[MLton] 64-bit support

[Matthew Fluet]

> MLton does not seem to currently have support for building native
> 64-bit executables.  In our projects we need to build 64-bit programs.
> This is mostly because only 64-bit versions of certain system
> libraries we use are available.
>
> Are there any plans to add 64-bit support?

Yes, work is underway.  There is a summary of the current progress at:
   http://mlton.org/pipermail/mlton/2005-December/028421.html
The C-side of the Basis Library implementation has been refactored to 
properly handle different native representations of primitive C-types; The 
SML-side of the Basis Library is currently being refactored.