[Python-Dev] How to debug pyexpat SIGSEGV with GDB?

[Christian Tismer]

Brad Clements wrote:

> Sorry if this is OT.
> 
> I've hit a repeatable segfault in pyexpat on RH Linux 9 with Python 2.3.3 (I'm trying 
> rss2email).
> 
> It seems that XML_parse is returning an error, but when XML_GetCurrentLineNumber 
> is called positionPtr is not valid.
> 
> I catch this in GDB and have looked at the stack (see below), but when I get back up 
> the stack into PyCFunction_Call  I don't know what to do.
> 
> Ideally, I want to find out the Python source file and line number that is currently being 
> executed, then look at the Python source to figure out exactly which pyexpat call is 
> being made just before the call to get_parse_result.
> 
> It seems strange that (it appears) that Python code is calling  get_parse_result directly.
> 
> So, how can I figure out where in the Python source the function call is coming from 
> using gdb? I'm sure it involves "print" and some casts.. I couldn't find a howto on 
> python.org

Just as a wild idea:

Could this be related to the fact that Python 2.3.3 doesn't
maintain explicit line numbers, any longer?

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