diff --git a/src/hb-map.hh b/src/hb-map.hh
index 790457f..311e612 100644
--- a/src/hb-map.hh
+++ b/src/hb-map.hh
@@ -44,7 +44,7 @@
 
   hb_hashmap_t (const hb_hashmap_t& o) : hb_hashmap_t () { hb_copy (o, *this); }
   hb_hashmap_t (hb_hashmap_t&& o) : hb_hashmap_t () { hb_swap (*this, o); }
-  hb_hashmap_t& operator= (const hb_hashmap_t&& o)  { hb_copy (o, *this); return *this; }
+  hb_hashmap_t& operator= (const hb_hashmap_t& o)  { hb_copy (o, *this); return *this; }
   hb_hashmap_t& operator= (hb_hashmap_t&& o)  { hb_swap (*this, o); return *this; }
 
   hb_hashmap_t (std::initializer_list<hb_pair_t<K, V>> lst) : hb_hashmap_t ()