64-bit Python?

Bjorn Pettersen BPettersen at NAREX.com
Thu Jun 6 15:52:17 EDT 2002


> From: Kragen Sitaker [mailto:kragen at pobox.com] 
> 
> loewis at informatik.hu-berlin.de (Martin v. Löwis) writes:
> > I believe there is another limit: the maximum length of a string, 
> > list, or tuple is 2**31-1 on 64-bit platforms where a C int is 4 
> > bytes. That, in particular, includes mmapped objects as well.
> 
> Yes, this is correct.  Even the buffer interface, which my 
> arrayfrombuffer package[0] uses to provide access to mmapped 
> files as Numeric arrays inexplicably uses int instead of size_t.
> 
> The problem is that all of the 64-bit platforms I have access 
> to (various Linuxes on Alpha and IA-64, Tru64 on Alpha) have 
> 4-byte ints and 8-byte longs, at least by default.  This is 
> called "LP64": longs and pointers are 64, but ints are 32, so 
> all the code that assumes ints are 32 will continue to work.

Are you using Win64 on IA-64? Last time I checked (using the MS compiler) a long was still 32 bits, and you had to use __int64 to get a 64 bit integer...

-- bjorn





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