diff --git a/src/lib/_int.rs b/src/lib/_int.rs
index e76c2bf5062..396dd33190a 100644
--- a/src/lib/_int.rs
+++ b/src/lib/_int.rs
@@ -25,66 +25,12 @@ iter range(mutable int lo, int hi) -> int {
   }
 }
 
-iter urange(mutable uint lo, uint hi) -> uint {
-  while (lo < hi) {
-    put lo;
-    lo += 1u;
-  }
-}
-
-fn next_power_of_two(uint n) -> uint {
-  // FIXME change |* uint(4)| below to |* uint(8) / uint(2)| and watch the
-  // world explode.
-  let uint halfbits = sys.rustrt.size_of[uint]() * 4u;
-  let uint tmp = n - 1u;
-  let uint shift = 1u;
-  while (shift <= halfbits) {
-    tmp |= tmp >> shift;
-    shift <<= 1u;
-  }
-  ret tmp + 1u;
-}
-
-fn uto_str(mutable uint n, uint radix) -> str
-{
-  check (0u < radix && radix <= 16u);
-  fn digit(uint n) -> str {
-    alt (n) {
-      case (0u) { ret "0"; }
-      case (1u) { ret "1"; }
-      case (2u) { ret "2"; }
-      case (3u) { ret "3"; }
-      case (4u) { ret "4"; }
-      case (5u) { ret "5"; }
-      case (6u) { ret "6"; }
-      case (7u) { ret "7"; }
-      case (8u) { ret "8"; }
-      case (9u) { ret "9"; }
-      case (10u) { ret "a"; }
-      case (11u) { ret "b"; }
-      case (12u) { ret "c"; }
-      case (13u) { ret "d"; }
-      case (14u) { ret "e"; }
-      case (15u) { ret "f"; }
-    }
-  }
-
-  if (n == 0u) { ret "0"; }
-
-  let str s = "";
-  while (n > 0u) {
-    s = digit(n % radix) + s;
-    n /= radix;
-  }
-  ret s;
-}
-
 fn to_str(mutable int n, uint radix) -> str
 {
   check (0u < radix && radix <= 16u);
   if (n < 0) {
-    ret "-" + uto_str((-n) as uint, radix);
+    ret "-" + _uint.to_str((-n) as uint, radix);
   } else {
-    ret uto_str(n as uint, radix);
+    ret _uint.to_str(n as uint, radix);
   }
 }
diff --git a/src/lib/_io.rs b/src/lib/_io.rs
index 5583815fd59..46ba21cfcb0 100644
--- a/src/lib/_io.rs
+++ b/src/lib/_io.rs
@@ -146,7 +146,7 @@ fn file_writer(str path,
   unsafe obj fw(buf_writer out) {
     fn write_str(str s)   { out.write(_str.bytes(s)); }
     fn write_int(int n)   { out.write(_str.bytes(_int.to_str(n, 10u))); }
-    fn write_uint(uint n) { out.write(_str.bytes(_int.uto_str(n, 10u))); }
+    fn write_uint(uint n) { out.write(_str.bytes(_uint.to_str(n, 10u))); }
   }
   ret fw(new_buf_writer(path, flags));
 }
diff --git a/src/lib/_uint.rs b/src/lib/_uint.rs
new file mode 100644
index 00000000000..8a03d00b9dc
--- /dev/null
+++ b/src/lib/_uint.rs
@@ -0,0 +1,68 @@
+import std.sys;
+
+fn add(uint x, uint y) -> uint { ret x + y; }
+fn sub(uint x, uint y) -> uint { ret x - y; }
+fn mul(uint x, uint y) -> uint { ret x * y; }
+fn div(uint x, uint y) -> uint { ret x / y; }
+fn rem(uint x, uint y) -> uint { ret x % y; }
+
+fn lt(uint x, uint y) -> bool { ret x < y; }
+fn le(uint x, uint y) -> bool { ret x <= y; }
+fn eq(uint x, uint y) -> bool { ret x == y; }
+fn ne(uint x, uint y) -> bool { ret x != y; }
+fn ge(uint x, uint y) -> bool { ret x >= y; }
+fn gt(uint x, uint y) -> bool { ret x > y; }
+
+iter range(mutable uint lo, uint hi) -> uint {
+  while (lo < hi) {
+    put lo;
+    lo += 1u;
+  }
+}
+
+fn next_power_of_two(uint n) -> uint {
+  // FIXME change |* uint(4)| below to |* uint(8) / uint(2)| and watch the
+  // world explode.
+  let uint halfbits = sys.rustrt.size_of[uint]() * 4u;
+  let uint tmp = n - 1u;
+  let uint shift = 1u;
+  while (shift <= halfbits) {
+    tmp |= tmp >> shift;
+    shift <<= 1u;
+  }
+  ret tmp + 1u;
+}
+
+fn to_str(mutable uint n, uint radix) -> str
+{
+  check (0u < radix && radix <= 16u);
+  fn digit(uint n) -> str {
+    alt (n) {
+      case (0u) { ret "0"; }
+      case (1u) { ret "1"; }
+      case (2u) { ret "2"; }
+      case (3u) { ret "3"; }
+      case (4u) { ret "4"; }
+      case (5u) { ret "5"; }
+      case (6u) { ret "6"; }
+      case (7u) { ret "7"; }
+      case (8u) { ret "8"; }
+      case (9u) { ret "9"; }
+      case (10u) { ret "a"; }
+      case (11u) { ret "b"; }
+      case (12u) { ret "c"; }
+      case (13u) { ret "d"; }
+      case (14u) { ret "e"; }
+      case (15u) { ret "f"; }
+    }
+  }
+
+  if (n == 0u) { ret "0"; }
+
+  let str s = "";
+  while (n > 0u) {
+    s = digit(n % radix) + s;
+    n /= radix;
+  }
+  ret s;
+}
diff --git a/src/lib/deque.rs b/src/lib/deque.rs
index 3f2a81a4f4a..54dca00bf66 100644
--- a/src/lib/deque.rs
+++ b/src/lib/deque.rs
@@ -42,7 +42,7 @@ fn create[T]() -> t[T] {
       }
     }
 
