2021-05-07 13:17:03

by Jiapeng Chong

Subject: [PATCH] sysctl: Remove redundant assignment to first

Variable first is set to '0', but this value is never read as it is
not used later on, hence it is a redundant assignment and can be
removed.

Clean up the following clang-analyzer warning:

kernel/sysctl.c:1562:4: warning: Value stored to 'first' is never read
[clang-analyzer-deadcode.DeadStores].

Reported-by: Abaci Robot <[email protected]>
Signed-off-by: Jiapeng Chong <[email protected]>
---
kernel/sysctl.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 14edf84..58beeba 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -1559,7 +1559,6 @@ int proc_do_large_bitmap(struct ctl_table *table, int write,
}

bitmap_set(tmp_bitmap, val_a, val_b - val_a + 1);
- first = 0;
proc_skip_char(&p, &left, '\n');
}
left += skipped;
--
1.8.3.1

2021-05-07 15:07:26

by Matthew Wilcox

Subject: Re: [PATCH] sysctl: Remove redundant assignment to first

On Fri, May 07, 2021 at 06:15:54PM +0800, Jiapeng Chong wrote:
> Variable first is set to '0', but this value is never read as it is
> not used later on, hence it is a redundant assignment and can be
> removed.
>
> Clean up the following clang-analyzer warning:
>
> kernel/sysctl.c:1562:4: warning: Value stored to 'first' is never read
> [clang-analyzer-deadcode.DeadStores].

While this is true, it is incomplete. The 'first' declaration should be
moved into the 'else' arm of the 'if (write)' conditional.