gh-71587: Drop local reference cache to _strptime module in _datetime

Include/internal/pycore_global_strings.h

@@ -266,6 +266,7 @@ struct _Py_global_strings {
         STRUCT_FOR_ID(_showwarnmsg)
         STRUCT_FOR_ID(_shutdown)
         STRUCT_FOR_ID(_slotnames)
+        STRUCT_FOR_ID(_strptime)
         STRUCT_FOR_ID(_strptime_datetime)
         STRUCT_FOR_ID(_swappedbytes_)
         STRUCT_FOR_ID(_type_)

Lib/test/test_embed.py

@@ -404,6 +404,15 @@ def test_ucnhash_capi_reset(self):
         out, err = self.run_embedded_interpreter("test_repeated_init_exec", code)
         self.assertEqual(out, '9\n' * INIT_LOOPS)
 
+    def test_datetime_reset_strptime(self):
+        code = (
+            "import datetime;"
+            "d = datetime.datetime.strptime('2000-01-01', '%Y-%m-%d');"
+            "print(d.strftime('%Y%m%d'))"
+        )
+        out, err = self.run_embedded_interpreter("test_repeated_init_exec", code)
+        self.assertEqual(out, '20000101\n' * INIT_LOOPS)
+
 
 @unittest.skipIf(_testinternalcapi is None, "requires _testinternalcapi")
 class InitConfigTests(EmbeddingTestsMixin, unittest.TestCase):

Misc/NEWS.d/next/Library/2024-06-07-11-23-31.gh-issue-71587.IjFajE.rst

@@ -0,0 +1,2 @@
+Fix crash in C version of :meth:`datetime.datetime.strptime` when called again
+on the restarted interpreter.

Modules/_datetimemodule.c

@@ -5514,19 +5514,19 @@ datetime_utcfromtimestamp(PyObject *cls, PyObject *args)
 static PyObject *
 datetime_strptime(PyObject *cls, PyObject *args)
 {
-    static PyObject *module = NULL;
-    PyObject *string, *format;
+    PyObject *string, *format, *result;
 
     if (!PyArg_ParseTuple(args, "UU:strptime", &string, &format))
         return NULL;
 
+    PyObject *module = PyImport_Import(&_Py_ID(_strptime));
     if (module == NULL) {
-        module = PyImport_ImportModule("_strptime");
-        if (module == NULL)
-            return NULL;
+        return NULL;
     }
-    return PyObject_CallMethodObjArgs(module, &_Py_ID(_strptime_datetime),
-                                         cls, string, format, NULL);
+    result = PyObject_CallMethodObjArgs(module, &_Py_ID(_strptime_datetime),
+                                        cls, string, format, NULL);
+    Py_DECREF(module);
+    return result;
 }
 
 /* Return new datetime from date/datetime and time arguments. */

Tools/c-analyzer/cpython/globals-to-fix.tsv

@@ -393,7 +393,6 @@ Modules/xxmodule.c	-	ErrorObject	-
 
 ## initialized once
 Modules/_cursesmodule.c	-	ModDict	-
-Modules/_datetimemodule.c	datetime_strptime	module	-
 
 ## state
 Modules/_datetimemodule.c	-	_datetime_global_state	-