It is. This is discussed in the
LinuxCon 2012:
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This is again referenced in the
ARM community:
It's quite interesting that the speculation from 6 years ago becomes true. ARM developers knew that not all ARMv8 processors will run 32-bit code 6 years ago, and I do believe Microsoft knew that as well.
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If you don't believe the presentation made by ARM on events of Linux Foundation,
@jdb8167 pointed a source directly from arm document. Is this convincing enough to you now?
The OS can detect the absence of aarch32. If you run
lscpu
in a linux VM on M1 you will notice that there is no 32-bit in op-mode,:
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But 32-bit does appear on raspberry pi:
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