diff --git a/src/gui.h b/src/gui.h
index 0a1d274..1882000 100644
--- a/src/gui.h
+++ b/src/gui.h
@@ -176,7 +176,7 @@
 				// to reduce the count.
 #endif
 
-#if FEAT_GUI_HAIKU
+#ifdef FEAT_GUI_HAIKU
     VimScrollBar *id;		// Pointer to real scroll bar
 #endif
 #ifdef FEAT_GUI_PHOTON