[Cmake] large file support

[Brad King]

On Thu, 9 Oct 2003, Peng Liwei wrote:

> What I want is this:
>
> some computer platforms support 64-bit files,
> some only support 32-bit. To make our program
> portable, we would like CMake automatically
> detect, when I run 'ccmake', whether the platform
> support 64 or not.
> If it supports 64-bit file , then add certain compiler
> flag.

CMake supports TRY_COMPILE and TRY_RUN just like autoconf.  We have no
predefined test included with CMake for this feature.  If you know how
autoconf tests for this support, you can do the same test with CMake.

-Brad