diff --git a/src/mark.c b/src/mark.c
index 0265160..194125e 100644
--- a/src/mark.c
+++ b/src/mark.c
@@ -695,7 +695,7 @@
 	return NULL;
     /* Truncate the line to fit it in the window */
     len = 0;
-    for (p = s; *p != NUL; mb_ptr_adv(p))
+    for (p = s; *p != NUL; MB_PTR_ADV(p))
     {
 	len += ptr2cells(p);
 	if (len >= Columns - lead_len)