
         let Some(InferSource { span, kind }) = local_visitor.infer_source else {
-            return self.bad_inference_failure_err(failure_span, arg_data, error_code);
+            return self.infcx.bad_inference_failure_err(failure_span, arg_data, error_code);
         };
 
         let (source_kind, name, path) = kind.ty_localized_msg(self);
diff --git a/compiler/rustc_infer/src/infer/error_reporting/note.rs b/compiler/rustc_infer/src/infer/error_reporting/note.rs
index 8fd19563c30..d1fc9c9f140 100644
--- a/compiler/rustc_infer/src/infer/error_reporting/note.rs
+++ b/compiler/rustc_infer/src/infer/error_reporting/note.rs
@@ -14,7 +14,7 @@ use rustc_span::symbol::kw;
 
 use super::ObligationCauseAsDiagArg;
 
-impl<'tcx> TypeErrCtxt<'_, 'tcx> {
+impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
     pub(super) fn note_region_origin(&self, err: &mut Diag<'_>, origin: &SubregionOrigin<'tcx>) {
         match *origin {
             infer::Subtype(ref trace) => RegionOriginNote::WithRequirement {
@@ -79,7 +79,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         origin: SubregionOrigin<'tcx>,
         sub: Region<'tcx>,
         sup: Region<'tcx>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'a> {
         let mut err = match origin {
             infer::Subtype(box trace) => {
                 let terr = TypeError::RegionsDoesNotOutlive(sup, sub);
@@ -245,7 +245,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                 })
             }
             infer::CompareImplItemObligation { span, impl_item_def_id, trait_item_def_id } => {
-                let mut err = self.report_extra_impl_obligation(
+                let mut err = self.infcx.report_extra_impl_obligation(
                     span,
                     impl_item_def_id,
                     trait_item_def_id,
@@ -378,7 +378,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         placeholder_origin: SubregionOrigin<'tcx>,
         sub: Region<'tcx>,
         sup: Region<'tcx>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'a> {
         // I can't think how to do better than this right now. -nikomatsakis
         debug!(?placeholder_origin, ?sub, ?sup, "report_placeholder_failure");
         match placeholder_origin {
diff --git a/compiler/rustc_infer/src/infer/mod.rs b/compiler/rustc_infer/src/infer/mod.rs
index a3cf588da1c..ff593d7ffb7 100644
--- a/compiler/rustc_infer/src/infer/mod.rs
+++ b/compiler/rustc_infer/src/infer/mod.rs
@@ -684,8 +684,8 @@ impl<'tcx> InferOk<'tcx, ()> {
 }
 
 impl<'tcx> InferCtxt<'tcx> {
-    pub fn dcx(&self) -> DiagCtxtHandle<'tcx> {
-        self.tcx.dcx()
+    pub fn dcx(&self) -> DiagCtxtHandle<'_> {
+        self.tcx.dcx().taintable_handle(&self.tainted_by_errors)
     }
 
     pub fn defining_opaque_types(&self) -> &'tcx ty::List<LocalDefId> {
@@ -1089,19 +1089,7 @@ impl<'tcx> InferCtxt<'tcx> {
     /// inference variables, regionck errors).
     #[must_use = "this method does not have any side effects"]
     pub fn tainted_by_errors(&self) -> Option<ErrorGuaranteed> {
-        if let Some(guar) = self.tainted_by_errors.get() {
-            Some(guar)
-        } else if self.dcx().err_count_excluding_lint_errs() > self.err_count_on_creation {
-            // Errors reported since this infcx was made. Lint errors are
-            // excluded to avoid some being swallowed in the presence of
-            // non-lint errors. (It's arguable whether or not this exclusion is
-            // important.)
-            let guar = self.dcx().has_errors().unwrap();
-            self.set_tainted_by_errors(guar);
-            Some(guar)
-        } else {
-            None
-        }
+        self.tainted_by_errors.get()
     }
 
     /// Set the "tainted by errors" flag to true. We call this when we
@@ -1328,8 +1316,7 @@ impl<'tcx> InferCtxt<'tcx> {
                     bug!("`{value:?}` is not fully resolved");
                 }
                 if value.has_infer_regions() {
-                    let guar =
-                        self.tcx.dcx().delayed_bug(format!("`{value:?}` is not fully resolved"));
+                    let guar = self.dcx().delayed_bug(format!("`{value:?}` is not fully resolved"));
                     Ok(self.tcx.fold_regions(value, |re, _| {
                         if re.is_var() { ty::Region::new_error(self.tcx, guar) } else { re }
                     }))
@@ -1607,7 +1594,7 @@ impl<'tcx> InferCtxt<'tcx> {
     }
 }
 
-impl<'tcx> TypeErrCtxt<'_, 'tcx> {
+impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
     // [Note-Type-error-reporting]
     // An invariant is that anytime the expected or actual type is Error (the special
     // error type, meaning that an error occurred when typechecking this expression),
@@ -1623,9 +1610,9 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         sp: Span,
         mk_diag: M,
         actual_ty: Ty<'tcx>,
-    ) -> Diag<'tcx>
+    ) -> Diag<'a>
     where
-        M: FnOnce(String) -> Diag<'tcx>,
+        M: FnOnce(String) -> Diag<'a>,
     {
         let actual_ty = self.resolve_vars_if_possible(actual_ty);
         debug!("type_error_struct_with_diag({:?}, {:?})", sp, actual_ty);
@@ -1646,7 +1633,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         expected: Ty<'tcx>,
         actual: Ty<'tcx>,
         err: TypeError<'tcx>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'a> {
         self.report_and_explain_type_error(TypeTrace::types(cause, true, expected, actual), err)
     }
 
@@ -1656,7 +1643,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         expected: ty::Const<'tcx>,
         actual: ty::Const<'tcx>,
         err: TypeError<'tcx>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'a> {
         self.report_and_explain_type_error(TypeTrace::consts(cause, true, expected, actual), err)
     }
 }
diff --git a/compiler/rustc_infer/src/infer/opaque_types/mod.rs b/compiler/rustc_infer/src/infer/opaque_types/mod.rs
index b8dd501a721..7c764cccc47 100644
--- a/compiler/rustc_infer/src/infer/opaque_types/mod.rs
+++ b/compiler/rustc_infer/src/infer/opaque_types/mod.rs
@@ -156,7 +156,7 @@ impl<'tcx> InferCtxt<'tcx> {
                     if self.can_define_opaque_ty(b_def_id)
                         && self.tcx.is_type_alias_impl_trait(b_def_id)
                     {
-                        self.tcx.dcx().emit_err(OpaqueHiddenTypeDiag {
+                        self.dcx().emit_err(OpaqueHiddenTypeDiag {
                             span,
                             hidden_type: self.tcx.def_span(b_def_id),
                             opaque_type: self.tcx.def_span(def_id),
diff --git a/compiler/rustc_infer/src/traits/error_reporting/mod.rs b/compiler/rustc_infer/src/traits/error_reporting/mod.rs
index 890e25368bc..7730fe29e09 100644
--- a/compiler/rustc_infer/src/traits/error_reporting/mod.rs
+++ b/compiler/rustc_infer/src/traits/error_reporting/mod.rs
@@ -12,15 +12,15 @@ use std::fmt;
 use std::iter;
 
 impl<'tcx> InferCtxt<'tcx> {
-    pub fn report_extra_impl_obligation(
-        &self,
+    pub fn report_extra_impl_obligation<'a>(
+        &'a self,
         error_span: Span,
         impl_item_def_id: LocalDefId,
         trait_item_def_id: DefId,
         requirement: &dyn fmt::Display,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'a> {
         let mut err = struct_span_code_err!(
-            self.tcx.dcx(),
+            self.dcx(),
             error_span,
             E0276,
             "impl has stricter requirements than trait"
diff --git a/compiler/rustc_mir_dataflow/src/impls/initialized.rs b/compiler/rustc_mir_dataflow/src/impls/initialized.rs
index f0b79dab0c9..ffcf630b653 100644
--- a/compiler/rustc_mir_dataflow/src/impls/initialized.rs
+++ b/compiler/rustc_mir_dataflow/src/impls/initialized.rs
@@ -50,15 +50,19 @@ use crate::{lattice, AnalysisDomain, GenKill, GenKillAnalysis, MaybeReachable};
 /// Similarly, at a given `drop` statement, the set-intersection
 /// between this data and `MaybeUninitializedPlaces` yields the set of
 /// places that would require a dynamic drop-flag at that statement.
-pub struct MaybeInitializedPlaces<'a, 'tcx> {
+pub struct MaybeInitializedPlaces<'a, 'mir, 'tcx> {
     tcx: TyCtxt<'tcx>,
-    body: &'a Body<'tcx>,
+    body: &'mir Body<'tcx>,
     mdpe: &'a MoveDataParamEnv<'tcx>,
     skip_unreachable_unwind: bool,
 }
 
-impl<'a, 'tcx> MaybeInitializedPlaces<'a, 'tcx> {
-    pub fn new(tcx: TyCtxt<'tcx>, body: &'a Body<'tcx>, mdpe: &'a MoveDataParamEnv<'tcx>) -> Self {
+impl<'a, 'mir, 'tcx> MaybeInitializedPlaces<'a, 'mir, 'tcx> {
+    pub fn new(
+        tcx: TyCtxt<'tcx>,
+        body: &'mir Body<'tcx>,
+        mdpe: &'a MoveDataParamEnv<'tcx>,
+    ) -> Self {
         MaybeInitializedPlaces { tcx, body, mdpe, skip_unreachable_unwind: false }
     }
 
@@ -84,7 +88,7 @@ impl<'a, 'tcx> MaybeInitializedPlaces<'a, 'tcx> {
     }
 }
 
-impl<'a, 'tcx> HasMoveData<'tcx> for MaybeInitializedPlaces<'a, 'tcx> {
+impl<'a, 'mir, 'tcx> HasMoveData<'tcx> for MaybeInitializedPlaces<'a, 'mir, 'tcx> {
     fn move_data(&self) -> &MoveData<'tcx> {
         &self.mdpe.move_data
     }
@@ -125,17 +129,21 @@ impl<'a, 'tcx> HasMoveData<'tcx> for MaybeInitializedPlaces<'a, 'tcx> {
 /// Similarly, at a given `drop` statement, the set-intersection
 /// between this data and `MaybeInitializedPlaces` yields the set of
 /// places that would require a dynamic drop-flag at that statement.
-pub struct MaybeUninitializedPlaces<'a, 'tcx> {
+pub struct MaybeUninitializedPlaces<'a, 'mir, 'tcx> {
     tcx: TyCtxt<'tcx>,
-    body: &'a Body<'tcx>,
+    body: &'mir Body<'tcx>,
     mdpe: &'a MoveDataParamEnv<'tcx>,
 
     mark_inactive_variants_as_uninit: bool,
     skip_unreachable_unwind: BitSet<mir::BasicBlock>,
 }
 
-impl<'a, 'tcx> MaybeUninitializedPlaces<'a, 'tcx> {
-    pub fn new(tcx: TyCtxt<'tcx>, body: &'a Body<'tcx>, mdpe: &'a MoveDataParamEnv<'tcx>) -> Self {
+impl<'a, 'mir, 'tcx> MaybeUninitializedPlaces<'a, 'mir, 'tcx> {
+    pub fn new(
+        tcx: TyCtxt<'tcx>,
+        body: &'mir Body<'tcx>,
+        mdpe: &'a MoveDataParamEnv<'tcx>,
+    ) -> Self {
         MaybeUninitializedPlaces {
             tcx,
             body,
@@ -164,7 +172,7 @@ impl<'a, 'tcx> MaybeUninitializedPlaces<'a, 'tcx> {
     }
 }
 
-impl<'a, 'tcx> HasMoveData<'tcx> for MaybeUninitializedPlaces<'a, 'tcx> {
+impl<'a, 'tcx> HasMoveData<'tcx> for MaybeUninitializedPlaces<'a, '_, 'tcx> {
     fn move_data(&self) -> &MoveData<'tcx> {
         &self.mdpe.move_data
     }
@@ -250,24 +258,24 @@ impl<'a, 'tcx> HasMoveData<'tcx> for DefinitelyInitializedPlaces<'a, 'tcx> {
 ///     c = S;                                  // {a, b, c, d }
 /// }
 /// ```
-pub struct EverInitializedPlaces<'a, 'tcx> {
-    body: &'a Body<'tcx>,
+pub struct EverInitializedPlaces<'a, 'mir, 'tcx> {
+    body: &'mir Body<'tcx>,
     mdpe: &'a MoveDataParamEnv<'tcx>,
 }
 
-impl<'a, 'tcx> EverInitializedPlaces<'a, 'tcx> {
-    pub fn new(body: &'a Body<'tcx>, mdpe: &'a MoveDataParamEnv<'tcx>) -> Self {
+impl<'a, 'mir, 'tcx> EverInitializedPlaces<'a, 'mir, 'tcx> {
+    pub fn new(body: &'mir Body<'tcx>, mdpe: &'a MoveDataParamEnv<'tcx>) -> Self {
         EverInitializedPlaces { body, mdpe }
     }
 }
 
-impl<'a, 'tcx> HasMoveData<'tcx> for EverInitializedPlaces<'a, 'tcx> {
+impl<'a, 'tcx> HasMoveData<'tcx> for EverInitializedPlaces<'a, '_, 'tcx> {
     fn move_data(&self) -> &MoveData<'tcx> {
         &self.mdpe.move_data
     }
 }
 
-impl<'a, 'tcx> MaybeInitializedPlaces<'a, 'tcx> {
+impl<'a, 'mir, 'tcx> MaybeInitializedPlaces<'a, 'mir, 'tcx> {
     fn update_bits(
         trans: &mut impl GenKill<MovePathIndex>,
         path: MovePathIndex,
@@ -280,7 +288,7 @@ impl<'a, 'tcx> MaybeInitializedPlaces<'a, 'tcx> {
     }
 }
 
-impl<'a, 'tcx> MaybeUninitializedPlaces<'a, 'tcx> {
+impl<'a, 'tcx> MaybeUninitializedPlaces<'a, '_, 'tcx> {
     fn update_bits(
         trans: &mut impl GenKill<MovePathIndex>,
         path: MovePathIndex,
@@ -306,7 +314,7 @@ impl<'a, 'tcx> DefinitelyInitializedPlaces<'a, 'tcx> {
     }
 }
 
