1 files changed, 1 insertions, 1 deletions
diff --git a/compiler/rustc_builtin_macros/src/cfg.rs b/compiler/rustc_builtin_macros/src/cfg.rs
index 48be680b619..1bc2512a7b0 100644
--- a/compiler/rustc_builtin_macros/src/cfg.rs
+++ b/compiler/rustc_builtin_macros/src/cfg.rs
@@ -28,7 +28,7 @@ pub fn expand_cfg(
             );
             MacEager::expr(cx.expr_bool(sp, matches_cfg))
         }
-        Err(mut err) => {
+        Err(err) => {
             err.emit();
             DummyResult::any(sp)
         }