diff --git a/usr.bin/yacc/main.c b/usr.bin/yacc/main.c
index 0e7bb3ff6e0e..06b55bbab9bb 100644
--- a/usr.bin/yacc/main.c
+++ b/usr.bin/yacc/main.c
@@ -485,9 +485,7 @@ open_files()
 
 
 int
-main(argc, argv)
-int argc;
-char *argv[];
+main(int argc, char *argv[])
 {
     set_signals();
     getargs(argc, argv);