bug#16923: 24.3.50; reression: `set-frame-size' loses mode line

[Drew Adams <drew.adams@oracle.com>]

[-- Attachment #1: Type: text/plain, Size: 2624 bytes --]

Trying to pick up this bug thread again.  I'm afraid your last mail
is confusing to me at this point.

This is what I've done for this test:

1. Ensure, I think, that the only calls to `set-frame-size' are from
my calling `fit-frame' interactively (via C-x C-_).  Nothing on
`post-command-hook' that invokes `set-frame-size', for instance.

2. Resized a frame manually (with the mouse), so that the next call
to `fit-frame' would actually change the size (to fit the buffer text).

3. C-x C-_ (`fit-frame'), which fit the frame, with no loss of the
mode line.

4.  C-x C-_ again, which fit the frame (as a no-op, no size change
needed), this time with loss of the mode line (the bug).

Attached is the log, *window-frame-dump*.  After #3, I added a
line of zeros to the buffer, to make clear where the second call to
`fit-frame' (hence `set-frame-size') occurred.

The relevant lines from `fit-frame' are these:

(with-current-buffer (get-buffer-create "*window-frame-dump*")
  (insert (format "::: Requested WIDTH: %S, HEIGHT: %S\n" wid hgt)))
(set-frame-size frame wid hgt))))))

And this is the `window-dump-frame' code I used:

(defun window--dump-frame (&optional window-or-frame)
  "..."
  (interactive)
  (let* ((window
	  (cond
	   ((or (not window-or-frame)
		(frame-live-p window-or-frame))
	    (frame-root-window window-or-frame))
	   ((or (window-live-p window-or-frame)
		(window-child window-or-frame))
	    window-or-frame)
	   (t
	    (frame-root-window))))
	 (frame (window-frame window)))
    (with-current-buffer (get-buffer-create "*window-frame-dump*")
      ;;(erase-buffer)
      (insert
       (format "\nframe pixel: %s x %s   cols/lines: %s x %s   \
units: %s x %s\n"
	       (frame-pixel-width frame) (frame-pixel-height frame)
	       (frame-total-cols frame) (frame-text-lines frame)
	       (frame-char-width frame) (frame-char-height frame))
       (format "frame text pixel: %s x %s   cols/lines: %s x %s\n"
	       (frame-text-width frame) (frame-text-height frame)
	       (frame-text-cols frame) (frame-text-lines frame))
       (format "tool: %s  scroll: %s  fringe: %s  border: %s  \
right: %s  bottom: %s\n"
	       (tool-bar-height frame t)
	       (frame-scroll-bar-width frame)
	       (frame-fringe-width frame)
	       (frame-border-width frame)
	       (frame-right-divider-width frame)
	       (frame-bottom-divider-width frame))
       (format "w32-rect: %S, %S\n"
               (w32-frame-rect frame)
               (w32-frame-rect frame t)))
      (walk-window-tree 'window--dump-window frame t t))))

HTH.

[-- Attachment #2: throw-bug-16923-2014-03-27a.txt --]
[-- Type: text/plain, Size: 2543 bytes --]

------------

frame pixel: 511 x 528   cols/lines: 73 x 44   units: 7 x 12
frame text pixel: 490 x 528   cols/lines: 70 x 44
tool: 0  scroll: 21  fringe: 0  border: 0  right: 2  bottom: 2
w32-rect: (0 0 519 608), (0 0 511 528)
#<window 14 on throw-fit-frm.el>   parent: nil
pixel left: 0   top: 0   size: 511 x 528   new: 0
char left: 0   top: 0   size: 73 x 44   new: 0
normal: 1.0 x 1.0   new: 0
body pixel: 490 x 514   char: 70 x 42
width left fringe: 0  left margin: 0  right margin: 0
width right fringe: 0  scroll-bar: 21  divider: 0
height header-line: 0  mode-line: 14  divider: 0

::: Requested WIDTH: 101, HEIGHT: 69

frame pixel: 728 x 828   cols/lines: 104 x 69   units: 7 x 12
frame text pixel: 707 x 828   cols/lines: 101 x 69
tool: 0  scroll: 21  fringe: 0  border: 0  right: 2  bottom: 2
w32-rect: (0 0 736 884), (0 0 728 804)
#<window 14 on throw-fit-frm.el>   parent: nil
pixel left: 0   top: 0   size: 728 x 828   new: 0
char left: 0   top: 0   size: 104 x 69   new: 0
normal: 1.0 x 1.0   new: 0
body pixel: 707 x 814   char: 101 x 67
width left fringe: 0  left margin: 0  right margin: 0
width right fringe: 0  scroll-bar: 21  divider: 0
height header-line: 0  mode-line: 14  divider: 0

0000000000000000000000000000000000000000000000000000000

------------

frame pixel: 728 x 804   cols/lines: 104 x 67   units: 7 x 12
frame text pixel: 707 x 804   cols/lines: 101 x 67
tool: 0  scroll: 21  fringe: 0  border: 0  right: 2  bottom: 2
w32-rect: (0 0 736 884), (0 0 728 804)
#<window 14 on throw-fit-frm.el>   parent: nil
pixel left: 0   top: 0   size: 728 x 804   new: 0
char left: 0   top: 0   size: 104 x 67   new: 0
normal: 1.0 x 1.0   new: 0
body pixel: 707 x 790   char: 101 x 65
width left fringe: 0  left margin: 0  right margin: 0
width right fringe: 0  scroll-bar: 21  divider: 0
height header-line: 0  mode-line: 14  divider: 0

::: Requested WIDTH: 101, HEIGHT: 69

frame pixel: 728 x 828   cols/lines: 104 x 69   units: 7 x 12
frame text pixel: 707 x 828   cols/lines: 101 x 69
tool: 0  scroll: 21  fringe: 0  border: 0  right: 2  bottom: 2
w32-rect: (0 0 736 884), (0 0 728 804)
#<window 14 on throw-fit-frm.el>   parent: nil
pixel left: 0   top: 0   size: 728 x 828   new: 0
char left: 0   top: 0   size: 104 x 69   new: 0
normal: 1.0 x 1.0   new: 0
body pixel: 707 x 814   char: 101 x 67
width left fringe: 0  left margin: 0  right margin: 0
width right fringe: 0  scroll-bar: 21  divider: 0
height header-line: 0  mode-line: 14  divider: 0