A list of bugs

[Lars Hansen]

Hi

I have collected a few bugs, described below.


expand-file-name crashes Emacs
------------------------------
Calling expand-file-name with default-directory set to nil, such as in

   (let ((default-directory nil))
      (expand-file-name "foo"))

makes Emacs crash without a word. I experience the problem with
Emacs 21.2 and 20.7 under MS Windows.


Microsoft Windows cannot shut down Emacs
----------------------------------------
Start Emacs (21.2 or 20.7) under MS Windows and try to close MS Windows.
Then you get an error message saying that MS Windows cannot shut down
Emacs. I suspect that Emacs does not handle the WM_QUERYENDSESSION (0x0011)
sent to applications by MS Windows to make them do things like ask the user
if unsaved files should be saved. I have not checked whether my suspicion
holds.


Font lock in multi line text strings
------------------------------------
Font lock in emacs-lisp-mode gets very confused when a multi line text string
(such as a doc string) have a line starting with 'with' or '(' (no quotes).


Redraw of MS Windows title bar
------------------------------
When running under MS Windows, the title bar of Emacs frames often flicker.
I seems they are redrawn unnecessarily. This problem is introduced with Emacs 
21,
it is not there with Emacs 20.


Scroll/timer bug
----------------
I have reported this bug before -- however at that time I suspected the error
to be MS Windows specific. Now I have seen it on a Linux system as well.

When I scroll a window by holding down the the down-arrow button,
the scrolling motion have anoying jumps now and then. What happes
is, obviously, that the window gets recentered.

I suspect this problem has to do with timers.
It can be reproduce with Emacs 20 or 21 under MS Windows using a .emacs file
with the following lines:

   (setq display-time-interval 1)
   (display-time-mode t)
   (setq scroll-margin 1)
   (setq scroll-conservatively 1000)

Start Emacs and visit any relatively large file. Hold the down-arrow button
down. The window will the scroll upwards, and most of the time the point
stays, as i should, one row from the bottom of the window. But occasionally
it will go down to the bottom of the screen. If you have a fast keyboard
repeat rate you will see that the problem comes when the clock on the
mode line is updated. Not necessarily each second, but sometimes a few
seconds in a row. It probably depends on when keyboard events occur
related to the timer events. You can also reproduce the problem without
using automatic keyboard repeating, just by pressing the down-arrow about
say 50-100 times, waiting for the correct timing to occur. If you then stop,
when the problem comes, point stays at the bottom of the window.

I have the problem on a Suse Linux system as well -- here the problem comes
from something in the site file, but I don't know exactly what.


Lars Hansen
e-mail: larsh@math.ku.dk