From 4d677423d77150bd4489723f5e435a2c9304f7ad Mon Sep 17 00:00:00 2001
From: Thomas Li <47963215+lithomas1@users.noreply.github.com>
Date: Sat, 22 Jan 2022 11:57:19 -0800
Subject: [PATCH 1/3] BUG: Segfault in to_json with tzaware datetime

---
 doc/source/whatsnew/v1.4.1.rst                 | 2 +-
 pandas/_libs/tslibs/src/datetime/np_datetime.c | 2 +-
 pandas/tests/io/json/test_pandas.py            | 3 ---
 3 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/doc/source/whatsnew/v1.4.1.rst b/doc/source/whatsnew/v1.4.1.rst
index f321aabc0a8a5..5dfa6651a3f30 100644
--- a/doc/source/whatsnew/v1.4.1.rst
+++ b/doc/source/whatsnew/v1.4.1.rst
@@ -23,7 +23,7 @@ Fixed regressions
 
 Bug fixes
 ~~~~~~~~~
--
+- Fixed segfault in :meth:``DataFrame.to_json`` when dumping tz-aware datetimes in Python 3.10 (:issue:`42130`)
 -
 
 .. ---------------------------------------------------------------------------
diff --git a/pandas/_libs/tslibs/src/datetime/np_datetime.c b/pandas/_libs/tslibs/src/datetime/np_datetime.c
index 9ad2ead5f919f..d861d2832b686 100644
--- a/pandas/_libs/tslibs/src/datetime/np_datetime.c
+++ b/pandas/_libs/tslibs/src/datetime/np_datetime.c
@@ -378,7 +378,7 @@ int convert_pydatetime_to_datetimestruct(PyObject *dtobj,
             if (tmp == NULL) {
                 return -1;
             }
-            seconds_offset = PyInt_AsLong(tmp);
+            seconds_offset = PyInt_AsLong(PyNumber_Long(tmp));
             if (seconds_offset == -1 && PyErr_Occurred()) {
                 Py_DECREF(tmp);
                 return -1;
diff --git a/pandas/tests/io/json/test_pandas.py b/pandas/tests/io/json/test_pandas.py
index 0b8548f98b03b..f3a6f1f80359c 100644
--- a/pandas/tests/io/json/test_pandas.py
+++ b/pandas/tests/io/json/test_pandas.py
@@ -11,7 +11,6 @@
 
 from pandas.compat import (
     IS64,
-    PY310,
     is_platform_windows,
 )
 import pandas.util._test_decorators as td
@@ -1177,7 +1176,6 @@ def test_sparse(self):
         expected = s.to_json()
         assert expected == ss.to_json()
 
-    @pytest.mark.skipif(PY310, reason="segfault GH 42130")
     @pytest.mark.parametrize(
         "ts",
         [
@@ -1195,7 +1193,6 @@ def test_tz_is_utc(self, ts):
         dt = ts.to_pydatetime()
         assert dumps(dt, iso_dates=True) == exp
 
-    @pytest.mark.skipif(PY310, reason="segfault GH 42130")
     @pytest.mark.parametrize(
         "tz_range",
         [

From c7c1983c7f5a4ece8341ab075766cff22cfa9cdc Mon Sep 17 00:00:00 2001
From: Thomas Li <47963215+lithomas1@users.noreply.github.com>
Date: Sun, 23 Jan 2022 12:23:29 -0800
Subject: [PATCH 2/3] fix memory leak?

---
 pandas/_libs/tslibs/src/datetime/np_datetime.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/pandas/_libs/tslibs/src/datetime/np_datetime.c b/pandas/_libs/tslibs/src/datetime/np_datetime.c
index d861d2832b686..b56d4367a5396 100644
--- a/pandas/_libs/tslibs/src/datetime/np_datetime.c
+++ b/pandas/_libs/tslibs/src/datetime/np_datetime.c
@@ -360,6 +360,7 @@ int convert_pydatetime_to_datetimestruct(PyObject *dtobj,
             Py_DECREF(tmp);
         } else {
             PyObject *offset;
+            PyObject *tmp_int;
             int seconds_offset, minutes_offset;
 
             /* The utcoffset function should return a timedelta */
@@ -378,11 +379,14 @@ int convert_pydatetime_to_datetimestruct(PyObject *dtobj,
             if (tmp == NULL) {
                 return -1;
             }
-            seconds_offset = PyInt_AsLong(PyNumber_Long(tmp));
+            tmp_int = PyNumber_Long(tmp);
+            seconds_offset = PyInt_AsLong(tmp_int);
             if (seconds_offset == -1 && PyErr_Occurred()) {
+                Py_DECREF(tmp_int);
                 Py_DECREF(tmp);
                 return -1;
             }
+            Py_DECREF(tmp_int);
             Py_DECREF(tmp);
 
             /* Convert to a minutes offset and apply it */

From 38b278f072c1ebb2475aeab8a634079f608bbb40 Mon Sep 17 00:00:00 2001
From: Thomas Li <47963215+lithomas1@users.noreply.github.com>
Date: Sun, 23 Jan 2022 19:26:35 -0800
Subject: [PATCH 3/3] check for null

---
 pandas/_libs/tslibs/src/datetime/np_datetime.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/pandas/_libs/tslibs/src/datetime/np_datetime.c b/pandas/_libs/tslibs/src/datetime/np_datetime.c
index b56d4367a5396..0efed210a7fdf 100644
--- a/pandas/_libs/tslibs/src/datetime/np_datetime.c
+++ b/pandas/_libs/tslibs/src/datetime/np_datetime.c
@@ -380,6 +380,10 @@ int convert_pydatetime_to_datetimestruct(PyObject *dtobj,
                 return -1;
             }
             tmp_int = PyNumber_Long(tmp);
+            if (tmp_int == NULL) {
+                Py_DECREF(tmp);
+                return -1;
+            }
             seconds_offset = PyInt_AsLong(tmp_int);
             if (seconds_offset == -1 && PyErr_Occurred()) {
                 Py_DECREF(tmp_int);