Auto merge of #101709 - nnethercote:simplify-visitors-more, r=cjgillot

Simplify visitors more

A successor to #100392.

r? `@cjgillot`

compiler/rustc_ast/src/visit.rs

@@ -156,8 +156,8 @@ pub trait Visitor<'ast>: Sized {
     fn visit_where_predicate(&mut self, p: &'ast WherePredicate) {
         walk_where_predicate(self, p)
     }
-    fn visit_fn(&mut self, fk: FnKind<'ast>, s: Span, _: NodeId) {
+    fn visit_fn(&mut self, fk: FnKind<'ast>, _: Span, _: NodeId) {
-        walk_fn(self, fk, s)
+        walk_fn(self, fk)
     }
     fn visit_assoc_item(&mut self, i: &'ast AssocItem, ctxt: AssocCtxt) {
         walk_assoc_item(self, i, ctxt)
@@ -201,11 +201,11 @@ pub trait Visitor<'ast>: Sized {
     fn visit_use_tree(&mut self, use_tree: &'ast UseTree, id: NodeId, _nested: bool) {
         walk_use_tree(self, use_tree, id)
     }
-    fn visit_path_segment(&mut self, path_span: Span, path_segment: &'ast PathSegment) {
+    fn visit_path_segment(&mut self, path_segment: &'ast PathSegment) {
-        walk_path_segment(self, path_span, path_segment)
+        walk_path_segment(self, path_segment)
     }
-    fn visit_generic_args(&mut self, path_span: Span, generic_args: &'ast GenericArgs) {
+    fn visit_generic_args(&mut self, generic_args: &'ast GenericArgs) {
-        walk_generic_args(self, path_span, generic_args)
+        walk_generic_args(self, generic_args)
     }
     fn visit_generic_arg(&mut self, generic_arg: &'ast GenericArg) {
         walk_generic_arg(self, generic_arg)
@@ -435,7 +435,7 @@ pub fn walk_ty<'a, V: Visitor<'a>>(visitor: &mut V, typ: &'a Ty) {
 
 pub fn walk_path<'a, V: Visitor<'a>>(visitor: &mut V, path: &'a Path) {
     for segment in &path.segments {
-        visitor.visit_path_segment(path.span, segment);
+        visitor.visit_path_segment(segment);
     }
 }
 
@@ -457,18 +457,14 @@ pub fn walk_use_tree<'a, V: Visitor<'a>>(visitor: &mut V, use_tree: &'a UseTree,
     }
 }
 
-pub fn walk_path_segment<'a, V: Visitor<'a>>(
+pub fn walk_path_segment<'a, V: Visitor<'a>>(visitor: &mut V, segment: &'a PathSegment) {
-    visitor: &mut V,
-    path_span: Span,
-    segment: &'a PathSegment,
-) {
     visitor.visit_ident(segment.ident);
     if let Some(ref args) = segment.args {
-        visitor.visit_generic_args(path_span, args);
+        visitor.visit_generic_args(args);
     }
 }
 
-pub fn walk_generic_args<'a, V>(visitor: &mut V, _path_span: Span, generic_args: &'a GenericArgs)
+pub fn walk_generic_args<'a, V>(visitor: &mut V, generic_args: &'a GenericArgs)
 where
     V: Visitor<'a>,
 {
@@ -502,7 +498,7 @@ where
 pub fn walk_assoc_constraint<'a, V: Visitor<'a>>(visitor: &mut V, constraint: &'a AssocConstraint) {
     visitor.visit_ident(constraint.ident);
     if let Some(ref gen_args) = constraint.gen_args {
-        visitor.visit_generic_args(gen_args.span(), gen_args);
+        visitor.visit_generic_args(gen_args);
     }
     match constraint.kind {
         AssocConstraintKind::Equality { ref term } => match term {
@@ -659,7 +655,7 @@ pub fn walk_fn_decl<'a, V: Visitor<'a>>(visitor: &mut V, function_declaration: &
     visitor.visit_fn_ret_ty(&function_declaration.output);
 }
 
-pub fn walk_fn<'a, V: Visitor<'a>>(visitor: &mut V, kind: FnKind<'a>, _span: Span) {
+pub fn walk_fn<'a, V: Visitor<'a>>(visitor: &mut V, kind: FnKind<'a>) {
     match kind {
         FnKind::Fn(_, _, sig, _, generics, body) => {
             visitor.visit_generics(generics);
@@ -800,7 +796,7 @@ pub fn walk_expr<'a, V: Visitor<'a>>(visitor: &mut V, expression: &'a Expr) {
             walk_list!(visitor, visit_expr, arguments);
         }
         ExprKind::MethodCall(ref segment, ref receiver, ref arguments, _span) => {
-            visitor.visit_path_segment(expression.span, segment);
+            visitor.visit_path_segment(segment);
             visitor.visit_expr(receiver);
             walk_list!(visitor, visit_expr, arguments);
         }

compiler/rustc_ast_lowering/src/index.rs

@@ -246,9 +246,9 @@ impl<'a, 'hir> Visitor<'hir> for NodeCollector<'a, 'hir> {
         });
     }
 
