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Date: Tue, 10 Jul 2007 11:33:49 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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Subject: Re: [x86 setup 17/33] A20 handling code
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Sender: linux-arch-owner@vger.kernel.org
To: Jan Engelhardt <jengelh@computergmbh.de>
Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, andi@firstfloor.org, akpm@linux-foundation.org
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Jan Engelhardt wrote:
> On Jul 9 2007 19:51, H. Peter Anvin wrote:
> 
>> +		status = inb(0x64);
>> +		if (status & 1) {
>> +			/* Read and discard input data */
>> +			io_delay();
>> +			(void)inb(0x60);
> 
> Is the (void) cast needed for some obscure reason? Let's hope inb _is_ declared
> as volatile. (Minus the volatile flames.
> 

The (void) cast is there as a stylistic device, it tells the human
reader "yes, I really meant to read this value and throw it away."

	-hpa