compilation-scroll-output doesn't work if *compilation* buffer is created by hand

Question

Emacs version 25

I have a short piece of elisp to create a few buffers and split my frame into multiple windows that are displayed the way I like. This code creates a *compilation* buffer and dedicates it using this code:

;; https://stackoverflow.com/questions/5151620/how-do-i-make-this-emacs-frame-keep-its-buffer-and-not-get-resized
;; Toggle window dedication
(defun toggle-window-dedicated ()
  "Toggle whether the current active window is dedicated or not"
  (interactive)
  (message
   (if (let (window (get-buffer-window (current-buffer)))
         (set-window-dedicated-p window
                                 (not (window-dedicated-p window))))
       "Window '%s' is dedicated"
     "Window '%s' is normal")
   (current-buffer)))

(switch-to-buffer (get-buffer-create "*compilation*"))
(toggle-window-dedicated)

My issue is that when running a compilation, even if the compiler output goes to the correct buffer, the *compilation* buffer doesn't scroll automatically to always display the most recent text.

My configuration is (setq compilation-scroll-output 'first-error)

The normal scrolling behavior seems to only be enabled when the *compilation* buffer is created by the compile command and not by hand. Even if I make the window with this buffer dedicated latter.

Is there a correct way to create the *compilation* buffer without running the compile command but keeping the compilation-scroll-output configuration behavior?

EDIT: a more detailed procedure:

How to trigger the problem:

• put mybuffer.el and Makefile in one directory (/tmp/emacs_problem for example)
• open file mybuffer.el
• go to end of the create-my-buffers function and execute the code (C-x C-e)
• execute the create-my-buffers function with M-x create-my-buffers
• execute M-x compile RET RET

How to see the expected behavior:

• open file mybuffer.el
• execute M-x compile RET RET

The Makefile:

default:
    ls -1 /bin

mybuffer.el:

(defun create-my-buffers ()
  (interactive)
  (delete-other-windows)

  (setq total-window-size (window-width (frame-selected-window)))
  (setq total-window-height (window-height (frame-selected-window)))

  (split-window-vertically)
  (other-window 1)
  (switch-to-buffer (get-buffer-create "*compilation*"))
  (setq second-window-height (window-height (frame-selected-window)))
  (setq expected-window-height (* 0.10 total-window-height))
  (setq expand-window-height (- expected-window-height second-window-height))
  (enlarge-window (round expand-window-height))
  (other-window 1)
)

The result with the "bad" behavior, the window with the compilation buffer has not scrolled to the bottom:

The result with the good behavior, the cursor is at the end of the content and the window has scrolled correctly:

The output for M-x describe-mode after calling M-x compile is:

Enabled minor modes: Auto-Composition Auto-Compression Auto-Encryption
Autopair-Global Column-Number Company Company-Quickhelp
Company-Quickhelp-Local Delete-Selection Display-Time Electric-Indent
Evil-Matchit File-Name-Shadow Font-Lock Global-Auto-Revert
Global-Company Global-Eldoc Global-Evil-Matchit Global-Font-Lock
Global-Git-Gutter Global-Linum Global-Undo-Tree Global-Visual-Line
Global-Whitespace Hl-Line Line-Number Mouse-Wheel Save-Place
Shell-Dirtrack Show-Paren Tooltip Transient-Mark Undo-Tree Visual-Line

(Information about these minor modes follows the major mode info.)

Compilation mode defined in ‘compile.el’:
Major mode for compilation log buffers.
To visit the source for a line-numbered error,
move point to the error message line and type RET.
To kill the compilation, type C-c C-k.

Runs ‘compilation-mode-hook’ with ‘run-mode-hooks’ (which see).

EDIT 2: It seems that the scrolling is done correctly if I launch M-x compile from the window containing *compilation* rather than from the window containing mybuffer.el.

Answer 1

revision:

Since I wasn't able to recreate my former success (see the comments below), the only answer I can offer is that the output scrolling works only in two cases: either, if you run the compilation command from the compilation buffer, or, if you re-use the compilation buffer for a second compilation.

It is not clear to me why any setup with (compilation-mode "Compilation") or (compilation-setup) does not work; it seems to ignore any customized variables when the compile command does not create the buffer itself. Maybe this can be considered a bug and should be put into the Emacs bug tracker at gnu.org, if it is not already there. The instance when I was able to make it work must have been a lucky shot, but, as already said, I cannot recreate what I did manually –– sorry.