bug#26932: 25.1; Crash triggered a few times a day with network process

[Vivek Dasmohapatra]

> What kind of :eval form(s) do you have in your mode-line-format
> definitions?

At the top level of m-l-f

 ;; 2nd element:
 (:eval
   (if
       (display-graphic-p)
       #(" " 0 1
         (help-echo "mouse-1: Select (drag to resize)\nmouse-2: Make current
                     window occupy the whole frame\nmouse-3: Remove current
                     window from display"))
     #("-" 0 1
       (help-echo "mouse-1: Select (drag to resize)\nmouse-2: Make current
                   window occupy the whole frame\nmouse-3: Remove current
                   window from display"))))

Immediately followd by:

 ;; mode-line-mule-info
 ;; which ends with:
  (:eval
    (mode-line-eol-desc))

 ;; mode-line-client
 ("" (:propertize
       ("" (:eval
            (if (frame-parameter nil 'client) "@" "")))

 ;; mode-line-modified - N/a
 ;; mode-line-remote - N/a

 ;; mode-line-frame-identification
 (:eval (mode-line-frame-control))

 ;; mode-line-buffer-identification - N/a

 ;; Final element:
(:eval
  (unless
      (display-graphic-p)
    #("-%-" 0 3
      (help-echo "mouse-1: Select (drag to resize)\nmouse-2: Make current
                  window occupy the whole frame\nmouse-3: Remove current
                  window from display"))))