diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
index 44e4dea3481..2676e3009db 100644
--- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
@@ -3018,7 +3018,6 @@ fn explain_deref_coercion(&mut self, loan: &BorrowData<'tcx>, err: &mut Diagnost
     /// assignment to `x.f`).
     pub(crate) fn report_illegal_reassignment(
         &mut self,
-        _location: Location,
         (place, span): (Place<'tcx>, Span),
         assigned_span: Span,
         err_place: Place<'tcx>,
diff --git a/compiler/rustc_borrowck/src/lib.rs b/compiler/rustc_borrowck/src/lib.rs
index 4dba34c11f9..e8ffab9307e 100644
--- a/compiler/rustc_borrowck/src/lib.rs
+++ b/compiler/rustc_borrowck/src/lib.rs
@@ -1036,7 +1036,6 @@ fn check_access_for_conflict(
             self,
             self.infcx.tcx,
             self.body,
-            location,
             (sd, place_span.0),
             &borrow_set,
             |borrow_index| borrows_in_scope.contains(borrow_index),
@@ -2174,7 +2173,7 @@ fn check_access_permissions(
                 // report the error as an illegal reassignment
                 let init = &self.move_data.inits[init_index];
                 let assigned_span = init.span(self.body);
-                self.report_illegal_reassignment(location, (place, span), assigned_span, place);
+                self.report_illegal_reassignment((place, span), assigned_span, place);
             } else {
                 self.report_mutability_error(place, span, the_place_err, error_access, location)
             }
diff --git a/compiler/rustc_borrowck/src/path_utils.rs b/compiler/rustc_borrowck/src/path_utils.rs
index adafad7fa2f..88b20bba9fb 100644
--- a/compiler/rustc_borrowck/src/path_utils.rs
+++ b/compiler/rustc_borrowck/src/path_utils.rs
@@ -27,7 +27,6 @@ pub(super) fn each_borrow_involving_path<'tcx, F, I, S>(
     s: &mut S,
     tcx: TyCtxt<'tcx>,
     body: &Body<'tcx>,
-    _location: Location,
     access_place: (AccessDepth, Place<'tcx>),
     borrow_set: &BorrowSet<'tcx>,
     is_candidate: I,
diff --git a/compiler/rustc_borrowck/src/polonius/loan_invalidations.rs b/compiler/rustc_borrowck/src/polonius/loan_invalidations.rs
index 93aae1a7f97..10941cadcbb 100644
--- a/compiler/rustc_borrowck/src/polonius/loan_invalidations.rs
+++ b/compiler/rustc_borrowck/src/polonius/loan_invalidations.rs
@@ -340,7 +340,6 @@ fn check_access_for_conflict(
             self,
             self.tcx,
             self.body,
-            location,
             (sd, place),
             self.borrow_set,
             |_| true,
diff --git a/compiler/rustc_borrowck/src/region_infer/mod.rs b/compiler/rustc_borrowck/src/region_infer/mod.rs
index 3153b709ffe..34d60fc8f6e 100644
--- a/compiler/rustc_borrowck/src/region_infer/mod.rs
+++ b/compiler/rustc_borrowck/src/region_infer/mod.rs
@@ -662,7 +662,7 @@ pub(super) fn solve(
         polonius_output: Option<Rc<PoloniusOutput>>,
     ) -> (Option<ClosureRegionRequirements<'tcx>>, RegionErrors<'tcx>) {
         let mir_def_id = body.source.def_id();
-        self.propagate_constraints(body);
+        self.propagate_constraints();
 
         let mut errors_buffer = RegionErrors::new(infcx.tcx);
 
