bug#54491: 27.2; left-margin variable breaks autoload generation

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Date: Mon, 21 Mar 2022 16:19:20 +0100
> Cc: 54491@debbugs.gnu.org
> 
> (autoload 'allout-widgets-mode "allout-widgets" "\
> ("Toggle Allout Widgets mode.
> 
>       This is a minor mode.  If called interactively, toggle the
>       `Allout-Widgets mode' mode.  If the prefix argument is
>       positive, enable the mode, and if it is zero or negative,
>       disable the mode.
> 
> 
> 
> instead of
> 
> 
> (autoload 'allout-mode "allout" "\
> Toggle Allout outline mode.
> 
> This is a minor mode.  If called interactively, toggle the `Allout
> mode' mode.  If the prefix argument is positive, enable the mode, and
> if it is zero or negative, disable the mode.
> 
> 
> (Although you may find it difficult to then actually build Emacs
> afterwards.)
> 
> I haven't tried debugging further -- is it obvious to anybody else
> what's breaking here?

Looks like adaptive-fill?  lisp-mode defines various indent-* and
fill-* functions, so perhaps the extra open parenthesis is the
"prefix" it decides to use when filling/indenting?