Re: display margin errors on a tty

[Chong Yidong]

Richard Stallman <address@hidden> writes:

>     It forces a glyph matrix reallocation after each call to
>     enlarge_window.  The slowdown will be undetectable since redisplay is
>     so fast on text terminals anyway.
>
> I think this is a good solution, if it works.  It is simple, and it is
> safe.  And the slowdown is insignificant compared with everything else
> that is going on when you change window sizes.
>
> However, KFS wrote
>
>     No, the problem seems to come up as long as there is a window with a
>     marginal area in use.
>
> Does that mean your fix doesn't actually solve the problem?

It papers over it.  An optimization in dispnew.c gets screwed up when
display margins are present for terminal display.  I just checked in a
patch that basically disables the optimization when we are in that
situation.

So it's not *really* solving the problem.  But it's a lot safer, and
AFAICT it completely prevents the problem from appearing.  So we can
probably live with it for now.