PyPy3.7 compatability

[olliemath]

• gevent version: 21.1.2
• Python version: PyPy 3.7-7.3.4
• Operating System: Linux

Description:

Currently I'm trying to get the following snippet to work with the latest pypy (3.7-7.3.4), however it hangs forever

import gevent
from gevent import socket

def get():
   socket.gethostbyname('www.python.org')

g = gevent.spawn(get)
g.join()

Right now this is as far as I've been able to dig, so unsure whether this is an issue with pypy or gevent (or just a general incompatibility) the snippet works in cpython, pypy3.6, and with equivalent eventlet code. A keyboard interupt gets us

^CTraceback (most recent call last):
  File "/home/oliver/gevent/venv/site-packages/gevent/libev/corecffi.py", line 58, in python_check_callback
    pass
KeyboardInterrupt
2021-04-16T23:28:51Z
Traceback (most recent call last):
  File "gsockets.py", line 11, in <module>
    g.join()
  File "/home/oliver/gevent/venv/site-packages/gevent/greenlet.py", line 846, in join
    result = get_my_hub(self).switch() # pylint:disable=undefined-variable
  File "/home/oliver/gevent/venv/site-packages/gevent/_greenlet_primitives.py", line 65, in switch
    return _greenlet_switch(self) # pylint:disable=undefined-variable
  File "/usr/lib/pypy3/lib_pypy/greenlet.py", line 63, in switch
    return self.__switch('switch', (args, kwds))
  File "/usr/lib/pypy3/lib_pypy/greenlet.py", line 104, in __switch
    args, kwds = unbound_method(current, *baseargs, to=target)
  File "/home/oliver/gevent/venv/site-packages/gevent/libev/corecffi.py", line 58, in python_check_callback
    pass
KeyboardInterrupt

Here is a minimal dockerfile if you'd like to reproduce:

FROM pypy:3.7-7.3.4
RUN pip3 install gevent==21.1.2
RUN printf "import gevent\nfrom gevent import socket\ndef get():\n  socket.gethostbyname('www.python.org')\ng = gevent.spawn(get)\ng.join()" > app.py
RUN pypy3 app.py  # <- hangs forever

Other things I've tried

As above, but replaced with a sleep works fine:

import gevent
from gevent import sleep

def snooze():
    sleep(1)

g = gevent.spawn(snooze)
g.join()  # <- returns fine

As above, but with monkey-patched stdlib does not work:

from gevent import monkey
monkey.patch_all()

import socket
import threading

def get():
    socket.gethostbyname('www.python.org')

t = threading.Thread(target=get)
t.start()
t.join()  # Hangs forever

[jamadden]

Thank you for the report. I noticed this on another project of mine today, I just haven't had a chance to dig into it yet.

[jamadden]

This was identified as a bug in PyPy and should be fixed in the next release.

[mattip]

For reference, the PyPy bugfix release 7.3.5 (released 5.23.21, should be on conda soon) should have fixed this.

[olliemath]

The 7.3.5 release does fix this, thanks!