[vtk-developers] Guidance needed fixing problems doing 64bit compile on Mac OS X

[Sean McBride]

On 2006-10-26 12:40, David Gobbi said:

>A "long" would do the trick, I believe that the C standard requires it 
>to be as big as a pointer, and this would cause an absolute minimum of 
>backwards-compatibility issues.

Actually C only requires long to be at least as big as int.  In fact, if
you look at the table on this page:

<http://developer.apple.com/macosx/64bit.html>

We see that in the real world(TM) long is not always 64 bit, even on 64 bit
systems.

The type 'ptrdiff_t' is a special type (like size_t) who's exact purpose
is to be an integer type big enough to hold pointers.

There may possibly be some crappy compilers out there that don't support
ptrdiff_t, but I would be surprised.

-- 
____________________________________________________________
Sean McBride, B. Eng                 sean at rogue-research.com
Rogue Research                        www.rogue-research.com 
Mac Software Developer              Montréal, Québec, Canada