So I spend some more time on this today. Its painful to keep scrolling forever but I think I have found a pattern that works reliably.

Open emacs with a specific header file from command line. /usr/local/Cellar/emacs-head/HEAD-86fef6a_1/Emacs.app/Contents/MacOS/Emacs /personal/roar_engine/core/rhi/rorrhi_types.hpp
M-x split-window-horizontally and start scrolling between the two windows interchangeably.

I did a binary search through my packages but it was inconclusive. It appeared with single package, but different single packages at different times. So I started commenting out my whole init.el file.

(setq user-full-name "Wasim Abbas")
(setq user-mail-address "abbas.wasim@gmail.com")

;; load my sexp from elisp dir
(add-to-list 'load-path (expand-file-name "elisp" user-emacs-directory))
;; add custom theme folder to load themes from ~/.emacs.d/themes
(add-to-list 'custom-theme-load-path (expand-file-name "themes" user-emacs-directory))

This is the only snippet that I can reproduce it with. This doesn’t make much sense. I am not using any themes later on. The whole init.el is empty after these lines. I have reproduced it with this a few times.
Although I have still not managed to reproduce it with `-Q` option yet.

Also at one point I got the following segfault.



//Wasim

On 10 Aug 2020, at 20:11, Alan Third <alan@idiocy.org> wrote:

On Mon, Aug 10, 2020 at 12:40:31PM +0100, Wasim Abbas wrote:
I thought since drawing buffers and rendering is such a core thing
to emacs I wasn’t sure it will be anything else (like a package) but
looks like it could be? Would you now think it's something to do
with any package?

It's unlikely to be a package directly causing it, but it may be doing
something which causes a bug in Emacs itself to show.

Is the standard disable each package one by one and see if it can be
narrowed down to a single package the way to go forward now?

The usual way would be a binary search type strategy. Comment out half
your config, then see if you still have the problem, if not try the
other half. Then you half what remains, and repeat until you've found
the cause.

The problem is that it may be a combination of things that are causing
it, but at least it may give us a chance to get a minimal recipe to
replicate the bug.
--
Alan Third