diff --git a/TODO.md b/TODO.md
index 29751481..23fd7bd1 100644
--- a/TODO.md
+++ b/TODO.md
@@ -15,6 +15,7 @@
 * State Machine
 * Issues:
     * `prop A : A = x {}` doesn't report error (because type A should resolve to the property itself)
+    * `func X(x : NotExists) : void;` crashes
 
 #### (probably not do)