RE: [xml] python bindings initialization

[Stéphane Bidoul <stephane bidoul softwareag com>]

  Yes this sounds like an interesting solution, but ... it
> break in my regression tests. Basically I compile with 
> --with-mem-debug
> enabled, i.e. all the memory is allocated, from the start, with
> the memory debugging shell. Your trick seems to confuse something
> somewhere, and all regression tests with python now fail with:
>   paphio:~/XML/python/tests -> ./build.py
>   Memory leak -422 bytes
>
> I.e. we end-up with a shifted memory count, there is 2 ways to 
> solve this:
>   - the unclean way: never report negative memory allocated memory
>     and reset the base when it happens
>   - find out about where that base shift comes from (probably the
>     memory allocated with the debug memory routines when running 
>     with memory debug - can probably be tested by checking the 
>     existing memory routine before switching to debug) and account
>     for it when reporting.
>
> I think your trick solves the hardest part for users, but it would be
> great if the problem for running the regressions tests in debug mode
> could be solved. BTW there is also a serious problem with the 
> debug mode
> when running the libxslt python regression tests, the whole set 
> (debug + libxml2 + libxslt + python) seems to completely confuse the
> memory allocator (I assume it's something similar to the problem you
> fixed), but it still happen with your patch in.
>
> I probably won't be able to make the release before this week-end, 
> could you have a look at those cornercases if you have time ?

Hm. I can't reproduce on windows. Any idea?
I put a breakpoint in xmlMemMalloc, and the first call
comes from xmlInitCharEncodingHandlers. But that is cleaned-up
nicely by the xmlCleanupParser, no no leak nor positive, nor negative.
Maybe I missed a #define: Igor's configures sets DEBUG_MEMORY_ALLOCATION,
is that correct? (I'd say yes having looked at globals.c, but...).

-sbi