Re: cc-mode fontification feels random

[Stefan Monnier]

> Will Emacs 27.2 do?  If you must see results from an optimized build
> of Emacs 28, I'll have to build one first.

As mentioned, mine was not an optimized build, on the contrary.

>> FWIW, I ran this same test with `sm-c-mode` (which should handle `xdisp.c`
>> about as well as CC-mode, but solves an easier problem since it doesn't
>> try to handle as much of C as CC-mode does (e.g. no support for K&R, no
>> highlighting of types), nor does it try to handle C++, Java, ...), and
>> most of the times for it are between 0.02 and 0.04.
>
> That is much better, but still too slow, IMO.  Think: it's the time
> that it takes us to fontify a single windowful, only a couple of
> dozens of lines.  Why does it take so long?

For comparison, here it is for lisp/subr.el: it seems actually slightly
slower than what I for with xdisp.c when using sm-c-mode.


        Stefan


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