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Date: Tue, 19 Oct 2010 15:10:48 -0700
From: Randy Dunlap <randy.dunlap@oracle.com>
To: lkml <linux-kernel@vger.kernel.org>
Cc: Stefani Seibold <stefani@seibold.net>
Subject: kfifo must_check warning
Message-Id: <20101019151048.ae79bb25.randy.dunlap@oracle.com>
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In 2.6.36-rc8, I see this build warning:

drivers/char/n_gsm.c: In function 'gsm_dlci_alloc':
drivers/char/n_gsm.c:1580: warning: ignoring return value of '__kfifo_must_check_helper', declared with attribute warn_unused_result

The helper seems to be getting in the way (?).  The driver code does this:

	if (kfifo_alloc(&dlci->_fifo, 4096, GFP_KERNEL) < 0) {
		kfree(dlci);
		return NULL;
	}

Should the driver code be doing something else?
or should the kfifo_alloc() macro be checking the result of the helper?


thanks,
---
~Randy
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