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From: Paul Rubin <no.email@nospam.invalid>
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Subject: Re: is there a version of unix written in Ada
Date: Wed, 30 Sep 2020 13:33:32 -0700
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"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:
> I want an OS protecting from compilers I do not trust without
> performance loss. 

That is not possible.  Traditional OS's use memory protection hardware
for that, but that hardware introduces performance loss.  Singularity
aimed to avoid the loss by relying on trusted compilers.  It's not
anything like MSDOS, since MSDOS never tried to coordinate multiple
processors and intercommunicating processes.