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Date: Mon, 17 Feb 2014 14:46:45 -0800
From: Kent Overstreet <kmo@daterainc.com>
To: Randy Dunlap <rdunlap@infradead.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-bcache@vger.kernel.org
Subject: Re: New bcache compiler warning (was: Re: bcache: Minor fixes from
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On Mon, Feb 17, 2014 at 02:44:47PM -0800, Randy Dunlap wrote:
> Could that cause a truncation?  unsigned means unsigned int.
> Can unsigned int be smaller (fewer bits) than the k pointer?
> If so, is that OK or a problem?

It's just truncating the offset of the pointer within the struct bset, which is
part of a btree node - the thing that's being cast is restricted to be no bigger
than a btree node, which is at most a few mb.