aaron.ballman planned changes to this revision.
aaron.ballman added a comment.

In D131012#3695110 <https://reviews.llvm.org/D131012#3695110>, @anakryiko wrote:

> This will severly break BPF users, as we have a heavy reliance on `const 
> volatile` variables being allocated to `.rodata`, which are passed to BPF 
> verifier in Linux kernel as read-only values. This is critical for BPF 
> Complie Once - Run Everywhere approach of writing portable BPF applications. 
> We've been relying on this behavior for years now and changes this will break 
> many existing BPF applications.

Thank you for this feedback! I guess I'm a bit surprised given the contents 
from the issue seem to imply that BPF needed Clang's behavior to change: `Note 
that this is causing practical difficulties: the kernel's bpftool is generating 
different skeleton headers for BPF code compiled from LLVM and GCC, because the 
names of the containing sections get reflected.`

That said, I'm asking on the WG14 reflectors whether there's a normative 
requirement here or not, so I'm marking this as having planned changes until I 
hear back from WG14 and until we've resolved whether the changes will fix code 
vs break code (or both!) so we don't accidentally land this.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D131012/new/

https://reviews.llvm.org/D131012

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