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Date:   Wed, 4 Oct 2023 16:02:01 +0100 (BST)
From:   "Maciej W. Rozycki" <macro@orcam.me.uk>
To:     Su Hui <suhui@nfschina.com>
cc:     Dan Carpenter <dan.carpenter@linaro.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        rafael@kernel.org, linux-kernel@vger.kernel.org,
        kernel-janitors@vger.kernel.org
Subject: Re: [PATCH] driver base: slience unused warning
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Message-ID: <alpine.DEB.2.21.2310041557310.61599@angie.orcam.me.uk>
References: <45027fa0-cda5-2a80-f1cd-ed805d2717ee@nfschina.com>
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On Fri, 8 Sep 2023, Su Hui wrote:

> This variable is been used but never be read, so gcc and W=1 give such
> warning.
> 
> drivers/base/module.c:36:6: error:
> variable ‘no_warn’ set but not used [-Werror=unused-but-set-variable]
> 
> I wanted to use "__maybe_unused" to avoid  this warning.
> 
> However it seems like a wrong using of "__maybe_unused" as Greg KH said:
> 
> "But no_warn is being used in this file, it's being set but not read
> which is ok.  That's a real use, so this change really isn't correct,
> sorry."

 The warning itself is a real issue to be sorted though.  Is this a use 
case for `#pragma GCC diagnostic'?

  Maciej