diff --git a/td/generate/tl_writer_jni_cpp.cpp b/td/generate/tl_writer_jni_cpp.cpp
index e0b628cc..b8c1c9e3 100644
--- a/td/generate/tl_writer_jni_cpp.cpp
+++ b/td/generate/tl_writer_jni_cpp.cpp
@@ -476,7 +476,7 @@ std::string TD_TL_writer_jni_cpp::gen_fetch_switch_case(const tl::tl_combinator
 
 std::string TD_TL_writer_jni_cpp::gen_fetch_switch_end() const {
   return "    default:\n"
-         "      UNREACHABLE();\n"
+         "      LOG(WARNING) << \"Unknown constructor found\";\n"
          "      return nullptr;\n"
          "  }\n";
 }