Make it opt-in

crates/hir_def/src/db.rs

@@ -51,6 +51,9 @@ pub trait InternDatabase: SourceDatabase {
 
 #[salsa::query_group(DefDatabaseStorage)]
 pub trait DefDatabase: InternDatabase + AstDatabase + Upcast<dyn AstDatabase> {
+    #[salsa::input]
+    fn enable_proc_attr_macros(&self) -> bool;
+
     #[salsa::invoke(ItemTree::file_item_tree_query)]
     fn file_item_tree(&self, file_id: HirFileId) -> Arc<ItemTree>;
 

crates/hir_def/src/nameres/collector.rs

@@ -1067,6 +1067,10 @@ impl DefCollector<'_> {
                         }
                     }
 
+                    if !self.db.enable_proc_attr_macros() {
+                        return true;
+                    }
+
                     // Not resolved to a derive helper, so try to resolve as a macro.
                     match attr_macro_as_call_id(
                         ast_id,

crates/hir_def/src/test_db.rs

@@ -30,12 +30,19 @@ use crate::{
     crate::db::InternDatabaseStorage,
     crate::db::DefDatabaseStorage
 )]
-#[derive(Default)]
 pub(crate) struct TestDB {
     storage: salsa::Storage<TestDB>,
     events: Mutex<Option<Vec<salsa::Event>>>,
 }
 
+impl Default for TestDB {
+    fn default() -> Self {
+        let mut this = Self { storage: Default::default(), events: Default::default() };
+        this.set_enable_proc_attr_macros(true);
+        this
+    }
+}
+
 impl Upcast<dyn AstDatabase> for TestDB {
     fn upcast(&self) -> &(dyn AstDatabase + 'static) {
         &*self