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

From: Andy Shevchenko
Date: Thu Apr 11 2024 - 06:31:38 EST


On Thu, Apr 11, 2024 at 09:30:31AM +0200, Geert Uytterhoeven wrote:
> 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

Thanks, I updated locally. Please, see my answer below.

> > for struct charlcd_ops before using it in struct charlcd.

..

> > +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.

The same way as in all other cases. We may drop all of them, but strictly
speaking (as I mentioned in the commit message) this is a good practice.

I.o.w. a forward declaration of custom data types is used for _pointers_.

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

--
With Best Regards,
Andy Shevchenko