I got the below error when running "make -j8 check-expensive".  This
seems to be intermittent.  It didn't show up on a second run or several
runs previous to the failing one.

I've attached "tramp-tests.log".  This is running on latest master on
Debian GNU/Linux.

Please let me know if you need any more information.

cmd: (/bin/sh -i)
buf:

---
Test tramp-test31-interrupt-process backtrace:
  signal(ert-test-failed ("`tramp-test31-interrupt-process' timed out"
  ert-fail("`tramp-test31-interrupt-process' timed out")
  tramp--test-timeout-handler()
  (progn (tramp--test-timeout-handler))
  (if (eq -with-timeout-value- 'timeout) (progn (tramp--test-timeout-h
  (let ((-with-timeout-value- (catch 'timeout (let* ((-with-timeout-ti
  (progn (setq proc (start-file-process-shell-command "test" (current-
  (unwind-protect (progn (setq proc (start-file-process-shell-command
  (save-current-buffer (set-buffer temp-buffer) (unwind-protect (progn
  (let ((temp-buffer (generate-new-buffer " *temp*"))) (save-current-b
  (unwind-protect (let ((temp-buffer (generate-new-buffer " *temp*")))
  (let ((default-directory (file-truename tramp-test-temporary-file-di
  (closure (ange-ftp-make-backup-files t) nil (let* ((fn-5416 #'tramp-
  ert--run-test-internal(#s(ert--test-execution-info :test #s(ert-test
  ert-run-test(#s(ert-test :name tramp-test31-interrupt-process :docum
  ert-run-or-rerun-test(#s(ert--stats :selector ... :tests ... :test-m
  ert-run-tests((not (tag :unstable)) #f(compiled-function (event-type
  ert-run-tests-batch((not (tag :unstable)))
  ert-run-tests-batch-and-exit((not (tag :unstable)))
  eval((ert-run-tests-batch-and-exit '(not (tag :unstable))) t)
  command-line-1(("-L" ":." "-l" "ert" "-l" "lisp/net/tramp-tests.el"
  command-line()
  normal-top-level()
Test tramp-test31-interrupt-process condition:
    (ert-test-failed "`tramp-test31-interrupt-process' timed out")
   FAILED  44/69  tramp-test31-interrupt-process (10.422236 sec)