diff --git a/src/librustc/lib.rs b/src/librustc/lib.rs
index 0ff9626ae11a8..855f4a8197e35 100644
--- a/src/librustc/lib.rs
+++ b/src/librustc/lib.rs
@@ -109,7 +109,6 @@ pub mod util {
     pub mod common;
     pub mod ppaux;
     pub mod nodemap;
-    pub mod num;
     pub mod fs;
 }
 
diff --git a/src/librustc/util/num.rs b/src/librustc/util/num.rs
deleted file mode 100644
index da04976a96a37..0000000000000
--- a/src/librustc/util/num.rs
+++ /dev/null
@@ -1,98 +0,0 @@
-// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-pub trait ToPrimitive {
-    fn to_i8(&self) -> Option<i8>;
-    fn to_i16(&self) -> Option<i16>;
-    fn to_i32(&self) -> Option<i32>;
-    fn to_i64(&self) -> Option<i64>;
-    fn to_u8(&self) -> Option<u8>;
-    fn to_u16(&self) -> Option<u16>;
-    fn to_u32(&self) -> Option<u32>;
-    fn to_u64(&self) -> Option<u64>;
-}
-
-impl ToPrimitive for i64 {
-    fn to_i8(&self) -> Option<i8> {
-        if *self < i8::min_value() as i64 || *self > i8::max_value() as i64 {
-            None
-        } else {
-            Some(*self as i8)
-        }
-    }
-    fn to_i16(&self) -> Option<i16> {
-        if *self < i16::min_value() as i64 || *self > i16::max_value() as i64 {
-            None
-        } else {
-            Some(*self as i16)
-        }
-    }
-    fn to_i32(&self) -> Option<i32> {
-        if *self < i32::min_value() as i64 || *self > i32::max_value() as i64 {
-            None
-        } else {
-            Some(*self as i32)
-        }
-    }
-    fn to_i64(&self) -> Option<i64> {
-        Some(*self)
-    }
-    fn to_u8(&self) -> Option<u8> {
-        if *self < 0 || *self > u8::max_value() as i64 {
-            None
-        } else {
-            Some(*self as u8)
-        }
-    }
-    fn to_u16(&self) -> Option<u16> {
-        if *self < 0 || *self > u16::max_value() as i64 {
-            None
-        } else {
-            Some(*self as u16)
-        }
-    }
-    fn to_u32(&self) -> Option<u32> {
-        if *self < 0 || *self > u32::max_value() as i64 {
-            None
-        } else {
-            Some(*self as u32)
-        }
-    }
-    fn to_u64(&self) -> Option<u64> {
-        if *self < 0 {None} else {Some(*self as u64)}
-    }
-}
-
-impl ToPrimitive for u64 {
-    fn to_i8(&self) -> Option<i8> {
-        if *self > i8::max_value() as u64 {None} else {Some(*self as i8)}
-    }
-    fn to_i16(&self) -> Option<i16> {
-        if *self > i16::max_value() as u64 {None} else {Some(*self as i16)}
-    }
-    fn to_i32(&self) -> Option<i32> {
-        if *self > i32::max_value() as u64 {None} else {Some(*self as i32)}
-    }
-    fn to_i64(&self) -> Option<i64> {
-        if *self > i64::max_value() as u64 {None} else {Some(*self as i64)}
-    }
-    fn to_u8(&self) -> Option<u8> {
-        if *self > u8::max_value() as u64 {None} else {Some(*self as u8)}
-    }
-    fn to_u16(&self) -> Option<u16> {
-        if *self > u16::max_value() as u64 {None} else {Some(*self as u16)}
-    }
-    fn to_u32(&self) -> Option<u32> {
-        if *self > u32::max_value() as u64 {None} else {Some(*self as u32)}
-    }
-    fn to_u64(&self) -> Option<u64> {
-        Some(*self)
-    }
-}