-impl<'tcx> AnalysisDomain<'tcx> for MaybeInitializedPlaces<'_, 'tcx> {
+impl<'tcx> AnalysisDomain<'tcx> for MaybeInitializedPlaces<'_, '_, 'tcx> {
     /// There can be many more `MovePathIndex` than there are locals in a MIR body.
     /// We use a chunked bitset to avoid paying too high a memory footprint.
     type Domain = MaybeReachable<ChunkedBitSet<MovePathIndex>>;
@@ -328,7 +336,7 @@ impl<'tcx> AnalysisDomain<'tcx> for MaybeInitializedPlaces<'_, 'tcx> {
     }
 }
 
-impl<'tcx> GenKillAnalysis<'tcx> for MaybeInitializedPlaces<'_, 'tcx> {
+impl<'tcx> GenKillAnalysis<'tcx> for MaybeInitializedPlaces<'_, '_, 'tcx> {
     type Idx = MovePathIndex;
 
     fn domain_size(&self, _: &Body<'tcx>) -> usize {
@@ -441,7 +449,7 @@ impl<'tcx> GenKillAnalysis<'tcx> for MaybeInitializedPlaces<'_, 'tcx> {
     }
 }
 
-impl<'tcx> AnalysisDomain<'tcx> for MaybeUninitializedPlaces<'_, 'tcx> {
+impl<'tcx> AnalysisDomain<'tcx> for MaybeUninitializedPlaces<'_, '_, 'tcx> {
     /// There can be many more `MovePathIndex` than there are locals in a MIR body.
     /// We use a chunked bitset to avoid paying too high a memory footprint.
     type Domain = ChunkedBitSet<MovePathIndex>;
@@ -465,7 +473,7 @@ impl<'tcx> AnalysisDomain<'tcx> for MaybeUninitializedPlaces<'_, 'tcx> {
     }
 }
 
-impl<'tcx> GenKillAnalysis<'tcx> for MaybeUninitializedPlaces<'_, 'tcx> {
+impl<'tcx> GenKillAnalysis<'tcx> for MaybeUninitializedPlaces<'_, '_, 'tcx> {
     type Idx = MovePathIndex;
 
     fn domain_size(&self, _: &Body<'tcx>) -> usize {
@@ -642,7 +650,7 @@ impl<'tcx> GenKillAnalysis<'tcx> for DefinitelyInitializedPlaces<'_, 'tcx> {
     }
 }
 
-impl<'tcx> AnalysisDomain<'tcx> for EverInitializedPlaces<'_, 'tcx> {
+impl<'tcx> AnalysisDomain<'tcx> for EverInitializedPlaces<'_, '_, 'tcx> {
     /// There can be many more `InitIndex` than there are locals in a MIR body.
     /// We use a chunked bitset to avoid paying too high a memory footprint.
     type Domain = ChunkedBitSet<InitIndex>;
@@ -661,7 +669,7 @@ impl<'tcx> AnalysisDomain<'tcx> for EverInitializedPlaces<'_, 'tcx> {
     }
 }
 
-impl<'tcx> GenKillAnalysis<'tcx> for EverInitializedPlaces<'_, 'tcx> {
+impl<'tcx> GenKillAnalysis<'tcx> for EverInitializedPlaces<'_, '_, 'tcx> {
     type Idx = InitIndex;
 
     fn domain_size(&self, _: &Body<'tcx>) -> usize {
diff --git a/compiler/rustc_mir_transform/src/elaborate_drops.rs b/compiler/rustc_mir_transform/src/elaborate_drops.rs
index 665b2260294..fbbb8c5e472 100644
--- a/compiler/rustc_mir_transform/src/elaborate_drops.rs
+++ b/compiler/rustc_mir_transform/src/elaborate_drops.rs
@@ -97,7 +97,7 @@ impl<'tcx> MirPass<'tcx> for ElaborateDrops {
 #[instrument(level = "trace", skip(body, flow_inits), ret)]
 fn compute_dead_unwinds<'mir, 'tcx>(
     body: &'mir Body<'tcx>,
-    flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'mir, 'tcx>>,
+    flow_inits: &mut ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'_, 'mir, 'tcx>>,
 ) -> BitSet<BasicBlock> {
     // We only need to do this pass once, because unwind edges can only
     // reach cleanup blocks, which can't have unwind edges themselves.
@@ -118,12 +118,12 @@ fn compute_dead_unwinds<'mir, 'tcx>(
     dead_unwinds
 }
 
-struct InitializationData<'mir, 'tcx> {
-    inits: ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'mir, 'tcx>>,
-    uninits: ResultsCursor<'mir, 'tcx, MaybeUninitializedPlaces<'mir, 'tcx>>,
+struct InitializationData<'a, 'mir, 'tcx> {
+    inits: ResultsCursor<'mir, 'tcx, MaybeInitializedPlaces<'a, 'mir, 'tcx>>,
+    uninits: ResultsCursor<'mir, 'tcx, MaybeUninitializedPlaces<'a, 'mir, 'tcx>>,
 }
 
-impl InitializationData<'_, '_> {
+impl InitializationData<'_, '_, '_> {
     fn seek_before(&mut self, loc: Location) {
         self.inits.seek_before_primary_effect(loc);
         self.uninits.seek_before_primary_effect(loc);
@@ -134,17 +134,17 @@ impl InitializationData<'_, '_> {
     }
 }
 
-struct Elaborator<'a, 'b, 'tcx> {
-    ctxt: &'a mut ElaborateDropsCtxt<'b, 'tcx>,
+struct Elaborator<'a, 'b, 'mir, 'tcx> {
+    ctxt: &'a mut ElaborateDropsCtxt<'b, 'mir, 'tcx>,
 }
 
-impl fmt::Debug for Elaborator<'_, '_, '_> {
+impl fmt::Debug for Elaborator<'_, '_, '_, '_> {
     fn fmt(&self, _f: &mut fmt::Formatter<'_>) -> fmt::Result {
         Ok(())
     }
 }
 
-impl<'a, 'tcx> DropElaborator<'a, 'tcx> for Elaborator<'a, '_, 'tcx> {
+impl<'a, 'tcx> DropElaborator<'a, 'tcx> for Elaborator<'a, '_, '_, 'tcx> {
     type Path = MovePathIndex;
 
     fn patch(&mut self) -> &mut MirPatch<'tcx> {
@@ -238,16 +238,16 @@ impl<'a, 'tcx> DropElaborator<'a, 'tcx> for Elaborator<'a, '_, 'tcx> {
     }
 }
 
-struct ElaborateDropsCtxt<'a, 'tcx> {
+struct ElaborateDropsCtxt<'a, 'mir, 'tcx> {
     tcx: TyCtxt<'tcx>,
-    body: &'a Body<'tcx>,
+    body: &'mir Body<'tcx>,
     env: &'a MoveDataParamEnv<'tcx>,
-    init_data: InitializationData<'a, 'tcx>,
+    init_data: InitializationData<'a, 'mir, 'tcx>,
     drop_flags: IndexVec<MovePathIndex, Option<Local>>,
     patch: MirPatch<'tcx>,
 }
 
-impl<'b, 'tcx> ElaborateDropsCtxt<'b, 'tcx> {
+impl<'b, 'mir, 'tcx> ElaborateDropsCtxt<'b, 'mir, 'tcx> {
     fn move_data(&self) -> &'b MoveData<'tcx> {
         &self.env.move_data
     }
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/infer_ctxt_ext.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/infer_ctxt_ext.rs
index 4b5b1d77b30..34da8e576ce 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/infer_ctxt_ext.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/infer_ctxt_ext.rs
@@ -88,7 +88,7 @@ impl<'tcx> InferCtxt<'tcx> {
         found_args: Vec<ArgKind>,
         is_closure: bool,
         closure_arg_span: Option<Span>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'_> {
         let kind = if is_closure { "closure" } else { "function" };
 
         let args_str = |arguments: &[ArgKind], other: &[ArgKind]| {
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
index 599a95f2300..ccf86dbb1d0 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/suggestions.rs
@@ -241,8 +241,8 @@ pub fn suggest_restriction<'tcx, G: EmissionGuarantee>(
     }
 }
 
-#[extension(pub trait TypeErrCtxtExt<'tcx>)]
-impl<'tcx> TypeErrCtxt<'_, 'tcx> {
+#[extension(pub trait TypeErrCtxtExt<'a, 'tcx>)]
+impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
     fn suggest_restricting_param_bound(
         &self,
         err: &mut Diag<'_>,
@@ -1845,7 +1845,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
 
     fn point_at_returns_when_relevant(
         &self,
-        err: &mut Diag<'tcx>,
+        err: &mut Diag<'_>,
         obligation: &PredicateObligation<'tcx>,
     ) {
         match obligation.cause.code().peel_derives() {
@@ -1884,7 +1884,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         cause: &ObligationCauseCode<'tcx>,
         found_node: Option<Node<'_>>,
         param_env: ty::ParamEnv<'tcx>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'a> {
         pub(crate) fn build_fn_sig_ty<'tcx>(
             infcx: &InferCtxt<'tcx>,
             trait_ref: ty::TraitRef<'tcx>,
@@ -2104,7 +2104,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
     fn note_conflicting_closure_bounds(
         &self,
         cause: &ObligationCauseCode<'tcx>,
-        err: &mut Diag<'tcx>,
+        err: &mut Diag<'_>,
     ) {
         // First, look for an `WhereClauseInExpr`, which means we can get
         // the uninstantiated predicate list of the called function. And check
diff --git a/compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs b/compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs
index d3096cf4b52..adf1076a7c9 100644
--- a/compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs
+++ b/compiler/rustc_trait_selection/src/traits/error_reporting/type_err_ctxt_ext.rs
@@ -82,8 +82,8 @@ pub fn suggest_new_overflow_limit<'tcx, G: EmissionGuarantee>(
     ));
 }
 
-#[extension(pub trait TypeErrCtxtExt<'tcx>)]
-impl<'tcx> TypeErrCtxt<'_, 'tcx> {
+#[extension(pub trait TypeErrCtxtExt<'a, 'tcx>)]
+impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
     fn report_fulfillment_errors(
         &self,
         mut errors: Vec<FulfillmentError<'tcx>>,
@@ -228,7 +228,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         cause: OverflowCause<'tcx>,
         span: Span,
         suggest_increasing_limit: bool,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'a> {
         fn with_short_path<'tcx, T>(tcx: TyCtxt<'tcx>, value: T) -> String
         where
             T: fmt::Display + Print<'tcx, FmtPrinter<'tcx, 'tcx>>,
@@ -1101,7 +1101,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                 && let ty::FnPtr(sig) = by_ref_captures.kind()
                 && !sig.skip_binder().output().is_unit()
             {
-                let mut err = self.tcx.dcx().create_err(AsyncClosureNotFn {
+                let mut err = self.dcx().create_err(AsyncClosureNotFn {
                     span: self.tcx.def_span(closure_def_id),
                     kind: expected_kind.as_str(),
                 });
@@ -1351,7 +1351,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         &self,
         ty: Ty<'tcx>,
         obligation: &PredicateObligation<'tcx>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'a> {
         let span = obligation.cause.span;
 
         let mut diag = match ty.kind() {
@@ -1445,8 +1445,8 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
     }
 }
 
-#[extension(pub(super) trait InferCtxtPrivExt<'tcx>)]
-impl<'tcx> TypeErrCtxt<'_, 'tcx> {
+#[extension(pub(super) trait InferCtxtPrivExt<'a, 'tcx>)]
+impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
     fn can_match_trait(
         &self,
         goal: ty::TraitPredicate<'tcx>,
@@ -2884,7 +2884,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
             self.suggest_unsized_bound_if_applicable(err, obligation);
             if let Some(span) = err.span.primary_span()
                 && let Some(mut diag) =
-                    self.tcx.dcx().steal_non_err(span, StashKey::AssociatedTypeSuggestion)
+                    self.dcx().steal_non_err(span, StashKey::AssociatedTypeSuggestion)
                 && let Ok(ref mut s1) = err.suggestions
                 && let Ok(ref mut s2) = diag.suggestions
             {
@@ -3379,7 +3379,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         found_kind: ty::ClosureKind,
         kind: ty::ClosureKind,
         trait_prefix: &'static str,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'a> {
         let closure_span = self.tcx.def_span(closure_def_id);
 
         let mut err = ClosureKindMismatch {
@@ -3422,7 +3422,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         found_trait_ref: ty::TraitRef<'tcx>,
         expected_trait_ref: ty::TraitRef<'tcx>,
         terr: TypeError<'tcx>,
-    ) -> Diag<'tcx> {
+    ) -> Diag<'a> {
         let self_ty = found_trait_ref.self_ty();
         let (cause, terr) = if let ty::Closure(def_id, _) = self_ty.kind() {
             (
@@ -3473,7 +3473,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         span: Span,
         found_trait_ref: ty::TraitRef<'tcx>,
         expected_trait_ref: ty::TraitRef<'tcx>,
-    ) -> Result<Diag<'tcx>, ErrorGuaranteed> {
+    ) -> Result<Diag<'a>, ErrorGuaranteed> {
         let found_trait_ref = self.resolve_vars_if_possible(found_trait_ref);
         let expected_trait_ref = self.resolve_vars_if_possible(expected_trait_ref);
 
@@ -3553,7 +3553,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
                     })
                     .unwrap_or((found_span, None, found));
 
-                self.report_arg_count_mismatch(
+                self.infcx.report_arg_count_mismatch(
                     span,
                     closure_span,
                     expected,
@@ -3569,7 +3569,7 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         &self,
         obligation: &PredicateObligation<'tcx>,
         span: Span,
-    ) -> Result<Diag<'tcx>, ErrorGuaranteed> {
+    ) -> Result<Diag<'a>, ErrorGuaranteed> {
         if !self.tcx.features().generic_const_exprs {
             let guar = self
                 .dcx()
diff --git a/tests/ui/asm/x86_64/type-check-2.rs b/tests/ui/asm/x86_64/type-check-2.rs
index c866f9fd8cc..4b5d59fdbc7 100644
--- a/tests/ui/asm/x86_64/type-check-2.rs
+++ b/tests/ui/asm/x86_64/type-check-2.rs
@@ -13,13 +13,16 @@ fn main() {
 
         let x: u64;
         asm!("{}", in(reg) x);
+        //~^ ERROR isn't initialized
         let mut y: u64;
         asm!("{}", inout(reg) y);
+        //~^ ERROR isn't initialized
         let _ = y;
 
