diff --git a/src/dense/ftdense.c b/src/dense/ftdense.c
index 78700a9b9..cb886ffa1 100644
--- a/src/dense/ftdense.c
+++ b/src/dense/ftdense.c
@@ -448,6 +448,7 @@ dense_render_glyph( dense_worker* worker, const FT_Bitmap* target )
     }
   }
 
+  free(worker->m_a);
   return error;
 }