diff --git a/src/drawline.c b/src/drawline.c
index 666e32d..7b16457 100644
--- a/src/drawline.c
+++ b/src/drawline.c
@@ -1524,7 +1524,7 @@
 			if (p != NULL)
 			{
 			    p_extra = p;
-			    n_extra = STRLEN(p);
+			    n_extra = (int)STRLEN(p);
 			    extra_attr = used_attr;
 			    n_attr = n_extra;
 			    text_prop_attr = 0;