Re: [PATCH v4 1/9] mm/swap: fix uninitialized compiler warning

[Alex Shi]

å 2019/11/19 äå11:41, Johannes Weiner åé:
> On Tue, Nov 19, 2019 at 08:23:15PM +0800, Alex Shi wrote:
>>   ../mm/swap.c: In function â__page_cache_releaseâ:
>>   ../mm/swap.c:67:10: warning: âflagsâ may be used uninitialized in this
>>   function [-Wmaybe-uninitialized]
>>        lruvec = lock_page_lruvec_irqsave(page, pgdat, flags);
>>        ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> At this point in the series, there is no lock_page_lruvec_irqsave()
> yet, so this patch is out of order. Please don't do that. It's very
> hard to review patches that depend on later changes to make sense.
> 

Sorry, I will be more careful on this.

>> Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx>
>> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
>> Cc: linux-mm@xxxxxxxxx
>> Cc: linux-kernel@xxxxxxxxxxxxxxx
>> ---
>>  mm/swap.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/mm/swap.c b/mm/swap.c
>> index 5341ae93861f..c36a10244d07 100644
>> --- a/mm/swap.c
>> +++ b/mm/swap.c
>> @@ -62,7 +62,7 @@ static void __page_cache_release(struct page *page)
>>  	if (PageLRU(page)) {
>>  		pg_data_t *pgdat = page_pgdat(page);
>>  		struct lruvec *lruvec;
>> -		unsigned long flags;
>> +		unsigned long flags = 0;
> Use unintialized_var() for these cases to make the intent clear.

Thanks for suggestion!