Hi,

        While testing `make-network-process' from the example
        given in bug#23658, Emacs crashed.

0. emacs -Q

1. Evaluate the following elisp:

   (progn
     (defun my-sentinel (proc event)
       (with-current-buffer "*scratch*"
         (save-excursion
           (goto-char (point-max))
           (insert (format "\n>> proc = '%s', status = '%s', event = '%s'"
                           proc (process-status proc) event)))))

     (defun my-filter (proc str)
       (with-current-buffer "*scratch*"
         (save-excursion
           (goto-char (point-max))
           (insert (format "\n>> proc = '%s', status = '%s', str = '%s'"
                           proc (process-status proc) str)))))

     ;; These IP addresses are both for host rajaniemi.freenode.net.
     (let* ((ipv6-host "2001:708:40:2001:a822:baff:fec4:2428")
            (ipv4-host "195.148.124.79")
            (process (make-network-process :name "zzz"
                                           :buffer nil
                                           :host ipv6-host
                                           ;; :host ipv4-host
                                           :service 6667
                                           :nowait t)))
       (set-process-sentinel process 'my-sentinel)
       (set-process-filter process 'my-filter)))


You should get the error:

Wrong type argument: processp, nil

      However, in my Emacs session I had:

2. (setq debug-on-error t)

   which made the Emacs session crash.

   The crash doesn't happen with an IPV4 addresses, just IPV6 addresses.

Thanks.