@@ -716,8 +716,8 @@ pub(super) fn solve(
     /// for each region variable until all the constraints are
     /// satisfied. Note that some values may grow **too** large to be
     /// feasible, but we check this later.
-    #[instrument(skip(self, _body), level = "debug")]
-    fn propagate_constraints(&mut self, _body: &Body<'tcx>) {
+    #[instrument(skip(self), level = "debug")]
+    fn propagate_constraints(&mut self) {
         debug!("constraints={:#?}", {
             let mut constraints: Vec<_> = self.outlives_constraints().collect();
             constraints.sort_by_key(|c| (c.sup, c.sub));
diff --git a/compiler/rustc_const_eval/src/transform/check_consts/resolver.rs b/compiler/rustc_const_eval/src/transform/check_consts/resolver.rs
index a23922c778f..2c835f6750f 100644
--- a/compiler/rustc_const_eval/src/transform/check_consts/resolver.rs
+++ b/compiler/rustc_const_eval/src/transform/check_consts/resolver.rs
@@ -96,7 +96,7 @@ fn apply_call_return_effect(
         });
     }
 
-    fn address_of_allows_mutation(&self, _mt: mir::Mutability, _place: mir::Place<'tcx>) -> bool {
+    fn address_of_allows_mutation(&self) -> bool {
         // Exact set of permissions granted by AddressOf is undecided. Conservatively assume that
         // it might allow mutation until resolution of #56604.
         true
@@ -171,10 +171,8 @@ fn visit_rvalue(&mut self, rvalue: &mir::Rvalue<'tcx>, location: Location) {
         self.super_rvalue(rvalue, location);
 
         match rvalue {
-            mir::Rvalue::AddressOf(mt, borrowed_place) => {
-                if !borrowed_place.is_indirect()
-                    && self.address_of_allows_mutation(*mt, *borrowed_place)
-                {
+            mir::Rvalue::AddressOf(_mt, borrowed_place) => {
+                if !borrowed_place.is_indirect() && self.address_of_allows_mutation() {
                     let place_ty = borrowed_place.ty(self.ccx.body, self.ccx.tcx).ty;
                     if Q::in_any_value_of_ty(self.ccx, place_ty) {
                         self.state.qualif.insert(borrowed_place.local);
diff --git a/compiler/rustc_hir_analysis/src/check/region.rs b/compiler/rustc_hir_analysis/src/check/region.rs
index 1c0a1a69513..0f5fd7e99b7 100644
--- a/compiler/rustc_hir_analysis/src/check/region.rs
+++ b/compiler/rustc_hir_analysis/src/check/region.rs
@@ -16,7 +16,6 @@
 use rustc_middle::middle::region::*;
 use rustc_middle::ty::TyCtxt;
 use rustc_span::source_map;
-use rustc_span::Span;
 
 use super::errs::{maybe_expr_static_mut, maybe_stmt_static_mut};
 
@@ -72,11 +71,7 @@ struct RegionResolutionVisitor<'tcx> {
 }
 
 /// Records the lifetime of a local variable as `cx.var_parent`
-fn record_var_lifetime(
-    visitor: &mut RegionResolutionVisitor<'_>,
-    var_id: hir::ItemLocalId,
-    _sp: Span,
-) {
+fn record_var_lifetime(visitor: &mut RegionResolutionVisitor<'_>, var_id: hir::ItemLocalId) {
     match visitor.cx.var_parent {
         None => {
             // this can happen in extern fn declarations like
@@ -210,7 +205,7 @@ fn resolve_pat<'tcx>(visitor: &mut RegionResolutionVisitor<'tcx>, pat: &'tcx hir
 
