diff --git a/src/hb-font.cc b/src/hb-font.cc
index b73a87048..1c63b0344 100644
--- a/src/hb-font.cc
+++ b/src/hb-font.cc
@@ -2212,6 +2212,7 @@ hb_font_set_face (hb_font_t *font,
   hb_face_destroy (old);
 
   font->changed ();
+  font->serial_coords = font->serial;
 }
 
 /**