diff --git a/lib/config/applyrule.cpp b/lib/config/applyrule.cpp
index 5042eb6b6..e05bce7b4 100644
--- a/lib/config/applyrule.cpp
+++ b/lib/config/applyrule.cpp
@@ -111,12 +111,14 @@ bool ApplyRule::IsValidTargetType(const String& sourceType, const String& target
 	return false;
 }
 
-std::vector<String> ApplyRule::GetTargetTypes(const String& sourceType)
+const std::vector<String>& ApplyRule::GetTargetTypes(const String& sourceType)
 {
 	auto it = m_Types.find(sourceType);
 
-	if (it == m_Types.end())
-		return std::vector<String>();
+	if (it == m_Types.end()) {
+		static const std::vector<String> noTypes;
+		return noTypes;
+	}
 
 	return it->second;
 }
diff --git a/lib/config/applyrule.hpp b/lib/config/applyrule.hpp
index 303b259e1..1d6e65a13 100644
--- a/lib/config/applyrule.hpp
+++ b/lib/config/applyrule.hpp
@@ -43,7 +43,7 @@ public:
 	static void RegisterType(const String& sourceType, const std::vector<String>& targetTypes);
 	static bool IsValidSourceType(const String& sourceType);
 	static bool IsValidTargetType(const String& sourceType, const String& targetType);
-	static std::vector<String> GetTargetTypes(const String& sourceType);
+	static const std::vector<String>& GetTargetTypes(const String& sourceType);
 
 	static void CheckMatches(bool silent);
 
diff --git a/lib/config/config_parser.yy b/lib/config/config_parser.yy
index 8fa10e71f..939681e68 100644
--- a/lib/config/config_parser.yy
+++ b/lib/config/config_parser.yy
@@ -1165,7 +1165,7 @@ apply:
 
 		if (!ApplyRule::IsValidTargetType(type, target)) {
 			if (target == "") {
-				std::vector<String> types = ApplyRule::GetTargetTypes(type);
+				auto& types (ApplyRule::GetTargetTypes(type));
 				String typeNames;
 
 				for (std::vector<String>::size_type i = 0; i < types.size(); i++) {