bug#28279: 25.2; repeatable crash when hitting C-g twice

[Eric Hoffman]

I dont think its necessary, bu after 30 years I've developed the muscle
memory of hitting C-g twiceif I want to get back to a known state.
I've noticed this happening on OSX using a brew-installed 25.4, but
recently after noticing it on Freebsd, I compiled from source with
deubugging turned on. It doesn't happen every time, but usually about
once every 30 minutes with my particular usage

  OS: FreeBSD 11.0-RELEASE-p9
  Compiler: FreeBSD clang version 3.8.0 (tags/RELEASE_380/final 262564)
           (based on LLVM 3.8.0)
  Emacs: "25.2.1"
  Stacktrace:
  0x4af3e4 <emacs_backtrace+0x54> at  /usr/home/yuri/emacs-25.2/src/emacs-25.2.1
  0x4938fc <terminate_due_to_signal+0x5c> at  
/usr/home/yuri/emacs-25.2/src/emacs-25.2.1
  0x4ad7a3 <emacs_abort+0x13> at  /usr/home/yuri/emacs-25.2/src/emacs-25.2.1
  0x50c474 <Fsignal+0x4b4> at /usr/home/yuri/emacs-25.2/src/emacs-25.2.1
  0x512cf5 <Fassq+0x15> at /usr/home/yuri/emacs-25.2/src/emacs-25.2.1
  0x48cfbe <Fterminal_parameter+0x7e> at  
/usr/home/yuri/emacs-25.2/src/emacs-25.2.1
  0x48c1e7 <tty_send_additional_strings+0x17> at  
/usr/home/yuri/emacs-25.2/src/emacs-25.2.1
  0x48b7ef <tty_reset_terminal_modes+0x1f> at  
/usr/home/yuri/emacs-25.2/src/emacs-25.2.1
  0x4ae851 <reset_sys_modes+0x101> at  
/usr/home/yuri/emacs-25.2/src/emacs-25.2.1
  0x4ae738 <reset_all_sys_modes+0x18> at  
/usr/home/yuri/emacs-25.2/src/emacs-25.2.1
  0x49dce5 <handle_interrupt+0xb5> at  
/usr/home/yuri/emacs-25.2/src/emacs-25.2.1
  0x4aecd7 <deliver_process_signal+0x37> at  
/usr/home/yuri/emacs-25.2/src/emacs-25.2.1
  0x80195378f <pthread_sigmask+0x4ff> at /lib/libthr.so.3
  0x801952d6f <pthread_getspecific+0xe9f> at /lib/libthr.so.3

If someone wants to track this down and wants more information, I can
try to run it in the debugger (i struggle some with lldb), or recompile
with instrumentation

as always, thanks for...emacs...I think the last time I filed a bug was
around 1990



In GNU Emacs 25.2.1 (x86_64-unknown-freebsd11.0)
 of 2017-08-23 built on zeitgeist.tenuki.org
Configured features:
SOUND NOTIFY ACL GNUTLS LIBXML2 ZLIB

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

Major mode: Fundamental

Minor modes in effect:
  display-time-mode: t
  shell-dirtrack-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  electric-indent-mode: t
  file-name-shadow-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  buffer-read-only: t
  line-number-mode: t
  transient-mark-mode: t

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.
Quit [2 times]

Load-path shadows:
None found.

Features:
(shadow sort mail-extr emacsbug message dired format-spec rfc822 mml
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mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader sendmail
rfc2047 rfc2045 ietf-drums mm-util help-fns help-mode easymenu
cl-loaddefs pcase cl-lib mail-prsvr mail-utils time-date time image
shell pcomplete comint regexp-opt ansi-color ring mule-util tooltip
eldoc electric uniquify ediff-hook vc-hooks lisp-float-type
tabulated-list newcomment elisp-mode lisp-mode prog-mode register page
menu-bar rfn-eshadow timer select mouse jit-lock font-lock syntax
facemenu font-core 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 charscript case-table epa-hook jka-cmpr-hook help simple abbrev
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 kqueue multi-tty
make-network-process emacs)

Memory information:
((conses 16 87371 5095)
 (symbols 48 19375 0)
 (miscs 40 113 98)
 (strings 32 15961 5305)
 (string-bytes 1 467507)
 (vectors 16 10054)
 (vector-slots 8 385356 12608)
 (floats 8 155 132)
 (intervals 56 127 3)
 (buffers 976 24))