fix corner case in `loops` & `unused` (#4085)

fixes #4084

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/compress.js b/lib/compress.js
index bab390cf..2c21217e 100644
--- a/lib/compress.js
+++ b/lib/compress.js
@@ -4682,8 +4682,8 @@ merge(Compressor.prototype, {
                 }
                 var def = sym.definition();
                 if (!def) return;
-                if (def.scope !== self) return;
                 if (def.id in in_use_ids) return;
+                if (def.scope !== self && member(def, self.enclosed)) return;
                 log(sym, "Dropping unused loop variable {name}");
                 var value = node.object.drop_side_effect_free(compressor);
                 if (!value) return in_list ? List.skip : make_node(AST_EmptyStatement, node);