     // If this is a binding then record the lifetime of that binding.
     if let PatKind::Binding(..) = pat.kind {
-        record_var_lifetime(visitor, pat.hir_id.local_id, pat.span);
+        record_var_lifetime(visitor, pat.hir_id.local_id);
     }
 
     debug!("resolve_pat - pre-increment {} pat = {:?}", visitor.expr_and_pat_count, pat);
diff --git a/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs b/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs
index 1b6a39d8162..ec8ea77b749 100644
--- a/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs
+++ b/compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs
@@ -425,9 +425,7 @@ fn check_predicates<'tcx>(
 
     let mut res = Ok(());
     for (clause, span) in impl1_predicates {
-        if !impl2_predicates
-            .iter()
-            .any(|pred2| trait_predicates_eq(tcx, clause.as_predicate(), *pred2, span))
+        if !impl2_predicates.iter().any(|pred2| trait_predicates_eq(clause.as_predicate(), *pred2))
         {
             res = res.and(check_specialization_on(tcx, clause, span))
         }
@@ -459,10 +457,8 @@ fn check_predicates<'tcx>(
 ///
 /// So we make that check in this function and try to raise a helpful error message.
 fn trait_predicates_eq<'tcx>(
-    _tcx: TyCtxt<'tcx>,
     predicate1: ty::Predicate<'tcx>,
     predicate2: ty::Predicate<'tcx>,
-    _span: Span,
 ) -> bool {
     // FIXME(effects)
     predicate1 == predicate2
diff --git a/compiler/rustc_hir_typeck/src/expr.rs b/compiler/rustc_hir_typeck/src/expr.rs
index 31c97aab7fb..124a94c498c 100644
--- a/compiler/rustc_hir_typeck/src/expr.rs
+++ b/compiler/rustc_hir_typeck/src/expr.rs
@@ -346,7 +346,7 @@ fn check_expr_kind(
             }
             ExprKind::DropTemps(e) => self.check_expr_with_expectation(e, expected),
             ExprKind::Array(args) => self.check_expr_array(args, expected, expr),
-            ExprKind::ConstBlock(ref block) => self.check_expr_const_block(block, expected, expr),
+            ExprKind::ConstBlock(ref block) => self.check_expr_const_block(block, expected),
             ExprKind::Repeat(element, ref count) => {
                 self.check_expr_repeat(element, count, expected, expr)
             }
@@ -1487,7 +1487,6 @@ fn check_expr_const_block(
         &self,
         block: &'tcx hir::ConstBlock,
         expected: Expectation<'tcx>,
-        _expr: &'tcx hir::Expr<'tcx>,
     ) -> Ty<'tcx> {
         let body = self.tcx.hir().body(block.body);
 
diff --git a/compiler/rustc_hir_typeck/src/expr_use_visitor.rs b/compiler/rustc_hir_typeck/src/expr_use_visitor.rs
index 3ecf6c5e428..04fb7bcf4f3 100644
--- a/compiler/rustc_hir_typeck/src/expr_use_visitor.rs
+++ b/compiler/rustc_hir_typeck/src/expr_use_visitor.rs
@@ -142,7 +142,7 @@ pub fn consume_body(&mut self, body: &hir::Body<'_>) {
             let param_ty = return_if_err!(self.mc.pat_ty_adjusted(param.pat));
             debug!("consume_body: param_ty = {:?}", param_ty);
 
-            let param_place = self.mc.cat_rvalue(param.hir_id, param.pat.span, param_ty);
+            let param_place = self.mc.cat_rvalue(param.hir_id, param_ty);
 
             self.walk_irrefutable_pat(&param_place, param.pat);
         }
diff --git a/compiler/rustc_hir_typeck/src/mem_categorization.rs b/compiler/rustc_hir_typeck/src/mem_categorization.rs
index f9297550c57..fefaf996725 100644
--- a/compiler/rustc_hir_typeck/src/mem_categorization.rs
+++ b/compiler/rustc_hir_typeck/src/mem_categorization.rs
@@ -273,7 +273,7 @@ fn cat_expr_adjusted_with<F>(
                         deref.region,
                         ty::TypeAndMut { ty: target, mutbl: deref.mutbl },
                     );
-                    self.cat_rvalue(expr.hir_id, expr.span, ref_ty)
+                    self.cat_rvalue(expr.hir_id, ref_ty)
                 } else {
                     previous()?
                 };
@@ -285,7 +285,7 @@ fn cat_expr_adjusted_with<F>(
             | adjustment::Adjust::Borrow(_)
             | adjustment::Adjust::DynStar => {
                 // Result is an rvalue.
-                Ok(self.cat_rvalue(expr.hir_id, expr.span, target))
+                Ok(self.cat_rvalue(expr.hir_id, target))
             }
         }
     }
@@ -374,7 +374,7 @@ pub(crate) fn cat_expr_unadjusted(
             | hir::ExprKind::Repeat(..)
             | hir::ExprKind::InlineAsm(..)
             | hir::ExprKind::OffsetOf(..)
-            | hir::ExprKind::Err(_) => Ok(self.cat_rvalue(expr.hir_id, expr.span, expr_ty)),
+            | hir::ExprKind::Err(_) => Ok(self.cat_rvalue(expr.hir_id, expr_ty)),
         }
     }
 
