The change of `tramp.el' of 2006-01-27 hoses all emacsen I know. As part of <Sync with Tramp 2.0.53> of 2006/04/17 13:11:42 +0 it got into xemacs packages cvs, so cc-ing to its maintainers. Reproducing it as follows. xemacs -vanilla -batch -eval '(let ((default-directory "/")) (write-region (point-min) (point-max) "/dev/null" nil (quote silent)))' Lisp nesting exceeds `max-lisp-eval-depth' xemacs exiting . After `tramp' with this change is installed and emacs is started, it loads autoload files, which add to `file-name-handler-alist' an association of `tramp-completion-file-name-handler' with "^/\\([[][^]]*\\)?$", regexp that matches `/'. `tramp-completion-file-name-handler' is autoloaded, and `tramp' defining it is not loaded yet. `expand-file-name' calls file name handler even if its DEFAULT-DIRECTORY argument matches the regexp from `file-name-handler-alist'. And `expand-file-name' is called in many cases, even in the following backtrace. (Line numbers are from local xemacs 21.4 with local changes.) Fexpand_file_name at src/fileio.c:810 locate_file at src/lread.c:1246 Flocate_file at src/lread.c:873 locate-file("tramp" ;regular `load-path value (".elc" ".el" "")) load("tramp" nil nil nil) If at this point it is not obvious how emacs gets into infinite recursion, detailing it. Once something calls `expand-file-name' with DEFAULT-DIRECTORY set to `/' (by passing explicitly or by defaulting to that value when `nil' is passed) in a buffer with default directory value `/', emacs does the following. . Calls `tramp-completion-file-name-handler'. . Processes autoload. . Tries to load `tramp'. . Calls `expand-file-name' with the same DEFAULT-DIRECTORY '/'. `gnus' package (temporarily) sets `default-directory' to '/' during (implicit) `expand-file-name' call, like in the example above. Will post details on request. Please fix `tramp' so that `/' is not matched by (tramp regexps from) `file-name-handler-alist' before `tramp' is loaded. Maintainers may have their own ideas how this should be ensured, and how the safe regexp not matching `/' should be computed, so do not submitting a patch.