[clang] [clang-tools-extra] [libcxx] [llvm] [libc++][ranges] P2542R8: Implement `views::concat` (PR #120920)

[Hristo Hristov via llvm-commits]

Zingam wrote:

> > > @frederick-vs-ja just follow up on this, is there anything else I need to address for this PR?
> > 
> > 
> > It looks like you are missing the Release Notes entry, FTM is not set, etc. house keeping stuff. Please check some other complete PRs for what else you need to do.
> 
> What's FTM? Can you give me an example PR that has those?

https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2024/p2542r8.html#feature-test-macro

This is a completed PR of mine https://github.com/llvm/llvm-project/pull/106870 but it isn't new and requirements might have changed since.
You need to modify libcxx/utils/generate_feature_test_macro_components.py and run it (add the FTM yourself if it is missing) to generate, whatever it is  necessary.

https://github.com/llvm/llvm-project/pull/120920