Short demo program illustrating Kivy bug

hang_on_terminate.py

import logging
import multiprocessing

multiprocessing.log_to_stderr().setLevel(logging.DEBUG)

import kivy
from kivy.app import App
from kivy.uix.button import Button


class MyApp(App):
    def build(self):
        return Button(text='foo', on_touch_down=self.runpool)

    def runpool(self, *args):
        pool = multiprocessing.Pool()
        pool.terminate()


if __name__ == "__main__":
    MyApp().run()