I can reproduce this bug in Emacs 21.4a-1, it indeed results in a segmentation fault.
Trying it with Emacs from CVS results in the following backtrace: Debugger entered--Lisp error: (error "Lisp nesting exceeds `max-lisp-eval-depth'") x-set-cut-buffer("\n" t) x-select-text("\n" t) kill-new("\n") copy-region-as-kill(3 4) byte-code("� \"� ��!�� ��pC\"" [beg end this-command kill-read-only-ok copy-region-as-kill kill-region message "Read only text copied to kill ring" nil barf-if-buffer-read-only signal text-read-only] 3) kill-region(3 4) kill-line() whitespace-buffer-trailing-cleanup() [... this line repeated 300 times ...] whitespace-buffer-trailing-cleanup() eval((whitespace-buffer-trailing-cleanup)) eval-expression((whitespace-buffer-trailing-cleanup) nil) call-interactively(eval-expression) I'll report this bug upstream. Thanks, -- ,''`. : :' : Romain Francoise <[EMAIL PROTECTED]> `. `' http://people.debian.org/~rfrancoise/ `-