-    fn visit_path_segment(&mut self, path_span: Span, path_segment: &'hir PathSegment<'hir>) {
+    fn visit_path_segment(&mut self, path_segment: &'hir PathSegment<'hir>) {
-        self.insert(path_span, path_segment.hir_id, Node::PathSegment(path_segment));
+        self.insert(path_segment.ident.span, path_segment.hir_id, Node::PathSegment(path_segment));
-        intravisit::walk_path_segment(self, path_span, path_segment);
+        intravisit::walk_path_segment(self, path_segment);
     }
 
     fn visit_ty(&mut self, ty: &'hir Ty<'hir>) {
@@ -280,12 +280,12 @@ impl<'a, 'hir> Visitor<'hir> for NodeCollector<'a, 'hir> {
         fk: intravisit::FnKind<'hir>,
         fd: &'hir FnDecl<'hir>,
         b: BodyId,
-        s: Span,
+        _: Span,
         id: HirId,
     ) {
         assert_eq!(self.owner, id.owner);
         assert_eq!(self.parent_node, id.local_id);
-        intravisit::walk_fn(self, fk, fd, b, s, id);
+        intravisit::walk_fn(self, fk, fd, b, id);
     }
 
     fn visit_block(&mut self, block: &'hir Block<'hir>) {

compiler/rustc_ast_lowering/src/lifetime_collector.rs

@@ -63,9 +63,9 @@ impl<'ast> Visitor<'ast> for LifetimeCollectVisitor<'ast> {
         self.record_lifetime_use(*lifetime);
     }
 
-    fn visit_path_segment(&mut self, path_span: Span, path_segment: &'ast PathSegment) {
+    fn visit_path_segment(&mut self, path_segment: &'ast PathSegment) {
-        self.record_elided_anchor(path_segment.id, path_span);
+        self.record_elided_anchor(path_segment.id, path_segment.ident.span);
-        visit::walk_path_segment(self, path_span, path_segment);
+        visit::walk_path_segment(self, path_segment);
     }
 
     fn visit_poly_trait_ref(&mut self, t: &'ast PolyTraitRef) {

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -223,11 +223,9 @@ impl<'a> AstValidator<'a> {
                 for (i, segment) in path.segments.iter().enumerate() {
                     // Allow `impl Trait` iff we're on the final path segment
                     if i == path.segments.len() - 1 {
-                        self.visit_path_segment(path.span, segment);
+                        self.visit_path_segment(segment);
                     } else {
-                        self.with_banned_impl_trait(|this| {
+                        self.with_banned_impl_trait(|this| this.visit_path_segment(segment));
-                            this.visit_path_segment(path.span, segment)
-                        });
                     }
                 }
             }
@@ -1293,7 +1291,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
     }
 
     // Mirrors `visit::walk_generic_args`, but tracks relevant state.
-    fn visit_generic_args(&mut self, _: Span, generic_args: &'a GenericArgs) {
+    fn visit_generic_args(&mut self, generic_args: &'a GenericArgs) {
         match *generic_args {
             GenericArgs::AngleBracketed(ref data) => {
                 self.check_generic_args_before_constraints(data);
@@ -1529,7 +1527,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
             matches!(fk.header(), Some(FnHeader { constness: Const::Yes(_), .. }))
                 || matches!(fk.ctxt(), Some(FnCtxt::Assoc(_)));
 
-        self.with_tilde_const(tilde_const_allowed, |this| visit::walk_fn(this, fk, span));
+        self.with_tilde_const(tilde_const_allowed, |this| visit::walk_fn(this, fk));
     }
 
     fn visit_assoc_item(&mut self, item: &'a AssocItem, ctxt: AssocCtxt) {

compiler/rustc_ast_passes/src/feature_gate.rs

@@ -680,7 +680,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
             gate_feature_post!(&self, c_variadic, span, "C-variadic functions are unstable");
         }
 
-        visit::walk_fn(self, fn_kind, span)
+        visit::walk_fn(self, fn_kind)
     }
 
     fn visit_assoc_constraint(&mut self, constraint: &'a AssocConstraint) {

compiler/rustc_ast_passes/src/node_count.rs

@@ -63,9 +63,9 @@ impl<'ast> Visitor<'ast> for NodeCounter {
         self.count += 1;
         walk_generics(self, g)
     }
-    fn visit_fn(&mut self, fk: visit::FnKind<'_>, s: Span, _: NodeId) {
+    fn visit_fn(&mut self, fk: visit::FnKind<'_>, _: Span, _: NodeId) {
         self.count += 1;
-        walk_fn(self, fk, s)
+        walk_fn(self, fk)
     }
     fn visit_assoc_item(&mut self, ti: &AssocItem, ctxt: AssocCtxt) {
         self.count += 1;
@@ -115,9 +115,9 @@ impl<'ast> Visitor<'ast> for NodeCounter {
         self.count += 1;
         walk_use_tree(self, use_tree, id)
     }
-    fn visit_generic_args(&mut self, path_span: Span, generic_args: &GenericArgs) {
+    fn visit_generic_args(&mut self, generic_args: &GenericArgs) {
         self.count += 1;
-        walk_generic_args(self, path_span, generic_args)
+        walk_generic_args(self, generic_args)
     }
     fn visit_assoc_constraint(&mut self, constraint: &AssocConstraint) {
         self.count += 1;

