This argument isn't used or supplied.

--- ibp-0.21/xdisp.c	2000-09-29 23:11:53.000000000 +0100
+++ ibp-0.21/xdisp.c	2025-07-04 18:18:35.542070912 +0100
@@ -549,7 +549,7 @@
 
 
 struct sunclock *
-makeClockContext(wid, ht, win, pix, gc)
+makeClockContext(wid, ht, win, pix)
 int				wid;
 int				ht;
 Window				win;