diff --git a/src/comp/metadata/tydecode.rs b/src/comp/metadata/tydecode.rs
index e23c2aa2193..961d7f1f400 100644
--- a/src/comp/metadata/tydecode.rs
+++ b/src/comp/metadata/tydecode.rs
@@ -411,11 +411,10 @@ fn parse_def_id(buf: &[u8]) -> ast::def_id {
     let crate_part = ivec::slice[u8](buf, 0u, colon_idx);
     let def_part = ivec::slice[u8](buf, colon_idx + 1u, len);
 
-    // FIXME: Remove these ivec->vec conversions.
-    let crate_part_vec = [];
-    let def_part_vec = [];
-    for b: u8  in crate_part { crate_part_vec += [b]; }
-    for b: u8  in def_part { def_part_vec += [b]; }
+    let crate_part_vec = ~[];
+    let def_part_vec = ~[];
+    for b: u8  in crate_part { crate_part_vec += ~[b]; }
+    for b: u8  in def_part { def_part_vec += ~[b]; }
 
     let crate_num = uint::parse_buf(crate_part_vec, 10u) as int;
     let def_num = uint::parse_buf(def_part_vec, 10u) as int;
diff --git a/src/lib/uint.rs b/src/lib/uint.rs
index 248ac494d43..84eceb3b6d6 100644
--- a/src/lib/uint.rs
+++ b/src/lib/uint.rs
@@ -42,9 +42,9 @@ fn next_power_of_two(n: uint) -> uint {
     ret tmp + 1u;
 }
 
-fn parse_buf(buf: vec[u8], radix: uint) -> uint {
-    if vec::len[u8](buf) == 0u { log_err "parse_buf(): buf is empty"; fail; }
-    let i = vec::len[u8](buf) - 1u;
+fn parse_buf(buf: &[u8], radix: uint) -> uint {
+    if ivec::len[u8](buf) == 0u { log_err "parse_buf(): buf is empty"; fail; }
+    let i = ivec::len[u8](buf) - 1u;
     let power = 1u;
     let n = 0u;
     while true {
diff --git a/src/test/bench/shootout-pfib.rs b/src/test/bench/shootout-pfib.rs
index 4e868b801d2..101883d2ba0 100644
--- a/src/test/bench/shootout-pfib.rs
+++ b/src/test/bench/shootout-pfib.rs
@@ -89,8 +89,7 @@ fn main(argv: vec[str]) {
         if opts.stress {
             stress(2);
         } else {
-            let max = uint::parse_buf(ivec::to_vec(str::bytes(iargv.(1))),
-                                      10u) as int;
+            let max = uint::parse_buf(str::bytes(iargv.(1)), 10u) as int;
 
             let num_trials = 10;
 
diff --git a/src/test/bench/task-perf-spawnalot.rs b/src/test/bench/task-perf-spawnalot.rs
index 447de996b8b..378d0a53e97 100644
--- a/src/test/bench/task-perf-spawnalot.rs
+++ b/src/test/bench/task-perf-spawnalot.rs
@@ -20,7 +20,7 @@ fn main(args: vec[str]) {
     let n = if ivec::len(iargs) < 2u {
         10u
     } else {
-        uint::parse_buf(ivec::to_vec(str::bytes(iargs.(1))), 10u)
+        uint::parse_buf(str::bytes(iargs.(1)), 10u)
     };
     let i = 0u;
     while i < n {