compiler/rustc_hir/src/intravisit.rs

@@ -298,7 +298,7 @@ pub trait Visitor<'v>: Sized {
     fn visit_id(&mut self, _hir_id: HirId) {
         // Nothing to do.
     }
-    fn visit_name(&mut self, _span: Span, _name: Symbol) {
+    fn visit_name(&mut self, _name: Symbol) {
         // Nothing to do.
     }
     fn visit_ident(&mut self, ident: Ident) {
@@ -361,8 +361,8 @@ pub trait Visitor<'v>: Sized {
     fn visit_fn_decl(&mut self, fd: &'v FnDecl<'v>) {
         walk_fn_decl(self, fd)
     }
-    fn visit_fn(&mut self, fk: FnKind<'v>, fd: &'v FnDecl<'v>, b: BodyId, s: Span, id: HirId) {
+    fn visit_fn(&mut self, fk: FnKind<'v>, fd: &'v FnDecl<'v>, b: BodyId, _: Span, id: HirId) {
-        walk_fn(self, fk, fd, b, s, id)
+        walk_fn(self, fk, fd, b, id)
     }
     fn visit_use(&mut self, path: &'v Path<'v>, hir_id: HirId) {
         walk_use(self, path, hir_id)
@@ -388,8 +388,8 @@ pub trait Visitor<'v>: Sized {
     fn visit_param_bound(&mut self, bounds: &'v GenericBound<'v>) {
         walk_param_bound(self, bounds)
     }
-    fn visit_poly_trait_ref(&mut self, t: &'v PolyTraitRef<'v>, m: TraitBoundModifier) {
+    fn visit_poly_trait_ref(&mut self, t: &'v PolyTraitRef<'v>) {
-        walk_poly_trait_ref(self, t, m)
+        walk_poly_trait_ref(self, t)
     }
     fn visit_variant_data(&mut self, s: &'v VariantData<'v>) {
         walk_struct_def(self, s)
@@ -420,17 +420,18 @@ pub trait Visitor<'v>: Sized {
     fn visit_lifetime(&mut self, lifetime: &'v Lifetime) {
         walk_lifetime(self, lifetime)
     }
-    fn visit_qpath(&mut self, qpath: &'v QPath<'v>, id: HirId, span: Span) {
+    // The span is that of the surrounding type/pattern/expr/whatever.
-        walk_qpath(self, qpath, id, span)
+    fn visit_qpath(&mut self, qpath: &'v QPath<'v>, id: HirId, _span: Span) {
+        walk_qpath(self, qpath, id)
     }
     fn visit_path(&mut self, path: &'v Path<'v>, _id: HirId) {
         walk_path(self, path)
     }
-    fn visit_path_segment(&mut self, path_span: Span, path_segment: &'v PathSegment<'v>) {
+    fn visit_path_segment(&mut self, path_segment: &'v PathSegment<'v>) {
-        walk_path_segment(self, path_span, path_segment)
+        walk_path_segment(self, path_segment)
     }
-    fn visit_generic_args(&mut self, path_span: Span, generic_args: &'v GenericArgs<'v>) {
+    fn visit_generic_args(&mut self, generic_args: &'v GenericArgs<'v>) {
-        walk_generic_args(self, path_span, generic_args)
+        walk_generic_args(self, generic_args)
     }
     fn visit_assoc_type_binding(&mut self, type_binding: &'v TypeBinding<'v>) {
         walk_assoc_type_binding(self, type_binding)
@@ -472,7 +473,7 @@ pub fn walk_local<'v, V: Visitor<'v>>(visitor: &mut V, local: &'v Local<'v>) {
 }
 
 pub fn walk_ident<'v, V: Visitor<'v>>(visitor: &mut V, ident: Ident) {
-    visitor.visit_name(ident.span, ident.name);
+    visitor.visit_name(ident.name);
 }
 
 pub fn walk_label<'v, V: Visitor<'v>>(visitor: &mut V, label: &'v Label) {
@@ -494,11 +495,7 @@ pub fn walk_lifetime<'v, V: Visitor<'v>>(visitor: &mut V, lifetime: &'v Lifetime
     }
 }
 
-pub fn walk_poly_trait_ref<'v, V: Visitor<'v>>(
+pub fn walk_poly_trait_ref<'v, V: Visitor<'v>>(visitor: &mut V, trait_ref: &'v PolyTraitRef<'v>) {
-    visitor: &mut V,
-    trait_ref: &'v PolyTraitRef<'v>,
-    _modifier: TraitBoundModifier,
-) {
     walk_list!(visitor, visit_generic_param, trait_ref.bound_generic_params);
     visitor.visit_trait_ref(&trait_ref.trait_ref);
 }
@@ -519,7 +516,7 @@ pub fn walk_item<'v, V: Visitor<'v>>(visitor: &mut V, item: &'v Item<'v>) {
         ItemKind::ExternCrate(orig_name) => {
             visitor.visit_id(item.hir_id());
             if let Some(orig_name) = orig_name {
-                visitor.visit_name(item.span, orig_name);
+                visitor.visit_name(orig_name);
             }
         }
         ItemKind::Use(ref path, _) => {
@@ -680,7 +677,7 @@ pub fn walk_ty<'v, V: Visitor<'v>>(visitor: &mut V, typ: &'v Ty<'v>) {
         }
         TyKind::TraitObject(bounds, ref lifetime, _syntax) => {
             for bound in bounds {
-                visitor.visit_poly_trait_ref(bound, TraitBoundModifier::None);
+                visitor.visit_poly_trait_ref(bound);
             }
             visitor.visit_lifetime(lifetime);
         }
@@ -693,12 +690,7 @@ pub fn walk_inf<'v, V: Visitor<'v>>(visitor: &mut V, inf: &'v InferArg) {
     visitor.visit_id(inf.hir_id);
 }
 
-pub fn walk_qpath<'v, V: Visitor<'v>>(
+pub fn walk_qpath<'v, V: Visitor<'v>>(visitor: &mut V, qpath: &'v QPath<'v>, id: HirId) {
-    visitor: &mut V,
-    qpath: &'v QPath<'v>,
-    id: HirId,
-    span: Span,
-) {
     match *qpath {
         QPath::Resolved(ref maybe_qself, ref path) => {
             walk_list!(visitor, visit_ty, maybe_qself);
@@ -706,7 +698,7 @@ pub fn walk_qpath<'v, V: Visitor<'v>>(
         }
         QPath::TypeRelative(ref qself, ref segment) => {
             visitor.visit_ty(qself);
-            visitor.visit_path_segment(span, segment);
+            visitor.visit_path_segment(segment);
         }
         QPath::LangItem(..) => {}
     }
@@ -714,27 +706,19 @@ pub fn walk_qpath<'v, V: Visitor<'v>>(
 
 pub fn walk_path<'v, V: Visitor<'v>>(visitor: &mut V, path: &'v Path<'v>) {
     for segment in path.segments {
-        visitor.visit_path_segment(path.span, segment);
+        visitor.visit_path_segment(segment);
     }
 }
 
