> On Nov 4, 2022, at 08:32, Po Lu <luangruo@yahoo.com> wrote:
> 
> Kai Ma <justksqsf@gmail.com <mailto:justksqsf@gmail.com>> writes:
> 
> I am sorry, but this patch breaks compose processing.  So we're
> certainly not installing anything like this in Emacs 29.
> 
> I will try to figure out a way to reproduce the bug and why it actually
> happens.

Thanks!

I’ve narrowed the problem further to [firstRectForCharRange]. Some calls never return. Activating an input method makes Emacs issue excessive calls to this method. Specifically, the following code gets stuck somewhere.

  if (WINDOWP (echo_area_window) && ! NILP (call0 (intern ("ns-in-echo-area"))))
    win = XWINDOW (echo_area_window);
  else
    win = XWINDOW (FRAME_SELECTED_WINDOW (emacsframe));