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From: Dongjiu Geng <gengdongjiu1@gmail.com>
Date: Thu, 3 Mar 2022 21:41:45 +0800
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Subject: what is the difference with and without crc extension support
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Hi,
     My program does not use CRC instructions=EF=BC=8Cbut I find the compil=
ed
binary has much difference between using "-march=3Darmv8-a+crc" and
using "-march=3Darmv8-a". Even stranger, when I use
"-march=3Darmv8-a+crc", I find my compiled binary can not run. but when
I change -O2 to -O0 based on "-march=3Darmv8-a+crc",  it can run. I  do
not  know what is the reason.. can you answer it? Thanks.