         // Outputs require mutable places
 
         let v: Vec<u64> = vec![0, 1, 2];
+        //~^ ERROR is not declared as mutable
         asm!("{}", in(reg) v[0]);
         asm!("{}", out(reg) v[0]);
         asm!("{}", inout(reg) v[0]);
diff --git a/tests/ui/asm/x86_64/type-check-2.stderr b/tests/ui/asm/x86_64/type-check-2.stderr
index 4f3d5100af0..6ae118b16e7 100644
--- a/tests/ui/asm/x86_64/type-check-2.stderr
+++ b/tests/ui/asm/x86_64/type-check-2.stderr
@@ -1,5 +1,5 @@
 error: invalid `sym` operand
-  --> $DIR/type-check-2.rs:35:24
+  --> $DIR/type-check-2.rs:38:24
    |
 LL |         asm!("{}", sym x);
    |                        ^ is a local variable
@@ -7,7 +7,7 @@ LL |         asm!("{}", sym x);
    = help: `sym` operands must refer to either a function or a static
 
 error: invalid `sym` operand
-  --> $DIR/type-check-2.rs:86:19
+  --> $DIR/type-check-2.rs:89:19
    |
 LL | global_asm!("{}", sym C);
    |                   ^^^^^ is an `i32`
@@ -15,7 +15,7 @@ LL | global_asm!("{}", sym C);
    = help: `sym` operands must refer to either a function or a static
 
 error: invalid `sym` operand
-  --> $DIR/type-check-2.rs:33:20
+  --> $DIR/type-check-2.rs:36:20
    |
 LL |         asm!("{}", sym C);
    |                    ^^^^^ is an `i32`
@@ -23,15 +23,15 @@ LL |         asm!("{}", sym C);
    = help: `sym` operands must refer to either a function or a static
 
 error: arguments for inline assembly must be copyable
-  --> $DIR/type-check-2.rs:40:32
+  --> $DIR/type-check-2.rs:43:32
    |
 LL |         asm!("{}", in(xmm_reg) SimdNonCopy(0.0, 0.0, 0.0, 0.0));
    |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: `SimdNonCopy` does not implement the Copy trait
 
-error: cannot use value of type `{closure@$DIR/type-check-2.rs:52:28: 52:36}` for inline assembly
-  --> $DIR/type-check-2.rs:52:28
+error: cannot use value of type `{closure@$DIR/type-check-2.rs:55:28: 55:36}` for inline assembly
+  --> $DIR/type-check-2.rs:55:28
    |
 LL |         asm!("{}", in(reg) |x: i32| x);
    |                            ^^^^^^^^^^
@@ -39,7 +39,7 @@ LL |         asm!("{}", in(reg) |x: i32| x);
    = note: only integers, floats, SIMD vectors, pointers and function pointers can be used as arguments for inline assembly
 
 error: cannot use value of type `Vec<i32>` for inline assembly
-  --> $DIR/type-check-2.rs:54:28
+  --> $DIR/type-check-2.rs:57:28
    |
 LL |         asm!("{}", in(reg) vec![0]);
    |                            ^^^^^^^
@@ -48,7 +48,7 @@ LL |         asm!("{}", in(reg) vec![0]);
    = note: this error originates in the macro `vec` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: cannot use value of type `(i32, i32, i32)` for inline assembly
-  --> $DIR/type-check-2.rs:56:28
+  --> $DIR/type-check-2.rs:59:28
    |
 LL |         asm!("{}", in(reg) (1, 2, 3));
    |                            ^^^^^^^^^
@@ -56,7 +56,7 @@ LL |         asm!("{}", in(reg) (1, 2, 3));
    = note: only integers, floats, SIMD vectors, pointers and function pointers can be used as arguments for inline assembly
 
 error: cannot use value of type `[i32; 3]` for inline assembly
-  --> $DIR/type-check-2.rs:58:28
+  --> $DIR/type-check-2.rs:61:28
    |
 LL |         asm!("{}", in(reg) [1, 2, 3]);
    |                            ^^^^^^^^^
@@ -64,7 +64,7 @@ LL |         asm!("{}", in(reg) [1, 2, 3]);
    = note: only integers, floats, SIMD vectors, pointers and function pointers can be used as arguments for inline assembly
 
 error: cannot use value of type `fn() {main}` for inline assembly
-  --> $DIR/type-check-2.rs:66:31
+  --> $DIR/type-check-2.rs:69:31
    |
 LL |         asm!("{}", inout(reg) f);
    |                               ^
@@ -72,12 +72,56 @@ LL |         asm!("{}", inout(reg) f);
    = note: only integers, floats, SIMD vectors, pointers and function pointers can be used as arguments for inline assembly
 
 error: cannot use value of type `&mut i32` for inline assembly
-  --> $DIR/type-check-2.rs:69:31
+  --> $DIR/type-check-2.rs:72:31
    |
 LL |         asm!("{}", inout(reg) r);
    |                               ^
    |
    = note: only integers, floats, SIMD vectors, pointers and function pointers can be used as arguments for inline assembly
 
-error: aborting due to 10 previous errors
+error[E0381]: used binding `x` isn't initialized
+  --> $DIR/type-check-2.rs:15:28
+   |
+LL |         let x: u64;
+   |             - binding declared here but left uninitialized
+LL |         asm!("{}", in(reg) x);
+   |                            ^ `x` used here but it isn't initialized
+   |
+help: consider assigning a value
+   |
+LL |         let x: u64 = 42;
+   |                    ++++
+
+error[E0381]: used binding `y` isn't initialized
+  --> $DIR/type-check-2.rs:18:9
+   |
+LL |         let mut y: u64;
+   |             ----- binding declared here but left uninitialized
+LL |         asm!("{}", inout(reg) y);
+   |         ^^^^^^^^^^^^^^^^^^^^^^^^ `y` used here but it isn't initialized
+   |
+help: consider assigning a value
+   |
+LL |         let mut y: u64 = 42;
+   |                        ++++
+
+error[E0596]: cannot borrow `v` as mutable, as it is not declared as mutable
+  --> $DIR/type-check-2.rs:24:13
+   |
+LL |         let v: Vec<u64> = vec![0, 1, 2];
+   |             ^ not mutable
+...
+LL |         asm!("{}", out(reg) v[0]);
+   |                             - cannot borrow as mutable
+LL |         asm!("{}", inout(reg) v[0]);
+   |                               - cannot borrow as mutable
+   |
+help: consider changing this to be mutable
+   |
+LL |         let mut v: Vec<u64> = vec![0, 1, 2];
+   |             +++
+
+error: aborting due to 13 previous errors
 
+Some errors have detailed explanations: E0381, E0596.
+For more information about an error, try `rustc --explain E0381`.
diff --git a/tests/ui/associated-types/associated-types-eq-expr-path.rs b/tests/ui/associated-types/associated-types-eq-expr-path.rs
index 4561e596c66..67831f91303 100644
--- a/tests/ui/associated-types/associated-types-eq-expr-path.rs
+++ b/tests/ui/associated-types/associated-types-eq-expr-path.rs
@@ -13,4 +13,5 @@ impl Foo for isize {
 pub fn main() {
     let x: isize = Foo::<A = usize>::bar();
     //~^ ERROR associated item constraints are not allowed here
+    //~| ERROR cannot call
 }
diff --git a/tests/ui/associated-types/associated-types-eq-expr-path.stderr b/tests/ui/associated-types/associated-types-eq-expr-path.stderr
index 3d0e3e61eca..4f28b3cb2de 100644
--- a/tests/ui/associated-types/associated-types-eq-expr-path.stderr
+++ b/tests/ui/associated-types/associated-types-eq-expr-path.stderr
@@ -4,6 +4,22 @@ error[E0229]: associated item constraints are not allowed here
 LL |     let x: isize = Foo::<A = usize>::bar();
    |                          ^^^^^^^^^ associated item constraint not allowed here
 
-error: aborting due to 1 previous error
+error[E0790]: cannot call associated function on trait without specifying the corresponding `impl` type
+  --> $DIR/associated-types-eq-expr-path.rs:14:20
+   |
+LL |     fn bar() -> isize;
+   |     ------------------ `Foo::bar` defined here
+...
+LL |     let x: isize = Foo::<A = usize>::bar();
+   |                    ^^^^^^^^^^^^^^^^^^^^^^^ cannot call associated function of trait
+   |
+help: use the fully-qualified path to the only available implementation
+   |
+LL -     let x: isize = Foo::<A = usize>::bar();
+LL +     let x: isize = <isize as Foo<A = usize>>::bar();
+   |
+
+error: aborting due to 2 previous errors
 
-For more information about this error, try `rustc --explain E0229`.
+Some errors have detailed explanations: E0229, E0790.
+For more information about an error, try `rustc --explain E0229`.
diff --git a/tests/ui/const-generics/assoc_const_as_type_argument.rs b/tests/ui/const-generics/assoc_const_as_type_argument.rs
index ffc7f116a94..bec6102417c 100644
--- a/tests/ui/const-generics/assoc_const_as_type_argument.rs
+++ b/tests/ui/const-generics/assoc_const_as_type_argument.rs
@@ -8,6 +8,7 @@ fn foo<T: Trait>() {
     bar::<<T as Trait>::ASSOC>();
     //~^ ERROR: expected associated type, found associated constant `Trait::ASSOC`
     //~| ERROR: unresolved item provided when a constant was expected
+    //~| ERROR type annotations needed
 }
 
 fn main() {}
diff --git a/tests/ui/const-generics/assoc_const_as_type_argument.stderr b/tests/ui/const-generics/assoc_const_as_type_argument.stderr
index ac009546135..53edc19b28c 100644
--- a/tests/ui/const-generics/assoc_const_as_type_argument.stderr
+++ b/tests/ui/const-generics/assoc_const_as_type_argument.stderr
@@ -15,7 +15,19 @@ help: if this generic argument was intended as a const parameter, surround it wi
 LL |     bar::<{ <T as Trait>::ASSOC }>();
    |           +                     +
 
-error: aborting due to 2 previous errors
+error[E0284]: type annotations needed
+  --> $DIR/assoc_const_as_type_argument.rs:8:5
+   |
+LL |     bar::<<T as Trait>::ASSOC>();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot infer the value of the const parameter `N` declared on the function `bar`
+   |
+note: required by a const generic parameter in `bar`
+  --> $DIR/assoc_const_as_type_argument.rs:5:8
+   |
+LL | fn bar<const N: usize>() {}
+   |        ^^^^^^^^^^^^^^ required by this const generic parameter in `bar`
+
+error: aborting due to 3 previous errors
 
-Some errors have detailed explanations: E0575, E0747.
-For more information about an error, try `rustc --explain E0575`.
+Some errors have detailed explanations: E0284, E0575, E0747.
+For more information about an error, try `rustc --explain E0284`.
diff --git a/tests/ui/const-generics/const-arg-in-const-arg.min.stderr b/tests/ui/const-generics/const-arg-in-const-arg.min.stderr
index ce7fce25993..2ea9d6b35b4 100644
--- a/tests/ui/const-generics/const-arg-in-const-arg.min.stderr
+++ b/tests/ui/const-generics/const-arg-in-const-arg.min.stderr
@@ -17,7 +17,7 @@ LL |     let _: [u8; bar::<N>()];
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:18:23
+  --> $DIR/const-arg-in-const-arg.rs:19:23
    |
 LL |     let _: [u8; faz::<'a>(&())];
    |                       ^^ cannot perform const operation using `'a`
@@ -26,7 +26,7 @@ LL |     let _: [u8; faz::<'a>(&())];
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:20:23
+  --> $DIR/const-arg-in-const-arg.rs:21:23
    |
 LL |     let _: [u8; baz::<'a>(&())];
    |                       ^^ cannot perform const operation using `'a`
@@ -35,7 +35,7 @@ LL |     let _: [u8; baz::<'a>(&())];
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:21:23
+  --> $DIR/const-arg-in-const-arg.rs:22:23
    |
 LL |     let _: [u8; faz::<'b>(&())];
    |                       ^^ cannot perform const operation using `'b`
@@ -44,7 +44,7 @@ LL |     let _: [u8; faz::<'b>(&())];
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:23:23
+  --> $DIR/const-arg-in-const-arg.rs:24:23
    |
 LL |     let _: [u8; baz::<'b>(&())];
    |                       ^^ cannot perform const operation using `'b`
@@ -53,7 +53,7 @@ LL |     let _: [u8; baz::<'b>(&())];
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:26:23
+  --> $DIR/const-arg-in-const-arg.rs:27:23
    |
 LL |     let _ = [0; bar::<N>()];
    |                       ^ cannot perform const operation using `N`
@@ -62,7 +62,7 @@ LL |     let _ = [0; bar::<N>()];
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:28:23
+  --> $DIR/const-arg-in-const-arg.rs:30:23
    |
 LL |     let _ = [0; faz::<'a>(&())];
    |                       ^^ cannot perform const operation using `'a`
@@ -71,7 +71,7 @@ LL |     let _ = [0; faz::<'a>(&())];
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:30:23
+  --> $DIR/const-arg-in-const-arg.rs:32:23
    |
 LL |     let _ = [0; baz::<'a>(&())];
    |                       ^^ cannot perform const operation using `'a`
@@ -80,7 +80,7 @@ LL |     let _ = [0; baz::<'a>(&())];
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:31:23
+  --> $DIR/const-arg-in-const-arg.rs:33:23
    |
 LL |     let _ = [0; faz::<'b>(&())];
    |                       ^^ cannot perform const operation using `'b`
@@ -89,7 +89,7 @@ LL |     let _ = [0; faz::<'b>(&())];
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:33:23
+  --> $DIR/const-arg-in-const-arg.rs:35:23
    |
 LL |     let _ = [0; baz::<'b>(&())];
    |                       ^^ cannot perform const operation using `'b`
@@ -98,7 +98,7 @@ LL |     let _ = [0; baz::<'b>(&())];
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:34:24
+  --> $DIR/const-arg-in-const-arg.rs:36:24
    |
 LL |     let _: Foo<{ foo::<T>() }>;
    |                        ^ cannot perform const operation using `T`
@@ -107,7 +107,7 @@ LL |     let _: Foo<{ foo::<T>() }>;
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:35:24
+  --> $DIR/const-arg-in-const-arg.rs:37:24
    |
 LL |     let _: Foo<{ bar::<N>() }>;
    |                        ^ cannot perform const operation using `N`
@@ -116,7 +116,7 @@ LL |     let _: Foo<{ bar::<N>() }>;
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:37:24
+  --> $DIR/const-arg-in-const-arg.rs:40:24
    |
 LL |     let _: Foo<{ faz::<'a>(&()) }>;
    |                        ^^ cannot perform const operation using `'a`
@@ -125,7 +125,7 @@ LL |     let _: Foo<{ faz::<'a>(&()) }>;
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:39:24
+  --> $DIR/const-arg-in-const-arg.rs:42:24
    |
 LL |     let _: Foo<{ baz::<'a>(&()) }>;
    |                        ^^ cannot perform const operation using `'a`
@@ -134,7 +134,7 @@ LL |     let _: Foo<{ baz::<'a>(&()) }>;
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:40:24
+  --> $DIR/const-arg-in-const-arg.rs:43:24
    |
 LL |     let _: Foo<{ faz::<'b>(&()) }>;
    |                        ^^ cannot perform const operation using `'b`
@@ -143,7 +143,7 @@ LL |     let _: Foo<{ faz::<'b>(&()) }>;
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:42:24
+  --> $DIR/const-arg-in-const-arg.rs:45:24
    |
 LL |     let _: Foo<{ baz::<'b>(&()) }>;
    |                        ^^ cannot perform const operation using `'b`
@@ -152,7 +152,7 @@ LL |     let _: Foo<{ baz::<'b>(&()) }>;
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:43:27
+  --> $DIR/const-arg-in-const-arg.rs:46:27
    |
 LL |     let _ = Foo::<{ foo::<T>() }>;
    |                           ^ cannot perform const operation using `T`
@@ -161,7 +161,7 @@ LL |     let _ = Foo::<{ foo::<T>() }>;
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:44:27
+  --> $DIR/const-arg-in-const-arg.rs:47:27
    |
 LL |     let _ = Foo::<{ bar::<N>() }>;
    |                           ^ cannot perform const operation using `N`
@@ -170,7 +170,7 @@ LL |     let _ = Foo::<{ bar::<N>() }>;
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:46:27
+  --> $DIR/const-arg-in-const-arg.rs:50:27
    |
 LL |     let _ = Foo::<{ faz::<'a>(&()) }>;
    |                           ^^ cannot perform const operation using `'a`
@@ -179,7 +179,7 @@ LL |     let _ = Foo::<{ faz::<'a>(&()) }>;
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:48:27
+  --> $DIR/const-arg-in-const-arg.rs:52:27
    |
 LL |     let _ = Foo::<{ baz::<'a>(&()) }>;
    |                           ^^ cannot perform const operation using `'a`
@@ -188,7 +188,7 @@ LL |     let _ = Foo::<{ baz::<'a>(&()) }>;
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:49:27
+  --> $DIR/const-arg-in-const-arg.rs:53:27
    |
 LL |     let _ = Foo::<{ faz::<'b>(&()) }>;
    |                           ^^ cannot perform const operation using `'b`
@@ -197,7 +197,7 @@ LL |     let _ = Foo::<{ faz::<'b>(&()) }>;
    = help: add `#![feature(generic_const_exprs)]` to allow generic const expressions
 
