Fix a few compiler warnings.
diff --git a/src/proto.h b/src/proto.h
index 01db689..c39f7f0 100644
--- a/src/proto.h
+++ b/src/proto.h
@@ -277,6 +277,13 @@
#ifdef MACOS_CONVERT
# include "os_mac_conv.pro"
#endif
+#if defined(MACOS_X_UNIX) && defined(FEAT_CLIPBOARD) && !defined(FEAT_GUI)
+/* functions in os_macosx.m */
+void clip_mch_lose_selection(VimClipboard *cbd);
+int clip_mch_own_selection(VimClipboard *cbd);
+void clip_mch_request_selection(VimClipboard *cbd);
+void clip_mch_set_selection(VimClipboard *cbd);
+#endif
#ifdef __BORLANDC__
# define _PROTO_H