john-brawn-arm wrote:

> This seems to add a new feature, is it really relevant for a backport?

This is the last piece of work to enable GCS in the LLVM toolchain (clang and 
lld support went in a while ago), and I was hoping to get everything in to LLVM 
19. It would be rather annoying to have this last part slip to LLVM 20.

The way GCS works is that the `-mbranch-protection=standard` command-line 
option marks generated objects with the GCS property, and lld then sets the GCS 
property on the output if all inputs have it, which then indicates to the 
operating system to enable GCS on that process. Without GCS support in 
libunwind that means it won't have the GCS property so anything that links with 
libunwind will have GCS disabled.

Though having said all this, I marked this for LLVM 19 as my reading of 
https://discourse.llvm.org/t/update-on-llvm-19-x-releases/80511 was that new 
features are still ok before RC2, but re-reading it it's a bit ambiguous: it 
says "New features will have to wait until LLVM 20 at this point" and my 
reading of that was that "this point" means RC2, so new features before RC2 is 
fine, but if "this point" meant "right now" that means new features aren't OK. 
If that's the case the it's reasonable for this to not go in RC2.

https://github.com/llvm/llvm-project/pull/99335
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits

Reply via email to