diff --git a/src/generic/splitter.cpp b/src/generic/splitter.cpp
index 03422af402..bbdaad1e6a 100644
--- a/src/generic/splitter.cpp
+++ b/src/generic/splitter.cpp
@@ -200,7 +200,7 @@ void wxSplitterWindow::OnMouseEvent(wxMouseEvent& event)
     // following the mouse movement while it drags the sash, without it we only
     // draw the sash at the new position but only resize the windows when the
     // dragging is finished
-#ifdef __WXMAC__ && TARGET_API_MAC_OSX == 1
+#if defined( __WXMAC__ ) && TARGET_API_MAC_OSX == 1
     bool isLive = true ;
 #else
     bool isLive = (GetWindowStyleFlag() & wxSP_LIVE_UPDATE) != 0;