ElementTree parsing bus error (but only from mod_python)

[kathyvs]

BPO	2951
Nosy	@jackdied, @benjaminp

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

Show more details

GitHub fields:

assignee = None
closed_at = <Date 2008-08-01.21:01:17.386>
created_at = <Date 2008-05-23.17:59:37.914>
labels = ['OS-mac', 'invalid', 'library', 'type-crash']
title = 'ElementTree parsing bus error (but only from mod_python)'
updated_at = <Date 2008-08-01.21:01:17.376>
user = 'https://bugs.python.org/kathyvs'

bugs.python.org fields:

activity = <Date 2008-08-01.21:01:17.376>
actor = 'jackdied'
assignee = 'none'
closed = True
closed_date = <Date 2008-08-01.21:01:17.386>
closer = 'jackdied'
components = ['Library (Lib)', 'macOS']
creation = <Date 2008-05-23.17:59:37.914>
creator = 'kathyvs'
dependencies = []
files = []
hgrepos = []
issue_num = 2951
keywords = []
message_count = 5.0
messages = ['67259', '70045', '70046', '70047', '70592']
nosy_count = 4.0
nosy_names = ['jackdied', 'kathyvs', 'benjamin.peterson', 'nicodotti']
pr_nums = []
priority = 'normal'
resolution = 'not a bug'
stage = None
status = 'closed'
superseder = None
type = 'crash'
url = 'https://bugs.python.org/issue2951'
versions = ['Python 2.5']

[kathyvs]

The follow code works fine when run directly. It crashes (with a bus
error) if used as a mod_python handler. It doesn't crash if ElementTree
is replaced with cElementTree.

from xml.etree import ElementTree as eltree

def handler(req):
    body = """<?xml version='1.0' encoding='utf-8'?>
<collection uuid="~01edc22c1628e711ddb20220296b032019"
href="http://localhost:8888/ws/dataset/~01edc22c1628e711ddb20220296b032019">
  <name>Service_offerings query at 2008-05-23 12:47:28.038233</name>
</collection>"""

    response_elem = eltree.XML(body)
    return 0

I don't know if this a mod_python or ElementTree issue, but it looks
more like an ElementTree problem.

[nicodotti]

Thanks for logging this bug Kathy I had the same problem for 2 days! I
used the cElementTree as you mentioned and it worked fine

[benjaminp]

This is probably a mod_python problem.

[kathyvs]

Does ElementTree do anything unusual in importing? That is one area
where mod_python is different from standard python.

[jackdied]

It is a common apache problem. Elementree imports an expat parser
(presumably cElementree doesn't) and different versions of expat play
together very poorly. Lots of apache modules load one xml lib version
or another and they tend to step on each others toes .. and then segfault.

IIRC the only way to resolve this is to figure out which loaded apache
modules are using expat and recompile them all against the same version.
Not fun.