bug#28098: 26.0.50; bad C fontification

[Alan Mackenzie]

Hello, Marti.

In article <mailman.13159.1502810889.21957.bug-gnu-emacs@gnu.org> you wrote:
> [-- text/plain, encoding 7bit, charset: UTF-8, 98 lines --]

> 1. From emacs -Q, open this file:


> https://github.com/zephyrproject-rtos/zephyr/blob/2de59023dc726e61244eb7cca17252294016c65a/subsys/net/lib/http/http_client.c

> 2. Observe incorrect syntax highlighting at beginning of file. Screenshot:

>    https://postimg.org/image/tzy8qgjjz/

More precisely, the first ~500 bytes, which consist entirely of comments
and preprocessor directives doesn't get fontified at all.

>    (Note that loading a C file with just the #ifdefs and initial
>    comment which fail to highlight above doesn't reproduce the issue.)

Thanks.  The fact that it's ~500 bytes which don't get fontified suggest
that something is interfering with the first jit-lock chunk.  I'll be
looking into it.  Give me a bit of time.

> In GNU Emacs 26.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.22.11)
>  of 2017-08-10 built on plop
> Repository revision: 81656add8117e8d1b7faab18b330d0706462b433
> Windowing system distributor 'The X.Org Foundation', version 11.0.11903000
> System Description: Ubuntu 17.04

[ .... ]

-- 
Alan Mackenzie (Nuremberg, Germany).