RFC: Cygwin 64 bit?

Yaakov (Cygwin/X) yselkowitz@users.sourceforge.net
Wed Jun 29 05:51:00 GMT 2011

On Wed, 2011-06-29 at 06:29 +0100, Andy Koppe wrote:
> 1.7 was a complete distro from early on, due to binary backward
> compatibility and the unionfs with 1.5. A parallel 1.5 wasn't needed
> to run 1.5 stuff, only to build it.

FWIW I rebuilt all my packages for 1.7, that's why I use that as a
reference point.

> This wouldn't be the case with a pure 64-bit Cygwin. As soon as you
> needed any tool not yet available in 64-bit, you'd need to switch back
> to 32-bit. Trying to mix them by sticking both in the path isn't gonna
> work well, due to the same DLLs appearing in both distros' /bin
> directories, so the wrong one is bound to be picked up somewhere.
> (Incidentally, the /bin vs /bin64 scheme would have the same problem.)
> Even if that did work, the separate root directories would make for a
> very "interesting" user experience.

The parallel installation setup isn't meant to be a "[end-]user
experience" , its meant to allow maintainers to have a functioning
32-bit distro while working to create a 64-bit one.  Nowadays I do just
about everything from Ports' GNOME desktop, and I'll still need to do
all those things while we work on building up the 64-bit platform.

Here's what I have in mind:

1) We port w32api/newlib/Cygwin and GCC to x86_64-pc-cygwin;
2) Build a x86_64-pc-cygwin cross-binutils (done?) and cross-gcc;
3) Cross-compile the basic x86_64 development platform;
4) Build the x86_64 distro natively from the bottom up.

Once (4) is well under way, then end-users can start testing and using
the x64 distro, and switch over once the packages they want are


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