diff --git a/src/libcollections/slice.rs b/src/libcollections/slice.rs
index 07db33c6be85b..588ad7a319ac3 100644
--- a/src/libcollections/slice.rs
+++ b/src/libcollections/slice.rs
@@ -770,7 +770,7 @@ impl<T> [T] {
     /// let r = s.binary_search_by_key(&1, |&(a,b)| b);
     /// assert!(match r { Ok(1...4) => true, _ => false, });
     /// ```
-    #[unstable(feature = "slice_binary_search_by_key", reason = "recently added", issue = "0")]
+    #[unstable(feature = "slice_binary_search_by_key", reason = "recently added", issue = "33018")]
     #[inline]
     pub fn binary_search_by_key<B, F>(&self, b: &B, f: F) -> Result<usize, usize>
         where F: FnMut(&T) -> B,
diff --git a/src/libcore/slice.rs b/src/libcore/slice.rs
index 68f5a725b74bc..eb12ee281776b 100644
--- a/src/libcore/slice.rs
+++ b/src/libcore/slice.rs
@@ -158,7 +158,7 @@ pub trait SliceExt {
     #[stable(feature = "copy_from_slice", since = "1.9.0")]
     fn copy_from_slice(&mut self, src: &[Self::Item]) where Self::Item: Copy;
 
-    #[unstable(feature = "slice_binary_search_by_key", reason = "recently added", issue = "0")]
+    #[unstable(feature = "slice_binary_search_by_key", reason = "recently added", issue = "33018")]
     fn binary_search_by_key<B, F>(&self, b: &B, f: F) -> Result<usize, usize>
         where F: FnMut(&Self::Item) -> B,
               B: Ord;