expand: Move some more derive logic to `rustc_builtin_macros`

2 files changed, 9 insertions, 8 deletions

diff --git a/compiler/rustc_builtin_macros/src/cfg_eval.rs b/compiler/rustc_builtin_macros/src/cfg_eval.rs
index 79dc857074d..415822c4573 100644
--- a/compiler/rustc_builtin_macros/src/cfg_eval.rs
+++ b/compiler/rustc_builtin_macros/src/cfg_eval.rs
@@ -24,19 +24,18 @@ crate fn expand(
     annotatable: Annotatable,
 ) -> Vec<Annotatable> {
     check_builtin_macro_attribute(ecx, meta_item, sym::cfg_eval);
-    cfg_eval(ecx, annotatable)
+    vec![cfg_eval(ecx, annotatable)]
 }
 
-crate fn cfg_eval(ecx: &ExtCtxt<'_>, annotatable: Annotatable) -> Vec<Annotatable> {
-    let mut visitor = CfgEval {
+crate fn cfg_eval(ecx: &ExtCtxt<'_>, annotatable: Annotatable) -> Annotatable {
+    CfgEval {
         cfg: &mut StripUnconfigured {
             sess: ecx.sess,
             features: ecx.ecfg.features,
             config_tokens: true,
         },
-    };
-    let annotatable = visitor.configure_annotatable(annotatable);
-    vec![annotatable]
+    }
+    .configure_annotatable(annotatable)
 }
 
 struct CfgEval<'a, 'b> {
diff --git a/compiler/rustc_builtin_macros/src/derive.rs b/compiler/rustc_builtin_macros/src/derive.rs
index 1bb050a40ce..60d6bae38b5 100644
--- a/compiler/rustc_builtin_macros/src/derive.rs
+++ b/compiler/rustc_builtin_macros/src/derive.rs
@@ -26,6 +26,8 @@ impl MultiItemModifier for Expander {
             return ExpandResult::Ready(vec![item]);
         }
 
+        let item = cfg_eval(ecx, item);
+
         let result =
             ecx.resolver.resolve_derives(ecx.current_expansion.id, ecx.force_mode, &|| {
                 let template =
@@ -54,12 +56,12 @@ impl MultiItemModifier for Expander {
                         report_path_args(sess, &meta);
                         meta.path
                     })
-                    .map(|path| (path, None))
+                    .map(|path| (path, item.clone(), None))
                     .collect()
             });
 
         match result {
-            Ok(()) => ExpandResult::Ready(cfg_eval(ecx, item)),
+            Ok(()) => ExpandResult::Ready(vec![item]),
             Err(Indeterminate) => ExpandResult::Retry(item),
         }
     }