[Bug: 21.4.20] Killing a large number of characters in shell mode hangs xemacs

[Aidan Kehoe]

 Ar an triú lá de mí Lúnasa, scríobh lkashley at rockwellcollins.com: 

 > When deleting a large number (200,000 ish) of characters from a shell
 > window Xemacs hangs. I am using shell-mode in xemacs-base 2.10. I've
 > not experienced this problem with prior versions of xemacs/lisp.
 > 
 > Set mark at end of buffer. Move to top of buffer. Ctrl-W.
 > 
 > prstat shows Xemacs running 23% cpu. It (the xemacs) has been hung for
 > quite some time.
 > 
 >    PID USERNAME  SIZE   RSS STATE  PRI NICE      TIME  CPU PROCESS/NLWP
 >   6910 lkashley 2063M 2052M cpu1    40    0   0:18.38  23% 
 > xemacs-21.4.20/1
 > 
 > Any thoughts on how to tackle this would be appreciated.

Attach to the process with gdb, then type bt to get an idea what the C code
is doing. It sounds like the interaction with X11 is going wrong; there was
a previous problem with incremental selection transfer which would provoke a
hang like this, but that should have been fixed in 21.4.20. Maybe it
uncovered another bug. 

-- 
On the quay of the little Black Sea port, where the rescued pair came once
more into contact with civilization, Dobrinton was bitten by a dog which was
assumed to be mad, though it may only have been indiscriminating. (Saki)