Let me first say that I still stand by my previous comments that PostgreSQL is in much less need of a native 64-bit version on Windows than other databases - and less than PostgreSQL on other platforms. (Both this and the previous post talk about server-side support, having support client-side in libpq and ODBC is obviously important)
That said, I am now happy to say that with the effort of several people, it looks like we now have basic 64-bit support for PostgreSQL on Windows. During the past couple of weeks I have cleaned up and extended the patch from Tsutomu Yamada, which in itself builds on the work of several others, and applied it to cvs. As of today, you can build and run PostgreSQL on 64-bit Windows from the official repository.
This is obviously just the beginning. Unfortunately, Windows in general seems to be lagging behind quite severely on the 64-bit front, and this appears to be particularly true of the open source libraries. I've so far been unable to find 64-bit builds of many of the libraries we rely on for full functionality (gettext, zlib, libxml, libxslt, libiconv, tcl, uuid). While in theory support for these things should show up as soon as they are available, that's obviously not tested. If you know where I can download complete 64-bit binaries (including .lib and .h files for development) of any of these projects, please let me know.
Also, this is not very well tested yet. It passes all the PostgreSQL regression tests. That's pretty much all the tests I've been running on it. This is obviously a point where a lot of people can help - so please do. I have made a set of pre-alpha binaries available here. This is a bare-bones build of cvs head earlier today - things like OpenSSL that do have 64-bit binaries available is also disabled. It comes with no installer - just unzip into a directory, and use the initdb and pg_ctl commands directly. So if you have a 64-bit environment, please download and test this against your application!
All 2360 tests in my rails application passed against this alpha.
It works for simple stuff at least.
Great, thanks for testing!
If you check out the free versions of Oracle Express there are no 84-bit versions as well...
I ran my application test suite against this build as well. I ran into (and fixed) a few 8.5 issues, but nothing unexpected. It seems to work well.