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Date:   Mon, 9 May 2022 14:59:47 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Tom Rix <trix@redhat.com>
Cc:     hughd@google.com, akpm@linux-foundation.org, nathan@kernel.org,
        ndesaulniers@google.com, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, llvm@lists.linux.dev
Subject: Re: [PATCH] mm/shmem: initialize folio to NULL
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On Mon, May 09, 2022 at 08:31:16AM -0400, Tom Rix wrote:
> The clang build fails with
> mm/shmem.c:1704:7: error: variable 'folio' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
>   if (!page) {
>        ^~~~~
> The error handler for !page jumps to an if-check for an unset folio.
> So initialize folio to NULL.

I appreciate you're trying to help, but the fourth report of a problem
adds more noise than utility.

https://lore.kernel.org/linux-mm/?q=shmem+folio

shows emails about this from the cgelbot, Dan Carpenter, SeongJae Park,
Colin King, Nathan Chancellor and Sebastian Siewior.  So actually you
were seventh, not fourth.