diff --git a/src/proto/if_tcl.pro b/src/proto/if_tcl.pro
index 0679ed4..2af9174 100644
--- a/src/proto/if_tcl.pro
+++ b/src/proto/if_tcl.pro
@@ -1,10 +1,10 @@
 /* if_tcl.c */
-void vim_tcl_init __ARGS((char *arg));
-int tcl_enabled __ARGS((int verbose));
-void tcl_end __ARGS((void));
-void ex_tcl __ARGS((exarg_T *eap));
-void ex_tclfile __ARGS((exarg_T *eap));
-void ex_tcldo __ARGS((exarg_T *eap));
-void tcl_buffer_free __ARGS((buf_T *buf));
-void tcl_window_free __ARGS((win_T *win));
+extern void vim_tcl_init __ARGS((char *arg));
+extern int tcl_enabled __ARGS((int verbose));
+extern void tcl_end __ARGS((void));
+extern void ex_tcl __ARGS((exarg_T *eap));
+extern void ex_tclfile __ARGS((exarg_T *eap));
+extern void ex_tcldo __ARGS((exarg_T *eap));
+extern void tcl_buffer_free __ARGS((buf_T *buf));
+extern void tcl_window_free __ARGS((win_T *win));
 /* vim: set ft=c : */