Happened again. See attached `BACKTRACE' and `TRAMP-LOG' generated after evalling `(setf tramp-verbose 10)'.

Note this suspicious entry in the log:
10:26:36.864700 tramp-get-remote-tmpdir (1) # File error: Directory /ssh:USER@HOST#22222:/ssh:USER@HOST#22222:/tmp not accessible

Mentioned Git commit cannot be found, because I build Emacs with a few minor local changes. I can assure you they have nothing to do with TRAMP. The build is from 14th of September, so upstream commit number should be around 997284d2a5 or so.

I will keep this Emacs instance around in case you have questions.

Paul

On Thu, 29 Sept 2022 at 19:39, Michael Albinus <michael.albinus@gmx.de> wrote:
Paul Pogonyshev <pogonyshev@gmail.com> writes:

Hi Paul,

> No, the bug is not reproducible all the time. I have switched to Emacs
> 28 since then, as this breaks functionality important for me. Now
> tried to run 29 again, but it doesn't happen anymore, neither with
> `-Q' nor without. Also cannot find a backtrace for the same reason
> now.
>
> From the reproducing early today I remember that restarting Emacs
> doesn't help - or is at least random, since now a newly started Emacs
> doesn't exhibit this problem. It feels like the problem is in some
> cache and the cache appears to be persistent (cross-Emacs), if TRAMP
> uses something like that at all.
>
> The files I have noticed this on have names like
> "/ssh:USER@HOST#22222:/...", i.e. using SSH backend and a non-standard
> port, if that matters.

Thanks, this might make a difference when caching files. Ports are used
for creating a file name index in the cache, but I'm not certain they
are always taken into account, in all dark corners of Tramp. Will analyze.

However, it would be great if you could reproduce the bug somehow in an
Emacs instance started with

--8<---------------cut here---------------start------------->8---
emacs -Q --eval '(setq tramp-verbose 10)'
--8<---------------cut here---------------end--------------->8---

If the problem happens, pls show the recipe to provoke, and the Tramp
debug buffer.

> Paul

Best regards, Michael.