 error: generic parameters may not be used in const operations
-  --> $DIR/const-arg-in-const-arg.rs:51:27
+  --> $DIR/const-arg-in-const-arg.rs:55:27
    |
 LL |     let _ = Foo::<{ baz::<'b>(&()) }>;
    |                           ^^ cannot perform const operation using `'b`
@@ -216,8 +216,20 @@ help: if this generic argument was intended as a const parameter, surround it wi
 LL |     let _: [u8; bar::<{ N }>()];
    |                       +   +
 
+error[E0284]: type annotations needed
+  --> $DIR/const-arg-in-const-arg.rs:16:17
+   |
+LL |     let _: [u8; bar::<N>()];
+   |                 ^^^^^^^^ cannot infer the value of the const parameter `N` declared on the function `bar`
+   |
+note: required by a const generic parameter in `bar`
+  --> $DIR/const-arg-in-const-arg.rs:9:14
+   |
+LL | const fn bar<const N: usize>() -> usize { N }
+   |              ^^^^^^^^^^^^^^ required by this const generic parameter in `bar`
+
 error[E0794]: cannot specify lifetime arguments explicitly if late bound lifetime parameters are present
-  --> $DIR/const-arg-in-const-arg.rs:18:23
+  --> $DIR/const-arg-in-const-arg.rs:19:23
    |
 LL |     let _: [u8; faz::<'a>(&())];
    |                       ^^
@@ -229,7 +241,7 @@ LL | const fn faz<'a>(_: &'a ()) -> usize { 13 }
    |              ^^
 
 error[E0794]: cannot specify lifetime arguments explicitly if late bound lifetime parameters are present
-  --> $DIR/const-arg-in-const-arg.rs:21:23
+  --> $DIR/const-arg-in-const-arg.rs:22:23
    |
 LL |     let _: [u8; faz::<'b>(&())];
    |                       ^^
@@ -241,7 +253,7 @@ LL | const fn faz<'a>(_: &'a ()) -> usize { 13 }
    |              ^^
 
 error[E0747]: unresolved item provided when a constant was expected
-  --> $DIR/const-arg-in-const-arg.rs:35:24
+  --> $DIR/const-arg-in-const-arg.rs:37:24
    |
 LL |     let _: Foo<{ bar::<N>() }>;
    |                        ^
@@ -251,8 +263,20 @@ help: if this generic argument was intended as a const parameter, surround it wi
 LL |     let _: Foo<{ bar::<{ N }>() }>;
    |                        +   +
 
+error[E0284]: type annotations needed
+  --> $DIR/const-arg-in-const-arg.rs:37:18
+   |
+LL |     let _: Foo<{ bar::<N>() }>;
+   |                  ^^^^^^^^ cannot infer the value of the const parameter `N` declared on the function `bar`
+   |
+note: required by a const generic parameter in `bar`
+  --> $DIR/const-arg-in-const-arg.rs:9:14
+   |
+LL | const fn bar<const N: usize>() -> usize { N }
+   |              ^^^^^^^^^^^^^^ required by this const generic parameter in `bar`
+
 error[E0794]: cannot specify lifetime arguments explicitly if late bound lifetime parameters are present
-  --> $DIR/const-arg-in-const-arg.rs:37:24
+  --> $DIR/const-arg-in-const-arg.rs:40:24
    |
 LL |     let _: Foo<{ faz::<'a>(&()) }>;
    |                        ^^
@@ -264,7 +288,7 @@ LL | const fn faz<'a>(_: &'a ()) -> usize { 13 }
    |              ^^
 
 error[E0794]: cannot specify lifetime arguments explicitly if late bound lifetime parameters are present
-  --> $DIR/const-arg-in-const-arg.rs:40:24
+  --> $DIR/const-arg-in-const-arg.rs:43:24
    |
 LL |     let _: Foo<{ faz::<'b>(&()) }>;
    |                        ^^
@@ -276,7 +300,7 @@ LL | const fn faz<'a>(_: &'a ()) -> usize { 13 }
    |              ^^
 
 error: constant expression depends on a generic parameter
-  --> $DIR/const-arg-in-const-arg.rs:25:17
+  --> $DIR/const-arg-in-const-arg.rs:26:17
    |
 LL |     let _ = [0; foo::<T>()];
    |                 ^^^^^^^^^^
@@ -284,7 +308,7 @@ LL |     let _ = [0; foo::<T>()];
    = note: this may fail depending on what value the parameter takes
 
 error[E0747]: unresolved item provided when a constant was expected
-  --> $DIR/const-arg-in-const-arg.rs:26:23
+  --> $DIR/const-arg-in-const-arg.rs:27:23
    |
 LL |     let _ = [0; bar::<N>()];
    |                       ^
@@ -294,8 +318,20 @@ help: if this generic argument was intended as a const parameter, surround it wi
 LL |     let _ = [0; bar::<{ N }>()];
    |                       +   +
 
+error[E0284]: type annotations needed
+  --> $DIR/const-arg-in-const-arg.rs:27:17
+   |
+LL |     let _ = [0; bar::<N>()];
+   |                 ^^^^^^^^ cannot infer the value of the const parameter `N` declared on the function `bar`
+   |
+note: required by a const generic parameter in `bar`
+  --> $DIR/const-arg-in-const-arg.rs:9:14
+   |
+LL | const fn bar<const N: usize>() -> usize { N }
+   |              ^^^^^^^^^^^^^^ required by this const generic parameter in `bar`
+
 error[E0794]: cannot specify lifetime arguments explicitly if late bound lifetime parameters are present
-  --> $DIR/const-arg-in-const-arg.rs:28:23
+  --> $DIR/const-arg-in-const-arg.rs:30:23
    |
 LL |     let _ = [0; faz::<'a>(&())];
    |                       ^^
@@ -307,7 +343,7 @@ LL | const fn faz<'a>(_: &'a ()) -> usize { 13 }
    |              ^^
 
 error[E0794]: cannot specify lifetime arguments explicitly if late bound lifetime parameters are present
-  --> $DIR/const-arg-in-const-arg.rs:31:23
+  --> $DIR/const-arg-in-const-arg.rs:33:23
    |
 LL |     let _ = [0; faz::<'b>(&())];
    |                       ^^
@@ -319,7 +355,7 @@ LL | const fn faz<'a>(_: &'a ()) -> usize { 13 }
    |              ^^
 
 error[E0747]: unresolved item provided when a constant was expected
-  --> $DIR/const-arg-in-const-arg.rs:44:27
+  --> $DIR/const-arg-in-const-arg.rs:47:27
    |
 LL |     let _ = Foo::<{ bar::<N>() }>;
    |                           ^
@@ -329,8 +365,20 @@ help: if this generic argument was intended as a const parameter, surround it wi
 LL |     let _ = Foo::<{ bar::<{ N }>() }>;
    |                           +   +
 
+error[E0284]: type annotations needed
+  --> $DIR/const-arg-in-const-arg.rs:47:21
+   |
+LL |     let _ = Foo::<{ bar::<N>() }>;
+   |                     ^^^^^^^^ cannot infer the value of the const parameter `N` declared on the function `bar`
+   |
+note: required by a const generic parameter in `bar`
+  --> $DIR/const-arg-in-const-arg.rs:9:14
+   |
+LL | const fn bar<const N: usize>() -> usize { N }
+   |              ^^^^^^^^^^^^^^ required by this const generic parameter in `bar`
+
 error[E0794]: cannot specify lifetime arguments explicitly if late bound lifetime parameters are present
-  --> $DIR/const-arg-in-const-arg.rs:46:27
+  --> $DIR/const-arg-in-const-arg.rs:50:27
    |
 LL |     let _ = Foo::<{ faz::<'a>(&()) }>;
    |                           ^^
@@ -342,7 +390,7 @@ LL | const fn faz<'a>(_: &'a ()) -> usize { 13 }
    |              ^^
 
 error[E0794]: cannot specify lifetime arguments explicitly if late bound lifetime parameters are present
-  --> $DIR/const-arg-in-const-arg.rs:49:27
+  --> $DIR/const-arg-in-const-arg.rs:53:27
    |
 LL |     let _ = Foo::<{ faz::<'b>(&()) }>;
    |                           ^^
@@ -353,7 +401,7 @@ note: the late bound lifetime parameter is introduced here
 LL | const fn faz<'a>(_: &'a ()) -> usize { 13 }
    |              ^^
 
-error: aborting due to 36 previous errors
+error: aborting due to 40 previous errors
 
-Some errors have detailed explanations: E0747, E0794.
-For more information about an error, try `rustc --explain E0747`.
+Some errors have detailed explanations: E0284, E0747, E0794.
+For more information about an error, try `rustc --explain E0284`.
diff --git a/tests/ui/const-generics/const-arg-in-const-arg.rs b/tests/ui/const-generics/const-arg-in-const-arg.rs
index 27b74489fe8..b95c63309f7 100644
--- a/tests/ui/const-generics/const-arg-in-const-arg.rs
+++ b/tests/ui/const-generics/const-arg-in-const-arg.rs
@@ -15,6 +15,7 @@ fn test<'a, 'b, T, const N: usize>() where &'b (): Sized {
     let _: [u8; foo::<T>()]; //[min]~ ERROR generic parameters may not
     let _: [u8; bar::<N>()]; //[min]~ ERROR generic parameters may not
                              //[min]~^ ERROR unresolved item provided when a constant was expected
+                             //[min]~| ERROR type annotations needed
     let _: [u8; faz::<'a>(&())]; //[min]~ ERROR generic parameters may not
                                  //[min]~^ ERROR cannot specify lifetime arguments
     let _: [u8; baz::<'a>(&())]; //[min]~ ERROR generic parameters may not
@@ -25,6 +26,7 @@ fn test<'a, 'b, T, const N: usize>() where &'b (): Sized {
     let _ = [0; foo::<T>()]; //[min]~ ERROR constant expression depends on a generic parameter
     let _ = [0; bar::<N>()]; //[min]~ ERROR generic parameters may not
                              //[min]~^ ERROR unresolved item provided when a constant was expected
+                             //[min]~| ERROR type annotations needed
     let _ = [0; faz::<'a>(&())]; //[min]~ ERROR generic parameters may not
                                  //[min]~^ ERROR cannot specify lifetime arguments
     let _ = [0; baz::<'a>(&())]; //[min]~ ERROR generic parameters may not
@@ -34,6 +36,7 @@ fn test<'a, 'b, T, const N: usize>() where &'b (): Sized {
     let _: Foo<{ foo::<T>() }>; //[min]~ ERROR generic parameters may not
     let _: Foo<{ bar::<N>() }>; //[min]~ ERROR generic parameters may not
                                 //[min]~^ ERROR unresolved item provided when a constant was expected
+                                //[min]~| ERROR type annotations needed
     let _: Foo<{ faz::<'a>(&()) }>; //[min]~ ERROR generic parameters may not
                                     //[min]~^ ERROR cannot specify lifetime arguments
     let _: Foo<{ baz::<'a>(&()) }>; //[min]~ ERROR generic parameters may not
@@ -43,6 +46,7 @@ fn test<'a, 'b, T, const N: usize>() where &'b (): Sized {
     let _ = Foo::<{ foo::<T>() }>; //[min]~ ERROR generic parameters may not
     let _ = Foo::<{ bar::<N>() }>; //[min]~ ERROR generic parameters may not
                                    //[min]~^ ERROR unresolved item provided when a constant was expected
+                                   //[min]~| ERROR type annotations needed
     let _ = Foo::<{ faz::<'a>(&()) }>; //[min]~ ERROR generic parameters may not
                                        //[min]~^ ERROR cannot specify lifetime arguments
     let _ = Foo::<{ baz::<'a>(&()) }>; //[min]~ ERROR generic parameters may not
diff --git a/tests/ui/const-generics/generic_const_exprs/opaque_type.rs b/tests/ui/const-generics/generic_const_exprs/opaque_type.rs
index 56b8acbf88c..7209290a36e 100644
--- a/tests/ui/const-generics/generic_const_exprs/opaque_type.rs
+++ b/tests/ui/const-generics/generic_const_exprs/opaque_type.rs
@@ -2,6 +2,7 @@
 #![allow(incomplete_features)]
 
