bug#17386: 24.3.90; emacs_abort in cmcheckmagic

[Nicolas Richard <theonewiththeevillook@yahoo.fr>]

It happened again (at least it looks very very similar to me) but I'm
afraid I'm not bringing much new information.

Anyway, just to show that it is the same problem :

(gdb) f 2
#2  0x0812f9b7 in cmcheckmagic (tty=0x897de50) at cm.c:120
120             emacs_abort ();
(gdb) l
115     cmcheckmagic (struct tty_display_info *tty)
116     {
117       if (curX (tty) == FrameCols (tty))
118         {
119           if (!MagicWrap (tty) || curY (tty) >= FrameRows (tty) - 1)
120             emacs_abort ();
121           if (tty->termscript)
122             putc ('\r', tty->termscript);
123           putc ('\r', tty->output);
124           if (tty->termscript)
(gdb) p curY(tty)
$1 = 41
(gdb) p FrameRows(tty)
$2 = 23

The situation was as follows: I had a detached tmux session with an
"emacs -nw" in it (in gdb), and I had a graphical frame open also (via
emacsclient). I then tried to reattach to the tmux session, and that's
when emacs crashed.

I guess it would help to know what happens when tmux is detached.
Perhaps emacs should receive some kind of notification, and that doesn't
happen in some cases ? Next time I have to close emacs I'll try using
screen instead of tmux.

-- 
Nico.