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Date: Mon, 6 May 2024 10:29:09 -0400
From: "Liam R. Howlett" <Liam.Howlett@oracle.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Nathan Chancellor <nathan@kernel.org>,
        Matthew Wilcox <willy@infradead.org>,
        Kuan-Wei Chiu <visitorckw@gmail.com>, ndesaulniers@google.com,
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        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
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* Andrew Morton <akpm@linux-foundation.org> [240504 19:03]:
> On Fri, 3 May 2024 09:08:21 -0700 Nathan Chancellor <nathan@kernel.org> wrote:
> 
> > This patch has effectively been sent four times now:
> > 
> > https://lore.kernel.org/all/20220914101829.82000-1-jiapeng.chong@linux.alibaba.com/
> > https://lore.kernel.org/all/20230217084647.50471-1-jiapeng.chong@linux.alibaba.com/
> > https://lore.kernel.org/all/20230319132903.1702426-1-trix@redhat.com/
> > https://lore.kernel.org/all/20240503095027.747838-1-visitorckw@gmail.com/ (this change obviously)
> > 
> > Your first comment from the 2022 patch:
> > 
> >   They're not used now, but they will be in a release or two.
> > 
> > I think a few releases have passed since then :) I don't personally care
> > if there is a solution here or not, as I don't test with W=1 (there's
> > enough to do at W=0 :P), but maybe it is time for either __maybe_unused
> > (as that strikes at the heart of the issue) or at the very least a
> > comment saying "hey, these functions are currently unused but there are
> > plans for them to be used, so don't remove them", rather than just
> > saying the status quo?
> 
> We could just slap a #if 0 around them.  But I don't think it'll kill us to
> have to type them in again one day ;)

I've had people try to use this bit for other reasons, even with these
functions.

If we're dropping this code, then we should put something in to avoid it
disappearing on us.

I am working on the use of these functions in a branch, but I don't have
a timeline of when that feature will land.

Thanks,
Liam