Re: GDB cannot access memory after Emacs abort

Stephen Berman
2007-11-13T22:36:28Z

On Mon, 12 Nov 2007 10:38:36 +0300 Vladimir Prus <ghost@cs.msu.su> wrote:

> Daniel Jacobowitz wrote:
>
>> On Sat, Nov 10, 2007 at 10:38:14PM -0800, Michael Snyder wrote:
>>>
>>> Making sure that I understand -- you ran emacs under gdb,
>>> you set a breakpoint at abort, you hit the breakpoint --
>>> and your desktop is locked up?
>>>
>>> That seems unusual -- do you have any idea of the cause?
>>
>> This is pretty common when debugging X programs, IIRC. I believe
>> there's some ways in which an application can "own" a display while
>> something is in progress.
>
> I believe it's XGrabPointer, which causes all mouse and/or keyboard
> event to be delivered to specific application. If that application is
> stopped by gdb, it means, in effect, that events are not processed at all.
>
> I have no idea if that's the cause, since the emacs diff posted in another
> email does not have any apparent locking thing, but it very likely.

But as I pointed out in my followup to Jim Blandy, the lockup only
happens when emacs aborts while running under gdb; starting emacs
directly from the shell and inducing the abort does not lock up the
desktop.

Steve Berman