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Date: Tue, 14 May 2024 20:34:56 +0530
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Subject: Re: [PATCH 12/13] regulator: add pm8008 pmic regulator driver
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To: Andy Shevchenko <andy.shevchenko@gmail.com>
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From: "Satya Priya Kakitapalli (Temp)" <quic_skakitap@quicinc.com>
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On 5/14/2024 7:48 PM, Andy Shevchenko wrote:
> On Tue, May 14, 2024 at 5:05 PM Satya Priya Kakitapalli
> <quic_skakitap@quicinc.com> wrote:
>>> On Thu, May 09, 2024 at 03:07:02PM +0300, Andy Shevchenko wrote:
>>>> Wed, May 08, 2024 at 10:37:50PM +0000, Stephen Boyd kirjoitti:
>>>>> Quoting Johan Hovold (2024-05-06 08:08:29)
> ...
>
>>>>>> +               BUILD_BUG_ON((ARRAY_SIZE(pldo_ranges) != 1) ||
>>>>> This should be an && not || right?
>>>>>> +                               (ARRAY_SIZE(nldo_ranges) != 1));
>>>> In any case BUILD_BUG_ON() is not encouraged for such cases, it would be much
>>>> better to have a static_assert() near to one of those arrays.
>>> I think the reason it is placed here is that the above line reads:
>>>
>>>        rdesc->n_linear_ranges = 1;
>>>
>>> and that would need to change if anyone expands the arrays.
>> Correct. static_assert() cannot be used in the middle of code here, it can only be used at the declarations part which doesn't serve the purpose.
> I didn't get this. The ARRAY_SIZE():s are defined at compile time
> globally. How does this prevent from using static_assert()?


The reason we added it here is to make sure the nlod_ranges and 
pldo_ranges doesn't become larger, and we forget updating the 
n_linear_ranges. Adding static_assert here is not feasible so adding a 
BUILD_BUG_ON at this point makes sure the n_linear_ranges is proper.


>> So, BUILD_BUG_ON is the only way to go here.
> I don't think so.
>