diff --git a/src/eval.c b/src/eval.c
index a49d54b..7b8a0ae 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -15773,6 +15773,7 @@
 		listitem_T *li3 = li2->li_next;
 		listitem_T *li4 = li3->li_next;
 
+		vim_free(li1->li_tv.vval.v_string);
 		li1->li_tv.vval.v_string = vim_strnsave(regmatch.startp[0],
 				(int)(regmatch.endp[0] - regmatch.startp[0]));
 		li3->li_tv.vval.v_number =