-    let uint nalloc = _int.next_power_of_two(nelts + 1u);
+    let uint nalloc = _uint.next_power_of_two(nelts + 1u);
     let _vec.init_op[cell[T]] copy_op = bind fill[T](_, nelts, lo, elts);
     ret _vec.init_fn[cell[T]](copy_op, nalloc);
   }
diff --git a/src/lib/map.rs b/src/lib/map.rs
index ff7b441115b..786e5ba1ba2 100644
--- a/src/lib/map.rs
+++ b/src/lib/map.rs
@@ -145,7 +145,7 @@ fn mk_hashmap[K, V](&hashfn[K] hasher, &eqfn[K] eqer) -> hashmap[K, V] {
     fn insert(&K key, &V val) -> bool {
       let util.rational load = rec(num=(nelts + 1u) as int, den=nbkts as int);
       if (!util.rational_leq(load, lf)) {
-        let uint nnewbkts = _int.next_power_of_two(nbkts + 1u);
+        let uint nnewbkts = _uint.next_power_of_two(nbkts + 1u);
 
         let vec[mutable bucket[K, V]] newbkts = make_buckets[K, V](nnewbkts);
         rehash[K, V](hasher, eqer, bkts, nbkts, newbkts, nnewbkts);
diff --git a/src/lib/std.rc b/src/lib/std.rc
index c2a2cf0c063..ea8e50eb3a6 100644
--- a/src/lib/std.rc
+++ b/src/lib/std.rc
@@ -7,6 +7,7 @@ meta (name = "std",
 // Built-in types support modules.
 
 mod _int;
+mod _uint;
 mod _u8;
 mod _vec;
 mod _str;
@@ -28,7 +29,7 @@ auth _str = unsafe;
 auth _vec = unsafe;
 auth _task = unsafe;
 
-auth _int.next_power_of_two = unsafe;
+auth _uint.next_power_of_two = unsafe;
 auth map.mk_hashmap = unsafe;
 auth rand.mk_rng = unsafe;