Re: [PATCH] fbcon: introduce for_each_registered_fb() helper

[Andy Shevchenko]

On Mon, 2018-07-02 at 09:30 +0200, Daniel Vetter wrote:
> On Fri, Jun 29, 2018 at 07:20:13PM +0300, Andy Shevchenko wrote:
> > On Fri, 2018-06-29 at 00:20 +0800, Yisheng Xie wrote:

> > LGTM except macro implementation. That's why I have mentioned
> > for_each_pci_bridge() to look at.
> > 
> > > +#define for_each_registered_fb(i)		\
> > > +	for (i = 0; i < FB_MAX; i++)		\
> > > +		if (registered_fb[i])
> > > +
> > 
> > This needs to be protected against nested conditionals.
> > Otherwise compiler issues a warning and even may generate wrong
> > code.
> 
> See for_each_if() in include/drm/drmP.h ... we should probably lift
> that
> into a general header. The for_each_if() is used all over drm in
> iterator
> macros, exactly to avoid surprises.

Wow, didn't know we have a such. It's a good idea to forelift it for
wider use.

Yisheng, it seems you may use it in your patch directly.

-- 
Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Intel Finland Oy