diff --git a/src/test/bench/core-map.rs b/src/test/bench/core-map.rs
index 68ba40749f2dd..acaedb7571e05 100644
--- a/src/test/bench/core-map.rs
+++ b/src/test/bench/core-map.rs
@@ -302,10 +302,10 @@ fn main() {
         }
     };
 
-    let seed = ~[1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+    const seed: [u8 * 10] = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
 
     {
-        let rng = rand::seeded_rng(&seed);
+        let rng = rand::seeded_rng(seed);
         let mut results = empty_results();
         old_int_benchmarks(rng, num_keys, &mut results);
         old_str_benchmarks(rng, num_keys, &mut results);
@@ -313,7 +313,7 @@ fn main() {
     }
 
     {
-        let rng = rand::seeded_rng(&seed);
+        let rng = rand::seeded_rng(seed);
         let mut results = empty_results();
         linear_int_benchmarks(rng, num_keys, &mut results);
         linear_str_benchmarks(rng, num_keys, &mut results);
@@ -321,7 +321,7 @@ fn main() {
     }
 
     {
-        let rng = rand::seeded_rng(&seed);
+        let rng = rand::seeded_rng(seed);
         let mut results = empty_results();
         tree_int_benchmarks(rng, num_keys, &mut results);
         tree_str_benchmarks(rng, num_keys, &mut results);
diff --git a/src/test/bench/core-set.rs b/src/test/bench/core-set.rs
index cfb27329174fe..1c14646211124 100644
--- a/src/test/bench/core-set.rs
+++ b/src/test/bench/core-set.rs
@@ -152,11 +152,11 @@ fn main() {
         }
     };
 
-    let seed = ~[1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+    const seed: [u8 * 10] = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
     let max = 200000;
 
     {
-        let rng = rand::seeded_rng(&seed);
+        let rng = rand::seeded_rng(seed);
         let mut results = empty_results();
         results.bench_int(rng, num_keys, max, || LinearSet::new::<uint>());
         results.bench_str(rng, num_keys, || LinearSet::new::<~str>());
@@ -164,7 +164,7 @@ fn main() {
     }
 
     {
-        let rng = rand::seeded_rng(&seed);
+        let rng = rand::seeded_rng(seed);
         let mut results = empty_results();
         results.bench_int(rng, num_keys, max, || TreeSet::new::<uint>());
         results.bench_str(rng, num_keys, || TreeSet::new::<~str>());
@@ -172,7 +172,7 @@ fn main() {
     }
 
     {
-        let rng = rand::seeded_rng(&seed);
+        let rng = rand::seeded_rng(seed);
         let mut results = empty_results();
         results.bench_int(rng, num_keys, max, || BitvSet::new());
         write_results("std::bitv::BitvSet", &results);