Re: [RFC/RFT,V2] CFI: Add support for gcc CFI in aarch64

Sami Tolvanen
2023-03-27T22:18:28Z

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