bug#19989: 25.0.50; Build instructions on Windows

[Eli Zaretskii]

> Date: Fri, 06 Mar 2015 10:29:12 +0200
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 19989@debbugs.gnu.org
> 
> > Of course they do.  configure did not work (since the gcc found on
> > path was not MINGW one).
> 
> So that's the problem: you installed the MSYS GCC (and probably the
> whole MSYS development environment), something one shouldn't do for
> building MinGW programs.

Or maybe I again misunderstood, and the GCC found first on PATH was
the Cygwin GCC?  Then that'd be the "don't mix Cygwin with MinGW in
the same session" part of my advice again.