 type Foo = impl Sized;
+//~^ ERROR: unconstrained opaque type
 
 fn with_bound<const N: usize>() -> Foo
 where
diff --git a/tests/ui/const-generics/generic_const_exprs/opaque_type.stderr b/tests/ui/const-generics/generic_const_exprs/opaque_type.stderr
index e9fb8c0f403..c7a266205b4 100644
--- a/tests/ui/const-generics/generic_const_exprs/opaque_type.stderr
+++ b/tests/ui/const-generics/generic_const_exprs/opaque_type.stderr
@@ -1,5 +1,5 @@
 error[E0308]: mismatched types
-  --> $DIR/opaque_type.rs:10:17
+  --> $DIR/opaque_type.rs:11:17
    |
 LL | type Foo = impl Sized;
    |            ---------- the found opaque type
@@ -11,12 +11,20 @@ LL |     let _: [u8; (N / 2) as Foo] = [0; (N / 2) as usize];
            found opaque type `Foo`
 
 error[E0605]: non-primitive cast: `usize` as `Foo`
-  --> $DIR/opaque_type.rs:10:17
+  --> $DIR/opaque_type.rs:11:17
    |
 LL |     let _: [u8; (N / 2) as Foo] = [0; (N / 2) as usize];
    |                 ^^^^^^^^^^^^^^ an `as` expression can only be used to convert between primitive types or to coerce to a specific trait object
 
-error: aborting due to 2 previous errors
+error: unconstrained opaque type
+  --> $DIR/opaque_type.rs:4:12
+   |
+LL | type Foo = impl Sized;
+   |            ^^^^^^^^^^
+   |
+   = note: `Foo` must be used in combination with a concrete type within the same module
+
+error: aborting due to 3 previous errors
 
 Some errors have detailed explanations: E0308, E0605.
 For more information about an error, try `rustc --explain E0308`.
diff --git a/tests/ui/const-generics/issues/issue-62878.min.stderr b/tests/ui/const-generics/issues/issue-62878.min.stderr
index 5205726d738..3fd50bbe298 100644
--- a/tests/ui/const-generics/issues/issue-62878.min.stderr
+++ b/tests/ui/const-generics/issues/issue-62878.min.stderr
@@ -30,7 +30,31 @@ help: add `#![feature(generic_arg_infer)]` to the crate attributes to enable
 LL + #![feature(generic_arg_infer)]
    |
 
-error: aborting due to 3 previous errors
+error[E0284]: type annotations needed
+  --> $DIR/issue-62878.rs:10:5
+   |
+LL |     foo::<_, { [1] }>();
+   |     ^^^^^^^^^^^^^^^^^ cannot infer the value of the const parameter `N` declared on the function `foo`
+   |
+note: required by a const generic parameter in `foo`
+  --> $DIR/issue-62878.rs:5:8
+   |
+LL | fn foo<const N: usize, const A: [u8; N]>() {}
+   |        ^^^^^^^^^^^^^^ required by this const generic parameter in `foo`
+
+error[E0284]: type annotations needed
+  --> $DIR/issue-62878.rs:10:5
+   |
+LL |     foo::<_, { [1] }>();
+   |     ^^^^^^^^^^^^^^^^^ cannot infer the value of the const parameter `A` declared on the function `foo`
+   |
+note: required by a const generic parameter in `foo`
+  --> $DIR/issue-62878.rs:5:24
+   |
+LL | fn foo<const N: usize, const A: [u8; N]>() {}
+   |                        ^^^^^^^^^^^^^^^^ required by this const generic parameter in `foo`
+
+error: aborting due to 5 previous errors
 
-Some errors have detailed explanations: E0747, E0770.
-For more information about an error, try `rustc --explain E0747`.
+Some errors have detailed explanations: E0284, E0747, E0770.
+For more information about an error, try `rustc --explain E0284`.
diff --git a/tests/ui/const-generics/issues/issue-62878.rs b/tests/ui/const-generics/issues/issue-62878.rs
index 0b5269df85e..c784e95edd8 100644
--- a/tests/ui/const-generics/issues/issue-62878.rs
+++ b/tests/ui/const-generics/issues/issue-62878.rs
@@ -9,4 +9,6 @@ fn foo<const N: usize, const A: [u8; N]>() {}
 fn main() {
     foo::<_, { [1] }>();
     //[min]~^ ERROR: type provided when a constant was expected
+    //[min]~| ERROR type annotations needed
+    //[min]~| ERROR type annotations needed
 }
diff --git a/tests/ui/const-generics/min_const_generics/const-expression-suggest-missing-braces.rs b/tests/ui/const-generics/min_const_generics/const-expression-suggest-missing-braces.rs
index e12e07a28e7..497c020bde4 100644
--- a/tests/ui/const-generics/min_const_generics/const-expression-suggest-missing-braces.rs
+++ b/tests/ui/const-generics/min_const_generics/const-expression-suggest-missing-braces.rs
@@ -12,6 +12,7 @@ fn b() {
     //~^ ERROR expected trait, found constant `BAR`
     //~| ERROR expected trait, found constant `BAR`
     //~| ERROR type provided when a constant was expected
+    //~| ERROR type annotations needed
 }
 fn c() {
     foo::<3 + 3>(); //~ ERROR expressions must be enclosed in braces
diff --git a/tests/ui/const-generics/min_const_generics/const-expression-suggest-missing-braces.stderr b/tests/ui/const-generics/min_const_generics/const-expression-suggest-missing-braces.stderr
index d9bcc523b1f..c2ba517f609 100644
--- a/tests/ui/const-generics/min_const_generics/const-expression-suggest-missing-braces.stderr
+++ b/tests/ui/const-generics/min_const_generics/const-expression-suggest-missing-braces.stderr
@@ -10,7 +10,7 @@ LL |     foo::<{ BAR + 3 }>();
    |           +         +
 
 error: expressions must be enclosed in braces to be used as const generic arguments
-  --> $DIR/const-expression-suggest-missing-braces.rs:17:11
+  --> $DIR/const-expression-suggest-missing-braces.rs:18:11
    |
 LL |     foo::<3 + 3>();
    |           ^^^^^
@@ -21,7 +21,7 @@ LL |     foo::<{ 3 + 3 }>();
    |           +       +
 
 error: expected one of `,` or `>`, found `-`
-  --> $DIR/const-expression-suggest-missing-braces.rs:20:15
+  --> $DIR/const-expression-suggest-missing-braces.rs:21:15
    |
 LL |     foo::<BAR - 3>();
    |               ^ expected one of `,` or `>`
@@ -32,7 +32,7 @@ LL |     foo::<{ BAR - 3 }>();
    |           +         +
 
 error: expected one of `,` or `>`, found `-`
-  --> $DIR/const-expression-suggest-missing-braces.rs:23:15
+  --> $DIR/const-expression-suggest-missing-braces.rs:24:15
    |
 LL |     foo::<BAR - BAR>();
    |               ^ expected one of `,` or `>`
@@ -43,7 +43,7 @@ LL |     foo::<{ BAR - BAR }>();
    |           +           +
 
 error: expressions must be enclosed in braces to be used as const generic arguments
-  --> $DIR/const-expression-suggest-missing-braces.rs:26:11
+  --> $DIR/const-expression-suggest-missing-braces.rs:27:11
    |
 LL |     foo::<100 - BAR>();
    |           ^^^^^^^^^
@@ -54,7 +54,7 @@ LL |     foo::<{ 100 - BAR }>();
    |           +           +
 
 error: expected one of `,` or `>`, found `(`
-  --> $DIR/const-expression-suggest-missing-braces.rs:29:19
+  --> $DIR/const-expression-suggest-missing-braces.rs:30:19
    |
 LL |     foo::<bar<i32>()>();
    |                   ^ expected one of `,` or `>`
@@ -65,7 +65,7 @@ LL |     foo::<{ bar<i32>() }>();
    |           +            +
 
 error: expected one of `,` or `>`, found `(`
-  --> $DIR/const-expression-suggest-missing-braces.rs:32:21
+  --> $DIR/const-expression-suggest-missing-braces.rs:33:21
    |
 LL |     foo::<bar::<i32>()>();
    |                     ^ expected one of `,` or `>`
@@ -76,7 +76,7 @@ LL |     foo::<{ bar::<i32>() }>();
    |           +              +
 
 error: expected one of `,` or `>`, found `(`
-  --> $DIR/const-expression-suggest-missing-braces.rs:35:21
+  --> $DIR/const-expression-suggest-missing-braces.rs:36:21
    |
 LL |     foo::<bar::<i32>() + BAR>();
    |                     ^ expected one of `,` or `>`
@@ -87,7 +87,7 @@ LL |     foo::<{ bar::<i32>() + BAR }>();
    |           +                    +
 
 error: expected one of `,` or `>`, found `(`
-  --> $DIR/const-expression-suggest-missing-braces.rs:38:21
+  --> $DIR/const-expression-suggest-missing-braces.rs:39:21
    |
 LL |     foo::<bar::<i32>() - BAR>();
    |                     ^ expected one of `,` or `>`
@@ -98,7 +98,7 @@ LL |     foo::<{ bar::<i32>() - BAR }>();
    |           +                    +
 
 error: expected one of `,` or `>`, found `-`
-  --> $DIR/const-expression-suggest-missing-braces.rs:41:15
+  --> $DIR/const-expression-suggest-missing-braces.rs:42:15
    |
 LL |     foo::<BAR - bar::<i32>()>();
    |               ^ expected one of `,` or `>`
@@ -109,7 +109,7 @@ LL |     foo::<{ BAR - bar::<i32>() }>();
    |           +                    +
 
 error: expected one of `,` or `>`, found `-`
-  --> $DIR/const-expression-suggest-missing-braces.rs:44:15
+  --> $DIR/const-expression-suggest-missing-braces.rs:45:15
    |
 LL |     foo::<BAR - bar::<i32>()>();
    |               ^ expected one of `,` or `>`
@@ -137,7 +137,19 @@ error[E0747]: type provided when a constant was expected
 LL |     foo::<BAR + BAR>();
    |           ^^^^^^^^^
 
-error: aborting due to 14 previous errors
+error[E0284]: type annotations needed
+  --> $DIR/const-expression-suggest-missing-braces.rs:11:5
+   |
+LL |     foo::<BAR + BAR>();
+   |     ^^^^^^^^^^^^^^^^ cannot infer the value of the const parameter `C` declared on the function `foo`
+   |
+note: required by a const generic parameter in `foo`
+  --> $DIR/const-expression-suggest-missing-braces.rs:1:8
+   |
+LL | fn foo<const C: usize>() {}
+   |        ^^^^^^^^^^^^^^ required by this const generic parameter in `foo`
+
+error: aborting due to 15 previous errors
 
-Some errors have detailed explanations: E0404, E0747.
-For more information about an error, try `rustc --explain E0404`.
+Some errors have detailed explanations: E0284, E0404, E0747.
+For more information about an error, try `rustc --explain E0284`.
diff --git a/tests/ui/const-generics/min_const_generics/macro-fail.rs b/tests/ui/const-generics/min_const_generics/macro-fail.rs
index 2f101ecfb1f..25726490c2c 100644
--- a/tests/ui/const-generics/min_const_generics/macro-fail.rs
+++ b/tests/ui/const-generics/min_const_generics/macro-fail.rs
@@ -16,6 +16,7 @@ fn make_marker() -> impl Marker<gimme_a_const!(marker)> {
   //~| ERROR: type provided when a constant was expected
   Example::<gimme_a_const!(marker)>
   //~^ ERROR: type provided when a constant was expected
+  //~| ERROR type annotations needed
 }
 
 fn from_marker(_: impl Marker<{
@@ -35,9 +36,11 @@ fn main() {
   }>;
 
   let _fail = Example::<external_macro!()>;
-  //~^ ERROR: type provided when a constant was expected
+  //~^ ERROR: type provided when a constant
+  //~| ERROR type annotations needed
 
   let _fail = Example::<gimme_a_const!()>;
   //~^ ERROR unexpected end of macro invocation
   //~| ERROR: type provided when a constant was expected
+  //~| ERROR type annotations needed
 }
diff --git a/tests/ui/const-generics/min_const_generics/macro-fail.stderr b/tests/ui/const-generics/min_const_generics/macro-fail.stderr
index 34764982bb0..4e183fe5b1c 100644
--- a/tests/ui/const-generics/min_const_generics/macro-fail.stderr
+++ b/tests/ui/const-generics/min_const_generics/macro-fail.stderr
@@ -1,5 +1,5 @@
 error: expected type, found `{`
-  --> $DIR/macro-fail.rs:30:27
+  --> $DIR/macro-fail.rs:31:27
    |
 LL | fn make_marker() -> impl Marker<gimme_a_const!(marker)> {
    |                                 ----------------------
@@ -13,7 +13,7 @@ LL |       ($rusty: ident) => {{ let $rusty = 3; *&$rusty }}
    = note: this error originates in the macro `gimme_a_const` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: expected type, found `{`
-  --> $DIR/macro-fail.rs:30:27
+  --> $DIR/macro-fail.rs:31:27
    |
 LL |   Example::<gimme_a_const!(marker)>
    |             ----------------------
@@ -41,7 +41,7 @@ LL |   let _fail = Example::<external_macro!()>;
    = note: this error originates in the macro `external_macro` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: unexpected end of macro invocation
-  --> $DIR/macro-fail.rs:40:25
+  --> $DIR/macro-fail.rs:42:25
    |
 LL |     macro_rules! gimme_a_const {
    |     -------------------------- when calling this macro
@@ -50,7 +50,7 @@ LL |   let _fail = Example::<gimme_a_const!()>;
    |                         ^^^^^^^^^^^^^^^^ missing tokens in macro arguments
    |
 note: while trying to match meta-variable `$rusty:ident`
-  --> $DIR/macro-fail.rs:30:8
+  --> $DIR/macro-fail.rs:31:8
    |
 LL |       ($rusty: ident) => {{ let $rusty = 3; *&$rusty }}
    |        ^^^^^^^^^^^^^
@@ -75,18 +75,63 @@ error[E0747]: type provided when a constant was expected
 LL |   Example::<gimme_a_const!(marker)>
    |             ^^^^^^^^^^^^^^^^^^^^^^
 
