diff --git a/src/test/interfaces_added.cpp b/src/test/interfaces_added.cpp
index 7117611..c60298e 100644
--- a/src/test/interfaces_added.cpp
+++ b/src/test/interfaces_added.cpp
@@ -15,8 +15,8 @@
 
 // This is the data structure that comes in via the InterfacesAdded
 // signal
-InterfacesAdded createInterfacesAdded(const std::string& interface,
-                                      const std::string& property)
+static InterfacesAdded createInterfacesAdded(const std::string& interface,
+                                             const std::string& property)
 {
     std::vector<Association> associations = {
         {"inventory", "error",