Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Message-ID: <ad45e0e0409b07ecb719743e4febb2853143986d.camel@xry111.site>
Subject: Re: build failure of next-20221005 due to 4078ec1ef5ed ("LoongArch:
 Use TLB for ioremap()")
From:   Xi Ruoyao <xry111@xry111.site>
To:     Huacai Chen <chenhuacai@loongson.cn>
Cc:     WANG Xuerui <kernel@xen0n.name>, loongarch@lists.linux.dev,
        linux-kernel@vger.kernel.org, linux-next@vger.kernel.org,
        Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Date:   Wed, 05 Oct 2022 22:06:56 +0800
In-Reply-To: <CADVatmOmtd0jfzNvpyMiQnN0nUn3qZFjLnTjxrn7km3p-grwpQ@mail.gmail.com>
References: <Yz1t6rPLOzKT8Id+@debian>
         <CAAhV-H7FoDEEtqF_ZOwTGPeGK-4wpzsxEqvO+iuq=KpEuDUofQ@mail.gmail.com>
         <CADVatmOmtd0jfzNvpyMiQnN0nUn3qZFjLnTjxrn7km3p-grwpQ@mail.gmail.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
User-Agent: Evolution 3.46.0 
MIME-Version: 1.0
Precedence: bulk

Hi Huacai,

Try:

#define iounmap(addr) ((void)(addr))

This is how we normally silence an unused variable or parameter warning.
Not sure if the kernel uses the same convention though.

On Wed, 2022-10-05 at 13:54 +0100, Sudip Mukherjee wrote:
> On Wed, Oct 5, 2022 at 1:30 PM Huacai Chen <chenhuacai@kernel.org>
> wrote:
> >=20
> > Hi, Sudip,
> >=20
> > This seems a false positive. When the implementation of iounmap() is
> > empty (but this is completely legal I think), these drivers will
> > cause
> > "unused variable error".
>=20
> And that error will fail the build as allmodconfig will have
> CONFIG_WERROR=3Dy.
>=20

--=20
Xi Ruoyao <xry111@xry111.site>
School of Aerospace Science and Technology, Xidian University