-pub fn walk_path_segment<'v, V: Visitor<'v>>(
+pub fn walk_path_segment<'v, V: Visitor<'v>>(visitor: &mut V, segment: &'v PathSegment<'v>) {
-    visitor: &mut V,
-    path_span: Span,
-    segment: &'v PathSegment<'v>,
-) {
     visitor.visit_ident(segment.ident);
     visitor.visit_id(segment.hir_id);
     if let Some(ref args) = segment.args {
-        visitor.visit_generic_args(path_span, args);
+        visitor.visit_generic_args(args);
     }
 }
 
-pub fn walk_generic_args<'v, V: Visitor<'v>>(
+pub fn walk_generic_args<'v, V: Visitor<'v>>(visitor: &mut V, generic_args: &'v GenericArgs<'v>) {
-    visitor: &mut V,
-    _path_span: Span,
-    generic_args: &'v GenericArgs<'v>,
-) {
     walk_list!(visitor, visit_generic_arg, generic_args.args);
     walk_list!(visitor, visit_assoc_type_binding, generic_args.bindings);
 }
@@ -745,7 +729,7 @@ pub fn walk_assoc_type_binding<'v, V: Visitor<'v>>(
 ) {
     visitor.visit_id(type_binding.hir_id);
     visitor.visit_ident(type_binding.ident);
-    visitor.visit_generic_args(type_binding.span, type_binding.gen_args);
+    visitor.visit_generic_args(type_binding.gen_args);
     match type_binding.kind {
         TypeBindingKind::Equality { ref term } => match term {
             Term::Ty(ref ty) => visitor.visit_ty(ty),
@@ -819,12 +803,12 @@ pub fn walk_foreign_item<'v, V: Visitor<'v>>(visitor: &mut V, foreign_item: &'v
 
 pub fn walk_param_bound<'v, V: Visitor<'v>>(visitor: &mut V, bound: &'v GenericBound<'v>) {
     match *bound {
-        GenericBound::Trait(ref typ, modifier) => {
+        GenericBound::Trait(ref typ, _modifier) => {
-            visitor.visit_poly_trait_ref(typ, modifier);
+            visitor.visit_poly_trait_ref(typ);
         }
-        GenericBound::LangItemTrait(_, span, hir_id, args) => {
+        GenericBound::LangItemTrait(_, _span, hir_id, args) => {
             visitor.visit_id(hir_id);
-            visitor.visit_generic_args(span, args);
+            visitor.visit_generic_args(args);
         }
         GenericBound::Outlives(ref lifetime) => visitor.visit_lifetime(lifetime),
     }
@@ -910,7 +894,6 @@ pub fn walk_fn<'v, V: Visitor<'v>>(
     function_kind: FnKind<'v>,
     function_declaration: &'v FnDecl<'v>,
     body_id: BodyId,
-    _span: Span,
     id: HirId,
 ) {
     visitor.visit_id(id);
@@ -1095,7 +1078,7 @@ pub fn walk_expr<'v, V: Visitor<'v>>(visitor: &mut V, expression: &'v Expr<'v>)
             walk_list!(visitor, visit_expr, arguments);
         }
         ExprKind::MethodCall(ref segment, receiver, arguments, _) => {
-            visitor.visit_path_segment(expression.span, segment);
+            visitor.visit_path_segment(segment);
             visitor.visit_expr(receiver);
             walk_list!(visitor, visit_expr, arguments);
         }

compiler/rustc_infer/src/infer/error_reporting/nice_region_error/find_anon_type.rs

@@ -91,7 +91,7 @@ impl<'tcx> Visitor<'tcx> for FindNestedTypeVisitor<'tcx> {
             hir::TyKind::TraitObject(bounds, ..) => {
                 for bound in bounds {
                     self.current_index.shift_in(1);
-                    self.visit_poly_trait_ref(bound, hir::TraitBoundModifier::None);
+                    self.visit_poly_trait_ref(bound);
                     self.current_index.shift_out(1);
                 }
             }

compiler/rustc_lint/src/builtin.rs

@@ -1467,7 +1467,7 @@ impl TypeAliasBounds {
                 if TypeAliasBounds::is_type_variable_assoc(qpath) {
                     self.err.span_help(span, fluent::lint::builtin_type_alias_bounds_help);
                 }
-                intravisit::walk_qpath(self, qpath, id, span)
+                intravisit::walk_qpath(self, qpath, id)
             }
         }
 
@@ -2000,7 +2000,7 @@ impl KeywordIdents {
 }
 
 impl EarlyLintPass for KeywordIdents {
-    fn check_mac_def(&mut self, cx: &EarlyContext<'_>, mac_def: &ast::MacroDef, _id: ast::NodeId) {
+    fn check_mac_def(&mut self, cx: &EarlyContext<'_>, mac_def: &ast::MacroDef) {
         self.check_tokens(cx, mac_def.body.inner_tokens());
     }
     fn check_mac(&mut self, cx: &EarlyContext<'_>, mac: &ast::MacCall) {

compiler/rustc_lint/src/early.rs

@@ -147,7 +147,7 @@ impl<'a, T: EarlyLintPass> ast_visit::Visitor<'a> for EarlyContextAndPass<'a, T>
     fn visit_fn(&mut self, fk: ast_visit::FnKind<'a>, span: Span, id: ast::NodeId) {
         run_early_pass!(self, check_fn, fk, span, id);
         self.check_id(id);
-        ast_visit::walk_fn(self, fk, span);
+        ast_visit::walk_fn(self, fk);
 
