Re: [PATCH][next] wil6210: Avoid the use of one-element array

[Gustavo A. R. Silva]

On 7/22/20 14:40, Johannes Berg wrote:
> On Wed, 2020-07-15 at 16:57 -0500, Gustavo A. R. Silva wrote:
>> One-element arrays are being deprecated[1]. Replace the one-element
>> array with a simple value type 'u8 reserved'[2], once this is just
>> a placeholder for alignment.
>>
>> [1] https://github.com/KSPP/linux/issues/79
>> [2] https://github.com/KSPP/linux/issues/86
> 
> Umm, no, you're misinterpreting this ... This has nothing to do with
> variable length and isn't used that way. As you can see from your own
> patch, since you're not changing any users.
> 

I understand that this 'reserved' field is being used merely for alignment
purposes:

drivers/net/wireless/ath/wil6210/wmi.h:

3080 /* WMI_SCHEDULING_SCHEME_EVENTID */
3081 struct wmi_scheduling_scheme_event {
3082         /* wmi_fw_status_e */
3083         u8 status;
3084         /* serial number given in command */
3085         u8 serial_num;
3086         /* wmi_sched_scheme_failure_type */
3087         u8 failure_type;
3088         /* alignment to 32b */
3089         u8 reserved[1];
3090 } __packed;

and that it's not being used as a variable-length array. The links are included
to inform the people about the reason why we are removing zero-length/one-element
arrays in the first place. The thing in this case is that it doesn't hurt to use
a simple value type instead of the one-element array form.

Thanks
--
Gustavo