[C++-SIG] Python calling C++ issues

[David Beazley]

Duncan Grisby writes:
> 
> I haven't particularly followed the discussion, but I just want to
> point out that doing what you suggest is extremely dangerous. There is
> no guarantee that longs are the same size as pointers. 

With the notable exception of pointers to members, since when has a
long never been large enough to hold a pointer value?  Can you name a
specific instance where this doesn't work?  (or has the C++ standards
committee finally decided to break all pointers just for the hell of
it?)   SWIG does this internally and has never had any problems.

> There is also
> nothing to stop the Python code from modifying the integer, causing
> the C code to dereference arbitrary memory locations. It shouldn't be
> possible for Python code to cause core dumps. You should use
> PyCObjects instead.

Just because you use a CObject doesn't mean you're going to eliminate
core dumps.  Of course, I personally believe that you should be able
to modify the pointer value if you really want to--but that's just me :-).

Cheers,

Dave