bug#27804: 26.0.50; Emacs backgrounds itself during package-list-packages on WSL

[Josh Howard]

This bug report will be sent to the Bug-GNU-Emacs mailing list
and the GNU bug tracker at debbugs.gnu.org.  Please check that
the From: line contains a valid email address.  After a delay of up
to one day, you should receive an acknowledgment at that address.

Please write in English if possible, as the Emacs maintainers
usually do not have translators for other languages.

Please describe exactly what actions triggered the bug, and
the precise symptoms of the bug.  If you can, give a recipe
starting from 'emacs -Q':

When running Emacs in "Bash on Ubuntu on Windows" (WSL) and executing M-x 
package-list-packages, you will get the typical list of packages. Hitting a 
movement key (C-n, down arrow, etc.) will cause Emacs to background (STOP) 
itself. You can 'fg' the process, but it's in essentially a useless state at 
that point. This is consistent whether running with '-Q' or not.

If Emacs crashed, and you have the Emacs process in the gdb debugger,
please include the output from the following gdb commands:
    'bt full' and 'xbacktrace'.
For information about debugging Emacs, please read the file
/usr/share/emacs/26.0.50/etc/DEBUG.

In GNU Emacs 26.0.50 (build 1, x86_64-pc-linux-gnu)
 of 2017-07-23 built on lgw01-10
System Description:     Ubuntu 16.04.2 LTS

Recent messages:
Loading ede...done
Loading paren...done
For information about GNU Emacs and the GNU system, type <f1> C-a.
Quit
Making completion list...

Configured using:
 'configure --build=x86_64-linux-gnu --prefix=/usr
 '--includedir=${prefix}/include' '--mandir=${prefix}/share/man'
 '--infodir=${prefix}/share/info' --sysconfdir=/etc --localstatedir=/var
 --disable-silent-rules '--libdir=${prefix}/lib/x86_64-linux-gnu'
 '--libexecdir=${prefix}/lib/x86_64-linux-gnu' --disable-maintainer-mode
 --disable-dependency-tracking --prefix=/usr --sharedstatedir=/var/lib
 --program-suffix=-snapshot --with-modules=yes --with-x=no 'CFLAGS=-g
 -O2 -fstack-protector-strong -Wformat -Werror=format-security'
 'CPPFLAGS=-Wdate-time -D_FORTIFY_SOURCE=2'
 'LDFLAGS=-Wl,-Bsymbolic-functions -Wl,-z,relro''

Configured features:
JPEG SOUND GPM DBUS NOTIFY LIBSELINUX GNUTLS LIBXML2 ZLIB MODULES
LIBSYSTEMD

Important settings:
  value of $LANG: en_US.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Lisp Interaction

Minor modes in effect:
  tooltip-mode: t
  global-eldoc-mode: t
  eldoc-mode: t
  electric-indent-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message subr-x puny seq byte-opt gv
bytecomp byte-compile cconv cl-loaddefs cl-lib dired dired-loaddefs
format-spec rfc822 mml easymenu mml-sec password-cache epa derived epg
epg-config gnus-util rmail tool-bar rmail-loaddefs mm-decode mm-bodies
mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader sendmail
regexp-opt rfc2047 rfc2045 ietf-drums mm-util mail-prsvr mail-utils
term/xterm xterm time-date mule-util tooltip eldoc electric uniquify
ediff-hook vc-hooks lisp-float-type tabulated-list replace newcomment
text-mode elisp-mode lisp-mode prog-mode register page menu-bar
rfn-eshadow isearch timer select mouse jit-lock font-lock syntax
facemenu font-core term/tty-colors frame cl-generic cham georgian
utf-8-lang misc-lang vietnamese tibetan thai tai-viet lao korean
japanese eucjp-ms cp51932 hebrew greek romanian slovak czech european
ethiopic indian cyrillic chinese composite charscript charprop
case-table epa-hook jka-cmpr-hook help simple abbrev obarray minibuffer
cl-preloaded nadvice loaddefs button faces cus-face macroexp files
text-properties overlay sha1 md5 base64 format env code-pages mule
custom widget hashtable-print-readable backquote dbusbind inotify
multi-tty make-network-process emacs)

Memory information:
((conses 16 95541 6693)
 (symbols 48 19302 1)
 (miscs 40 34 96)
 (strings 32 27954 1217)
 (string-bytes 1 748177)
 (vectors 16 12542)
 (vector-slots 8 440353 5396)
 (floats 8 49 572)
 (intervals 56 230 0)
 (buffers 992 12)
 (heap 1024 34128 1561))