Re: Font-lock decides function call is function declaration in C+ +

[Alan Mackenzie <acm@muc.de>]

Hi, Simon!

On Mon, Feb 05, 2007 at 04:46:32PM -0000, Marshall, Simon wrote:
> > Does this bug still exist with latest CVS?  If so, please provide a
> > simple test case (I couldn't find one in your previous messages).

> Yes, it does, with CVS Emacs as of 05/02/2007.  Originally, I couldn't
> reproduce it on demand.  That's why, originally, I was asking for help to
> track it down.

> But, messing around just now, I've finally managed to do it.  I can't say
> that these are the only way of reproducing it, as I've seen this
> misfontification in a variety of situations that do not look obviously like
> these.

> 1.  The goal is to write the code snippet:

> int main() {
>   foo();
>   bar();
> }

> emacs -Q foo.cpp
> int SPC main() SPC { RET } RET C-p C-o bar();

> OK so far.  Now to insert the "foo();" line:

> C-a C-o foo

> At this point, "foo" is fontified as a type, and "bar" as a variable.  OK.
> Now:

> ()

> The fontification of "foo" and "bar" disappears.  OK.  Now complete the
> snippet:

> ;

> Now "foo" is fontified as a variable.  This is wrong.

It is indeed wrong.  

Further observations:
(i) The bug doesn't happen in C Mode.
The bug happens:
(ii) in Emacs 5.21.3/CC Mode 5.31.4
(iii) With jit-lock disabled (thankfully ;-)
(iv) in Emacs 5.21.3/CC Mode 5.30.3

So it seems its entirely a CC Mode bug.  I'm going to try and track it
down, though I suspect it could be quite tricky to find.  Thanks for
giving that recipe for producing the bug.

> 2.  Here's a variation.  [ snipped ]

> What is worse is that in both cases I cannot get rid of the
> misfontification without turning Font Lock mode off and on again.

M-o M-o fixes the fontification for me.

> I hope this help to fix The Most Annoying Fontification Bug Ever.
> Simon.

I think there're also other candidates for that description.  ;-(

-- 
Alan Mackenzie (Ittersbach, Germany).