diff --git a/googlemock/include/gmock/gmock-matchers.h b/googlemock/include/gmock/gmock-matchers.h
index 62829011..3c8cc32e 100644
--- a/googlemock/include/gmock/gmock-matchers.h
+++ b/googlemock/include/gmock/gmock-matchers.h
@@ -3235,6 +3235,11 @@ auto UnpackStructImpl(const T& t, MakeIndexSequence<16>, char) {
   const auto& [a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p] = t;
   return std::tie(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p);
 }
+template <typename T>
+auto UnpackStructImpl(const T& t, MakeIndexSequence<17>, char) {
+  const auto& [a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q] = t;
+  return std::tie(a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, p, q);
+}
 #endif  // defined(__cpp_structured_bindings)
 
 template <size_t I, typename T>