diff --git a/src/user/user_objects.cc b/src/user/user_objects.cc
index 88afaabe..875dc6b0 100644
--- a/src/user/user_objects.cc
+++ b/src/user/user_objects.cc
@@ -2144,6 +2144,7 @@ double mjCGeom::GetVolume() const {
     default:
       return 0;
   }
+  return 0;
 }