Hi,
On this page, http://www.mono-project.com/Supported%5FPlatforms, 64bit windows isn't listed as a supported platform. However, I keep getting the feeling that it's supported (the x64 codegenerator works...). Can anyone conclusively confirm this theory?
Thanks
"Supported" doesn't necessarily mean it works, and "not supported" does not necessarily mean it doesn't work. Instead, when folks who write software say they support a platform, it means that they have tested the software on that platform and will accept bug reports related to failure to work on that platform.
Using the software on platforms that are "not supported" means you're using them at your own risk. (Of course, free software is generally always used at your own risk.)
For the specific case of 64-bit Windows, I would expect Mono to work in 32-bit mode, but I haven't investigated. It's not just a matter of having an x64 code generator; the ABI for 64-bit Linux differs from 64-bit Windows, the exception handling mechanisms are different, etc.
The fact that there exists an x64 code generator that works under Linux doesn't mean that the same code generator would work under Windows. The operating system use different ABI, ie. calling conventions and other related things. See Old New Thing for details.
As far as I know there is no native Mono port to Win64, but the Win32 one works fine under WOW even on x64 systems.
The Mono project does not provide binaries/installers for Win64, because it is not officially supported. As the other answers indicate, the Win32 version works perfectly fine under 64bit versions of Windows.
However, Win64 support has been contributed and tested by some really great contributors who use it for their commercial product.
You can build it yourself from Mono's SVN using "mono.sln" in /mono/msvc.
Use the "Debug_eglib|x64" or "Release_eglib|x64" configurations.