diff --git a/lib/exprengine.cpp b/lib/exprengine.cpp
index d062e6881..5bd6938ca 100644
--- a/lib/exprengine.cpp
+++ b/lib/exprengine.cpp
@@ -498,8 +498,7 @@ namespace {
                          CWE cwe,
                          bool inconclusive,
                          bool incomplete,
-                         const std::string functionName) OVERRIDE
-
+                         const std::string &functionName) OVERRIDE
         {
             if (errorPath.empty())
                 mTrackExecution->addError(tok->linenr());
diff --git a/lib/exprengine.h b/lib/exprengine.h
index a5df12c01..6bea4eea8 100644
--- a/lib/exprengine.h
+++ b/lib/exprengine.h
@@ -86,7 +86,7 @@ namespace ExprEngine {
                                  CWE cwe,
                                  bool inconclusive,
                                  bool incomplete=false,
-                                 const std::string functionName = std::string()) = 0;
+                                 const std::string &functionName = std::string()) = 0;
         ErrorPath errorPath;
     };