sftp access fails on Emacs master (Avahi?)

[Stephen Berman]

Since updating from master three days ago, I cannot access a remote
directory via the sftp method.  It was a bootstrap build, so I don't
have the previous executables, but I think my last build from master in
which sftp access succeeded was within the last two or three weeks.
There is no Tramp debug output despite setting tramp-verbose to 8, but
when I start Emacs with --debug-init, I get the attached backtrace,
which indicates the problem seems to be due to not having Avahi
installed.  But with emacs-27 there is no problem with sftp access,
although the Tramp debug output shows a D-bus error due to Avahi
missing:

;; Emacs: 27.0.60 Tramp: 2.4.3.27.1 -*- mode: outline; -*-
11:15:45.108247 tramp-file-name-handler (1) # D-Bus error: "D-Bus error", "The 
name org.freedesktop.Avahi was not provided by any .service files"
11:15:45.108768 tramp-file-name-handler (1) # D-Bus error: "D-Bus error", "The 
name org.freedesktop.Avahi was not provided by any .service files"
11:15:45.114011 tramp-get-connection-property (7) # case-insensitive undef
11:15:45.135938 tramp-get-file-property (8) # /b/bermasbp/ file-truename undef
11:15:45.139727 tramp-get-file-property (8) # /b/ directory-attributes undef
11:15:45.139796 tramp-gvfs-get-directory-attributes (5) # directory gvfs 
attributes: /b/
11:15:45.161117 tramp-call-process (6) # ‘locale -a’ nil  *temp*
11:15:45.161812 tramp-call-process (6) # 0

A possibly related datapoint: I enable recentf-mode on starting Emacs,
and the ~/.emacs.d/recentf file includes remote files accessed via sftp.
In current master *Messages* shows this:

Loading /home/steve/.emacs.d/recentf...done
Waiting for git... [2 times]
Error setting recentf-mode: (wrong-type-argument number-or-marker-p nil)

But in emacs-27 there is no such error.

Steve Berman

tramp-master
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