diff --git a/src/test/bench/core-map.rs b/src/test/bench/core-map.rs
index bbbd878e8b8..112d4fd0912 100644
--- a/src/test/bench/core-map.rs
+++ b/src/test/bench/core-map.rs
@@ -8,13 +8,15 @@
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.
 
+#![feature(unboxed_closures)]
+
 use std::collections::{TrieMap, TreeMap, HashMap, HashSet};
 use std::os;
 use std::rand::{Rng, IsaacRng, SeedableRng};
 use std::time::Duration;
 use std::uint;
 
-fn timed(label: &str, f: ||) {
+fn timed<F>(label: &str, f: F) where F: FnMut() {
     println!("  {}: {}", label, Duration::span(f));
 }
 
diff --git a/src/test/bench/core-set.rs b/src/test/bench/core-set.rs
index 07300b73c85..38c31da1a6d 100644
--- a/src/test/bench/core-set.rs
+++ b/src/test/bench/core-set.rs
@@ -10,6 +10,8 @@
 
 // ignore-pretty very bad with line comments
 
+#![feature(unboxed_closures)]
+
 extern crate collections;
 extern crate rand;
 
@@ -31,7 +33,7 @@ struct Results {
     delete_strings: Duration,
 }
 
-fn timed(result: &mut Duration, op: ||) {
+fn timed<F>(result: &mut Duration, op: F) where F: FnOnce() {
     *result = Duration::span(op);
 }
 
@@ -66,7 +68,7 @@ impl Results {
                      rand_cap: uint,
                      f: || -> T) { {
             let mut set = f();
-            timed(&mut self.sequential_ints, || {
+            timed(&mut self.sequential_ints, move || {
                 for i in range(0u, num_keys) {
                     set.insert(i);
                 }
@@ -79,7 +81,7 @@ impl Results {
 
         {
             let mut set = f();
-            timed(&mut self.random_ints, || {
+            timed(&mut self.random_ints, move || {
                 for _ in range(0, num_keys) {
                     set.insert(rng.gen::<uint>() % rand_cap);
                 }
@@ -92,7 +94,7 @@ impl Results {
                 set.insert(i);
             }
 
-            timed(&mut self.delete_ints, || {
+            timed(&mut self.delete_ints, move || {
                 for i in range(0u, num_keys) {
                     assert!(set.remove(&i));
                 }
@@ -108,7 +110,7 @@ impl Results {
                      f: || -> T) {
         {
             let mut set = f();
-            timed(&mut self.sequential_strings, || {
+            timed(&mut self.sequential_strings, move || {
                 for i in range(0u, num_keys) {
                     set.insert(i.to_string());
                 }
@@ -121,7 +123,7 @@ impl Results {
 
         {
             let mut set = f();
-            timed(&mut self.random_strings, || {
+            timed(&mut self.random_strings, move || {
                 for _ in range(0, num_keys) {
                     let s = rng.gen::<uint>().to_string();
                     set.insert(s);
@@ -134,7 +136,7 @@ impl Results {
             for i in range(0u, num_keys) {
                 set.insert(i.to_string());
             }
-            timed(&mut self.delete_strings, || {
+            timed(&mut self.delete_strings, move || {
                 for i in range(0u, num_keys) {
                     assert!(set.remove(&i.to_string()));
                 }
diff --git a/src/test/bench/core-std.rs b/src/test/bench/core-std.rs
index 24bd26b0288..6e2cd508291 100644
--- a/src/test/bench/core-std.rs
+++ b/src/test/bench/core-std.rs
@@ -12,6 +12,7 @@
 // Microbenchmarks for various functions in std and extra
 
 #![feature(macro_rules)]
+#![feature(unboxed_closures)]
 
 use std::io::File;
 use std::mem::swap;
@@ -41,7 +42,7 @@ fn main() {
     bench!(is_utf8_multibyte);
 }
 
-fn maybe_run_test(argv: &[String], name: String, test: ||) {
+fn maybe_run_test<F>(argv: &[String], name: String, test: F) where F: FnOnce() {
     let mut run_test = false;
 
     if os::getenv("RUST_BENCH").is_some() {