bug#19989: 25.0.50; Build instructions on Windows

[Eli Zaretskii <eliz@gnu.org>]

> Date: Fri, 6 Mar 2015 17:44:04 -0800
> From: Ilya Zakharevich <ilya@math.berkeley.edu>
> Cc: rudalics@gmx.at, 19989@debbugs.gnu.org
> 
> On Fri, Mar 06, 2015 at 01:16:36PM +0200, Eli Zaretskii wrote:
> > > Date: Fri, 6 Mar 2015 01:59:52 -0800
> > > From: Ilya Zakharevich <ilya@math.berkeley.edu>
> > > Cc: Eli Zaretskii <eliz@gnu.org>, 19989@debbugs.gnu.org
> > > 
> > >   A) apparently, the download and build instructions changes not so
> > >      long ago, so what google finds are obsolete irrelevant
> > >      instructions.
> > 
> > The build instructions changed in May 2013, almost 2 years ago.
> 
> Irrelevant.

Relevant.  You should look at the date of the instructions you get
from Google before you consider them valid.

> Google brings (many variants) of wrong instructions about
>   • what to download
>   • how to build it
>  — and no correct instructions (at least close to the top of the list;
> my google shows 80 hits, and it did not help much).

Which might mean that everybody else succeeded in building Emacs just
by following nt/INSTALL.

> If you download an obsolete version, you get obsolete instructions
> (coming with this version).  So it is hard to detect that what you get
> is bogus.

The first place to look is in the package, not in Google hits.  Follow
that rule, and you will be generally fine, not only with Emacs.

> > > The warning which nt/configure.bat gives is not specific enough (at
> > > least when shown on background of all the [wrong] info found by googling):
> > 
> > If no one complains about something major for the MinGW/MSYS build
> > when Emacs 24.5 is released, nt/configure.bat will be deleted from the
> > repository, so it won't be able to confuse anyone anymore.
> 
> In view of the results of googling, I would prefer if this file were
> kept, but would produce a message like
> 
>      Build via nt/configure.bat is replaced by a build via:
>        installing MSYS, MINGW, and running the top-level configure.
>      See nt/INSTALL for details.

Leaving the file for that purpose makes no sense.  If someone is
looking for it because it was mentioned in some Google hit, they will
know the hit was outdated.