@@ -396,7 +396,7 @@ pub(crate) fn cat_res(
                 | DefKind::AssocFn,
                 _,
             )
-            | Res::SelfCtor(..) => Ok(self.cat_rvalue(hir_id, span, expr_ty)),
+            | Res::SelfCtor(..) => Ok(self.cat_rvalue(hir_id, expr_ty)),
 
             Res::Def(DefKind::Static(_), _) => {
                 Ok(PlaceWithHirId::new(hir_id, expr_ty, PlaceBase::StaticItem, Vec::new()))
@@ -433,13 +433,7 @@ fn cat_upvar(&self, hir_id: hir::HirId, var_id: hir::HirId) -> McResult<PlaceWit
     }
 
     #[instrument(level = "debug", skip(self), ret)]
-    pub(crate) fn cat_rvalue(
-        &self,
-        hir_id: hir::HirId,
-        // FIXME: remove
-        _span: Span,
-        expr_ty: Ty<'tcx>,
-    ) -> PlaceWithHirId<'tcx> {
+    pub(crate) fn cat_rvalue(&self, hir_id: hir::HirId, expr_ty: Ty<'tcx>) -> PlaceWithHirId<'tcx> {
         PlaceWithHirId::new(hir_id, expr_ty, PlaceBase::Rvalue, Vec::new())
     }
 
@@ -487,7 +481,7 @@ fn cat_overloaded_place(
         };
         let ref_ty = Ty::new_ref(self.tcx(), region, ty::TypeAndMut { ty: place_ty, mutbl });
 
-        let base = self.cat_rvalue(expr.hir_id, expr.span, ref_ty);
+        let base = self.cat_rvalue(expr.hir_id, ref_ty);
         self.cat_deref(expr, base)
     }
 
diff --git a/compiler/rustc_mir_transform/src/coroutine.rs b/compiler/rustc_mir_transform/src/coroutine.rs
index 297b2fa143d..a0851aa557b 100644
--- a/compiler/rustc_mir_transform/src/coroutine.rs
+++ b/compiler/rustc_mir_transform/src/coroutine.rs
@@ -726,7 +726,7 @@ fn replace_resume_ty_local<'tcx>(
 /// The async lowering step and the type / lifetime inference / checking are
 /// still using the `resume` argument for the time being. After this transform,
 /// the coroutine body doesn't have the `resume` argument.
-fn transform_gen_context<'tcx>(_tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
+fn transform_gen_context<'tcx>(body: &mut Body<'tcx>) {
     // This leaves the local representing the `resume` argument in place,
     // but turns it into a regular local variable. This is cheaper than
     // adjusting all local references in the body after removing it.
@@ -1733,7 +1733,7 @@ fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
 
         // Remove the context argument within generator bodies.
         if matches!(coroutine_kind, CoroutineKind::Desugared(CoroutineDesugaring::Gen, _)) {
-            transform_gen_context(tcx, body);
+            transform_gen_context(body);
         }
 
