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Subject: Re: make defconfig (Re: +
 x86-defconfigs-explicitly-unset-config_64bit-in-i386_defconfig.patch added to
 -mm tree)
To:     Alexey Dobriyan <adobriyan@gmail.com>, linux-kernel@vger.kernel.org
Cc:     daniel.diaz@linaro.org, sedat.dilek@gmail.com
References: <20200820212940.Kq1ky-JHH%akpm@linux-foundation.org>
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From:   Randy Dunlap <rdunlap@infradead.org>
Message-ID: <dc2fbc95-8c8a-5613-f4bd-f29328bb695c@infradead.org>
Date:   Fri, 21 Aug 2020 10:27:19 -0700
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On 8/21/20 10:22 AM, Alexey Dobriyan wrote:
> On Thu, Aug 20, 2020 at 02:29:40PM -0700, akpm@linux-foundation.org wrote:
>> Subject: x86/defconfigs: Explicitly unset CONFIG_64BIT in i386_defconfig
>>
>> A recent refresh of the defconfigs got rid of the following (unset)
>> config:
>>
>>   # CONFIG_64BIT is not set
>>
>> Innocuous as it seems, when the config file is saved again the
>> behavior is changed so that CONFIG_64BIT=y.
>>
>> Currently,
>>
>>   $ make i386_defconfig
>>   $ grep CONFIG_64BIT .config
>>   CONFIG_64BIT=y
>>
>> whereas previously (and with this patch):
>>
>>   $ make i386_defconfig
>>   $ grep CONFIG_64BIT .config
>>   # CONFIG_64BIT is not set
> 
> It is highly, highly, highly advisable to always pass ARCH when dealing
> with 32/64-bit archs:
> 
> 	+---------------------------------------+
> 	|	make ARCH=x86_64 defconfig	|
> 	|	make ARCH=i386 defconfig	|
> 	+---------------------------------------+

I certainly always do that and I also avoid
ARCH=x86
although it is supported/allowed.

-- 
~Randy