rustc_incremental: fix compilation

Author: flodiebold

src/librustc_incremental/assert_dep_graph.rs

@@ -174,6 +174,8 @@ impl<'a, 'tcx> ItemLikeVisitor<'tcx> for IfThisChanged<'a, 'tcx> {
     fn visit_impl_item(&mut self, impl_item: &'tcx hir::ImplItem) {
         self.process_attrs(impl_item.id, &impl_item.attrs);
     }
+
+    fn visit_expr_id(&mut self, _: hir::ExprId) { }
 }
 
 fn check_paths<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,

src/librustc_incremental/calculate_svh/mod.rs

@@ -226,5 +226,7 @@ impl<'a, 'tcx> Visitor<'tcx> for HashItemsVisitor<'a, 'tcx> {
         self.calculate_node_id(item.id, |v| v.visit_foreign_item(item));
         visit::walk_foreign_item(self, item);
     }
+
+    fn visit_expr_id(&mut self, _: hir::ExprId) { }
 }
 

src/librustc_incremental/calculate_svh/svh_visitor.rs

@@ -509,6 +509,10 @@ macro_rules! hash_span {
 }
 
 impl<'a, 'hash, 'tcx> visit::Visitor<'tcx> for StrictVersionHashVisitor<'a, 'hash, 'tcx> {
+    fn visit_expr_id(&mut self, _: hir::ExprId) {
+        // Body exprs are hashed independently
+    }
+
     fn visit_variant_data(&mut self,
                           s: &'tcx VariantData,
                           name: Name,

src/librustc_incremental/persist/dirty_clean.rs

@@ -185,6 +185,8 @@ impl<'a, 'tcx> ItemLikeVisitor<'tcx> for DirtyCleanVisitor<'a, 'tcx> {
 
     fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {
     }
+
+    fn visit_expr_id(&mut self, _: hir::ExprId) { }
 }
 
 pub fn check_dirty_clean_metadata<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
@@ -229,6 +231,8 @@ impl<'a, 'tcx, 'm> ItemLikeVisitor<'tcx> for DirtyCleanMetadataVisitor<'a, 'tcx,
 
     fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {
     }
+
+    fn visit_expr_id(&mut self, _: hir::ExprId) { }
 }
 
 impl<'a, 'tcx, 'm> DirtyCleanMetadataVisitor<'a, 'tcx, 'm> {