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Date: Tue, 10 Jul 2007 11:33:49 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Jan Engelhardt <jengelh@computergmbh.de>
CC: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org,
       andi@firstfloor.org, akpm@linux-foundation.org
Subject: Re: [x86 setup 17/33] A20 handling code
References: <11840359321823-git-send-email-hpa@zytor.com> <11840360383913-git-send-email-hpa@zytor.com> <11840361432207-git-send-email-hpa@zytor.com> <11840362483663-git-send-email-hpa@zytor.com> <11840363531039-git-send-email-hpa@zytor.com> <11840364593068-git-send-email-hpa@zytor.com> <1184036564610-git-send-email-hpa@zytor.com> <11840366692770-git-send-email-hpa@zytor.com> <11840367741994-git-send-email-hpa@zytor.com> <11840368791603-git-send-email-hpa@zytor.com> <11840369841576-git-send-email-hpa@zytor.com> <11840370903975-git-send-email-hpa@zytor.com> <11840371953778-git-send-email-hpa@zytor.com> <11840373002601-git-send-email-hpa@zytor.com> <11840374052662-git-send-email-hpa@zytor.com> <1184037510289-git-send-email-hpa@zytor.com> <11840376162370-git-send-email-hpa@zytor.com> <11840377211519-git-send-email-hpa@zytor.com> <Pine.LNX.4.64.0707102025390.11053@fbirervta.pbzchgretzou.qr>
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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