How to debug c-mode-common-hook that doesn't fire

Question

I'm using prelude mode, and in a file .emacs.d/personal/old-settings.el I have, amongst other things:

(global-set-key (kbd "C-c C-c") 'comment-region)

(add-hook 'c-mode-common-hook
      (lambda()
        (local-set-key  (kbd "C-c o") 'ff-find-other-file)))

Now when editing a c++-mode file, comment-region has been set, but ff-find-other-file hasn't.

I did F1 v c-mode-common-hook and see this:

c-mode-common-hook is a variable defined in `cc-vars.el'.
Its value is ((lambda nil
   (local-set-key
   (kbd "C-c o")
   'ff-find-other-file))
(lambda nil
  (run-hooks 'prelude-c-mode-common-hook)))

How would I go about debugging this? There doesn't seem to be a way to list-hooks, detect if the hook had already fired, etc.

Answer 1

1. You could print a message from your hook, like this:

   (add-hook 'c-mode-common-hook (lambda() (message "fired") (local-set-key (kbd "C-c o") 'ff-find-other-file)))

2. You can have a look at the current mode and his Key-Bindings with C-h m

3. You can write a short config.el which only handels the Part you try to debug and start it with emacs -Q -l config.el

Btw: I have done all 3 steps above and the hook fires.

Can someone help me formating this code-snippet? :)