[Python-Dev] Invalid memory read in PyObject_Free

[Guido van Rossum]

> >> In obmalloc.c there is some code that does not strictly conform to
> >> ANSI C.
> >
> > True.  If we wanted to strictly conform to ANSI C, we couldn't do many
> > things we do.
> 
> Sure, but this one is a little bit more eccentric than the others...

Hm...  Do you have a suggestion for making the code more ANSI
conformant?  Surely checking whether an address is within a certain
range shouldn't require accessing any out-of-bounds memory?  Or am I
mistaken about how the offending piece of code works?

> > I haven't heard of platforms where turning off pymalloc is required --
> > unless we hear about those, I expect that for 2.4, pymalloc may no
> > longer be optional.  (The reason: maintaining two versions of the same
> > code is a pain, and usually the version that's not selected by default
> > is severely broken after a few releases.)
> 
> Is this a real problem with pymalloc?
> 
> #ifndef PYMALLOC
> #define PyObject_Alloc malloc
> #else
> ...
> #endif
> 
> isn't likely to bitrot that fast.  But, whatever, it's no big deal to
> me.

If that's all, it probably isn't a big deal. :-)

[Doing anything to avoid having to look at the actual code...]

--Guido van Rossum (home page: http://www.python.org/~guido/)