bug#18722: Correction

[Eli Zaretskii <eliz@gnu.org>]

> From: Titus von der Malsburg <malsburg@posteo.de>
> Cc: rudalics@gmx.at, 18722@debbugs.gnu.org
> Date: Thu, 16 Oct 2014 08:10:37 -0700
> 
> I can enter text and save the buffer before clicking menu items.  When I
> inspect the content of the file with another editor, I see that it
> contains the text that I entered before saving.

Do you see the changes in the file before or after you click on the
Emacs frame?  If before, then indeed it sounds like Emacs is reacting
to your inputs, but the display is not refreshed.

But a situation where Emacs acts on your input, but does not update
the display is inconceivable, unless some external factor is at work.
That's because the same loop where Emacs reads input also calls
redisplay, and since saving a buffer displays a message in the echo
area, calling redisplay must have updated at least the echo area.  I
cannot understand how could Emacs save a buffer, but not display the
echo area message that is part of saving that buffer.

> Given on how rarely I update to the latest development version of Emacs,
> I can't say anything more precise than that the problem was introduced
> during this summer.  I know, not very helpful.

Do you still have the previous binary you built?  Can you run it now
and make sure the problem does not exist in that binary?

> What do you mean with bisect?  Checkout earlier versions and test them
> until I find the bad commit?  Given the high volume of commits in Emacs
> this would take quite a while even when using an efficient
> search strategy.

Both bzr and git have a bisect command that will converge on the
offending revision logarithmically.  Since there were about 1000
commits since the beginning of the summer, you will need about 10
different builds.