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Date: Fri, 3 May 2024 14:29:12 +0100
From: Matthew Wilcox <willy@infradead.org>
To: Kuan-Wei Chiu <visitorckw@gmail.com>
Cc: akpm@linux-foundation.org, Liam.Howlett@oracle.com, nathan@kernel.org,
	ndesaulniers@google.com, morbo@google.com, justinstitt@google.com,
	linux-kernel@vger.kernel.org, maple-tree@lists.infradead.org,
	linux-mm@kvack.org, llvm@lists.linux.dev, jserv@ccns.ncku.edu.tw
Subject: Re: [PATCH] maple_tree: Fix build failure with W=1 and LLVM=1
Message-ID: <ZjTmqM4ePSZgSt9_@casper.infradead.org>
References: <20240503095027.747838-1-visitorckw@gmail.com>
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On Fri, May 03, 2024 at 09:01:06PM +0800, Kuan-Wei Chiu wrote:
> On Fri, May 03, 2024 at 01:20:32PM +0100, Matthew Wilcox wrote:
> > On Fri, May 03, 2024 at 05:50:27PM +0800, Kuan-Wei Chiu wrote:
> > > When compiling library code using "make W=1 LLVM=1 lib/", clang
> > > generated the following compilation errors:
> > > 
> > > lib/maple_tree.c:351:21: error: unused function 'mte_set_full' [-Werror,-Wunused-function]
> > > static inline void *mte_set_full(const struct maple_enode *node)
> > 
> > Uh, clang is wrong to flag these as an error.  They're just not used
> > yet.
> 
> I think it's because the kernel defaults to treating all compilation
> warnings as errors. If you turn off the option to treat compilation
> warnings as errors, they will be treated as warnings instead. Should I
> update my commit message to change compilation errors to compilation
> warnings?

just don't use W=1 and clang.