Viper tests failure?

[Fabrice Popineau]

Hi,

With emacs-25 commit e5e886d12f3eff3102916c82a5aa82e0db714579
Emacs compiled using Mingw64 I get a strange error
running `make check':

$ src/emacs --batch -Q -l ../emacs/test/automated/viper-tests.el --eval '(ert-
run-tests-batch t)'
Running 6 tests (2016-06-21 07:01:58+0200)
Loading viper...
Test viper-test-fix backtrace:
  byte-code(\204'\306\307\310!CB\301    CB\302\nCB\303
                                                      CB\311\307\311!
  load("viper")
  load-library("viper")
  viper-mode()
  (progn (viper-mode) (switch-to-buffer (get-buffer-create "*viper-tes
  (unwind-protect (progn (viper-mode) (switch-to-buffer (get-buffer-cr
  (let ((noninteractive nil) (viper-inhibit-startup-message (quote t))
  viper-test-undo-kmacro([])
  apply(viper-test-undo-kmacro [])
  (setq value-4 (apply fn-2 args-3))
  (unwind-protect (setq value-4 (apply fn-2 args-3)) (setq form-descri
  (if (unwind-protect (setq value-4 (apply fn-2 args-3)) (setq form-de
  (let (form-description-6) (if (unwind-protect (setq value-4 (apply f
  (let ((value-4 (quote ert-form-evaluation-aborted-5))) (let (form-de
  (let ((fn-2 (function viper-test-undo-kmacro)) (args-3 (list []))) (
  (lambda nil (let ((fn-2 (function viper-test-undo-kmacro)) (args-3 (
  ert--run-test-internal([cl-struct-ert--test-execution-info [cl-struc
  ert-run-test([cl-struct-ert-test viper-test-fix "Test that the viper
  ert-run-or-rerun-test([cl-struct-ert--stats t [[cl-struct-ert-test v
  ert-run-tests(t #[385 "\306\307\"address@hidden
  ert-run-tests-batch(t)
  eval((ert-run-tests-batch t))
  command-line-1(("-l" "../emacs/test/automated/viper-tests.el" "--eva
  command-line()
  normal-top-level()
Test viper-test-fix condition:
    (file-error "Opening stdio stream" "No such file or directory" 
"c:/Users/Fabrice/AppData/Local/Temp/viper-tests21052GpM")
   FAILED  1/6  viper-test-fix

I'm not sure what is happening there.
I checked the temp file is created and does exist, so why is there 
a failure to open it?

Regards,

Fabrice