Re: [PATCH for-9.0] meson.build: Disable -fzero-call-used-regs on OpenBSD

[Brad Smith]

On 4/11/2024 8:12 AM, Thomas Huth wrote:
> On 11/04/2024 14.08, Thomas Huth wrote:
> > QEMU currently does not work on OpenBSD since the -fzero-call-used-regs
>
> That should be "OpenBSD 7.5" ... older versions are fine since they 
> are using an older version of Clang that does not have 
> -fzero-call-used-regs yet, I think.

About the compiler version that is correct. Between 7.4 and 7.5 we 
upgraded from Clang 13 to 16.

-fzero-call-used-regs  was added with the 15 release.

https://github.com/llvm/llvm-project/commit/deaf22bc0e306bc44c70d2503e9364b5ed312c49

Retguard is also used to mitigate ROP exploits and is enabled by default.

https://www.openbsd.org/papers/asiabsdcon2019-rop-paper.pdf