bug#42655: 27.1; iconify-frame on a Lucid build may stuck the frame

[Bhavin Gandhi]

On Tue, 4 Aug 2020 at 22:11, Eli Zaretskii <eliz@gnu.org> wrote:
>
> And when you do create a new frame, do you see the redraw-display
> command in the command history?  Also, what does "C-h l" show in that
> other frame?

Yes, I can see the redraw-display command in command-history. This is
what "C-h l" shows.

--8<---------------cut here---------------start------------->8---
 C-z                    ;; suspend-frame
 M-x                    ;; execute-extended-command
 r                      ;; self-insert-command
 e                      ;; self-insert-command
 d                      ;; self-insert-command
 r                      ;; self-insert-command
 <return>               ;; minibuffer-complete-and-exit
 C-x 5 2                ;; make-frame-command
 ;; handle-switch-frame
 C-h l                  ;; view-lossage
--8<---------------cut here---------------end--------------->8---

> If you now attach a debugger to Emacs, what does the backtrace show?

Is running "gdb -i=mi -p PID" enough to generate this backtrace?