diff --git a/src/libextra/ebml.rs b/src/libextra/ebml.rs
index 69eb9afad85..4634a7db05e 100644
--- a/src/libextra/ebml.rs
+++ b/src/libextra/ebml.rs
@@ -97,11 +97,14 @@ pub mod reader {
     use core::cast::transmute;
     use core::int;
     use core::io;
+    use core::option::{None, Option, Some};
 
     #[cfg(target_arch = "x86")]
     #[cfg(target_arch = "x86_64")]
-    use core::option::{None, Option, Some};
     use core::ptr::offset;
+
+    #[cfg(target_arch = "x86")]
+    #[cfg(target_arch = "x86_64")]
     use core::unstable::intrinsics::bswap32;
 
     // ebml reading