From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [PATCH] bitops: simplify generic bit finding functions
Date: Sun, 27 Apr 2008 21:36:38 +0100
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To: Harvey Harrison <harvey.harrison@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>, Ingo Molnar <mingo@elte.hu>, Andrew Morton <akpm@linux-foundation.org>, LKML <linux-kernel@vger.kernel.org>, linux-sparse@vger.kernel.org

On Sun, Apr 27, 2008 at 01:29:21PM -0700, Harvey Harrison wrote:

> Oh, I didn't realize, I only did this because sparse started spewing out
> lots of:
> include/linux/bitops.h:166:32: warning: shift too big (65536) for type unsigned long
> 
> due to shift by size there, and again on line 202...I just wanted something
> that sparse wouldn't warn about and was a little easier to understand to boot.

That's a sparse problem, really.  I wonder if we simply should introduce a
new node type: EXPR_WARN.  So that expand would generate those from things
like division by zero/overflow/bad shift *and* emitting an insn for those
would generate a stored warning.

Objections?