         // Explicitly check for lints associated with 'closure_id', since
         // it does not have a corresponding AST node
@@ -266,9 +266,9 @@ impl<'a, T: EarlyLintPass> ast_visit::Visitor<'a> for EarlyContextAndPass<'a, T>
         ast_visit::walk_path(self, p);
     }
 
-    fn visit_path_segment(&mut self, path_span: Span, s: &'a ast::PathSegment) {
+    fn visit_path_segment(&mut self, s: &'a ast::PathSegment) {
         self.check_id(s.id);
-        ast_visit::walk_path_segment(self, path_span, s);
+        ast_visit::walk_path_segment(self, s);
     }
 
     fn visit_attribute(&mut self, attr: &'a ast::Attribute) {
@@ -276,7 +276,7 @@ impl<'a, T: EarlyLintPass> ast_visit::Visitor<'a> for EarlyContextAndPass<'a, T>
     }
 
     fn visit_mac_def(&mut self, mac: &'a ast::MacroDef, id: ast::NodeId) {
-        run_early_pass!(self, check_mac_def, mac, id);
+        run_early_pass!(self, check_mac_def, mac);
         self.check_id(id);
     }
 

compiler/rustc_lint/src/late.rs

@@ -76,8 +76,8 @@ impl<'tcx, T: LateLintPass<'tcx>> LateContextAndPass<'tcx, T> {
         self.context.param_env = old_param_env;
     }
 
-    fn process_mod(&mut self, m: &'tcx hir::Mod<'tcx>, s: Span, n: hir::HirId) {
+    fn process_mod(&mut self, m: &'tcx hir::Mod<'tcx>, n: hir::HirId) {
-        lint_callback!(self, check_mod, m, s, n);
+        lint_callback!(self, check_mod, m, n);
         hir_visit::walk_mod(self, m, n);
     }
 }
@@ -187,7 +187,7 @@ impl<'tcx, T: LateLintPass<'tcx>> hir_visit::Visitor<'tcx> for LateContextAndPas
         let old_cached_typeck_results = self.context.cached_typeck_results.take();
         let body = self.context.tcx.hir().body(body_id);
         lint_callback!(self, check_fn, fk, decl, body, span, id);
-        hir_visit::walk_fn(self, fk, decl, body_id, span, id);
+        hir_visit::walk_fn(self, fk, decl, body_id, id);
         self.context.enclosing_body = old_enclosing_body;
         self.context.cached_typeck_results.set(old_cached_typeck_results);
     }
@@ -220,9 +220,9 @@ impl<'tcx, T: LateLintPass<'tcx>> hir_visit::Visitor<'tcx> for LateContextAndPas
         hir_visit::walk_inf(self, inf);
     }
 
-    fn visit_mod(&mut self, m: &'tcx hir::Mod<'tcx>, s: Span, n: hir::HirId) {
+    fn visit_mod(&mut self, m: &'tcx hir::Mod<'tcx>, _: Span, n: hir::HirId) {
         if !self.context.only_module {
-            self.process_mod(m, s, n);
+            self.process_mod(m, n);
         }
     }
 
@@ -258,13 +258,9 @@ impl<'tcx, T: LateLintPass<'tcx>> hir_visit::Visitor<'tcx> for LateContextAndPas
         hir_visit::walk_where_predicate(self, p);
     }
 
-    fn visit_poly_trait_ref(
+    fn visit_poly_trait_ref(&mut self, t: &'tcx hir::PolyTraitRef<'tcx>) {
-        &mut self,
+        lint_callback!(self, check_poly_trait_ref, t);
-        t: &'tcx hir::PolyTraitRef<'tcx>,
+        hir_visit::walk_poly_trait_ref(self, t);
-        m: hir::TraitBoundModifier,
-    ) {
-        lint_callback!(self, check_poly_trait_ref, t, m);
-        hir_visit::walk_poly_trait_ref(self, t, m);
     }
 
     fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem<'tcx>) {
@@ -358,8 +354,8 @@ fn late_lint_mod_pass<'tcx, T: LateLintPass<'tcx>>(
 
     let mut cx = LateContextAndPass { context, pass };
 
-    let (module, span, hir_id) = tcx.hir().get_module(module_def_id);
+    let (module, _span, hir_id) = tcx.hir().get_module(module_def_id);
-    cx.process_mod(module, span, hir_id);
+    cx.process_mod(module, hir_id);
 
     // Visit the crate attributes
     if hir_id == hir::CRATE_HIR_ID {

compiler/rustc_lint/src/nonstandard_style.rs

@@ -327,13 +327,7 @@ impl NonSnakeCase {
 }
 
 impl<'tcx> LateLintPass<'tcx> for NonSnakeCase {
-    fn check_mod(
+    fn check_mod(&mut self, cx: &LateContext<'_>, _: &'tcx hir::Mod<'tcx>, id: hir::HirId) {
-        &mut self,
-        cx: &LateContext<'_>,
-        _: &'tcx hir::Mod<'tcx>,
-        _: Span,
-        id: hir::HirId,
-    ) {
         if id != hir::CRATE_HIR_ID {
             return;
         }

