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Date:   Wed, 5 Apr 2023 04:49:24 -0700
From:   Dan Li <ashimida.1990@gmail.com>
To:     Sami Tolvanen <samitolvanen@google.com>
Cc:     Peter Zijlstra <peterz@infradead.org>,
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Subject: Re: [RFC/RFT,V2] CFI: Add support for gcc CFI in aarch64
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On 03/27, Sami Tolvanen wrote:
> On Mon, Mar 27, 2023 at 2:30 AM Peter Zijlstra <peterz@infradead.org> wrote:
> >
> > On Sat, Mar 25, 2023 at 01:54:16AM -0700, Dan Li wrote:
> >
> > > In the compiler part[4], most of the content is the same as Sami's
> > > implementation[3], except for some minor differences, mainly including:
> > >
> > > 1. The function typeid is calculated differently and it is difficult
> > > to be consistent.
> >
> > This means there is an effective ABI break between the compilers, which
> > is sad :-( Is there really nothing to be done about this?
> 
> I agree, this would be unfortunate, and would also be a compatibility
> issue with rustc where there's ongoing work to support
> clang-compatible CFI type hashes:
> 
> https://github.com/rust-lang/rust/pull/105452
> 
> Sami

Hi Sami,

Thanks for the info, I need to learn about it :)
Is there anything else that needs to be improved?

Thanks,
Dan