From 8f7c4f1cefe63d15cc53e559da12ae3388aa74cd Mon Sep 17 00:00:00 2001 From: Savannah Ostrowski Date: Wed, 17 Dec 2025 12:04:53 -0800 Subject: [PATCH] =?UTF-8?q?[3.13]=20GH-100964:=20Fix=20reference=20cycle?= =?UTF-8?q?=20in=20exhausted=20generator=20frames=20(G=E2=80=A6=20(#142904?= =?UTF-8?q?)?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit * [3.13] GH-100964: Fix reference cycle in exhausted generator frames (GH-141112) (cherry picked from commit 92243dc62ce10715ab0d9074b23dea5a1bfa9dcc) Co-authored-by: Savannah Ostrowski --- Lib/test/test_generators.py | 12 ++++++++++++ .../2025-11-06-05-21-25.gh-issue-100964.TxPf1b.rst | 1 + Python/ceval.c | 2 +- 3 files changed, 14 insertions(+), 1 deletion(-) create mode 100644 Misc/NEWS.d/next/Core and Builtins/2025-11-06-05-21-25.gh-issue-100964.TxPf1b.rst diff --git a/Lib/test/test_generators.py b/Lib/test/test_generators.py index d6014fd9d63..7aa4458fc71 100644 --- a/Lib/test/test_generators.py +++ b/Lib/test/test_generators.py @@ -112,6 +112,18 @@ def g3(): return (yield from f()) gen.send(2) self.assertEqual(cm.exception.value, 2) + def test_exhausted_generator_frame_cycle(self): + def g(): + yield + + generator = g() + frame = generator.gi_frame + self.assertIsNone(frame.f_back) + next(generator) + self.assertIsNone(frame.f_back) + next(generator, None) + self.assertIsNone(frame.f_back) + class GeneratorTest(unittest.TestCase): diff --git a/Misc/NEWS.d/next/Core and Builtins/2025-11-06-05-21-25.gh-issue-100964.TxPf1b.rst b/Misc/NEWS.d/next/Core and Builtins/2025-11-06-05-21-25.gh-issue-100964.TxPf1b.rst new file mode 100644 index 00000000000..7c554cf8dda --- /dev/null +++ b/Misc/NEWS.d/next/Core and Builtins/2025-11-06-05-21-25.gh-issue-100964.TxPf1b.rst @@ -0,0 +1 @@ +Fix reference cycle in exhausted generator frames. Patch by Savannah Ostrowski. diff --git a/Python/ceval.c b/Python/ceval.c index 0be6c57c1cf..301cc3b2b90 100644 --- a/Python/ceval.c +++ b/Python/ceval.c @@ -1696,10 +1696,10 @@ clear_gen_frame(PyThreadState *tstate, _PyInterpreterFrame * frame) gen->gi_exc_state.previous_item = NULL; tstate->c_recursion_remaining--; assert(frame->frame_obj == NULL || frame->frame_obj->f_frame == frame); + frame->previous = NULL; _PyFrame_ClearExceptCode(frame); _PyErr_ClearExcState(&gen->gi_exc_state); tstate->c_recursion_remaining++; - frame->previous = NULL; } void