Merge branch 'main' into fix-json-tool

Author: mpkocher

Include/cpython/pystate.h

@@ -157,6 +157,11 @@ struct _ts {
      */
     unsigned long native_thread_id;
 
+    /* List of objects that still need to be cleaned up, singly linked
+     * via their gc headers' gc_next pointers. The list is populated by
+     * _PyTrash_thread_deposit_object and cleaned up by
+     * _PyTrash_thread_destroy_chain.
+     */
     PyObject *delete_later;
 
     /* Tagged pointer to top-most critical section, or zero if there is no

Include/internal/pycore_interp_structs.h

@@ -203,12 +203,6 @@ enum _GCPhase {
 #define NUM_GENERATIONS 3
 
 struct _gc_runtime_state {
-    /* List of objects that still need to be cleaned up, singly linked
-     * via their gc headers' gc_prev pointers.  */
-    PyObject *trash_delete_later;
-    /* Current call-stack depth of tp_dealloc calls. */
-    int trash_delete_nesting;
-
     /* Is automatic collection enabled? */
     int enabled;
     int debug;

Lib/multiprocessing/dummy/__init__.py

@@ -33,7 +33,7 @@
 
 class DummyProcess(threading.Thread):
 
-    def __init__(self, group=None, target=None, name=None, args=(), kwargs={}):
+    def __init__(self, group=None, target=None, name=None, args=(), kwargs=None):
         threading.Thread.__init__(self, group, target, name, args, kwargs)
         self._pid = None
         self._children = weakref.WeakKeyDictionary()

Lib/multiprocessing/process.py

@@ -77,7 +77,7 @@ class BaseProcess(object):
     def _Popen(self):
         raise NotImplementedError
 
-    def __init__(self, group=None, target=None, name=None, args=(), kwargs={},
+    def __init__(self, group=None, target=None, name=None, args=(), kwargs=None,
                  *, daemon=None):
         assert group is None, 'group argument must be None for now'
         count = next(_process_counter)
@@ -89,7 +89,7 @@ def __init__(self, group=None, target=None, name=None, args=(), kwargs={},
         self._closed = False
         self._target = target
         self._args = tuple(args)
-        self._kwargs = dict(kwargs)
+        self._kwargs = dict(kwargs) if kwargs else {}
         self._name = name or type(self).__name__ + '-' + \
                      ':'.join(str(i) for i in self._identity)
         if daemon is not None:

Lib/test/_test_multiprocessing.py

@@ -5278,6 +5278,23 @@ def test_invalid_handles(self):
                           multiprocessing.connection.Connection, -1)
 
 
+#
+# Regression tests for BaseProcess kwargs handling
+#
+
+class TestBaseProcessKwargs(unittest.TestCase):
+    def test_default_kwargs_not_shared_between_instances(self):
+        # Creating multiple Process instances without passing kwargs
+        # must create independent empty dicts (no shared state).
+        p1 = multiprocessing.Process(target=lambda: None)
+        p2 = multiprocessing.Process(target=lambda: None)
+        self.assertIsInstance(p1._kwargs, dict)
+        self.assertIsInstance(p2._kwargs, dict)
+        self.assertIsNot(p1._kwargs, p2._kwargs)
+        # Mutating one should not affect the other
+        p1._kwargs['x'] = 1
+        self.assertNotIn('x', p2._kwargs)
+
 
 @hashlib_helper.requires_hashdigest('sha256')
 class OtherTest(unittest.TestCase):

Lib/test/test_math.py

@@ -1485,7 +1485,9 @@ def __rmul__(self, other):
 
         # Error cases that arose during development
         args = ((-5, -5, 10), (1.5, 4611686018427387904, 2305843009213693952))
-        self.assertEqual(sumprod(*args), 0.0)
+        self.assertEqual(sumprod(*args), -7.5)
+        self.assertEqual(sumprod([-0.01, 1, -1, 0.01], [1, 1, 1, 1]), 0.0)
+        self.assertEqual(sumprod([1, 1, 1, 1], [-0.01, 1, -1, 0.01], ), 0.0)
 
     @requires_IEEE_754
     @unittest.skipIf(HAVE_DOUBLE_ROUNDING,

Misc/NEWS.d/next/Core_and_Builtins/2025-09-17-13-21-26.gh-issue-139074.dVZO5F.rst

@@ -0,0 +1,2 @@
+Fixed a missing case in :func:`math.sumprod` where a low precision path was
+taken when an int/int input pair followed a float input.

