diff --git a/src/endgame.h b/src/endgame.h
index 453d8b29..392788cf 100644
--- a/src/endgame.h
+++ b/src/endgame.h
@@ -90,7 +90,7 @@ struct Endgame : public EndgameBase<T> {
   T operator()(const Position&) const;
 
 private:
-  const Color strongSide, weakSide;
+  Color strongSide, weakSide;
 };