lkml.org 
[lkml]   [2019]   [Jul]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [RFC PATCH] compiler_attributes.h: Add 'fallthrough' pseudo keyword for switch/case use
On Tue 2019-07-30 22:35:18, Joe Perches wrote:
> Reserve the pseudo keyword 'fallthrough' for the ability to convert the
> various case block /* fallthrough */ style comments to appear to be an
> actual reserved word with the same gcc case block missing fallthrough
> warning capability.

Acked-by: Pavel Machek <pavel@ucw.cz>

> +/*
> + * Add the pseudo keyword 'fallthrough' so case statement blocks
> + * must end with any of these keywords:
> + * break;
> + * fallthrough;
> + * goto <label>;
> + * return [expression];
> + *
> + * gcc: https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html#Statement-Attributes
> + */
> +#if __has_attribute(__fallthrough__)
> +# define fallthrough __attribute__((__fallthrough__))
> +#else
> +# define fallthrough do {} while (0) /* fallthrough */
> +#endif
> +

Will various checkers (and gcc) recognize, that comment in a macro,
and disable the warning accordingly?

Explanation that the comment is "magic" might not be a bad idea.

Thanks,

Pavel

--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
[unhandled content-type:application/pgp-signature]
\
 
 \ /
  Last update: 2019-07-31 19:14    [W:0.227 / U:0.856 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site