diff --git a/utils/funcexp/functor.cpp b/utils/funcexp/functor.cpp
index 7fb55b47e..2696eaf1c 100644
--- a/utils/funcexp/functor.cpp
+++ b/utils/funcexp/functor.cpp
@@ -61,7 +61,7 @@ void Func::init()
     double* dp = reinterpret_cast<double*>(&dni);
     fDoubleNullVal = *dp;
 
-    fDoubleNullVal = joblist::LONGDOUBLENULL;
+    fLongDoubleNullVal = joblist::LONGDOUBLENULL;
 }