diff --git a/src/libutil/error.hh b/src/libutil/error.hh
index 1e6102ce1..6982e30aa 100644
--- a/src/libutil/error.hh
+++ b/src/libutil/error.hh
@@ -67,7 +67,11 @@ struct ErrPos {
     {
         line = pos.line;
         column = pos.column;
-        file = pos.file;
+        // is file symbol null?
+        if (pos.file.set())
+            file = pos.file;
+        else
+            file = "";
         return *this;
     }