diff --git a/src/librustc/middle/cfg/mod.rs b/src/librustc/middle/cfg/mod.rs
index 0e9bd42a23a1..04f86d0a9bad 100644
--- a/src/librustc/middle/cfg/mod.rs
+++ b/src/librustc/middle/cfg/mod.rs
@@ -51,9 +51,6 @@ impl CFG {
     }
 
     pub fn node_is_reachable(&self, id: ast::NodeId) -> bool {
-        for node in self.graph.depth_traverse(self.entry) {
-            if node.id == id { return true }
-        }
-        return false;
+        self.graph.depth_traverse(self.entry).any(|node| node.id == id)
     }
 }
diff --git a/src/librustc/middle/graph.rs b/src/librustc/middle/graph.rs
index 4397f03a6428..3ba72801e2bf 100644
--- a/src/librustc/middle/graph.rs
+++ b/src/librustc/middle/graph.rs
@@ -313,12 +313,10 @@ pub struct DepthFirstTraversal<'g, N:'g, E:'g> {
 
 impl<'g, N, E> Iterator<&'g N> for DepthFirstTraversal<'g, N, E> {
     fn next(&mut self) -> Option<&'g N> {
-        while self.stack.len() > 0 {
-            let idx = self.stack.pop().unwrap();
-            if self.visited.contains(&idx.node_id()) {
+        while let Some(idx) = self.stack.pop() {
+            if self.visited.insert(idx.node_id()) {
                 continue;
             }
-            self.visited.insert(idx.node_id());
             self.graph.each_outgoing_edge(idx, |_, e| -> bool {
                 if !self.visited.contains(&e.target().node_id()) {
                     self.stack.push(e.target());
diff --git a/src/librustc_trans/trans/base.rs b/src/librustc_trans/trans/base.rs
index 2cfcce2a961a..5b90dec8323b 100644
--- a/src/librustc_trans/trans/base.rs
+++ b/src/librustc_trans/trans/base.rs
@@ -1468,7 +1468,7 @@ pub fn new_fn_ctxt<'a, 'tcx>(ccx: &'a CrateContext<'a, 'tcx>,
     let debug_context = debuginfo::create_function_debug_context(ccx, id, param_substs, llfndecl);
     let (blk_id, cfg) = build_cfg(ccx.tcx(), id);
     let nested_returns = if let Some(ref cfg) = cfg {
-       has_nested_returns(ccx.tcx(), cfg, blk_id)
+        has_nested_returns(ccx.tcx(), cfg, blk_id)
     } else {
         false
     };