1 files changed, 2 insertions, 1 deletions
diff --git a/searchcore/src/vespa/searchcore/proton/attribute/attribute_collection_spec_factory.h b/searchcore/src/vespa/searchcore/proton/attribute/attribute_collection_spec_factory.h
index 8ef06f20bac..06b3f677640 100644
--- a/searchcore/src/vespa/searchcore/proton/attribute/attribute_collection_spec_factory.h
+++ b/searchcore/src/vespa/searchcore/proton/attribute/attribute_collection_spec_factory.h
@@ -5,6 +5,7 @@
 #include "attribute_collection_spec.h"
 #include <vespa/searchcore/proton/common/alloc_strategy.h>
 #include <vespa/searchlib/common/serialnum.h>
+#include <optional>
 
 namespace vespa::config::search::internal { class InternalAttributesType; };
 
@@ -26,7 +27,7 @@ public:
     AttributeCollectionSpecFactory(const AllocStrategy& alloc_strategy, bool fastAccessOnly);
     ~AttributeCollectionSpecFactory();
 
-    std::unique_ptr<AttributeCollectionSpec> create(const AttributesConfig &attrCfg, uint32_t docIdLimit, search::SerialNum serialNum) const;
+    std::unique_ptr<AttributeCollectionSpec> create(const AttributesConfig &attrCfg, uint32_t docIdLimit, std::optional<search::SerialNum> serialNum) const;
 };
 
 } // namespace proton