Re: Emacs crashes after customizing tabbar-default-face

[Stephen Berman]

On Sat, 14 Feb 2004 12:32:59 +0100 David Ponce <address@hidden> wrote:

> Hi Stephen,
>
>> Using David Ponce's tabbar.el, I invoked customize-face, unchecked the
>> Background attribute of tabbar-default-face and saved the
>> customization.  This resulted in a stream of messages alternating
>> between "Invalid face background" and "Invalid face foreground".  The
>> messages were not displayed in the echo area but only in the
>> *Messages* buffer.  Rapidly scrolling the *Messages* buffer while
>> these messages were being recorded caused Emacs to crash.  Rechecking
>> the Background attribute of tabbar-default-face and saving the setting
>> eliminated the messages and scrolling the *Messages* buffer no longer
>> caused Emacs to crash.  This (both the crash and the stream of
>> messages) has only happened with this particular customization;
>> unchecking the Foreground attribute, or unchecking or otherwise
>> customizing the Fore- or Background attributes of the other tabbar
>> faces, has been innocuous.
>
> There was a bug in tabbar that used a nil tab bar background face.
> I just committed a fix in the emhacks CVS repository at sourceforge.

I confirm that the invalid face messages now don't appear -- thanks
for the fix.

> However that shouldn't make Emacs crash ;-)

I don't think the nil face directly caused the crash, but led to it by
inducing the steady stream of messages, which combined with scrolling
(and perhaps other buffer actions) made Emacs crash.  This suggests a
bug in the redisplay code (the backtrace shows what look like strange
values (window=-2007082552) in xdisp.c and a redisplay_window_error in
eval.c).  

--Steve Berman