[MLton-user] MLton on a new mac

[Matthew Fluet]

On Sat, Feb 12, 2011 at 11:45 AM, Sean McLaughlin <seanmcl at gmail.com> wrote:
> 1) I installed gmp via MacPorts
> 2) Downloaded MLton, statically linked
> (http://mlton.org/pages/Download/attachments/mlton-20100608-1.x86-darwin.gmp-static.tgz)

That is a binary package of 32-bit executables that generate 32-bit
executables.  Although MacOSX supports both 32-bit and 64-bit
executables, the development tools in versions prior to Snow Leopard
defaulted to generating 32-bit executables.  With Snow Leopard,
development tools default to generating 64-bit executables.
MacPorts has followed suit, so the GMP library built by MacPorts on
Leopard or earlier is a 32-bit library, while the GMP library built by
MacPorts on Snow Leopard is a 64-bit library.  As noted in the
followup, it is possible to ask MacPorts to build both 32-bit and
64-bit versions of the GMP library into one universal library.

http://mlton.org/pages/Download/attachments/mlton-20100608-1.amd64-darwin.gmp-static.tgz
is a binary package of 64-bit executables that generate 64-bit
executables.  If you had installed that package, then you should have
had no trouble with the 64-bit version of the GMP library.