+error[E0284]: type annotations needed
+  --> $DIR/macro-fail.rs:17:3
+   |
+LL |   Example::<gimme_a_const!(marker)>
+   |   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ cannot infer the value of the const parameter `N` declared on the struct `Example`
+   |
+note: required by a const generic parameter in `Example`
+  --> $DIR/macro-fail.rs:1:16
+   |
+LL | struct Example<const N: usize>;
+   |                ^^^^^^^^^^^^^^ required by this const generic parameter in `Example`
+
 error[E0747]: type provided when a constant was expected
-  --> $DIR/macro-fail.rs:37:25
+  --> $DIR/macro-fail.rs:38:25
    |
 LL |   let _fail = Example::<external_macro!()>;
    |                         ^^^^^^^^^^^^^^^^^
 
 error[E0747]: type provided when a constant was expected
-  --> $DIR/macro-fail.rs:40:25
+  --> $DIR/macro-fail.rs:42:25
    |
 LL |   let _fail = Example::<gimme_a_const!()>;
    |                         ^^^^^^^^^^^^^^^^
 
-error: aborting due to 9 previous errors
+error[E0284]: type annotations needed for `Example<_>`
+  --> $DIR/macro-fail.rs:38:7
+   |
+LL |   let _fail = Example::<external_macro!()>;
+   |       ^^^^^   ---------------------------- type must be known at this point
+   |
+note: required by a const generic parameter in `Example`
+  --> $DIR/macro-fail.rs:1:16
+   |
+LL | struct Example<const N: usize>;
+   |                ^^^^^^^^^^^^^^ required by this const generic parameter in `Example`
+help: consider giving `_fail` an explicit type, where the value of const parameter `N` is specified
+   |
+LL |   let _fail: Example<N> = Example::<external_macro!()>;
+   |            ++++++++++++
+
+error[E0284]: type annotations needed for `Example<_>`
+  --> $DIR/macro-fail.rs:42:7
+   |
+LL |   let _fail = Example::<gimme_a_const!()>;
+   |       ^^^^^   --------------------------- type must be known at this point
+   |
+note: required by a const generic parameter in `Example`
+  --> $DIR/macro-fail.rs:1:16
+   |
+LL | struct Example<const N: usize>;
+   |                ^^^^^^^^^^^^^^ required by this const generic parameter in `Example`
+help: consider giving `_fail` an explicit type, where the value of const parameter `N` is specified
+   |
+LL |   let _fail: Example<N> = Example::<gimme_a_const!()>;
+   |            ++++++++++++
+
+error: aborting due to 12 previous errors
 
-For more information about this error, try `rustc --explain E0747`.
+Some errors have detailed explanations: E0284, E0747.
+For more information about an error, try `rustc --explain E0284`.
diff --git a/tests/ui/const-generics/suggest_const_for_array.rs b/tests/ui/const-generics/suggest_const_for_array.rs
index f3e5a3186cd..4d29d069375 100644
--- a/tests/ui/const-generics/suggest_const_for_array.rs
+++ b/tests/ui/const-generics/suggest_const_for_array.rs
@@ -3,8 +3,10 @@
 fn example<const N: usize>() {}
 
 fn other() {
-  example::<[usize; 3]>();
-  //~^ ERROR type provided when a const
-  example::<[usize; 4+5]>();
-  //~^ ERROR type provided when a const
+    example::<[usize; 3]>();
+    //~^ ERROR type provided when a const
+    //~| ERROR type annotations needed
+    example::<[usize; 4 + 5]>();
+    //~^ ERROR type provided when a const
+    //~| ERROR type annotations needed
 }
diff --git a/tests/ui/const-generics/suggest_const_for_array.stderr b/tests/ui/const-generics/suggest_const_for_array.stderr
index a617bf2bb0d..c867914070b 100644
--- a/tests/ui/const-generics/suggest_const_for_array.stderr
+++ b/tests/ui/const-generics/suggest_const_for_array.stderr
@@ -1,15 +1,40 @@
 error[E0747]: type provided when a constant was expected
-  --> $DIR/suggest_const_for_array.rs:6:13
+  --> $DIR/suggest_const_for_array.rs:6:15
    |
-LL |   example::<[usize; 3]>();
-   |             ^^^^^^^^^^ help: array type provided where a `usize` was expected, try: `{ 3 }`
+LL |     example::<[usize; 3]>();
+   |               ^^^^^^^^^^ help: array type provided where a `usize` was expected, try: `{ 3 }`
 
 error[E0747]: type provided when a constant was expected
-  --> $DIR/suggest_const_for_array.rs:8:13
+  --> $DIR/suggest_const_for_array.rs:9:15
    |
-LL |   example::<[usize; 4+5]>();
-   |             ^^^^^^^^^^^^ help: array type provided where a `usize` was expected, try: `{ 4+5 }`
+LL |     example::<[usize; 4 + 5]>();
+   |               ^^^^^^^^^^^^^^ help: array type provided where a `usize` was expected, try: `{ 4 + 5 }`
 
-error: aborting due to 2 previous errors
+error[E0284]: type annotations needed
+  --> $DIR/suggest_const_for_array.rs:6:5
+   |
+LL |     example::<[usize; 3]>();
+   |     ^^^^^^^^^^^^^^^^^^^^^ cannot infer the value of the const parameter `N` declared on the function `example`
+   |
+note: required by a const generic parameter in `example`
+  --> $DIR/suggest_const_for_array.rs:3:12
+   |
+LL | fn example<const N: usize>() {}
+   |            ^^^^^^^^^^^^^^ required by this const generic parameter in `example`
+
+error[E0284]: type annotations needed
+  --> $DIR/suggest_const_for_array.rs:9:5
+   |
+LL |     example::<[usize; 4 + 5]>();
+   |     ^^^^^^^^^^^^^^^^^^^^^^^^^ cannot infer the value of the const parameter `N` declared on the function `example`
+   |
+note: required by a const generic parameter in `example`
+  --> $DIR/suggest_const_for_array.rs:3:12
+   |
+LL | fn example<const N: usize>() {}
+   |            ^^^^^^^^^^^^^^ required by this const generic parameter in `example`
+
+error: aborting due to 4 previous errors
 
-For more information about this error, try `rustc --explain E0747`.
+Some errors have detailed explanations: E0284, E0747.
+For more information about an error, try `rustc --explain E0284`.
diff --git a/tests/ui/generics/generic-function-item-where-type.rs b/tests/ui/generics/generic-function-item-where-type.rs
index e1b0578cadb..0e36018389e 100644
--- a/tests/ui/generics/generic-function-item-where-type.rs
+++ b/tests/ui/generics/generic-function-item-where-type.rs
@@ -3,4 +3,5 @@ fn foo<U>() {}
 fn main() {
     foo::<main>()
     //~^ ERROR constant provided when a type was expected
+    //~| ERROR type annotations needed
 }
diff --git a/tests/ui/generics/generic-function-item-where-type.stderr b/tests/ui/generics/generic-function-item-where-type.stderr
index 00e62843cb4..5b0c9a8ee6d 100644
--- a/tests/ui/generics/generic-function-item-where-type.stderr
+++ b/tests/ui/generics/generic-function-item-where-type.stderr
@@ -7,6 +7,13 @@ LL |     foo::<main>()
    = help: `main` is a function item, not a type
    = help: function item types cannot be named directly
 
-error: aborting due to 1 previous error
+error[E0282]: type annotations needed
+  --> $DIR/generic-function-item-where-type.rs:4:5
+   |
+LL |     foo::<main>()
+   |     ^^^^^^^^^^^ cannot infer type of the type parameter `U` declared on the function `foo`
+
+error: aborting due to 2 previous errors
 
-For more information about this error, try `rustc --explain E0747`.
+Some errors have detailed explanations: E0282, E0747.
+For more information about an error, try `rustc --explain E0282`.
diff --git a/tests/ui/impl-trait/impl-fn-predefined-lifetimes.rs b/tests/ui/impl-trait/impl-fn-predefined-lifetimes.rs
index 199cbbf4fcc..8aba3de530b 100644
--- a/tests/ui/impl-trait/impl-fn-predefined-lifetimes.rs
+++ b/tests/ui/impl-trait/impl-fn-predefined-lifetimes.rs
@@ -2,6 +2,7 @@
 use std::fmt::Debug;
 
 fn a<'a>() -> impl Fn(&'a u8) -> (impl Debug + '_) {
+    //~^ ERROR cannot resolve opaque type
     |x| x
     //~^ ERROR expected generic lifetime parameter, found `'_`
 }
diff --git a/tests/ui/impl-trait/impl-fn-predefined-lifetimes.stderr b/tests/ui/impl-trait/impl-fn-predefined-lifetimes.stderr
index 6064b09ef09..c2386e8c88b 100644
--- a/tests/ui/impl-trait/impl-fn-predefined-lifetimes.stderr
+++ b/tests/ui/impl-trait/impl-fn-predefined-lifetimes.stderr
@@ -1,11 +1,19 @@
 error[E0792]: expected generic lifetime parameter, found `'_`
-  --> $DIR/impl-fn-predefined-lifetimes.rs:5:9
+  --> $DIR/impl-fn-predefined-lifetimes.rs:6:9
    |
 LL | fn a<'a>() -> impl Fn(&'a u8) -> (impl Debug + '_) {
    |                                                -- this generic parameter must be used with a generic lifetime parameter
+LL |
 LL |     |x| x
    |         ^
 
-error: aborting due to 1 previous error
+error[E0720]: cannot resolve opaque type
+  --> $DIR/impl-fn-predefined-lifetimes.rs:4:35
+   |
+LL | fn a<'a>() -> impl Fn(&'a u8) -> (impl Debug + '_) {
+   |                                   ^^^^^^^^^^^^^^^ cannot resolve opaque type
+
+error: aborting due to 2 previous errors
 
-For more information about this error, try `rustc --explain E0792`.
+Some errors have detailed explanations: E0720, E0792.
+For more information about an error, try `rustc --explain E0720`.
diff --git a/tests/ui/impl-trait/transmute/in-defining-scope.rs b/tests/ui/impl-trait/transmute/in-defining-scope.rs
index b0b77d60b24..b9a9dbc10a5 100644
--- a/tests/ui/impl-trait/transmute/in-defining-scope.rs
+++ b/tests/ui/impl-trait/transmute/in-defining-scope.rs
@@ -5,6 +5,7 @@
 use std::mem::transmute;
 fn foo() -> impl Sized {
     //~^ ERROR cycle detected when computing type of
+    //~| WARN function cannot return without recursing
     unsafe {
         transmute::<_, u8>(foo());
     }
diff --git a/tests/ui/impl-trait/transmute/in-defining-scope.stderr b/tests/ui/impl-trait/transmute/in-defining-scope.stderr
index 69812f43072..7172bfdf0d7 100644
--- a/tests/ui/impl-trait/transmute/in-defining-scope.stderr
+++ b/tests/ui/impl-trait/transmute/in-defining-scope.stderr
@@ -24,6 +24,18 @@ LL | fn foo() -> impl Sized {
    |             ^^^^^^^^^^
    = note: see https://rustc-dev-guide.rust-lang.org/overview.html#queries and https://rustc-dev-guide.rust-lang.org/query.html for more information
 
-error: aborting due to 1 previous error
+warning: function cannot return without recursing
+  --> $DIR/in-defining-scope.rs:6:1
+   |
+LL | fn foo() -> impl Sized {
+   | ^^^^^^^^^^^^^^^^^^^^^^ cannot return without recursing
+...
+LL |         transmute::<_, u8>(foo());
+   |                            ----- recursive call site
+   |
+   = help: a `loop` may express intention better if this is on purpose
+   = note: `#[warn(unconditional_recursion)]` on by default
+
+error: aborting due to 1 previous error; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0391`.
diff --git a/tests/ui/infinite/infinite-struct.rs b/tests/ui/infinite/infinite-struct.rs
index f08e10f6bdb..62f9702b9f4 100644
--- a/tests/ui/infinite/infinite-struct.rs
+++ b/tests/ui/infinite/infinite-struct.rs
@@ -1,5 +1,6 @@
 struct Take(Take);
 //~^ ERROR has infinite size
+//~| ERROR cycle
 
 // check that we don't hang trying to find the tail of a recursive struct (#79437)
 fn foo() -> Take {
diff --git a/tests/ui/infinite/infinite-struct.stderr b/tests/ui/infinite/infinite-struct.stderr
index 82d147b63cd..5896aec399d 100644
--- a/tests/ui/infinite/infinite-struct.stderr
+++ b/tests/ui/infinite/infinite-struct.stderr
@@ -10,7 +10,7 @@ LL | struct Take(Box<Take>);
    |             ++++    +
 
 error[E0072]: recursive type `Foo` has infinite size
-  --> $DIR/infinite-struct.rs:10:1
+  --> $DIR/infinite-struct.rs:11:1
    |
 LL | struct Foo {
    | ^^^^^^^^^^
@@ -26,6 +26,17 @@ error: reached the recursion limit finding the struct tail for `Take`
    |
    = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]`
 
-error: aborting due to 3 previous errors
+error[E0391]: cycle detected when computing when `Take` needs drop
+  --> $DIR/infinite-struct.rs:1:1
+   |
+LL | struct Take(Take);
+   | ^^^^^^^^^^^
+   |
+   = note: ...which immediately requires computing when `Take` needs drop again
+   = note: cycle used when computing whether `Take` needs drop
+   = note: see https://rustc-dev-guide.rust-lang.org/overview.html#queries and https://rustc-dev-guide.rust-lang.org/query.html for more information
+
+error: aborting due to 4 previous errors
 
