Re: Problem after upgrading to 13.1.3

[Arash Esbati]

Greg Bognar via General discussion about AUCTeX <auctex@gnu.org> writes:

> I've just upgraded to 13.1.3 from ELPA.  I'm on Emacs 27.1.
>
> When I open a LaTeX file, it opens in something called Fundamental mode.  But 
> I
> do actually get font-locking and the basic AUCTeX menus, but none of my
> customizations seem to have loaded.  C-c C-c asks for the master file, even
> though TeX-master is set in the file-local variables.  M-x describe-mode tells
> me:
>
>    Fundamental mode defined in `tex-mode.el':
>    This function has :override advice: `TeX-latex-mode'.
>
> I use use-package to load AUCTeX:
>
>    (use-package tex
>      :ensure auctex
>      :defer t
>      :mode ("\\.tex\\'" . LaTeX-mode)
>      [...]
>
> When I try to change the mode of the file by M-x LaTeX-mode, I get an error:
>
>    Cannot open load file: No such file or directory, tex-buf

tex-buf.el is gone and its content is now in tex.el.  I suspect you have
still some configuration around which looks for tex-buf.el explicitly.
Also looking for load-path shadows with 'M-x list-load-path-shadows RET'
could help.

One other thing is if you're using an Emacs distro like Prelude,
Spacemacs, Doom et al. and they try to load tex-buf.el.  I remember
there were reports in that area.

> My setup has worked without any problems before the upgrade.  It seems
> use-package does not load AUCTeX properly, although this is the way 
> recommended
> in the manual.  I should also say I have a cryptic comment in my init file:
>
>      :ensure auctex ;FIXME: cannot be installed automatically
>
> But I can't remember what problem I was trying to fix.

I don't use use-package so I can't tell.

Best, Arash