diff --git a/vncviewer/OptionsDialog.h b/vncviewer/OptionsDialog.h
index a6b504e..39bd7af 100644
--- a/vncviewer/OptionsDialog.h
+++ b/vncviewer/OptionsDialog.h
@@ -107,7 +107,9 @@
   Fl_Check_Button *viewOnlyCheckbox;
   Fl_Check_Button *acceptClipboardCheckbox;
   Fl_Check_Button *sendClipboardCheckbox;
+#if !defined(WIN32) && !defined(__APPLE__)
   Fl_Check_Button *sendPrimaryCheckbox;
+#endif
   Fl_Check_Button *systemKeysCheckbox;
   Fl_Choice *menuKeyChoice;