diff --git a/Python/pythonmain.c b/Python/pythonmain.c
index ac1d86a..48ccd38 100644
--- a/Python/pythonmain.c
+++ b/Python/pythonmain.c
@@ -33,7 +33,7 @@
 /* Interface to getopt(): */
 extern int optind;
 extern char *optarg;
-extern int getopt PROTO((int, char **, char *));
+extern int getopt(); /* PROTO((int, char **, char *)); -- not standardized */
 
 extern char *getenv();