compiler/rustc_lint/src/passes.rs

@@ -16,7 +16,7 @@ macro_rules! late_lint_methods {
             fn check_body_post(a: &$hir hir::Body<$hir>);
             fn check_crate();
             fn check_crate_post();
-            fn check_mod(a: &$hir hir::Mod<$hir>, b: Span, c: hir::HirId);
+            fn check_mod(a: &$hir hir::Mod<$hir>, b: hir::HirId);
             fn check_foreign_item(a: &$hir hir::ForeignItem<$hir>);
             fn check_item(a: &$hir hir::Item<$hir>);
             fn check_item_post(a: &$hir hir::Item<$hir>);
@@ -31,7 +31,7 @@ macro_rules! late_lint_methods {
             fn check_ty(a: &$hir hir::Ty<$hir>);
             fn check_generic_param(a: &$hir hir::GenericParam<$hir>);
             fn check_generics(a: &$hir hir::Generics<$hir>);
-            fn check_poly_trait_ref(a: &$hir hir::PolyTraitRef<$hir>, b: hir::TraitBoundModifier);
+            fn check_poly_trait_ref(a: &$hir hir::PolyTraitRef<$hir>);
             fn check_fn(
                 a: rustc_hir::intravisit::FnKind<$hir>,
                 b: &$hir hir::FnDecl<$hir>,
@@ -162,7 +162,7 @@ macro_rules! early_lint_methods {
             fn check_impl_item(a: &ast::AssocItem);
             fn check_variant(a: &ast::Variant);
             fn check_attribute(a: &ast::Attribute);
-            fn check_mac_def(a: &ast::MacroDef, b: ast::NodeId);
+            fn check_mac_def(a: &ast::MacroDef);
             fn check_mac(a: &ast::MacCall);
 
             /// Called when entering a syntax node that can have lint attributes such

compiler/rustc_passes/src/hir_stats.rs

@@ -362,11 +362,11 @@ impl<'v> hir_visit::Visitor<'v> for StatCollector<'v> {
         fk: hir_visit::FnKind<'v>,
         fd: &'v hir::FnDecl<'v>,
         b: hir::BodyId,
-        s: Span,
+        _: Span,
         id: hir::HirId,
     ) {
         self.record("FnDecl", Id::None, fd);
-        hir_visit::walk_fn(self, fk, fd, b, s, id)
+        hir_visit::walk_fn(self, fk, fd, b, id)
     }
 
     fn visit_use(&mut self, p: &'v hir::Path<'v>, hir_id: hir::HirId) {
@@ -447,14 +447,14 @@ impl<'v> hir_visit::Visitor<'v> for StatCollector<'v> {
         hir_visit::walk_path(self, path)
     }
 
-    fn visit_path_segment(&mut self, path_span: Span, path_segment: &'v hir::PathSegment<'v>) {
+    fn visit_path_segment(&mut self, path_segment: &'v hir::PathSegment<'v>) {
         self.record("PathSegment", Id::None, path_segment);
-        hir_visit::walk_path_segment(self, path_span, path_segment)
+        hir_visit::walk_path_segment(self, path_segment)
     }
 
-    fn visit_generic_args(&mut self, sp: Span, ga: &'v hir::GenericArgs<'v>) {
+    fn visit_generic_args(&mut self, ga: &'v hir::GenericArgs<'v>) {
         self.record("GenericArgs", Id::None, ga);
-        hir_visit::walk_generic_args(self, sp, ga)
+        hir_visit::walk_generic_args(self, ga)
     }
 
     fn visit_assoc_type_binding(&mut self, type_binding: &'v hir::TypeBinding<'v>) {
@@ -612,9 +612,9 @@ impl<'v> ast_visit::Visitor<'v> for StatCollector<'v> {
         ast_visit::walk_where_predicate(self, p)
     }
 
-    fn visit_fn(&mut self, fk: ast_visit::FnKind<'v>, s: Span, _: NodeId) {
+    fn visit_fn(&mut self, fk: ast_visit::FnKind<'v>, _: Span, _: NodeId) {
         self.record("FnDecl", Id::None, fk.decl());
-        ast_visit::walk_fn(self, fk, s)
+        ast_visit::walk_fn(self, fk)
     }
 
     fn visit_assoc_item(&mut self, i: &'v ast::AssocItem, ctxt: ast_visit::AssocCtxt) {
@@ -652,21 +652,21 @@ impl<'v> ast_visit::Visitor<'v> for StatCollector<'v> {
     // one non-inline use (in `ast::Path::segments`). The latter case is more
     // common than the former case, so we implement this visitor and tolerate
     // the double counting in the former case.
-    fn visit_path_segment(&mut self, path_span: Span, path_segment: &'v ast::PathSegment) {
+    fn visit_path_segment(&mut self, path_segment: &'v ast::PathSegment) {
         self.record("PathSegment", Id::None, path_segment);
-        ast_visit::walk_path_segment(self, path_span, path_segment)
+        ast_visit::walk_path_segment(self, path_segment)
     }
 
     // `GenericArgs` has one inline use (in `ast::AssocConstraint::gen_args`) and one
     // non-inline use (in `ast::PathSegment::args`). The latter case is more
     // common, so we implement `visit_generic_args` and tolerate the double
     // counting in the former case.
-    fn visit_generic_args(&mut self, sp: Span, g: &'v ast::GenericArgs) {
+    fn visit_generic_args(&mut self, g: &'v ast::GenericArgs) {
         record_variants!(
             (self, g, g, Id::None, ast, GenericArgs, GenericArgs),
             [AngleBracketed, Parenthesized]
         );
-        ast_visit::walk_generic_args(self, sp, g)
+        ast_visit::walk_generic_args(self, g)
     }
 
     fn visit_attribute(&mut self, attr: &'v ast::Attribute) {

compiler/rustc_privacy/src/lib.rs

@@ -1314,7 +1314,7 @@ impl<'tcx> Visitor<'tcx> for TypePrivacyVisitor<'tcx> {
             }
         }
 
-        intravisit::walk_qpath(self, qpath, id, span);
+        intravisit::walk_qpath(self, qpath, id);
     }
 
     // Check types of patterns.

compiler/rustc_resolve/src/def_collector.rs

@@ -154,7 +154,7 @@ impl<'a, 'b> visit::Visitor<'a> for DefCollector<'a, 'b> {
             }
         }
 
