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src/hb-open-type.hh

diff --git a/src/hb-open-type.hh b/src/hb-open-type.hh
index 2990b0d..2bfbee5 100644
--- a/src/hb-open-type.hh
+++ b/src/hb-open-type.hh
@@ -305,6 +305,7 @@
     return ret;
   }
 
+  /* TODO: Somehow merge this with previous function into a serialize_dispatch(). */
   template <typename ...Ts>
   bool serialize_copy (hb_serialize_context_t *c, const Type &src, const void *base, Ts &&...ds)
   {