diff --git a/src/libcore/core.rc b/src/libcore/core.rc
index 58f2281daf3..24ff59b7028 100644
--- a/src/libcore/core.rc
+++ b/src/libcore/core.rc
@@ -42,7 +42,7 @@ export libc, os, io, run, rand, sys, unsafe, logging;
 export arc, newcomm, comm, task, future;
 export extfmt;
 export tuple;
-export to_str;
+export to_str, to_bytes;
 export dvec, dvec_iter;
 export cmp;
 export num;