fix memleak in str_parse_eval
diff --git a/libkc3/str.c b/libkc3/str.c
index 016b5ec..4c3bbb5 100644
--- a/libkc3/str.c
+++ b/libkc3/str.c
@@ -663,7 +663,7 @@ bool str_parse_eval (const s_str *str, s_tag *dest)
goto next;
tag_init_call_cast(&tag, &g_sym_Str);
arg = &list_next(tag.data.call.arguments)->tag;
- tag_init_copy(arg, &l->tag);
+ *arg = l->tag;
l->tag = tag;
next:
l = list_next(l);