Re: [PATCH 1/2] Input: usbtouchscreen - suppress empty array warnings

[Dmitry Torokhov]

Hi Johan,

On Mon, Jun 20, 2022 at 10:46:27AM +0200, Johan Hovold wrote:
> When compile-testing the USB touchscreen driver without enabling any of
> the device type options the usbtouch_dev_info array ends up being empty,
> something which triggers compiler warning with -Warray-bounds
> (gcc-11.3.0).
> 
> drivers/input/touchscreen/usbtouchscreen.c: In function 'usbtouch_probe':
> drivers/input/touchscreen/usbtouchscreen.c:1668:16:warning: array subscript <unknown> is outside array bounds of 'struct usbtouch_device_info[0]' [-Warray-bounds]
>  1668 |         type = &usbtouch_dev_info[id->driver_info];
> 
> Suppress the warnings by making sure that the array is always non-empty.

Does it still warn if you add a check for type, something like

	if (type >= ARRAY_SIZE(usbtouch_device_info))
		return -ENODEV;

?

Thanks.

-- 
Dmitry