From 3af4b585527743e455145d294049c46b7c823ed9 Mon Sep 17 00:00:00 2001
From: Batuhan Taskaya <batuhanosmantaskaya@gmail.com>
Date: Fri, 30 Oct 2020 14:48:41 +0300
Subject: [PATCH] bpo-42206: Propagate and raise errors from PyAST_Validate in
 the parser (GH-23035)

---
 .../2020-10-30-13-11-01.bpo-42206.xxssR8.rst                  | 2 ++
 Parser/pegen.c                                                | 4 +++-
 2 files changed, 5 insertions(+), 1 deletion(-)
 create mode 100644 Misc/NEWS.d/next/Core and Builtins/2020-10-30-13-11-01.bpo-42206.xxssR8.rst

diff --git a/Misc/NEWS.d/next/Core and Builtins/2020-10-30-13-11-01.bpo-42206.xxssR8.rst b/Misc/NEWS.d/next/Core and Builtins/2020-10-30-13-11-01.bpo-42206.xxssR8.rst
new file mode 100644
index 00000000000..b9eb135fec5
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2020-10-30-13-11-01.bpo-42206.xxssR8.rst	
@@ -0,0 +1,2 @@
+Propagate and raise the errors caused by :c:func:`PyAST_Validate` in the
+parser.
diff --git a/Parser/pegen.c b/Parser/pegen.c
index 827d4dace1f..216edd810e2 100644
--- a/Parser/pegen.c
+++ b/Parser/pegen.c
@@ -1157,7 +1157,9 @@ _PyPegen_run_parser(Parser *p)
         p->start_rule == Py_file_input ||
         p->start_rule == Py_eval_input)
     {
-        assert(PyAST_Validate(res));
+        if (!PyAST_Validate(res)) {
+            return NULL;
+        }
     }
 #endif
     return res;