diff --git a/src/feature.h b/src/feature.h
index 5b915b8..762a70c 100644
--- a/src/feature.h
+++ b/src/feature.h
@@ -806,6 +806,13 @@
 #endif
 
 /*
+ * +vartabs		'vartabstop' and 'varsofttabstop' options.
+ */
+#ifdef FEAT_BIG
+# define FEAT_VARTABS
+#endif
+
+/*
  * Preferences:
  * ============
  */