Re: [Matplotlib-users] Segmentation fault from inside transforms

[Todd M. <jm...@st...>]

On Thu, 2004-10-21 at 16:00, John Hunter wrote:
> >>>>> "Ted" == Ted Drain <ted...@jp...> writes:
> 
>     Ted> I'm trying to build matplotlib and I'm getting a segmentation
>     Ted> fault when I do: from matplotlib import *
> 
>     Ted> I've traced the fault down to the transforms module.
> 
>     Ted> My first attempt used: gcc 3.3.2 Python 2.3.3 numarray 1.1
>     Ted> gdmodule 0.52 gd 2.0.28 freetype 2.1.9 agg 22 matplotlib
>     Ted> 0.63.4
> 
> Standard issue stuff - very close to what most people are using w/o
> incident.  Hmmmm....
> 
>     Ted> In this version _na_transform segementation faults at this
>     Ted> line: static _transforms_module* _transforms = new
>     Ted> _transforms_module;
> 
>     Ted> I traced the fault down to the ExtensionModuleBaseClass where
>     Ted> it attempts to call: __Py_PackageContext()
> 
>     Ted> It looks to me like this function is trying to access the
>     Ted> variable (which it dereferences WITHOUT checking for a null
>     Ted> pointer).  static char **ptr__Py_PackageContext = NULL;
> 
> Could you try editing it an adding the NULL test; if this works can
> you submit a patch pack to be and a bug report to the pycxx sf site?
> 
>     Ted> This ptr gets init'ed in the function
>     Ted> InitialisePythonIndirectInterface() but I can't find anywhere
>     Ted> that function is being called.
> 
>     Ted> FYI: I also tried matplotlib 0.62.4 and I get the same error.
> 
> It couldn't be the exact same error, because _na_transforms did not
> exist in 0.62.4.  Do you mean that you got a segfault on the same line
> in _transform?

Check for matplotlib/_transforms.so left over from prior installations
and blow away your old matplotlib and re-install if you find it.  Before
you re-install, also blow away matplotlib/build.

Todd