Segmentation fault on unrelated Python exceptions

I’d like to use pyosmium using Python 3.6.2. When running the following example code (based on https://github.com/osmcode/pyosmium/blob/master/examples/osm_file_stats.py ) using Python 3, I get a Segmentation fault (core dumped) message (caused by the last line of code) with no additional info. However, running the same code using Python 2.7.15+, gives me a proper error message.

My question is not about this specific example, but about the combination of python3 and pyosmium in general: How would I debug such errors (and why aren’t any proper error messages displayed)?

import osmium as o
import sys

class FileStatsHandler(o.SimpleHandler):

    def __init__(self):
        super(FileStatsHandler, self).__init__()
        self.nodes = 0

    def node(self, n):
        self.nodes += 1

if __name__ == '__main__':
    if len(sys.argv) != 2:
        print("Usage: python osm_file_stats.py <osmfile>")
        sys.exit(-1)

    h = FileStatsHandler()

    h.apply_file(sys.argv[1])

    print("Nodes: %d" % h.nodes)
    print("Nodes: " + h.nodes) # XXX: h.nodes should be str(h.nodes)

[lonvia]

We’ve found the culprit. Ubuntu’s apport installs a special exception handler which segfaults when trying to handle the exception. The workaround is to simply uninstall it: sudo apt-get remove python3-apport

I wouldn’t rule out that there is something wrong with the way we build the binaries that makes apport fail or that some resources are not properly freed but I’m at a loss how to debug that.

[lonvia]

manylinux2020 binaries are now available. Be aware that a recent version of pip is necessary. The one that is shipped with Ubuntu is too old.