-For more information about this error, try `rustc --explain E0072`.
+Some errors have detailed explanations: E0072, E0391.
+For more information about an error, try `rustc --explain E0072`.
diff --git a/tests/ui/static/reference-of-mut-static-unsafe-fn.rs b/tests/ui/static/reference-of-mut-static-unsafe-fn.rs
deleted file mode 100644
index 5652703a271..00000000000
--- a/tests/ui/static/reference-of-mut-static-unsafe-fn.rs
+++ /dev/null
@@ -1,26 +0,0 @@
-//@ compile-flags: --edition 2024 -Z unstable-options
-
-fn main() {}
-
-unsafe fn _foo() {
-    static mut X: i32 = 1;
-    static mut Y: i32 = 1;
-
-    let _y = &X;
-    //~^ ERROR creating a shared reference to a mutable static [E0796]
-
-    let ref _a = X;
-    //~^ ERROR creating a shared reference to a mutable static [E0796]
-
-    let ref mut _a = X;
-    //~^ ERROR creating a mutable reference to a mutable static [E0796]
-
-    let (_b, _c) = (&X, &mut Y);
-    //~^ ERROR creating a shared reference to a mutable static [E0796]
-    //~^^ ERROR creating a mutable reference to a mutable static [E0796]
-
-    foo(&X);
-    //~^ ERROR creating a shared reference to a mutable static [E0796]
-}
-
-fn foo<'a>(_x: &'a i32) {}
diff --git a/tests/ui/static/reference-of-mut-static-unsafe-fn.stderr b/tests/ui/static/reference-of-mut-static-unsafe-fn.stderr
deleted file mode 100644
index 5675d313e07..00000000000
--- a/tests/ui/static/reference-of-mut-static-unsafe-fn.stderr
+++ /dev/null
@@ -1,75 +0,0 @@
-error[E0796]: creating a shared reference to a mutable static
-  --> $DIR/reference-of-mut-static-unsafe-fn.rs:9:14
-   |
-LL |     let _y = &X;
-   |              ^^ shared reference to mutable static
-   |
-   = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
-help: use `addr_of!` instead to create a raw pointer
-   |
-LL |     let _y = addr_of!(X);
-   |              ~~~~~~~~~~~
-
-error[E0796]: creating a shared reference to a mutable static
-  --> $DIR/reference-of-mut-static-unsafe-fn.rs:12:18
-   |
-LL |     let ref _a = X;
-   |                  ^ shared reference to mutable static
-   |
-   = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
-help: use `addr_of!` instead to create a raw pointer
-   |
-LL |     let ref _a = addr_of!(X);
-   |                  ~~~~~~~~~~~
-
-error[E0796]: creating a mutable reference to a mutable static
-  --> $DIR/reference-of-mut-static-unsafe-fn.rs:15:22
-   |
-LL |     let ref mut _a = X;
-   |                      ^ mutable reference to mutable static
-   |
-   = note: this mutable reference has lifetime `'static`, but if the static gets accessed (read or written) by any other means, or any other reference is created, then any further use of this mutable reference is Undefined Behavior
-help: use `addr_of_mut!` instead to create a raw pointer
-   |
-LL |     let ref mut _a = addr_of_mut!(X);
-   |                      ~~~~~~~~~~~~~~~
-
-error[E0796]: creating a shared reference to a mutable static
-  --> $DIR/reference-of-mut-static-unsafe-fn.rs:18:21
-   |
-LL |     let (_b, _c) = (&X, &mut Y);
-   |                     ^^ shared reference to mutable static
-   |
-   = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
-help: use `addr_of!` instead to create a raw pointer
-   |
-LL |     let (_b, _c) = (addr_of!(X), &mut Y);
-   |                     ~~~~~~~~~~~
-
-error[E0796]: creating a mutable reference to a mutable static
-  --> $DIR/reference-of-mut-static-unsafe-fn.rs:18:25
-   |
-LL |     let (_b, _c) = (&X, &mut Y);
-   |                         ^^^^^^ mutable reference to mutable static
-   |
-   = note: this mutable reference has lifetime `'static`, but if the static gets accessed (read or written) by any other means, or any other reference is created, then any further use of this mutable reference is Undefined Behavior
-help: use `addr_of_mut!` instead to create a raw pointer
-   |
-LL |     let (_b, _c) = (&X, addr_of_mut!(Y));
-   |                         ~~~~~~~~~~~~~~~
-
-error[E0796]: creating a shared reference to a mutable static
-  --> $DIR/reference-of-mut-static-unsafe-fn.rs:22:9
-   |
-LL |     foo(&X);
-   |         ^^ shared reference to mutable static
-   |
-   = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
-help: use `addr_of!` instead to create a raw pointer
-   |
-LL |     foo(addr_of!(X));
-   |         ~~~~~~~~~~~
-
-error: aborting due to 6 previous errors
-
-For more information about this error, try `rustc --explain E0796`.
diff --git a/tests/ui/static/reference-of-mut-static.e2021.stderr b/tests/ui/static/reference-of-mut-static.e2021.stderr
deleted file mode 100644
index f7ad51b6157..00000000000
--- a/tests/ui/static/reference-of-mut-static.e2021.stderr
+++ /dev/null
@@ -1,91 +0,0 @@
-error: creating a shared reference to mutable static is discouraged
-  --> $DIR/reference-of-mut-static.rs:16:18
-   |
-LL |         let _y = &X;
-   |                  ^^ shared reference to mutable static
-   |
-   = note: for more information, see issue #114447 <https://github.com/rust-lang/rust/issues/114447>
-   = note: this will be a hard error in the 2024 edition
-   = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
-note: the lint level is defined here
-  --> $DIR/reference-of-mut-static.rs:6:9
-   |
-LL | #![deny(static_mut_refs)]
-   |         ^^^^^^^^^^^^^^^
-help: use `addr_of!` instead to create a raw pointer
-   |
-LL |         let _y = addr_of!(X);
-   |                  ~~~~~~~~~~~
-
-error: creating a mutable reference to mutable static is discouraged
-  --> $DIR/reference-of-mut-static.rs:20:18
-   |
-LL |         let _y = &mut X;
-   |                  ^^^^^^ mutable reference to mutable static
-   |
-   = note: for more information, see issue #114447 <https://github.com/rust-lang/rust/issues/114447>
-   = note: this will be a hard error in the 2024 edition
-   = note: this mutable reference has lifetime `'static`, but if the static gets accessed (read or written) by any other means, or any other reference is created, then any further use of this mutable reference is Undefined Behavior
-help: use `addr_of_mut!` instead to create a raw pointer
-   |
-LL |         let _y = addr_of_mut!(X);
-   |                  ~~~~~~~~~~~~~~~
-
-error: creating a shared reference to mutable static is discouraged
-  --> $DIR/reference-of-mut-static.rs:28:22
-   |
-LL |         let ref _a = X;
-   |                      ^ shared reference to mutable static
-   |
-   = note: for more information, see issue #114447 <https://github.com/rust-lang/rust/issues/114447>
-   = note: this will be a hard error in the 2024 edition
-   = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
-help: use `addr_of!` instead to create a raw pointer
-   |
-LL |         let ref _a = addr_of!(X);
-   |                      ~~~~~~~~~~~
-
-error: creating a shared reference to mutable static is discouraged
-  --> $DIR/reference-of-mut-static.rs:32:25
-   |
-LL |         let (_b, _c) = (&X, &Y);
-   |                         ^^ shared reference to mutable static
-   |
-   = note: for more information, see issue #114447 <https://github.com/rust-lang/rust/issues/114447>
-   = note: this will be a hard error in the 2024 edition
-   = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
-help: use `addr_of!` instead to create a raw pointer
-   |
-LL |         let (_b, _c) = (addr_of!(X), &Y);
-   |                         ~~~~~~~~~~~
-
-error: creating a shared reference to mutable static is discouraged
-  --> $DIR/reference-of-mut-static.rs:32:29
-   |
-LL |         let (_b, _c) = (&X, &Y);
-   |                             ^^ shared reference to mutable static
-   |
-   = note: for more information, see issue #114447 <https://github.com/rust-lang/rust/issues/114447>
-   = note: this will be a hard error in the 2024 edition
-   = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
-help: use `addr_of!` instead to create a raw pointer
-   |
-LL |         let (_b, _c) = (&X, addr_of!(Y));
-   |                             ~~~~~~~~~~~
-
-error: creating a shared reference to mutable static is discouraged
-  --> $DIR/reference-of-mut-static.rs:38:13
-   |
-LL |         foo(&X);
-   |             ^^ shared reference to mutable static
-   |
-   = note: for more information, see issue #114447 <https://github.com/rust-lang/rust/issues/114447>
-   = note: this will be a hard error in the 2024 edition
-   = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
-help: use `addr_of!` instead to create a raw pointer
-   |
-LL |         foo(addr_of!(X));
-   |             ~~~~~~~~~~~
-
-error: aborting due to 6 previous errors
-
diff --git a/tests/ui/static/reference-of-mut-static.e2024.stderr b/tests/ui/static/reference-of-mut-static.e2024.stderr
deleted file mode 100644
index 6205c10ac41..00000000000
--- a/tests/ui/static/reference-of-mut-static.e2024.stderr
+++ /dev/null
@@ -1,75 +0,0 @@
-error[E0796]: creating a shared reference to a mutable static
-  --> $DIR/reference-of-mut-static.rs:16:18
-   |
-LL |         let _y = &X;
-   |                  ^^ shared reference to mutable static
-   |
-   = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
-help: use `addr_of!` instead to create a raw pointer
-   |
-LL |         let _y = addr_of!(X);
-   |                  ~~~~~~~~~~~
-
-error[E0796]: creating a mutable reference to a mutable static
-  --> $DIR/reference-of-mut-static.rs:20:18
-   |
-LL |         let _y = &mut X;
-   |                  ^^^^^^ mutable reference to mutable static
-   |
-   = note: this mutable reference has lifetime `'static`, but if the static gets accessed (read or written) by any other means, or any other reference is created, then any further use of this mutable reference is Undefined Behavior
-help: use `addr_of_mut!` instead to create a raw pointer
-   |
-LL |         let _y = addr_of_mut!(X);
-   |                  ~~~~~~~~~~~~~~~
-
-error[E0796]: creating a shared reference to a mutable static
-  --> $DIR/reference-of-mut-static.rs:28:22
-   |
-LL |         let ref _a = X;
-   |                      ^ shared reference to mutable static
-   |
-   = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
-help: use `addr_of!` instead to create a raw pointer
-   |
-LL |         let ref _a = addr_of!(X);
-   |                      ~~~~~~~~~~~
-
-error[E0796]: creating a shared reference to a mutable static
-  --> $DIR/reference-of-mut-static.rs:32:25
-   |
-LL |         let (_b, _c) = (&X, &Y);
-   |                         ^^ shared reference to mutable static
-   |
-   = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
-help: use `addr_of!` instead to create a raw pointer
-   |
-LL |         let (_b, _c) = (addr_of!(X), &Y);
-   |                         ~~~~~~~~~~~
-
-error[E0796]: creating a shared reference to a mutable static
-  --> $DIR/reference-of-mut-static.rs:32:29
-   |
-LL |         let (_b, _c) = (&X, &Y);
-   |                             ^^ shared reference to mutable static
-   |
-   = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
-help: use `addr_of!` instead to create a raw pointer
-   |
-LL |         let (_b, _c) = (&X, addr_of!(Y));
-   |                             ~~~~~~~~~~~
-
-error[E0796]: creating a shared reference to a mutable static
-  --> $DIR/reference-of-mut-static.rs:38:13
-   |
-LL |         foo(&X);
-   |             ^^ shared reference to mutable static
-   |
-   = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
-help: use `addr_of!` instead to create a raw pointer
-   |
-LL |         foo(addr_of!(X));
-   |             ~~~~~~~~~~~
-
-error: aborting due to 6 previous errors
-
-For more information about this error, try `rustc --explain E0796`.
diff --git a/tests/ui/static/reference-of-mut-static.rs b/tests/ui/static/reference-of-mut-static.rs
deleted file mode 100644
index af2cab7dd87..00000000000
--- a/tests/ui/static/reference-of-mut-static.rs
+++ /dev/null
@@ -1,50 +0,0 @@
-//@ revisions: e2021 e2024
-
-//@ [e2021] edition:2021
-//@ [e2024] compile-flags: --edition 2024 -Z unstable-options
-
-#![deny(static_mut_refs)]
-
-use std::ptr::{addr_of, addr_of_mut};
-
-fn main() {
-    static mut X: i32 = 1;
-
-    static mut Y: i32 = 1;
-
-    unsafe {
-        let _y = &X;
-        //[e2024]~^ ERROR creating a shared reference to a mutable static [E0796]
-        //[e2021]~^^ ERROR shared reference to mutable static is discouraged [static_mut_refs]
-
-        let _y = &mut X;
-        //[e2024]~^ ERROR creating a mutable reference to a mutable static [E0796]
-        //[e2021]~^^ ERROR mutable reference to mutable static is discouraged [static_mut_refs]
-
-        let _z = addr_of_mut!(X);
-
-        let _p = addr_of!(X);
-
-        let ref _a = X;
-        //[e2024]~^ ERROR creating a shared reference to a mutable static [E0796]
-        //[e2021]~^^ ERROR shared reference to mutable static is discouraged [static_mut_refs]
-
-        let (_b, _c) = (&X, &Y);
-        //[e2024]~^ ERROR creating a shared reference to a mutable static [E0796]
-        //[e2021]~^^ ERROR shared reference to mutable static is discouraged [static_mut_refs]
-        //[e2024]~^^^ ERROR creating a shared reference to a mutable static [E0796]
-        //[e2021]~^^^^ ERROR shared reference to mutable static is discouraged [static_mut_refs]
-
-        foo(&X);
-        //[e2024]~^ ERROR creating a shared reference to a mutable static [E0796]
-        //[e2021]~^^ ERROR shared reference to mutable static is discouraged [static_mut_refs]
-
-        static mut Z: &[i32; 3] = &[0, 1, 2];
-
-        let _ = Z.len();
-        let _ = Z[0];
-        let _ = format!("{:?}", Z);
-    }
-}
-
-fn foo<'a>(_x: &'a i32) {}
diff --git a/tests/ui/static/reference-to-mut-static-safe.e2024.stderr b/tests/ui/static/reference-to-mut-static-safe.e2024.stderr
index 607c1bba135..c57b418d7b2 100644
--- a/tests/ui/static/reference-to-mut-static-safe.e2024.stderr
+++ b/tests/ui/static/reference-to-mut-static-safe.e2024.stderr
@@ -10,6 +10,15 @@ help: use `addr_of!` instead to create a raw pointer
 LL |     let _x = addr_of!(X);
    |              ~~~~~~~~~~~
 
