I am using the latest master branch of the git repo https://github.com/celery/librabbitmq and installing librabbitmq==2.0.0 for Python 3.6 by following the instructions in the readme

Using the development version

You can clone the repository by doing the following:

$ git clone git://github.com/celery/librabbitmq.git

Then install it by doing the following:

$ cd librabbitmq
$ make install        # or make develop

This works fine (after installing certain binaries for c compliation in the OS), but when I then make a small a+b add task and call it with add.delay(2,2) it fails with the following error. I looked up and saw that Celery 4 uses json as serializer, so clearly it is not because if pickle serialization

1. Changing from librabbitmq to pyamqp broker works normally
2. Same exact situation in both MacOS and Ubuntu 16

[2018-04-30 23:40:02,956: CRITICAL/MainProcess] Unrecoverable error:
SystemError('<built-in method _basic_recv of Connection object at
0x1099ec5e8> returned a result with an error set',) Traceback (most
recent call last): File
"/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/kombu/messaging.py",
line 624, in _receive_callback
return on_m(message) if on_m else self.receive(decoded, message) File
"/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/celery/worker/consumer/consumer.py",
line 570, in on_task_received
callbacks, File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/celery/worker/strategy.py",
line 145, in task_message_handler
handle(req) File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/celery/worker/worker.py",
line 221, in _process_task_sem
return self._quick_acquire(self._process_task, req) File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/kombu/async/semaphore.py",
line 62, in acquire
callback(*partial_args, **partial_kwargs) File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/celery/worker/worker.py",
line 226, in _process_task
req.execute_using_pool(self.pool) File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/celery/worker/request.py",
line 531, in execute_using_pool
correlation_id=task_id, File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/celery/concurrency/base.py",
line 155, in apply_async
**options) File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/billiard/pool.py",
line 1486, in apply_async
self._quick_put((TASK, (result._job, None, func, args, kwds))) File
"/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/celery/concurrency/asynpool.py",
line 813, in send_job
body = dumps(tup, protocol=protocol) TypeError: can't pickle memoryview objects

The above exception was the direct cause of the following exception:

Traceback (most recent call last): File
"/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/celery/worker/worker.py",
line 203, in start
self.blueprint.start(self) File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/celery/bootsteps.py",
line 119, in start
step.start(parent) File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/celery/bootsteps.py",
line 370, in start
return self.obj.start() File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/celery/worker/consumer/consumer.py",
line 320, in start
blueprint.start(self) File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/celery/bootsteps.py",
line 119, in start
step.start(parent) File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/celery/worker/consumer/consumer.py",
line 596, in start
c.loop(*c.loop_args()) File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/celery/worker/loops.py",
line 88, in asynloop
next(loop) File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/kombu/async/hub.py",
line 354, in create_loop
cb(*cbargs) File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/kombu/transport/base.py",
line 236, in on_readable
reader(loop) File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/kombu/transport/base.py",
line 218, in _read
drain_events(timeout=0) File "/Users/somghosh/.virtualenvs/ctdb/lib/python3.6/site-packages/librabbitmq-2.0.0-py3.6-macosx-10.6-intel.egg/librabbitmq/init.py",
line 227, in drain_events
self._basic_recv(timeout) SystemError: <built-in method _basic_recv of Connection object at 0x1099ec5e8> returned a result with an error set