3 files changed, 12 insertions, 13 deletions
diff --git a/compiler/rustc_resolve/src/build_reduced_graph.rs b/compiler/rustc_resolve/src/build_reduced_graph.rs
index 4173e0fbf56..3cf9d324a38 100644
--- a/compiler/rustc_resolve/src/build_reduced_graph.rs
+++ b/compiler/rustc_resolve/src/build_reduced_graph.rs
@@ -1194,15 +1194,9 @@ impl<'a, 'b> BuildReducedGraphVisitor<'a, 'b> {
     // Mark the given macro as unused unless its name starts with `_`.
     // Macro uses will remove items from this set, and the remaining
     // items will be reported as `unused_macros`.
-    fn insert_unused_macro(
-        &mut self,
-        ident: Ident,
-        def_id: LocalDefId,
-        node_id: NodeId,
-        span: Span,
-    ) {
+    fn insert_unused_macro(&mut self, ident: Ident, def_id: LocalDefId, node_id: NodeId) {
         if !ident.as_str().starts_with('_') {
-            self.r.unused_macros.insert(def_id, (node_id, span));
+            self.r.unused_macros.insert(def_id, (node_id, ident));
         }
     }
 
@@ -1246,7 +1240,7 @@ impl<'a, 'b> BuildReducedGraphVisitor<'a, 'b> {
                 self.r.define(module, ident, MacroNS, (res, vis, span, expansion, IsMacroExport));
             } else {
                 self.r.check_reserved_macro_name(ident, res);
-                self.insert_unused_macro(ident, def_id, item.id, span);
+                self.insert_unused_macro(ident, def_id, item.id);
             }
             self.r.visibilities.insert(def_id, vis);
             self.r.arenas.alloc_macro_rules_scope(MacroRulesScope::Binding(
@@ -1267,7 +1261,7 @@ impl<'a, 'b> BuildReducedGraphVisitor<'a, 'b> {
                 _ => self.resolve_visibility(&item.vis),
             };
             if vis != ty::Visibility::Public {
-                self.insert_unused_macro(ident, def_id, item.id, span);
+                self.insert_unused_macro(ident, def_id, item.id);
             }
             self.r.define(module, ident, MacroNS, (res, vis, span, expansion));
             self.r.visibilities.insert(def_id, vis);
diff --git a/compiler/rustc_resolve/src/lib.rs b/compiler/rustc_resolve/src/lib.rs
index 5f3620b247e..f5bea83bdcf 100644
--- a/compiler/rustc_resolve/src/lib.rs
+++ b/compiler/rustc_resolve/src/lib.rs
@@ -988,7 +988,7 @@ pub struct Resolver<'a> {
     non_macro_attr: Lrc<SyntaxExtension>,
     local_macro_def_scopes: FxHashMap<LocalDefId, Module<'a>>,
     ast_transform_scopes: FxHashMap<LocalExpnId, Module<'a>>,
-    unused_macros: FxHashMap<LocalDefId, (NodeId, Span)>,
+    unused_macros: FxHashMap<LocalDefId, (NodeId, Ident)>,
     proc_macro_stubs: FxHashSet<LocalDefId>,
     /// Traces collected during macro resolution and validated when it's complete.
     single_segment_macro_resolutions:
diff --git a/compiler/rustc_resolve/src/macros.rs b/compiler/rustc_resolve/src/macros.rs
index 4f6e23d8f84..31fd9b989e1 100644
--- a/compiler/rustc_resolve/src/macros.rs
+++ b/compiler/rustc_resolve/src/macros.rs
@@ -315,8 +315,13 @@ impl<'a> ResolverExpand for Resolver<'a> {
     }
 
     fn check_unused_macros(&mut self) {
-        for (_, &(node_id, span)) in self.unused_macros.iter() {
-            self.lint_buffer.buffer_lint(UNUSED_MACROS, node_id, span, "unused macro definition");
+        for (_, &(node_id, ident)) in self.unused_macros.iter() {
+            self.lint_buffer.buffer_lint(
+                UNUSED_MACROS,
+                node_id,
+                ident.span,
+                &format!("unused macro definition: `{}`", ident.as_str()),
+            );
         }
     }