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Message-ID: <22d794613f70b04544e39e8861737af09365ae8a.camel@xry111.site>
Subject: Re: [PATCH 7/9] LoongArch: Tweak CFLAGS for Clang compatibility
From:   Xi Ruoyao <xry111@xry111.site>
To:     WANG Xuerui <kernel@xen0n.name>,
        Huacai Chen <chenhuacai@kernel.org>
Cc:     WANG Rui <wangrui@loongson.cn>, loongarch@lists.linux.dev,
        linux-kbuild@vger.kernel.org, llvm@lists.linux.dev,
        linux-kernel@vger.kernel.org, WANG Xuerui <git@xen0n.name>
Date:   Sat, 24 Jun 2023 01:00:37 +0800
In-Reply-To: <20230623134351.1898379-8-kernel@xen0n.name>
References: <20230623134351.1898379-1-kernel@xen0n.name>
         <20230623134351.1898379-8-kernel@xen0n.name>
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On Fri, 2023-06-23 at 21:43 +0800, WANG Xuerui wrote:

> -cflags-y=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=
=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=
+=3D -G0 -pipe -msoft-float

-msoft-float should not be removed.  Our consensus (made when I was
developing https://gcc.gnu.org/r13-6500) is -mabi=3Dlp64s does *not*
disable floating point instructions, but only disable FPRs for passing
arguments and return values.  So w/o -msoft-float (or -mfpu=3Dnone) GCC is
allowed to generate FP instructions everywhere in kernel and it may
cause kernel FPD exception in the future.

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