Failure building Emacs master

[Angelo Graziosi]

Trying to build master r128650.3139914f51 on MSYS2/MinGW64 fails as follows:

MINGW_INSTALLS=mingw64 makepkg-mingw -sLf
[...]
==> Avvio di prepare() in corso...
patching file src/image.c
Hunk #1 succeeded at 8206 (offset 344 lines).
patching file src/lread.c
Hunk #1 succeeded at 4418 (offset 67 lines).
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
Your system has the required tools.
Building aclocal.m4 ...
Running 'autoreconf -fi -I m4' ...
You can now run './autogen.sh git'.
==> Avvio di pkgver() in corso...
==> Versione aggiornata: mingw-w64-emacs-git r128650.3139914f51-1
==> Avvio di build() in corso...
configure: loading site script /etc/config.site
checking for xcrun... no
checking for GNU Make... make
checking build system type... x86_64-w64-mingw32
checking host system type... x86_64-w64-mingw32
checking the compiler's target... x86_64-w64-mingw32
[...]
Configured for 'x86_64-w64-mingw32'.

  Where should the build process find the source code? 
/C/msys64/tmp/mingw-w64-emacs-git/src/emacs
  What compiler should emacs be built with?               gcc 
-march=x86-64 -mtune=generic -O2 -pipe
  Should Emacs use the GNU version of malloc?             no
    (The GNU allocators don't work with this system configuration.)
  Should Emacs use a relocating allocator for buffers?    no
  Should Emacs use mmap(2) for buffer allocation?         yes
  What window system should Emacs use?                    w32
[...]
config.status: executing etc-refcards-emacsver.tex commands
configure: WARNING: This configuration installs a 'movemail' program
that retrieves POP3 email via only insecure channels.
To fix this you can use '/tmp/mingw-w64-emacs-git/src/emacs/configure 
--without-pop'.

make -C nt all
make -C lib all
make info-real info-dir
make[1]: ingresso nella directory 
"/tmp/mingw-w64-emacs-git/src/build-x86_64-w64-mingw32/nt"
make[1]: ingresso nella directory 
"/tmp/mingw-w64-emacs-git/src/build-x86_64-w64-mingw32/lib"
Makefile:60: ../nt/gnulib-cfg.mk: No such file or directory
make[1]: ***  Nessuna regola per generare l'obiettivo 
"../nt/gnulib-cfg.mk".  Arresto.
make[1]: uscita dalla directory 
"/tmp/mingw-w64-emacs-git/src/build-x86_64-w64-mingw32/lib"
make: *** [Makefile:403: lib] Error 2
make: *** Attesa per i processi non terminati....
  RC       emacs.res
  CCLD     addpm.exe
make[1]: ingresso nella directory 
"/tmp/mingw-w64-emacs-git/src/build-x86_64-w64-mingw32"
make -C doc/lispref info
make[2]: ingresso nella directory 
"/tmp/mingw-w64-emacs-git/src/build-x86_64-w64-mingw32/doc/lispref"
/usr/bin/mkdir -p 
/C/msys64/tmp/mingw-w64-emacs-git/src/emacs/doc/lispref/../../info
  GEN 
/C/msys64/tmp/mingw-w64-emacs-git/src/emacs/doc/lispref/../../info/elisp.info
  CCLD     cmdproxy.exe
[...]

Beside this, I don't understand this warning:

configure: WARNING: This configuration installs a 'movemail' program
that retrieves POP3 email via only insecure channels.
To fix this you can use '/tmp/mingw-w64-emacs-git/src/emacs/configure 
--without-pop'.

You should have a configure with enable by default. If one wants POP 
then it will configure --with-pop..

Angelo