bug#22884: 25.0.92; C/l mode editing takes waaaayy too long

[Paul Eggert <eggert@cs.ucla.edu>]

On 03/03/2016 11:23 AM, Alan Mackenzie wrote:
> Why only for the one file?

Because I didn't have time to fix all the source files (I was about to 
rush off and teach a class....). It could easily be added, at least for 
files we maintain. Though, as Eli says, it'd be nicer if cc-mode didn't 
think lines beginning with '(' were relevant for function-start in C.

> The performance hit comes from the amount of contiguous syntactic 
> whitespace following the "failed" comment. Have you checked this is 
> the only file with so much SWS?

No. It's easier for me to simply fix all instances of code that have '(' 
at line start. I can propose a more-complete patch along those lines.

>
> OK.  Could you give me a clue as to what they mean, please?  For
> example, in
>
>      INLINE EMACS_INT
>      (XLI) (Lisp_Object o)
>      {
>        return lisp_h_XLI (o);
>      }
>
> , what does "(XLI)" do?

It defines a function named 'XLI' even though there's also a 
function-like macro named 'XLI', without expanding the macro.

> No, they don't cause breakage.

Good, in that case we can leave them alone.