-        visit::walk_fn(self, fn_kind, span);
+        visit::walk_fn(self, fn_kind);
     }
 
     fn visit_use_tree(&mut self, use_tree: &'a UseTree, id: NodeId, _nested: bool) {

compiler/rustc_resolve/src/late.rs

@@ -1030,7 +1030,7 @@ impl<'a: 'ast, 'ast> Visitor<'ast> for LateResolutionVisitor<'a, '_, 'ast> {
         if let Some(ref gen_args) = constraint.gen_args {
             // Forbid anonymous lifetimes in GAT parameters until proper semantics are decided.
             self.with_lifetime_rib(LifetimeRibKind::AnonymousReportError, |this| {
-                this.visit_generic_args(gen_args.span(), gen_args)
+                this.visit_generic_args(gen_args)
             });
         }
         match constraint.kind {
@@ -1044,10 +1044,10 @@ impl<'a: 'ast, 'ast> Visitor<'ast> for LateResolutionVisitor<'a, '_, 'ast> {
         }
     }
 
-    fn visit_path_segment(&mut self, path_span: Span, path_segment: &'ast PathSegment) {
+    fn visit_path_segment(&mut self, path_segment: &'ast PathSegment) {
         if let Some(ref args) = path_segment.args {
             match &**args {
-                GenericArgs::AngleBracketed(..) => visit::walk_generic_args(self, path_span, args),
+                GenericArgs::AngleBracketed(..) => visit::walk_generic_args(self, args),
                 GenericArgs::Parenthesized(p_args) => {
                     // Probe the lifetime ribs to know how to behave.
                     for rib in self.lifetime_ribs.iter().rev() {
@@ -1078,7 +1078,7 @@ impl<'a: 'ast, 'ast> Visitor<'ast> for LateResolutionVisitor<'a, '_, 'ast> {
                             // We have nowhere to introduce generics.  Code is malformed,
                             // so use regular lifetime resolution to avoid spurious errors.
                             LifetimeRibKind::Item | LifetimeRibKind::Generics { .. } => {
-                                visit::walk_generic_args(self, path_span, args);
+                                visit::walk_generic_args(self, args);
                                 break;
                             }
                             LifetimeRibKind::AnonymousCreateParameter { .. }
@@ -3798,7 +3798,7 @@ impl<'a: 'ast, 'b, 'ast> LateResolutionVisitor<'a, 'b, 'ast> {
                 for argument in arguments {
                     self.resolve_expr(argument, None);
                 }
-                self.visit_path_segment(expr.span, segment);
+                self.visit_path_segment(segment);
             }
 
             ExprKind::Call(ref callee, ref arguments) => {

compiler/rustc_resolve/src/late/lifetimes.rs

@@ -682,7 +682,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
                 let scope = Scope::TraitRefBoundary { s: self.scope };
                 self.with(scope, |this| {
                     for bound in bounds {
-                        this.visit_poly_trait_ref(bound, hir::TraitBoundModifier::None);
+                        this.visit_poly_trait_ref(bound);
                     }
                 });
                 match lifetime.name {
@@ -1105,11 +1105,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
         }
     }
 
-    fn visit_poly_trait_ref(
+    fn visit_poly_trait_ref(&mut self, trait_ref: &'tcx hir::PolyTraitRef<'tcx>) {
-        &mut self,
-        trait_ref: &'tcx hir::PolyTraitRef<'tcx>,
-        _modifier: hir::TraitBoundModifier,
-    ) {
         debug!("visit_poly_trait_ref(trait_ref={:?})", trait_ref);
 
         let (mut binders, scope_type) = self.poly_trait_ref_binder_info();
@@ -1827,7 +1823,7 @@ fn is_late_bound_map(tcx: TyCtxt<'_>, def_id: LocalDefId) -> Option<&FxIndexSet<
                     // is, those would be potentially inputs to
                     // projections
                     if let Some(last_segment) = path.segments.last() {
-                        self.visit_path_segment(path.span, last_segment);
+                        self.visit_path_segment(last_segment);
                     }
                 }
 

compiler/rustc_save_analysis/src/dump_visitor.rs

@@ -1306,7 +1306,7 @@ impl<'tcx> Visitor<'tcx> for DumpVisitor<'tcx> {
                 if let hir::QPath::Resolved(_, path) = path {
                     self.write_sub_paths_truncated(path);
                 }
-                intravisit::walk_qpath(self, path, t.hir_id, t.span);
+                intravisit::walk_qpath(self, path, t.hir_id);
             }
             hir::TyKind::Array(ref ty, ref length) => {
                 self.visit_ty(ty);

compiler/rustc_typeck/src/collect.rs

@@ -1346,16 +1346,12 @@ fn has_late_bound_regions<'tcx>(tcx: TyCtxt<'tcx>, node: Node<'tcx>) -> Option<S
             }
         }
 
-        fn visit_poly_trait_ref(
+        fn visit_poly_trait_ref(&mut self, tr: &'tcx hir::PolyTraitRef<'tcx>) {
-            &mut self,
-            tr: &'tcx hir::PolyTraitRef<'tcx>,
-            m: hir::TraitBoundModifier,
-        ) {
             if self.has_late_bound_regions.is_some() {
                 return;
             }
             self.outer_index.shift_in(1);
-            intravisit::walk_poly_trait_ref(self, tr, m);
+            intravisit::walk_poly_trait_ref(self, tr);
             self.outer_index.shift_out(1);
         }
 

src/tools/clippy/clippy_lints/src/derive.rs

@@ -425,7 +425,7 @@ struct UnsafeVisitor<'a, 'tcx> {
 impl<'tcx> Visitor<'tcx> for UnsafeVisitor<'_, 'tcx> {
     type NestedFilter = nested_filter::All;
 
