update ast

diff --git a/ast b/ast
index 1f60e2df75ddd542a0cdf1853c37d5b685bf9641..569a22fbd74bc34812cfd4ab08a4f12a8f94edb4 160000 (submodule)
--- a/ast
+++ b/ast
@@ -1 +1 @@
-Subproject commit 1f60e2df75ddd542a0cdf1853c37d5b685bf9641
+Subproject commit 569a22fbd74bc34812cfd4ab08a4f12a8f94edb4