bug#24525: autogen.sh fails in mingw64

[Eli Zaretskii]

> From: Vincent Semeria <vincent.semeria@gmail.com>
> Date: Sat, 24 Sep 2016 14:10:50 +0200
> 
> I try to build branch emacs-25 (commit 
> f2819241bc93b641f13e1a04f3520fadb8ed53a8) on Windows 10.
> Following the instructions of file nt/INSTALL.W64, autogen.sh gives me :
> 
> INCONNU@DESKTOP-RU9MU9H MINGW64 /c/emacs-git
> $ ./autogen.sh
> Checking whether you have the necessary tools...
> (Read INSTALL.REPO for more details on building Emacs)
> Checking for autoconf (need at least version 2.65)...
> ok
> Checking for automake (need at least version 1.11)...
> ok
> Your system has the required tools.
> Running 'autoreconf -fi -I m4' ...
> ' is already registered with AC_CONFIG_FILES.
> ../../lib/autoconf/status.m4:288: AC_CONFIG_FILES is expanded from...
> configure.ac:5374: the top level
> autom4te: /usr/bin/m4 failed with exit status: 1
> aclocal-1.15: error: echo failed with exit status: 1
> autoreconf: aclocal failed with exit status: 1

Is it possible that you are being hit by this issue, mentioned in
INSTALL.W64:

  The autocrlf feature of Git may interfere with the configure file, so it is
  best to disable this feature by running the command:

    git config core.autocrlf false