diff --git a/src/hb-ot-layout-gsub-table.hh b/src/hb-ot-layout-gsub-table.hh
index b64bdd0f5..e3f1b8d9a 100644
--- a/src/hb-ot-layout-gsub-table.hh
+++ b/src/hb-ot-layout-gsub-table.hh
@@ -677,7 +677,7 @@ struct Ligature
 
   void collect_glyphs (hb_collect_glyphs_context_t *c) const
   {
-    c->input->add_array (component.arrayZ, component.lenP1 ? component.lenP1 - 1 : 0);
+    c->input->add_array (component.arrayZ, component.get_length ());
     c->output->add (ligGlyph);
   }