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From: DJ Delorie <dj@redhat.com>
To: Jeff Law <jeffreyalaw@gmail.com>
Cc: libc-alpha@sourceware.org
Subject: Re: [patch/idea] Add register scrambling to testsuite
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Date: Mon, 13 Jun 2022 12:43:13 -0400
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Jeff Law via Libc-alpha <libc-alpha@sourceware.org> writes:
> If you wanted to get nasty you could intercept all calls going through 
> the PLT and do something similar there as well.

The LD_AUDIT interface may or may not be able to do that, if the backend
doesn't preserve all registers "for our convenience" :-)

Would it be too much to ask for a "gcc -fscramble-regs" that writes
something to every call-clobbered reg in every prologue?  It wouldn't
have to be random, it would just have to be something that's obviously
wrong for most uses.