---

yaml
---
r: 188128
b: refs/heads/try
c: f38b83b
h: refs/heads/master
v: v3

Author: Ms2ger

[refs]

@@ -2,7 +2,7 @@
 refs/heads/master: 38e97b99a6b133cb4c621c68e75b28abc6c617c1
 refs/heads/snap-stage1: e33de59e47c5076a89eadeb38f4934f58a3618a6
 refs/heads/snap-stage3: 3a96d6a9818fe2affc98a187fb1065120458cee9
-refs/heads/try: 2a37f7f07ca6bc3e3f19c6bb33b25bbc35f561a2
+refs/heads/try: f38b83b3609b060df5ab3d2a57e98020b8b29efb
 refs/tags/release-0.1: 1f5c5126e96c79d22cb7862f75304136e204f105
 refs/heads/dist-snap: ba4081a5a8573875fed17545846f6f6902c8ba8d
 refs/tags/release-0.2: c870d2dffb391e14efb05aa27898f1f6333a9596

branches/try/src/librustc_lint/builtin.rs

@@ -741,23 +741,24 @@ impl LintPass for UnusedResults {
         }
 
         let t = ty::expr_ty(cx.tcx, expr);
-        let mut warned = false;
-        match t.sty {
+        let warned = match t.sty {
             ty::ty_tup(ref tys) if tys.is_empty() => return,
             ty::ty_bool => return,
             ty::ty_struct(did, _) |
             ty::ty_enum(did, _) => {
                 if ast_util::is_local(did) {
                     if let ast_map::NodeItem(it) = cx.tcx.map.get(did.node) {
-                        warned |= check_must_use(cx, &it.attrs, s.span);
+                        check_must_use(cx, &it.attrs, s.span)
+                    } else {
+                        false
                     }
                 } else {
                     let attrs = csearch::get_item_attrs(&cx.sess().cstore, did);
-                    warned |= check_must_use(cx, &attrs[..], s.span);
+                    check_must_use(cx, &attrs[..], s.span)
                 }
             }
-            _ => {}
-        }
+            _ => false,
+        };
         if !warned {
             cx.span_lint(UNUSED_RESULTS, s.span, "unused result");
         }