Misc/NEWS.d/next/Library/2025-09-17-08-32-43.gh-issue-138813.LHkHjX.rst

@@ -0,0 +1 @@
+:class:`!multiprocessing.BaseProcess` defaults ``kwargs`` to ``None`` instead of a shared dictionary.

Modules/mathmodule.c

@@ -2937,32 +2937,31 @@ math_sumprod_impl(PyObject *module, PyObject *p, PyObject *q)
 
             if (!finished) {
                 double flt_p, flt_q;
-                bool p_type_float = PyFloat_CheckExact(p_i);
-                bool q_type_float = PyFloat_CheckExact(q_i);
-                if (p_type_float && q_type_float) {
-                    flt_p = PyFloat_AS_DOUBLE(p_i);
-                    flt_q = PyFloat_AS_DOUBLE(q_i);
-                } else if (p_type_float && (PyLong_CheckExact(q_i) || PyBool_Check(q_i))) {
-                    /* We care about float/int pairs and int/float pairs because
-                       they arise naturally in several use cases such as price
-                       times quantity, measurements with integer weights, or
-                       data selected by a vector of bools. */
+
+                if (PyFloat_CheckExact(p_i)) {
                     flt_p = PyFloat_AS_DOUBLE(p_i);
-                    flt_q = PyLong_AsDouble(q_i);
-                    if (flt_q == -1.0 && PyErr_Occurred()) {
+                } else if (PyLong_CheckExact(p_i) || PyBool_Check(p_i)) {
+                    flt_p = PyLong_AsDouble(p_i);
+                    if (flt_p == -1.0 && PyErr_Occurred()) {
                         PyErr_Clear();
                         goto finalize_flt_path;
                     }
-                } else if (q_type_float && (PyLong_CheckExact(p_i) || PyBool_Check(p_i))) {
+                } else {
+                    goto finalize_flt_path;
+                }
+
+                if (PyFloat_CheckExact(q_i)) {
                     flt_q = PyFloat_AS_DOUBLE(q_i);
-                    flt_p = PyLong_AsDouble(p_i);
-                    if (flt_p == -1.0 && PyErr_Occurred()) {
+                } else if (PyLong_CheckExact(q_i) || PyBool_Check(q_i)) {
+                    flt_q = PyLong_AsDouble(q_i);
+                    if (flt_q == -1.0 && PyErr_Occurred()) {
                         PyErr_Clear();
                         goto finalize_flt_path;
                     }
                 } else {
                     goto finalize_flt_path;
                 }
+
                 TripleLength new_flt_total = tl_fma(flt_p, flt_q, flt_total);
                 if (isfinite(new_flt_total.hi)) {
                     flt_total = new_flt_total;

Objects/object.c

@@ -3051,7 +3051,7 @@ Py_ReprLeave(PyObject *obj)
 
 /* Trashcan support. */
 
-/* Add op to the gcstate->trash_delete_later list.  Called when the current
+/* Add op to the tstate->delete_later list.  Called when the current
  * call-stack depth gets large.  op must be a gc'ed object, with refcount 0.
  *  Py_DECREF must already have been called on it.
  */
@@ -3077,7 +3077,7 @@ _PyTrash_thread_deposit_object(PyThreadState *tstate, PyObject *op)
     tstate->delete_later = op;
 }
 
-/* Deallocate all the objects in the gcstate->trash_delete_later list.
+/* Deallocate all the objects in the tstate->delete_later list.
  * Called when the call-stack unwinds again. */
 void
 _PyTrash_thread_destroy_chain(PyThreadState *tstate)