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Subject: Re: [PATCH V3 XRT Alveo 03/18] fpga: xrt: xclbin file helper
 functions
To:     Lizhi Hou <lizhi.hou@xilinx.com>, linux-kernel@vger.kernel.org
Cc:     linux-fpga@vger.kernel.org, maxz@xilinx.com,
        sonal.santan@xilinx.com, michal.simek@xilinx.com,
        stefanos@xilinx.com, devicetree@vger.kernel.org, mdf@kernel.org,
        robh@kernel.org, Max Zhen <max.zhen@xilinx.com>
References: <20210218064019.29189-1-lizhih@xilinx.com>
 <20210218064019.29189-4-lizhih@xilinx.com>
 <4628ef05-27d1-b92f-9126-27a1f810c608@redhat.com>
 <3b73400c-cca1-60af-4eea-ed85de77a977@xilinx.com>
From:   Tom Rix <trix@redhat.com>
Message-ID: <c79176af-8d0c-2300-3e4a-dfa604f10a62@redhat.com>
Date:   Sun, 28 Feb 2021 08:54:29 -0800
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On 2/26/21 1:23 PM, Lizhi Hou wrote:
> Hi Tom,
>
>
snip

>>
>> I also do not see a pragma pack, usually this is set of 1 so the compiler does not shuffle elements, increase size etc.
> This data structure is shared with other tools. And the structure is well defined with reasonable alignment. It is compatible with all compilers we have tested. So pragma pack is not necessary.

You can not have possibly tested all the configurations since the kernel supports many arches and compilers.

If the tested existing alignment is ok, pragma pack should be a noop on your tested configurations.

And help cover the untested configurations.

Tom