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From: Lukas Bulwahn <lukas.bulwahn@gmail.com>
To: "Liam R . Howlett" <Liam.Howlett@oracle.com>,
	Matthew Wilcox <willy@infradead.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	linux-mm@kvack.org
Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org,
	Lukas Bulwahn <lukas.bulwahn@gmail.com>
Subject: [PATCH 1/1] lib: maple_tree: remove unneeded initialization in mtree_range_walk()
Date: Wed, 26 Oct 2022 14:00:29 +0200	[thread overview]
Message-ID: <20221026120029.12555-2-lukas.bulwahn@gmail.com> (raw)
In-Reply-To: <20221026120029.12555-1-lukas.bulwahn@gmail.com>

Before the do-while loop in mtree_range_walk(), the variables next, min,
max need to be initialized. The variables last, prev_min and prev_max are
set within the loop body before they are eventually used after exiting the
loop body.

As it is a do-while loop, the loop body is executed at least once, so the
variables last, prev_min and prev_max do not need to be initialized before
the loop body.

Remove unneeded initialization of last and prev_min.

The needless initialization was reported by clang-analyzer as Dead Stores.

As the compiler already identifies these assignments as unneeded, it
optimizes the assignments away. Hence:

No functional change. No change in object code.

Signed-off-by: Lukas Bulwahn <lukas.bulwahn@gmail.com>
---
 lib/maple_tree.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/maple_tree.c b/lib/maple_tree.c
index e1743803c851..fbde494444b8 100644
--- a/lib/maple_tree.c
+++ b/lib/maple_tree.c
@@ -2903,8 +2903,8 @@ static inline void *mtree_range_walk(struct ma_state *mas)
 	unsigned long max, min;
 	unsigned long prev_max, prev_min;
 
-	last = next = mas->node;
-	prev_min = min = mas->min;
+	next = mas->node;
+	min = mas->min;
 	max = mas->max;
 	do {
 		offset = 0;
-- 
2.17.1



  reply	other threads:[~2022-10-26 12:01 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-10-26 12:00 [PATCH 0/1] Dead stores in maple-tree Lukas Bulwahn
2022-10-26 12:00 ` Lukas Bulwahn [this message]
2022-10-26 14:25   ` [PATCH 1/1] lib: maple_tree: remove unneeded initialization in mtree_range_walk() Liam Howlett
2022-10-26 14:23 ` [PATCH 0/1] Dead stores in maple-tree Liam Howlett
2022-10-27  7:43   ` Dan Carpenter
2022-10-27 17:16     ` Liam Howlett

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