diff --git a/src/CppParser/CppParser.h b/src/CppParser/CppParser.h
index 79b62f50..3f128894 100644
--- a/src/CppParser/CppParser.h
+++ b/src/CppParser/CppParser.h
@@ -51,7 +51,7 @@ namespace CppSharp { namespace CppParser {
         bool skipFunctionBodies = true;
 
     private:
-        std::string clangVersion;
+        const std::string& clangVersion const;
     };
 
     struct CS_API CppLinkerOptions
@@ -132,4 +132,4 @@ namespace CppSharp { namespace CppParser {
                                   bool Last);
     };
 
-}} // namespace CppSharp::CppParser
\ No newline at end of file
+}} // namespace CppSharp::CppParser