diff --git a/Widgets/FrameBuffer.cpp b/Widgets/FrameBuffer.cpp
index 514d90abdf..7c2b4b53c4 100644
--- a/Widgets/FrameBuffer.cpp
+++ b/Widgets/FrameBuffer.cpp
@@ -90,9 +90,9 @@ RGBA32* FrameBuffer::scanline(int y)
 #endif
 }
 
+#ifdef USE_SDL
 void FrameBuffer::flush()
 {
-#ifdef USE_SDL
     SDL_UpdateWindowSurface(m_window);
-#endif
 }
+#endif
diff --git a/Widgets/FrameBuffer.h b/Widgets/FrameBuffer.h
index da00d84141..109519fba5 100644
--- a/Widgets/FrameBuffer.h
+++ b/Widgets/FrameBuffer.h
@@ -25,7 +25,11 @@ public:
 
     RGBA32* scanline(int y);
 
+#ifdef USE_SDL
     void flush();
+#else
+    void flush() { }
+#endif
 
     static void initialize();