Diagnostic for using macro_rules macro as attr/derive

2 files changed, 31 insertions, 3 deletions

diff --git a/compiler/rustc_resolve/src/diagnostics.rs b/compiler/rustc_resolve/src/diagnostics.rs
index 5437ca65935..7bcab3f1c43 100644
--- a/compiler/rustc_resolve/src/diagnostics.rs
+++ b/compiler/rustc_resolve/src/diagnostics.rs
@@ -35,7 +35,8 @@ use tracing::debug;
 
 use crate::errors::{
     self, AddedMacroUse, ChangeImportBinding, ChangeImportBindingSuggestion, ConsiderAddingADerive,
-    ExplicitUnsafeTraits, MacroDefinedLater, MacroSuggMovePosition, MaybeMissingMacroRulesName,
+    ExplicitUnsafeTraits, MacroDefinedLater, MacroRulesNot, MacroSuggMovePosition,
+    MaybeMissingMacroRulesName,
 };
 use crate::imports::{Import, ImportKind};
 use crate::late::{PatternSource, Rib};
@@ -1475,8 +1476,19 @@ impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
             let scope = self.local_macro_def_scopes[&def_id];
             let parent_nearest = parent_scope.module.nearest_parent_mod();
             if Some(parent_nearest) == scope.opt_def_id() {
-                err.subdiagnostic(MacroDefinedLater { span: unused_ident.span });
-                err.subdiagnostic(MacroSuggMovePosition { span: ident.span, ident });
+                match macro_kind {
+                    MacroKind::Bang => {
+                        err.subdiagnostic(MacroDefinedLater { span: unused_ident.span });
+                        err.subdiagnostic(MacroSuggMovePosition { span: ident.span, ident });
+                    }
+                    MacroKind::Attr => {
+                        err.subdiagnostic(MacroRulesNot::Attr { span: unused_ident.span, ident });
+                    }
+                    MacroKind::Derive => {
+                        err.subdiagnostic(MacroRulesNot::Derive { span: unused_ident.span, ident });
+                    }
+                }
+
                 return;
             }
         }
diff --git a/compiler/rustc_resolve/src/errors.rs b/compiler/rustc_resolve/src/errors.rs
index f605b7096f0..24f5a812a82 100644
--- a/compiler/rustc_resolve/src/errors.rs
+++ b/compiler/rustc_resolve/src/errors.rs
@@ -666,6 +666,22 @@ pub(crate) struct MacroSuggMovePosition {
 }
 
 #[derive(Subdiagnostic)]
+pub(crate) enum MacroRulesNot {
+    #[label(resolve_macro_cannot_use_as_attr)]
+    Attr {
+        #[primary_span]
+        span: Span,
+        ident: Ident,
+    },
+    #[label(resolve_macro_cannot_use_as_derive)]
+    Derive {
+        #[primary_span]
+        span: Span,
+        ident: Ident,
+    },
+}
+
+#[derive(Subdiagnostic)]
 #[note(resolve_missing_macro_rules_name)]
 pub(crate) struct MaybeMissingMacroRulesName {
     #[primary_span]