diff --git a/tests/test_BuiltinFunctionRegister.hpp b/tests/test_BuiltinFunctionRegister.hpp
index cb8e4af6b72244736d4c0410e5c224c1d87fa7fb..7c361c9df4a6e4c3071ccef00c070313dba2bb5b 100644
--- a/tests/test_BuiltinFunctionRegister.hpp
+++ b/tests/test_BuiltinFunctionRegister.hpp
@@ -7,6 +7,8 @@
 #include <language/utils/TypeDescriptor.hpp>
 #include <utils/Exceptions.hpp>
 
+#include <unordered_map>
+
 template <>
 inline ASTNodeDataType ast_node_data_type_from<std::shared_ptr<const double>> =
   ASTNodeDataType::build<ASTNodeDataType::type_id_t>("builtin_t");