diff --git a/src/mred/mred.cxx b/src/mred/mred.cxx
index 9f48987f91..4d931079e8 100644
--- a/src/mred/mred.cxx
+++ b/src/mred/mred.cxx
@@ -3152,9 +3152,11 @@ wxFrame *MrEdApp::OnInit(void)
 # endif
 #endif
 
-#ifdef OS_X
+#ifdef wx_mac
+# ifdef OS_X
   /* Hack to make sure it's referenced, so that xform doesn't throw it away. */
   wx_in_terminal = wx_in_terminal;
+# endif
 #endif
 
   mred_run_from_cmd_line(argc, argv, setup_basic_env);