         // The original arguments to the function are no longer arguments, mark them as such.
diff --git a/compiler/rustc_mir_transform/src/instsimplify.rs b/compiler/rustc_mir_transform/src/instsimplify.rs
index f65eb5cbea9..06df89c1037 100644
--- a/compiler/rustc_mir_transform/src/instsimplify.rs
+++ b/compiler/rustc_mir_transform/src/instsimplify.rs
@@ -29,17 +29,14 @@ fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
                         ctx.simplify_bool_cmp(&statement.source_info, rvalue);
                         ctx.simplify_ref_deref(&statement.source_info, rvalue);
                         ctx.simplify_len(&statement.source_info, rvalue);
-                        ctx.simplify_cast(&statement.source_info, rvalue);
+                        ctx.simplify_cast(rvalue);
                     }
                     _ => {}
                 }
             }
 
             ctx.simplify_primitive_clone(block.terminator.as_mut().unwrap(), &mut block.statements);
-            ctx.simplify_intrinsic_assert(
-                block.terminator.as_mut().unwrap(),
-                &mut block.statements,
-            );
+            ctx.simplify_intrinsic_assert(block.terminator.as_mut().unwrap());
             ctx.simplify_nounwind_call(block.terminator.as_mut().unwrap());
             simplify_duplicate_switch_targets(block.terminator.as_mut().unwrap());
         }
@@ -143,7 +140,7 @@ fn simplify_len(&self, source_info: &SourceInfo, rvalue: &mut Rvalue<'tcx>) {
         }
     }
 
-    fn simplify_cast(&self, _source_info: &SourceInfo, rvalue: &mut Rvalue<'tcx>) {
+    fn simplify_cast(&self, rvalue: &mut Rvalue<'tcx>) {
         if let Rvalue::Cast(kind, operand, cast_ty) = rvalue {
             let operand_ty = operand.ty(self.local_decls, self.tcx);
             if operand_ty == *cast_ty {
@@ -277,11 +274,7 @@ fn simplify_nounwind_call(&self, terminator: &mut Terminator<'tcx>) {
         }
     }
 
-    fn simplify_intrinsic_assert(
-        &self,
-        terminator: &mut Terminator<'tcx>,
-        _statements: &mut Vec<Statement<'tcx>>,
-    ) {
+    fn simplify_intrinsic_assert(&self, terminator: &mut Terminator<'tcx>) {
         let TerminatorKind::Call { func, target, .. } = &mut terminator.kind else {
             return;
         };
diff --git a/compiler/rustc_passes/src/check_attr.rs b/compiler/rustc_passes/src/check_attr.rs
index c24827ea902..d8ae82d11bc 100644
--- a/compiler/rustc_passes/src/check_attr.rs
+++ b/compiler/rustc_passes/src/check_attr.rs
@@ -197,7 +197,7 @@ fn check_attributes(
                 | sym::unstable
                 | sym::stable
                 | sym::rustc_allowed_through_unstable_modules
-                | sym::rustc_promotable => self.check_stability_promotable(attr, span, target),
+                | sym::rustc_promotable => self.check_stability_promotable(attr, target),
                 sym::link_ordinal => self.check_link_ordinal(attr, span, target),
                 sym::rustc_confusables => self.check_confusables(attr, target),
                 sym::rustc_safe_intrinsic => {
@@ -2099,7 +2099,7 @@ fn check_rustc_std_internal_symbol(
         }
     }
 
-    fn check_stability_promotable(&self, attr: &Attribute, _span: Span, target: Target) -> bool {
+    fn check_stability_promotable(&self, attr: &Attribute, target: Target) -> bool {
         match target {
             Target::Expression => {
                 self.dcx().emit_err(errors::StabilityPromotable { attr_span: attr.span });
diff --git a/compiler/rustc_symbol_mangling/src/typeid/typeid_itanium_cxx_abi.rs b/compiler/rustc_symbol_mangling/src/typeid/typeid_itanium_cxx_abi.rs
index 9d1b92e1068..1a1aed61fed 100644
--- a/compiler/rustc_symbol_mangling/src/typeid/typeid_itanium_cxx_abi.rs
+++ b/compiler/rustc_symbol_mangling/src/typeid/typeid_itanium_cxx_abi.rs
@@ -261,12 +261,7 @@ fn encode_predicates<'tcx>(
 }
 
