From 5833e94d8615ea18b14e4830ecdb868aec81b378 Mon Sep 17 00:00:00 2001
From: Pablo Galindo <Pablogsal@gmail.com>
Date: Sat, 11 May 2019 20:54:37 +0100
Subject: [PATCH] bpo-36817: Fix reference leak for expr_text in f-string =
 parsing (GH-13249)

---
 Python/ast.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/Python/ast.c b/Python/ast.c
index 21abd7e88d8..585f8b3fba4 100644
--- a/Python/ast.c
+++ b/Python/ast.c
@@ -5228,10 +5228,15 @@ fstring_find_expr(const char **str, const char *end, int raw, int recurse_lvl,
 
     }
     if (equal_flag) {
-        Py_ssize_t len = expr_text_end-expr_start;
+        Py_ssize_t len = expr_text_end - expr_start;
         expr_text = PyUnicode_FromStringAndSize(expr_start, len);
-        if (!expr_text)
+        if (!expr_text) {
             goto error;
+        }
+        if (PyArena_AddPyObject(c->c_arena, expr_text) < 0) {
+            Py_DECREF(expr_text);
+            goto error;
+        }
     }
 
     /* Check for the format spec, if present. */