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Date: Mon, 22 Jan 2024 09:58:16 -0500
From: "Liam R. Howlett" <Liam.Howlett@Oracle.com>
To: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>, maple-tree@lists.infradead.org,
        linux-mm@kvack.org, kernel-janitors@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] maple_tree: avoid duplicate variable init in
 mast_spanning_rebalance()
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References: <20240122102000.29558-1-lukas.bulwahn@gmail.com>
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* Lukas Bulwahn <lukas.bulwahn@gmail.com> [240122 05:22]:
> The local variables r_tmp and l_tmp in mast_spanning_rebalance() are
> already initialized at its declaration; there is no need to assign the
> value again.
> 
> Remove the duplicate initialization of {r,l}_tmp. No functional change.
> Due to common compiler optimizations, also no change to object code.

Hello!

Thanks for this patch and well stated change log.

> 
> This issue was identified with clang-analyzer's dead stores analysis.
> 
> Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>

Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>

> ---
>  lib/maple_tree.c | 2 --
>  1 file changed, 2 deletions(-)
> 
> diff --git a/lib/maple_tree.c b/lib/maple_tree.c
> index 7b161802860b..82fb5195c235 100644
> --- a/lib/maple_tree.c
> +++ b/lib/maple_tree.c
> @@ -2271,8 +2271,6 @@ bool mast_spanning_rebalance(struct maple_subtree_state *mast)
>  	struct ma_state l_tmp = *mast->orig_l;
>  	unsigned char depth = 0;
>  
> -	r_tmp = *mast->orig_r;
> -	l_tmp = *mast->orig_l;
>  	do {
>  		mas_ascend(mast->orig_r);
>  		mas_ascend(mast->orig_l);
> -- 
> 2.17.1
>