Crashes in Python 3.14

Traceback (most recent call last):
  File "/usr/lib/python3.14/multiprocessing/process.py", line 320, in _bootstrap
    self.run()
    ~~~~~~~~^^
  File "/usr/lib/python3.14/multiprocessing/process.py", line 108, in run
    self._target(*self._args, **self._kwargs)
    ~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/hypercorn/asyncio/run.py", line 195, in asyncio_worker
    _run(
    ~~~~^
        partial(worker_serve, app, config, sockets=sockets),
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        debug=config.debug,
        ^^^^^^^^^^^^^^^^^^^
        shutdown_trigger=shutdown_trigger,
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    )
    ^
  File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/hypercorn/asyncio/run.py", line 233, in _run
    runner.run(main(shutdown_trigger=shutdown_trigger))
    ~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/lib/python3.14/asyncio/runners.py", line 127, in run
    return self._loop.run_until_complete(task)
           ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^
  File "/usr/lib/python3.14/asyncio/base_events.py", line 719, in run_until_complete
    return future.result()
           ~~~~~~~~~~~~~^^
  File "/usr/lib/python3.14/asyncio/futures.py", line 208, in result
    raise self._exception.with_traceback(self._exception_tb)
  File "/usr/lib/python3.14/asyncio/tasks.py", line 289, in __step_run_and_handle_result
    result = coro.send(None)
  File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/hypercorn/asyncio/run.py", line 85, in worker_serve
    await lifespan.wait_for_startup()
  File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/hypercorn/asyncio/lifespan.py", line 93, in wait_for_startup
    await asyncio.wait_for(self.startup.wait(), timeout=self.config.startup_timeout)
  File "/usr/lib/python3.14/asyncio/tasks.py", line 487, in wait_for
    async with timeouts.timeout(timeout):
               ~~~~~~~~~~~~~~~~^^^^^^^^^
  File "/usr/lib/python3.14/asyncio/timeouts.py", line 88, in __aenter__
    raise RuntimeError("Timeout should be used inside a task")
RuntimeError: Timeout should be used inside a task
<sys>:0: RuntimeWarning: coroutine 'Event.wait' was never awaited
RuntimeWarning: Enable tracemalloc to get the object allocation traceback

Same thing with trio:

/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/hypercorn/trio/task_group.py:39: RuntimeWarning: coroutine 'ASGIHTTPConnection.handle_messages' was never awaited
  await config.log.exception("Error in ASGI Framework")
RuntimeWarning: Enable tracemalloc to get the object allocation traceback
Process SpawnProcess-1:
  + Exception Group Traceback (most recent call last):
  |   File "/usr/lib/python3.14/multiprocessing/process.py", line 320, in _bootstrap
  |     self.run()
  |     ~~~~~~~~^^
  |   File "/usr/lib/python3.14/multiprocessing/process.py", line 108, in run
  |     self._target(*self._args, **self._kwargs)
  |     ~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |   File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/hypercorn/trio/run.py", line 138, in trio_worker
  |     trio.run(partial(worker_serve, app, config, sockets=sockets, shutdown_trigger=shutdown_trigger))
  |     ~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |   File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/trio/_core/_run.py", line 2552, in run
  |     raise runner.main_task_outcome.error
  |   File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/hypercorn/trio/run.py", line 47, in worker_serve
  |     async with trio.open_nursery() as lifespan_nursery:
  |                ~~~~~~~~~~~~~~~~~^^
  |   File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/trio/_core/_run.py", line 1126, in __aexit__
  |     raise combined_error_from_nursery
  | ExceptionGroup: Exceptions from Trio nursery (1 sub-exception)
  +-+---------------- 1 ----------------
    | Exception Group Traceback (most recent call last):
    |   File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/hypercorn/trio/run.py", line 51, in worker_serve
    |     async with trio.open_nursery() as server_nursery:
    |                ~~~~~~~~~~~~~~~~~^^
    |   File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/trio/_core/_run.py", line 1126, in __aexit__
    |     raise combined_error_from_nursery
    | ExceptionGroup: Exceptions from Trio nursery (1 sub-exception)
    +-+---------------- 1 ----------------
      | Exception Group Traceback (most recent call last):
      |   File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/hypercorn/trio/udp_server.py", line 37, in run
      |     async with TaskGroup() as task_group:
      |                ~~~~~~~~~^^
      |   File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/hypercorn/trio/task_group.py", line 80, in __aexit__
      |     await self._nursery_manager.__aexit__(exc_type, exc_value, tb)
      |   File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/trio/_core/_run.py", line 1126, in __aexit__
      |     raise combined_error_from_nursery
      | ExceptionGroup: Exceptions from Trio nursery (1 sub-exception)
      +-+---------------- 1 ----------------
        | Traceback (most recent call last):
        |   File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/hypercorn/trio/task_group.py", line 41, in _handle
        |     await send(None)
        |   File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/hypercorn/protocol/http_stream.py", line 139, in app_send
        |     await self._send_error_response(500)
        |   File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/hypercorn/protocol/http_stream.py", line 257, in _send_error_response
        |     await self.send(EndBody(stream_id=self.stream_id))
        |   File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/hypercorn/protocol/h3.py", line 83, in stream_send
        |     self.connection.send_data(event.stream_id, b"", True)
        |     ~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        |   File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/aioquic/h3/connection.py", line 557, in send_data
        |     self._quic.send_stream_data(
        |     ~~~~~~~~~~~~~~~~~~~~~~~~~~~^
        |         stream_id, encode_frame(FrameType.DATA, data), end_stream
        |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        |     )
        |     ^
        |   File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/aioquic/quic/connection.py", line 1139, in send_stream_data
        |     stream.sender.write(data, end_stream=end_stream)
        |     ~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        |   File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/aioquic/quic/stream.py", line 334, in write
        |     assert self._reset_error_code is None, "cannot call write() after reset()"
        |            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        | AssertionError: cannot call write() after reset()
        +------------------------------------

