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Date: Tue, 22 Jan 2013 11:07:04 +0100
From: =?ISO-8859-1?Q?Vincent_Stehl=E9?= <v-stehle@ti.com>
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To: Mark Brown <broonie@opensource.wolfsonmicro.com>
CC: <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] regmap: debugfs: Fix compilation warning
References: <1358779015-25735-1-git-send-email-v-stehle@ti.com> <20130122064121.GC1766@opensource.wolfsonmicro.com>
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On 01/22/2013 07:41 AM, Mark Brown wrote:
(..)
> This sort of fix is not a good idea, you're just shutting the
> warning up without any sort of analysis explaining why it's
> generated in error.  If it's generating a spurious error that's a
> compiler bug.

In the regmap_debugfs_get_dump_start() function control flow, I think
the compiler cannot know for sure that the list_for_each_entry()
iterates at least once.:

	regmap_debugfs_get_dump_start()
	{
		unsigned int ret;
		<snip some code, which does not touch ret>

		list_for_each_entry() {
			<snip some code>
			ret = <value>;
		}

		return ret;
	}

Do you think there is a way to "mark" the list_for_each_entry() as
iterating at least once? an __attribute__ maybe?

Best regards,

V.