Add tracking issue for offset_to

Author: Amanieu

src/doc/unstable-book/src/offset-to.md

@@ -1,7 +1,7 @@
 # `offset_to`
 
-The tracking issue for this feature is: [#0]
+The tracking issue for this feature is: [#41079]
 
-[#0]: https://github.com/rust-lang/rust/issues/0
+[#41079]: https://github.com/rust-lang/rust/issues/41079
 
 ------------------------

src/libcore/ptr.rs

@@ -527,7 +527,7 @@ impl<T: ?Sized> *const T {
     ///     assert_eq!(unsafe { ptr2.offset(-2) }, ptr1);
     /// }
     /// ```
-    #[unstable(feature = "offset_to", issue = "0")]
+    #[unstable(feature = "offset_to", issue = "41079")]
     #[inline]
     pub fn offset_to(self, other: *const T) -> Option<isize> where T: Sized {
         let size = mem::size_of::<T>();
@@ -718,7 +718,7 @@ impl<T: ?Sized> *mut T {
     ///     assert_eq!(unsafe { ptr2.offset(-2) }, ptr1);
     /// }
     /// ```
-    #[unstable(feature = "offset_to", issue = "0")]
+    #[unstable(feature = "offset_to", issue = "41079")]
     #[inline]
     pub fn offset_to(self, other: *const T) -> Option<isize> where T: Sized {
         let size = mem::size_of::<T>();