diff --git a/WORKSPACE.bazel b/WORKSPACE.bazel
index e7c5173..f8865f5 100644
--- a/WORKSPACE.bazel
+++ b/WORKSPACE.bazel
@@ -48,7 +48,7 @@ load("@io_bazel_rules_go//go:deps.bzl", "go_register_toolchains", "go_rules_depe
 
 go_rules_dependencies()
 
-go_register_toolchains(version = "1.15.5")
+go_register_toolchains(version = "host")
 
 # Install gtest.
 http_archive(
diff --git a/dpf/tuple.h b/dpf/tuple.h
index a42113f..4596305 100644
--- a/dpf/tuple.h
+++ b/dpf/tuple.h
@@ -103,7 +103,7 @@ namespace dpf_internal {
 template <typename... T, std::size_t... I>
 constexpr Tuple<T...> add(const Tuple<T...>& lhs, const Tuple<T...>& rhs,
                           std::index_sequence<I...>) {
-  return Tuple<T...>{std::get<I>(lhs.value()) + std::get<I>(rhs.value())...};
+  return Tuple<T...>{T(std::get<I>(lhs.value()) + std::get<I>(rhs.value()))...};
 }
 
 template <typename... T, std::size_t... I>