diff --git a/m-bitset.h b/m-bitset.h
index 9a7d7b3f..8d0f61a7 100644
--- a/m-bitset.h
+++ b/m-bitset.h
@@ -179,6 +179,7 @@ bitset_resize (bitset_t v, size_t size)
     v->alloc = newbytes;
   }
   v->size = size;
+  //FIXME: Last bit are not cleared.
   BITSETI_CONTRACT (v);
 }