bug#19989: 25.0.50; Build instructions on Windows

[Eli Zaretskii]

> Date: Fri, 6 Mar 2015 17:47:21 -0800
> From: Ilya Zakharevich <ilya@math.berkeley.edu>
> Cc: Eli Zaretskii <eliz@gnu.org>, martin rudalics <rudalics@gmx.at>,
>  19989@debbugs.gnu.org
> 
> On Fri, Mar 06, 2015 at 03:14:29PM +0100, Óscar Fuentes wrote:
> > Another option is to recommend MSYS2 for those interested on building
> > Emacs on Windows. It is a straightforward process.
> 
> Is there any technical reason for not going the way of
>   CC=i686-pc-mingw32-gcc
>   LINK=i686-pc-mingw32-gcc
>   ./configure
>   make
> in cygwin’s bash?

I don't think anyone tried that.

One problem you might bump into is that building Emacs requires to
actually run Emacs you've built, and also lib-src/make-docfile, which
are not Cygwin programs.  If the Cygwin shell invokes them with
Cygwin-style absolute file names, these programs might fail, claiming
that files don't exist.  That's exactly the problem that MSYS attempts
to solve; it is otherwise just a fork of Cygwin.