Re: determining 32 v. 64 bit compilatio

[Bob Friesenhahn]

On Tue, 29 Jun 2010, Russ Allbery wrote:
> I suspect that you're dealing with "all the world is Linux" code, and
> therefore doing something like:
>
> AC_CHECK_SIZEOF([long])
> AS_IF([test "$ac_cv_sizeof_long" -eq 8],
>    [AC_DEFINE([OSBIT], 64, [Define to the size of a long in bits.])],
>    [AC_DEFINE([OSBIT], 32, [Define to the size of a long in bits.])])
>
> would do what you want, but you won't find something exactly like that
> built into Autoconf since it's not generally a meaningful thing to do on a
> broader variety of platforms.

More specifically, this test would not be very useful for Microsoft 
Windows where the 'long' type is 32-bit in a 64-bit application.

There are also OSs which support various optional application models 
with various sizes for 'long' and pointers.

Bob
--
Bob Friesenhahn
address@hidden, http://www.simplesystems.org/users/bfriesen/
GraphicsMagick Maintainer,    http://www.GraphicsMagick.org/