[libcxx] [llvm] [libc++] Kickstart C++29 support (PR #215820)

[Hristo Hristov via llvm-commits]

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@@ -1533,6 +1533,14 @@ def add_version_header(tc):
             },
             "headers": ["variant"],
         },
+        {
+            "name": "__cpp_lib_view_interface",
+            "values": {
+                "c++29": 202606,
----------------
Zingam wrote:

> Basically LGTM.
> 
> Possibly improvement:
> 
> Also, it might be more consistent to remove this entry or add all new C++29 FTMs.

I think adding all new C++29 FTMs are better handled as a separate follow-up task.

https://github.com/llvm/llvm-project/pull/215820