diff --git a/src/libcore/cleanup.rs b/src/libcore/cleanup.rs
index 46dad7496da..ed1564cc426 100644
--- a/src/libcore/cleanup.rs
+++ b/src/libcore/cleanup.rs
@@ -5,6 +5,8 @@ use rt::rt_free;
 use sys::TypeDesc;
 use unsafe::transmute;
 
+export annihilate;
+
 /**
  * Runtime structures
  *
@@ -65,8 +67,7 @@ struct Task {
  * This runs at task death to free all boxes.
  */
 
-/// Destroys all managed memory (i.e. @ boxes) held by the current task.
-pub unsafe fn annihilate() {
+unsafe fn do_annihilate() {
     let task: *Task = transmute(rustrt::rust_get_task());
 
     // Pass 1: Make all boxes immortal.
@@ -104,6 +105,18 @@ pub unsafe fn annihilate() {
     }
 }
 
+/// Destroys all managed memory (i.e. @ boxes) held by the current task.
+#[cfg(notest)]
+#[lang="annihilate"]
+pub unsafe fn annihilate() {
+    do_annihilate();
+}
+
+#[cfg(test)]
+pub unsafe fn annihilate() {
+    do_annihilate();
+}
+
 /// Bindings to the runtime
 extern mod rustrt {
     #[rust_stack]
@@ -116,7 +129,7 @@ extern mod rustrt {
 
 #[cfg(test)]
 mod tests {
-    /*struct Knot {
+    struct Knot {
         mut a: Option<@Knot>
     }
 
@@ -147,6 +160,6 @@ mod tests {
             unsafe::forget(f_ref);
             unsafe::forget(f);
         }
-    }*/
+    }
 }
 
diff --git a/src/libcore/core.rc b/src/libcore/core.rc
index 8b5a218bb93..1e558a8ded4 100644
--- a/src/libcore/core.rc
+++ b/src/libcore/core.rc
@@ -62,6 +62,7 @@ export flate;
 export unit;
 export uniq;
 export repr;
+export cleanup;
 
 // NDM seems to be necessary for resolve to work
 export option_iter;
@@ -228,6 +229,7 @@ mod unsafe;
 mod mutable;
 mod flate;
 mod repr;
+mod cleanup;
 
 // Modules supporting compiler-generated code
 // Exported but not part of the public interface
@@ -244,7 +246,6 @@ mod unicode;
 mod private;
 mod cmath;
 mod stackwalk;
-mod cleanup;
 
 // Local Variables:
 // mode: rust;
diff --git a/src/rustc/middle/lang_items.rs b/src/rustc/middle/lang_items.rs
index 5f9c17cebd5..cd30e575bda 100644
--- a/src/rustc/middle/lang_items.rs
+++ b/src/rustc/middle/lang_items.rs
@@ -45,7 +45,8 @@ struct LanguageItems {
     mut ord_trait: Option<def_id>,
 
     mut str_eq_fn: Option<def_id>,
-    mut uniq_str_eq_fn: Option<def_id>
+    mut uniq_str_eq_fn: Option<def_id>,
+    mut annihilate_fn: Option<def_id>
 }
 
 mod LanguageItems {
@@ -73,7 +74,8 @@ mod LanguageItems {
             ord_trait: None,
 
             str_eq_fn: None,
-            uniq_str_eq_fn: None
+            uniq_str_eq_fn: None,
+            annihilate_fn: None
         }
     }
 }
@@ -107,6 +109,7 @@ fn LanguageItemCollector(crate: @crate, session: session,
 
     item_refs.insert(~"str_eq", &mut items.str_eq_fn);
     item_refs.insert(~"uniq_str_eq", &mut items.uniq_str_eq_fn);
+    item_refs.insert(~"annihilate", &mut items.annihilate_fn);
 
     LanguageItemCollector {
         crate: crate,