[libc-commits] [libc] [libc][docs] add `builtin_compatibility` (PR #200539)

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hulxv wrote:

> I'm sorry, I thought I'd written a review for this. Can you please tell me a bit more about this? My biggest worry is that this is a big table that won't get maintained, and I don't know off hand if anyone will reference it. The table itself is structured correctly, etc., but I worry that it will be rapidly out of date and ignored.
> 
> (this isn't a no! I just want to know more about what we're taking on)

@lntue suggested adding this document due to issues we are facing when using __builtins_* with different gcc versions to be aware of what is not supported

like this: https://github.com/llvm/llvm-project/actions/runs/26666406362/job/78600602520#step:5:71

https://github.com/llvm/llvm-project/pull/200539