[Python-Dev] Removing tp_compare?

[Guido van Rossum]

On Sun, Feb 1, 2009 at 4:22 AM, Mark Dickinson <dickinsm at gmail.com> wrote:
> On Sat, Jan 31, 2009 at 9:28 PM, "Martin v. Löwis" <martin at v.loewis.de> wrote:
>
>> tp_reserved sounds fine. In 3.0.1, filling it with a function pointer
>> should give no error, since that would be a binary-incompatible change.
>
> I'm not sure I understand you here.  Are you saying that in your
> opinion it is safe to change the type of tp_reserved
> from (cmpfunc *) to some other (dummy) function pointer?

Sounds like Martin is referring to your suggestion to raise an
exception when initializing a type that has a non-NULL thing here. I
agree with him.

> I now realize (thanks to your message) that changing the type
> to (void *) isn't entirely safe, since sizeof(void*) may be
> different from sizeof(cmpfunc*) on some platforms.

I don't think it matters on any platforms we care about.

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