diff --git a/contrib/Chaco/main/interface.c b/contrib/Chaco/main/interface.c
index 26b4fc2cd1c85888c10495129bba9107b1025690..b883078cb5aec4c7e31ed6849eb205369c6071bb 100644
--- a/contrib/Chaco/main/interface.c
+++ b/contrib/Chaco/main/interface.c
@@ -107,6 +107,8 @@ int       terminal_propogation;
 /* 	} */
 /* 	read_params(params_file); */
 /*     } */
+/* Gmsh - required if above commented out */
+    params_file = NULL;
 /* Gmsh - end */
 /* Gmsh - override some parameters */
     FREE_GRAPH = 0;