Re: [PATCH v1 2/2] auxdisplay: charlcd: Provide a forward declaration

[Geert Uytterhoeven]

Hi Andy,

On Tue, Apr 9, 2024 at 6:15 PM Andy Shevchenko
<andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
> While there is no compilation error, strictly speaking compiler
> should know about used types beforehand. Provide a forward decoration

declaration

> for struct charlcd_ops before using it in struct charlcd.
>
> Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

> --- a/drivers/auxdisplay/charlcd.h
> +++ b/drivers/auxdisplay/charlcd.h
> @@ -36,6 +36,8 @@ enum charlcd_lines {
>         CHARLCD_LINES_2,
>  };
>
> +struct charlcd_ops;
> +
>  struct charlcd {
>         const struct charlcd_ops *ops;

No forward declaration is needed at this point, as ops is a _pointer_ to
the structure.

>         const unsigned char *char_conv; /* Optional */

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68korg

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds