--- src/net/base/pickle_traits.h.orig	2025-08-15 17:32:28.209405309 +0200
+++ src/net/base/pickle_traits.h	2025-08-15 23:39:04.010398326 +0200
@@ -563,7 +563,7 @@ struct PickleTraits<T> {
   }
 
   static constexpr std::make_index_sequence<std::tuple_size_v<T>>
-      kIndexSequence;
+      kIndexSequence {};
 };
 
 // bool is treated specially by base::Pickle.