bug#57529: 28.1; `C-c C-x' prefix key and keymap, `C-c C-x C-h'

[Eli Zaretskii]

> From: Drew Adams <drew.adams@oracle.com>
> Date: Thu, 1 Sep 2022 18:05:46 +0000
> 
> Dunno, but this seems like a bug (you decide):
> 
> https://emacs.stackexchange.com/q/73390/
> 
> `C-c' is a prefix key bound to `mode-specific-map', but it seems to be
> set up in C source code.

Why do you think it is set up in C?  "C-h v" tells me otherwise.

> `C-c C-x' is apparently defined (unlike, say,
> `C-c C-x 4') as a prefix key, but it's not clear what its keymap is (and
> it's apparently empty by default).
> 
> Dunno what changes should be made, to make clear to users what the story
> is - why, for example, `C-c C-x' just waits for another key, even though
> there's no such key defined in the keymap.
> 
> Maybe this is a more general "problem", for empty prefix keys?  Or is it
> a result of the prefix being defined in C?

There's a good answer on stackexchange for this "problem", and I'm not
sure what else would we need to do about this report except close it.