diff --git a/uisimulator/win32/button.c b/uisimulator/win32/button.c
index a4ee5a80f8..97a57a496a 100644
--- a/uisimulator/win32/button.c
+++ b/uisimulator/win32/button.c
@@ -52,7 +52,7 @@ int button_set_release(int newmask)
 
 static int real_button_get(void)
 {
-    int btn;
+    int btn = 0;
 
     if (bActive)
     {