bug#25221: Packages manager not working in WSL emacs-25 build

[Angelo Graziosi <angelo.graziosi@alice.it>]

I recently enabled and installed WSL (Windows Subsystem for Linux) in 
Windows 10 [1] and so tried to build Emacs.

Building Emacs master hangs [2]. So tried emacs-25 branch (+release and 
testing). This branch builds if one adopts the work around suggested in 
/et/PROBLEMS and from the WEB [3]:

echo 0 | sudo tee /proc/sys/kernel/randomize_va_space
./autogen.sh
./configure --prefix=/opt/emacs --without-x
make...

It also seems to work but trying to install packages from MELPA/ELPA fails.

More precisely, in emacs25:

M-x package-list-packages

After the "Package refresh done" I cannot type anything nor I can quit 
(C-x C-c). If I do, for example pressing the down arrow key, in the 
packages buffer I see something like this

[...]
[1]+  Stopped                 emacs25ailable  melpa      No description 
available...
angelo@MYPC~   20151026.1233 available  melpa      play 2048 in Emacs..
$ 4clojure           20131014.1507 available  melpa..
[...]

At this point I can only try to kill Emacs. It is as if Emacs were 
reduced to background (C-z), and a 'fg' seems to resurrect it but is 
unusable (I have to close the WSL bash window).

Now, at the moment, enabling and installing WSL installs Ubuntu 14.04 
and one can install other Ubuntu packages with apt-get. So I installed 
the emacs24-nox packages which works without this Packages manager issue!

Then for sanity check I did a build of emacs-24.3.tar.gz (the same 
version offered by WSL-Ubuntu) and it works as expected (also the 
packages Manager).

So the issue seems to regards only emacs-25 branch.


Ciao,
  Angelo.


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[1] https://msdn.microsoft.com/it-it/commandline/wsl/install_guide
     https://msdn.microsoft.com/it-it/commandline/wsl/faq

[2] http://lists.gnu.org/archive/html/emacs-devel/2016-12/msg00427.html

[3] 
http://stackoverflow.com/questions/38905344/windows-bash-emacs-build-fail-memory-protection-enabled