Remove usage of DUMMY_HIR_ID in some visitors

src/librustc_lint/builtin.rs

@@ -1354,7 +1354,7 @@ declare_lint! {
 }
 
 pub struct UnnameableTestItems {
-    boundary: hir::HirId, // HirId of the item under which things are not nameable
+    boundary: Option<hir::HirId>, // HirId of the item under which things are not nameable
     items_nameable: bool,
 }
 
@@ -1362,7 +1362,7 @@ impl_lint_pass!(UnnameableTestItems => [UNNAMEABLE_TEST_ITEMS]);
 
 impl UnnameableTestItems {
     pub fn new() -> Self {
-        Self { boundary: hir::DUMMY_HIR_ID, items_nameable: true }
+        Self { boundary: None, items_nameable: true }
     }
 }
 
@@ -1372,7 +1372,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for UnnameableTestItems {
             if let hir::ItemKind::Mod(..) = it.kind {
             } else {
                 self.items_nameable = false;
-                self.boundary = it.hir_id;
+                self.boundary = Some(it.hir_id);
             }
             return;
         }
@@ -1385,7 +1385,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for UnnameableTestItems {
     }
 
     fn check_item_post(&mut self, _cx: &LateContext<'_, '_>, it: &hir::Item<'_>) {
-        if !self.items_nameable && self.boundary == it.hir_id {
+        if !self.items_nameable && self.boundary == Some(it.hir_id) {
             self.items_nameable = true;
         }
     }

src/librustc_lint/types.rs

@@ -43,14 +43,14 @@ declare_lint! {
 #[derive(Copy, Clone)]
 pub struct TypeLimits {
     /// Id of the last visited negated expression
-    negated_expr_id: hir::HirId,
+    negated_expr_id: Option<hir::HirId>,
 }
 
 impl_lint_pass!(TypeLimits => [UNUSED_COMPARISONS, OVERFLOWING_LITERALS]);
 
 impl TypeLimits {
     pub fn new() -> TypeLimits {
-        TypeLimits { negated_expr_id: hir::DUMMY_HIR_ID }
+        TypeLimits { negated_expr_id: None }
     }
 }
 
@@ -244,7 +244,7 @@ fn lint_int_literal<'a, 'tcx>(
     let int_type = t.normalize(cx.sess().target.ptr_width);
     let (min, max) = int_ty_range(int_type);
     let max = max as u128;
-    let negative = type_limits.negated_expr_id == e.hir_id;
+    let negative = type_limits.negated_expr_id == Some(e.hir_id);
 
     // Detect literal value out of range [min, max] inclusive
     // avoiding use of -min to prevent overflow/panic
@@ -397,8 +397,8 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for TypeLimits {
         match e.kind {
             hir::ExprKind::Unary(hir::UnOp::UnNeg, ref expr) => {
                 // propagate negation, if the negation itself isn't negated
-                if self.negated_expr_id != e.hir_id {
-                    self.negated_expr_id = expr.hir_id;
+                if self.negated_expr_id != Some(e.hir_id) {
+                    self.negated_expr_id = Some(expr.hir_id);
                 }
             }
             hir::ExprKind::Binary(binop, ref l, ref r) => {

src/librustc_privacy/lib.rs

@@ -1012,7 +1012,7 @@ impl DefIdVisitor<'tcx> for ReachEverythingInTheInterfaceVisitor<'_, 'tcx> {
 struct NamePrivacyVisitor<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
     tables: &'a ty::TypeckTables<'tcx>,
-    current_item: hir::HirId,
+    current_item: Option<hir::HirId>,
     empty_tables: &'a ty::TypeckTables<'tcx>,
 }
 
@@ -1028,7 +1028,7 @@ impl<'a, 'tcx> NamePrivacyVisitor<'a, 'tcx> {
     ) {
         // definition of the field
         let ident = Ident::new(kw::Invalid, use_ctxt);
-        let current_hir = self.current_item;
+        let current_hir = self.current_item.unwrap();
         let def_id = self.tcx.adjust_ident_and_get_scope(ident, def.did, current_hir).1;
         if !def.is_enum() && !field.vis.is_accessible_from(def_id, self.tcx) {
             let label = if in_update_syntax {
@@ -1074,7 +1074,7 @@ impl<'a, 'tcx> Visitor<'tcx> for NamePrivacyVisitor<'a, 'tcx> {
     }
 
     fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
-        let orig_current_item = mem::replace(&mut self.current_item, item.hir_id);
+        let orig_current_item = mem::replace(&mut self.current_item, Some(item.hir_id));
         let orig_tables =
             mem::replace(&mut self.tables, item_tables(self.tcx, item.hir_id, self.empty_tables));
         intravisit::walk_item(self, item);
@@ -2059,7 +2059,7 @@ fn check_mod_privacy(tcx: TyCtxt<'_>, module_def_id: DefId) {
     let mut visitor = NamePrivacyVisitor {
         tcx,
         tables: &empty_tables,
-        current_item: hir::DUMMY_HIR_ID,
+        current_item: None,
         empty_tables: &empty_tables,
     };
     let (module, span, hir_id) = tcx.hir().get_module(module_def_id);