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Date:   Fri, 21 Oct 2022 04:19:06 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Maria Yu <quic_aiquny@quicinc.com>
Cc:     akpm@linux-foundation.org, ziy@nvidia.com, david@redhat.com,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        mike.kravetz@oracle.com, opendmb@gmail.com, stable@vger.kernel.org
Subject: Re: [PATCH] mm/page_isolation: fix clang deadcode warning
Message-ID: <Y1IPqhVpiehRBGNS@casper.infradead.org>
References: <20221021030953.34925-1-quic_aiquny@quicinc.com>
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On Fri, Oct 21, 2022 at 11:09:53AM +0800, Maria Yu wrote:
> When !CONFIG_VM_BUG_ON, there is warning of
> clang-analyzer-deadcode.DeadStores:
> Value stored to 'mt' during its initialization
> is never read.

Honestly, the cure is worse than the disease.  I'd rather not have a
line that's this long.

> -		int mt = get_pageblock_migratetype(pfn_to_page(isolate_pageblock));
> -
> -		VM_BUG_ON(!is_migrate_isolate(mt));
> +		VM_BUG_ON(!is_migrate_isolate(get_pageblock_migratetype(pfn_to_page(isolate_pageblock))));