-    fn visit_fn(&mut self, kind: FnKind<'tcx>, decl: &'tcx FnDecl<'_>, body_id: BodyId, span: Span, id: HirId) {
+    fn visit_fn(&mut self, kind: FnKind<'tcx>, decl: &'tcx FnDecl<'_>, body_id: BodyId, _: Span, id: HirId) {
         if self.has_unsafe {
             return;
         }
@@ -438,7 +438,7 @@ impl<'tcx> Visitor<'tcx> for UnsafeVisitor<'_, 'tcx> {
             }
         }
 
-        walk_fn(self, kind, decl, body_id, span, id);
+        walk_fn(self, kind, decl, body_id, id);
     }
 
     fn visit_expr(&mut self, expr: &'tcx Expr<'_>) {

src/tools/clippy/clippy_lints/src/disallowed_types.rs

@@ -2,7 +2,7 @@ use clippy_utils::diagnostics::span_lint_and_then;
 
 use rustc_data_structures::fx::FxHashMap;
 use rustc_hir::{
-    def::Res, def_id::DefId, Item, ItemKind, PolyTraitRef, PrimTy, TraitBoundModifier, Ty, TyKind, UseKind,
+    def::Res, def_id::DefId, Item, ItemKind, PolyTraitRef, PrimTy, Ty, TyKind, UseKind,
 };
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::{declare_tool_lint, impl_lint_pass};
@@ -120,7 +120,7 @@ impl<'tcx> LateLintPass<'tcx> for DisallowedTypes {
         }
     }
 
-    fn check_poly_trait_ref(&mut self, cx: &LateContext<'tcx>, poly: &'tcx PolyTraitRef<'tcx>, _: TraitBoundModifier) {
+    fn check_poly_trait_ref(&mut self, cx: &LateContext<'tcx>, poly: &'tcx PolyTraitRef<'tcx>) {
         self.check_res_emit(cx, &poly.trait_ref.path.res, poly.trait_ref.path.span);
     }
 }

src/tools/clippy/clippy_lints/src/lifetimes.rs

@@ -10,7 +10,7 @@ use rustc_hir::FnRetTy::Return;
 use rustc_hir::{
     BareFnTy, BodyId, FnDecl, GenericArg, GenericBound, GenericParam, GenericParamKind, Generics, Impl, ImplItem,
     ImplItemKind, Item, ItemKind, LangItem, Lifetime, LifetimeName, ParamName, PolyTraitRef, PredicateOrigin,
-    TraitBoundModifier, TraitFn, TraitItem, TraitItemKind, Ty, TyKind, WherePredicate,
+    TraitFn, TraitItem, TraitItemKind, Ty, TyKind, WherePredicate,
 };
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::hir::nested_filter as middle_nested_filter;
@@ -422,7 +422,7 @@ impl<'a, 'tcx> Visitor<'tcx> for RefVisitor<'a, 'tcx> {
         self.record(&Some(*lifetime));
     }
 
-    fn visit_poly_trait_ref(&mut self, poly_tref: &'tcx PolyTraitRef<'tcx>, tbm: TraitBoundModifier) {
+    fn visit_poly_trait_ref(&mut self, poly_tref: &'tcx PolyTraitRef<'tcx>) {
         let trait_ref = &poly_tref.trait_ref;
         if CLOSURE_TRAIT_BOUNDS.iter().any(|&item| {
             self.cx
@@ -435,7 +435,7 @@ impl<'a, 'tcx> Visitor<'tcx> for RefVisitor<'a, 'tcx> {
             sub_visitor.visit_trait_ref(trait_ref);
             self.nested_elision_site_lts.append(&mut sub_visitor.all_lts());
         } else {
-            walk_poly_trait_ref(self, poly_tref, tbm);
+            walk_poly_trait_ref(self, poly_tref);
         }
     }
 
@@ -466,7 +466,7 @@ impl<'a, 'tcx> Visitor<'tcx> for RefVisitor<'a, 'tcx> {
                     self.unelided_trait_object_lifetime = true;
                 }
                 for bound in bounds {
-                    self.visit_poly_trait_ref(bound, TraitBoundModifier::None);
+                    self.visit_poly_trait_ref(bound);
                 }
             },
             _ => walk_ty(self, ty),

src/tools/clippy/clippy_lints/src/unused_async.rs

@@ -70,7 +70,7 @@ impl<'tcx> LateLintPass<'tcx> for UnusedAsync {
     ) {
         if !span.from_expansion() && fn_kind.asyncness() == IsAsync::Async {
             let mut visitor = AsyncFnVisitor { cx, found_await: false };
-            walk_fn(&mut visitor, fn_kind, fn_decl, body.id(), span, hir_id);
+            walk_fn(&mut visitor, fn_kind, fn_decl, body.id(), hir_id);
             if !visitor.found_await {
                 span_lint_and_help(
                     cx,

src/tools/clippy/clippy_lints/src/unwrap.rs

@@ -326,6 +326,6 @@ impl<'tcx> LateLintPass<'tcx> for Unwrap {
             unwrappables: Vec::new(),
         };
 
-        walk_fn(&mut v, kind, decl, body.id(), span, fn_id);
+        walk_fn(&mut v, kind, decl, body.id(), fn_id);
     }
 }

src/tools/clippy/clippy_utils/src/lib.rs

@@ -1121,7 +1121,7 @@ pub struct ContainsName {
 }
 
 impl<'tcx> Visitor<'tcx> for ContainsName {
-    fn visit_name(&mut self, _: Span, name: Symbol) {
+    fn visit_name(&mut self, name: Symbol) {
         if self.name == name {
             self.result = true;
         }