 /// Encodes a region using the Itanium C++ ABI as a vendor extended type.
-fn encode_region<'tcx>(
-    _tcx: TyCtxt<'tcx>,
-    region: Region<'tcx>,
-    dict: &mut FxHashMap<DictKey<'tcx>, usize>,
-    _options: EncodeTyOptions,
-) -> String {
+fn encode_region<'tcx>(region: Region<'tcx>, dict: &mut FxHashMap<DictKey<'tcx>, usize>) -> String {
     // u6region[I[<region-disambiguator>][<region-index>]E] as vendor extended type
     let mut s = String::new();
     match region.kind() {
@@ -314,7 +309,7 @@ fn encode_args<'tcx>(
         for arg in args {
             match arg.unpack() {
                 GenericArgKind::Lifetime(region) => {
-                    s.push_str(&encode_region(tcx, region, dict, options));
+                    s.push_str(&encode_region(region, dict));
                 }
                 GenericArgKind::Type(ty) => {
                     s.push_str(&encode_ty(tcx, ty, dict, options));
@@ -703,7 +698,7 @@ fn encode_ty<'tcx>(
                 ty::DynStar => "u7dynstarI",
             });
             s.push_str(&encode_predicates(tcx, predicates, dict, options));
-            s.push_str(&encode_region(tcx, *region, dict, options));
+            s.push_str(&encode_region(*region, dict));
             s.push('E');
             compress(dict, DictKey::Ty(ty, TyQ::None), &mut s);
             typeid.push_str(&s);
@@ -735,7 +730,6 @@ fn encode_ty<'tcx>(
 fn transform_predicates<'tcx>(
     tcx: TyCtxt<'tcx>,
     predicates: &List<ty::PolyExistentialPredicate<'tcx>>,
-    _options: EncodeTyOptions,
 ) -> &'tcx List<ty::PolyExistentialPredicate<'tcx>> {
     let predicates: Vec<ty::PolyExistentialPredicate<'tcx>> = predicates
         .iter()
@@ -967,7 +961,7 @@ fn transform_ty<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, options: TransformTyOptio
         ty::Dynamic(predicates, _region, kind) => {
             ty = Ty::new_dynamic(
                 tcx,
-                transform_predicates(tcx, predicates, options),
+                transform_predicates(tcx, predicates),
                 tcx.lifetimes.re_erased,
                 *kind,
             );
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 7d14395850b..05c141ab2d3 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
@@ -615,8 +615,6 @@ fn report_selection_error(
 
                         let UnsatisfiedConst(unsatisfied_const) = self
                             .maybe_add_note_for_unsatisfied_const(
-                                &obligation,
-                                trait_ref,
                                 &trait_predicate,
                                 &mut err,
                                 span,
@@ -1480,8 +1478,6 @@ fn add_help_message_for_fn_trait(
 
     fn maybe_add_note_for_unsatisfied_const(
         &self,
-        obligation: &PredicateObligation<'tcx>,
-        trait_ref: ty::PolyTraitRef<'tcx>,
         trait_predicate: &ty::PolyTraitPredicate<'tcx>,
         err: &mut Diagnostic,
         span: Span,
@@ -3359,8 +3355,6 @@ fn add_help_message_for_fn_trait(
 
     fn maybe_add_note_for_unsatisfied_const(
         &self,
-        _obligation: &PredicateObligation<'tcx>,
-        _trait_ref: ty::PolyTraitRef<'tcx>,
         _trait_predicate: &ty::PolyTraitPredicate<'tcx>,
         _err: &mut Diagnostic,
         _span: Span,