diff --git a/src/proto/if_python.pro b/src/proto/if_python.pro
index 793b6ee..09c4ab7 100644
--- a/src/proto/if_python.pro
+++ b/src/proto/if_python.pro
@@ -1,8 +1,8 @@
 /* if_python.c */
-int python_enabled __ARGS((int verbose));
-void python_end __ARGS((void));
-void ex_python __ARGS((exarg_T *eap));
-void ex_pyfile __ARGS((exarg_T *eap));
-void python_buffer_free __ARGS((buf_T *buf));
-void python_window_free __ARGS((win_T *win));
+extern int python_enabled __ARGS((int verbose));
+extern void python_end __ARGS((void));
+extern void ex_python __ARGS((exarg_T *eap));
+extern void ex_pyfile __ARGS((exarg_T *eap));
+extern void python_buffer_free __ARGS((buf_T *buf));
+extern void python_window_free __ARGS((win_T *win));
 /* vim: set ft=c : */