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Date:   Thu, 14 Jul 2022 13:28:25 -0700
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Subject: Re: [PATCH] bpf: fix check against plain integer v 'NULL'
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To:     Ben Dooks <ben.dooks@sifive.com>, linux-kernel@vger.kernel.org,
        bpf@vger.kernel.org
Cc:     Sudip Mukherjee <sudip.mukherjee@sifive.com>,
        Jude Onyenegecha <jude.onyenegecha@sifive.com>
References: <20220714100322.260467-1-ben.dooks@sifive.com>
From:   Yonghong Song <yhs@fb.com>
In-Reply-To: <20220714100322.260467-1-ben.dooks@sifive.com>
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On 7/14/22 3:03 AM, Ben Dooks wrote:
> When checking with sparse, btf_show_type_value() is causing a
> warning about checking integer vs NULL when the macro is passed
> a pointer, due to the 'value != 0' check. Stop sparse complaining
> about any type-casting by adding a cast to the typeof(value).
> 
> This fixes the following sparse warnings:
> 
> kernel/bpf/btf.c:2579:17: warning: Using plain integer as NULL pointer
> kernel/bpf/btf.c:2581:17: warning: Using plain integer as NULL pointer
> kernel/bpf/btf.c:3407:17: warning: Using plain integer as NULL pointer
> kernel/bpf/btf.c:3758:9: warning: Using plain integer as NULL pointer
> 
> Signed-off-by: Ben Dooks <ben.dooks@sifive.com>

Acked-by: Yonghong Song <yhs@fb.com>