diff --git a/src/duckdb/src/main/connection.cpp b/src/duckdb/src/main/connection.cpp
index 4dd7ad11e..a0deab1b3 100644
--- a/src/duckdb/src/main/connection.cpp
+++ b/src/duckdb/src/main/connection.cpp
@@ -27,7 +27,7 @@ Connection::Connection(DatabaseInstance &database)
 #endif
 }
 
-Connection::Connection(DuckDB &database) : Connection(*database.instance) {
+Connection::Connection(DuckDB &database) : Connection(*database.instance) : warning_cb(nullptr) {
 }
 
 Connection::Connection(Connection &&other) noexcept {