-error: aborting due to 1 previous error
+error[E0133]: use of mutable static is unsafe and requires unsafe block
+  --> $DIR/reference-to-mut-static-safe.rs:9:15
+   |
+LL |     let _x = &X;
+   |               ^ use of mutable static
+   |
+   = note: mutable statics can be mutated by multiple threads: aliasing violations or data races will cause undefined behavior
+
+error: aborting due to 2 previous errors
 
-For more information about this error, try `rustc --explain E0796`.
+Some errors have detailed explanations: E0133, E0796.
+For more information about an error, try `rustc --explain E0133`.
diff --git a/tests/ui/static/reference-to-mut-static-safe.rs b/tests/ui/static/reference-to-mut-static-safe.rs
index de4f4be8f76..98afdadf4d2 100644
--- a/tests/ui/static/reference-to-mut-static-safe.rs
+++ b/tests/ui/static/reference-to-mut-static-safe.rs
@@ -8,6 +8,6 @@ fn main() {
 
     let _x = &X;
     //[e2024]~^ creating a shared reference to a mutable static [E0796]
-    //[e2021]~^^ use of mutable static is unsafe and requires unsafe function or block [E0133]
+    //~^^ use of mutable static is unsafe and requires unsafe
     //[e2021]~^^^ shared reference to mutable static is discouraged [static_mut_refs]
 }
diff --git a/tests/ui/static/reference-to-mut-static-unsafe-fn.rs b/tests/ui/static/reference-to-mut-static-unsafe-fn.rs
index 5652703a271..d63fd5460d8 100644
--- a/tests/ui/static/reference-to-mut-static-unsafe-fn.rs
+++ b/tests/ui/static/reference-to-mut-static-unsafe-fn.rs
@@ -3,24 +3,26 @@
 fn main() {}
 
 unsafe fn _foo() {
-    static mut X: i32 = 1;
-    static mut Y: i32 = 1;
+    unsafe {
+        static mut X: i32 = 1;
+        static mut Y: i32 = 1;
 
-    let _y = &X;
-    //~^ ERROR creating a shared reference to a mutable static [E0796]
+        let _y = &X;
+        //~^ ERROR creating a shared reference to a mutable static [E0796]
 
-    let ref _a = X;
-    //~^ ERROR creating a shared reference to a mutable static [E0796]
+        let ref _a = X;
+        //~^ ERROR creating a shared reference to a mutable static [E0796]
 
-    let ref mut _a = X;
-    //~^ ERROR creating a mutable reference to a mutable static [E0796]
+        let ref mut _a = X;
+        //~^ ERROR creating a mutable reference to a mutable static [E0796]
 
-    let (_b, _c) = (&X, &mut Y);
-    //~^ ERROR creating a shared reference to a mutable static [E0796]
-    //~^^ ERROR creating a mutable reference to a mutable static [E0796]
+        let (_b, _c) = (&X, &mut Y);
+        //~^ ERROR creating a shared reference to a mutable static [E0796]
+        //~^^ ERROR creating a mutable reference to a mutable static [E0796]
 
-    foo(&X);
-    //~^ ERROR creating a shared reference to a mutable static [E0796]
+        foo(&X);
+        //~^ ERROR creating a shared reference to a mutable static [E0796]
+    }
 }
 
 fn foo<'a>(_x: &'a i32) {}
diff --git a/tests/ui/static/reference-to-mut-static-unsafe-fn.stderr b/tests/ui/static/reference-to-mut-static-unsafe-fn.stderr
index 77d2aa5d1ae..b24943cf593 100644
--- a/tests/ui/static/reference-to-mut-static-unsafe-fn.stderr
+++ b/tests/ui/static/reference-to-mut-static-unsafe-fn.stderr
@@ -1,74 +1,74 @@
 error[E0796]: creating a shared reference to a mutable static
-  --> $DIR/reference-to-mut-static-unsafe-fn.rs:9:14
+  --> $DIR/reference-to-mut-static-unsafe-fn.rs:10:18
    |
-LL |     let _y = &X;
-   |              ^^ shared reference to mutable static
+LL |         let _y = &X;
+   |                  ^^ shared reference to mutable static
    |
    = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
 help: use `addr_of!` instead to create a raw pointer
    |
-LL |     let _y = addr_of!(X);
-   |              ~~~~~~~~~~~
+LL |         let _y = addr_of!(X);
+   |                  ~~~~~~~~~~~
 
 error[E0796]: creating a shared reference to a mutable static
-  --> $DIR/reference-to-mut-static-unsafe-fn.rs:12:18
+  --> $DIR/reference-to-mut-static-unsafe-fn.rs:13:22
    |
-LL |     let ref _a = X;
-   |                  ^ shared reference to mutable static
+LL |         let ref _a = X;
+   |                      ^ shared reference to mutable static
    |
    = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
 help: use `addr_of!` instead to create a raw pointer
    |
-LL |     let ref _a = addr_of!(X);
-   |                  ~~~~~~~~~~~
+LL |         let ref _a = addr_of!(X);
+   |                      ~~~~~~~~~~~
 
 error[E0796]: creating a mutable reference to a mutable static
-  --> $DIR/reference-to-mut-static-unsafe-fn.rs:15:22
+  --> $DIR/reference-to-mut-static-unsafe-fn.rs:16:26
    |
-LL |     let ref mut _a = X;
-   |                      ^ mutable reference to mutable static
+LL |         let ref mut _a = X;
+   |                          ^ mutable reference to mutable static
    |
    = note: this mutable reference has lifetime `'static`, but if the static gets accessed (read or written) by any other means, or any other reference is created, then any further use of this mutable reference is Undefined Behavior
 help: use `addr_of_mut!` instead to create a raw pointer
    |
-LL |     let ref mut _a = addr_of_mut!(X);
-   |                      ~~~~~~~~~~~~~~~
+LL |         let ref mut _a = addr_of_mut!(X);
+   |                          ~~~~~~~~~~~~~~~
 
 error[E0796]: creating a shared reference to a mutable static
-  --> $DIR/reference-to-mut-static-unsafe-fn.rs:18:21
+  --> $DIR/reference-to-mut-static-unsafe-fn.rs:19:25
    |
-LL |     let (_b, _c) = (&X, &mut Y);
-   |                     ^^ shared reference to mutable static
+LL |         let (_b, _c) = (&X, &mut Y);
+   |                         ^^ shared reference to mutable static
    |
    = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
 help: use `addr_of!` instead to create a raw pointer
    |
-LL |     let (_b, _c) = (addr_of!(X), &mut Y);
-   |                     ~~~~~~~~~~~
+LL |         let (_b, _c) = (addr_of!(X), &mut Y);
+   |                         ~~~~~~~~~~~
 
 error[E0796]: creating a mutable reference to a mutable static
-  --> $DIR/reference-to-mut-static-unsafe-fn.rs:18:25
+  --> $DIR/reference-to-mut-static-unsafe-fn.rs:19:29
    |
-LL |     let (_b, _c) = (&X, &mut Y);
-   |                         ^^^^^^ mutable reference to mutable static
+LL |         let (_b, _c) = (&X, &mut Y);
+   |                             ^^^^^^ mutable reference to mutable static
    |
    = note: this mutable reference has lifetime `'static`, but if the static gets accessed (read or written) by any other means, or any other reference is created, then any further use of this mutable reference is Undefined Behavior
 help: use `addr_of_mut!` instead to create a raw pointer
    |
-LL |     let (_b, _c) = (&X, addr_of_mut!(Y));
-   |                         ~~~~~~~~~~~~~~~
+LL |         let (_b, _c) = (&X, addr_of_mut!(Y));
+   |                             ~~~~~~~~~~~~~~~
 
 error[E0796]: creating a shared reference to a mutable static
-  --> $DIR/reference-to-mut-static-unsafe-fn.rs:22:9
+  --> $DIR/reference-to-mut-static-unsafe-fn.rs:23:13
    |
-LL |     foo(&X);
-   |         ^^ shared reference to mutable static
+LL |         foo(&X);
+   |             ^^ shared reference to mutable static
    |
    = note: this shared reference has lifetime `'static`, but if the static ever gets mutated, or a mutable reference is created, then any further use of this shared reference is Undefined Behavior
 help: use `addr_of!` instead to create a raw pointer
    |
-LL |     foo(addr_of!(X));
-   |         ~~~~~~~~~~~
+LL |         foo(addr_of!(X));
+   |             ~~~~~~~~~~~
 
 error: aborting due to 6 previous errors
 
diff --git a/tests/ui/type-alias-impl-trait/hkl_forbidden4.stderr b/tests/ui/type-alias-impl-trait/hkl_forbidden4.stderr
index 7df1a08bc88..0c2772683a9 100644
--- a/tests/ui/type-alias-impl-trait/hkl_forbidden4.stderr
+++ b/tests/ui/type-alias-impl-trait/hkl_forbidden4.stderr
@@ -44,18 +44,6 @@ LL |
 LL |     call(operation).await
    |     ^^^^^^^^^^^^^^^
 
-error[E0792]: expected generic lifetime parameter, found `'any`
-  --> $DIR/hkl_forbidden4.rs:23:1
-   |
-LL |   type FutNothing<'a> = impl 'a + Future<Output = ()>;
-   |                   -- this generic parameter must be used with a generic lifetime parameter
-...
-LL | / {
-LL | |
-LL | |
-LL | | }
-   | |_^
-
 error: concrete type differs from previous defining opaque type use
   --> $DIR/hkl_forbidden4.rs:13:1
    |
@@ -68,6 +56,18 @@ note: previous use here
 LL |     call(operation).await
    |     ^^^^^^^^^^^^^^^
 
+error[E0792]: expected generic lifetime parameter, found `'any`
+  --> $DIR/hkl_forbidden4.rs:23:1
+   |
+LL |   type FutNothing<'a> = impl 'a + Future<Output = ()>;
+   |                   -- this generic parameter must be used with a generic lifetime parameter
+...
+LL | / {
+LL | |
+LL | |
+LL | | }
+   | |_^
+
 error: aborting due to 6 previous errors
 
 For more information about this error, try `rustc --explain E0792`.
diff --git a/tests/ui/type-alias-impl-trait/issue-53092-2.rs b/tests/ui/type-alias-impl-trait/issue-53092-2.rs
index 61b23a3a933..2adfad4fc5b 100644
--- a/tests/ui/type-alias-impl-trait/issue-53092-2.rs
+++ b/tests/ui/type-alias-impl-trait/issue-53092-2.rs
@@ -5,6 +5,8 @@ type Bug<T, U> = impl Fn(T) -> U + Copy; //~ ERROR cycle detected
 
 const CONST_BUG: Bug<u8, ()> = unsafe { std::mem::transmute(|_: u8| ()) };
 //~^ ERROR: non-defining opaque type use
+//~| ERROR: item does not constrain
+//~| ERROR: item does not constrain
 
 fn make_bug<T, U: From<T>>() -> Bug<T, U> {
     |x| x.into() //~ ERROR the trait bound `U: From<T>` is not satisfied
diff --git a/tests/ui/type-alias-impl-trait/issue-53092-2.stderr b/tests/ui/type-alias-impl-trait/issue-53092-2.stderr
index c2da5fc265c..121f765e667 100644
--- a/tests/ui/type-alias-impl-trait/issue-53092-2.stderr
+++ b/tests/ui/type-alias-impl-trait/issue-53092-2.stderr
@@ -36,14 +36,40 @@ LL | type Bug<T, U> = impl Fn(T) -> U + Copy;
    |                  ^^^^^^^^^^^^^^^^^^^^^^
    = note: see https://rustc-dev-guide.rust-lang.org/overview.html#queries and https://rustc-dev-guide.rust-lang.org/query.html for more information
 
+error: item does not constrain `Bug::{opaque#0}`, but has it in its signature
+  --> $DIR/issue-53092-2.rs:6:7
+   |
+LL | const CONST_BUG: Bug<u8, ()> = unsafe { std::mem::transmute(|_: u8| ()) };
+   |       ^^^^^^^^^
+   |
+   = note: consider moving the opaque type's declaration and defining uses into a separate module
+note: this opaque type is in the signature
+  --> $DIR/issue-53092-2.rs:4:18
+   |
+LL | type Bug<T, U> = impl Fn(T) -> U + Copy;
+   |                  ^^^^^^^^^^^^^^^^^^^^^^
+
+error: item does not constrain `Bug::{opaque#0}`, but has it in its signature
+  --> $DIR/issue-53092-2.rs:6:61
+   |
+LL | const CONST_BUG: Bug<u8, ()> = unsafe { std::mem::transmute(|_: u8| ()) };
+   |                                                             ^^^^^^^
+   |
+   = note: consider moving the opaque type's declaration and defining uses into a separate module
+note: this opaque type is in the signature
+  --> $DIR/issue-53092-2.rs:4:18
+   |
+LL | type Bug<T, U> = impl Fn(T) -> U + Copy;
+   |                  ^^^^^^^^^^^^^^^^^^^^^^
+
 error[E0277]: the trait bound `U: From<T>` is not satisfied
-  --> $DIR/issue-53092-2.rs:10:5
+  --> $DIR/issue-53092-2.rs:12:5
    |
 LL |     |x| x.into()
    |     ^^^^^^^^^^^^ the trait `From<T>` is not implemented for `U`
    |
 note: required by a bound in `make_bug`
-  --> $DIR/issue-53092-2.rs:9:19
+  --> $DIR/issue-53092-2.rs:11:19
    |
 LL | fn make_bug<T, U: From<T>>() -> Bug<T, U> {
    |                   ^^^^^^^ required by this bound in `make_bug`
@@ -52,7 +78,7 @@ help: consider restricting type parameter `U`
 LL | type Bug<T, U: std::convert::From<T>> = impl Fn(T) -> U + Copy;
    |              +++++++++++++++++++++++
 
-error: aborting due to 3 previous errors
+error: aborting due to 5 previous errors
 
 Some errors have detailed explanations: E0277, E0391, E0792.
 For more information about an error, try `rustc --explain E0277`.