2026-05-15 13:27:12 INFO     Running app...
2026-05-15 13:27:12 INFO     Running on https://127.0.0.1:8000 (CTRL + C to quit)
2026-05-15 13:27:12 INFO     Running on http://0.0.0.0:8080 (CTRL + C to quit)
2026-05-15 13:27:12 INFO     Running on https://0.0.0.0:4433 (QUIC) (CTRL + C to quit)
2026-05-15 13:27:13 INFO     Running on https://[::]:4433 (QUIC) (CTRL + C to quit)
2026-05-15 13:27:45 DEBUG    [f968e0c9dc50f4ba] Network path ('::1', 34404, 0, 0) discovered
2026-05-15 13:27:45 DEBUG    [f968e0c9dc50f4ba] QuicConnectionState.FIRSTFLIGHT -> QuicConnectionState.CONNECTED
2026-05-15 13:27:45 INFO     [f968e0c9dc50f4ba] Duplicate CRYPTO data received for epoch Epoch.INITIAL
2026-05-15 13:27:45 INFO     [f968e0c9dc50f4ba] Duplicate CRYPTO data received for epoch Epoch.INITIAL
2026-05-15 13:27:45 INFO     [f968e0c9dc50f4ba] Duplicate CRYPTO data received for epoch Epoch.INITIAL
2026-05-15 13:27:45 INFO     [f968e0c9dc50f4ba] Duplicate CRYPTO data received for epoch Epoch.INITIAL
2026-05-15 13:27:45 INFO     [f968e0c9dc50f4ba] Duplicate CRYPTO data received for epoch Epoch.INITIAL
2026-05-15 13:27:45 DEBUG    [f968e0c9dc50f4ba] Sending PING (probe) in packet 0
2026-05-15 13:27:45 INFO     [f968e0c9dc50f4ba] Duplicate CRYPTO data received for epoch Epoch.INITIAL
2026-05-15 13:27:45 INFO     [f968e0c9dc50f4ba] Duplicate CRYPTO data received for epoch Epoch.INITIAL
2026-05-15 13:27:45 INFO     [f968e0c9dc50f4ba] Duplicate CRYPTO data received for epoch Epoch.INITIAL
2026-05-15 13:27:45 INFO     [f968e0c9dc50f4ba] Negotiated protocol version 0x00000001 (VERSION_1)
2026-05-15 13:27:45 DEBUG    [f968e0c9dc50f4ba] TLS State.SERVER_EXPECT_CLIENT_HELLO -> State.SERVER_EXPECT_FINISHED
2026-05-15 13:27:45 DEBUG    [f968e0c9dc50f4ba] Received PING (probe) response
2026-05-15 13:27:45 DEBUG    [f968e0c9dc50f4ba] Discarding epoch Epoch.INITIAL
2026-05-15 13:27:45 DEBUG    [f968e0c9dc50f4ba] Network path ('::1', 34404, 0, 0) validated by handshake
2026-05-15 13:27:45 DEBUG    [f968e0c9dc50f4ba] TLS State.SERVER_EXPECT_FINISHED -> State.SERVER_POST_HANDSHAKE
2026-05-15 13:27:45 DEBUG    [f968e0c9dc50f4ba] Discarding epoch Epoch.HANDSHAKE
2026-05-15 13:27:45 INFO     [f968e0c9dc50f4ba] ALPN negotiated protocol h3
2026-05-15 13:27:45 DEBUG    [f968e0c9dc50f4ba] Stream 2 created by peer
2026-05-15 13:27:46 DEBUG    [f968e0c9dc50f4ba] Stream 10 created by peer
2026-05-15 13:27:46 DEBUG    [f968e0c9dc50f4ba] Stream 0 created by peer
2026-05-15 13:27:46 ERROR    Error in ASGI Framework
Traceback (most recent call last):
  File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/hypercorn/trio/task_group.py", line 28, in _handle
    await app(scope, receive, send, sync_spawn, call_soon)
  File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/hypercorn/app_wrappers.py", line 34, in __call__
    await self.app(scope, receive, send)
  File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/quart/app.py", line 1735, in __call__
    await self.asgi_app(scope, receive, send)
  File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/quart/app.py", line 1761, in asgi_app
    await asgi_handler(receive, send)
  File "/usr/src/Python/PythonRestAPI/.venv/lib/python3.14/site-packages/quart/asgi.py", line 54, in __call__
    receiver_task = asyncio.ensure_future(self.handle_messages(request, receive))
  File "/usr/lib/python3.14/asyncio/tasks.py", line 730, in ensure_future
    loop = events.get_event_loop()
  File "/usr/lib/python3.14/asyncio/events.py", line 715, in get_event_loop
    raise RuntimeError('There is no current event loop in thread %r.'
                       % threading.current_thread().name)
RuntimeError: There is no current event loop in thread 'MainThread'.

Affects me too, it seems to be caused by the asyncio.current_task() returning nothing while it should for the asyncio runtime, and this feels weird

#351

Navigation Menu

Repository navigation

Crashes in Python 3.14 #354

Metadata

Assignees

Labels

Projects

Milestone

Relationships

Development

Crashes in Python 3.14 #354

Description

Activity

khteh commented on May 15, 2026

p1-mmr commented on May 22, 2026

khteh commented on Jun 13, 2026

Metadata

Metadata

Assignees

Labels

Projects

Milestone

Relationships

Development

Issue actions